JP5303841B2 - Electrostatic image developing toner, electrostatic image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner having excellent low temperature fixability, and capable of obtaining fixability stable to a change in toner application quantity in a toner image, to provide an electrostatic charge image developer, to provide a toner cartridge, to provide a process cartridge, and to provide an image forming apparatus. <P>SOLUTION: The electrostatic charge image developing toner comprises: a noncrystalline polyester resin; a crystalline polyester resin; a releasing agent; and a coloring agent. The content of the crystalline polyester resin lies in the range of 5 to 15 mass% to the whole of the toner, and, when the soluble content of tetrahydrofuran is dript into methanol, the amount of the dissolved component to the methanol is &le;1 mass% to the whole of the toner. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

The present invention relates to an electrostatic charge image developing toner, an electrostatic charge image developer, a toner cartridge, a process cartridge, an image forming apparatus, and an image forming method .

  A method of visualizing image information through an electrostatic latent image, such as electrophotography, is currently widely used in various fields. In the electrophotographic method, an electrostatic latent image on the surface of an electrophotographic photoreceptor (image carrier, hereinafter sometimes referred to simply as “photoreceptor”) is subjected to an electrostatic charge image developing toner (charge toner, exposure process, etc.). The electrostatic latent image is visualized through a transfer process, a fixing process, and the like.

  In recent years, from the viewpoint of energy saving, which is particularly demanding, improvement of a fixing process that consumes a large amount of energy is generally performed in a heat melting method in which toner is melted and fixed by heat. For example, by lowering the fixing temperature, it is possible to shorten the start-up time after power input, extend the life of the fixing roll member, and increase the process speed. Therefore, it is desired that the toner is melted at a lower temperature and fixed on paper.

  As the toner that can be fixed at a low temperature, a method using a crystalline polyester that melts sharply at a low temperature has been studied (for example, see Patent Document 1). In addition, in order to improve low-temperature fixability and hot offset resistance, a method in which a crystalline polyester resin and an amorphous polyester resin are mixed (for example, see Patent Document 2), or a crystalline polyester resin is converted into an amorphous polyester resin. Improvement of low-temperature fixability and chargeability is achieved by a method of coating with (for example, see Patent Document 3).

On the other hand, in order to avoid toner aggregation and poor charging in a high temperature environment, toners that define the amount of a soluble resin component extracted with methanol are known (see, for example, Patent Documents 4 and 5). Has improved the cohesiveness of the toner surface by controlling the amount of the methanol-soluble resin component present in the vicinity of the toner surface through which methanol can permeate.
JP 49-12950 A JP 2002-318471 A JP 2004-191927 A Japanese Patent No. 3720651 Japanese Patent No. 3754848

An object of the present invention is to provide an electrostatic charge image developing toner, an electrostatic charge image developer, a toner cartridge, a process cartridge, which are excellent in low-temperature fixability and can obtain stable fixability with respect to a change in the amount of applied toner in a toner image. An image forming apparatus and an image forming method are provided.

The above-mentioned subject is achieved by the following present invention.
That is, the invention according to claim 1 of the present invention is

Amorphous polyester resin obtained from polycondensation of polyvalent aromatic carboxylic acid and polyhydric alcohol having bisphenol skeleton, Crystallinity obtained from polycondensation of polyhydric aliphatic carboxylic acid and polyhydric aliphatic alcohol Comprising polyester resin, mold release agent and colorant,
The content of the crystalline polyester resin is in the range of 5 to 15% by mass of the whole toner,
Add 100 g of tetrahydrofuran to 20 g of toner , heat and stir to 40 ° C., hold for 30 minutes, cool to room temperature, heat and filter with a glass filter, and stir methanol in a container containing 300 g of methanol. The filtrate was added dropwise over 10 minutes, and stirring was continued for 30 minutes after the addition. The filtrate was filtered, and the filtrate was desolvated, dried and weighed, and the mass was determined by dividing the mass by the original toner mass. The amount of the component dissolved in methanol is 1% by mass or less based on the whole toner,
100 g of tetrahydrofuran was added to 20 g of the amorphous polyester resin , heated and stirred at 40 ° C., held for 30 minutes, cooled to room temperature, filtered by heating with a glass filter, and put into a container containing 300 g of methanol. While stirring the filtrate, the filtrate was added dropwise over 10 minutes. After the addition, stirring was continued for 30 minutes, this was filtered, the filtrate was desolvated, dried and weighed, and the mass was determined based on the amorphous polyester resin. The amount of the component dissolved in methanol determined by dividing by the mass of the non-crystalline polyester resin is 1% by mass or less,
Add 100 g of tetrahydrofuran to 20 g of the crystalline polyester resin , heat and stir at 40 ° C., hold for 30 minutes, cool to room temperature, heat and filter with a glass filter, and put methanol in a container containing 300 g of methanol. While stirring, the filtrate was added dropwise over 10 minutes. After the addition, stirring was continued for 30 minutes, this was filtered, the filtrate was desolvated, dried and weighed, and the mass was the mass of the original crystalline polyester resin. The amount of the component dissolved in methanol determined by dividing by is 1% by mass or less based on the entire crystalline polyester resin,
And it is obtained by emulsifying and aggregating these resins.

According to a second aspect of the present invention, there is provided an electrostatic charge in which each dispersion of the amorphous polyester resin and the crystalline polyester resin used for emulsion aggregation in the electrostatic charge image developing toner according to the first aspect includes an acid, a salt or a base. This is an image developing toner.

The invention according to claim 3 is the electrostatic charge image development in which the release agent in the toner for electrostatic charge image development according to claim 1 or 2 is at least one selected from paraffin wax, carnauba wax and ester wax. Toner.

The invention according to claim 4 is an electrostatic charge image developer containing toner, wherein the toner is the electrostatic charge image developing toner according to any one of claims 1 to 3 .

The invention according to claim 5 is a toner cartridge that contains at least toner, and the toner is the electrostatic image developing toner according to any one of claims 1 to 3 .

According to a sixth aspect of the present invention, there is provided a process cartridge comprising at least a developer holder and containing the electrostatic charge image developer according to the fourth aspect .

According to a seventh aspect of the present invention, there is provided an image carrier, a developing unit that develops an electrostatic image formed on the image carrier as a toner image with a developer, and a toner image formed on the image carrier. An image forming apparatus comprising: a transfer unit that transfers onto a transfer body; and a fixing unit that fixes a toner image transferred onto the transfer body, wherein the developer is the electrostatic charge image developer according to claim 4. Device.
According to an eighth aspect of the present invention, a developing process for developing an electrostatic charge image formed on an image carrier as a toner image with a developer, and a toner image formed on the image carrier is transferred onto a transfer target. An image forming method comprising: a transfer step; and a fixing step of fixing a toner image transferred onto a transfer target, wherein the developer is the electrostatic charge image developer according to claim 4. .

According to the first aspect of the present invention, it is possible to obtain a toner that has excellent fixability in a low temperature fixability, can control the temperature at which hot offset occurs, and has a wide fixable temperature range.
According to the first aspect of the invention, it is possible to control the temperature at which hot offset occurs and to obtain a toner having excellent fixability with a wide fixable temperature range.
According to the second aspect of the present invention, when the toner is produced by the emulsion aggregation method, the particle size of the emulsified particles can be controlled, and the particle size distribution of the toner can be kept stable. In addition, the temperature at which hot offset occurs can be controlled, and a toner having excellent fixability with a wide fixable temperature range can be obtained.
According to the third aspect of the present invention, the release agent is more likely to ooze out during fixing, and offset resistance can be improved.
According to the fourth aspect of the present invention, it is possible to provide an electrostatic charge image developer that is excellent in low-temperature fixability, can control the temperature at which hot offset occurs, and has excellent fixability over a wide fixable temperature range.
According to the invention of claim 5 , it is excellent in low-temperature fixability, can control the temperature at which hot offset occurs, facilitates the supply of toner for developing an electrostatic charge image having excellent fixability in a wide fixable temperature range, and Maintainability of characteristics can be improved.
According to the invention of claim 6 , it is excellent in low-temperature fixability, can control the temperature at which hot offset is generated, facilitates handling of an electrostatic charge image developer having a wide fixable temperature range and excellent fixability, The adaptability of the configuration to the image forming apparatus can be improved.
According to the seventh aspect of the present invention, it is excellent in low-temperature fixability, the temperature at which hot offset is generated can be controlled, and image formation having excellent fixability in a wide fixable temperature range can be maintained.
According to the eighth aspect of the present invention, it is excellent in low-temperature fixability, the temperature at which hot offset is generated can be controlled, and image formation having excellent fixability in a wide fixable temperature range can be maintained.

Hereinafter, the present invention will be described in detail.
<Toner for electrostatic image development>
The toner for developing an electrostatic charge image of the present invention comprises an amorphous polyester resin, a crystalline polyester resin, a release agent and a colorant, and the content of the crystalline polyester resin is 5 to 15 mass of the whole toner. %, And when the tetrahydrofuran soluble part of the toner is dropped into methanol, the amount dissolved in the methanol is 1% by mass or less based on the whole toner.
However, the amorphous polyester resin is an amorphous polyester resin obtained by condensation polymerization of a polyvalent aromatic carboxylic acid and a polyhydric alcohol having a bisphenol skeleton.
As the crystalline polyester resin, a crystalline polyester resin obtained by condensation polymerization of a polyvalent aliphatic carboxylic acid and a polyvalent aliphatic alcohol is used.
When the tetrahydrofuran-soluble content of the toner is dropped into methanol, the amount dissolved in the methanol is determined by adding the tetrahydrofuran-soluble content of the toner that has been filtered by adding the toner to tetrahydrofuran. This is the amount of components dissolved in methanol when it is dropped into methanol so that the mass ratio is 3: 1.
A filtrate containing tetrahydrofuran-soluble components of the amorphous polyester resin filtered in addition to tetrahydrofuran to the amorphous polyester resin was dropped into methanol so that the tetrahydrofuran and methanol were in a mass ratio of 3: 1. When the amount of the component dissolved in methanol is 1% by mass or less with respect to the entire amorphous polyester resin,
A filtrate containing the tetrahydrofuran-soluble content of the crystalline polyester resin filtered in addition to tetrahydrofuran to the crystalline polyester resin was dropped into methanol so that the tetrahydrofuran and methanol were in a mass ratio of 3: 1. The amount of the component dissolved in methanol at that time is 1% by mass or less with respect to the entire crystalline polyester resin.
A toner obtained by emulsifying and aggregating these resins is applied.

  The toner of the present invention contains a crystalline polyester resin as a binder resin for the low-temperature fixing. In this case, offset resistance may be a problem because the melt viscosity suddenly decreases due to heating during fixing. In particular, there is a problem that offset is likely to occur in a halftone image or a dot image in which the toner application amount (toner amount per unit area on the recording medium) is small in the toner image, and the fixability varies even at the same fixing temperature depending on the toner application amount. It was.

  The present inventors examined the occurrence of the offset by paying attention to the amount of low molecular weight components in the binder resin. The amount of low molecular weight components in the toner can be grasped to some extent by the amount of soluble resin components extracted with methanol as described above. However, as a result of studies by the present inventors, in the case of a toner containing a crystalline polyester resin as a binder resin component, even if the amount of the methanol-soluble resin component obtained by the conventional method is controlled, the offset resistance in the toner is reduced. It was found that a clear correlation with sex could not be obtained.

