JP2000019753A - Image forming method, process cartridge, and image forming toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate image-flowing in high temperature high humidity surroundings even when any transfer material is used, and to prevent drum fusion and stripes from being generated in all the circumstance. SOLUTION: In this image forming method, an electrostatic image is formed on an electrostatic charge image carrier 1, the electrostatic image is developed with toner 13 held in a developing means 4 to develop a toner image, the toner image on the carrier 1 is transfered to a transfer material P, and the toner image on the transfer material P is fixed by a fixing means 12. A surface layer of the carrier 1 contains (1) at least one kind out of polyarylate resins having 7.5×103-3.7×104 of weight-average molecular weight and having a specific constitutional unit, or polycarbonate resins having 7.5×103-3.7×104 of weight-average molecular weight and having a specific constitutional unit, and (2) fluororesin particles. The toner 13 contains toner particles, a first inorganic fine pulverulent body having 0.10 μm or less of number-average particle size, and the second inorganic fine pulverulent body having 0.12 μm-3.0 μm of number- average particle size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic technology, and more particularly to an image forming method and a process cartridge using an electrostatic image developing toner (hereinafter referred to as "toner") for developing an electrostatic latent image. About.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, Japanese Patent Publication No. Sho 42
Although many methods are known as described in JP-A-23910 and JP-B-43-24748,
Generally, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means, and then the latent image is developed with toner to form a visible image, and if necessary, transferred to paper or the like. After transferring the toner image to the material, the toner image is fixed on the transfer material by heat, pressure or the like to obtain a copy. Further, the toner remaining without being transferred onto the photoconductor is cleaned by various methods, and the above-described steps are repeated.

In recent years, as a device using electrophotography, a digital printer as an output of a computer as well as copying an original document has appeared. One of the digital printers is a laser beam printer. Laser beam printers are generally used in offices at room temperature and humidity, but in Southeast Asia,
In some regions, such as India, it is used in hot and humid environments. In such an environment, a phenomenon (hereinafter, referred to as "image deletion") in which a latent image on the surface of the photoreceptor is significantly damaged by a low electric resistance substance formed by paper dust, ozone, or the like generated during printing is likely to occur.

As means for preventing image deletion, Japanese Unexamined Patent Publication No.
Japanese Patent Application Publication No. 0-326060 discloses a toner containing inorganic fine powder having two types of BET. Japanese Patent Application Laid-Open No. 62-16 / 1987 discloses a means for preventing image deletion of a photosensitive member.
No. 0458 discloses a photosensitive member having a photosensitive layer containing two kinds of polycarbonate resins having different molecular weights. However, when the above-described toner is used, although image deletion is certainly improved, a phenomenon in which fine particles due to the toner are pressed by a charging member or the like and adheres to the photoreceptor (hereinafter, referred to as “drum fusion”). Becomes apparent. The same effects and adverse effects are likely to occur when a photoreceptor having two types of photosensitive layers having different molecular weights is used.

On the other hand, the degree of occurrence of the image deletion phenomenon varies depending on the type of paper used as a transfer material. In particular, in the case of paper using talc as a filler, it is difficult to prevent image deletion even when the toner having the above two types of inorganic fine powders is used alone. However, the fusion of the drum is further deteriorated, and a new problem arises in that streaks are formed on the drum surface and white streaks (hereinafter referred to as "white streaks") appear on the image.

[0006] This white streak tends to occur particularly remarkably when a resin having a relatively small molecular weight is used.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming method, a process cartridge and an image forming toner in which image transfer does not occur in any high-temperature and high-humidity environment using any transfer material. is there.

Another object of the present invention is to provide an image forming method, a process cartridge, and an image forming toner in which drum fusion does not occur in all environments.

Another object of the present invention is to provide an image forming method, a process cartridge and an image forming toner which do not cause white streaks in all environments.

[0010]

According to the present invention, there is provided an electrostatic image carrier for carrying an electrostatic image for carrying an electrostatic image, and the electrostatic image carrier is charged on the charged electrostatic image carrier. A charge image is formed, the electrostatic image is developed with a toner included in the developing unit to form a toner image, and the toner image on the electrostatic image carrier is transferred to a transfer material with or without an intermediate transfer member. An image forming method in which a toner image on a transfer material is fixed by a fixing unit, wherein the electrostatic image carrier has a surface layer having a weight average molecular weight of 7.5 × 10 ^{3 to} 3.7 × 10 ^4. Having the following formula (1)

[0011]

Embedded image Wherein, X ₁ is -CR ₁₃ R ₁₄ - (provided that R ₁₃ and R ₁₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{1 to} R ₁₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Or a polyarylate resin having a structural unit represented by the formula:
Formula (2) having a weight average molecular weight of ^{3 to} 3.7 × 10 ⁴

[0012]

Embedded image [Wherein, X ₂ is -CR ₂₃ R _24- (where R ₂₃ and R ₂₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{15 to} R ₂₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. The toner contains at least one kind of polycarbonate resin having a structural unit represented by the formula (I) and fluorine-based resin particles, and the toner comprises: toner particles; a first inorganic fine powder having a number average particle size of 0.10 μm or less; A second inorganic fine powder having a particle size of 0.12 to 3.0 μm.

According to the present invention, there is provided a process cartridge detachably mounted on an image forming apparatus main body, wherein the process cartridge has an electrostatic image carrier for carrying an electrostatic image, and the electrostatic image carrier. And a developing unit for holding a toner for forming a toner image by developing an electrostatic image carried on the electrostatic image. The electrostatic image carrier has a surface layer of 7.5 × 10 ^3. The following formula (1) having a weight average molecular weight of from 3.7 to 10 ⁴

[0014]

Embedded image Wherein, X ₁ is -CR ₁₃ R ₁₄ - (provided that R ₁₃ and R ₁₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{1 to} R ₁₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Or a polyarylate resin having a structural unit represented by the formula:
Formula (2) having a weight average molecular weight of ^{3 to} 3.7 × 10 ⁴

[0015]

Embedded image [Wherein, X ₂ is -CR ₂₃ R _24- (where R ₂₃ and R ₂₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{15 to} R ₂₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. The toner contains at least one kind of polycarbonate resin having a structural unit represented by the formula (I) and fluorine-based resin particles, and the toner comprises: toner particles; a first inorganic fine powder having a number average particle size of 0.10 μm or less; A second inorganic fine powder having a particle size of 0.12 to 3.0 μm.

Further, the present invention provides a compound of the following formula (1) having a weight average molecular weight of 7.5 × 10 ^{3 to} 3.7 × 10 ^4.

[0017]

Embedded image Wherein, X ₁ is -CR ₁₃ R ₁₄ - (provided that R ₁₃ and R ₁₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{1 to} R ₁₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Or a polyarylate resin having a structural unit represented by the formula:
Formula (2) having a weight average molecular weight of ^{3 to} 3.7 × 10 ⁴

[0018]

Embedded image [Wherein, X ₂ is -CR ₂₃ R _24- (where R ₂₃ and R ₂₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{15 to} R ₂₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. The electrostatic image carrier having a surface layer containing at least one kind of polycarbonate resin having the structural unit represented by formula (1) and fluorine-based resin particles to form an electrostatic image on the charged electrostatic image carrier. Developing the electrostatic image with the toner of the developing unit to form a toner image, transferring the toner image on the electrostatic image carrier to a transfer material with or without an intermediate transfer member, In an image forming toner used in an image forming method for fixing a toner image by a fixing unit,
The toner has toner particles and a number average particle diameter of 0.10 μm.
m and the first inorganic fine powder having a number average particle size of 0.12 or less.
And a second inorganic fine powder having a thickness of from 3.0 to 3.0 μm.

