JP2010072481A - Toner for electrostatic charge image development and method for manufacturing the same, toner cartridge, process cartridge, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner for electrostatic charge image development, where compounding of the toner structural components is improved and moreover, impurities are reduced. <P>SOLUTION: The toner for electrostatic charge image development contains a binder resin, a colorant and a biodegradable dispersant. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

  A so-called xerographic image forming apparatus includes an electrophotographic photosensitive member (hereinafter sometimes referred to as “photosensitive member”), a charging device, an exposure device, a developing device, and a transfer device, and an electrophotographic process using them. Image formation is performed. In recent years, xerographic image forming apparatuses have been further improved in speed, image quality, and lifetime due to technological progress of each member and system. Further, while consumables such as toner are required to have high functionality, those composed of structures, materials, and the like with a low environmental load have been demanded.

  As a material with little environmental load, a material with high biodegradability is mentioned, for example. In particular, in recent years, in order to achieve high functionality, there has been an active study of producing toner by a wet manufacturing method, but in order to reduce the environmental impact of the material that flows into the waste water at the time of production, In particular, there is a demand for safe materials with a small amount of outflow and environmental loads.

These degradable material studies have been used in various studies (see Patent Documents 1, 2, and 3). In Patent Document 1, a charge control agent contains a sulfate ester type surfactant. In Patent Document 2, a biodegradable resin having a low melting point is contained. Patent Document 3 is also a toner made of a degradable new resin. In addition, an attempt to reduce the environmental load by achieving a so-called long life by investigating an electrophotographic photoreceptor having a protective layer is also active (see Patent Document 4).
On the other hand, Patent Document 5 discloses charge control using an aromatic carboxylic acid having at least two carboxyl groups capable of forming an acid anhydride in the molecule and having an aromatic ring having 12 to 20 carbon atoms as an active ingredient. Agents are disclosed.
JP 2000-347461 A JP 2007-114607 A JP 2005-154698 A JP-A-9-68826 JP 7-43949 A

  An object of the present invention is to provide a toner for developing an electrostatic image with improved blending of toner constituents and less impurities.

The above-mentioned subject is achieved by the following present invention.
That is, the invention according to claim 1
An electrostatic charge image developing toner comprising a binder resin, a colorant, and a biodegradable dispersant.

The invention according to claim 2
The electrostatic charge image developing toner according to claim 1, wherein the biodegradable dispersant contains an ether carboxylic acid compound.

The invention according to claim 3
The electrostatic charge image developing toner according to claim 2, wherein the ether carboxylic acid compound includes an alkyl ether carboxylic acid compound.

The invention according to claim 4
The electrostatic charge image developing toner according to claim 2, wherein the biodegradable dispersant contains a sulfate ester compound in addition to the ether carboxylic acid compound.

The invention according to claim 5
A resin particle dispersion adjusting step of adjusting a resin particle dispersion in which resin particles are dispersed;
A colorant particle dispersion adjusting step for adjusting a colorant particle dispersion in which the colorant particles are dispersed;
A mixed solution adjusting step of mixing the resin particle dispersion and the colorant particle dispersion to adjust a mixed solution containing the resin particles and the colorant particles;
An aggregated particle adjusting step of adjusting aggregated particles in which the resin particles and the colorant particles are aggregated;
A fusion and coalescence step of fusing and coalescing the aggregated particle dispersion in which the aggregated particles are dispersed above the glass transition temperature of the resin particles,
At least one of the resin particle dispersion adjustment step, the colorant particle dispersion adjustment step, and the mixed solution adjustment step includes a step of adding a biodegradable dispersant. A toner manufacturing method.

The invention according to claim 6
The method for producing a toner for developing an electrostatic charge image according to claim 5, wherein the biodegradable dispersant contains an ether carboxylic acid compound.

The invention according to claim 7 provides:
The method for producing a toner for developing an electrostatic charge image according to claim 6, wherein the ether carboxylic acid compound contains an alkyl ether carboxylic acid compound.

The invention according to claim 8 provides:
The method for producing a toner for developing an electrostatic charge image according to claim 6, wherein the biodegradable dispersant contains a sulfate ester compound in addition to the ether carboxylic acid compound.

The invention according to claim 9 is:
An electrostatic charge image developing developer comprising the electrostatic charge image developing toner according to any one of claims 1 to 4.