  The reason for this is that the amount of soluble resin components extracted with methanol in the conventional method reflects the amount of low molecular weight resin components existing near the surface of the toner, and offset when the entire toner melts during fixing. It is thought that it does not correspond to an ingredient. Therefore, for a toner containing a crystalline polyester resin, the toner is dissolved in tetrahydrofuran (THF), and when the soluble component at this time is further dropped into methanol, the amount of dissolved components in methanol is used as a new index. When the relationship with the occurrence of offset was confirmed, it was found that a good correlation was obtained.

Specifically, the amount of components dissolved in methanol obtained by the above measurement method is 1% by mass or less with respect to the whole toner, so that even in the case of an image with a low amount of applied toner such as a halftone image, it is resistant to offset. As a result, it was found that fixing performance comparable to that of a solid image having a high toner loading was obtained.
This is because the amount of low molecular weight components inside the toner that affect offset resistance when the toner is melted is determined by making the soluble part of the toner dissolved in THF, and the dissolved component is extracted by dropping it into methanol. By doing so, it seems that a low molecular weight component amount in a state where the molecular chain constituting the resin corresponding to the melting is expanded is obtained.

  By reducing the amount of the component dissolved in methanol to 1% by mass or less, the crystallinity of the crystalline polyester resin is increased and melts sharper at the time of fixing, and the amorphous polyester resin, the release agent and the crystalline polyester are used. Since the resin is less compatible with each other and the crystalline polyester resin and the release agent are easily separated, the crystalline polyester resin and the release agent are rapidly melted onto the toner surface when the toner is melted. Then, the release agent itself melts out more quickly, and the release agent is pushed out by the melt-out of the crystalline polyester resin, thereby further promoting the seepage of the release agent onto the toner surface. Therefore, it is considered that the offset resistance during fixing is improved.

In particular, in low-temperature fixing (low-temperature fixing means fixing by heating the toner at about 150 ° C. or less), offset of a halftone image with a small amount of toner in the image tends to occur. The applied amount dependency is improved, and an offset hardly occurs even in a halftone image.
The amount of the dissolved component is desirably 1.0% by mass or less, and more desirably 0.85% by mass or less. Ideally, it is 0% by mass. The method for measuring the amount of the dissolved component will be described later.

In the toner of the present invention, the content of the crystalline polyester resin is in the range of 5 to 15% by mass. By setting the content of the crystalline polyester resin within this range, low-temperature fixability can be secured and exposure to the surface of the crystalline polyester resin during toner granulation is reduced, resulting in a difference in charge amount generated between toner particles. The resulting fogging and storage can be improved.
The content is desirably in the range of 5 to 15% by mass, and more desirably in the range of 8 to 13% by mass.

Hereinafter, the present invention will be described by way of embodiments.
(Crystalline polyester resin)
In the present invention, the “crystalline polyester resin” refers to a resin having a clear endothermic peak instead of a stepwise endothermic amount change in differential scanning calorimetry (DSC) as described above, and a resin having the endothermic peak. As long as it is a polymer obtained by copolymerizing other components with respect to the crystalline polyester main chain, this copolymer is also a crystalline polyester resin if the other components are 50 constituent mol% or less. That is, a crystalline polyester resin is obtained by showing an endothermic peak. Hereinafter, although the preferable example of crystalline polyester resin is shown, it is not limited to what is shown here.

The crystalline polyester resin used in this embodiment is desirably synthesized from a polyvalent carboxylic acid component and a polyhydric alcohol component. In addition, a commercial item may be used as said crystalline polyester resin, and what was synthesize | combined suitably may be used.
Examples of the polyvalent carboxylic acid component include oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1, Aliphatic dicarboxylic acids such as 12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, mesaconine Aromatic dicarboxylic acids such as dibasic acids such as acids; and the like, and anhydrides and lower alkyl esters thereof are also included, but not limited thereto.
Examples of trivalent or higher carboxylic acids include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, and anhydrides thereof. And lower alkyl esters. These may be used individually by 1 type and may use 2 or more types together.

Moreover, as an acid component, the dicarboxylic acid component which has a sulfonic acid group other than the above-mentioned aliphatic dicarboxylic acid and aromatic dicarboxylic acid may be contained. Examples of the dicarboxylic acid having a sulfone group include, but are not limited to, 2-sulfoterephthalic acid sodium salt, 5-sulfoisophthalic acid sodium salt, and sulfosuccinic acid sodium salt. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned.
The divalent or higher carboxylic acid component having a sulfonic acid group is desirably contained in the range of 0 to 20 mol%, more preferably 0 to 10 mol%, based on all carboxylic acid components constituting the polyester. Range. When the content is more than 20 mol%, for example, not only the crystallinity of the crystalline polyester resin is lowered, but also the process of coalescence after aggregation is adversely affected during granulation, making it difficult to adjust the toner diameter. There may be a problem that it becomes.

  As the polyhydric alcohol component, an aliphatic diol is desirable, and a linear aliphatic diol having 6 to 20 carbon atoms in the main chain portion is more preferable. When the aliphatic diol is branched, for example, the crystallinity of the crystalline polyester resin is lowered and the melting point is lowered, so that toner blocking resistance, image storage stability, and low-temperature fixability are deteriorated. There is. Further, if the number of carbon atoms is less than 6, when the polycondensation with an aromatic dicarboxylic acid is performed, the melting point becomes high and fixing at a low temperature may be difficult. On the other hand, if it exceeds 20, it is difficult to obtain a practical material. There is a case. The carbon number is more preferably 14 or less.

  In the present embodiment, examples of the aliphatic diol suitably used for the synthesis of the crystalline polyester resin include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1, 6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13 -Tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosandecanediol and the like are exemplified, but not limited thereto. Among these, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferable in view of availability.

Examples of trihydric or higher alcohols include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. These may be used individually by 1 type and may use 2 or more types together.
If necessary, monovalent acids such as acetic acid and benzoic acid, and monovalent alcohols such as cyclohexanol benzyl alcohol can also be used for the purpose of adjusting the acid value and the hydroxyl value.

The method for producing the crystalline polyester resin is not particularly limited, and can be produced by a general polyester polymerization method in which an acid component and an alcohol component are reacted. Examples thereof include direct polycondensation and transesterification. They are manufactured using different types of monomers.
The production of the crystalline polyester resin can be carried out at a polymerization temperature of 180 to 230 ° C., and the reaction is carried out while reducing the pressure in the reaction system as necessary to remove water and alcohol generated during condensation. When the monomer is not dissolved or compatible at the reaction temperature, a solvent having a high boiling point may be added as a solubilizer and dissolved. In the polycondensation reaction, the dissolution auxiliary solvent is distilled off. In the case where a monomer having poor compatibility exists in the copolymerization reaction, it is preferable that the monomer having poor compatibility and the monomer and the acid or alcohol to be polycondensed are condensed in advance and then polycondensed together with the main component.

Catalysts that can be used in the production of the crystalline polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; zinc, manganese, antimony, titanium, tin, zirconium, germanium, aluminum, etc. Metal compounds; phosphorous acid compounds, phosphoric acid compounds, amine compounds, and the like. Specific examples include the following compounds.
Specifically, for example, sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, zinc acetate, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate, titanium Tetraethoxide, titanium tetrapropoxide, titanium tetraisoproxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium Tetrabutoxide, zirconium naphthenate, zirconyl carbonate, zirconyl acetate, zirconyl stearate, zirconyl octylate, germanium oxide, Aluminum, triphenyl phosphite, tris (2, 4-t-butylphenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, compounds such as triphenyl amine. From the viewpoint of reactivity, antimony, tin, and titanium are desirable. From the viewpoint of environmental impact and safety, titanium is more desirable.

As melting | fusing point of crystalline polyester resin, Preferably it is the range of 50-100 degreeC, More preferably, it is the range of 60-80 degreeC. When the melting point is lower than 50 ° C., the storage stability of the toner and the storage stability of the toner image after fixing may become a problem. On the other hand, when the temperature is higher than 100 ° C., sufficient low-temperature fixing may not be obtained as compared with conventional toners.
In addition, melting | fusing point of the said crystalline polyester resin was calculated | required as the peak temperature of the endothermic peak obtained by the said differential scanning calorimetry (DSC).

  The molecular weight of the crystalline polyester resin can be adjusted depending on the reaction time and the molar ratio of monomers. Although the reaction time varies depending on the type of catalyst and monomer, the molecular weight is small when the reaction time is short, and it is large when the reaction time is long. A high molecular weight product can be obtained by adjusting the molar ratio of the monomer so that the ratio of alcohol to carboxylic acid in the monomer is 1: 1.

  The weight average molecular weight (Mw) immediately after the synthesis of the crystalline polyester resin is preferably in the range of 3000 to 35000, and more preferably in the range of 10,000 to 30000. When the molecular weight (Mw) is less than 3000, offset may be easily generated during fixing, and when the weight average molecular weight (Mw) exceeds 35000, fixability at low temperature may be deteriorated.

In this embodiment, for the production of the toner described later, a crystalline polyester resin having a soluble component amount in methanol of 1% by mass or less when a tetrahydrofuran soluble component is dropped into methanol is used. desirable. If the amount of the soluble component exceeds 1% by mass, the amount of the methanol soluble component when the THF soluble component of the toner is dropped into methanol may not be 1% by mass or less.
The amount of the dissolved component of the crystalline polyester resin is more preferably 0.8% by mass or less.

A method for obtaining a crystalline polyester resin having a small amount of the methanol-soluble component as described above is not particularly limited, and can be obtained, for example, by dissolving the resin in THF and performing reprecipitation purification.
Specifically, first, a crystalline polyester resin is dissolved in THF at a concentration of about 5 to 50% by mass, and this is dropped into stirred methanol having a mass 2 to 10 times that of the solution. . In this case, the dropping time and the stirring time vary depending on the amount of the solution. For example, when the amount of the solution is 100 g, it is desirable that the dropping time is about 5 minutes and the stirring time is about 30 minutes.

  In the purified crystalline polyester resin, the amount of the soluble component in methanol is in the desired range. In this case, the weight average molecular weight (Mw) of the purified crystalline polyester resin is in the range of 3000 to 35000. It is desirable that it is in the range of 15000 to 25000.

  Moreover, it is desirable that the DSC peak temperature of the purified crystalline polyester resin is in the range of 70 to 90 ° C.

  The weight average molecular weight and molecular weight distribution can be measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC was performed with a THF solvent using a Tosoh column / TSKgel Super HM-M (15 cm) using a Tosoh GPC / HLC-8120 as a measuring device. The weight average molecular weight is calculated from the measurement result using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

  The content of the crystalline polyester resin in the toner is in the range of 5 to 15% by mass as described above, but the content of the crystalline polyester resin in the toner is a crystalline polyester using a specific solvent described later. It can be determined by separating the resin and the amorphous polyester resin.

(Amorphous polyester resin)
The “amorphous polyester resin” used in the present invention is a resin in which a stepwise endothermic change is recognized instead of a clear endothermic peak in differential scanning calorimetry (DSC). When an amorphous polyester resin is used, it is advantageous in that a resin particle dispersion described later can be easily prepared by adjusting the acid value of the resin or by emulsifying and dispersing using an ionic surfactant. It is.

