JP2007316301A - Developer for replenishment, developing method and method of producing developer for replenishment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer for replenishment for stably obtaining an image with high definition in use over a long period, to provide a developing method using the developer for replenishment, and to provide a method of producing the developer for replenishment. <P>SOLUTION: The developer for replenishment is used for a two component developing method where an electrostatic charge image is developed while replenishing a development machine with a developer for replenishment, and also, a carrier made surplus at least in the development machine is exhausted from the development machine. The developer for replenishment at least comprises: a toner; inorganic particulates; and a magnetic carrier. The inorganic particulates have number mean particle diameters (D1) of 50 to 300 nm, and the developer for replenishment is prepared by beforehand mixing the inorganic particulates and the magnetic carrier, and thereafter mixing the same with the toner. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a replenishing developer used in an electrophotographic system, an electrostatic recording system, and an electrostatic printing system, a developing method using the replenishing developer, and a method for producing the replenishing developer.

In recent years, with the development of IT (information technology), means for outputting further high-definition images such as lowercase letters, photographs or color originals in a wide range of fields from offices to homes has been demanded. At the same time, there is a demand for performance (high durability) that does not deteriorate the image quality even when a large number of copies or prints are made.
In an electrophotographic image forming method, a highly durable electrophotographic process has been proposed in which a photoconductor with improved surface resistance and abrasion resistance and scratch resistance is mounted on a photoconductor carrying an electrostatic latent image. Yes.
However, since the photoconductor with improved wear resistance and scratch resistance has a small amount of abrasion on the surface of the photoconductor, the charged product adhering to the surface of the photoconductor generated in the charging step is hardly scraped off. As a result, when used in a high humidity environment, the charged product may adhere to the surface of the photoreceptor, and the remaining charged product may reduce the surface resistance of the photoreceptor and cause image flow.

In response to such a problem, inorganic fine particles having a polishing action on the surface of the photosensitive member are externally added to the toner particles, and the inorganic fine particles present on the toner surface are supplied to a portion where the surface of the photosensitive member is polished. There is known a method for stripping off a charged product adhering to the surface and improving image defects such as image flow. (For example, see Patent Document 1)
The portion to be polished is a cleaning portion in an image forming method in which a transfer residual toner is removed from the photoreceptor using a cleaning blade. The inorganic fine particles stay in the blocking layer formed in the cleaning nip portion between the cleaning blade and the photosensitive member, whereby the photosensitive member is polished. In addition, a polishing site in a so-called simultaneous development cleaning system that does not have a cleaning step and collects transfer residual toner to a developing device simultaneously with development is a charging auxiliary member, and inorganic fine particles attached to the charging auxiliary member are photosensitive members. To polish.

However, the inorganic fine particles having a polishing action used here have a large particle size and a broad particle size distribution, and in order to obtain an effect of uniformly polishing the surface of the photoreceptor, a large amount is externally added to the toner. There was a need. However, if a large amount of the above-mentioned inorganic fine particles having an abrasive action are externally added to the toner surface, the fluidity of the toner is lowered, and when the toner is supplied to the developing device, the toner is not sufficiently charged and fogging occurs. Or the toner may scatter and contaminate the member. Even in the two-component development system, the deterioration of the fluidity of the toner leads to the deterioration of the mixing property with the carrier, the charge amount of the developer becomes uneven, and the development characteristics may be deteriorated.
Further, it has been pointed out that the inorganic fine particles used here generally have a weak adhesive force with the toner and exist in a state free from the toner. The inorganic fine particles released in the developing device behave like a carrier in two-component development, and the charge amount of the toner may be extremely increased, and charge up may occur.
Accordingly, development of inorganic fine particles and a method for adding inorganic fine particles that do not affect toner physical properties and development characteristics is expected.

In addition, in order to stably maintain the polishing effect over a long period of time, it is necessary to stably supply inorganic fine particles having an abrasive action to a portion where the photoreceptor is polished over a long period of time. In general, the inorganic fine particles externally added to the toner particles are supplied from the toner to a portion where the photoreceptor is polished. However, depending on the inorganic fine particles to be used, the supply of the abrasive to the polishing site is insufficient, and the effect of removing the charged product may not be sufficiently obtained.

In order to solve such a problem, a method of polishing a photoconductor in the presence of an abrasive on the surface of carrier particles has been proposed (for example, see Patent Document 1). A carrier prepared by externally adding calcium carbonate as a polishing agent or a developer prepared by a carrier containing calcium carbonate in the carrier coat layer rubs the amorphous photoreceptor on the developing sleeve and polishes the photoreceptor surface layer. Therefore, it is intended to suppress the image flow. However, in contrast to the polishing of the surface of the photosensitive member by the abrasive held by the cleaning blade, the contact charger, or the contact charging auxiliary member that is always in contact with the photosensitive member, the polishing in the developing nip with the abrasive present on the carrier surface layer is not used. The polishing ability is not enough. Therefore, continuous use may reduce the polishing effect and cause image flow. Further, it is not possible to completely prevent the abrasive from being detached from the carrier surface or the carrier coat surface layer. Therefore, the abrasive may be lost from the carrier surface or the carrier coat surface layer due to long-term use, and the polishing effect may be reduced. In addition, although not supposed in the above proposal, even if the temporarily detached abrasive moves to a portion where the photoreceptor is polished, for example, a cleaning unit, and the surface of the photoreceptor can be temporarily polished, Since it is not replenished, only a certain amount of abrasive particles are present in the development process at the beginning of use. After that, since the carrier with externally added / internally added abrasive is not replenished in the developing unit, the abrasive in the development process system gradually becomes insufficient, and it is difficult to maintain the polishing effect for a long time. When it increases, image flow occurs.

  In addition, as a method for making the developer highly durable, a method has been proposed in which replenishment toner and carrier are replenished at a fixed ratio, and image formation is performed while gradually replacing the carrier in the developing device, whose development performance has deteriorated, with a new carrier. (For example, refer to Patent Document 3).

  Proposal that inorganic fine particles are present in the carrier in the replenishment developer replenished at a fixed ratio together with the replenishing toner (for example, Patent Document 4), and other proposals that the carrier and the inorganic fine particles are mixed in advance. (See, for example, Patent Document 5). However, according to these proposals, it is possible to obtain a certain effect for suppressing the fluctuation of the charging ability of the carrier due to continuous use, but in the process using the photoconductor with improved wear resistance and scratch resistance. , Image flow will occur. This is not a material selection or method based on the premise of polishing of the surface of the photoconductor and is not based on the concept of supplying inorganic fine particles to the polishing site, so that a sufficient polishing effect cannot be obtained and the photoconductor The surface has a low resistance, which leads to the occurrence of image flow.

As described above, inorganic fine particles are supplied from an optimal replenishment developer as a method for stably and efficiently supplying inorganic fine particles over a long period of time without affecting the toner physical properties and development characteristics. Development of a method to do this is expected.
JP 61-278861 A Japanese Patent Laid-Open No. 08-190227 Japanese Patent Publication No. 2-21591 JP 2004-287073 A JP 2005-091878 A

The present invention has been made in view of the above circumstances of the prior art.
That is, an object of the present invention is a replenishment developer containing at least a toner, inorganic fine particles, and a magnetic carrier, developing an electrostatic image while replenishing the replenishment developer to the developer, and at least a developer It is an object of the present invention to provide a replenishing developer for use in a two-component developing method for discharging an excessive carrier inside from a developing device. Another object of the present invention is to provide a developing method using the above-mentioned replenishment developer in order to obtain high durability and high image quality. Another object of the present invention is to provide a method for producing a replenishment developer that is optimal for achieving the above object.

As a result of intensive studies, the present inventors have found that it is possible to achieve both high durability stability and high image quality by using a replenishment developer containing toner, inorganic fine particles, and a carrier by a specific method. I found it.
That is, the compatibility between the high durability stability and the high image quality can be achieved by using the replenishment developer described in any one of (1) to (6) below.
(1) Replenishment development for use in a two-component development method in which an electrostatic image is developed while replenishing developer is replenished to the developing unit, and at least the excess carrier inside the developing unit is discharged from the developing unit. An agent,
The replenishment developer contains at least a toner, inorganic fine particles, and a magnetic carrier,
The inorganic fine particles have a number average particle diameter (D1) of 50 to 300 nm,
The replenishment developer is prepared by mixing the inorganic fine particles and the magnetic carrier in advance and then mixing with toner.
(2) The replenishment developer according to (1), wherein the inorganic fine particles contain one or more elements selected from magnesium, calcium, strontium, barium and cerium.
(3) The replenishment according to (1) or (2), wherein the inorganic fine particles are at least one selected from magnesium silicate, calcium titanate, strontium titanate, barium titanate and cerium oxide. Developer.
(4) The replenishment developer according to (1), wherein the inorganic fine particles contain silicon nitride.
(5) In any one of (1) to (4), the magnetic carrier is a mixture of the inorganic fine particles at a mass ratio of 0.01 to 10 parts by mass with respect to 100 parts by mass of the magnetic carrier. The developer for replenishment described.
(6) In any one of (1) to (5), the replenishment developer includes a toner in a mass ratio of 2 to 50 parts by mass with respect to 1 part by mass of the magnetic carrier. The developer for replenishment described.
(7) A two-component developing method for developing an electrostatic charge image while replenishing the replenishment developer to the developer, and discharging at least the excess carrier inside the developer from the developer. A developing method using the replenishing developer described in any one of (6).
(8) For replenishment for use in a two-component development method in which an electrostatic image is developed while replenishing the replenishment developer to the developer, and at least the excess carrier inside the developer is discharged from the developer. A method for producing a developer, comprising:
The inorganic fine particles have a number average particle diameter (D1) of 50 to 300 nm,
A method for producing a replenishing developer, wherein the inorganic fine particles and the magnetic carrier are mixed in advance and then mixed with toner.

  According to the present invention, an electrostatic image is developed while replenishing a developer with a replenishment developer containing at least toner, inorganic fine particles, and a magnetic carrier, and at least the excess carrier inside the developer is removed from the developer. Provided is a replenishment developer for use in a two-component development method to be discharged, and a method for producing the replenishment developer. The development method using the replenishment developer provides high image quality without image defects such as image flow. It is possible to output a stable image over a long period of time.

The present invention is described in detail below.
The present invention relates to a replenishment for use in a two-component development method in which an electrostatic image is developed while replenishing developer is replenished to a developing device, and at least the excess carrier inside the developing device is discharged from the developing device. A developer,
The replenishment developer contains at least a toner, inorganic fine particles, and a magnetic carrier,
The inorganic fine particles have a number average particle diameter (D1) of 50 to 300 nm,
The replenishment developer relates to a replenishment developer prepared by mixing the inorganic fine particles and the magnetic carrier in advance and then mixing with toner.

  Using a replenishment developer that satisfies this condition, the photoconductor having high photoconductor surface hardness with improved wear resistance, such as an amorphous silicon photoconductor (a-Si photoconductor), aluminum, In a high temperature and high humidity environment, when a conductive layer, an undercoat layer, a charge generation layer, a charge transport layer, and an organic photoreceptor having a protective layer on the outermost surface layer are combined on a conductive substrate such as SUS in order, There is no occurrence of image flow, and there is no difference in toner physical properties and development characteristics from the case where no inorganic fine particles are contained, and an excellent image can be obtained stably over a long period of time.

<Inorganic fine particles used in the replenishment developer of the present invention>
The inorganic fine particles used in the replenishment developer of the present invention may be those prepared so that the number average particle diameter (D1) is 50 to 300 nm. The number average particle diameter (D1) of the inorganic fine particles used in the present invention can be prepared, for example, by classification using a sieve.

When the number average particle diameter (D1) of the inorganic fine particles is less than 50 nm, the image density is lowered and the image flow is generated. Since the distribution of the inorganic fine particles is biased toward the fine particle size, the inorganic fine particles are physically strongly attached to the carrier, so that the inorganic fine particles are difficult to fly from the carrier surface toward the photoreceptor. In the system in which the transfer residual toner on the photosensitive member is cleaned with a blade, it is considered that as a result, sufficient inorganic fine particles are not supplied to the cleaning blade which is a polishing portion, the polishing effect becomes insufficient, and the image flow occurs. In addition, since the inorganic fine particles are not efficiently supplied to the cleaning blade that is the polishing site, it is believed that the inorganic fine particles that have flew fly through the cleaning blade and contaminate the charging member such as the charging roller, thereby reducing the image density. It is done.
Further, even in a system that does not have a cleaning process and collects transfer residual toner at the same time as development, as a result, sufficient inorganic fine particles are not supplied to the charging auxiliary member that is a polishing site, resulting in an insufficient polishing effect, and an image. Flow occurs.
On the other hand, when the number average particle diameter (D1) of the inorganic fine particles was larger than 300 nm, charge-up due to continuous use, fogging during replenishment, and image flow occurred. This is presumably because the inorganic fine particles released from the carrier increase and the free inorganic fine particles behaved like the carrier of the two-component developer, so that charge-up occurs. Further, it is considered that the fluidity of the developer is lowered, the mixing property with the replenishment developer is lowered, the charging becomes non-uniform, and fogging occurs.

The inorganic fine particles may treat the surface of the fine particles.
Examples of the surface treatment agent include a treatment agent such as a coupling agent, silicone oil, and fatty acid metal salt. By performing the surface treatment, for example, in the case of a coupling agent that is a compound having a hydrophilic group and a hydrophobic group, the hydrophilic group side covers the surface of the inorganic fine particles so that the hydrophobic group side becomes the outer side. The fluctuation of the triboelectric charge amount due to the environment can be suppressed, and the triboelectric charge amount can be easily controlled by a coupling agent into which a functional group such as amino group or fluorine is introduced.
Examples of coupling agents include titanate, aluminum, and silane coupling agents. Examples of fatty acid metal salts include zinc stearate, sodium stearate, calcium stearate, zinc laurate, aluminum stearate, and magnesium stearate. Similar effects can be obtained with stearic acid, which is a fatty acid.
The treatment method includes dissolving and dispersing the surface treatment agent to be treated in a solvent, adding inorganic fine particles therein, removing the solvent while stirring, a treatment method, a coupling agent, and a fatty acid metal salt. And a dry method in which the inorganic fine particles are directly mixed and treated with stirring.
In addition, it is not necessary to completely treat and coat the inorganic fine particles with respect to the surface treatment, and the inorganic fine particles may be exposed as long as the effect is obtained. That is, the surface treatment may be formed discontinuously.

  In addition, when the replenishment developer of the present invention prepared by mixing the inorganic fine particles and the magnetic carrier in advance and then mixing with the toner is used, the inorganic fine particles are used as a toner in a long-term use. It is possible to suppress fluctuations in the charging characteristics of the developer that occur when externally added, and a high-definition image can be stably obtained.

If there is no inorganic fine particles in the replenishment developer, even if the start developer contains inorganic fine particles, the inorganic fine particles are not replenished from the replenishment developer, so the polishing effect is temporary. Thus, the image flow is generated by long-term use.
In addition, a replenishing developer containing toner and inorganic fine particles added to the toner and a carrier has a remarkably low fluidity of the replenished toner, and continuously outputs images with a high image ratio. When a large amount of developer is continuously supplied, the toner may not be sufficiently charged due to poor mixing of the developer, and fogging may occur. In addition, since the inorganic fine particles themselves are difficult to separate from the toner, the supply amount of the inorganic fine particles to the polishing member is insufficient, and the effect of preventing the image flow may be weakened.

  The inorganic fine particles contained in the replenishment developer of the present invention are preferably inorganic fine particles containing one or more elements selected from magnesium, calcium, strontium, barium and cerium.

  When inorganic fine particles containing these elements are used, density fluctuations and image flow do not occur even during long-term use. It is presumed that the particles containing these elements are mixed more uniformly in the step of mixing with the carrier in advance due to the relationship between the specific gravity of the carrier and the inorganic fine particles. This is probably because the inorganic fine particles are not unevenly distributed in the replenishment developer, and the inorganic fine particles have been replenished stably.

  The inorganic fine particles contained in the replenishment developer of the present invention are preferably at least one kind of inorganic fine particles selected from at least magnesium silicate, calcium titanate, strontium titanate, barium titanate and cerium oxide.

  When these inorganic fine particles are used, image flow and filming on the photosensitive drum are suppressed, and in a system where blade cleaning is performed, a good image is stabilized without chipping of the blade or scratches on the surface of the photosensitive member. Can be obtained. It is considered that these inorganic fine particles have a hardness and a shape that do not cause scratches on the photoreceptor and can be appropriately polished to remove a charged product on the surface of the photoreceptor.