The invention according to claim 10 is:
Toner is stored in the image forming apparatus provided with the developing means, and is supplied to the developing means.
The toner is a toner cartridge which is the electrostatic charge image developing toner according to any one of claims 1 to 4.

The invention according to claim 11 is:
A process cartridge comprising a developer holder and containing the developer for developing an electrostatic charge image according to claim 9.

The invention according to claim 12
A latent image carrier,
An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the latent image holding member;
Developing means for developing the electrostatic latent image with a developer containing toner to form a toner image;
Transfer means for transferring the toner image formed on the latent image holding member to the surface of a recording medium;
Toner removing means for removing residual toner remaining on the surface of the latent image holding member,
The image forming apparatus according to claim 9, wherein the developer is a developer for developing an electrostatic charge image.

The invention according to claim 13 is:
13. The image forming apparatus according to claim 12, further comprising: a residual toner collecting / supplying unit that collects the residual toner removed by the toner removing unit and supplies the collected residual toner to the developing unit.

The invention according to claim 14 is:
14. The image forming apparatus according to claim 12, wherein the layer constituting the outermost surface of the latent image holding member includes a resin having a three-dimensional crosslinked structure.

According to the first aspect of the present invention, compared with the case where no biodegradable dispersant is contained, the blending of the toner constituents is improved and the impurities are reduced.
According to the second aspect of the present invention, as compared with the case where the biodegradable dispersant does not contain an ether carboxylic acid compound, the blending of the toner constituent components is further improved and the impurities are reduced.
According to the third aspect of the present invention, as compared with the case where the ether carboxylic acid compound does not contain the alkyl ether carboxylic acid compound, the blending of the toner constituent components is further improved and the impurities are reduced.
According to the fourth aspect of the invention, compared with the case where no sulfate ester compound is used in combination, the blending of the toner constituent components is further improved and the impurities are reduced.

According to the fifth aspect of the present invention, compared to a case where the step of adding a biodegradable dispersant is not included, a toner with improved blending of toner constituents and less impurities can be obtained.
According to the sixth aspect of the present invention, compared with the case where the biodegradable dispersant does not contain an ether carboxylic acid compound, the blending of the toner constituent components is further improved and the impurities are reduced.
According to the seventh aspect of the present invention, compared with the case where the ether carboxylic acid compound does not contain an alkyl ether carboxylic acid compound, the blending of the toner constituent components is further improved and the impurities are reduced.
According to the eighth aspect of the present invention, compared with the case where the sulfate ester compound is not used in combination, the blending of the toner constituent components is further improved and the impurities are reduced.

According to the ninth aspect of the invention, the toner is less likely to break than when the toner does not contain a biodegradable dispersant.
According to the tenth aspect of the present invention, the toner is less likely to break than when the toner does not contain a biodegradable dispersant.
According to the eleventh aspect of the invention, the toner is less likely to break than when the toner does not contain a biodegradable dispersant.
According to the twelfth aspect of the present invention, compared to a case where the toner does not contain a biodegradable dispersant, the toner is not easily broken and a high-quality image is formed over a long period of time.

According to the thirteenth aspect of the invention, even if the configuration includes the residual toner collecting and supplying means, the toner is hardly broken and a high-quality image is formed over a long period of time.
According to the fourteenth aspect of the present invention, even when a latent image carrier having a high surface altitude is used, the toner is hardly broken and a high-quality image is formed over a long period of time.

Hereinafter, the present invention will be described in detail.
<Toner for electrostatic image latent image>
The electrostatic image developing toner of the present embodiment (hereinafter sometimes simply referred to as “toner”) includes a binder resin, a colorant, and a biodegradable dispersant (hereinafter referred to as “biodegradable dispersant”). In some cases) and may contain other components such as a release agent, if necessary.

When the toner according to the exemplary embodiment has the above-described configuration, the toner components are blended uniformly and impurities are reduced. The reason is not clear, but is presumed as follows.
If the toner contains a biodegradable dispersant, the dispersibility and dispersion stability of each component (binder resin, colorant, release agent, etc.) will be improved during the toner manufacturing process. Even in the applied toner, uneven distribution of each component does not easily occur. In other words, by including a biodegradable dispersant in the toner, the toner constituents are uniformly blended, so that the durability of the toner is improved, and the properties such as the electrical properties of the toner are improved. It is estimated that a high-quality image is formed. In addition, since the toner contains a biodegradable dispersant and the toner constituents are uniformly blended, the surface exposure of components (eg, a colorant and a release agent) excluding the binder resin is also suppressed, and the toner It is presumed that the characteristics and image quality will be good.