The amorphous polyester resin used in the present embodiment is obtained mainly by condensation polymerization of polyvalent carboxylic acids and polyhydric alcohols.
Examples of the polyvalent carboxylic acid include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, and naphthalenedicarboxylic acid; maleic anhydride, fumaric acid, succinic acid, alkenyl anhydride Aliphatic carboxylic acids such as succinic acid and adipic acid; alicyclic carboxylic acids such as cyclohexanedicarboxylic acid; and the like, and one or more of these polyvalent carboxylic acids can be used.
Among these polyvalent carboxylic acids, it is preferable to use aromatic carboxylic acids, and for the purpose of ensuring good fixability, trivalent or higher carboxylic acids (trivalent or higher carboxylic acids) are introduced together with dicarboxylic acids in order to introduce a crosslinked structure or branched structure. It is preferable to use trimellitic acid or its acid anhydride in combination.

Examples of the polyhydric alcohol include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, and glycerin; cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, and the like. Alicyclic diols; aromatic diols such as an ethylene oxide adduct of bisphenol A, a propylene oxide adduct of bisphenol A; and the like, and one or more of these polyhydric alcohols can be used.
Among these polyhydric alcohols, aromatic diols and alicyclic diols are preferable, and aromatic diols are more preferable. For the purpose of ensuring good fixability, a trihydric or higher polyhydric alcohol (glycerin, trimethylolpropane, pentaerythritol) may be used in combination with the diol in order to introduce a crosslinked structure or a branched structure.

A polyester resin obtained by polycondensation of a polyvalent carboxylic acid and a polyhydric alcohol is further added with a monocarboxylic acid and / or monoalcohol to esterify the hydroxyl group and / or carboxyl group at the polymerization terminal, thereby producing a polyester. The acid value of the resin may be adjusted.
Examples of the monocarboxylic acid include acetic acid, acetic anhydride, benzoic acid, trichloroacetic acid, trifluoroacetic acid, and propionic anhydride. Examples of the monoalcohol include methanol, ethanol, propanol, octanol, 2-ethylhexanol, trifluoroethanol, trichloroethanol, hexafluoroisopropanol, and phenol.

  The amorphous polyester resin can be produced by subjecting the polyhydric alcohol and polyhydric carboxylic acid to a condensation reaction according to a conventional method. For example, the polyhydric alcohol and polyhydric carboxylic acid, if necessary, a catalyst is added, blended in a reaction vessel equipped with a thermometer, a stirrer, a flow-down condenser, and in the presence of an inert gas (such as nitrogen gas), Heat at 150 to 250 ° C. to continuously remove by-product low-molecular compounds out of the reaction system, stop the reaction when a predetermined acid value is reached, cool, and obtain the desired reactant Can be manufactured.

  As the catalyst used for the synthesis of the amorphous polyester resin, antimony, tin, titanium, and aluminum catalysts are used. Examples thereof include esterification catalysts such as organic metals such as dibutyltin dilaurate and dibutyltin oxide and metal alkoxides such as tetrabutyl titanate. From the viewpoint of environmental impact and safety, titanium is more desirable. The amount of such a catalyst added is preferably in the range of 0.01 to 1.00% by mass with respect to the total amount of raw materials.

The amorphous polyester resin used in the present embodiment has a weight average molecular weight (Mw) in the range of 5,000 to 100,000 by molecular weight measurement by gel permeation chromatography (GPC) method of the THF-soluble matter. Is more preferable, and a range of 10,000 to 50,000 is more preferable.
If the weight average molecular weight is less than 5000, it is effective for low-temperature fixability, but not only the hot offset resistance is deteriorated, but also the resin strength is lowered, so that the image strength fixed on the paper is lowered. There is a case. On the other hand, if the molecular weight is larger than 100,000, the hot offset resistance can be sufficiently provided, but the low-temperature fixability is deteriorated and the bleeding of the crystalline polyester phase present in the toner is inhibited, so that the document storage stability is adversely affected. May affect. Therefore, by satisfying the above conditions, it becomes easy to achieve both low-temperature fixability, hot offset resistance, and document storage stability.

In this embodiment, for the production of the toner described later, a non-crystalline polyester resin having a soluble component amount in methanol of 1% by mass or less when a tetrahydrofuran soluble component is dropped into methanol is used. It is desirable. If the amount of the soluble component exceeds 1% by mass, the amount of the methanol soluble component when the THF soluble component of the toner is dropped into methanol may not be 1% by mass or less.
The amount of the dissolved component of the amorphous polyester resin is more preferably 5% by mass or less.

The method for obtaining an amorphous polyester resin having a small amount of methanol-soluble components as described above is not particularly limited, but as in the case of the crystalline polyester resin, the resin is dissolved in THF and purified by reprecipitation. It is desirable.
In the purified amorphous polyester resin, the amount of the component dissolved in methanol is in the desired range. In this case, the weight-average molecular weight (Mw) of the purified amorphous polyester resin is 8000 to 80000. The range is desirable, and the range of 12000 to 60000 is more desirable. Further, the molecular weight distribution (Mw / Mn), which is the ratio with the number average molecular weight (Mn), is preferably in the range of 2 to 10, and more preferably in the range of 2.5 to 8.

  Further, it is desirable that the DSC onset glass transition temperature (Tg) of the purified amorphous polyester resin is in the range of 45 to 70 ° C. and the residual monomer amount is 1000 ppm or less.

Note that the amorphous polyester resin and the crystalline polyester resin are taken out from the components contained in the toner to obtain the dissolved component amount, molecular weight, and the like by the following method.
First, the toner is dissolved in methyl ethyl ketone (MEK) at room temperature (20 to 25 ° C.). This is because when the toner contains a crystalline resin and an amorphous resin, almost only the amorphous resin is dissolved in MEK at room temperature. Accordingly, since the amorphous polyester resin is contained in the MEK-soluble component, the amorphous polyester resin can be obtained from the supernatant liquid separated by centrifugation after the dissolution. On the other hand, the solid content after centrifugation is heated and dissolved in THF, and this is heated and filtered with a glass filter to obtain a crystalline polyester resin. With respect to both resins thus obtained, the amount of dissolved components, molecular weight and the like are measured by the above method.

(Release agent)
The release agent used in the present embodiment is not particularly limited as long as it is a known release agent. For example, natural wax such as carnauba wax, rice wax, candelilla wax; synthetic or mineral / petroleum system such as low molecular weight polypropylene, low molecular weight polyethylene, sazol wax, microcrystalline wax, Fischer-Tropsch wax, paraffin wax, montan wax Examples thereof include, but are not limited to, waxes; higher fatty acids such as stearic acid and palmitic acid; ester waxes; Moreover, these mold release agents may be used individually by 1 type, and may be used together 2 or more types.
Among these, use of one or more selected from paraffin wax, carnauba wax and its modified wax, and ester wax is preferable from the viewpoint of exudation of the release agent to the toner surface at the time of melting.

  The melting point of the mold release agent is preferably 50 ° C. or higher, more preferably 60 ° C. or higher, from the viewpoint of storage stability. Moreover, it is preferable that it is 110 degrees C or less from a viewpoint of offset resistance, and it is more preferable that it is 100 degrees C or less.

  The content of the release agent is preferably in the range of 2 to 30 parts by mass and more preferably in the range of 5 to 20 parts by mass with respect to 100 parts by mass of the binder resin. When the content of the release agent is less than 2 parts by mass, there is no effect of adding the release agent, and hot offset at a high temperature may be caused. On the other hand, when the amount is more than 30 parts by mass, the charging property is deteriorated and the strength of the toner is reduced, so that the toner is easily destroyed and may cause carrier contamination.

(Coloring agent)
The colorant used in the present embodiment is not particularly limited as long as it is a known colorant. For example, carbon black such as furnace black, channel black, acetylene black and thermal black; inorganic pigment such as Bengala, bitumen and titanium oxide; azo pigment such as fast yellow, disazo yellow, pyrazolone red, chelate red, brilliant carmine and para brown Phthalocyanine pigments such as copper phthalocyanine and metal-free phthalocyanine; condensed polycyclic pigments such as flavantron yellow, dibromoanthrone orange, perylene red, quinacridone red and dioxazine violet;

More specifically, Chrome Yellow, Hansa Yellow, Benzidine Yellow, Slen Yellow, Quinoline Yellow, Permanent Orange GTR, Pyrarozone Orange, Vulcan Orange, Watch Young Red, Permanent Red, Dupont Oil Red, Resol Red, Rhodamine B Lake , Lake Red C, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Phthalocyanine Green, Malachite Green Oxalate, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 57: 1, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 74, C.I. I. Pigment blue 15: 1, C.I. I. Examples thereof include various pigments such as CI Pigment Blue 15: 3, and these can be used alone or in combination of two or more.

  The content of the colorant is preferably in the range of 1 to 30 parts by mass with respect to 100 parts by mass of the binder resin, but if necessary, a surface-treated colorant or a pigment dispersant is used. It is also effective to do. By appropriately selecting the type of the colorant, yellow toner, magenta toner, cyan toner, black toner and the like can be obtained.

(Other additives)
In the present embodiment, in addition to the above components, various components such as an internal additive, a charge control agent, inorganic powder (inorganic particles), and organic particles can be added as necessary.
As the internal additive, for example, metals such as ferrite, magnetite, reduced iron, cobalt, nickel, manganese, etc., magnetic materials such as alloys, compounds containing these metals, etc., or inorganic powders are mainly used as viscoelasticity of toner. All the additives that are added for the purpose of adjustment, such as silica, alumina, titania, calcium carbonate, magnesium carbonate, calcium phosphate, cerium oxide, etc., which are usually used as external additives on the toner surface as listed in detail below. Inorganic particles are exemplified. Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments.

  Examples of the external additive include various inorganic particles such as silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite. Diatomaceous earth, cerium chloride, bengara, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, silicon nitride and the like. Among them, silica fine particles and titanium oxide fine particles are preferable, and hydrophobized fine particles are particularly preferable.

The inorganic particles are generally used for the purpose of improving fluidity. The primary particle diameter of the inorganic particles is preferably 1 to 200 nm, and the addition amount is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the toner.
The organic particles are generally used for the purpose of improving cleaning properties and transfer properties, and specifically include polystyrene, polymethyl methacrylate, polyvinylidene fluoride, and the like.

Further, the toner of the present embodiment will be described in detail together with the manufacturing method thereof.
A method for producing the toner of the exemplary embodiment is not particularly limited, but is preferably a wet granulation method. Suitable examples of the wet granulation method include known melt suspension methods, emulsion aggregation methods, and dissolution suspension methods. Hereinafter, a particularly preferable emulsion aggregation method will be described as an example.

  The emulsion aggregation method includes a step (aggregation step) of forming an aggregated particle dispersion in a dispersion liquid (hereinafter sometimes referred to as “emulsion liquid”) in which at least resin particles are dispersed, and the aggregation This is a production method including a step of fusing the aggregated particles by heating the particle dispersion (fusion step). In addition, a step (adhesion step) of forming adhering particles by adding and mixing a particle dispersion in which particles are dispersed in the agglomerated particle dispersion and adhering the particles to the agglomerated particles between the aggregation step and the fusion step. It may be provided. In the adhesion step, the particle dispersion is added to and mixed with the aggregated particle dispersion prepared in the aggregation step, and the particles are adhered to the aggregated particles to form adhered particles. Corresponds to particles newly added to the aggregated particles as viewed from the aggregated particles, and is sometimes referred to as “additional particles”.

  As the additional particles, in addition to the resin particles, release agent particles, colorant particles and the like may be used singly or in combination. There is no restriction | limiting in particular as a method of adding and mixing the said particle dispersion liquid, For example, you may carry out gradually continuously, and may carry out in steps divided into several times. It is desirable to form a core-shell structure by the operation of adding such additional particles. The binder resin that is the main component of the write-once particles is a shell layer resin. If this method is used, the toner shape can be easily controlled by adjusting the temperature, the number of stirring, the pH and the like in the fusing step.