The inorganic fine particles contained in the replenishment developer of the present invention may contain silicon nitride.
This is because the shape is square, so that it is less likely to slip through the cleaning blade than the nearly spherical polyhedron, stays in the vicinity of the blade, increases the contact area with the photoconductor, and further, cubic and cuboid When the ridge line is in contact with the photosensitive member, it is possible to more effectively remove and scrape the adhered matter.

<About the magnetic carrier used in the replenishment developer of the present invention>
The magnetic carrier used in the developer for replenishment of the present invention is not particularly limited, and examples thereof include surface oxidized or unoxidized iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, and rare earth. Metal particles, alloy particles thereof, oxide particles, ferrite and the like can be used. Further, it may be a so-called resin-impregnated carrier in which a porous magnetic material (including porous ferrite) is impregnated with a resin, or a magnetic material-containing resin carrier in which a magnetic material is dispersed in the resin. .

Among the above magnetic carriers, it is preferable to use a magnetic substance-containing resin carrier in which a magnetic substance is dispersed in a resin.
As a method for producing the magnetic substance-containing resin carrier, there is a method obtained by polymerizing monomers constituting the resin in the presence of the magnetic substance.

  At this time, as monomers used for polymerization, in addition to vinyl monomers, bisphenols and epichlorohydrin for forming epoxy resins; phenols and aldehydes for forming phenol resins; urea resins are formed Urea and aldehydes for forming a melamine, and melamine and aldehydes for forming a melamine resin are used.

  As another method for producing the above magnetic substance-containing resin carrier, a vinyl-type or non-vinyl-type thermoplastic resin, a magnetic substance, and other additives are sufficiently mixed by a mixer, and then a heating roll, a kneader, and an extruder. There is a method in which a magnetic material-containing resin carrier core is obtained by melting and kneading using a kneader such as the above, and cooling and then pulverizing and classifying. At this time, it is preferable that the obtained magnetic body-containing resin carrier core is thermally or mechanically spheroidized and used as a magnetic body-containing resin carrier.

The amount of the magnetic substance used in the magnetic substance-containing resin carrier is 70 to 95% by mass (more preferably 80 to 92% by mass) with respect to the magnetic substance-containing resin carrier. It is preferable for reducing the size and ensuring sufficient mechanical strength. Furthermore, in order to adjust the magnetic characteristics of the magnetic carrier, a part of the magnetic substance contained in the magnetic substance-containing resin carrier may be replaced with a nonmagnetic inorganic compound.
In addition, the nonmagnetic inorganic compound has a specific resistance value larger than that of the magnetic substance, and the number average particle diameter of the nonmagnetic inorganic compound is larger than the number average particle diameter of the magnetic substance to increase the specific resistance value of the magnetic carrier. Is preferable.

  The magnetic substance is contained in an amount of 30 to 99% by mass based on the total amount of the magnetic substance and the nonmagnetic inorganic compound, thereby adjusting the strength of magnetization of the magnetic substance-containing resin carrier to prevent carrier adhesion, It is preferable when adjusting the specific resistance value of the magnetic substance-containing resin carrier.

In the magnetic substance-containing resin carrier, the magnetic substance is preferably magnetite fine particles or magnetic ferrite fine particles containing at least an iron element, and the nonmagnetic inorganic compound is hematite (α-Fe ₂ O ₃ ). Fine particles are more preferable for making the dispersibility in the carrier uniform and adjusting the magnetic properties and true specific gravity of the carrier.

  The number average particle diameter of the magnetic material is preferably 0.02 to 2 μm from the viewpoint of making the state of the particle surface of the magnetic carrier uniform. The nonmagnetic inorganic compound preferably has a number average particle diameter of 0.05 to 5 μm, and the nonmagnetic inorganic compound has a particle diameter of 1.1 times or more larger than that of the magnetic substance. It is preferable for increasing the surface resistance value.

  The surface of the magnetic substance-containing resin carrier is preferably coated with a coating material from the viewpoint of charge imparting properties and releasability. As a resin for forming the coating material, an insulating resin is preferably used. The insulating resin that can be used in this case may be a thermoplastic resin or a thermosetting resin.

  Specific examples of the resin for forming the coating material include thermoplastic resins such as polystyrene, polymethyl methacrylate, acrylic resins such as styrene-acrylic acid copolymers, styrene-butadiene copolymers, and ethylene. -Vinyl acetate copolymer, polyvinyl chloride, polyvinyl acetate, polyvinylidene fluoride resin, fluorocarbon resin, perfluorocarbon resin, solvent-soluble perfluorocarbon resin, polyvinyl alcohol, polyvinyl acetal, polyvinyl pyrrolidone, petroleum resin, cellulose, cellulose acetate, Cellulose derivatives such as cellulose nitrate, methylcellulose, hydroxymethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, novolak resin, low molecular weight polyethylene, saturated alkyl Riesuteru resin, polyethylene terephthalate, polybutylene terephthalate, polyarylates such aromatic polyester resins, polyamide resins, polyacetal resins, polycarbonate resins, polyethersulfone resins, polysulfone resins, polyphenylene sulfide resins, polyether ketone resins.

  Thermosetting resins include phenolic resins, modified phenolic resins, maleic resins, alkyd resins, epoxy resins, acrylic resins, or unsaturated polyesters obtained by polycondensation of maleic anhydride, terephthalic acid and polyhydric alcohols, urea Resin, melamine resin, urea-melamine resin, xylene resin, toluene resin, guanamine resin, melamine-guanamine resin, acetoguanamine resin, gliptal resin, furan resin, silicone resin, polyimide, polyamideimide resin, polyetherimide resin, polyurethane resin Is mentioned.

  The above-mentioned resins can be used alone or in combination. In addition, a curing agent or the like can be mixed with a thermoplastic resin and cured for use. As a particularly preferable form, it is preferable to use a resin having a higher release property for a toner having a small particle diameter and containing a release agent.

  Further, the coating material preferably contains conductive particles or charge controllable particles. Such a coating material contains the resin forming the coating material or the monomer forming the resin with conductive particles or charge controllable particles, and the resin or monomer is magnetized by an appropriate method. It is preferable to coat the body-containing resin carrier. These particles are important in terms of soft and quick charging to a toner having a small particle size and low temperature fixability.

The conductive particles preferably have a specific resistance of 1 × 10 ⁸ Ωcm or less, and more preferably have a specific resistance of 1 × 10 ⁶ Ωcm or less. Specifically, the conductive particles are preferably particles containing at least one kind of particles selected from carbon black, magnetite, graphite, zinc oxide, and tin oxide. In particular, as the particles having conductivity, carbon black having good conductivity is preferable in terms of improving the charge imparting property (rise of charge amount) to the toner.

  It is preferable that the conductive particles have a number average particle size of 1 μm or less in order to prevent the particles from falling off from the carrier and to function as a uniform conductive site.

The particles having charge controllability include organometallic complex particles, organometallic salt particles, chelate compound particles, monoazo metal complex particles, acetylacetone metal complex particles, hydroxycarboxylic acid metal complex particles, and polycarboxylic acid. Examples thereof include metal complex particles and polyol metal complex particles. A charge control agent dispersed in the toner particles may be used. In order to improve the charge imparting property to the toner, it is possible to use resin particles having a functional group or inorganic particles treated with a treatment agent having a functional group. preferable.

  Specifically, the particles having charge controllability include polymethyl methacrylate resin particles, polystyrene resin particles, melamine resin particles, phenol resin particles, nylon resin particles, silica particles, titanium oxide particles, and The particles preferably contain at least one kind of particles selected from alumina particles. Further, in the case of inorganic particles, it is preferable to use them after being treated with various coupling agents in order to develop charge controllability and conductivity.

  The particles having charge controllability preferably have a number average particle diameter of 0.01 to 1.5 μm from the viewpoint of functioning as a uniform charging site.

  The coating amount of the resin forming the coating material on the magnetic substance-containing resin carrier is 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the magnetic substance-containing resin core. And, it is preferable for enhancing the durability of the magnetic carrier. The blending amount of the conductive particles and charge controllable particles is preferably 0.1 to 30 parts by mass in total with respect to 100 parts by mass of the resin forming the coating material.

  Addition of more than 30 parts by mass of the above conductive particles or charge controllable particles makes it difficult for the particles to be dispersed in the resin forming the coating material, and the above particles are detached from the magnetic carrier. There is. In particular, when carbon black is added, the toner may be contaminated with carbon black or the member may be contaminated as the durability increases.

  The number average particle diameter of the magnetic carrier is preferably 15 to 60 μm (more preferably 25 to 50 μm) in relation to the weight average particle diameter of the toner. As a method for preparing the magnetic particles constituting the magnetic carrier so as to have the above-mentioned number average particle diameter, for example, classification can be performed by using a sieve. In particular, in order to classify with high accuracy, it is preferable to repeat a plurality of times using a sieve having an appropriate opening. It is also an effective means to use a mesh opening whose shape is controlled by plating or the like.

<Toner used in the replenishment developer of the present invention>
The production method of the toner used for the replenishment developer of the present invention is not particularly limited, and suspension polymerization method, emulsion polymerization method, association polymerization method, kneading and pulverization method and the like are used.
The toner of the present invention contains a binder resin for toner and a colorant, and the weight average particle diameter of the toner is preferably 4.0 to 8.0 μm, and preferably 4.0 to 7.0 μm. More preferably, it is 4.5-6.5 micrometers. When the weight average particle diameter of the toner is 4.0 to 8.0 μm, dot reproducibility and transfer efficiency can be sufficiently improved. The weight average particle diameter of the toner can be adjusted by classification of the toner particles at the time of production and mixing of classified products.

Preferable embodiments of the toner used for the replenishment developer of the present invention include the toner of the following first embodiment and the toner of the second embodiment.
The toner of the first aspect used in the developer for replenishment of the present invention is a toner having toner particles containing a resin mainly composed of a polyester unit and a colorant (hereinafter also referred to as “the toner of the first aspect”). ). “Polyester unit” means a part derived from polyester, and “resin mainly composed of polyester unit” means a resin in which many of the repeating units constituting the resin are repeating units having an ester bond. However, these will be described in detail later.

  The polyester unit is formed by condensation polymerization of ester monomers. Examples of the ester-based monomer include a polyhydric alcohol component and a carboxylic acid component such as a polyvalent carboxylic acid, a polyvalent carboxylic acid anhydride, or a polyvalent carboxylic acid ester having two or more carboxyl groups.

  The following are mentioned as a dihydric alcohol component among a polyhydric alcohol component. For example, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene ( 2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, poly Alkylene oxide adducts of bisphenol A such as oxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane; ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol 1,4-butanediol, neopentyl glycol, 1,4-bute Examples include diol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, and hydrogenated bisphenol A. .

  Examples of the trihydric or higher alcohol component among the polyhydric alcohol components include the following. For example, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol And glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene and the like.

  The following are mentioned as a carboxylic acid component which comprises a polyester unit. For example, aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid or anhydrides thereof; alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid or anhydrides thereof; alkyl groups having 6 to 12 carbon atoms And succinic acid or anhydride thereof substituted with an unsaturated dicarboxylic acid such as fumaric acid, maleic acid and citraconic acid, or an anhydride thereof.

Preferable examples of the resin having a polyester unit contained in the toner particles of the first aspect include the following. That is, a bisphenol derivative typified by the structure represented by the formula (1) as an alcohol component, a carboxylic acid component consisting of a divalent or higher carboxylic acid or an acid anhydride thereof, or a lower alkyl ester thereof (for example, fumaric acid, This is a polyester resin obtained by polycondensation of maleic acid, maleic anhydride, phthalic acid, terephthalic acid, dodecenyl succinic acid, trimellitic acid, pyromellitic acid) as carboxylic acid components. This polyester resin has good charging characteristics. The charging characteristics of this polyester resin work more effectively when used as a resin contained in a color toner contained in a two-component developer.

[In the formula, R is at least one selected from an ethylene group and a propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10. ]

  A preferred example of the resin having a polyester unit contained in the toner particles of the first aspect includes a polyester resin having a cross-linked site. The polyester resin having a crosslinking site can be obtained by subjecting a polyhydric alcohol and a carboxylic acid component containing a trivalent or higher polyvalent carboxylic acid to a condensation polymerization reaction. Examples of the trivalent or higher polyvalent carboxylic acid component include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 2,5,7. -Naphthalene tricarboxylic acid, 1,2,4,5-benzenetetracarboxylic acid, and acid anhydrides and ester compounds thereof. The content of the trivalent or higher polyvalent carboxylic acid component contained in the ester-based monomer to be polycondensed is preferably 0.1 to 1.9 mol% based on the total monomers.

Further, preferable examples of the resin having a polyester unit contained in the toner particles of the first aspect include (a) a hybrid resin having a polyester unit and a vinyl polymer unit, and (b) a hybrid resin and a vinyl system. A mixture of a polymer, (c) a mixture of a polyester resin and a vinyl polymer, (d) a mixture of a hybrid resin and a polyester resin, and (e) a mixture of a polyester resin, a hybrid resin, and a vinyl polymer. It is done.
The hybrid resin is formed by a transesterification reaction between a polyester unit and a vinyl polymer unit obtained by polymerizing a monomer component having a carboxylic ester group such as an acrylic ester. Examples of the hybrid resin include a graft copolymer or a block copolymer in which a vinyl polymer is a trunk polymer and a polyester unit is a branch polymer.

The vinyl polymer unit refers to a portion derived from a vinyl polymer. A vinyl polymer unit or a vinyl polymer is obtained by polymerizing a vinyl monomer described later.
The toner of the second aspect in the replenishment developer of the present invention is a toner having toner particles obtained from a direct polymerization method or in an aqueous medium (hereinafter also referred to as “the toner of the second aspect”). The toner according to the second aspect may be produced by a direct polymerization method, or may be produced by previously forming emulsified fine particles and then aggregating together with a colorant and a release agent. The toner having toner particles produced by the latter is also referred to as “a toner obtained from an aqueous medium” or “a toner obtained by an emulsion polymerization method”.

  The toner of the second aspect preferably has toner particles having a resin mainly composed of a vinyl resin, obtained by a direct polymerization method or an emulsion polymerization method. The vinyl resin that is the main component of the toner particles is produced by polymerization of a vinyl monomer. The following are mentioned as a vinyl-type monomer. For example, styrene monomers, acrylic monomers; methacrylic monomers; monomers of ethylenically unsaturated monoolefins; monomers of vinyl esters; monomers of vinyl ethers; monomers of vinyl ketones; monomers of N-vinyl compounds: other vinyl monomers Is mentioned.

The following are mentioned as a styrene-type monomer. For example, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene, 2,4- Dimethyl styrene, pn-butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl Styrene is mentioned.
The following are mentioned as an acryl-type monomer. For example, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, dimethylaminoethyl acrylate, acrylic Acrylic acid esters such as phenyl acid, and acrylic acid and acrylic acid amides.
Moreover, the following are mentioned as a methacrylic monomer. For example, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, Examples include methacrylic acid esters such as diethylaminoethyl methacrylate, methacrylic acid and methacrylic acid amides.
Examples of the monomer of the ethylenically unsaturated monoolefins include ethylene, propylene, butylene, and isobutylene.
Examples of vinyl ester monomers include vinyl acetate, vinyl propionate, and vinyl benzoate.
Examples of vinyl ether monomers include vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether.
Examples of the vinyl ketone monomers include vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone.
Examples of the monomer of the N-vinyl compound include N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, and N-vinyl pyrrolidone.
Other vinyl monomers include acrylic acid derivatives or methacrylic acid derivatives such as vinyl naphthalenes, acrylonitrile, methacrylonitrile and acrylamide.
These vinyl monomers can be used alone or in combination of two or more.

The following are mentioned as a polymerization initiator used when manufacturing a vinyl-type resin. For example, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2 ′ -Azo or diazo polymerization initiators such as azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butylhydro Peroxide, di-t-butyl peroxide, dicyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis (4,4-t-butylperoxycyclohexyl) propane, tris- (t-butylperoxy) Peracids such as triazine Compound initiators and peroxides in the side chain; persulfates such as potassium persulfate and ammonium persulfate; and hydrogen peroxide.
Examples of radically polymerizable trifunctional or higher polymerization initiators include tris (t-butylperoxy) triazine, vinyltris (t-butylperoxy) silane, 2,2-bis (4,4-di-). t-butylperoxycyclohexyl) propane, 2,2-bis (4,4-di-t-amylperoxycyclohexyl) propane, 2,2-bis (4,4-di-t-octylperoxycyclohexyl) propane And a radical polymerizable polyfunctional polymerization initiator such as 2,2-bis (4,4-di-t-butylperoxycyclohexyl) butane.