  Further, since the added biodegradable dispersant is decomposed during the production process of the toner, the amount of the biodegradable dispersant remaining in the produced toner is small. Therefore, compared to the case where a large amount of the dispersant remains in the toner as in the case of using another dispersant, the toner has fewer impurities, so the durability of the toner, the electrical characteristics, the image quality of the formed image, etc. Is estimated to be good. Conversely, even when a large amount of dispersant is added compared to the case where other dispersants are used, the amount of the dispersant (that is, impurities) remaining in the toner is small, so that the toner characteristics and image quality are good. Presumed to be.

  In addition, it is presumed that the decomposition product of the biodegradable dispersant remaining inside the toner suppresses an adverse effect on the toner due to the ionic impurity by coordinating the ionic impurity. Therefore, in the present embodiment, pigments with a large amount of ionic impurities that have been difficult to use in the conventional water-based toner manufacturing method (for example, Ca, Mg, Fe, Ba, which are mixed in the pigment manufacturing process or the sulfonation process) are used. In the case of using divalent or higher-valent metal ions such as Al and Ni, chloride ions, and sulfate ions, etc., the toner becomes a toner in which uneven distribution of the constituent components is suppressed, and the characteristics and image quality of the toner are improved. Guessed.

  In addition, since the biodegradable dispersant is decomposed during the toner production process, the waste water generated by the toner production contains a lot of decomposition products generated after the biodegradable dispersant is decomposed. Since the content of itself is small, it is estimated that the wastewater treatment cost is reduced.

  In addition, since the biodegradable dispersant is easily decomposed, it is assumed that the decomposition of the resin is suppressed by self-degrading the biodegradable dispersant when the resin is easily decomposed in the toner manufacturing process. . As a result, it is presumed that the toner has good durability and few impurities.

  Hereinafter, each composition component will be described.

-Biodegradable dispersant-
In this embodiment, the biodegradable dispersant is a biological substance such as a hydrolysis or a microorganism in which a bond of a functional group is cleaved, and a reaction in which water molecules are divided into H ⁺ and OH ⁻ is added to the cleavage site. This refers to biodegradation that is converted into carbon dioxide or water by reaction.

Among the biodegradable dispersants, ether carboxylic acids, derivatives thereof, and salts thereof (hereinafter sometimes referred to as “ether carboxylic acid compounds”) are preferable.
By using the above compound as a biodegradable dispersant, the uniformity of the blending of toner constituents is further increased and impurities are reduced. The reason is not clear, but is presumed as follows.

  The ether carboxylic acid compound has a chelating ability (ability to form a coordinate bond) between the oxygen atom of the ether contained in the ether carboxylic acid compound and the carboxyl group contained in the ionic impurity due to its molecular structure. That is, the ether carboxylic acid compound is dissolved in the aqueous solvent while coordinating the ionic impurities in the toner, so that it is estimated that the ether carboxylic acid compound is discharged to the surface or outside of the toner in the toner manufacturing process, and the impurities in the toner are reduced.

  Further, since the ether carboxylic acid compound exhibits hydrolyzability, for example, when toner is prepared by a wet process, the ether carboxylic acid compound is gradually decomposed by optimizing the conditions during the preparation of the toner, so that the water phase is separated from the toner surface. Even when the toner cleaning process is simplified or when a large amount of biodegradable dispersant is contained, the ether carboxylic acid compound hardly remains in the toner, and the electrical characteristics and the like are maintained over a long period of time. Toner is obtained.

  Specific examples of ether carboxylic acid compounds include alkyl ether carboxylic acid compounds (alkyl ether carboxylic acids, derivatives thereof, and salts thereof), and hydroxy ether carboxylic acid compounds (hydroxy ether carboxylic acids, derivatives thereof, and Among these, alkyl ether carboxylic acid compounds are preferred from the viewpoint of improving the electrical property environment difference when they remain in the toner in a trace amount and improving the storage stability of the toner due to the hygroscopicity of the hydroxyl group.