The electrostatic image carrier used in the present invention comprises a resin having an appropriate abrasion as a resin forming the surface layer and fluorine-based resin particles which reduce the friction coefficient of the surface and improve the durability. By doing so, it is possible to maintain excellent durability characteristics and have good electrophotographic characteristics for preventing image deletion.

In general, the strength of the resin decreases as the molecular weight decreases, and the durability decreases accordingly. However, in the present invention, the resin is combined with fluorine resin particles which can improve the durability by reducing the surface friction coefficient. This makes it possible to achieve an electrophotographic photoreceptor having excellent durability characteristics and good image flow prevention. This is because the fluororesin particles themselves may be effective for adhering to the surface, but in addition to these, there are resins with lower molecular weight that are excellent in abrasion and fluororesin particles that are effective in reducing the coefficient of friction. By using in combination, the surface is worn more smoothly than in the past, and as a result, it is difficult to attach the charged deteriorated surface deposits, etc., which are considered to be a cause of image deletion. it is conceivable that.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION The polyarylate resin having a structural unit represented by the formula (1) and the polycarbonate resin represented by the formula (2) used in the present invention need to be capable of imparting appropriate abrasion properties. . Specifically, 7
Having a weight average molecular weight of 500 to 37000,
It preferably has a weight average molecular weight of from 00 to 37000, more preferably from 7500 to 30000. If the weight average molecular weight is less than 7500, the strength is too large to cause damage due to repeated use, and further, the effect on image deletion is insufficient due to the influence. The weight average molecular weight is 3
If it is larger than 7000, an appropriate abrasion cannot be provided, and the effect on image deletion becomes insufficient. The degree of dispersion of these resins is preferably 3.0 or less, more preferably 2.6 or less. When the degree of dispersion is greater than 3.0, the proportion of those having a smaller molecular weight increases, causing a decrease in strength. As a result, scratches are liable to be caused by repeated use, and further, the effect on image deletion due to the effect is also reduced. Tends to be insufficient. The “dispersion degree” here is a value represented by weight average molecular weight / number average molecular weight.

The molecular weight in the present invention is measured by GPC (gel permeation chromatography) using polystyrene as a standard substance. Examples of more detailed measurement conditions are shown below. Apparatus: HLC-8120 (manufactured by Tosoh Corporation) Column: TSKgel Super HM-M 6 mm D. × 15 cm (manufactured by Tosoh Corporation) Standard material: polystyrene (manufactured by Tosoh Corporation) Sample: 1 part by weight of resin / 1000 parts by weight of tetrahydrofuran Flow rate: 0.6 ml / min Solvent: tetrahydrofuran Temperature: 40 ° C. Detector: R. I, UV (254 nm)

In the formulas (1) and (2), examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a cyclohexyl group and a cycloheptyl group. Examples of the aryl group include a phenyl group, a naphthyl group and an anthryl group. Examples of the cycloalkylidene group include a cyclohexylidene group, a cycloheptylidene group, and a fluorenylidene group. Examples of the α, ω-alkylene group include a 1,2-ethylene group, a 1,3-propylene group, and a 1,4-butylene group. Examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom.

Substituents which these groups may have include halogen atoms such as fluorine, chlorine and bromine; alkyls such as methyl, ethyl and propyl; phenyl, naphthyl and anthryl Aryl groups such as benzyl group and phenethyl group; and alkoxy groups such as methoxy group, ethoxy group and propoxy group.

The "single bond" means that the benzene rings on both sides of X ₁ or X ₂ are directly bonded. For example, the following structural unit examples (1) -7, (1) -23 and (1)
-24.

Specific examples of the structural units of the polyarylate resin having the structural unit represented by the formula (1) used in the present invention are shown in Tables 1 to 4, but are not necessarily limited thereto.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

[0030]

[Table 4]

Preferred examples are structural unit examples (1)-
1, (1) -2, (1) -3, (1) -4, (1) -9
And especially the structural units (1) -1, (1) -2,
(1) -4 is preferred.

The polyarylate resin having a constitutional unit represented by the formula (1) used in the present invention is usually a terephthalic acid chloride or an isophthalic acid chloride to improve the solubility of the bisphenol represented by the following formula (3). It can be synthesized by stirring the mixture and an alkali in a solvent / water system and performing interfacial polymerization.

[0033]

Embedded image Wherein, X ₁ is -CR ₁₃ R ₁₄ - (provided that R ₁₃ and R ₁₄
Are the same or different and are a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω
-Alkylene group, single bond, -O-, -S-, -SO-,
Or —SO ₂ —. R _{1 to} R ₈ are the same or different and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. ]

The ratio of terephthalic acid chloride and isophthalic acid chloride is determined in consideration of the solubility of the polymer and is not defined. However, any chloride is 30 mol
It is necessary to pay attention that the solubility of the synthesized polymer is extremely reduced when the content is less than 10%. Usually, it is preferable to synthesize at a ratio of 1/1.

Further, in the electrostatic image carrier of the present invention, even if the polymer is constituted by the same structural unit represented by the formula (1), two or more different types represented by the formula (1) may be used. Copolymers composed of structural units may be used. Furthermore, equation (1)
You may blend two or more types of resin which has a structural unit shown by these.

Preferred examples of the structural units of the polycarbonate resin having the structural unit represented by the formula (2) used in the present invention are shown in Tables 5 to 8, but are not limited thereto.

[0037]

[Table 5]

[0038]

[Table 6]

[0039]

[Table 7]

[0040]

[Table 8]

Particularly preferred examples are structural unit examples (2) -1, (2) -2, (2) -3, (2) -4,
(2) -9, in particular, the structural unit (2) -1,
(2) -2 and (2) -4 are preferred.

The polycarbonate resin having the structural unit represented by the formula (2) used in the present invention is synthesized by polymerizing a bisphenol represented by the following formula (4) in the presence of phosgene usually in the presence of an alkali. be able to.

[0043]

Embedded image [Wherein, X ₂ is -CR ₂₃ R _24- (where R ₂₃ and R ₂₄
Are the same or different and are a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω
-Alkylene group, single bond, -O-, -S-, -SO-,
Or —SO ₂ —. R _{15 to} R ₂₂ are the same or different and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. ]

In the electrostatic image carrier used in the present invention, a polymer composed of the same structural unit represented by the formula (2) or two or more different types represented by the formula (2) may be used. Copolymers composed of structural units may be used. Furthermore, two or more of these resins may be blended, or may be blended with the resin represented by the formula (1).

In the electrostatic image carrier used in the present invention, if necessary, it may be mixed with a resin having a relatively large molecular weight to maintain film strength. As the resin to be used, a polyarylate resin represented by the formula (1) or a polycarbonate resin represented by the formula (2) is preferable. Specifically, the molecular weight of the resin preferably has a weight average molecular weight greater than 37000, Especially 5
It preferably has a weight average molecular weight of 0000 to 300,000.

Further, if necessary, it may be used by mixing with other resins. However, 7.5 × 10 ^{3 to} 3.7 × 10 ⁴
When the resin of the present invention having a weight-average molecular weight of 3 and another resin is mixed, the resin of the present invention is preferably contained in an amount of 20% by weight or more, and more preferably 30% by weight or more based on the whole binder resin. More preferably.
If the amount is less than 20% by weight, it is difficult to impart a suitable abrasion, and the effect on image deletion tends to be insufficient.

The fluororesin particles used in the present invention include ethylene tetrafluoride resin, ethylene trifluoride resin,
It is desirable to appropriately select one or more types selected from propylene fluoride resin, vinyl fluoride resin, vinylidene fluoride resin, difluorinated ethylene chloride resin and copolymers thereof. Resins and vinylidene fluoride resins are preferred. The molecular weight of the resin can be appropriately selected and is not particularly limited.