When an amorphous polyester resin or a crystalline polyester resin is used in the emulsion aggregation method, for example, an emulsification step of emulsifying the amorphous polyester resin to form emulsified particles (droplets) is preferably used.
In the emulsification step, for example, the emulsion particles (droplets) of the amorphous polyester resin are mixed with an aqueous medium and a mixed liquid (polymer liquid) containing a polyester resin and, if necessary, a colorant. It is formed by applying a shearing force. At that time, the viscosity of the polymer liquid can be lowered to form emulsified particles by heating to a temperature equal to or higher than the glass transition temperature of the amorphous polyester resin. Moreover, a dispersing agent can also be used for stabilization of emulsified particles and thickening of an aqueous medium. Hereinafter, such a dispersion of emulsified particles may be referred to as a “resin particle dispersion”.

  Examples of the emulsifier used when forming the emulsified particles include a homogenizer, a homomixer, a pressure kneader, an extruder, and a media disperser. The size of the emulsified particles (droplets) of the polyester resin is preferably in the range of 80 to 300 nm and more preferably in the range of 120 to 250 nm in terms of the average particle size (volume average particle size). If it is less than 80 nm, it is almost dissolved in water, making it difficult to produce particles. If it exceeds 300 nm, it may be difficult to obtain particles having a desired particle size of 3.0 to 7.5 μm. . The volume average particle size of the resin particles was measured with a Doppler scattering type particle size distribution analyzer (manufactured by Nikkiso Co., Ltd., Microtrac UPA9340).

  In this embodiment, it is desirable to use a phase inversion emulsification method to emulsify the resin. In the phase inversion emulsification method, at least a polyester resin is dissolved in an organic solvent, a neutralizing agent and a dispersion stabilizer are added as necessary, and an aqueous solvent is dropped under stirring to obtain emulsified particles. In this method, the solvent in the resin dispersion is removed to obtain an emulsion. At this time, the order of adding the neutralizing agent and the dispersion stabilizer may be changed.

  Examples of the organic solvent for dissolving the resin include formic acid esters, acetic acid esters, butyric acid esters, ketones, ethers, benzenes, and halogenated carbons. Specifically, esters such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl such as formic acid, acetic acid and butyric acid; acetone, MEK (methyl ethyl ketone), MPK (methyl propyl) Ketones), methyl ketones such as MIPK (methyl isopropyl ketone), MBK (methyl butyl ketone), MIBK (methyl isobutyl ketone), etc .; ethers such as diethyl ether and diisopropyl ether; heterocyclic substituents such as toluene, xylene and benzene Use carbon halides such as carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, etc., alone or in combination of two or more. Is possible That. Acetic acid esters, methyl ketones and ethers of low-boiling solvents (50 to 150 ° C.) are usually preferably used from the viewpoint of easy availability, ease of recovery during solvent removal, and environmental considerations, particularly acetone and methyl ethyl ketone. Those having partial solubility in water such as acetic acid, ethyl acetate, and butyl acetate are preferred. If the organic solvent remains in the resin particles, the surface of the heating member may be modified at the time of fixing. Therefore, it is desirable to use a relatively volatile organic solvent.

In the present embodiment, for example, an amorphous or crystalline polyester resin and the organic solvent are mixed, heated to 20 to 90 ° C., dissolved, and then added with water or before emulsification. It is desirable. Thereby, the stability of emulsified particles can be maintained by neutralizing carboxylic acid groups on the surface of the polyester resin and increasing hydrophilicity. Examples of the base include aqueous ammonia and aqueous solutions of sodium hydroxide, potassium hydroxide, sodium carbonate, and the like.
It is also desirable to add a salt or acid. Thereby, the particle size of emulsified particles (resin particles) can be kept large to some extent. The amount of the base added is desirably in the range of 1 to 10% by mass with respect to the resin.

  Furthermore, it is desirable to add acids and salts before or after adding the bases or before emulsifying. That is, when the resin is purified with methanol, low-molecular hydrophilic components in the resin are removed, making it difficult to control the particle size when preparing an emulsified dispersion of the resin. May get worse. In this case, it was found that an emulsified dispersion can be stably produced by adding an acid or salt to the system.

  Examples of the salt include salts such as sodium chloride and potassium chloride as they are, or an aqueous solution thereof or an organic solvent solution such as alcohol, or an aqueous ammonia solution. Examples of the acid include inorganic acids such as hydrochloric acid and nitric acid, organic acids such as acetic acid and citric acid, and monomers such as fumaric acid and maleic acid. These salts or acids are desirably soluble in water. The addition amount of the acid or salt is desirably in the range of 0.005 to 1% by mass with respect to the resin.

  As the aqueous solvent, ion-exchanged water is basically used, but a water-soluble organic solvent may be included so as not to destroy the oil droplets. Examples of water-soluble organic solvents include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol and other short carbon chain alcohols; ethylene glycol monomethyl ether, ethylene glycol Examples include ethylene glycol monoalkyl ethers such as monoethyl ether and ethylene glycol monobutyl ether; ethers, diols, THF, acetone and the like. The mixing ratio of these water-soluble organic solvents to ion-exchanged water is selected in the range of 1% to 50%, more preferably 1% to 30%, and used as an aqueous component. In addition, the water-soluble organic solvent may be added to the resin solution and used in addition to the ion-exchanged water to be added. In the case of adding a water-soluble organic solvent, the wettability between the resin and the resin dissolving solvent can be adjusted, and a function of reducing the liquid viscosity after the resin is dissolved can be expected.

  Moreover, you may add a dispersing agent to a resin solution and an aqueous component as needed so that the said emulsion may maintain a dispersed state stably. As the dispersant, a hydrophilic colloid is formed in an aqueous component, and in particular, cellulose derivatives such as hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose; polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polyacrylate, Synthetic polymers such as polymethacrylates; dispersion stabilizers such as gelatin; gum arabic; agar; Solid fine powders such as silica, titanium oxide, alumina, tricalcium phosphate, calcium carbonate, calcium sulfate, and barium carbonate can also be used. These dispersion stabilizers are usually added so that the concentration in the aqueous component is 0 to 20% by mass, preferably 0 to 10% by mass.

A surfactant is also used as the dispersant. As examples of the surfactant, those according to those used in the colorant dispersion described later can be used. For example, in addition to natural surfactant components such as saponins, cationic surfactants such as alkylamine hydrochlorides / acetates, quaternary ammonium salts, glycerols, fatty acid soaps, sulfates, alkylnaphthalene sulfonates, sulfones Anionic surfactants such as acid salts, phosphoric acid, phosphate esters, sulfosuccinates and the like can be mentioned, and anionic surfactants and nonionic surfactants are preferably used. In order to adjust the pH of the emulsion, a neutralizing agent may be added. As the neutralizing agent, general acids such as nitric acid, hydrochloric acid, sodium hydroxide and ammonia, and alkalis can be used.
As a method for removing the organic solvent from the emulsion, a method in which the organic solvent is volatilized at room temperature (20 to 25 ° C.) or under heating, and a method in which this is combined with reduced pressure are preferably used.

  As a dispersion method of the colorant and the release agent, for example, a general dispersion method such as a rotary shear type homogenizer, a ball mill having media, a sand mill, or a dyno mill can be used, and is not limited at all. .

If necessary, an aqueous dispersion of these colorants can be prepared using a surfactant, or an organic solvent dispersion of these colorants can be prepared using a dispersant. Hereinafter, the dispersion of the colorant and the release agent may be referred to as “colorant dispersion” or “release agent dispersion”.
The dispersant used for the colorant dispersion or the release agent dispersion station is generally a surfactant. Examples of the surfactant include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap; cationic surfactants such as amine salt type and quaternary ammonium salt type; polyethylene glycol Suitable examples include nonionic surfactants such as polyphenols, alkylphenol ethylene oxide adducts, and polyhydric alcohols. Among these, an ionic surfactant is preferable, and an anionic surfactant and a cationic surfactant are more preferable. The nonionic surfactant is preferably used in combination with the anionic surfactant or the cationic surfactant. The said surfactant may be used individually by 1 type, and may use 2 or more types together. Moreover, it is preferable that it is the same polarity as the dispersing agent used for other dispersion liquids, such as a mold release agent dispersion liquid.

  Specific examples of the anionic surfactant include fatty acid soaps such as potassium laurate, sodium oleate and sodium castor oil; sulfates such as octyl sulfate, lauryl sulfate, lauryl ether sulfate and nonyl phenyl ether sulfate; lauryl sulfonate , Dodecyl sulfonate, dodecyl benzene sulfonate, triisopropyl naphthalene sulfonate, dibutyl naphthalene sulfonate sodium alkylnaphthalene sulfonate, naphthalene sulfonate formalin condensate, monooctyl sulfosuccinate, dioctyl sulfosuccinate, lauric acid amide sulfonate, oleic acid amide sulfonate Sulfonates such as lauryl phosphate, isopropyl phosphate, Phosphoric acid esters such as alkenyl phenyl ether phosphates; dialkyl sodium sulfosuccinates of sodium dioctyl sulfosuccinate, sodium lauryl sulfosuccinate 2, polyoxyethylene sulfo sulfosuccinate salts such as succinic acid lauryl disodium and the like. Of these, alkylbenzene sulfonate compounds such as dodecylbenzene sulfonate and its branched products are preferred.

  Specific examples of the cationic surfactant include laurylamine hydrochloride, stearylamine hydrochloride, oleylamine acetate, stearylamine acetate, stearylaminopropylamine acetate, and other amine salts; lauryltrimethylammonium chloride, dilauryldimethylammonium Chloride, distearyl ammonium chloride, distearyl dimethyl ammonium chloride, lauryl dihydroxyethyl methyl ammonium chloride, oleyl bispolyoxyethylene methyl ammonium chloride, lauroylaminopropyldimethylethylammonium ethosulphate, lauroylaminopropyldimethylhydroxyethylammonium perchlorate, alkylbenzene dimethyl Ammonium chloride, alkylto Such as quaternary ammonium salts such as ammonium chloride.

  Specific examples of the nonionic surfactant include polyoxyethylene octyl ether, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether and other alkyl ethers; Alkylphenyl ethers such as oxyethylene nonylphenyl ether; alkyl esters such as polyoxyethylene laurate, polyoxyethylene stearate, polyoxyethylene oleate; polyoxyethylene lauryl amino ether, polyoxyethylene stearyl amino ether, polyoxy Alkylamines such as ethylene oleyl amino ether, polyoxyethylene soybean amino ether, polyoxyethylene beef tallow amino ether; Alkyl amides such as xylethylene lauric acid amide, polyoxyethylene stearic acid amide, polyoxyethylene oleic acid amide; vegetable oil ethers such as polyoxyethylene castor oil ether, polyoxyethylene rapeseed oil ether; lauric acid diethanolamide, stearin Alkanolamides such as acid diethanolamide and oleic acid diethanolamide; sorbitan ester ethers such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate And the like.

  The addition amount of the dispersant used is desirably 2% by mass or more and 30% by mass or less, and more preferably 5% by mass or more and 20% by mass or less with respect to the colorant or the release agent. If the amount of the dispersant is too small, the particle size may not be reduced, or the storage stability of the dispersion may be reduced. On the other hand, when the amount is too large, the amount of the dispersant remaining in the toner increases, and the chargeability and powder fluidity of the toner may be reduced.