Both the toner of the first aspect of the present invention and the replenishment developer using the toner of the second aspect are preferably used in an electrophotographic process employing oilless fixing. Therefore, the toner (the toner of the first aspect and the toner of the second aspect) used for the replenishment developer of the present invention preferably contains a release agent.
Examples of the release agent include the following. For example, low molecular weight polyethylene, low molecular weight polypropylene, polyolefin copolymer, polyolefin wax, microcrystalline wax, paraffin wax, aliphatic hydrocarbon wax such as Fischer-Tropsch wax; oxidation of aliphatic hydrocarbon wax such as oxidized polyethylene wax Or block copolymers thereof; waxes based on fatty acid esters such as carnauba wax, montanate wax, and behenyl behenate; partially or fully deoxidized fatty acid esters such as deoxidized carnauba wax The thing which was done is mentioned.

Suitable release agents include hydrocarbon waxes and paraffin waxes. The toner has one or more endothermic peaks in the temperature range of 30 to 200 ° C. in the endothermic curve of the toner in differential scanning calorimetry measurement, and the maximum endothermic peak temperature in the endothermic peak is 50 to 110 ° C. The toner can have good low-temperature fixability and durability.
Examples of the differential scanning calorimetric analyzer include DSC-7 manufactured by PerkinElmer, DSC2920 manufactured by TA Instruments, Q1000 manufactured by TA Instruments, and the like. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. An aluminum pan is used as a measurement sample, and an empty pan is set for control and measured.
The content of the release agent in the toner contained in the replenishment developer of the present invention is preferably 1 to 15 parts by mass with respect to 100 parts by mass of the binder resin in the toner particles, and is 3 to 10 parts by mass. More preferably. When the content of the release agent is 1 to 15 parts by mass, good transferability can be exhibited during oilless fixing.

  The toner used in the present invention may contain a charge control agent. Examples of the charge control agent include organometallic complexes, metal salts, and chelate compounds. Examples of the organometallic complex include a monoazo metal complex, an acetylacetone metal complex, a hydroxycarboxylic acid metal complex, a polycarboxylic acid metal complex, and a polyol metal complex. Other examples include carboxylic acid derivatives such as metal salts of carboxylic acids, carboxylic acid anhydrides, and esters, and condensates of aromatic compounds. Also, phenol derivatives such as bisphenols and calixarenes can be used as the charge control agent. The charge control agent contained in the toner of the present invention is preferably a metal compound of an aromatic carboxylic acid from the viewpoint of improving the charge rising of the toner.

  The content of the charge control agent in the toner used in the replenishment developer of the present invention is preferably 0.1 to 10.0 parts by mass with respect to 100 parts by mass of the binder resin, and 0.2 to 5. More preferably, it is 0 parts by mass. Since the toner has a charge control agent of 0.1 to 10.0 parts by mass with respect to 100 parts by mass of the binder resin in the toner particles, the charge amount of the toner can be controlled in a wide range of environments from high temperature and high humidity to low temperature and low humidity. Change can be reduced.

  The triboelectric charge amount of the toner used in the replenishment developer of the present invention is not particularly limited, but the absolute value is preferably 25 to 45 mC / Kg.

The toner used in the replenishment developer of the present invention has a colorant. Here, the colorant may be a pigment or a dye, or a combination thereof.
Examples of the dye include the following. For example, C.I. I. Direct Red 1, C.I.
I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Modern Tread 30, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Modern Blue 7, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. Basic green 6 is listed.

  Examples of the pigment include the following. For example, Mineral Fast Yellow, Navel Yellow, Naphthol Yellow S, Hansa Yellow G, Permanent Yellow NCG, Tartrazine Lake, Molybdenum Orange, Permanent Orange GTR, Pyrazolone Orange, Benzidine Orange G, Permanent Red 4R, Watching Red Calcium Salt, Eosin Lake , Brilliant Carmine 3B, Manganese Purple, Fast Violet B, Methyl Violet Lake, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue BC, Chrome Green, Pigment Green B, Malachite Green Lake And Final Yellow Green G.

  In addition, when the replenishment developer of the present invention is used as a full-color image forming developer, the toner can contain a magenta color pigment. Examples of the magenta coloring pigment include the following. For example, C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 163, 202, 206, 207, 209, 238, C.I. I. Pigment violet 19, C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35 are mentioned.

  The toner particles may contain only a magenta color pigment. However, when a dye and a pigment are combined, the clarity of the developer can be improved and the image quality of a full-color image can be improved. Examples of the magenta dye include the following. For example, C.I. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121, C.I. I. Disper thread 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27, C.I. I. Oil-soluble dyes such as Disperse Violet 1; I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. I. Basic dyes such as basic violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, and 28 may be mentioned.

  Examples of the color pigment for cyan include the following. For example, C.I. I. Pigment Blue 2, 3, 15, 15: 1, 15: 2, 15: 3, 16, 17; I. Acid Blue 6; I. Examples include Acid Blue 45 or a copper phthalocyanine pigment in which 1 to 5 phthalimidomethyl groups are substituted on the phthalocyanine skeleton.

  Examples of the color pigment for yellow include the following. For example, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 65, 73, 74, 83, 93, 97, 155, 180, C. I. Bat yellow 1, 3, and 20 are mentioned.

Examples of the black pigment include carbon powder such as furnace black, channel black, acetylene black, thermal black, and lamp black, and magnetic powder such as magnetite and ferrite.

  Further, the color may be adjusted by combining a magenta dye and a pigment, a yellow dye and a pigment, a cyan dye and a pigment, and the carbon black may be used in combination.

  The content of the colorant in the toner used in the replenishment developer of the present invention is preferably 1 to 15 parts by mass, and 3 to 12 parts by mass with respect to 100 parts by mass of the binder resin in the toner particles. More preferably, the amount is 4 to 10 parts by mass. When the content of the colorant is 1 to 15 parts by mass with respect to the colorant in the toner particles, the transparency is maintained, and in addition, the reproducibility of intermediate colors as typified by human skin color is improved. . Furthermore, the stability of the charging property of the toner is improved, and a low-temperature fixability can be obtained.

  The toner used for the replenishment developer of the present invention may be externally added with external additives which are fine particles, in addition to the inorganic fine particles previously mixed with the magnetic carrier particles. By externally adding fine particles, fluidity and transferability can be improved. The external additive externally added to the toner particle surface preferably contains inorganic fine particles of titanium oxide, alumina oxide, and silica fine particles. The surface of the inorganic fine particles contained in the external additive is preferably subjected to a hydrophobic treatment. The hydrophobizing treatment is preferably performed by a coupling agent such as various titanium coupling agents and silane coupling agents; fatty acids and metal salts thereof; silicone oils; or a combination thereof.

  Examples of the titanium coupling agent for hydrophobizing the inorganic fine particles contained in the external additive include the following. For example, tetrabutyl titanate, tetraoctyl titanate, isopropyl triisostearoyl titanate, isopropyl tridecyl benzene sulfonyl titanate, bis (dioctyl pyrophosphate) oxyacetate titanate can be mentioned.

  Moreover, the following are mentioned as a silane coupling agent. For example, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) ) Γ-aminopropyltrimethoxysilane hydrochloride, hexamethyldisilazane, methyltrimethoxysilane, butyltrimethoxysilane, isobutyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane , Phenyltrimethoxysilane, o-methylphenyltrimethoxysilane, and p-methylphenyltrimethoxysilane.

  Examples of the fatty acid for hydrophobizing the inorganic fine particles include the following. For example, long chain fatty acids such as undecyl acid, lauric acid, tridecyl acid, dodecyl acid, myristic acid, palmitic acid, pentadecylic acid, stearic acid, heptadecylic acid, arachidic acid, montanic acid, oleic acid, linoleic acid, arachidonic acid It is done. Examples of the metal of the fatty acid metal salt include zinc, iron, magnesium, aluminum, calcium, sodium, and lithium.

  Examples of the silicone oil for performing the hydrophobizing treatment include dimethyl silicone oil, methylphenyl silicone oil, and amino-modified silicone oil.

  The hydrophobization treatment is preferably performed by adding 1 to 30% by mass (more preferably 3 to 7% by mass) of the hydrophobizing agent to the inorganic fine particles and coating the inorganic fine particles with respect to the inorganic fine particles. .

  The degree of hydrophobicity of the hydrophobized inorganic fine particles is not particularly limited. For example, the methanol wettability of the treated inorganic fine particles is preferably 40 to 95. Methanol wettability refers to wettability with methanol.

  The content of the external additive in the toner is preferably 0.1 to 5.0% by mass, and more preferably 0.5 to 4.0% by mass. The external additive may be a combination of a plurality of types of fine particles.

In the replenishment developer of the present invention, the inorganic fine particles are preferably mixed in advance in a mass ratio of 0.01 to 10 parts by mass, more preferably 0.05 to 100 parts by mass with respect to 100 parts by mass of the magnetic carrier. 5 parts by mass, more preferably 0.05 to 3 parts by mass is preferably mixed.

When the inorganic fine particles mixed in advance with the magnetic carrier have a mass ratio of less than 0.01 parts by mass with respect to 100 parts by mass of the magnetic carrier, image flow may occur and image defects such as fogging may occur. is there. This is because the amount of inorganic fine particles supplied into the developing device together with the carrier in the replenishing developer is reduced, the amount of inorganic fine particles supplied from the developing device to the polishing site is insufficient, and a sufficient polishing effect is hardly exhibited. This is thought to be due to the occurrence of image flow.
Further, when the inorganic fine particles mixed in advance with the magnetic carrier have a mass ratio of the inorganic fine particles larger than 10 parts by mass with respect to 100 parts by mass of the magnetic carrier, member contamination or charge-up may occur. This is because, in the step of mixing the carrier and the inorganic fine particles in advance, uniform mixing cannot be performed, the free inorganic fine particles increase, and the free inorganic fine particles are scattered to cause member contamination. It is considered that the fine particles themselves behave like a carrier with respect to the toner, and the charge amount of the toner increases.

  As described above, the replenishment developer used in the present invention is characterized in that the inorganic fine particles and the magnetic carrier are mixed in advance and then mixed with toner. By mixing the inorganic fine particles and the magnetic carrier in advance, a high-definition image can be stably obtained over a long period of use. This is considered to be because it is possible to suppress fluctuations in the charging characteristics of the developer that occur when the inorganic fine particles are externally added to the toner. Further, when the inorganic fine particles and the magnetic carrier are not mixed in advance, it is impossible to achieve both high durability stability and high image quality in long-term use. This is considered to be because it becomes difficult to suppress fluctuations in the charging characteristics of the developer that occur when the above-described inorganic fine particles are externally added to the toner.

The replenishment developer of the present invention is characterized in that the toner is mixed in a mass ratio of 2 to 50 parts by mass with respect to 1 part by mass of the magnetic carrier, preferably 5 to 25 parts by mass. More preferably, it is preferably mixed at a mass ratio of 10 to 20 parts by mass.
By using in this range, it is possible to maintain the performance of a stable replenishment developer for a long period of time, and there is little fluctuation in toner chargeability, good dot reproducibility, and an image with little fogging can be obtained. it can. Further, there is a merit that replenishability from the replenishment developer container to the developing device is good.

  When the toner mass ratio is less than 2 parts by mass, the amount of toner to be replenished becomes relatively small, the toner charge amount becomes non-uniform, and image defects such as white streaks occur. On the other hand, when the mass ratio of the toner exceeds 50 parts by mass, the toner and the magnetic carrier are unevenly distributed in the replenishment developer container, and it is difficult to obtain charging stability. In addition, when the amount of carrier to be replenished is insufficient and used over a long period of time, the performance of the replenishing developer is lowered, the durability is deteriorated, the dot reproducibility is also deteriorated, and the fog is increased.

  Further, the development method using the replenishment developer of the present invention is a replenishment developer containing at least toner, inorganic fine particles and a magnetic carrier, and develops the replenishment developer while replenishing the developer. In addition, the two-component developing method is characterized in that at least the excess carrier inside the developing device is discharged from the developing device.

<Developing Method Using Replenishment Developer of the Present Invention>
The developer for replenishment according to the present invention forms an electrostatic image on an electrostatic charge image carrier, forms a magnetic brush from toner and a magnetic carrier on the developer carrier that contains magnetic field generating means, and develops the developer carrier. A two-component developing method for developing an electrostatic image with a magnetic brush formed thereon to form a toner image on the electrostatic image carrier, wherein the magnetic brush is based on 100 parts by mass of a magnetic carrier. The toner is used in a two-component developing method having 5 to 20 parts by mass of toner, supplying a developer for replenishment to the developing device, and discharging the excess magnetic carrier inside the developing device from the developing device.

An image forming method using the replenishment developer of the present invention will be described. FIG. 1 is a schematic configuration diagram of an electrophotographic full-color image forming apparatus equipped with a rotary rotating developing device.
First, the surface of the electrostatic latent image carrier 1 is uniformly charged negatively by the charging device 15. Next, the exposure device 14 performs image exposure corresponding to the first color, for example, a yellow image, and an electrostatic latent image corresponding to the yellow image is formed on the surface of the photoreceptor 1 such as an electrostatic latent image carrier. .
The developing device 13 has a rotational movement type, and before the leading edge of the electrostatic latent image corresponding to the yellow image reaches the developing position, the yellow developing device faces the photosensitive member 1 and thereafter the magnetic brush is statically moved. The electrostatic latent image is rubbed to form a yellow toner image on the photoreceptor.

  The developing device used for the above development has a developing device. The developing device is provided with a developing sleeve, a supply roll, a magnet roll, a regulating member, and a scraper. FIG. 2 is a schematic configuration diagram of the developing devices 2, 3, 4, and 5 of FIG. The flow of transport until the developer in the developing device is developed will be described with reference to FIG.

  The developing sleeve 6 includes a fixed magnet roll 8 and is driven and rotated while maintaining a predetermined developing interval with the peripheral surface of the photoreceptor 1. The developing sleeve 6 and the photoreceptor 1 may be in contact with each other. The regulating blade 7 such as a regulating member has rigidity and magnetism, and is pressed against the developing sleeve 6 with a predetermined load in a state where the developer is not present, or at a predetermined interval with the developing sleeve 6. There are various things. The developer conveying screws 10 and 11 such as a pair of developer agitating / conveying members have a screw structure, convey and circulate the developer in opposite directions, sufficiently agitate and mix the toner and the magnetic carrier, and develop as a developer. It acts to send to the sleeve 6. The magnet roll 8 is composed of, for example, a magnet having four magnetic poles having the same magnetic force in which N poles and S poles are alternately arranged at equal intervals, or one pole is omitted to form five poles. It may be included in a fixed state. The latter is preferable in order to form a repulsive magnetic field at the portion in contact with the scraper and facilitate the peeling of the developer.

The two developer conveying screws 10 and 11 are members that also serve as stirring members that rotate in directions opposite to each other. The replenishment developer replenished from the replenishment developer accommodating device 9 is conveyed by the thrust of the agitating screw, and is made into a homogeneous two-component developer that is triboelectrically charged by the mixing action of the toner and the magnetic carrier. . Then, the developer is layered on the peripheral surface of the developing sleeve 6. The developer on the surface of the developing sleeve 6 such as a developer carrying member forms a uniform layer by a double-structured regulating blade 7 made of a nonmagnetic material and a magnetic material provided facing the magnetic pole of the magnet roll 8. . The uniformly formed developer layer is
The latent image on the peripheral surface of the photoreceptor 1 is developed with a magnetic brush composed of toner and magnetic carrier to form a toner image. At this time, it is important that the magnetic brush has 5 to 20 parts by mass of toner with respect to 100 parts by mass of the magnetic carrier.

  In FIG. 1, a transfer material 12 such as paper or a transparent sheet is conveyed from a paper feed tray 26 or 27 by a feed roller 28 or 29 and once blocked by a registration roller 25, then a predetermined timing is reached. Is sent to the transfer drum 24. The transferred transfer material 12 is electrostatically held on the transfer drum 24 by the suction device 32 and the opposing roller 30, and is conveyed to a transfer region where the transfer drum 24 and the photosensitive member 1 face each other. Therefore, the transfer material 12 is in close contact with the yellow toner image on the photoreceptor 1, and the yellow toner image is transferred onto the transfer material 12 by the action of the transfer device 31, and the transfer drum 24 holds the transfer material 12. Prepare for the next step.