The content of the fluororesin particles is 0.1 to 50% by weight based on the total solid weight in the layer containing the particles.
Is suitable, and particularly preferably 0.2 to 30% by weight. When the content is less than 0.1% by weight, the modifying effect by dispersion of the fluororesin particles is not sufficient. On the other hand, when the content is more than 50% by weight, the long-term stability of the coating material deteriorates, the light transmittance decreases, This causes a decrease in mobility.

In the present invention, the primary particle size of the fluororesin particles is 0.3 μm or less, preferably 0.05 to 500 μm.
The thickness is preferably 0.3 μm, more preferably 0.08 to 0.3 μm. 0.3μ primary particle size of fluorine resin particles
If it is greater than m, the electrostatic image carrier according to the present invention uses a binder resin having a relatively low molecular weight, so that sedimentation of the fluorine-based resin particles in the coating solution tends to occur, and the long-term stability of the coating material The adverse effect that the properties and coating properties are deteriorated occurs. Primary particle size of fluorine resin particles is 0.05μm
If it is less than the above range, it becomes difficult to obtain the effect of adding the particles.

In order to improve the dispersibility of the fluorine-based resin particles, it is more preferable to use a fluorine-based comb-type graft polymer. The fluorine-based comb-type graft polymer has a molecular weight of 1000 having a polymerizable functional group at one end of each molecular chain.
It is obtained by copolymerizing an oligomer having a relatively low molecular weight of about 10000 and a fluoropolymerizable monomer,
It has a structure in which a macromonomer polymer is hung in a branch shape on a fluorine-based polymerizable trunk. As the macromonomer, those having an affinity for the resin to which the graft monomer is added are selected, and for example, polymers or copolymers of acrylates, methacrylates, styrene compounds, and the like are used.

On the other hand, as the fluorine-based polymerizable monomer,
One or more polymerizable monomers having a fluorine atom in the side chain as shown in Table 9 are used, but are not limited thereto.

[0052]

[Table 9]

In the formula, Ra represents _a hydrogen atom or a methyl group. R _b represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or a nitrile group, and may be a combination of several kinds thereof. n is an integer of 1 or more, m is an integer of 1 to 5,
k represents an integer of 1 to 4, and m + k = 5.

In the formula of Table 9, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a cyclohexyl group and a cycloheptyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group and a propoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom.

The content of the fluorine monomer residue in the fluorine-based comb-type graft polymer is preferably 5 to 90% by weight in the fluorine-based comb-type graft polymer.
% By weight is more preferred. When the content of the fluorine-based monomer residue is less than 5% by weight, the effect of improving the hydrophobicity cannot be sufficiently exhibited, and when the content of the fluorine-based monomer residue exceeds 90% by weight, the solubility with the macromonomer is deteriorated. become worse.

The content of the fluorine-based comb type graft polymer is 0.01 to 20% based on the weight of the fluorine-based resin particles.
Is particularly preferable, and 0.1 to 10% is particularly preferable. 0.01
%, The effect of modifying the dispersibility of the fluororesin particles is not sufficient. On the other hand, if it exceeds 20%, the graft polymer is also present in the bulk of the coating film, so that the compatibility with the resin may cause a problem. When an electrophotographic process is performed, accumulation of residual potential occurs.

In the electrostatic image carrier of the present invention, it is more preferable to add an antioxidant as needed. By adding an antioxidant, it is possible to suppress the oxidative deterioration of the surface deposits and the binder resin, which is the main cause of image deletion, and thus it is possible to more effectively prevent the image deletion.

As the antioxidant used in the present invention, hindered phenol antioxidants and phosphorus antioxidants are particularly preferable. These may be used alone, but it is particularly preferable to use a combination of a hindered phenol antioxidant and a phosphorus antioxidant.

If the content of the antioxidant is too small, the effect on image deletion will be insufficient, while if it is too large, electrophotographic characteristics such as an increase in residual potential will be deteriorated, so it is necessary to select an appropriate amount. is there. Specifically, 0.01 to resin
% By weight to 30% by weight, particularly 0.1% by weight to 2% by weight.
0% by weight is preferred.

Next, an electrophotographic photosensitive member which is a typical example of the electrostatic image carrier used in the present invention will be described.

The electrophotographic photoreceptor contains a charge transport layer containing a charge transport material and a charge generation material even if the photosensitive layer is a single layer type containing a charge transport material and a charge generation material in the same layer. Although a laminated type separated into a charge generation layer may be used, a laminated type is preferable in terms of electrophotographic characteristics. Further, it is preferable that a charge transport layer is provided on the charge generation layer, and the charge transport layer is a surface layer. Hereinafter, this embodiment will be described as an example.

The conductive support to be used may be a conductive support, and may be a metal such as aluminum or stainless steel, or a metal provided with a conductive layer, paper, plastic, or the like. And the like.

When the exposure is coherent light, a conductive layer may be provided on the conductive support for the purpose of preventing interference fringes due to scattering or covering a damage on the support. The conductive layer can be formed by dispersing conductive powder such as carbon black and metal particles in a binder resin. The thickness of the conductive layer is 5 to 4
0 μm, preferably 10 to 30 μm is suitable.

An intermediate layer having an adhesive function may be provided between the conductive support and the photosensitive layer. Examples of the material of the intermediate layer include polyamide, polyvinyl alcohol, polyethylene oxide, ethyl cellulose, casein, polyurethane, and polyether urethane. These are applied by dissolving in an appropriate solvent. The thickness of the intermediate layer is 0.05 to 5μ.
m, preferably 0.3 to 1 μm.

The charge generation layer contains a charge generation material of 0.3 to 4
By applying a homogenizer, ultrasonic dispersion, ball mill, vibrating ball mill, sand mill, attritor, roll mill and liquid collision type high-speed disperser together with a double amount of a suitable resin and solvent, a well-dispersed dispersion and drying. It is formed.

The charge generating materials used include selenium-tellurium, pyrylium, thiapyrylium dyes, phthalocyanines, anthantrones, dibenzopyrene quinones,
Examples include trisazo, cyanine, disazo, monoazo, indigo, quinacridone, and asymmetric quinocyanine pigments. The thickness of the charge generation layer is 5 μm or less, preferably 0.1 to 2 μm.

The charge transport layer is formed by applying and drying a coating solution in which the charge transport material, the resin of the present invention and the fluorine-containing resin particles are dissolved and dispersed in a solvent. As a method of preparing the coating liquid, a charge transport material, a method of simultaneously dissolving and dispersing the resin of the present invention and the fluorine-containing resin particles in a solvent, and a coating liquid in which the resin and the fluorine-containing resin particles are previously dissolved and dispersed. And a method in which the charge transport material is prepared and mixed with a coating solution in which the charge transport material is dissolved. In the preparation of the coating liquid, it may be simple stirring and mixing, but if necessary, using a dispersing means such as a ball mill, a roll mill, a sand mill and a high-pressure disperser, so that the primary particles of the fluorine-containing resin particles are 0.3 μm or less. Mix.

Examples of the charge transporting material used include triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, triarylmethane compounds and thiazole compounds. These charge transporting materials are from 0.5 to
Combined with twice the amount of resin. The thickness of the charge transport layer is 5
４０40 μm, preferably 15-30 μm is suitable.

In the present invention, the toner is fused to the surface of the above-described specific electrostatic image carrier (drum fusion), which causes image defects (black spots and white streaks in the case of reversal development). In terms of prevention, it is preferable to use a specific toner.

That is, the toner particles and the number-average particle diameter are in the range of 0.
It is preferable to use a toner having a first inorganic fine powder of 10 μm or less and a second inorganic fine powder having a number average particle size of 0.12 to 3.0 μm.

The toner particles contain at least a binder resin and a colorant.