  The aqueous dispersion medium to be used is preferably one having few impurities such as metal ions such as distilled water and ion exchange water. In addition, alcohol or the like can be added for the purpose of defoaming or adjusting the surface tension. Moreover, polyvinyl alcohol, a cellulose polymer, etc. can also be added for viscosity adjustment.

  The means for preparing the dispersion of the various additives is not particularly limited, and examples thereof include a ball mill, a sand mill, and a dyno mill having a rotary shearing homogenizer and a media, as well as a colorant dispersion and a release agent. Examples of the dispersion apparatus known per se include an apparatus according to the one used for the preparation of the dispersion, and an optimum apparatus can be selected and used.

  In the aggregation step, it is preferable to use an aggregating agent in order to form aggregated particles. Examples of the flocculant used include a surfactant having a polarity opposite to that of the surfactant used in the dispersant, a general inorganic metal compound (inorganic metal salt), or a polymer thereof. The metal element constituting the inorganic metal salt has a divalent or higher charge belonging to the 2A, 3A, 4A, 5A, 6A, 7A, 8, 1B, 2B, 3B group in the periodic table (long periodic table). There is no limitation as long as it dissolves in the form of ions in the aggregation system of resin particles.

  Specific examples of the inorganic metal salt include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate, and polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide. And inorganic metal salt polymers. Among these, an aluminum salt and a polymer thereof are particularly preferable. In general, in order to obtain a sharper particle size distribution, even if the valence of the inorganic metal salt is divalent to monovalent, bivalent to trivalent or higher, and even to the same valence, the polymerization type inorganic metal salt weight Combined is more suitable.

  The amount of the flocculant added varies depending on the type and valence of the flocculant, but is generally in the range of 0.05 to 0.1% by mass. The aggregating agent does not always remain in the toner due to outflow into the aqueous medium or formation of coarse powder during the toner forming process. In particular, when the amount of the solvent in the resin is large in the toner forming step, the solvent and the flocculant interact and easily flow out into the aqueous medium, so it is necessary to adjust the amount according to the amount of the remaining solvent.

  In the fusion step, the agglomeration suspension is brought to a pH of 5 to 10 under stirring according to the agglomeration step to stop the agglomeration, and the resin has a glass transition temperature (Tg) or higher. The aggregated particles are fused and united by heating at a temperature (or a temperature equal to or higher than the melting point of the crystalline resin). The heating time may be as long as desired coalescence is achieved, and may be performed for about 0.2 to 10 hours. Thereafter, when the temperature is lowered to Tg or less of the resin to solidify the particles, the particle shape and surface properties change depending on the temperature lowering rate. For example, when the temperature is lowered at a high speed, spheroidization and surface irregularities tend to decrease, and conversely, when the temperature is lowered slowly, the particle shape becomes irregular and irregularities are likely to occur on the particle surface. Therefore, it is preferable to lower the temperature to at most Tg of the resin at a rate of at least 0.5 ° C./min, more preferably at a rate of 1.0 ° C./min or more.

  Further, while heating at a temperature equal to or higher than the Tg of the resin, particles are grown by adding a pH or a flocculant according to the aggregation step, and when the desired particle size is reached, at least 0.5 ° C. according to the case of the fusion step. It is preferable in terms of simplification of the process because the aggregation process and the fusion process can be performed at the same time if the particle growth is stopped simultaneously with the solidification by lowering the temperature to the Tg of the resin at a rate of / min. It may be difficult to make a core-shell structure.

  After completing the fusing step, the particles are washed and dried to obtain toner particles. Considering the chargeability of the toner, it is preferable to perform substitution cleaning with ion-exchanged water, and the degree of cleaning is generally monitored by the conductivity of the filtrate, so that the conductivity finally becomes 25 μS / cm or less. It is preferable to make it. The washing may include a step of neutralizing ions with an acid or an alkali. The treatment with an acid preferably has a pH of 4.0 or less, and the treatment with an alkali preferably has a pH of 8.0 or more. The solid-liquid separation after washing is not particularly limited, but from the viewpoint of productivity, suction filtration, pressure filtration such as a filter press, and the like are preferably used. Further, the drying method is not particularly limited, but from the viewpoint of productivity, freeze drying, flash jet drying, fluidized drying, vibration fluidized drying, etc. are preferably used, and the final toner moisture content is 1% by mass or less. More preferably, drying is performed so that the content is 0.7% by mass or less.

  The toner particles obtained as described above can be externally mixed with inorganic particles and organic particles as fluidity aids, cleaning aids, abrasives, and the like. Examples of the inorganic particles include all particles usually used as external additives on the toner surface, such as silica, alumina, titanium oxide, calcium carbonate, magnesium carbonate, tricalcium phosphate, and cerium oxide. These inorganic particles preferably have a hydrophobic surface, and are used to control various toner characteristics such as chargeability, powder characteristics, and storage stability, and system suitability such as developability and transferability. It is done. As organic particles, for example, they are usually used as external additives on the surface of toner such as vinyl resins such as styrene polymers, (meth) acrylic polymers, and ethylene polymers, polyester resins, silicone resins, and fluorine resins. All particles.

These particles are added for the purpose of improving transferability, and the primary particle size is preferably 0.05 to 1.0 μm. Further, a lubricant can be added. Examples of the lubricant include fatty acid amides such as ethylene bisstearyl amide and oleic acid amide, and higher alcohols such as fatty acid metal salt unilin such as zinc stearate and calcium stearate. These are generally added for the purpose of improving the cleaning property, and those having a primary particle size of 0.150 μm are used.
The external additive is adhered or fixed to the toner surface by applying a mechanical impact force with a sample mill or a Henschel mixer.

(Toner characteristics)
The volume average particle size of the toner in the exemplary embodiment is desirably in the range of 4 to 9 μm, more desirably in the range of 4.5 to 8.5 μm, and further desirably in the range of 5 to 8 μm. When the volume average particle size is smaller than 4 μm, the toner fluidity is lowered, the chargeability of each particle is likely to be lowered, and the charge distribution is widened, so that fogging on the background and toner spillage from the developing device are likely to occur. . On the other hand, if it is smaller than 4 μm, the cleaning property may be extremely difficult. If the volume average particle size is larger than 9 μm, the resolution decreases, so that sufficient image quality cannot be obtained, and it may be difficult to satisfy recent high image quality requirements.

Further, the toner according to the exemplary embodiment draws a cumulative distribution from the small diameter side in each of the volume and the number in the particle size range (channel) obtained by dividing the particle size distribution measured by the following method. Volume average calculated from (D84% / D16%) ^1/2 when the diameter is defined as volume D16% and the particle diameter at 50% cumulative is defined as volume D84%. The particle size distribution index (GSDv) is preferably 1.15 to 1.30, and more preferably 1.15 to 1.25.

  The volume average particle diameter and the like can be measured using Multisizer II (manufactured by Beckman Coulter, Inc.) with an aperture diameter of 50 μm. At this time, the measurement was performed after the toner was dispersed in an electrolyte aqueous solution (isoton aqueous solution) (concentration: 10% by mass) and dispersed by ultrasonic waves for 30 seconds or more. As for the particle size distribution, the particle size range divided on the basis of the particle size distribution measured using Multisizer II (divided number: from 1.26 to 50.8 μm in 16 channels, 0.1 in log scale) Specifically, the channel 1 is 1.26 μm or more and less than 1.59 μm, the channel 2 is 1.59 μm or more and less than 2.00 μm, the channel 3 is 2.00 μm or more and less than 2.52 μm. The log values of the lower limit value on the left side are (log1.26 =) 0.1, (log1.59 =) 0.2, (log2.00 =) 0.3, ..., 1.6 In other words, the cumulative distribution is subtracted from the small particle diameter side, and the particle diameter that becomes 16% is the volume D16v, the number D16p, and the particle diameter that is 50% is the volume. D50v (volume average grain ), Number D50p, volume particle size at a cumulative 84% D84v, was defined as the number D84p.

Further, the toner of the present invention preferably has a spherical shape with a shape factor SF1 in the range of 110 to 140. When the shape is spherical in this range, transfer efficiency and image density are improved, and high-quality image formation can be performed.
The shape factor SF1 is more preferably in the range of 110 to 130.

Here, the shape factor SF1 is obtained by the following equation (1).
SF1 = (ML ² / A) × (π / 4) × 100 (1)
In the above formula (1), ML represents the absolute maximum length of the toner particles, and A represents the projected area of the toner particles.

  The SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope (SEM) image using an image analyzer, and can be calculated as follows, for example. That is, an optical microscope image of toner particles dispersed on the surface of a slide glass is taken into a Luzex image analyzer through a video camera, the maximum length and projected area of 100 particles are obtained, calculated by the above equation (1), and the average value thereof Is obtained.

<Electrostatic image developer>
The electrostatic image developing toner of the present invention is used as it is as a one-component developer or as a two-component developer composed of a carrier, but a two-component developer excellent in charge maintenance and stability is desirable. Hereinafter, the embodiment of the two-component developer will be described.

  The carrier is preferably a carrier coated with a resin, and more preferably a carrier coated with a nitrogen-containing resin. Examples of the nitrogen-containing resin include acrylic resins containing dimethylaminoethyl methacrylate, dimethylacrylamide, acrylonitrile and the like, amino resins containing urea, urethane, melamine, guanamine, aniline, amide resins, and urethane resins. These copolymer resins may also be used. As the carrier coating resin, two or more of the nitrogen-containing resins may be used in combination. Moreover, you may use combining the said nitrogen containing resin and resin which does not contain nitrogen. The nitrogen-containing resin may be used in the form of particles and dispersed in a resin not containing nitrogen. In particular, urea resins, urethane resins, melamine resins, and amide resins have high negative chargeability and high resin hardness, so that a decrease in charge amount due to peeling of the coating resin can be effectively suppressed.

In general, the carrier needs to have an appropriate electric resistance value, and specifically, an electric resistance value of about 10 ⁹ to 10 ¹⁴ Ωcm is required. For example, when the electrical resistance value is as low as 10 ⁶ Ωcm as in the case of an iron powder carrier, the carrier adheres to the image portion of the photoreceptor due to charge injection from the sleeve, or the latent image charge escapes through the carrier, and the latent image In some cases, problems such as disturbance of the image or loss of images may occur. On the other hand, if an insulating resin (volume resistivity of 10 ¹⁴ Ωcm or more) is thickly coated, the electric resistance value becomes too high and carrier charges are less likely to leak, resulting in an edged image. On the other hand, there may be a problem of an edge effect that the image density in the central portion becomes very thin on a large image area. Therefore, it is desirable to disperse the conductive powder in the resin coating layer in order to adjust the resistance of the carrier.

  Specific examples of the conductive powder include metals such as gold, silver and copper; carbon black; semiconductive oxides such as titanium oxide and zinc oxide; titanium oxide, zinc oxide, barium sulfate, aluminum borate and potassium titanate. And the like, such as powder coated with tin oxide, carbon black, or metal. Among these, carbon black is preferable from the viewpoint of production stability, cost, and conductivity.