  After the yellow toner has been transferred, the photosensitive member 1 is subjected to a pre-cleaning process as necessary, and then neutralized with a static eliminating corotron, and the cleaning device 18 scrapes off the yellow toner remaining on the surface. Further, the charge remaining on the surface of the photoreceptor 1 is neutralized by the neutralization device 16.

  Next, for the image forming process of the second color, for example, magenta, the surface of the photoconductor 1 is uniformly charged negatively by a charging roller 15 such as a charger, and a magenta image is formed by an exposure device 14. The image exposure corresponding to is performed. As a result, an electrostatic latent image corresponding to the magenta image is formed on the surface of the photoreceptor 1. Further, after the formation of the yellow toner layer is completed, the developing device 13 is switched so that the magenta developer is opposed to the photosensitive member 1, and the electrostatic latent image corresponding to the magenta image It is developed with a magnetic brush. Then, the transfer material 12 held on the transfer drum 24 is conveyed again to the transfer area, and the magenta toner is multiple-transferred onto the yellow toner this time by the action of the transfer device 31.

After the transfer of the magenta toner, the photoreceptor 1 is subjected to cleaning of residual toner on the surface and charge removal from the residual charge in the same manner as in the yellow image forming process. On the other hand, the transfer material that has completed the transfer of the magenta toner is prepared for the next step while being held on the transfer drum 24.
Thereafter, as in the magenta image forming process, an image forming process for the third color, for example, cyan is performed, and finally, an image forming process for the fourth color, for example, black is performed. In the final black image forming process, the transfer material is conveyed differently from the processes up to the third color. In other words, the transfer material 12 that has finished transferring the fourth color is separated from the transfer drum 24 by a discharge finger (not shown) at the tip of the static elimination device 19 and the conveyance guide member 20, and the multiple toner image is transferred to the transfer material by the fixing device 21. Are transferred to the outside of the image forming apparatus.

Further, after the transfer drum 24 has been separated from the transfer material, the surface of the transfer drum 24 is neutralized by the neutralization devices 22 and 33, the surface is then cleaned by the cleaning device 23, and the next transfer material 12 is awaited.
When the copying operation as described above is repeated, the toner in the developer stored in the developing tank 17 in the developing unit of FIG. To go. This change in toner density is feedback controlled by a toner density sensor (not shown) provided in the developing tank 17 so that the toner density always falls within an appropriate range necessary for development. By the above control, the toner is supplied from the replenishment port of the replenishment developer accommodating device 9 to the developing tank 17 in the developing device.

On the other hand, the carrier in the developer in the developing tank 17 is not consumed by the development, and is stirred together with the toner in the developing tank 17, the magnetic force of the magnet roll, and the electrostatic latent image carrier 1. The surface is gradually contaminated and deteriorates due to the influence of contact with the surface. As the carrier deteriorates in this way, a predetermined charge amount cannot be imparted to the toner, resulting in a reduction in image quality. Therefore, it is necessary to replace the deteriorated carrier which is not consumed in the developing device with a new carrier. In FIG. 1, as means for replenishing a new carrier into the developing device, a replenishment toner and a predetermined amount of carrier are supplied in a replenishment developer accommodating device 9 for replenishing toner consumed by development. Add the replenishment developer mixed with. Then, the developing devices 2, 3, 4, and 5 are replenished from the replenishing port of the replenishing developer accommodating device 9. The excess developer is discharged from the developer-side developer discharge port.

Next, the replacement of the developer using the rotational movement in the rotating developing device 13 shown in FIG. 1 will be described with reference to FIGS.
The developer overflowing from the developer discharge port 34 on the developing device side provided in the developing device 2 at a position where the developing device 2 faces the photoreceptor 1 and performing the developing operation is moved into the communication pipe 36 by the rotating operation. To move. Then, the toner is discharged from a developer recovery port 35 provided on the rotation center shaft of the rotary developer switching device.

As a developing method using the magnetic carrier of the present invention, specifically, an AC voltage is applied to the developer carrying member to form an alternating electric field in the developing region, while the magnetic brush contacts the photoreceptor 1. It is preferable to perform development in the state where The distance between the developing sleeve 6 and the photosensitive member 1 (SD distance) is preferably 100 to 1000 μm in terms of preventing carrier adhesion and improving dot reproducibility. If it is smaller than 100 μm, the supply of the developer tends to be insufficient and the image density tends to be low. On the other hand, when the thickness exceeds 1000 μm, the magnetic lines of force from the magnetic pole S1 spread and the density of the magnetic brush is lowered, so that the dot reproducibility is inferior or the force for restraining the magnetic coat carrier is weakened and the carrier adheres easily.

  The voltage between the peaks of the alternating electric field is preferably 300 to 3000 V, and the frequency is 500 to 10000 Hz, preferably 1000 to 7000 Hz, which can be appropriately selected depending on the process. In this case, the waveform of the AC bias for forming the alternating electric field includes a triangular wave, a rectangular wave, a sine wave, or a waveform with a changed duty ratio. In order to cope with the change in the formation speed of the toner image sometimes, it is preferable to perform development by applying a developing bias voltage (intermittent alternating voltage) having a discontinuous AC bias voltage to the developer carrier. . When the applied voltage is lower than 300 V, it is difficult to obtain a sufficient image density, and the fog toner in the non-image portion may not be recovered well. If the voltage exceeds 3000 V, the latent image may be disturbed via the magnetic brush, leading to a reduction in image quality.

By using a two-component developer with well-charged toner, the anti-fogging voltage (Vback) can be lowered and the primary charge of the photoreceptor can be lowered, thus extending the life of the photoreceptor. it can. Vback is 200 V or less, more preferably 150 V or less, although it depends on the development system. The contrast potential is preferably 100 to 400 V so that a sufficient image density is obtained.
On the other hand, when the frequency is lower than 500 Hz, although related to the process speed, when the toner in contact with the electrostatic latent image carrier is returned to the developing sleeve, sufficient vibration is not applied and fogging is likely to occur. If it exceeds 10,000 Hz, the toner cannot follow the electric field, and the image quality is likely to deteriorate.

The contact width (development contact portion) of the magnetic brush on the developing sleeve 6 with the photosensitive member 1 is 3 to 8 mm in order to achieve a sufficient image density, excellent dot reproducibility and development without carrier adhesion. Preferably there is. If the developing contact area is narrower than 3 mm, it is difficult to satisfactorily satisfy the sufficient image density and dot reproducibility. If the developing contact area is larger than 8 mm, developer packing occurs and the operation of the machine is stopped. It may be difficult to sufficiently suppress adhesion. As a method of adjusting the developing contact portion, the contact width is adjusted by adjusting the distance between the regulating blade 7 and the developing sleeve 6 or by adjusting the distance between the developing sleeve 6 and the photosensitive member 1 (SD distance). There is a method of appropriately adjusting.

FIG. 4 is a schematic diagram in which the image forming method of the present invention is applied to a full-color image forming apparatus. This apparatus also does not have an independent cleaning means for collecting and storing the transfer residual toner remaining on the photoreceptor, and the toner remaining on the image carrier after the developing means transfers the toner image onto the transfer material. The development simultaneous cleaning method for recovering the water is performed.
The amount of the carrier increased by the carrier contained in the replenishment developer overflows and is taken into the developer collection auger and conveyed to the replenishment developer container or another collection container.

The full-color image forming apparatus main body is provided with a first image forming unit Pa, a second image forming unit Pb, a third image forming unit Pc, and a fourth image forming unit Pd. It is formed on a transfer material through development and transfer processes.
The configuration of each image forming unit provided in the image forming apparatus will be described by taking the first image forming unit Pa as an example.

  The first image forming unit Pa includes a photoreceptor 61a having a diameter of 30 mm as an electrostatic latent image carrier, and the photoreceptor 61a is rotationally moved in the direction of arrow a. A charging roller 62a such as a primary charger serving as a charging unit is disposed such that a charging magnetic brush formed on the surface of a sleeve having a diameter of 16 mm contacts the surface of the photoreceptor 61a. The exposure light 67a is irradiated by an exposure device (not shown) in order to form an electrostatic latent image on the photoreceptor 61a whose surface is uniformly charged by the charging roller 62a. A developing device 63a as developing means for developing the electrostatic latent image carried on the photoreceptor 61a to form a color toner image holds color toner. The transfer blade 64a as a transfer means transfers the color toner image formed on the surface of the photoreceptor 61a onto the surface of the transfer material (recording material) conveyed by the belt-like transfer material carrier 68. The transfer blade 64 a is in contact with the back surface of the transfer material carrier 68 and can apply a transfer bias.

  The first image forming unit Pa uniformly charges the photosensitive member 61a with the primary charger 62a, then forms an electrostatic latent image on the photosensitive member with the exposure light 67a from the exposure device, and electrostatically develops with the developing device 63a. The latent image is developed using color toner. The developed toner image is transferred from a transfer blade 64a that abuts on the back side of a belt-like transfer material carrier 68 that carries and conveys the transfer material at a first transfer portion (contact position between the photosensitive member and the transfer material). Is applied to the surface of the transfer material.

  When the toner is consumed by the development and the T / C ratio decreases, the decrease is detected by the toner concentration detection sensor 85 that measures the change in the magnetic permeability of the developer using the inductance of the coil, and the amount of consumed toner is calculated. Accordingly, the replenishment developer is replenished from the replenishment developer container 65a. The toner concentration detection sensor 85 has a coil (not shown) inside.

This image forming apparatus has the same configuration as that of the first image forming unit Pa, and the second image forming unit Pb, the third image forming unit Pc, and the fourth image forming unit having different color toner colors held in the developing device. The image forming unit Pd is provided with four image forming units. For example, yellow toner is used for the first image forming unit Pa, magenta toner is used for the second image forming unit Pb, cyan toner is used for the third image forming unit Pc, and black toner is used for the fourth image forming unit Pd. Accordingly, the transfer of each color toner onto the transfer material is sequentially performed at the transfer portion of each image forming unit. In this step, the color toners are superimposed on each other by moving the transfer material once on the same transfer material while aligning the registration. When the transfer is completed, the transfer material is separated from the transfer material carrier 68 by the separation charger 69. The Thereafter, the image is sent to the fixing device 70 by a conveying means such as a conveying belt, and a final full-color image is obtained by only one fixing.

The fixing device 70 includes a pair of a fixing roller 71 having a diameter of 40 mm and a pressure roller 72 having a diameter of 30 mm. The fixing roller 71 includes heating means 75 and 76 therein.
The unfixed color toner image transferred onto the transfer material passes through the pressure contact portion between the fixing roller 71 and the pressure roller 72 of the fixing device 70 and is fixed onto the transfer material by the action of heat and pressure. The

In FIG. 4, a transfer material carrier 68 is an endless belt-like member, and this belt-like member is moved in the direction of arrow e by 80 drive rollers. In addition, a transfer belt cleaning device 79 and a belt driven roller 81 have a belt static eliminator 82, and the pair of registration rollers 83 are for conveying the transfer material in the transfer material holder to the transfer material carrier 68. .
As the transfer means, in place of the transfer blade that contacts the back side of the transfer material carrier, contact transfer means that can contact the back side of the transfer material carrier and directly apply the transfer bias, such as a roller-like transfer roller, can be used. It is possible to use.

Further, a non-contact transfer unit that performs transfer by applying a transfer bias from a corona charger disposed in a non-contact manner on the back side of a transfer material carrier that is generally used instead of the contact transfer unit described above. It is also possible to use.
However, it is more preferable to use the contact transfer means in that the amount of ozone generated when applying the transfer bias can be controlled.

  Next, the flow of the developer in the image forming apparatus using the replenishment developer will be described with reference to FIG. As the electrostatic latent image on the photoreceptor is developed with toner, the toner in the developing device 102 is consumed. A toner density detection sensor (not shown) detects that the toner in the developing device is low, and the replenishment developer is supplied from the replenishment developer container 101 to the developing device 102. The excess magnetic carrier in the developing device moves to the developer recovery container 104. The developer collection container 104 may collect the toner collected by the cleaning device 103 together.

<Method for Producing Replenishment Developer of the Present Invention>
Further, the present invention is used for a two-component developing method in which an electrostatic image is developed while replenishing the replenishing developer to the developing device, and at least the excess carrier inside the developing device is discharged from the developing device. A method for producing a replenishment developer comprising:
The inorganic fine particles have a number average particle diameter (D1) of 50 to 300 nm,
The present invention relates to a method for producing a replenishing developer, wherein the inorganic fine particles and the magnetic carrier are mixed in advance and then mixed with toner.

Examples of the method of mixing the inorganic fine particles and the magnetic carrier in advance include, for example, a double-con mixer (manufactured by Fuji Powder Co.), a V-type mixer (manufactured by Fuji Powder Co., Ltd.), a drum mixer (manufactured by Seiwa Giken Co., Ltd.), a super Commonly used mixing devices such as a mixer (manufactured by Kawata), a Henschel mixer (manufactured by Mitsui Miike Chemical Co., Ltd.), and a nauter mixer (manufactured by Hosokawa Micron) can be used. Among the above mixing devices, for example, when a container rotating mixer is used, the peripheral speed of rotation in the mixing of the magnetic carrier and the inorganic fine particles is generally in the range of 20 to 80 m / min depending on their mixing capacity. Something is preferable. The rotational peripheral speed is obtained from the number of rotations per unit time, with the rotation radius being the distance from the axis to the farthest part of the container around the axis that rotates the container. When the rotational peripheral speed exceeds 80 m / min, the mixing effect becomes unnecessarily large, and the wear of the carrier surface and the pulverization of the inorganic fine particles progress, which is not preferable. In addition, when the rotational peripheral speed is lower than 20 m / min, the inorganic fine particles are not uniformly adhered to the surface of the magnetic carrier, the amount of free inorganic fine particles increases, and segregation of the inorganic fine particles occurs when a replenishment developer is used. . In addition, when coarse inorganic fine particles remain without being crushed and used as a replenishment developer, the coarse particles may be sandwiched between the developing sleeve and the blade, causing streaks in the image.

  As described above, the inorganic fine particles and the magnetic carrier are mixed in advance, and then the replenishment developer is adjusted. A predetermined amount of the toner and the magnetic carrier previously mixed with the inorganic fine particles are weighed and mixed by a mixer. In addition, as conditions at the time of mixing with a mixer, it is preferable to carry out under normal temperature normal humidity. As an example of a mixing apparatus, for example, a double-con mixer (manufactured by Fuji Powder Corporation), a V-type mixer (manufactured by Fuji Powder Corporation), a drum mixer (manufactured by Seiwa Giken Co., Ltd.), a super mixer (manufactured by Kawata Corporation), a Henschel mixer (Mitsui Miike Kako Co., Ltd.), Nauta mixer (Hosokawa Micron Co., Ltd.), etc. can be mentioned. Among these, the V-type mixer is preferable in consideration of the dispersibility of the magnetic carrier and the charge rising of the toner.

<About the electrophotographic photosensitive member used in the present invention>
The structure of the electrostatic latent image bearing member may be the same as that of a photoreceptor used in an image forming apparatus, and is a photoreceptor having improved surface resistance, such as amorphous silicon, with improved wear resistance. An organic photoconductor (a-Si photoconductor), an organic material having a protective layer in the order of a conductive layer, an undercoat layer, a charge generation layer, a charge transport layer, and an outermost layer on a conductive substrate such as aluminum or SUS. Examples include a photoreceptor.

  An amorphous silicon photoreceptor is a photoreceptor having a photosensitive layer formed of a non-single crystal material (a-Si) having silicon atoms as a base. a-Si includes other atoms such as hydrogen atoms, halogen atoms, carbon atoms, oxygen atoms, atoms classified into Group 3B of the periodic table such as boron, and atoms classified into Periodic Table 5B such as nitrogen. May be included. In addition, the photosensitive layer is preferably configured by stacking a plurality of layers having different functions. As such a plurality of layers, a photoconductive layer composed of a lower blocking layer, a charge transport layer, a charge generation layer, and the like, a buffer layer, a surface layer, and the like can be exemplified.

  The amorphous silicon-based photoconductor has a surface layer formed of hydrogenated amorphous carbon on the outermost surface from the viewpoint of improving the hardness of the photoconductor surface and improving the lubricity of the photoconductor surface. preferable. Hydrogenated amorphous carbon is a non-single crystal material containing a carbon atom as a base (a-C: H), and contains other atoms similar to the above-described a-Si. There may be. Note that a-C: H mainly represents amorphous carbon having intermediate properties between graphite and diamond, but a-C: H partially contains microcrystals and polycrystals. Also good.