As the alkyl ether carboxylic acid, a linear or branched alkyl group having 4 to 22 carbon atoms is preferable. More specifically, for example, propyl ether acetic acid, octyl ether acetic acid, decyl ether acetic acid, Examples include lauryl ether acetic acid and myristyl ether acetic acid.
Specific examples of the alkyl ether carboxylic acid derivative include, for example, propyl ether acetate, propyl ether acetate, octyl ether acetate, octyl ether acetate, decyl ether acetate, decyl ether acetate, lauryl ether acetate. Lauryl ether acetic acid amide, myristyl ether acetic acid ester, myristyl ether acetic acid amide and the like.

Hydroxy ether carboxylic acid is an ether carboxylic acid that is preferably used for further improving the dispersibility of the pigment and the release agent, and hydroxy ether carboxylic acid containing an alkyl group having 4 to 22 carbon atoms is preferably used.
More specifically, examples of the hydroxy ether carboxylic acid include hydroxy ethyl ether acetic acid, hydroxy propyl ether acetic acid, hydroxy octyl ether acetic acid, hydroxy decyl ether acetic acid, hydroxy lauryl ether acetic acid, hydroxymyristyl ether acetic acid and the like.
Specifically, the derivative of the hydroxy ether carboxylic acid is preferably, for example, a linear or branched alkyl group having 4 to 22 carbon atoms, a hydroxy ether carboxylic acid ester containing an alkenyl group, or a hydroxy ether carboxylic acid amide. Hydroxyethyl ether acetate, hydroxyethyl ether acetate, hydroxypropyl ether acetate, hydroxypropyl ether acetate, hydroxy octyl ether acetate, hydroxy octyl ether acetate, hydroxydecyl ether acetate, hydroxy lauryl ether acetate, hydroxy lauryl Examples include ether acetates and hydroxymyristyl ether acetates.
Specific examples of salts of alkyl ether carboxylic acid, hydroxy ether carboxylic acid, or derivatives thereof include, for example, sodium salt, potassium salt, magnesium salt, ammonium salt, lower alkanolamine (mono, di, triethanolamine). Examples include salt.

The biodegradable dispersant is desirably used in combination with a sulfate ester compound in addition to the ether carboxylic acid compound. With the above combination, the ether carboxylic acid compound acts more uniformly in the particles, thereby reducing impurities in the toner. Further, the toner constituents are blended uniformly.
In addition to the above-described effects due to the hydrolyzability, the sulfate ester compound has the effect of acting as a dispersion stabilizer. For example, when a toner is produced by an agglomeration and coalescence method, colorant particles or Prevents release agent particles and the like from agglomerating rapidly and being unevenly distributed in the toner. Therefore, when used in combination with an ether carboxylic acid compound, the toner structure is formed while stably dispersing the particles of the colorant and the release agent that are difficult to disperse and effectively removing the impurities contained in them. It is presumed that a toner that maintains electrical characteristics and the like can be obtained.

Specific examples of the sulfate ester compound include higher alcohol sulfate compounds (higher alcohol sulfate esters and salts thereof), higher alkyl ether sulfate compounds (higher alkyl ether sulfate esters and salts thereof), and And sulfated oil / sulfated fatty acid ester compounds (sulfated oil / sulfated fatty acid ester, derivatives thereof, and salts thereof).
Examples of the higher alcohol sulfate include sulfate having an alkyl group having 12 to 30 carbon atoms or an alkoxy group. Specifically, for example, sodium lauryl sulfate, sodium tridecyl sulfate, sodium myristyl sulfate, Sodium cetyl sulfate, sodium stearyl sulfate, sodium nonadecyl sulfate, sodium oleyl sulfate, sodium behenyl sulfate and the like can be used, and sodium lauryl sulfate is particularly preferable.

  Examples of the higher alkyl ether sulfate include sulfate having an alkyl ether group having 12 to 30 carbon atoms. Specifically, for example, lauryl ether sulfate, tridecyl ether sulfate, myristyl ether sulfate, cetyl Ether sulfates, stearyl ether sulfates, nonadecyl ether sulfates, oleyl ether sulfates, behenyl ether sulfates, etc. can be used, especially lauryl sulfates, and salts of these sulfates (eg, sodium, potassium, lithium, or A salt with calcium) is preferably used.

Specific examples of sulfated oils and sulfated fatty acid esters include olive oil, cottonseed oil, peanut oil, linseed oil, rapeseed oil from old and new plants, sunflower oil from old and new plants, castor oil, beef tallow and There are sulfated products of fish oil. The use of sulfated triolein, olive oil or fish oil is particularly preferred.
Specific examples of salts of higher alcohol sulfates, higher alkyl ether sulfates, sulfated oils and sulfated fatty acid esters include sodium salts, potassium, lithium, magnesium salts, ammonium salts, lower alkanolamines (mono, Di, triethanolamine) salts and the like.