Examples of the binder resin of the toner particles used in the present invention include polystyrene; styrene-substituted homopolymers such as poly-p-chlorostyrene and polyvinyltoluene; and styrene-p-chlorostyrene copolymer. Styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile Copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene Styrene copolymer such as copolymer Body: polyvinyl chloride, phenolic resin, natural modified phenolic resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin , Polyvinyl butyral, terpene resin, cumarone indene resin, petroleum resin and the like can be used. Also,
Crosslinked styrenic resins are also preferred binder resins.

As comonomers for the styrene monomer of the styrene copolymer, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, Monocarboxylic acid having a double bond such as methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide or the like; maleic acid, butyl maleate, Dicarboxylic acids having a double bond such as methyl maleate, dimethyl maleate, and the like; vinyl esters such as vinyl chloride, vinyl acetate, and vinyl benzoate; ethylene, propylene, butylene, and the like. Vinyl monomers such as vinyl methyl ketone, vinyl hexyl ketone, etc .; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, etc .; Can be Here, as the cross-linking agent, a compound having two or more polymerizable double bonds is mainly used. Specifically, aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, etc .; ethylene glycol diacrylate, ethylene glycol Glycol dimethacrylate, 1,
Carboxylic acid esters having two double bonds such as 3-butanediol dimethacrylate; divinyl compounds such as divinyl aniline, divinyl ether, divinyl sulfide and divinyl sulfone; and compounds having three or more vinyl groups; Alternatively, they can be used as a mixture.

The binder resin of the toner used for pressure fixing includes low molecular weight polyethylene, low molecular weight polypropylene, ethylene-vinyl acetate copolymer, ethylene-
Acrylic ester copolymers, higher fatty acids, polyamide resins and polyester resins are mentioned. These are preferably used alone or as a mixture.

The colorant that can be used in the toner of the present invention includes any suitable pigment or dye. As the colorant of the toner, a pigment or a dye is used. As the pigment, for example, carbon black, aniline black,
Examples include acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, bengala, phthalocyanine blue, and indanthrene blue. The pigment is used in an amount necessary and sufficient to maintain the optical density of the fixed image. The amount of the pigment is 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by weight, based on 100 parts by weight of the binder resin. . Examples of the dye include an azo dye, an anthraquinone dye, a xanthene dye, and a methine dye. The dye is based on 100 parts by weight of the binder resin.
The addition amount of 0.1 to 20 parts by weight, preferably 0.3 to 10 parts by weight is good. When the toner is a so-called one-component toner containing a magnetic material, the magnetic material may be used as the colorant.

The number average particle diameter of the first inorganic fine powder used in the present invention is 0.10 μm or less, preferably 0.005 to 0.07 μm. The number average particle diameter of the second inorganic fine powder is 0.12 to 3.0 μm.
m, preferably 0.12 to 2.5 μm.

Both the first inorganic fine powder and the second inorganic fine powder have an effect of preventing image deletion in a high-temperature and high-humidity environment, and the effect of the second inorganic fine powder is particularly large. . Further, the second inorganic fine powder has an action of preventing a decrease in image density under a high temperature and high humidity environment.

The first inorganic fine powder is preferably hardly water-soluble, and examples thereof include iron oxide, magnesium oxide, and silicate fine powder. Particularly, silicic acid fine powder is preferable.

The number average particle diameter of the first inorganic fine powder is 0.1
If it is larger than 0 μm, the fluidity of the toner decreases,
Image density tends to decrease. When the number average particle diameter of the first inorganic fine powder is less than 0.005 μm,
Easy release of the first inorganic fine powder from the toner particles,
Filming on the photoreceptor surface is likely to occur.

Further, the surface of the first inorganic fine powder is preferably subjected to a coupling treatment, an oil treatment, a treatment with a fatty acid or the like. Among them, from the viewpoint of drum fusion and prevention of white streaks, those subjected to further oil treatment after the coupling treatment are preferably used, and the amount of oil treatment is 3 to 20% by weight based on the weight of the inorganic fine powder to be treated.
Those containing are preferred. When the amount is less than 3% by weight, the effect of preventing drum fusion and drum white streaks is hardly exhibited, and when the amount is more than 20% by weight, image deletion tends to occur, which is not preferable.

As the oil, a silicone oil is preferably used.

The second inorganic fine powder is preferably hardly water-soluble in order not to lower the chargeability of the toner in a high-temperature and high-humidity environment. For example, iron oxide, chromium oxide, calcium titanate, and strontium titanate are preferable. , Barium titanate, magnesium titanate, cerium oxide, zirconium oxide, aluminum oxide, titanium oxide, zinc oxide, calcium oxide and the like. Strontium titanate, cerium oxide and titanium oxide are preferably used.

The number average particle diameter of the second inorganic fine powder is 0.1
When it is smaller than 2 μm, the effect of preventing image deletion is reduced, and when it is larger than 3.0 μm, a white streak image is easily generated, which is not preferable.

The average particle diameter of the first inorganic fine particles and the second inorganic fine particles is a value measured by the following method.

Electron microscope S-800 (manufactured by Hitachi, Ltd.)
, The first inorganic fine particles are 10,000 to 2000
A photograph was taken at a magnification of 1000 to 20,000 times for the 0x and second inorganic fine particles, and the first inorganic fine particles for the particles having a size of 0.001 µm or more
For the inorganic fine particles of 0.005 μm or more, randomly extract 100 to 200 particles, measure the diameter of each using a measuring instrument such as a caliper, and average the average particle size of each inorganic fine particle. And

In the present invention, the content of the first inorganic fine powder is preferably 0.5 to 2.5% by weight based on the toner. If the amount is less than 0.5% by weight, it becomes difficult to impart sufficient fluidity to the toner, and it becomes difficult to obtain an image density. If the amount exceeds 2.5% by weight, deterioration of drum fusion becomes apparent. The content of the second inorganic fine powder is preferably from 0.35 to 3.5% by weight based on the toner. 0.3
If the amount is less than 5% by weight, a sufficient polishing effect cannot be obtained, and image deletion tends to occur. If the amount is more than 3.5% by weight, deterioration of drum fusion becomes apparent.

In order to achieve the object of the present invention more favorably, the particle size distribution of the toner should be such that the weight average particle size of the toner is 3.5 μm to 6.5 μm, and 2.00
It is preferable that the content of particles having a particle size of 3 to 3.17 μm is 5 to 40% by number. When the weight average particle size of the toner is smaller than 3.5 μm, drum fusion tends to occur, which is not preferable. When it is larger than 6.5 μm, image deletion easily occurs, which is not preferable. When the content of particles having a particle diameter of 2.00 to 3.17 μm is less than 5% by number, image deletion is liable to occur, and when it is more than 40% by number, drum fusion tends to occur. Not preferred.

The weight average particle size and the particle size distribution of the toner are measured using a Coulter Counter TA-II type (manufactured by Coulter), but a Coulter Multisizer (manufactured by Coulter) can also be used. As the electrolytic solution, a 1% NaCl aqueous solution is prepared using primary sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used.

Specifically, the aqueous electrolytic solutions 100 to 15
In 0 ml, 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample was suspended was subjected to dispersion treatment for about 1 to 3 minutes using an ultrasonic disperser, and the volume and the number of toner particles having a size of 2.00 μm or more were measured by using the measuring device with a 100 μm aperture. The distribution and number distribution were calculated. Then, the weight-average particle diameter (D ₄ ) obtained from the volume distribution according to the present invention (the median value of each channel is a representative value for each channel), and the number-based particle diameter 2 obtained from the number distribution The ratio of 0.00 μm to 3.17 μm was determined.

The channels are 2.00 to 2.52
less than 2.5 μm; less than 2.52 to 3.17 μm;
4. less than 4.00 μm; 4.00 to less than 5.04 μm;
04 to less than 6.35 μm; 6.35 to less than 8.00 μm; 8.00 to less than 10.08 μm; 10.08 to 1
2.70 μm or less; 12.70 to less than 16.00 μm;
16.00 to less than 20.20 μm; 20.20 to 25.
Less than 40 μm; 25.40 to less than 32.00 μm; 3
13 channels of 2.00 to less than 40.30 μm are used.