  The amorphous silicon photoconductor including the surface layer can be manufactured by a conventionally known method. As such a manufacturing method, for example, a conductive substrate is installed in the system, and A manufacturing method (for example, plasma CVD method) in which an atom supply gas (raw material gas) containing the generated atoms is introduced into the system, plasma is generated in the system to decompose the raw material gas, and atoms are deposited on a conductive substrate. It can be illustrated. The film thickness and strength of the formed photosensitive layer (including the surface layer) can be adjusted by the concentration of the raw material gas, the high frequency power used for the discharge, or the like. The source gas may be diluted with hydrogen or a rare gas (inert gas).

  An organic photoreceptor having a protective layer, a conductive layer, an undercoat layer, a charge generation layer, and a charge transport layer may be usually used for a photoreceptor, and a charge generation layer and a charge transport layer are sequentially provided on a support. Furthermore, a protective layer is provided on the outermost surface. Further, a binder layer and an undercoat layer for the purpose of preventing interference fringes may be provided between the support and the charge generation layer.

  The support itself can be conductive, for example, aluminum, aluminum alloy, or stainless steel. In addition, aluminum, aluminum alloy, or indium oxide-tin oxide alloy is formed by vacuum deposition. The above-mentioned support, plastic, and conductive fine particles (for example, carbon black, tin oxide, titanium oxide, and silver particles) having a layer formed thereon are impregnated into plastic or paper together with an appropriate binder resin, conductive binder A plastic having a resin can be used.

  Further, a binder layer (adhesive layer) having a barrier function and an adhesive function can be provided between the support and the photosensitive layer. The binder layer is used to improve the adhesion of the photosensitive layer, improve the coatability, protect the support, cover defects on the support, improve the charge injection from the support, and protect against electrical breakdown of the photosensitive layer. It is formed. The binder layer can be formed of casein, polyvinyl alcohol, ethyl cellulose, ethylene-acrylic acid copolymer, polyamide, modified polyamide, polyurethane, gelatin, aluminum oxide, or the like. The film thickness of the binder layer is preferably 5 μm or less, and particularly preferably 0.1 to 3 μm.

  Examples of the charge generating material used in the present invention include (1) azo pigments such as monoazo, disazo and trisazo, (2) phthalocyanine pigments such as metal phthalocyanine and nonmetal phthalocyanine, and (3) indigo materials such as indigo and thioindigo. Pigments, (4) perylene pigments such as perylene anhydride and perylene imide, (5) polycyclic quinone pigments such as anthraquinone and pyrenequinone, (6) squarylium dyes, (7) pyrylium salts and thiapyrylium salts, ( 8) Triphenylmethane dyes, (9) inorganic substances such as selenium, selenium-tellurium and amorphous silicon, (10) quinacridone pigments, (11) azulenium salt pigments, (12) cyanine dyes, (13) xanthene dyes, 14) Quinone imine dye, (15) Su Lil dyes, and (16) cadmium sulfide and (17) zinc oxide.

  Examples of the binder resin used for the charge generation layer include polycarbonate resin, polyester resin, polyarylate resin, butyral resin, polystyrene resin, polyvinyl acetal resin, diallyl phthalate resin, acrylic resin, methacrylic resin, vinyl acetate resin, phenol resin, Examples thereof include, but are not limited to, silicone resins, polysulfone resins, styrene-butadiene copolymer resins, alkyd resins, epoxy resins, urea resins, and vinyl chloride-vinyl acetate copolymer resins. These can be used alone or as a mixture or as a copolymer polymer.

  The solvent used for the charge generation layer coating is selected from the solubility and dispersion stability of the resin used and the charge generation material, but examples of the organic solvent include alcohols, sulfoxides, ketones, ethers, esters, Aliphatic halogenated hydrocarbons or aromatic compounds can be used.

  The charge generation layer is well dispersed by a method such as a homogenizer, ultrasonic wave, ball mill, sand mill, attritor or roll mill together with the above-mentioned charge generation material 0.3 to 4 times the amount of binder resin and solvent. It is formed by coating and drying. The thickness is preferably 5 μm or less, and particularly preferably in the range of 0.01 to 1 μm.

  In addition, various sensitizers, antioxidants, ultraviolet absorbers, plasticizers, and known charge generating substances can be added to the charge generation layer as necessary.

The charge transport materials used include various triarylamine compounds, various hydrazone compounds, various styryl compounds, various stilbene compounds, various pyrazoline compounds, various oxazole compounds, various thiazole compounds, and various triarylmethane compounds. Compounds and the like.

  Examples of the binder resin used for forming the charge transport layer include acrylic resin, styrene resin, polyester, polycarbonate resin, polyarylate, polysulfone, polyphenylene oxide, epoxy resin, polyurethane resin, alkyd resin, and unsaturated resin. The resin chosen is preferred. Particularly preferred resins include polymethyl methacrylate, polystyrene, styrene-acrylonitrile copolymer, polycarbonate resin and diallyl phthalate resin.

  The charge transport layer is generally formed by dissolving the above charge transport material and binder resin in a solvent and applying them. The mixing ratio (mass ratio) of the charge transport material and the binder resin is about 2: 1 to 1: 2. Solvents include ketones such as acetone and methyl ethyl ketone, esters such as methyl acetate and ethyl acetate, aromatic hydrocarbons such as toluene and xylene, chlorinated hydrocarbons such as chlorobenzene, chloroform and carbon tetrachloride, tetrahydrofuran, Ethers such as dioxane are used. When this solution is applied, for example, a coating method such as a dip coating method, a spray coating method and a spinner coating method can be used, and drying is preferably 10 ° C to 200 ° C, more preferably 20 ° C to 150 ° C. The temperature is in the range of 5 minutes to 5 hours, and more preferably 10 minutes to 2 hours.

  The charge transport layer is electrically connected to the above-described charge generation layer, receives charge carriers injected from the charge generation layer in the presence of an electric field, and transports these charge carriers to the interface with the protective layer. It has a function. Since this charge transport layer has a limit to transport charge carriers, the film thickness cannot be increased more than necessary, but it is preferably 5 to 40 μm, and particularly preferably 7 to 30 μm.

  Furthermore, an antioxidant, an ultraviolet absorber, a plasticizer, and a known charge transport material can be added to the charge transport layer as necessary.

Furthermore, in the present invention, the protective layer is applied and cured on the charge transport layer to form a film, and a hardness test is performed using a Vickers square pyramid diamond indenter in an environment having a surface of 25 ° C. and a humidity of 50%. And a photoconductor having a HU (Universal Hardness Value) of 150 N / mm ² or more and 240 N / mm ² or less when pressed with a maximum load of 6 mN and an elastic deformation rate of 44% or more and 65% or less is completed. .

  As a protective layer for an electrophotographic photoreceptor satisfying the above conditions, a compound obtained by polymerizing a hole transporting compound having two or more chain polymerizable functional groups in the same molecule as represented by the following general formula (1) There is a protective layer to do.

In the formula, A represents a hole transporting group. P ¹ and ^{P 2} represents a chain polymerizable functional group. P ¹ and P ² may be the same or different. Z represents an organic residue which may have a substituent. a, b, and d represent 0 or an integer of 1 or more, and a + b × d represents an integer of 2 or more. When a is 2 or more, P ¹ may be the same or different. When d is 2 or more, P ² may be the same or different. When b is 2 or more, Z and P ² are the same or different. May be.

  By polymerizing a hole transporting compound having two or more chain polymerizable functional groups in the same molecule, the compound having a hole transporting ability in the protective layer has at least two cross-linking points. It is incorporated into the dimensional cross-linked structure via a covalent bond. The hole transporting compound can be either polymerized alone or mixed with a compound having another chain polymerizable group, and the kind / ratio thereof is arbitrary. As used herein, the compound having another chain polymerizable group includes any monomer or oligomer / polymer having a chain polymerizable group. When the functional group of the hole transporting compound and the functional group of the other chain polymerizable compound are the same group or a group that can be polymerized with each other, they both take a copolymerized three-dimensional crosslinked structure via a covalent bond. Is possible. When both functional groups are functional groups that do not polymerize with each other, the photosensitive layer is a mixture of at least two or more three-dimensional cured products or other chain-polymerizable compound monomers in the three-dimensional cured product as a main component. Although it is comprised as the thing containing the hardened | cured material, it is also possible to form an IPN (Inter Penetrating Network), ie, an interpenetrating network structure, by controlling the compounding ratio / film forming method well.

  In the present invention, the protective layer contains at least one selected from the group consisting of fluorine atom-containing resin, carbon fluoride, and polyolefin resin as a lubricant, and preferred compounds include the following. However, it is not limited to these compounds.

  Preferred as the fluorine atom-containing resin is a polymer or copolymer resin of a compound selected from vinyl fluoride, vinylidene fluoride, chlorotrifluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoropropylene, perfluoroalkyl vinyl ether, and Examples include resin fine particles.

Examples of the carbon fluoride include compounds represented by (CF) _n and (C ₂ F) _n .

Preferred examples of the polyolefin resin include homopolymer resins such as polyethylene resin, polypropylene resin and polybutene resin, copolymer resins such as ethylene-propylene copolymer and ethylene-butene copolymer, and resin powder.
These lubricants can be used alone or in combination of two or more at any ratio.

  Further, the protective layer may contain the above-mentioned lubricant dispersant, dispersion aid, other various additives, surfactants and the like.

  By containing at least one of fluorine atom-containing resin, carbon fluoride, and polyolefin resin as a lubricant in the protective layer, the surface slipperiness and water repellency of the photoreceptor can be improved, and charging during repeated use, Deterioration of transfer efficiency and slipperiness due to chemical deterioration of the surface layer due to development, transfer, etc., and further deterioration of electrical properties such as sensitivity reduction and potential reduction are prevented. Filming, fusing, and cleaning failure even during repeated use It is possible to suppress the occurrence of image defects such as image blur / flow. Particularly preferable results are obtained when the fluorine-containing resin is used.

  In the present invention, the ratio of the lubricant contained in the protective layer is preferably 1 to 50%, more preferably 5 to 40%, based on the total weight of the layer to be the surface layer. When the amount of the lubricant is more than 50%, the mechanical strength of the layer serving as the surface layer tends to be lowered, and when it is less than 1%, the water repellency and slipperiness of the layer serving as the surface layer may not be sufficient.

  In the present invention, a charge transport material can be contained in the protective layer containing the cured product of the hole transport compound having the chain polymerizable group.

  The method for forming the protective layer is generally a polymerization reaction after coating the solution containing the hole transporting compound, but a cured product obtained by reacting the solution containing the hole transporting compound in advance. After obtaining the above, it is possible to form a protective layer by dispersing or dissolving in the solvent again. As a method for applying these solutions, for example, a dip coating method, a spray coating method, a curtain coating method, a spin coating method, and the like are known, but the dip coating method is preferable from the viewpoint of efficiency / productivity.

  In the present invention, the hole transporting compound having a chain polymerizable group is preferably polymerized by radiation. The greatest advantage of polymerization by radiation is that a polymerization initiator is not required, which makes it possible to produce a very high-purity three-dimensional photosensitive layer and to ensure good electrophotographic characteristics. In addition, because it is a short and efficient polymerization reaction, it is highly productive, and because of its good radiation transparency, it inhibits curing when a thick film or additives such as additives are present in the film. The influence of the is very small. However, depending on the type of the chain polymerizable group and the type of the central skeleton, the polymerization reaction may hardly proceed, and in this case, it is possible to add a polymerization initiator within a range that does not affect the polymerization reaction. The radiation used at this time is an electron beam and a gamma ray. In the case of electron beam irradiation, any type such as a scanning type, an electro curtain type, a broad beam type, a pulse type, and a laminar type can be used as an accelerator. When irradiating with an electron beam, the irradiation conditions are very important in the photoreceptor of the present invention in order to develop electric characteristics and durability. In the present invention, the acceleration voltage is preferably 250 kV or less, and optimally 150 kV or less. The dose is preferably in the range of 10 kGy to 1000 kGy, more preferably in the range of 30 kGy to 500 kGy. When the accelerating voltage exceeds the above, the electron beam irradiation damage to the characteristics of the photoreceptor tends to increase. Further, when the dose is less than the above range, the curing tends to be insufficient, and when the dose is large, the photoreceptor characteristics are likely to deteriorate.

A photoreceptor having a surface layer containing a hole transport compound obtained by polymerizing a compound having an unsaturated functional group in the molecule, produced as described above, has a universal hardness value (hereinafter HU) of 150 to 240 ( N / mm ² ) and an elastic deformation rate of 44% or more and 65% or less, and as shown in JP-A-2001-166509, an electrophotographic photoreceptor using a conventional resin as a surface layer has The above problems have been solved, the film strength is increased to improve the wear resistance and scratch resistance, and the precipitation resistance is good. Electrophotographic photoconductor with very little change and deterioration, stable performance even when used repeatedly, improved wear resistance and scratch resistance of the surface layer of the electrophotographic photoconductor, and long life and high image quality It is.

The measurement method used in the present invention will be described below.

<Measurement of resistivity of magnetic carrier>
The specific resistance of the magnetic carrier used in the present invention is measured using a measuring apparatus schematically shown in FIG. A resistance measurement cell E is filled with a magnetic carrier 47, a lower electrode 41 and an upper electrode 42 are arranged so as to be in contact with the filled magnetic carrier, a voltage is applied between these electrodes, and a current flowing at that time is measured. Thus, the specific resistance of the magnetic carrier is obtained.
The specific resistance is measured under the condition that the contact area S between the filled magnetic carrier and the electrode is about 2.3 cm ² , the sample thickness L of the filled magnetic carrier is about 0.8 mm, and the load of the upper electrode 42 is 180 g. .
In addition, the specific resistance of a nonmagnetic inorganic compound, a magnetic material, and conductive particles can be measured in the same manner.

<Method for measuring weight average particle diameter of toner>
The weight average particle diameter of the toner used in the replenishment developer of the present invention can be measured using a Coulter Counter TA-II or Coulter Multisizer II (manufactured by Beckman Coulter, Inc.) as a measuring device. The electrolytic solution is an approximately 1% NaCl aqueous solution, may be prepared using primary sodium chloride, or may be a commercially available product of ISOTON (registered trademark) -II (manufactured by Coulter Scientific Japan).
The weight average particle diameter of the toner is measured as follows. To 100 to 150 ml of the electrolytic solution, 0.1 to 5 ml of a surfactant (preferably alkylbenzenesulfone hydrochloride) is added as a dispersant, and 2 to 20 mg of a measurement sample (toner) is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes to obtain a measurement sample.
The aperture is a 100 μm aperture. The volume and number of samples are measured for each channel, and the volume distribution and number distribution of the samples are calculated. From the calculated distribution, the weight average particle diameter of the sample is obtained. As channels, 2.00 to 2.52 μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm; 4.00 to 5.04 μm; 5.04 to 6.35 μm; 6.35 to 8. 00μm; 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32.00 μm; 13 channels of 32-40.30 μm are used.

<Measuring method of number average particle diameter (D1) of inorganic fine particles>
The number average particle size of the inorganic fine particles is binarized by taking a photograph of the surface of the toner particles magnified 100,000 times with a scanning electron microscope FE-SEM (S-4700, manufactured by Hitachi, Ltd.), adjusting the contrast of the image. To do. Further, the binarized image is further enlarged, and for each particle, for example, the major axis of the particle is measured for 50 particles using a ruler, caliper, etc., and the number average particle diameter is measured. At that time, the composition determination of the fine particles is performed by detecting only the specified specific element with the X-ray microanalyzer of the apparatus.

<Measurement of molecular weight of resin by GPC>
The molecular weight of the chromatogram by gel permeation chromatography (GPC) can be measured under the following conditions.

Resin adjusted to 0.05 to 0.6% by mass as a sample concentration by stabilizing the column in a heat chamber at 40 ° C., and flowing tetrahydrofuran (THF) as a solvent at a flow rate of 1 ml / min. Measurement is performed by injecting 50 to 200 μl of a THF sample solution. An RI (refractive index) detector is used as the detector. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns in order to accurately measure a molecular weight region of 10 ^{3 to} 2 × 10 ⁶ . As a combination of such commercially available polystyrene gel columns, for example, a combination of μ-styrene 500, 103, 104, 105 manufactured by Waters, or shodex KA-801, 802, 803, 804, 805 manufactured by Showa Denko KK , 806, and 807 are preferable.