  The total content of the biodegradable dispersant in the toner is preferably from 0.5% by weight to 5% by weight, more preferably from 0.7% by weight to 4% by weight, and more preferably from 1% by weight to 3.5% by weight. % Or less is more preferable. Since the biodegradable dispersant is decomposed in the toner manufacturing process, the content of the biodegradable dispersant remaining in the toner can be kept low. For this reason, deterioration of toner characteristics and image quality due to the remaining dispersant is suppressed.

  When an ether carboxylic acid compound is used as the biodegradable dispersant, the content of the ether carboxylic acid compound in the toner is preferably 0.2% by mass or more and 2.5% by mass or less, and more preferably 0.4% by mass or more and 2.0% by mass. More preferably, it is 0.5 mass% or less, and more preferably 0.5 mass% or more and 1.8 mass% or less.

  When an ether carboxylic acid compound and a sulfate ester compound are used in combination as a biodegradable dispersant, the ether carboxylic acid compound content in the toner is 0.5 to 2 times the sulfate ester content in the toner. Preferably, it is 0.5 to 1.7 times, more preferably 0.7 to 1.5 times.

Identification and content measurement of the biodegradable dispersant contained in the toner are measured as follows.
Specifically, first, trimethylsilylation of the toner is performed as follows. 1 g of toner is dispersed in 5 ml of acetone (solvent), 25 ml of ion-exchanged water is added and mixed, and solid-liquid separation is performed. 10 ml of trimethylchlorosilane was added to the obtained solution and stirred at room temperature (25 ° C.) for 3 hours to perform a coupling reaction (trimethylsilylation treatment), which is used as a measurement sample.
Next, the measurement sample is measured under the following conditions using the following pyrolysis gas chromatography mass spectrometer, and the biodegradable dispersant is identified and the content is measured.
・ Model: Hitachi N-5000 (quadrupole type)
Column: GLscience DB-1 (0.25 mm × 30 m × 0.25 μm)
-Curie Point Pyrolyzer measurement method (400 ° C)
・ Temperature raising program: Hold at 60 ° C. for 5 minutes, then heat up at 5 ° C./minute and hold at 200 ° C. for 5 minutes. Measurement is performed with a device (XRF-1500 manufactured by XRF Shimadzu Corp.) under a vacuum (degree of vacuum 10 to 100 Pa) atmosphere under an acceleration voltage of 40 kV, a current value of 70 mV, and a measurement time of 15 minutes, and a known concentration The abundance is identified by comparison with the peak intensity of the sulfate-containing sample.

-Binder resin-
In the toner of this embodiment, it is preferable to use a crystalline resin as a binder resin. Moreover, it is particularly preferable to use an amorphous resin in combination as necessary.
In the present embodiment, “crystalline resin” means a resin having a clear endothermic peak (a peak where the half-value width of the endothermic peak is 10 ° C. or less) in differential scanning calorimetry (DSC). "Crystalline resin" means a resin that does not have the above-mentioned clear peak. In addition, regardless of whether the resin is a crystalline resin or an amorphous resin, the weight average molecular weight of the binder resin is particularly preferably 10,000 or more, and the weight average molecular weight is usually preferably in the range of 15000 to 50000.
As the crystalline resin, for example, a polyester resin, a crystalline vinyl resin, or the like can be used. As the amorphous resin, for example, a polyester resin, a polyurethane resin, an epoxy resin, a polyol resin, or the like is used. Hereinafter, the binder resin used in the present invention will be described separately for a crystalline resin and an amorphous resin.

(Crystalline resin)
The content of the crystalline resin contained in the toner particles is preferably in the range of 2% by mass to 30% by mass, and more preferably in the range of 3% by mass to 15% by mass. If the content of the crystalline resin is less than 2% by weight, fixing in a low temperature region may be difficult. Further, if the content of the crystalline resin exceeds 30% by mass, gloss unevenness is likely to occur or filming is likely to occur particularly when fixing is performed in a middle temperature range or a high temperature range. The toner of the present embodiment preferably has an external additive added as will be described later. In this specification, the toner before the external additive is added may be referred to as “toner particles”.