  Examples of the method for forming the resin coating layer on the surface of the carrier core material include an immersion method in which a powder of the carrier core material is immersed in the solution for forming the coating layer, and a solution for forming the coating layer on the surface of the carrier core material. Spraying method for spraying, fluidized bed method for spraying the solution for forming the coating layer in a state where the carrier core material is floated by flowing air, and a kneader for mixing the carrier core material and the coating layer forming solution in a kneader coater to remove the solvent. Examples of the coater method include a powder coating method in which a coating resin is formed into particles and mixed at a temperature equal to or higher than the melting point of the coating resin in a carrier core material and a kneader coater and then cooled to form a coating. The kneader coating method and the powder coating method are particularly preferably used. The average film thickness of the resin coating layer formed by the above method is usually in the range of 0.1 to 10 μm, more preferably 0.2 to 5 μm.

The core material (carrier core material) used for the carrier is not particularly limited, and examples thereof include magnetic metals such as iron, steel, nickel, and cobalt, or magnetic oxides such as ferrite and magnetite, glass beads, and the like. From the viewpoint of using the magnetic brush method, a magnetic carrier is desirable. As an average particle diameter of a carrier core material, generally 10-100 micrometers is preferable and 20-80 micrometers is more preferable.
The mixing ratio (mass ratio) of the toner and the carrier in the two-component developer is in the range of toner: carrier = 1: 100 to 30: 100, more preferably in the range of 3: 100 to 20: 100. desirable.

<Image forming apparatus>
Next, the image forming apparatus of the present invention using the electrostatic image developing toner of the present invention will be described.
The image forming apparatus of the present invention includes an image carrier, a developing unit that develops an electrostatic image formed on the image carrier as a toner image with a developer, and a toner image formed on the image carrier. The image forming apparatus includes a transfer unit that transfers onto a transfer body and a fixing unit that fixes a toner image transferred onto the transfer body, and uses the electrostatic image developer of the present invention as the developer.

In this image forming apparatus, for example, the part including the developing unit may have a cartridge structure (process cartridge) that can be attached to and detached from the image forming apparatus main body. As the process cartridge, a developer holding body is used. The process cartridge of the present invention that contains at least the electrostatic image developer of the present invention is preferably used.
Hereinafter, an example of the image forming apparatus of the present invention will be described by way of an embodiment, but the present invention is not limited to this. In addition, the main part shown to a figure is demonstrated and the description is abbreviate | omitted about others.

  FIG. 1 is a schematic diagram showing a quadruple tandem full-color image forming apparatus. The image forming apparatus shown in FIG. 1 is a first to first electrophotographic method that outputs yellow (Y), magenta (M), cyan (C), and black (K) images based on color-separated image data. Fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) are provided. These image forming units (hereinafter simply referred to as “units”) 10Y, 10M, 10C, and 10K are juxtaposed at a predetermined distance in the horizontal direction. The units 10Y, 10M, 10C, and 10K may be process cartridges that are detachable from the main body of the image forming apparatus.

Above each of the units 10Y, 10M, 10C, and 10K, an intermediate transfer belt 20 as an intermediate transfer member is extended through each unit. The intermediate transfer belt 20 is provided by being wound around a driving roller 22 and a support roller 24 that are in contact with the inner surface of the intermediate transfer belt 20 that are spaced apart from each other from the left to the right in the drawing. It is designed to travel in the direction toward 10K. The support roller 24 is biased in a direction away from the drive roller 22 by a spring or the like (not shown), and a predetermined tension is applied to the intermediate transfer belt 20 wound around both. Further, an intermediate transfer member cleaning device 30 is provided on the side of the image carrier of the intermediate transfer belt 20 so as to face the driving roller 22.
Further, each of the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K includes yellow, magenta, cyan, and black contained in the toner cartridges 8Y, 8M, 8C, and 8K. The four color toners can be supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K described above have the same configuration, here, the first unit that forms a yellow image disposed on the upstream side in the intermediate transfer belt traveling direction. 10Y will be described as a representative. Note that the second to fourth units are denoted by reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) in the same parts as the first unit 10Y. Description of 10M, 10C, 10K is omitted.

The first unit 10Y has a photoreceptor 1Y that functions as an image holding member. Around the photoreceptor 1Y, an electrostatic charge image is formed by exposing the surface of the photoreceptor 1Y to a predetermined potential with a charging roller 2Y and the charged surface with a laser beam 3Y based on the color-separated image signal. An exposure device 3; a developing device (developing means) 4Y for supplying the charged toner to the electrostatic image and developing the electrostatic image; a primary transfer roller 5Y (primary) for transferring the developed toner image onto the intermediate transfer belt 20; A transfer unit), and a photoconductor cleaning device (cleaning unit) 6Y for removing toner remaining on the surface of the photoconductor 1Y after the primary transfer.
The primary transfer roller 5Y is disposed inside the intermediate transfer belt 20, and is provided at a position facing the photoreceptor 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rollers 5Y, 5M, 5C, and 5K. Each bias power source varies the transfer bias applied to each primary transfer roller under the control of a control unit (not shown).

Hereinafter, an operation of forming a yellow image in the first unit 10Y will be described. First, prior to the operation, the surface of the photoreceptor 1Y is charged to a potential of about −600V to −800V by the charging roller 2Y.
The photoreceptor 1Y is formed by laminating a photosensitive layer on a conductive substrate (volume resistivity at 20 ° C .: 1 × 10 ⁻⁶ Ωcm or less). This photosensitive layer usually has a high resistance (a resistance equivalent to that of a general resin), but has a property that the specific resistance of the portion irradiated with the laser beam changes when irradiated with the laser beam 3Y. Therefore, a laser beam 3Y is output to the surface of the charged photoreceptor 1Y via the exposure device 3 in accordance with yellow image data sent from a control unit (not shown). The laser beam 3Y is applied to the photosensitive layer on the surface of the photoreceptor 1Y, whereby an electrostatic latent image of a yellow print pattern is formed on the surface of the photoreceptor 1Y.

The electrostatic latent image is an image formed on the surface of the photoreceptor 1Y by charging, and the specific resistance of the irradiated portion of the photosensitive layer is lowered by the laser beam 3Y, and the charged charge on the surface of the photoreceptor 1Y is reduced. On the other hand, it is a so-called negative latent image formed by the charge remaining in the portion not irradiated with the laser beam 3Y.
The electrostatic latent image formed on the photoreceptor 1Y in this way is rotated to a predetermined development position as the photoreceptor 1Y travels. Then, at this development position, the electrostatic latent image on the photoreceptor 1Y is converted into a visible image (developed image) by the developing device 4Y.

  In the developing device 4Y, for example, yellow toner having a volume average particle diameter of 7 μm containing at least a yellow colorant, a crystalline polyester resin, and an amorphous polyester resin is accommodated. The yellow toner is triboelectrically charged by being agitated inside the developing device 4Y, and has a charge of the same polarity (negative polarity) as the charged charge on the photoreceptor 1Y, and a developer roll (developer holder). Is held on. As the surface of the photoreceptor 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the latent image portion on the surface of the photoreceptor 1Y, and the latent image is developed with the yellow toner. . The photoreceptor 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

When the yellow toner image on the photoreceptor 1Y is conveyed to the primary transfer, a predetermined primary transfer bias is applied to the primary transfer roller 5Y, and the electrostatic force directed from the photoreceptor 1Y to the primary transfer roller 5Y generates a toner image. The toner image on the photoreceptor 1 </ b> Y is transferred onto the intermediate transfer belt 20. The transfer bias applied at this time is a (+) polarity opposite to the polarity (−) of the toner, and is controlled to about +10 μA by the control unit (not shown) in the first unit 10Y, for example.
On the other hand, the toner remaining on the photoreceptor 1Y is removed and collected by the cleaning device 6Y.

Further, the primary transfer bias applied to the primary transfer rollers 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
Thus, the intermediate transfer belt 20 onto which the yellow toner image has been transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superimposed and transferred in a multiple manner.

  The intermediate transfer belt 20 onto which the four color toner images have been transferred in multiple layers through the first to fourth units is disposed on the image transfer surface side of the intermediate transfer belt 20 and the support roller 24 in contact with the inner surface of the intermediate transfer belt 20. The secondary transfer roller (secondary transfer means) 26 is connected to a secondary transfer portion. On the other hand, the recording paper (transfer object) P is fed at a predetermined timing into a gap where the secondary transfer roller 26 and the intermediate transfer belt 20 are pressed against each other via a supply mechanism, and a predetermined secondary transfer bias is supported. Applied to the roller 24. The transfer bias applied at this time is a (−) polarity that is the same polarity as the polarity (−) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P is applied to the toner image, and the transfer bias is applied to the intermediate transfer belt 20. The toner image is transferred onto the recording paper P. Note that the secondary transfer bias at this time is determined according to the resistance detected by a resistance detecting means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

Thereafter, the recording paper P is sent to a fixing device (fixing means) 28, where the toner image is heated, and the color-superposed toner image is melted and fixed on the recording paper P. The recording paper P on which the color image has been fixed is carried out toward the discharge unit, and a series of color image forming operations is completed.
The image forming apparatus exemplified above is configured to transfer the toner image onto the recording paper P via the intermediate transfer belt 20, but the present invention is not limited to this configuration, and the toner image is directly transferred from the photoconductor. It may be a structure that is transferred to a recording sheet.

<Process cartridge, toner cartridge>
FIG. 2 is a schematic configuration diagram showing a preferred example of a process cartridge containing the electrostatic charge image developer of the present invention. In the process cartridge 200, a charging roller 108, a developing device 111, a photoconductor cleaning device (cleaning means) 113, an opening 118 for exposure, and an opening 117 for static elimination exposure are attached to a rail 116 together with the photoconductor 107. Are combined and integrated with each other.
The process cartridge 200 is detachable from an image forming apparatus main body including a transfer device 112, a fixing device 115, and other components (not shown). It forms a forming apparatus. Reference numeral 300 denotes a recording sheet.

  The process cartridge shown in FIG. 2 includes a charging device 108, a developing device 111, a cleaning device (cleaning means) 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. Can be selectively combined. In the process cartridge of the present invention, in addition to the photosensitive member 107, from the charging device 108, the developing device 111, the cleaning device (cleaning means) 113, the opening 118 for exposure, and the opening 117 for static elimination exposure. It comprises at least one selected from the group consisting of.

  Next, the toner cartridge of the present invention will be described. The toner cartridge of the present invention is detachably attached to the image forming apparatus, and at least the toner cartridge for storing toner to be supplied to the developing means provided in the image forming apparatus, the toner described above. Toner. It should be noted that at least the toner may be stored in the toner cartridge according to the present exemplary embodiment. For example, a developer may be stored depending on the mechanism of the image forming apparatus.

  Therefore, in the image forming apparatus having a configuration in which the toner cartridge can be attached and detached, by using the toner cartridge containing the toner, storability can be maintained even in a toner cartridge whose container is miniaturized, It is possible to achieve low-temperature fixing while maintaining high image quality.

  The image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which the toner cartridges 8Y, 8M, 8C, and 8K can be attached and detached, and the developing devices 4Y, 4M, 4C, and 4K are respectively the developing devices ( And a toner supply pipe (not shown). Further, when the amount of toner stored in the toner cartridge is low, the toner cartridge can be replaced.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely using an Example, this invention is not limited by the following Example.

<Measuring method of various characteristics>
First, methods for measuring physical properties of toners and the like used in Examples and Comparative Examples will be described. Note that all or part of the details described above are omitted.
(Measurement method of molecular weight and molecular weight distribution of resin)
In the present invention, the molecular weight and molecular weight distribution of the crystalline polyester resin and the like were measured by GPC using the “HLC-8120GPC, SC-8020 (manufactured by Tosoh Corporation) apparatus” under the above-mentioned conditions.