As the toner used in the present invention, those containing a magnetic substance are preferably used. Examples of the magnetic substance include elements such as iron, cobalt, nickel, copper, magnesium, manganese, aluminum and silicon. Metal oxides. Among them, those mainly containing iron oxide such as triiron tetroxide and γ-iron oxide are preferable. Further, from the viewpoint of improving the fluidity of the toner and controlling the chargeability, it is preferable to contain a silicon atom. In particular, when the toner particles have a small diameter, the fluidity of the toner particle base is reduced. Therefore, sufficient fluidity cannot be obtained only by adding the inorganic fine powder of the present invention described above, and good chargeability cannot be obtained. It may be difficult to achieve the above objective. The content of silicon atoms is preferably 0.2 to 2.0% by weight with respect to the magnetic material. If the content is less than 0.2% by weight, sufficient fluidity cannot be obtained, and the character sharpness may not be obtained. There are adverse effects such as deterioration and solid black density. If the content is more than 2.0% by weight, the image density tends to decrease particularly in a high temperature and high humidity environment. The content of silicon atoms is more preferably 0.3 to 1.7% by weight. In particular, it is more preferable that silicon atoms are present at 0.05 to 0.5% by weight on the surface of the magnetic material.

The silicon atom may be added in the form of a water-soluble silicon compound when the magnetic substance is formed. After the formation, filtration and drying of the magnetic substance, the silicon atom is added in the form of a silicate compound and fixed to the surface by a mix muller or the like. You may. These magnetic particles preferably have a BET specific surface area measured by a nitrogen adsorption method of 2 to 3 times.
0 m ² / g is good, and especially 3 to 28 m ² / g is good. Further, magnetic particles having a Mohs hardness of 5 to 7 are preferred.

The shape of the magnetic particles includes an octahedron, a hexahedron, a sphere, a needle, a scale, and the like, and an octahedron, a hexahedron, a sphere, an irregular shape, or the like having a small anisotropy is preferable.
In particular, it is preferable that the sphericity 磁性 of the magnetic particles be 0.8 or more in order to increase the image density. The average particle size of the magnetic particles is preferably 0.05 to 1.0 μm, more preferably 0.1 to 0.6 μm, and particularly 0.1 to 0.4 μm.
m is preferred.

The content of the magnetic substance in the toner is 30 to 200 parts by weight, preferably 60 to 200 parts by weight, and more preferably 70 to 150 parts by weight based on 100 parts by weight of the binder resin. If the amount is less than 30 parts by weight, the transferability is poor, the toner layer on the developer carrier tends to be uneven, and the image tends to be uneven, and the image density tends to decrease due to the increase in the tribo of the magnetic toner. Tend. On the other hand, when the content of the magnetic substance exceeds 200 parts by weight, the fixing property tends to decrease.

The toner used in the present invention preferably uses an organometallic compound as a charge control agent. Among the organometallic compounds, those containing an organic compound which is particularly highly vaporizable and sublimable as a ligand and a counter ion are useful.

As such a metal complex, there is an azo-based metal complex represented by the following formula.

[0097]

Embedded image

In the formula, M represents a coordination center metal, and Cr, Co, Ni, Mn, Fe, Al, Ti, S
c, V and the like. Ar is an aryl group, such as a phenyl group or a naphthyl group, and may have a substituent. Examples of the substituent in this case include a nitro group, a halogen group, a carboxyl group, an anilide group, an alkyl group having 1 to 18 carbon atoms, and an alkoxy group. X, X ', Y,
Y 'is -O-, -CO-, -NH-, -NR- (R is an alkyl group having 1 to 4 carbon atoms). K ⁺ is a hydrogen ion,
It represents a sodium ion, a potassium ion, an ammonium ion, an aliphatic ammonium ion or a mixed ion of any of these.

Hereinafter, specific examples of the complex which is preferably used in the present invention will be shown.

[0100]

Embedded image

[0101]

Embedded image

[0102]

Embedded image

The charge control agent is preferably added in the range of 0.2 to 5 parts by weight based on 100 parts by weight of the toner.

In the present invention, the following waxes are preferably contained in the toner particles from the viewpoint of improving the releasability from the fixing member and improving the fixing property. Paraffin wax and its derivatives, microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, carnauba wax and its derivatives, etc. Derivatives include oxides and block copolymers with vinyl monomers , Graft-modified products.

As other additives, alcohols, fatty acids, acid amides, esters, ketones, hydrogenated castor oil and derivatives thereof, vegetable waxes, animal waxes, mineral waxes, petrolactam and the like can also be used.

To prepare the toner used in the present invention,
A known method is used. For example, a binder resin, a wax, a metal salt or a metal complex, a pigment, a dye, or a magnetic substance as a colorant, a charge control agent, if necessary, and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. After mixing, melt-knead using a hot kneader such as a heating roll, kneader, or extruder to disperse or disperse the metal compounds, pigments, dyes, and magnetic materials in the resin, and then cool. After solidification, pulverization and classification are performed to obtain toner particles according to the present invention.
In the classification step, it is preferable to use a multi-division classifier in terms of production efficiency.

The external additive composed of silica or the like is used in an amount of about 1 to 1 with respect to 100 parts by weight of the toner particles obtained in the classification step.
The addition and mixing in the range of 0 parts by weight is the external addition mixing step. Preferable examples of the apparatus used in the external addition mixing step include a Henschel mixer manufactured by Mitsui Miike Kakoki Co., Ltd. having a name such as FM-500, -300, -75, or -10.

Further, an example of the image forming apparatus is schematically shown in FIG. 1, and an image forming method will be described based on the schematic.

Reference numeral 1 denotes a drum-shaped electrostatic latent image carrier, around which a charging roller (charging member) of a primary charging unit, an exposure optical system 3, a developing unit 4 having a toner carrier 5, and a transfer unit. Means 9 and cleaning means 11 are arranged.

In this image forming apparatus, the surface of the electrostatic latent image carrier 1, which is a photosensitive member, is uniformly charged by the charging roller 2, and then exposed by the exposure optical system 3 to expose the electrostatic latent image carrier 1. To form an electrostatic latent image on the surface of the substrate.

The shape of the charging member used in the present invention is not particularly limited as long as it is a contact charging member that is arranged in contact with the electrostatic image carrier, and the shape is not limited.
Any of a blade shape and a brush shape may be used.

The voltage applied to the charging member is preferably such that the DC voltage has an absolute value of 200 to 2000 V, and the AC voltage has a peak-to-peak voltage of 400 to 4000 V.
Preferably, the frequency is between 200 and 3000 Hz.

Next, a toner coat layer is formed by a toner layer thickness regulating member 6 on the surface of the toner carrier 5 containing a magnet, and the conductive substrate of the electrostatic latent image carrier 1 and the toner carrier are formed in the developing section. The electrostatic latent image formed on the electrostatic latent image carrier 1 is developed while applying an alternating bias, a pulse bias and / or a DC bias by the bias applying means 8 between the electrostatic latent image carrier 1 and the body 5. In the figure, 7 is a stirring means, and 13 is a magnetic toner.

The developed toner image is conveyed to the transfer paper P, and a transfer roller 9 as a transfer means and a voltage application means 10 are applied with a charge having a polarity opposite to that of the toner from the back surface of the transfer paper P. Is electrostatically transferred to

The transfer paper P on which the toner image has been transferred passes through the heating and pressing roller fixing device 12, and the toner image becomes a fixed image.

The toner remaining on the latent image carrier after the transfer step is removed by a cleaning blade 11 as a cleaning means and collected by a cleaner 14, and the steps following primary charging are repeated again.