As melting | fusing point of crystalline resin, the range of 45 to 110 degreeC is preferable, The range of 50 to 100 degreeC is more preferable, The range of 55 to 90 degreeC is still more preferable.
When the melting point is lower than 45 ° C., it becomes difficult to store the toner, and when it exceeds 110 ° C., fixing in a low temperature range (hereinafter sometimes referred to as “low temperature fixability”) may be difficult. In addition, melting | fusing point of crystalline resin means what was calculated | required by the method based on ASTMD3418-8.

  Further, the number average molecular weight (Mn) of the crystalline resin is preferably 5000 or more, and more preferably 7000 or more. If the number average molecular weight (Mn) is less than 7000, the toner may permeate into the surface of a recording medium such as paper at the time of fixing to cause uneven fixing, or the resistance to bending of the fixed image may be reduced. .

  As described above, crystalline polyester resin, crystalline vinyl resin, etc. are used as the crystalline resin, but it is easy to obtain a melting point that satisfies the above-mentioned range, such as adhesion to paper and chargeability during fixing. In view of the above, it is preferable to use a crystalline polyester resin. In particular, an aliphatic crystalline polyester resin is more preferable because a resin having a desired melting point is easily obtained.

  Examples of the crystalline vinyl resin include amyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, and (meth) acrylic. Decyl acid, undecyl (meth) acrylate, tridecyl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, oleyl (meth) acrylate, (meth) acrylic acid Examples thereof include vinyl resins using long-chain alkyl such as behenyl and alkenyl (meth) acrylic acid esters. In the present specification, the description “(meth) acryl” means that both “acryl” and “methacryl” are included.

On the other hand, the crystalline polyester resin is synthesized from a carboxylic acid (dicarboxylic acid) component and an alcohol (diol) component.
Hereinafter, the carboxylic acid component and the alcohol component will be described in more detail. In the present specification, the “crystalline polyester resin” also means a copolymer obtained by copolymerizing other components in a proportion of 50% by mass or less with respect to the main chain of the crystalline polyester resin.

  The carboxylic acid component is preferably an aliphatic dicarboxylic acid, and particularly preferably a linear carboxylic acid. For example, succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,11-undecanedicarboxylic acid Acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc., or lower alkyl esters thereof, Acid anhydrides can be mentioned but are not limited to these.

  The carboxylic acid component preferably contains constituent components such as a dicarboxylic acid component having a double bond and a dicarboxylic acid component having a sulfonic acid group in addition to the aliphatic dicarboxylic acid component described above. The dicarboxylic acid component having a double bond includes a component derived from a lower alkyl ester or acid anhydride of a dicarboxylic acid having a double bond, in addition to a component derived from a dicarboxylic acid having a double bond. Is also included. The dicarboxylic acid component having a sulfonic acid group includes a component derived from a dicarboxylic acid having a sulfonic acid group, a lower alkyl ester of a dicarboxylic acid having a sulfonic acid group, or an acid anhydride. Is also included.

  The dicarboxylic acid having a double bond is preferably used in order to prevent hot offset at the time of fixing because the entire resin can be crosslinked using the double bond. Examples of the dicarboxylic acid include, but are not limited to, fumaric acid, maleic acid, 3-hexenedioic acid, and 3-octenedioic acid. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned. Among these, fumaric acid, maleic acid and the like are preferable in terms of cost.

  The dicarboxylic acid having a sulfonic acid group is effective in improving the dispersion of a coloring material such as a pigment. Further, if the entire resin is emulsified or suspended in water to produce particles, if there are sulfonic acid groups, as described later, the resin may be emulsified or suspended without using a surfactant. Examples of the dicarboxylic acid having a sulfonic acid 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. Among these, 5-sulfoisophthalic acid sodium salt and the like are preferable in terms of cost.

  The content of the carboxylic acid component other than these aliphatic dicarboxylic acid components (dicarboxylic acid component having a double bond and / or dicarboxylic acid component having a sulfonic acid group) in the carboxylic acid component is 1 component mol% or more and 20 Constituent mol% is preferable, and 2 constituent mol% or more and 10 constituent mol% is more preferable.