In measuring the molecular weight of the resin, which is a sample, the molecular weight distribution of the resin is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Manufactured by Toyo Soda Kogyo Co., Ltd., with molecular weights of 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ are used. It is appropriate to use at least about 10 standard polystyrene samples.

<Measurement of BET specific surface area>
The BET specific surface area can be calculated using a BET multipoint method by adsorbing nitrogen gas to the sample surface according to the BET method using a specific surface area measuring device Autosorb 1 (manufactured by Yuasa Ionics).

  Hereinafter, the present invention will be described more specifically with reference to specific production examples and examples. However, the present invention is not limited to these examples.

<Resin A production example (hybrid resin)>
As a vinyl polymer, 1.9 mol of styrene, 0.21 mol of 2-ethylhexyl acrylate, 0.15 mol of fumaric acid, 0.03 mol of α-methylstyrene dimer, and 0.05 mol of dicumyl peroxide were placed in a dropping funnel. . In addition, 7.0 mol of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane; 0 mol, 3.0 mol of terephthalic acid, 2.0 mol of trimellitic anhydride, 5.0 mol of fumaric acid and 0.2 g of dibutyltin oxide are placed in a 4-liter four-necked flask made of glass, a thermometer, a stirring rod, a condenser and nitrogen The introduction tube was installed and placed in a mantle heater. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually increased while stirring, and while stirring at a temperature of 145 ° C., the monomer of the vinyl resin, the crosslinking agent and the polymerization initiator were added from the previous dropping funnel. It was dripped over 5 hours. Subsequently, the temperature was raised to 220 ° C. and reacted for 4 hours to obtain a hybrid resin (resin A). Table 1 shows the results of molecular weight measurement by GPC (gel permeation chromatography). In Table 1, Mw is a weight average molecular weight, Mn is a number average molecular weight, and Mp is a peak molecular weight.

<Resin B production example (styrene acrylic resin production example)>
-70 parts by mass of styrene-25 parts by mass of n-butyl acrylate-5 parts by mass of monobutyl maleate-1 part by mass of di-t-butyl peroxide 1 200 parts by mass of xylene in a four-necked flask were stirred. Then, the inside of the container was sufficiently replaced with nitrogen, and the temperature was raised to 120 ° C., followed by dropwise addition over 3.0 hours. Further, the polymerization was completed after refluxing xylene, and the solvent was distilled off under reduced pressure to obtain a styrene-acrylic resin (resin B). Table 1 shows the results of molecular weight measurement by GPC (gel permeation chromatography).

<Resin C production example (polyester resin production example)>
3.6 mol of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 1.6 mol of polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 1.7 mol of terephthalic acid, 1.1 mol of trimellitic anhydride, 2.4 mol of fumaric acid and 0.1 g of dibutyltin oxide are placed in a 4-liter 4-neck flask made of glass, a thermometer, a stir bar, a condenser and a nitrogen inlet tube Was installed in a mantle heater. Under a nitrogen atmosphere, the mixture was reacted at 200 ° C. for 6 hours to obtain a polyester resin (resin C). The results of molecular weight measurement by GPC (gel permeation chromatography) were performed in the same manner as in the hybrid resin production example, and the results are shown in Table 1.

<Toner Production Example 1>
・ Hybrid resin (resin A) 100 parts by mass I. Pigment Blue 15: 3 5 parts by mass, normal paraffin wax (maximum endothermic peak measured by differential scanning calorimeter (DSC): 70 ° C.) 5 parts by mass, aluminum compound of di-tert-butylsalicylic acid (charge control agent) 3 parts by mass The above materials were sufficiently premixed with a Henschel mixer and melt kneaded at an arbitrary barrel temperature with a twin-screw extrusion kneader. After cooling, it was coarsely pulverized to about 1 to 2 mm using a hammer mill, and then finely pulverized to a particle size of 12 μm or less with an air jet fine pulverizer. Furthermore, the pulverized product was classified by a multi-division classifier using the Coanda effect, and cyan resin particles (classified products) were obtained as colored particles having a volume average particle size of 5.5 μm in the particle size distribution. To 100 parts by mass of the obtained cyan resin particles (classified product), 1.0 part by mass of hydrophobic silica (BET: 200 m ² / g) and titanium oxide fine particles surface-treated with isobutyltrimethoxysilane (BET: 80 m ² / g) Toner 1 was obtained by adding 1.0 part by weight of g) and mixing with a Henschel mixer.

<Toner Production Example 2>
In Toner Production Example 1, C.I. I. Pigment Blue 15: 3 to C.I. I. Toner 2 was obtained in the same manner as in Toner Production Example 1 except that CI Pigment Yellow 74 was used.

<Toner Production Example 3>
In Toner Production Example 1, C.I. I. Pigment Blue 15: 3 to C.I. I. Toner 3 was obtained in the same manner as in Toner Production Example 1 except that CI Pigment Red 122 was used.

<Toner Production Example 4>
In Toner Production Example 1, C.I. I. Toner 4 was obtained in the same manner as in Toner Production Example 1, except that CI Pigment Blue 15: 3 was changed to carbon black.

<Toner Production Example 5>
Toner 5 was obtained in the same manner as in Toner Production Example 1 except that Resin B was used instead of Resin A in Toner Production Example 1.

<Toner Production Example 6>
Toner 6 was obtained in the same manner as in Toner Production Example 1 except that Resin C was used instead of Resin A in Toner Production Example 1.

<Toner Production Example 7>
In a 2 liter four-necked flask equipped with a high-speed stirring device TK-homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), 710 parts by mass of ion-exchanged water and 450 parts by mass of a 0.1 mol / liter-Na ₃ PO ₄ aqueous solution were added. The number of revolutions of the high-speed stirring device was adjusted to 10,000 m / s, and the mixture was heated to 60 ° C. To this, 68 parts by mass of a 1.0 mol / liter-CaCl ₂ aqueous solution was gradually added to prepare an aqueous dispersion medium containing minute hardly water-soluble dispersed Ca ₃ (PO ₄ ) ₂ .
on the other hand,
-Styrene monomer 165 mass parts-N-butyl acrylate monomer 35 mass parts-Divinylbenzene monomer 0.5 mass part-C.I. I. Pigment Blue 15: 3 14 parts by mass, Resin B 10 parts by mass, aluminum compound of di-tert-butylsalicylic acid (charge control agent) 2 parts by mass, ester wax (maximum endotherm measured with a differential scanning calorimeter (DSC) (Peak: 68 ° C.) 20 parts by mass After the above raw materials were dispersed for 3 hours using an attritor (manufactured by Mitsui Kinzoku Co., Ltd.), 10 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator The polymerizable monomer composition obtained by adding the part was put into the aqueous dispersion medium, and granulation was carried out while maintaining the rotational speed of the high-speed stirrer at 10,000 m / s. Thereafter, the mixture was reacted at 70 ° C. for 2 hours while stirring with a paddle stirring blade, and then polymerized at 90 ° C. for 10 hours.
After completion of the reaction, the suspension was cooled, diluted hydrochloric acid was added to dissolve the poorly water-soluble dispersant, filtered, washed with water, dried, and then classified by air classification to obtain colored particles. Similarly to Toner Production Example 1 Hydrophobic silica ^(BET: 200m 2 /g)1.0 parts by mass of titanium oxide fine particles surface-treated with isobutyl trimethoxysilane (BET: ^80m 2 / g) 1.0 mass outsiders Addition and mixing were performed to obtain toner 7.

<Toner Production Example 8>
-Preparation of resin particle dispersion 1 Styrene 370 gn-butyl acrylate 30 g Acrylic acid 6 g Dodecanethiol 24 g Carbon tetrabromide 4 g
While mixing and dissolving the above, 6 g of nonionic surfactant and 10 g of anionic surfactant dissolved in 550 g of ion-exchanged water are dispersed in a flask, emulsified, and slowly mixed for 10 minutes. Into this, 50 g of ion-exchanged water in which 4 g of ammonium persulfate was dissolved was added, and after nitrogen substitution, the contents in the flask were heated in an oil bath until the temperature reached 70 ° C. while stirring, and the emulsion polymerization was continued for 5 hours. Continued. Thus, a resin particle dispersion 1 was prepared by dispersing resin particles having a number average particle size of 150 nm, a glass transition point (Tg) of 62 ° C., and a weight average molecular weight (Mw) of 12,000.
Preparation of resin particle dispersion 2 Styrene 280 gn-butyl acrylate 120 g Acrylic acid 8 g
6 g of nonionic surfactant and anionic surfactant 1 were prepared by mixing and dissolving the above.
Disperse 2 g in ion-exchanged water 550 g in a flask, emulsify, and slowly mix for 10 minutes. Thereafter, the contents in the flask were stirred and heated in an oil bath until the content reached 70 ° C., and emulsion polymerization was continued as it was for 5 hours. The number average particle size was 110 nm, the glass transition point (Tg) was 55 ° C., and weight. A resin particle dispersion 2 was prepared by dispersing resin particles having an average molecular weight (Mw) of 550,000.
Preparation of release agent particle dispersion 1 Polypropylene wax (maximum endothermic peak measured with a differential scanning calorimeter (DSC): 85 ° C.) 50 g
Anionic surfactant 5g Ion exchange water 200g
The above is heated to 95 ° C., dispersed using a homogenizer, etc., and then dispersed with a pressure discharge type homogenizer, and a release agent particle dispersion liquid 1 in which a release agent having a number average particle size of 570 nm is dispersed. Was prepared.
-Preparation of colorant particle dispersion 1 I. Pigment Blue 15: 3 20 g Anionic surfactant 2 g Ion-exchanged water 78 g
The above was mixed and dispersed for 10 minutes at an oscillation frequency of 26 kHz using an ultrasonic cleaner to prepare a colorant particle dispersion (anionic) 1.
Preparation of liquid mixture Resin particle dispersion 1 180 g Resin particle dispersion 2 80 g Colorant particle dispersion 1 30 g Release agent particle dispersion 1 50 g
The above was mixed in a round stainless steel flask using a homogenizer or the like and dispersed to prepare a mixed solution.
-Formation of Aggregated Particles 1.5 g of a cationic surfactant as an aggregating agent was added to the above mixed solution, and the mixture was heated to 50 ° C. while stirring the inside of the flask in a heating oil bath. After maintaining at 50 ° C. for 1 hour, it was confirmed by observation with an optical microscope that aggregated particles having a volume average particle diameter of about 6.1 μm were formed.
-Fusion Then, 3 g of an anionic surfactant was added thereto, and then the stainless steel flask was sealed, heated to 105 ° C while continuing to stir using a magnetic seal, and held for 3 hours. After cooling, the reaction product is filtered and thoroughly washed with ion-exchanged water, and then, as in dry toner production example 1, 1.0 part by weight of hydrophobic silica (BET: 200 m ² / g), isobutyltrimethoxy Toner 8 was obtained by externally adding 1.0 part by mass of titanium oxide fine particles (BET: 80 m ² / g) surface-treated with silane.

<Toner Production Example 9>
In Toner Production Example 5, 100 parts by mass of the obtained cyan resin particles (classified product), 1.0 part by mass of hydrophobic silica (BET: 200 m ² / g), titanium oxide fine particles surface-treated with isobutyltrimethoxysilane Toner 9 was obtained in the same manner as in Toner Production Example 5, except that 1.0 part by mass of (BET: 80 m ² / g) and 1.0 part by mass of inorganic fine particles 8 in Table 3 were added.

<Production example 1 of inorganic fine particles>
A slurry of hydrous titanium oxide obtained by hydrolyzing a titanyl sulfate aqueous solution was washed with an alkaline aqueous solution. Next, hydrochloric acid was added to the hydrous titanium oxide slurry to adjust the pH to 4.0 to obtain a titania sol dispersion. NaOH was added to the titania sol dispersion, the pH of the dispersion was adjusted to 8.0, and washing was repeated until the electrical conductivity of the supernatant reached 100 μS / cm. To this hydrous titanium oxide, 1.02 times the molar amount of Sr (OH) ₂ .8H ₂ O was added and placed in a SUS reaction vessel, and the nitrogen gas was replaced. Furthermore, distilled water was added so as to be 0.3 mol / liter in terms of SrTiO ₃ . The slurry was heated to 90 ° C. at 30 ° C./hour in a nitrogen atmosphere, and reacted for 5 hours after reaching 90 ° C. After the reaction, the reaction solution was cooled to room temperature, and the supernatant was removed. Then, the washing was repeated with pure water, and then filtered with Nutsche. The obtained cake was dried to obtain strontium titanate fine particles having a number average particle diameter (D1) of 52 nm. The strontium titanate fine particles were designated as inorganic fine particles 1. The particle size of the inorganic fine particles is summarized in Table 2.

<Production example 2 of inorganic fine particles>
The hydrous titanium oxide slurry obtained by hydrolyzing the aqueous titanyl sulfate solution was washed with an alkaline aqueous solution. Next, hydrochloric acid was added to the hydrous titanium oxide slurry to adjust the pH to 0.65 to obtain a titania sol dispersion. NaOH was added to the titania sol dispersion, the pH of the dispersion was adjusted to 4.5, and washing was repeated until the electrical conductivity of the supernatant reached 70 μS / cm. 0.97-fold molar amount of Sr (OH) ₂ .8H ₂ O was added to the hydrous titanium oxide, and the mixture was placed in a SUS reaction vessel and purged with nitrogen gas. Further, distilled water was added so as to be 0.5 mol / liter in terms of SrTiO ₃ . The slurry was heated to 83 ° C. at 6.5 ° C./hour in a nitrogen atmosphere, and reacted for 6 hours after reaching 83 ° C. After the reaction, the reaction solution is cooled to room temperature, the supernatant is removed, and washing is repeated with pure water.
Furthermore, in a nitrogen atmosphere, the slurry is placed in an aqueous solution in which 6.5% by mass of sodium stearate is dissolved with respect to the solid content of the slurry, and while stirring, an aqueous zinc sulfate solution is added dropwise to the surface of the perovskite crystal. Zinc acid was precipitated.
The slurry was washed repeatedly with pure water and then filtered with Nutsche, and the resulting cake was dried to obtain strontium titanate surface-treated with zinc stearate.
The obtained strontium titanate had a substantially cubic or rectangular particle shape and a number average particle diameter (D1) of 105 nm. This strontium titanate is used as the inorganic fine particles 2. In the present invention, the particle diameter of the inorganic fine particles is defined as the major diameter of the binarized image of the inorganic fine particles in the measurement method described above.

<Production Example 3 of Inorganic Fine Particle>
The hydrous titanium oxide obtained by hydrolysis by adding ammonia water to the aqueous titanium tetrachloride solution was washed with pure water until the electrical conductivity of the supernatant reached 90 μS / cm. A 1.6-fold molar amount of Sr (OH) ₂ .8H ₂ O was added to the hydrous titanium oxide, and the mixture was placed in a SUS reaction vessel and purged with nitrogen gas. Further, distilled water was added so as to be 0.2 mol / liter in terms of SrTiO ₃ . The slurry was heated to 78 ° C. at 12 ° C./hour in a nitrogen atmosphere, and reacted for 3.5 hours after reaching 78 ° C. After the reaction, the mixture was cooled to room temperature, the supernatant was removed, washed repeatedly with pure water, filtered through Nutsche, and the resulting cake was dried to obtain strontium titanate. The obtained strontium titanate had a substantially cubic or cuboid particle shape and a number average particle diameter (D1) of 293 nm. This strontium titanate is used as inorganic fine particles 3.

<Production Example 4 of Inorganic Fine Particle>
The hydrous titanium oxide obtained by hydrolysis by adding ammonia water to the aqueous titanium tetrachloride solution was washed with pure water until the electrical conductivity of the supernatant reached 90 μS / cm. A 1.5-fold molar amount of Sr (OH) ₂ .8H ₂ O was added to the hydrous titanium oxide, placed in a SUS reaction vessel, and purged with nitrogen gas. Further, distilled water was added so as to be 0.2 mol / liter in terms of SrTiO ₃ . The slurry was heated to 80 ° C. at 15 ° C./hour in a nitrogen atmosphere, and reacted for 4.5 hours after reaching 80 ° C. After the reaction, the reaction solution is cooled to room temperature, the supernatant is removed, and washing is repeated with pure water. Further, in a nitrogen atmosphere, the slurry is placed in an aqueous solution in which 18% by mass of sodium stearate is dissolved with respect to the solid content of the slurry, and while stirring, an aqueous zinc sulfate solution is dropped, and zinc stearate is deposited on the perovskite crystal surface. Was precipitated. The slurry was washed repeatedly with pure water and then filtered with Nutsche, and the resulting cake was dried to obtain strontium titanate surface-treated with zinc stearate.
The obtained strontium titanate had an approximate cubic or rectangular particle shape and a number average particle diameter (D1) of 320 nm. This strontium titanate is used as the inorganic fine particles 4.