In the present invention, a process cartridge is constructed by integrally combining a plurality of components, such as the drum-shaped electrostatic image carrier, the developing device, and the cleaning means, as an apparatus unit. The process cartridge may be configured to be detachable from the apparatus main body. For example, a process cartridge is formed by integrally supporting the charging member and the developing device together with the electrostatic image carrier,
A single unit that is detachable from the apparatus main body may be used, and the unit may be detachable using a guide unit such as a rail of the apparatus main body. At this time, the above process cartridge may be provided with a cleaning unit.

FIG. 2 shows an embodiment of the process cartridge of the present invention. In this embodiment, a process cartridge 16 in which a developing unit 4, a drum-shaped electrostatic image carrier (photosensitive drum) 1, a cleaner 14 having a cleaning blade 11, and a primary charging member 2 are integrated is exemplified. In this process cartridge, the developing means 4
When the magnetic toner 13 has run out, the cartridge is replaced with a new cartridge.

In this embodiment, the developing means 4 is the magnetic toner 1
3, a predetermined electric field is formed between the electrostatic image carrier 1 and the developing sleeve 5 as a toner carrier during development. In order for the development process to be performed properly,
The distance between the electrostatic image carrier 1 and the developing sleeve 5 is very important.

In the process cartridge shown in FIG. 2, the developing means 4 has a toner container 15 for containing the magnetic toner 13 and the magnetic toner 13 in the toner container 15 facing the electrostatic image carrier 1 from the toner container 15. A developing sleeve 5 that carries and conveys the toner to the developing area, and an elasticity as a toner layer thickness regulating member for regulating the magnetic toner conveyed to the developing area to a predetermined thickness and forming a thin toner layer on the developing sleeve. And a blade 6.

The developing sleeve 5 can have any structure. Usually, it comprises a non-magnetic developing sleeve 5 containing a magnet (not shown). The developing sleeve 5 may be a cylindrical rotating body as shown. It is also possible to adopt a belt shape that moves in a circulating manner. Usually, aluminum or SUS is preferably used as the material.

The elastic blade 6 is made of a rubber elastic material such as urethane rubber, silicone rubber or NBR; a metal elastic material such as phosphor bronze or a stainless steel plate; a resin elastic material such as polyethylene terephthalate or high density polyethylene. It is composed of boards. The elastic blade 6 is brought into contact with the developing sleeve 5 by the elasticity of the member itself, and the toner container 15 is supported by a blade supporting member made of a rigid body such as iron.
Fixed to The elastic blade 6 has a linear pressure of 5 to 80 g / c.
At m, it is preferable to contact the developing sleeve 5 in the counter direction with respect to the rotation direction. Instead of the elastic blade 6, it is also possible to use a magnetic doctor blade such as iron.

The primary charging means has been described using the charging roller 2 as a contact charging member.
Contact charging means such as a charging brush may be used. This contact charging member is preferable in that generation of ozone due to charging is small. Although the transfer unit has been described using the transfer roller 9, a contact charging unit such as a transfer blade may be used, and a non-contact corona transfer unit may be used. However, a contact charging unit is preferable because ozone is less generated by transfer.

When the image forming method of the present invention is applied to a facsimile printer, the light image exposure L is an exposure for printing received data. FIG. 3 is a block diagram showing an example of this case.

The controller 31 controls the image reading section 30 and the printer 39. The whole controller 31 is CP
It is controlled by U37. The read data from the image reading unit is transmitted to the partner station through the transmission circuit 33. Data received from the partner station is sent to the printer 39 through the receiving circuit 32. Predetermined image data is stored in the image memory. The printer controller 38 is the printer 3
9 is controlled. 34 is a telephone.

The image received from the line 35 (image information from the remote terminal connected via the line) is demodulated by the receiving circuit 32, and then the CPU 37 performs a decoding process on the image information, and sequentially executes the image memory 36 Is stored in Then, when the image of at least one page is stored in the memory 36,
The image of the page is recorded. The CPU 37 is a memory 3
6, one page of image information is read out and the combined one page of image information is sent to the printer controller 38. The printer controller 38 receives 1
When the image information of the page is received, the printer 39 is controlled to record the image information of the page.

The CPU 37 is receiving the next page during recording by the printer 39.

As described above, image reception and recording are performed.

[0129]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to the following Examples. In addition, “parts” means parts by weight.

<Example 1> [I] Electrostatic image carrier (hereinafter referred to as "photosensitive drum")
Preparation: A 30φ, 254 mm aluminum cylinder was used as a support, and a coating solution composed of the following material was applied on the aluminum cylinder by a dipping method, and thermally cured at 140 ° C. for 30 minutes to form a 15 μm-thick conductive film. A layer was formed. Conductive pigment (SnO ₂ coating process of barium sulfate) 10 parts resistance adjusting pigment (titanium oxide) 2 parts Binder resin (phenol resin) 6 parts Leveling material (silicone oil) 0.001 parts Solvent 20 parts ( Methanol / methoxypropanol; 0.2 / 0.8 [weight ratio])

Next, 3 parts of N-methoxymethylated nylon and 3 parts of copolymerized nylon were added to 65 parts of methanol /
A solution dissolved in a mixed solvent of 30 parts of n-butanol is applied by a dipping method, and dried to have a thickness of 0.5 μm.
Was formed.

Next, in the X-ray diffraction spectrum of CuKα, the diffraction angles 2θ ± 0.2 ° were 9.0 °, 14.2 °, 2 °
4 parts of oxytitanium phthalocyanine (TiOPc) having strong peaks at 3.9 ° and 27.1 °, 2 parts of polyvinyl butyral (trade name: Eslec BM2, manufactured by Sekisui Chemical) and 60 parts of cyclohexanone were used for φ1 mm glass beads. The mixture was dispersed for 4 hours using a sand mill. Thereafter, 100 parts of ethyl acetate was added to prepare a charge generation layer dispersion. This was applied by dipping and dried to form a charge generating layer having a thickness of 0.3 μm on the intermediate layer.

Next, 10 parts of tetrafluoroethylene resin particles (Lubron L-2, manufactured by Daikin) and Condition No. 1 in Table 10 were used. 1
10 parts of the resin described above and 0.07 part of a fluorine-based comb-type graft polymer (GF300, manufactured by Toa Kasei) were sufficiently mixed with 60 parts of monochlorobenzene, and then dispersed with a high-pressure dispersing machine, followed by dispersion with ethylene tetrafluoride resin particles. A dispersion was prepared. When the primary particle size of the tetrafluoroethylene resin particles at this time was measured by a particle size distribution measuring device (manufactured by Horiba, Ltd.), the particle size was 0.25 μm.

Next, 9 parts of an amine compound represented by the following formula:

[0135]

Embedded image 1 part of an amine compound represented by the following formula:

[0136]

Embedded image Condition No. of Table 10 The binder resin 10 described in 1 and 5 parts of the above-mentioned tetrafluoroethylene resin particle dispersion were dissolved in a mixed solvent of 50 parts of monochlorobenzene / 50 parts of dichloromethane. The weight average molecular weight of this resin was 35,000.

This coating solution was applied by a dipping method,
For 2 hours to form a charge transport layer having a thickness of 25 μm on the charge generation layer.

[II] Preparation of toner: 100 parts of binder resin (styrene-based resin) 100 parts of magnetic substance (Fe ₃ O ₄ ) 2 parts of charge control agent (monoazo iron complex) 2 wax (polymer alcohol-based) Wax) 5 parts

The above mixture was melt-kneaded with a twin-screw extruder heated to 130 ° C., and the cooled kneaded material was coarsely pulverized by a hammer mill, and the coarsely pulverized material was finely pulverized by a jet mill. Thus, toner particles having a desired particle size distribution were obtained.