(Volume average particle diameter of resin particles, colorant particles, etc.)
Volume average particle diameters of resin particles, colorant particles, and the like were measured with a Doppler scattering type particle size distribution measuring apparatus (manufactured by Nikkiso Co., Ltd., Microtrac UPA 9340).

(Measuring method of melting point and glass transition temperature of resin)
The melting point of the crystalline resin and the glass transition point (Tg) of the amorphous resin were determined according to ASTM D3418-8, using a differential scanning calorimeter (manufactured by Mac Science: DSC3110, thermal analysis system 001) under the conditions described above. It was measured by. In addition, melting | fusing point was made into the peak temperature of an endothermic peak, and the glass transition point was made into the temperature of the intermediate point in the step-like endothermic change.

(Amount of components dissolved in methanol in toner and resin)
100 g of tetrahydrofuran was added to 20 g of toner (resin), heated and stirred at 40 ° C., held for 30 minutes, cooled to room temperature, and then filtered with a glass filter. The filtrate was added dropwise to a container containing 300 g of methanol over 10 minutes while stirring the methanol, and stirring was continued for 30 minutes after the addition. This was filtered, the filtrate was desolvated, dried and weighed, and the weight was divided by the weight of the original toner (resin) to obtain the amount (%) of methanol-soluble component.

<Preparation of each dispersion>
(Synthesis of polyester resin)
-Crystalline polyester resin (1)-
In a three-necked flask, 100 parts by mass of sebacic acid, 58.4 parts by mass of hexanediol and 0.10 parts by mass of dibutyltin oxide were added and reacted at 180 ° C. for 6 hours in a nitrogen atmosphere. During the reaction, generated water was removed out of the system. Thereafter, while gradually reducing the pressure, the temperature was raised to 210 ° C. and reacted for 4 hours, followed by cooling to obtain a crystalline polyester resin (1). The crystalline polyester resin (1) had a weight average molecular weight (Mw) of 18500 and a melting point of 75.8 ° C.

50 parts by mass of the obtained crystalline polyester resin (1) was added to 100 parts by mass of tetrahydrofuran, heated to 60 ° C. with stirring, held for 30 minutes, and then dropped into 100 parts by mass of methanol. The precipitated solid content was separated by filtration, and the solid content was dried under reduced pressure to obtain a purified product of crystalline polyester resin (1).
The amount of components dissolved in methanol of this purified product was 0.1% by mass, and Mw / Mn was 2.9.

-Crystalline polyester resin (2)-
A three-necked flask was charged with 100 parts by mass of dodecanediacide, 69.6 parts by mass of nonanediol and 0.10 parts by mass of dibutyltin oxide, and reacted at 180 ° C. for 6 hours in a nitrogen atmosphere. During the reaction, generated water was removed out of the system. Thereafter, while gradually reducing the pressure, the temperature was raised to 220 ° C. and reacted for 2 hours, followed by cooling to obtain a crystalline polyester resin (2). The crystalline polyester resin (2) had a weight average molecular weight of 14600 and a melting point of 77.5 ° C.

50 parts by mass of the obtained crystalline polyester resin (2) was added to 100 parts by mass of tetrahydrofuran, heated to 60 ° C. with stirring, held for 30 minutes, and then dropped into 100 parts by mass of methanol. The precipitated solid content was separated by filtration, and the solid content was dried under reduced pressure to obtain a purified product of crystalline polyester resin (2).
The amount of this dissolved product dissolved in methanol was 0.1% by mass, and Mw / Mn was 3.3.

-Crystalline polyester resin (3)-
A three-necked flask was charged with 100 parts by mass of dimethyl sebacate, 100 parts by mass of ethylene glycol, and 0.08 parts by mass of dibutyltin oxide, and reacted at 180 ° C. for 6 hours in a nitrogen atmosphere. During the reaction, generated water was removed out of the system. Thereafter, while gradually reducing the pressure, the temperature was raised to 220 ° C. and reacted for 5 hours, followed by cooling to obtain a crystalline polyester resin (3). The weight average molecular weight of the crystalline polyester resin (3) was 25900, and the melting point was 70.6 ° C.

50 parts by mass of the obtained crystalline polyester resin (3) was added to 100 parts by mass of tetrahydrofuran, heated to 60 ° C. with stirring, held for 30 minutes, and then dropped into 100 parts by mass of methanol. The precipitated solid content was separated by filtration, and the solid content was dried under reduced pressure to obtain a purified product of crystalline polyester resin (3).
The amount of components dissolved in methanol of this purified product was 0.2% by mass, and Mw / Mn was 4.5.

-Amorphous polyester resin (1)-
In a three-necked flask, 50 parts by mass of terephthalic acid, 26 parts by mass of bisphenol A ethylene oxide adduct, 160 parts by mass of bisphenol A propylene oxide adduct, 19 parts by mass of fumaric acid, 21 parts by mass of dodecenyl succinic acid and 0.23 parts by mass of dibutyltin oxide And allowed to react at 180 ° C. for 3 hours in a nitrogen atmosphere. During the reaction, generated water was removed out of the system. Thereafter, while gradually reducing the pressure, the temperature was raised to 240 ° C. and reacted for 2 hours, followed by cooling to obtain an amorphous polyester resin (1). The amorphous polyester resin (1) had a weight average molecular weight of 17,200 and a glass transition point (Tg) of 60.5 ° C.

50 parts by mass of the obtained amorphous polyester resin (1) was added to 100 parts by mass of tetrahydrofuran, heated to 40 ° C. with stirring, held for 30 minutes, and then dropped into 100 parts by mass of methanol. The precipitated solid content was separated by filtration, and the solid content was dried under reduced pressure to obtain a purified product of amorphous polyester resin (1).
The amount of components dissolved in methanol of this purified product was 0.5% by mass, and Mw / Mn was 2.8.

-Amorphous polyester resin (2)-
In a three-necked flask, 50 parts by mass of terephthalic acid, 81 parts by mass of bisphenol A ethylene oxide adduct, 72 parts by mass of bisphenol A propylene oxide adduct, 3 parts by mass of fumaric acid, 30 parts by mass of dodecenyl succinic acid, 5 parts by mass of trimellitic acid and dibutyl 0.25 part by mass of tin oxide was added and reacted at 180 ° C. for 3 hours in a nitrogen atmosphere. During the reaction, generated water was removed out of the system. Thereafter, while gradually reducing the pressure, the temperature was raised to 240 ° C. and reacted for 5 hours, followed by cooling to obtain an amorphous polyester resin (2). The amorphous polyester resin (2) had a weight average molecular weight of 47200 and Tg of 58.7 ° C.

50 parts by mass of the obtained amorphous polyester resin (2) was added to 100 parts by mass of tetrahydrofuran, heated to 40 ° C. with stirring and held for 30 minutes, and then dropped into 100 parts by mass of methanol. The precipitated solid content was separated by filtration, and the solid content was dried under reduced pressure to obtain a purified product of an amorphous polyester resin (2).
The amount of this dissolved product dissolved in methanol was 0.6% by mass, and Mw / Mn was 4.1.

(Preparation of each dispersion)
-Crystalline polyester resin dispersion (A1)-
In a three-necked flask, 100 parts by weight of a purified product of crystalline polyester resin (1), 50 parts by weight of ethyl acetate and 30 parts by weight of 2-propyl alcohol are added and heated to 60 ° C. while stirring with a three-one motor. After dissolution, 25 parts by mass of a 10% aqueous ammonia solution was added. Further, 400 parts by mass of ion-exchanged water was gradually added to perform phase inversion emulsification, and then the solvent was removed. Thereafter, ion exchange water was added to adjust the solid content concentration to 20% by mass to obtain a crystalline polyester resin dispersion (A1). The volume average particle size of the resin particles in the dispersion was 148 nm, and the volume particle size distribution index (GSDv) was 1.28.

-Crystalline polyester resin dispersion (A2)-
A crystalline polyester resin dispersion (A2) is produced under the same conditions as the production of the crystalline polyester resin dispersion (A1) except that the crystalline polyester resin (2) is used instead of the crystalline polyester resin (1). did.
The volume average particle size of the resin particles in the dispersion was 162 nm, and the volume particle size distribution index (GSDv) was 1.25.

-Crystalline polyester resin dispersion (A3)-
A crystalline polyester resin dispersion (A3) is produced under the same conditions as the production of the crystalline polyester resin dispersion (A1) except that the crystalline polyester resin (3) is used instead of the crystalline polyester resin (1). did.
The volume average particle diameter of the resin particles in the dispersion was 203 nm, and the volume particle size distribution index (GSDv) was 1.26.

-Crystalline polyester resin dispersion (A4)-
A crystalline polyester resin dispersion (A1) that was not subjected to solvent removal was prepared, and this was used as a crystalline polyester resin dispersion (A4).

-Amorphous polyester resin dispersion (B1)-
In a three-necked flask, 100 parts by mass of a purified product of amorphous polyester resin (1), 50 parts by mass of methyl ethyl ketone and 20 parts by mass of 2-propyl alcohol were added, and the resin was dissolved while stirring with a three-one motor. 5 parts by mass of an aqueous ammonia solution was added. Further, 350 parts by mass of ion-exchanged water was gradually added to perform phase inversion emulsification, and then the solvent was removed. Thereafter, ion-exchanged water was added to adjust the solid content concentration to 30% by mass to obtain an amorphous polyester resin dispersion (B1). The volume average particle diameter of the resin particles in the dispersion was 146 nm, and the volume particle size distribution index (GSDv) was 1.27.

-Amorphous polyester resin dispersion (B2)-
In a three-necked flask, 100 parts by mass of amorphous polyester resin (2), 50 parts by mass of methyl ethyl ketone, 15 parts by mass of 2-propyl alcohol, and 0.05 parts by mass of trimellitic acid were added, and the resin was stirred while being stirred with a three-one motor. After dissolution, 22 parts by mass of a 10% aqueous ammonia solution was added. Further, 350 parts by mass of ion-exchanged water was gradually added to perform phase inversion emulsification, and then the solvent was removed. Thereafter, ion exchange water was added to adjust the solid content concentration to 30% by mass to obtain an amorphous polyester resin dispersion (B2). The volume average particle size of the resin particles in the dispersion was 152 nm, and the volume particle size distribution index (GSDv) was 1.22.

-Colorant dispersion (C)-
100 parts by mass of cyan pigment (CI Pigment Blue 15: 3, copper phthalocyanine, manufactured by Dainichi Seika Co., Ltd.), 5 parts by mass of an anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 450 parts by mass of ion-exchanged water The components were mixed and dispersed with a high-pressure impact disperser Ultimizer (HJP30006, manufactured by Sugino Machine Co., Ltd.) at a pressure of 250 mPa for 1 hour to obtain a cyan colorant dispersion (C). The volume average particle size of the colorant in this colorant dispersion was 166 nm, and the solid content concentration was 24.3% by mass.

-Colorant dispersion (M)-
100 parts by mass of magenta pigment (CI Pigment Red 122, manufactured by Dainichi Seika Co., Ltd.), 10 parts by mass of an anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 550 parts by mass of ion-exchanged water are mixed. Using a high-pressure impact disperser Ultimizer (HJP30006, manufactured by Sugino Machine Co., Ltd.), dispersion was performed at a pressure of 250 mPa for 1 hour to obtain a magenta colorant dispersion (M). The volume average particle diameter of the colorant in this colorant dispersion was 211 nm, and the solid content concentration was 23.8% by mass.