<Inorganic fine particle production example 5>
The hydrous titanium oxide obtained by hydrolysis by adding aqueous ammonia to the aqueous titanium tetrachloride was washed with pure water, and 0.3% sulfuric acid was added to the hydrous titanium oxide slurry as SO _{3 with} respect to the hydrous titanium oxide. Added. Next, hydrochloric acid was added to the hydrous titanium oxide slurry to adjust the pH to 0.6 to obtain a titania sol dispersion. NaOH was added to the titania sol dispersion, the pH of the dispersion was adjusted to 5.0, and washing was repeated until the electrical conductivity of the supernatant liquid reached 50 μS / cm. 0.97-fold molar amount of Sr (OH) ₂ .8H ₂ O was added to the hydrous titanium oxide, and the mixture was placed in a SUS reaction vessel and purged with nitrogen gas. Furthermore, distilled water was added so as to be 0.6 mol / liter in terms of SrTiO ₃ . The slurry was heated to 60 ° C. at 10 ° C./hour in a nitrogen atmosphere, and reacted for 9 hours after reaching 60 ° C. After the reaction, the reaction solution was cooled to room temperature, and the supernatant was removed. Then, the washing was repeated with pure water, and then filtered with Nutsche. The obtained cake was dried to obtain strontium titanate fine particles not passing through the sintering step. The obtained strontium titanate had a number average particle diameter (D1) of 46 nm. This strontium titanate is used as the inorganic fine particles 5.

<Production Example 6 of Inorganic Fine Particle>
Sodium hydroxide was added to a solution in which solid titanium oxide was dissolved in dilute sulfuric acid, and after sufficient stirring, decantation was performed to obtain an aqueous solution containing a titanium hydrate sol. After adding calcium acetate aqueous solution to this sol-containing aqueous solution and stirring and mixing, pH is adjusted with aqueous sodium hydroxide solution.
It was adjusted. Next, each mixed solution was allowed to stand for 6 hours at a liquid temperature of 5 ° C. without stirring or shaking. After standing, decantation was performed to remove chlorine ions, sodium ions, etc., and the precipitate was filtered and dried to obtain a dried product. The dried product was heat-treated at 700 ° C. for 3 hours to obtain perovskite-type calcium titanate having a number average particle diameter (D1) of 120 nm. This calcium titanate is used as inorganic fine particles 6.

<Inorganic fine particle production example 7>
An aqueous NaOH solution having a concentration of 0.92 N was kept at about 90 ° C. and heated to 40 ° C., and an aqueous TiCl ₄ solution (TiCl ₄ concentration 0.472 mol / l) was previously removed from the undissolved portion at about 95 ° C.
BaCl ₂ / NaOH aqueous solution (BaCl ₂ concentration 0.258 mol / liter, NaOH concentration 2.73 mol / liter) was continuously supplied into the reaction vessel. The temperature of the mixed aqueous solution was kept constant at about 90 ° C. and stirred for 2 minutes to form particulate barium titanate. After aging, decantation was performed to separate and wash the supernatant and the precipitate, and the solid reaction product was recovered. The recovered solid reactant was dried by heating at 100 ° C. in an air atmosphere. Furthermore, it heated at 900 degreeC for 30 minutes, and obtained the barium titanate powder whose number average particle diameter (D1) is 220 nm. This barium titanate is used as inorganic fine particles 7.

<Production Example 8 of Inorganic Fine Particle>
The slurry of Mg (OH) ₂ powder and SiO ₂ powder are weighed so as to be 2: 1 with MgO: SiO ₂ (molar ratio), and 150 L with a MgO concentration of 71.5 g / liter and a SiO ₂ concentration of 53.3 g / liter. Then, wet pulverization was performed in a sand grinder mill. The slurry was spray-dried with a spray dryer and fired at 1100 ° C. for 30 minutes in the air in an electric furnace. Thereafter, the fired product was slurried and wet pulverized with a sand grinder mill. The slurry was spray-dried with a spray dryer and pulverized with a sand mill. The number average particle diameter (D1) of the primary particles of magnesium silicate obtained as described above was 110 nm. This magnesium silicate is referred to as inorganic fine particles 8.

<Production Example 9 of inorganic fine particles>
After adding 148.7 ml of a 1.6 mol / liter aqueous cerium chloride (CeCl ₃ ) solution and 19.7 g of 31 wt% hydrogen peroxide solution in terms of CeO ₂ , pure water was added to make the total amount 200 ml. Hereinafter, this is referred to as raw material A. On the other hand, a 28 wt% aqueous ammonia, the atomic ratio of Cl contained in the NH ₃ and CeCl _{3 (NH} 3 / Cl) are weighed 65.6ml to be 1.5, this was added pure water total amount Was 200 ml. Hereinafter, this is referred to as raw material B. Next, all of the raw material A and the raw material B were put in a beaker and dropped while stirring to precipitate cerium oxide-containing cerium gel. At this time, 50 ml of pure water was previously added to the beaker. Next, this precipitated gel was heat-treated at 150 ° C. for 24 hours in an autoclave to obtain 500 ml of slurry, which was filtered and washed with pure water five times, further washed with 200 ml of ethyl alcohol, stirred, filtered and dried under reduced pressure. As a result, a powder having a number average particle diameter (D1) of 105 nm was obtained. This cerium oxide is used as inorganic fine particles 9.

<Manufacture example 10 of inorganic fine particles>
Using slaked lime powder obtained by dry slaked quick lime with a theoretical water ratio of 1.5, lime milk with a concentration of 450 g / liter is prepared and treated with a high-speed impeller disperser, and then the lime milk has a concentration of 120 g / liter. Adjusted. While stirring, a carbonation reaction was carried out by blowing CO ₂ -containing gas having a CO ₂ concentration of 29 vol% into lime milk. In the carbonation reaction, a CO ₂ -containing gas is blown until the carbonation rate becomes 6.2% at a feed rate of 18 m ³ / m ² · hr as the first stage, and then the feed rate is set to 1.5 m ³ / Reduce to m ² · hr and blow in CO ₂ -containing gas until the carbonation rate reaches 12.8%. Further, as the third stage, increase the feed rate to 18 m ³ / m ² · hr and increase the carbonation rate to 44.5%. The CO ₂ -containing gas was blown until the reaction was performed. When the obtained reaction product was observed with a scanning electron microscope, it was in the form of a hexagonal plate having an average major axis of 2 μm and a thickness of 0.2 μm. Further, when a TG curve in the thermogravimetric analysis of this product was obtained, a composition formula of CaCO ₃ · 1.6Ca (OH) ₂ · H ₂ O was obtained.
1 mol of calcium hydroxide aqueous suspension having a viscosity of 2500 cp at 25 ° C. and a concentration of 400 g / l was mixed with 1 mol of the obtained calcium carbonate hexagonal plate composite. Carbon dioxide containing gas with a carbon dioxide concentration of 30% by volume at a reaction start temperature of 25 ° C. was blown into the resulting mixture at a supply rate of 8.0 m ³ / m ² · hr, and the carbonation rate was 50.5%. The aqueous hexagonal plate composite was averaged and coarsened to a thickness of 0.4 μm with a major axis of 3.8 μm to prepare an aqueous suspension A. On the other hand, an aqueous calcium hydroxide suspension having a viscosity of 2500 cp at 25 ° C. and a concentration of 400 g / l was prepared to a concentration of 50 g / l, and a carbon dioxide-containing gas having a carbon dioxide concentration of 30 vol% at a reaction start temperature of 13 ° C. An aqueous suspension B was prepared by blowing at a feeding rate of 10.0 m ³ / m ² · hr until the carbonation rate was 32.3%. Next, liquid A and liquid B were mixed so that the molar ratio of Ca-based compound in liquid A and Ca-based compound in liquid B was 100: 8, and the carbon dioxide concentration was 30% by volume at a reaction start temperature of 15 ° C. The carbon dioxide-containing gas was blown at a supply rate of 15 m ³ / m ² · hr and reacted to obtain uniform cubic calcium carbonate having a number average particle size of 150 nm. This calcium carbonate is used as inorganic fine particles 10.

<Production Example 11 of Inorganic Fine Particle>
A 25% aqueous ammonia solution was added to 600 ml of a 0.5 mol / liter FeCl ₃ aqueous solution. The reaction temperature at this time was 10 ° C., and the pn of the slurry was adjusted with a pH meter, and the slurry was added so that the pH of the slurry was 7.0. The slurry was stirred at 10 ° C. for 1.5 hours, passed through a suction port, and dried at 120 ° C. Thereafter, it was washed to remove ammonium chloride and dried again. Spherical iron oxide particles having a number average particle diameter of 60 nm were obtained. The iron oxide particles are referred to as inorganic fine particles 11.

<Inorganic Fine Particle Production Example 12>
1 liter of a 1.4 mol / liter sodium sulfate aqueous solution was charged into a 5 liter reaction vessel at a temperature of 50 ° C., and 3.3 g of sodium hexametaphosphate was added and dissolved therein. While stirring this mixed solution, 1.75 liter of 0.8 mol / liter barium sulfide aqueous solution was added dropwise thereto and reacted at a temperature of 50 ° C. for 1 hour. After completion of dropping, the mixture was further stirred for 30 minutes. The obtained slurry was filtered and washed with a filter press, and the water-containing cake was dried at a temperature of 100 ° C. for 24 hours and then pulverized to obtain fine barium sulfate having a number average particle diameter of 100 nm. This barium sulfate is used as inorganic fine particles 12.

<Manufacture example 13 of inorganic fine particles>
High-purity magnesium obtained by distillation and purification of magnesium metal is heated and vaporized at 1150 ° C. and introduced into an oxidation reactor. Further, argon gas with a purity of 99.9% is introduced as a dilute agent and a magnesium vapor pressure of 0.04 atm. Then, oxidation was performed at a temperature of 1000 ° C. while introducing oxygen gas having a purity of 99.9%. The generated magnesia fine particles were circulated during oxidation, and melt-grown in an oxidation flame to obtain a magnesium oxide (MgO) powder having a number average particle diameter of 200 nm manufactured by a gas phase oxidation reaction method. The magnesium oxide particles are referred to as inorganic fine particles 13.

<Inorganic fine particle production example 14>
SiCl ₄ was dispersed in an organic solvent and maintained at 25 ° C. NH ₃ was blown into the reaction, and the reaction product was filtered and washed to obtain silicon diimide. The obtained silicon diimide was calcined at 950 ° C. to obtain amorphous silicon nitride powder. This amorphous silicon nitride powder was crystallized by heating at 1350 ° C. in a nitrogen gas stream to obtain an α-type silicon nitride powder, which was further pulverized to obtain a silicon nitride fine powder having a number average particle size of 80 nm. .
This was washed, filtered, dried, and crushed by ordinary methods to obtain silicon nitride fine particles. The silicon nitride fine particles are referred to as inorganic fine particles 14.

<Example of production of magnetic fine particle dispersed resin core>
Magnetite fine particles (specific resistance 5 × 10 ⁷ (Ω · cm)) having a number average particle size of 0.30 μm, (magnetization strength under a magnetic field of 10000 / 4π (kA / m), magnetization strength 75 Am ² / kg)) And 3.5% by mass and 2.0% by mass of a silane coupling agent (having a specific resistance of 3 × 10 ⁸ (Ω · cm)), respectively, 3- (2-aminoethylaminopropyl) trimethoxysilane) was added, and the mixture was stirred at a high speed at 120 ° C. or higher in the container to treat each fine particle.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37% by weight aqueous solution) 6 parts by weight-74 parts by weight of the above treated magnetite fine particles-10 parts by weight of the above treated hematite fine particles The above materials, 5 parts by weight of 28% by weight ammonia water and water 10 mass parts was put into a flask, heated and maintained at 85 ° C. over 45 minutes with stirring and mixing, and the phenol resin produced by polymerization reaction for 3 hours was cured. Thereafter, the cured phenol resin was cooled to 30 ° C., water was further added, the supernatant was removed, the precipitate was washed with water, and then air-dried. Next, this was dried under reduced pressure (5 hPa or less) at a temperature of 60 ° C. to obtain a magnetic fine particle dispersed resin core (A) in which magnetic fine particles were dispersed. The obtained magnetic fine particle dispersed resin core had a number average particle diameter of 35 μm and a BET specific surface area of 0.07 (m ² / g).

<Example of manufacturing magnetic carrier core>
The mixture was weighed so that the molar ratio was Fe ₂ O ₃ = 54 mol%, CuO = 16 mol%, and MgO = 30 mol%, and mixed for 8 hours using a ball mill. This was calcined at 900 ° C. for 2 hours, pulverized with a ball mill, and further granulated with a spray dryer. This was sintered at 1150 ° C. for 10 hours, pulverized and further classified to obtain a magnetic carrier core (B). The obtained magnetic carrier core (B) had a number average particle diameter of 35 μm and a BET specific surface area of 0.15 (m ² / g).

<Magnetic carrier production example 1>
The above-mentioned magnetic fine particle dispersed resin core (A) was put into a coater (Okada Seiko Co., Ltd .: Spira coater), and humidified nitrogen was introduced to adjust the moisture content to 0.3% by mass. Thereafter, 3% by mass of γ-aminopropyltrimethoxysilane diluted with a toluene solvent was applied to the core surface while continuously applying a shear stress. Evaporate the solvent under a dry nitrogen stream and coat a mixture of 0.5% by mass of straight silicone resin whose substituents are all methyl groups and 0.015% by mass of γ-aminopropyltrimethoxysilane using toluene as a solvent. did. This was carried out while volatilizing the solvent under a dry nitrogen stream. Further, this magnetic coat carrier was baked at 140 ° C., and the aggregated coarse particles were cut with a 100 mesh sieve, and then fine particles and coarse particles were removed with a multi-division wind classifier to adjust the particle size distribution. Thereafter, the magnetic carrier 1 was obtained by adjusting the humidity for 100 hours in a hopper maintained at 23 ° C. and 60% RH.

<Magnetic carrier production example 2>
20 parts by mass of toluene, 20 parts by mass of butanol, 20 parts by mass of water, and 40 parts by mass of ice are placed in a four-necked flask and mixed with 15 mols of CH ₃ SiCl _{3 and} 10 mols of (CH ₃ ) ₂ SiCl ₂ while stirring. After stirring for 30 minutes, a condensation reaction was performed at 60 ° C. for 1 hour. Thereafter, the siloxane was thoroughly washed with water and dissolved in a toluene-methyl ethyl ketone-butanol mixed solvent to prepare a silicone varnish having a solid content of 10%.
In this silicone varnish, 2.0 parts by mass of ion-exchanged water and 2.0 parts by mass of the curing agent (3) below and 3.0 parts by mass of the following aminosilane coupling agent with respect to 100 parts by mass of the siloxane solid form. (4) was added simultaneously to prepare a carrier coating solution.

  The above coating solution is applied to 100 parts by mass of the aforementioned magnetic carrier core (B) with a coating machine (Okada Seiko Co., Ltd .: Spiracoater) so that the resin coating amount is 1.0 part by mass as a silicon resin coated carrier. A magnetic carrier 2 was obtained.

<Production Example 1 of Mixture of Inorganic Fine Particles and Magnetic Carrier>
0.200 parts by mass of the inorganic fine particles 1 shown in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1, and in a normal temperature and normal humidity (23 ° C., 50% RH) environment, a V-type mixer (V-20 , Manufactured by Tokuju Kogakusha Co., Ltd.) at 30 m / min for 3 minutes to obtain a mixture 1 of inorganic fine particles and magnetic carrier. Table 3 shows a list of mixtures of magnetic carriers, inorganic fine particles and magnetic carriers, and mixing conditions of the mixtures.

<Production Example 2 of mixture of inorganic fine particles and magnetic carrier>
0.400 parts by mass of the inorganic fine particles 2 shown in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1 and 30 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 3 minutes to obtain a mixture 2 of inorganic fine particles and magnetic carrier.

<Production Example 3 of mixture of inorganic fine particles and magnetic carrier>
1.000 parts by mass of the inorganic fine particles 3 shown in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1, and 30 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 3 minutes to obtain a mixture 3 of inorganic fine particles and magnetic carrier.