100 parts of the toner particles and 1.5 parts of hydrophobic silica (silicon dioxide) fine powder surface-treated with a silane coupling agent having a number average particle size of 0.02 μm of primary particles and a number average particle size of primary particles Then, 0.3 part of strontium titanate fine powder of 1.80 μm was added and mixed with a Henschel mixer to obtain a toner. The toner has a particle size of 5.80 μm in weight average particle size and 2.00 to 3.1 in particle size.
The content of 7 μm particles was 13% by number.

As the image forming apparatus shown in FIG. 1 in which the process cartridge shown in FIG. 2 is mounted, an LBP “LJ-5L” manufactured by Hewlett-Packard Company is used.
L ”to the process cartridge.
The photosensitive drum prepared in [I] and the above toner were set, and evaluated according to the following image evaluation method.

In the case of "LJ-5L", a contact charging roller which is in contact with the surface of the photoreceptor is used as a primary charging member. DC voltage: -625 V, AC voltage: peak-to-peak voltage 1.8 kV, frequency The image forming apparatus has a configuration in which a charging voltage of 370 Hz is applied to primary charge the photosensitive member.

(A) High temperature and high humidity environment (33.0 ° C., 95
% RH) Drum fusion Image area ratio Approximately 3% After continuous printing of 2500 images, a solid black image is formed on the entire surface of A4 size recording paper, and the degree of white spots generated on the solid black image Was evaluated. A: No white spot is generated on A4 size recording paper. C: About 10 white spots are observed on A4 size recording paper. E: 100 or more white spots are observed on A4 size recording paper.

Note that B is an intermediate level between A and C, and D is an intermediate level between C and E.

Image Deletion An image with an image area ratio of about 3% was continuously printed out on 2500 sheets, and evaluated by the degree of image deletion after 2500 sheets. In this evaluation, experience has shown that paper (33.0 ° C., 95%
The sheet having a moisture absorption of 10% under RH) was used as an evaluation sheet.
In addition, the amount of moisture absorption of the paper is measured by Infrared Engineer.
The measurement was performed using MOISTREX MX 5000 manufactured by Ring. A: No image deletion occurs. C: Image deletion has occurred, but what character is can be determined. E: Image deletion occurs, and it is not possible to determine what characters are.

B is an intermediate level between A and C, and D is an intermediate level between C and E.

(B) Low temperature / low humidity environment (15 ° C., 10% R)
Evaluation in H): White streaks An image with an image area ratio of about 3% was continuously printed out on 2500 sheets, and the level of white streaks was evaluated using a halftone image (1 dot / 2 spaces in the sub-scanning direction) after 2500 sheets. A: No white streaks are generated. C: White streaks are generated but cannot be clearly recognized with the naked eye. E: The occurrence of white streaks can be clearly recognized with the naked eye.

Note that B is an intermediate level between A and C, and D is an intermediate level between C and E.

<Example 2> As the resin of the charge transport layer, the condition No. 1 shown in Table 10 was used. No. 2 resin (6 parts (60% by weight of the whole resin)). A photosensitive drum was produced in the same manner as in Example 1, except that the amount of the resin No. 4 was changed to 4 parts (40% by weight of the whole resin). Image evaluation was performed using the same developer as in Example 1. Table 11 shows the results.

Example 3 As the resin for the charge transport layer, the conditions No. 4 parts (40% by weight of the whole resin) of the resin of Condition No. 3 A photosensitive drum was produced in the same manner as in Example 1, except that 6 parts of the resin No. 5 (60% by weight of the whole resin) was used. The toner has a weight average diameter of 6.8 μm, a particle size of 2.00 to 3.17 μm, and a content of 3% by number.
Image evaluation was performed using 1.2 parts added to 00 parts. Table 11 shows the results.

Example 4 A photosensitive drum was manufactured in the same manner as in Example 1 except that the same resin as in Example 3 was used as the resin for the charge transport layer. With respect to the toner, an image was evaluated using the same toner as used in Example 1. Table 11 shows the results.

<Example 5> In the production of the photosensitive drum, up to the charge generation layer was formed in the same manner as in Example 1.

As the charge transport layer forming step, 10 parts of tetrafluoroethylene resin particles (Lubron L-2, manufactured by Daikin) and Condition No. 10 in Table 10 were used. After thoroughly mixing 10 parts of the resin No. 1 and 0.04 part of a fluorine-based comb-type graft polymer (GF300, manufactured by Toa Kasei) with 60 parts of monochlorobenzene, the mixture is dispersed by a high-pressure dispersing machine and dispersed into tetrafluoroethylene resin particles. A dispersion was prepared. When the primary particle size of the tetrafluoroethylene resin particles at this time was measured by a particle size distribution measuring device (manufactured by Horiba, Ltd.), the particle size was 0.18 μm.

Next, 9 parts of an amine compound represented by the following formula:

[0155]

Embedded image 1 part of an amine compound represented by the following formula:

[0156]

Embedded image 10 parts of the resin used in Example 3, 15 parts of the above-mentioned tetrafluoroethylene resin particle dispersion, and 0.2 part of a hindered phenolic antioxidant represented by the following formula

[0157]

Embedded image And 0.2 parts of a phosphorus-based antioxidant represented by the following formula:

[0158]

Embedded image A photoconductor drum was prepared in the same manner as in Example 3, except that was used. Image evaluation was performed in the same manner as in Example 1 using the above-described photosensitive drum and the toner used in Example 1. Table 11 shows the results.

<Example 6> In preparing the toner, 20 parts per 100 parts of the silica fine powder treated with the silane coupling agent was used instead of the silica fine powder surface-treated with the silane coupling agent used in Example 1. The image was evaluated in the same manner as in Example 5, except that the silicone oil (viscosity: 100 cSt) was used. Table 11 shows the results.

<Example 7> In the preparation of the toner in Example 5, instead of using strontium titanate fine powder, titanium oxide fine powder (number average particle diameter of primary particles: 0.1.
The image evaluation was performed in the same manner as in Example 5 except that 18 μm) was used. Table 11 shows the results.

<Comparative Example 1> In the preparation of the photosensitive drum, no tetrafluoroethylene resin particles were used. A photosensitive drum was prepared in the same manner as in Example 3 except that the charge transport layer was formed using only 10 parts of the resin No. 5, and image evaluation was performed in the same manner as in Example 3. Table 11 shows the results.

<Comparative Example 2> In the preparation of the photosensitive drum, no tetrafluoroethylene resin particles were used, and the condition Nos. A photosensitive drum was prepared in the same manner as in Example 3 except that the charge transport layer was formed using only 10 parts of the resin No. 3, and image evaluation was performed in the same manner as in Example 3. Table 11 shows the results.

Reference Example 1 A toner was prepared in the same manner as in Example 1 except that the strontium titanate fine powder used in the toner used in Example 1 was not used. Image evaluation. Table 11 shows the results.

<Reference Example 2> In place of the strontium titanate fine powder used in the toner used in Example 1, a strontium titanate fine powder having a number average particle size of primary particles of 3.5 μm was used. A toner was prepared in the same manner as in Example 1, and image evaluation was performed in the same manner as in Example 1. Table 11 shows the results.

<Reference Example 3> Except for using strontium titanate fine powder having a primary particle number average particle size of 0.09 µm in place of the strontium titanate fine powder used in the toner used in Example 1, A toner was prepared in the same manner as in Example 1, and image evaluation was performed in the same manner as in Example 1. Table 11 shows the results.

[0166]

[Table 10]

[0167]

[Table 11]

[0168]

According to the present invention, by using a toner having a specific electrostatic image carrier and a specific inorganic fine powder, image transfer does not occur even if any transfer material is used under high temperature and high humidity. In this environment, it is possible to provide an image forming method that does not cause drum fusion or drum white stripes.