-Colorant dispersion (Y)-
100 parts by mass of yellow pigment (CI Pigment Yellow 74, manufactured by Clariant), 12 parts by mass of an anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 600 parts by mass of ion-exchanged water were mixed and subjected to high pressure impact. A yellow dispersion liquid (Y) was obtained by dispersing for 1 hour at a pressure of 250 mPa using a type disperser ultimateizer (HJP30006, manufactured by Sugino Machine Co., Ltd.). The volume average particle diameter of the colorant in this colorant dispersion was 238 nm, and the solid content concentration was 21.9% by mass.

-Colorant dispersion (K)-
Mixing 100 parts by mass of black pigment carbon black (R660R, manufactured by Cabot), 7 parts by mass of an anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 650 parts by mass of ion-exchanged water, high pressure impact disperser Alti Using a mizer (HJP30006, manufactured by Sugino Machine Co., Ltd.), the mixture was dispersed at a pressure of 250 mPa for 1 hour to obtain a black dispersion (K). The volume average particle size of the colorant in this colorant dispersion was 304 nm, and the solid content concentration was 21.2% by mass.

-Release agent dispersion (W1)-
After heating and melting 60 parts by weight of paraffin wax (HNP-9, manufactured by Nippon Seiki Co., Ltd.), 6 parts by weight of anionic surfactant Neogen RK (made by Daiichi Kogyo Co., Ltd.) and 200 parts by weight of ion-exchanged water at 110 ° C. Then, dispersion treatment was performed with a Menton Gorin high-pressure homogenizer (manufactured by Gorin) to obtain a release agent dispersion liquid (W1). The volume average particle size of the release agent in this release agent dispersion was 235 nm, and the solid content concentration was 24.2% by mass.

-Release agent dispersion (W2)-
Dispersion was performed under the same conditions as the release agent dispersion (W1) except that carnauba wax (manufactured by Riken Vitamin Co., Ltd.) was used, to obtain a release agent dispersion (W2). The volume average particle size of the release agent in this release agent dispersion was 200 nm, and the solid content concentration was 24 mass%.

-Release agent dispersion (W3)-
Dispersion was performed under the same conditions as the release agent dispersion (W1) except that synthetic ester wax and stearyl stearate (manufactured by NOF Corporation) were used, to obtain a release agent dispersion (W3). The volume average particle size of the release agent in this release agent dispersion was 190 nm, and the solid content concentration was 24% by mass.

-Release agent dispersion (W4)-
Dispersion was performed under the same conditions as the release agent dispersion (W1) except that zinc stearate (manufactured by NOF Corporation) was used to obtain a release agent dispersion (W4). The volume average particle size of the release agent in this release agent dispersion was 195 nm, and the solid content concentration was 24 mass%.

<Example 1>
(Production of toner)
35 parts by mass of crystalline polyester resin dispersion (A1), 230 parts by mass of amorphous polyester resin dispersion (B1), 45 parts by mass of cyan pigment dispersion (C) and 65 parts by mass of release agent dispersion (W1) After adding to a round stainless steel container and mixing, 2.5 parts by mass of a 10% nitric acid aqueous solution of polyaluminum chloride as a flocculant was added, and the temperature was raised to 44 ° C. to form core particles. Then, 130 parts by mass of amorphous polyester resin (B1) is added to form a shell, and the core particles are coated with shell particles, and then heated to 95 ° C. to further coalesce the particles. After maintaining at 95 ° C. for 1 hour, cooling, washing with alkali, acid and water were performed. This was then dried to obtain cyan toner particles having a volume average particle size of 6.1 μm and a GSDv of 1.28.

To 100 parts by mass of the obtained toner particles, 0.6 parts by mass of hydrophobized titanium oxide powder as an external additive and 0.8 parts by mass of hydrophobized silica powder were added and mixed with a Henschel mixer. An external toner was prepared.
The content of the crystalline polyester resin in the toner particles is 10.0% by mass. The amount of methanol-soluble component in the toner determined by the above method was 0.46%.

(Development of developer)
The surface of the ferrite particles (volume average particle size: 50 μm) was coated with methyl methacrylate resin (manufactured by Soken Chemical Co., Ltd., Mw: 82000) to prepare a carrier. 100 parts by mass of the carrier and 8 parts by mass of the externally added toner were mixed and mixed for 20 minutes with a V-type blender, and then the aggregate was removed by a vibrating screen having an aperture of 212 μm to obtain a developer.

(Evaluation of toner)
-Fixability-
The developer is put in a remodeling machine (modified so that an unfixed image can be output by removing the fixing device) of DocuCentreColor500 (manufactured by Fuji Xerox Co., Ltd.), and the applied toner amount is 0.1 g / m ² and 2 respectively. An unfixed image (50 mm × 50 mm) adjusted to be 5 g / m ² was produced. Subsequently, the unfixed images were sequentially fixed while increasing the surface temperature of the fixing member from 120 ° C. to 200 ° C. every 5 ° C. using an offline fixing bench.
Note that the contact time between the fixing member during fixing and the toner image on the paper was adjusted to 0.02 seconds, and ST paper manufactured by Fuji Xerox Co., Ltd. was used.

The image fixability is evaluated by bending a fixed image portion having a toner applied amount of 2.5 g / m ² and measuring the line width of white spots generated when the fixed image is destroyed. The temperature was defined as the minimum fixing temperature. Further, the hot offset temperature is set to the lowest temperature at which the white paper portion of the corresponding sheet is visually confirmed after one round of the fixing member surface after fixing the fixed image having the toner applied amount of 0.1 g / m ² . . Those not generated at 200 ° C. were set to> 200 ° C., and no further evaluation was performed. The fixable temperature range is the difference between the highest temperature at which hot offset does not occur and the lowest fixing temperature.

-Cover-
The developer is left unfixed for 24 hours in a high-temperature and high-humidity environment (temperature 28 ° C., humidity 85% RH), and then unfixed when the image having the applied toner amount of 2.5 g / m ² is developed and transferred. Judgment was made based on whether toner was confirmed in the background portion of the image. Those that could not be confirmed with a 25-fold magnifier were marked with ◎, those that could not be visually confirmed but could be confirmed with a 25-fold magnifier were marked with ○, and those that could be visually confirmed with x.

  For each evaluation, the minimum fixing temperature is 150 ° C. or lower, the hot offset is 180 ° C. or higher, the fixable temperature range is 50 ° C. or higher, and the fogging target is ○. It was considered that there was no problem to satisfy.

<Examples 2-11, Comparative Examples 1-3>
In the production of the toner of Example 1, the types and amounts of the crystalline polyester resin dispersion, the amorphous resin dispersion, the colorant dispersion, and the release agent dispersion were changed as shown in Table 1, respectively. In the same manner, toner B to toner N were prepared.
Each of these toners was evaluated in the same manner as in Example 1. The results are summarized in Table 2.

As shown in Table 2, in Examples using a toner having a methanol-soluble component content of 1% by mass or less and a crystalline polyester resin content in the range of 5 to 15% by mass, the offset generation temperature of the halftone varies. Therefore, a stable fixing temperature range can be secured.
On the other hand, in the comparative example, a problem occurred in any of hot offset, fixing temperature range, and fog at the time of development.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus of the present invention. It is a schematic block diagram which shows an example of the process cartridge of this invention.

Explanation of symbols

1Y, 1M, 1C, 1K, 107 photoconductor (image carrier)
2Y, 2M, 2C, 2K, 108 Charging roller 3Y, 3M, 3C, 3K Laser beam 3 Exposure device 4Y, 4M, 4C, 4K, 111 Developing device (developing means)
5Y, 5M, 5C, 5K Primary transfer rollers 6Y, 6M, 6C, 6K, 113 Photoconductor cleaning device (cleaning means)
8Y, 8M, 8C, 8K Toner cartridge 10Y, 10M, 10C, 10K Unit 20 Intermediate transfer belt 22 Drive roller 24 Support roller 26 Secondary transfer roller (transfer means)
28, 115 Fixing device (fixing means)
30 Intermediate transfer member cleaning device 112 Transfer device 116 Mounting rail 117 Opening 118 for static elimination exposure Opening 200 for exposure Process cartridge,
P, 300 Recording paper (transfer object)

Claims (8)

Amorphous polyester resin obtained from polycondensation of polyvalent aromatic carboxylic acid and polyhydric alcohol having bisphenol skeleton, Crystallinity obtained from polycondensation of polyhydric aliphatic carboxylic acid and polyhydric aliphatic alcohol Comprising polyester resin, mold release agent and colorant,
The content of the crystalline polyester resin is in the range of 5 to 15% by mass of the whole toner,
Add 100 g of tetrahydrofuran to 20 g of toner, heat and stir to 40 ° C., hold for 30 minutes, cool to room temperature, filter by heating with a glass filter, and stir methanol in a container containing 300 g of methanol. The filtrate was added dropwise over 10 minutes, and stirring was continued for 30 minutes after the addition. The filtrate was filtered, and the filtrate was desolvated, dried and weighed, and the mass was determined by dividing the mass by the original toner mass. The amount of the component dissolved in methanol is 1% by mass or less based on the whole toner,
Add 100 g of tetrahydrofuran to 20 g of the amorphous polyester resin, heat and stir at 40 ° C., hold for 30 minutes, cool to room temperature, filter by heating with a glass filter, and put methanol in a container containing 300 g of methanol. While stirring the filtrate, the filtrate was added dropwise over 10 minutes. After the addition, stirring was continued for 30 minutes, this was filtered, the filtrate was desolvated, dried and weighed, and the mass was determined based on the amorphous polyester resin. The amount of the component dissolved in methanol determined by dividing by the mass of the non-crystalline polyester resin is 1% by mass or less,
Add 100 g of tetrahydrofuran to 20 g of the crystalline polyester resin, heat and stir at 40 ° C., hold for 30 minutes, cool to room temperature, filter by heating with a glass filter, and put methanol in a container containing 300 g of methanol. While stirring, the filtrate was added dropwise over 10 minutes. After the addition, stirring was continued for 30 minutes, this was filtered, the filtrate was desolvated, dried and weighed, and the mass was the mass of the original crystalline polyester resin. The amount of the component dissolved in methanol determined by dividing by is 1% by mass or less based on the entire crystalline polyester resin,
An electrostatic charge image developing toner obtained by emulsifying and aggregating these resins. The electrostatic image developing toner according to claim 1, wherein each of the dispersions of the amorphous polyester resin and the crystalline polyester resin used for the emulsion aggregation contains an acid, a salt, or a base .   The electrostatic charge image developing toner according to claim 1, wherein the release agent is at least one selected from paraffin wax, carnauba wax, and ester wax.   An electrostatic image developer, comprising a toner, wherein the toner is the electrostatic image developing toner according to claim 1.   A toner cartridge containing at least toner, wherein the toner is the electrostatic image developing toner according to claim 1.   5. A process cartridge comprising at least a developer holder and containing the electrostatic charge image developer according to claim 4.   An image carrier, a developing unit that develops an electrostatic image formed on the image carrier as a toner image with a developer, and a transfer unit that transfers the toner image formed on the image carrier onto a transfer target An image forming apparatus comprising: a fixing unit configured to fix a toner image transferred onto a transfer target; and the developer is the electrostatic charge image developer according to claim 4.   A developing process for developing the electrostatic image formed on the image carrier as a toner image with a developer; a transfer process for transferring the toner image formed on the image carrier onto the transfer body; And a fixing step for fixing the toner image transferred to the toner image, wherein the developer is the electrostatic charge image developer according to claim 4.

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