<Production Example 4 of mixture of inorganic fine particles and magnetic carrier>
2.5 parts by mass of the inorganic fine particles 4 in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1, and 85 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 3 minutes to obtain a mixture 4 of inorganic fine particles and magnetic carrier.

<Production Example 5 of mixture of inorganic fine particles and magnetic carrier>
To 100.000 parts by mass of the magnetic carrier 1, 2.5 parts by mass of the inorganic fine particles 5 shown in Table 2 was added, and 70 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 3 minutes to obtain a mixture 5 of inorganic fine particles and magnetic carrier.

<Production Example 6 of mixture of inorganic fine particles and magnetic carrier>
0.5 part by mass of inorganic fine particles 6 shown in Table 2 is added to 100.000 parts by mass of the magnetic carrier 1, and 25 m using a V-type mixer in an environment of normal temperature and humidity (23 ° C., 50% RH) / Min for 3 minutes to obtain a mixture 6 of inorganic fine particles and magnetic carrier.

<Production Example 7 of mixture of inorganic fine particles and magnetic carrier>
0.5 parts by mass of inorganic fine particles 7 shown in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1, and 25 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 3 minutes to obtain a mixture 7 of inorganic fine particles and magnetic carrier.

<Production Example 8 of mixture of inorganic fine particles and magnetic carrier>
To 100.000 parts by mass of magnetic carrier 1, 2.0 parts by mass of inorganic fine particles 8 shown in Table 2 were added, and 25 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 5 minutes to obtain a mixture 8 of inorganic fine particles and magnetic carrier.

<Production Example 9 of mixture of inorganic fine particles and magnetic carrier>
9.5 parts by mass of the inorganic fine particles 8 shown in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1, and 50 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 10 minutes to obtain a mixture 9 of inorganic fine particles and magnetic carrier.

<Production Example 10 of mixture of inorganic fine particles and magnetic carrier>
0.011 parts by mass of the inorganic fine particles 8 shown in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1, and 30 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 5 minutes to obtain a mixture 10 of inorganic fine particles and magnetic carrier.

<Production Example 11 of mixture of inorganic fine particles and magnetic carrier>
10.20 parts by mass of the inorganic fine particles 8 shown in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1, and 70 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 5 minutes to obtain a mixture 11 of inorganic fine particles and magnetic carrier.

<Production Example 12 of mixture of inorganic fine particles and magnetic carrier>
0.0010 parts by mass of the inorganic fine particles 8 shown in Table 2 are added to 100.000 parts by mass of the magnetic carrier 1 and 25 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 5 minutes to obtain a mixture 12 of inorganic fine particles and magnetic carrier.

<Production Example 13 of mixture of inorganic fine particles and magnetic carrier>
To 100.000 parts by mass of magnetic carrier 1, 2.0 parts by mass of inorganic fine particles 9 shown in Table 2 were added, and 25 m was measured using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 5 minutes to obtain a mixture 13 of inorganic fine particles and magnetic carrier.

<Production Example 14 of mixture of inorganic fine particles and magnetic carrier>
To 100.000 parts by mass of the magnetic carrier 1, 2.0 parts by mass of the inorganic fine particles 10 shown in Table 2 are added, and 25 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). For 5 minutes to obtain a mixture 14 of inorganic fine particles and magnetic carrier.

<Production Example 15 of mixture of inorganic fine particles and magnetic carrier>
To 100.000 parts by mass of magnetic carrier 1, 2.0 parts by mass of inorganic fine particles 11 of Table 2 were added, and 15 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 5 minutes to obtain a mixture 15 of inorganic fine particles and magnetic carrier.

<Production Example 16 of mixture of inorganic fine particles and magnetic carrier>
To 100.000 parts by mass of magnetic carrier 1, 2.0 parts by mass of inorganic fine particles 12 of Table 2 were added, and 15 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). For 5 minutes to obtain a mixture 16 of inorganic fine particles and magnetic carrier.

<Production Example 17 of mixture of inorganic fine particles and magnetic carrier>
2.0 mass parts of inorganic fine particles 13 of Table 2 are added to 100.000 mass parts of the magnetic carrier 2, and 15 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). / Min for 5 minutes to obtain a mixture 17 of inorganic fine particles and magnetic carrier.

<Production Example 18 of mixture of inorganic fine particles and magnetic carrier>
To 100.000 parts by mass of magnetic carrier 1, 2.0 parts by mass of inorganic fine particles 14 shown in Table 2 were added, and 15 m using a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). For 5 minutes to obtain a mixture 18 of inorganic fine particles and magnetic carrier.

Example 1
To 90 parts by mass of the magnetic carrier 1 obtained above, 10 parts by mass of toner 1 is added and mixed in a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). It was. This starting developer was introduced into the developing tank.
On the other hand, 9 parts by mass of toner 1 is added to 1 part by mass of mixture 1 of inorganic fine particles and magnetic carrier, and the mixture is replenished by mixing in a V-type mixer in an environment of normal temperature and normal humidity (23 ° C., 50% RH). A developer developer container in the replenishment developer container was filled.
Using these developers, using a Canon full color copier CLC5000 remodeling machine, the toner loading on the initial transfer material (paper: A4 color laser copier paper) is 0.55 mg / cm ^2. The image development evaluation was performed under normal temperature and low humidity (23 ° C., 5% RH) while adjusting the developing bias and replenishing the developer for replenishment. In this environment, 50,000 images were output using a chart with an image area of 5%. Subsequently, 50,000 images were output using a chart having an image area of 25% under a high temperature and high humidity environment (30 ° C., 80% RH). Furthermore, the following evaluation tests 1 to 4 and the dischargeability of the developer for replenishment (replenishability: evaluation test 5) were evaluated.

The modified CLC5000 machine is as follows. First, using a cyan station, a carrier recovery member such as a discharge screw was attached. The laser spot diameter was narrowed down so that it could be output at 600 dpi. The surface layer of the fixing roller of the fixing unit was changed to a PFA tube, and the oil application mechanism was removed.
The evaluation items and evaluation criteria are shown below. The obtained evaluation results are shown in Table 4.

(Evaluation test 1: Evaluation of charge amount)
FIG. 7 is an explanatory diagram of an apparatus for measuring the triboelectric charge amount of the two-component developer. First, in a metal measuring container 52 having a screen 51 having a mesh opening of 30 μm at the bottom, 0.5 to 1.5 g of the two-component developer collected from the sleeve is put and a metal lid 53 is placed. The mass of the entire measurement container 52 at this time is weighed and is defined as W1 (g). Next, in the suction device 54 (at least the insulator is in contact with the measurement container 2), suction is performed from the suction port 55 and the air volume control valve 56 is adjusted to set the pressure of the vacuum gauge 57 to 4 kPa. In this state, the toner is sucked and removed by suction, preferably for about 2 minutes. The potential of the electrometer 58 at this time is set to V (volt). Here, 59 is a capacitor, and the capacity is C (μF). Moreover, the mass of the whole measurement container after suction is weighed and is defined as W2 (g). The triboelectric charge amount (mC / kg) of the toner is calculated according to the following formula.
[Equation 1]
Two-component developer triboelectric charge (tribo) (mC / kg) = C × V / (W1-W2)
Evaluation was performed based on the following evaluation criteria from the obtained triboelectric charge value.
<Evaluation criteria>
A: The difference in tribo between the initial stage and the endurance of 50,000 sheets is less than Δ3.0 (mC / kg). Very good.
B: The difference in tribo between the initial stage and the endurance of 50,000 sheets is good at Δ3.0 or more and less than 5.0 (mC / kg). There is no problem in practical use.
C: Although the tribo difference between the initial stage and the endurance of 50,000 sheets is Δ5.0 or more and less than 7.0 (mC / kg), the charging stability is somewhat difficult, but there is no practical problem.
D: The tribo difference between the initial stage and the endurance of 50,000 sheets is Δ7.0 or more, and there is a problem in charging stability. The color tone variation of the image is conspicuous, which is impractical.

(Evaluation test 2: Evaluation of fog)
After the NL endurance image (room temperature and low humidity (23 ° C., 5% RH)), the fog is measured with a reflectometer (densitometer TC6MC: Tokyo Denki Technical Center). The fog density (%) was calculated from the difference in the whiteness average value of the transfer paper and evaluated. The evaluation criteria are as follows.
<Evaluation criteria>
A: Very good (less than 1.2%)
B: Good (1.2% to less than 2.4%)
C: Normal (2.4% to less than 3.6%)
D: Poor (3.6% or more)

(Evaluation test 3: Evaluation of drum filming and scratches)
After NL endurance image printing (normal temperature and low humidity (23 ° C., 5% RH)), the electrostatic latent image bearing member (drum) filming (Dr filming) and the state of scratches were evaluated.
<Evaluation criteria>
A: There is no scratch that can be confirmed.
B: Although there are scratches of 1 μm or less, there is no problem on the image.
C: Although there are scratches less than 2 μm, there is no problem with the image.
D: There is a scratch of 2 μm or more, which is a problem on the image.

(Evaluation Test 4: Image Flow Evaluation)
After HH endurance image printing (high temperature and high humidity environment (30 ° C., 80% RH)), with the intermediate transfer member released from the photosensitive member in each environment, only the photosensitive member is applied for 30 minutes while applying the charging bias. After rotating, stop, remove the photoconductor from the developer, leave it in a high-temperature and high-humidity environment (40 ° C, 90% RH) overnight, return the developer and the intermediate transfer member to normal, and print characters with a printing ratio of 5%. Output a pattern image. The output images were confirmed, and the following ranking was performed according to the number of output images required for image output until the image flow disappeared.
<Evaluation criteria>
A: Less than 10 sheets B: 10 sheets or more, less than 30 sheets C: 30 sheets or more, less than 50 sheets D: 50 sheets or more

(Evaluation test 5: Evaluation of dischargeability of replenishment developer from replenishment developer container)
The replenishment developer container is filled with a replenishment developer in an amount of 0.43 g / cc with respect to the inner volume of the container, the container is rotated at a speed of 17 m / s, and the discharge property is visually confirmed.
<Evaluation criteria>
A: Total discharge.
B: Almost all discharged. Some residual replenishment developer in dead space.
C: Residual developer is present on the inner wall.
D: The opening is blocked and blocking occurs.

  In this example, a 50,000 sheet durability test was performed using a 5% chart in a normal temperature and low humidity environment. The fluctuation in the triboelectric charge amount of the toner before and after the durability test was Δ is less than 3, and fogging was 0 throughout the durability test. Less than 7%, no deposits on the drum and no scratches on the drum were observed. In addition, even in accelerated evaluation with a photoconductor in a severe leaving environment of 40 ° C. and 90% RH after endurance under high temperature and high humidity, no image flow was observed and very good results were obtained. Further, the discharging performance of the replenishment developer was good.

<Examples 2 to 19>
In Example 1, instead of toner 1 and magnetic carrier 1 as a starting developer, toner and magnetic carrier or a mixture of inorganic fine particles and magnetic carrier as shown in Table 4 are used, and toner 1 is used as a replenishing developer. In addition, instead of the mixture 2 of the inorganic fine particles and the magnetic carrier, a replenishment developer prepared by mixing the toner and the mixture of the inorganic fine particles and the magnetic carrier as shown in Table 4 with the mixing ratio shown in Table 4 was used. Images were drawn out in the same manner as in Example 1, and evaluation tests 1 to 5 were conducted. The evaluation results are shown in Table 4.

<Examples 20 to 23>
In Example 1, a full color copying machine IRC3220N manufactured by Canon Inc. was used as an image forming apparatus, 200 g of a start developer was added to the developing tank, and a carrier recovery member such as a discharge screw was attached to the developing device. Otherwise, the image was drawn out in the same manner as in Example 1, and evaluation tests 1 to 5 were conducted. The obtained evaluation results are shown in Table 5. In the table below, “carrier” means “magnetic carrier” or “mixture of inorganic fine particles and magnetic carrier”.

<Comparative Examples 1-6>
Except that the start developer and the replenishment developer shown in Table 5 were used, the image was drawn out in the same manner as in Example 20, and evaluation tests 1 to 5 were performed. The obtained evaluation results are shown in Table 5.

1 is a schematic configuration diagram showing an embodiment of a full-color image forming apparatus in which the replenishment developer of the present invention is used. FIG. 2 is an enlarged configuration diagram of a developing device used in the image forming apparatus of FIG. 1. FIG. 2 is an enlarged configuration diagram of a developing device used in the image forming apparatus of FIG. 1. 1 is a schematic configuration diagram showing an embodiment of a full-color image forming apparatus in which the replenishment developer of the present invention is used. Schematic diagram showing the flow of developer in the image forming apparatus using the replenishment developer. It is a schematic block diagram of the apparatus which measures the specific resistance value of a magnetic carrier, a nonmagnetic inorganic compound, and a magnetic body. It is explanatory drawing of the apparatus which measures the triboelectric charge amount of a two-component developer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 2,3,4,5 Developer 6 Developing sleeve 7 Restriction blade 8 Magnet roll 9 Replenishment developer accommodating device 10, 11 Developer conveying screw 12 Transfer material 13 Developing device 14 Exposure device 15 Charging rollers 16, 19 , 22, 33 Static eliminating device 17 Developing tank 18, 23 Cleaning device 20 Conveying guide member 21 Fixing device 24 Transfer drum 25 Registration roller 26, 27 Paper feed trays 28, 29 Feeding roller 30 Opposing roller 31 Transfer device 32 Adsorbing device 34 Development Developer discharge port 35 Developer recovery port 36 Communication pipe 37 Developer primary storage unit 38 Developer recovery auger Pa, Pb, Pc, Pd Image forming unit 61a Photoconductor 62a Charge roller 63a Developer 64a Transfer blade 65a Replenishment developer container 67a Exposure light 68 Transfer material carrier 69 Separation charger 70 Fixing device 71 Fixing roller 72 Pressure rollers 75 and 76 Heating means 79 Cleaning device 80 Driving roller 81 Belt driven roller 82 Belt neutralizer 83 Registration roller 85 Toner concentration detection sensor 101 Replenishment developer container 102 Developer 103 Cleaning device 104 Developer collection container 41 Lower electrode 42 Upper electrode 43 Insulator 44 Ammeter 45 Voltmeter 46 Constant voltage device 47 Magnetic carrier 48 Guide ring E Resistance measurement cell
L Sample thickness 51 Conductive screen 52 Measuring container 53 Metal lid 54 Suction machine 55 Suction port 56 Air flow control valve 57 Vacuum gauge 58 Electrometer 59 Condenser

Claims (8)

This is a replenishment developer for use in a two-component development method in which an electrostatic charge image is developed while replenishment developer is replenished to the developing unit, and at least the excess carrier inside the developing unit is discharged from the developing unit. And
The replenishment developer contains at least a toner, inorganic fine particles, and a magnetic carrier,
The inorganic fine particles have a number average particle diameter (D1) of 50 to 300 nm,
The replenishment developer is prepared by mixing the inorganic fine particles and the magnetic carrier in advance and then mixing with toner.   The replenishing developer according to claim 1, wherein the inorganic fine particles contain one or more elements selected from magnesium, calcium, strontium, barium and cerium.   The replenishing developer according to claim 1, wherein the inorganic fine particles are at least one selected from magnesium silicate, calcium titanate, strontium titanate, barium titanate, and cerium oxide.   The replenishment developer according to claim 1, wherein the inorganic fine particles contain silicon nitride.   The replenishment developer according to any one of claims 1 to 4, wherein the inorganic fine particles are mixed in a mass ratio of 0.01 to 10 parts by mass with respect to 100 parts by mass of the magnetic carrier. .   The replenishment developer according to any one of claims 1 to 5, wherein the replenishment developer contains toner in a mass ratio of 2 to 50 parts by mass with respect to 1 part by mass of the magnetic carrier. .   A two-component developing method for developing an electrostatic charge image while replenishing the replenishment developer to the developing device, and discharging at least the excess carrier inside the developing device from the developing device. A developing method using the replenishing developer according to any one of the above. A method for producing a replenishment developer for use in a two-component development method in which a replenishment developer is developed while being replenished to a developing unit, and at least an excess carrier inside the developing unit is discharged from the developing unit. ,
The replenishment developer contains at least a toner, inorganic fine particles, and a magnetic carrier,
The inorganic fine particles have a number average particle diameter (D1) of 50 to 300 nm,
A method for producing a replenishment developer, wherein the inorganic fine particles and the magnetic carrier are mixed in advance and then mixed with toner.

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