[Brief description of the drawings]

FIG. 1 is a view schematically showing an example of an image forming apparatus used in an image forming method of the present invention.

FIG. 2 is an explanatory view showing one embodiment of a process cartridge of the present invention.

FIG. 3 is a block diagram when the image forming method of the present invention is applied to a facsimile printer.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electrostatic image carrier 2 primary charging device 3 exposure optical system 4 developing device 5 toner carrier 6 toner layer thickness regulating member 7 toner stirring means 8 developing bias power supply 9 transfer device 10 transfer current generator 11 cleaning means 12 fixing device 13 Toner P Transfer material (recording material)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/02 102 G03G 9/08 374 15/08 507 375 375 15/08 507L

Claims (18)

[Claims] An electrostatic image carrier for carrying an electrostatic image is charged, an electrostatic image is formed on the charged electrostatic image carrier, and the electrostatic image is developed by a toner included in a developing unit. A toner image on a transfer material with or without an intermediate transfer member, and fixing the toner image on the transfer material by a fixing unit. The electrostatic image carrier has a surface layer of 7.5 × 10 ^3.
Formula (1) having a weight average molecular weight of ~ 3.7 × 10 ⁴ Wherein, X ₁ is -CR ₁₃ R ₁₄ - (provided that R ₁₃ and R ₁₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{1 to} R ₁₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Or a polyarylate resin having a structural unit represented by the formula:
Formula (2) having a weight average molecular weight of ^{3 to} 3.7 × 10 ⁴ [Wherein, X ₂ is -CR ₂₃ R _24- (where R ₂₃ and R ₂₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{15 to} R ₂₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. ] The toner contains at least one kind of polycarbonate resin having a structural unit represented by the following formula (1) and fluorine-based resin particles.
m and the first inorganic fine powder having a number average particle size of 0.12 or less.
An image forming method comprising: a second inorganic fine powder having a particle diameter of 2 to 3.0 μm. 2. The first inorganic fine powder is a silica fine powder, which is contained in the toner in an amount of 0.5 to 2.5% by weight.
2. The image forming method according to claim 1, wherein the inorganic fine powder is titanium oxide, strontium titanate or cerium oxide, and is contained in the toner in an amount of 0.35 to 3.5% by weight. 3. The image forming method according to claim 1, wherein the first inorganic fine powder contains 3 to 20% by weight of silicone oil. 4. The toner according to claim 1, wherein the weight average particle diameter is 3.5 to 6.5 μm, and the content of particles having a particle diameter of 2.00 to 3.17 μm is 5 to 40% by number. The image forming method according to claim 1. 5. The method according to claim 1, wherein the surface layer of the electrostatic image carrier contains at least one of a hindered phenol-based antioxidant and a phosphorus-based antioxidant. Image forming method. 6. The electrostatic image carrier is charged by applying a voltage obtained by superimposing an AC voltage on a DC voltage from a charging member in contact with the electrostatic image carrier. 6. The image forming method according to any one of 1 to 5. 7. A process cartridge detachably mounted on an image forming apparatus main body, wherein the process cartridge is provided with an electrostatic image carrier for carrying an electrostatic image, and is carried on the electrostatic image carrier. Developing means for holding a toner for developing an electrostatic image to form a toner image, wherein the electrostatic image carrier has a surface layer of 7.5 × 10 ³
Formula (1) having a weight average molecular weight of ~ 3.7 × 10 ⁴ Wherein, X ₁ is -CR ₁₃ R ₁₄ - (provided that R ₁₃ and R ₁₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{1 to} R ₁₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Or a polyarylate resin having a structural unit represented by the formula:
Formula (2) having a weight average molecular weight of ^{3 to} 3.7 × 10 ⁴ [Wherein, X ₂ is -CR ₂₃ R _24- (where R ₂₃ and R ₂₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{15 to} R ₂₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. ] The toner contains at least one kind of polycarbonate resin having a structural unit represented by the following formula (1) and fluorine-based resin particles.
m and the first inorganic fine powder having a number average particle size of 0.12 or less.
A second inorganic fine powder having a thickness of from 3.0 to 3.0 μm. 8. The first inorganic fine powder is a silica fine powder, which is contained in the toner in an amount of 0.5 to 2.5% by weight.
8. The process cartridge according to claim 7, wherein the inorganic fine powder is titanium oxide, strontium titanate or cerium oxide, and is contained in the toner in an amount of 0.35 to 3.5% by weight. 9. The process cartridge according to claim 7, wherein the first inorganic fine powder contains 3 to 20% by weight of silicone oil. 10. The toner has a weight average particle diameter of 3.5 to 6.5 μm and a content of particles having a particle diameter of 2.00 to 3.17 μm or less of 5 to 40% by number. The process cartridge according to any one of claims 7 to 9, wherein 11. The surface layer of the electrostatic charge image bearing member contains at least one of a hindered phenol antioxidant and a phosphorus antioxidant.
11. The process cartridge according to any one of claims 10 to 10. 12. The process cartridge according to claim 1, further comprising a charging member which is arranged in contact with said electrostatic image carrier and applies a voltage obtained by superimposing a DC voltage and an AC voltage. 12. The process cartridge according to any one of 7 to 11. 13. The following formula (1) having a weight average molecular weight of 7.5 × 10 ^{3 to} 3.7 × 10 ^4. Wherein, X ₁ is -CR ₁₃ R ₁₄ - (provided that R ₁₃ and R ₁₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{1 to} R ₁₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Or a polyarylate resin having a structural unit represented by the formula:
Formula (2) having a weight average molecular weight of ^{3 to} 3.7 × 10 ⁴ [Wherein, X ₂ is -CR ₂₃ R _24- (where R ₂₃ and R ₂₄
Is each independently a hydrogen atom, a trifluoromethyl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), a substituted or unsubstituted cycloalkylidene group, a substituted or unsubstituted α, ω- Alkylene group, single bond, -O-, -S-, -SO-, or -S
O ₂ —, and R _{15 to} R ₂₂ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. The electrostatic image carrier having a surface layer containing at least one kind of polycarbonate resin having the structural unit represented by formula (1) and fluorine-based resin particles to form an electrostatic image on the charged electrostatic image carrier. Developing the electrostatic image with the toner of the developing unit to form a toner image, transferring the toner image on the electrostatic image carrier to a transfer material with or without an intermediate transfer member, An image forming toner used in an image forming method in which a toner image is fixed by a fixing unit, wherein the toner has toner particles and a number average particle diameter of 0.10 μm.
m and the first inorganic fine powder having a number average particle size of 0.12 or less.
And a second inorganic fine powder having a particle size of from 3.0 to 3.0 μm. 14. The first inorganic fine powder is a silica fine powder, which is contained in the toner in an amount of 0.5 to 2.5% by weight, and the second inorganic fine powder is titanium oxide, strontium titanate. Or cerium oxide, which is contained in the toner in an amount of 0.35 to 3.5% by weight.
4. The toner for forming an image according to claim 1. 15. The first inorganic fine powder is 3 to 20% by weight.
The image forming toner according to claim 13, further comprising a silicone oil. 16. The toner according to claim 1, wherein the weight average particle diameter is 3.5 to 6.5 μm, and the content of particles having a particle diameter of 2.00 to 3.17 μm is 5 to 40% by number. The image forming toner according to claim 13. 17. The method according to claim 17, wherein the surface layer of the electrostatic image carrier used in the image forming method using the toner contains at least one of a hindered phenol antioxidant and a phosphorus antioxidant. The image forming toner according to claim 13. 18. An image forming method using the toner, wherein a voltage obtained by superimposing an AC voltage on a DC voltage is applied from a charging member in contact with the electrostatic image carrier to thereby apply the electrostatic image carrier. 18. The image forming toner according to claim 13, wherein the toner is charged.