When the content is less than 1 mol%, the dispersibility of the pigment in the toner base particles may deteriorate if a pigment is used as the colorant.
Further, when a toner is prepared using an emulsion polymerization aggregation method, the emulsion particle size in the dispersion becomes large, and it may be difficult to adjust the toner diameter by aggregation. On the other hand, when it exceeds 20 constituent mol%, the crystallinity of the crystalline polyester resin is lowered, the melting point is lowered, and the storage stability of the image may be deteriorated. Further, when a toner is prepared by using an emulsion polymerization aggregation method, the emulsion particle size in the dispersion is too small to dissolve in water, and latex may not be generated. In the present invention, “constituent mol%” refers to a percentage when each constituent component (carboxylic acid component, alcohol component) in the polyester resin is 1 unit (mol).

  On the other hand, the alcohol component is preferably an aliphatic diol, such as 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, 1,20-eicosanediol and the like are exemplified, but not limited thereto.

  The alcohol component preferably has an aliphatic diol component content of 80 constituent mol% or more, and includes other components as necessary. As the alcohol component, the content of the aliphatic diol component is more preferably 90 constituent mol% or more.

  When the content is less than 80 mol%, the crystallinity of the polyester resin is lowered and the melting point is lowered, so that toner blocking resistance, image storage stability and low-temperature fixability may be deteriorated. On the other hand, examples of other components included as necessary include diol components having a double bond and diol components having a sulfonic acid group.

  Examples of the diol having a double bond include 2-butene-1,4-diol, 3-butene-1,6-diol, 4-butene-1,8-diol, and the like. On the other hand, examples of the diol having a sulfonic acid group include 1,4-dihydroxy-2-sulfonic acid benzene sodium salt, 1,3-dihydroxymethyl-5-sulfonic acid benzene sodium salt, and 2-sulfo-1,4. -Butanediol sodium salt and the like.

  In the case of adding an alcohol component other than these linear aliphatic diol components (a diol component having a double bond and / or a diol component having a sulfonic acid group), the content in the alcohol component is one component mole. % Or more and 20 component mol% is preferable, and 2 component mol% or more and 10 component mol% is more preferable. When the content is less than 1 constituent mol%, pigment dispersion may be poor, the emulsified particle diameter may be large, and adjustment of the toner diameter by aggregation may be difficult. On the other hand, if it exceeds 20 component mol%, the crystallinity of the polyester resin is lowered, the melting point is lowered, the image storage stability is deteriorated, or the emulsion particle size is too small to dissolve in water, and no latex is produced. There is a case.

  The method for producing the crystalline polyester resin is not particularly limited and can be produced by a general polyester polymerization method in which a carboxylic acid component and an alcohol component are reacted. Examples thereof include direct polycondensation and transesterification. Produced separately depending on the type of monomer. The molar ratio (acid component / alcohol component) when the acid component reacts with the alcohol component varies depending on the reaction conditions and the like, and cannot be generally stated, but is usually about 1/1.

  The crystalline polyester resin can be produced at a polymerization temperature of 180 ° C. or higher and 230 ° C. or lower. The reaction system is reduced in pressure as necessary, and the reaction is carried out while removing 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. If a monomer with poor compatibility is present in the copolymerization reaction, the monomer with poor compatibility and the monomer and the carboxylic acid component or alcohol component to be polycondensed are condensed in advance and then polycondensed together with the main component. Good.

  Examples of the catalyst 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, Examples include metal compounds such as germanium; phosphorous acid compounds, phosphoric acid compounds, and amine compounds. Specific examples include the following compounds.

  For example, sodium acetate, sodium carbonate, lithium acetate, calcium acetate, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate, titanium tetraethoxide, titanium tetrapropoxide, titanium tetraisopropoxide, titanium tetra Butoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium tetrabutoxide, zirconium naphthenate, zirconyl carbonate, zirconyl acetate, zirconyl acetate , Zirconyl octylate, germanium oxide, triphenyl phosphite, tris (2,4-di-t-butylphenyl) phosphite Ethyltriphenylphosphonium bromide, triethylamine, compounds such as triphenyl amine.

  Among the catalysts containing metal elements capable of taking the valences of 2 or more listed above, calcium acetate is preferred from the viewpoint that it is easier to achieve both low-temperature fixability and gloss unevenness suppressing effect at a high level. It is preferable to use manganese acetate.

In addition to the polymerizable monomer described above, a compound having a shorter chain alkyl group, alkenyl group, aromatic ring or the like is also used for the purpose of adjusting the melting point, molecular weight, etc. of the crystalline resin.
Specific examples include, for example, dicarboxylic acids, alkyldicarboxylic acids such as succinic acid, malonic acid, and oxalic acid, and phthalic acid, isophthalic acid, terephthalic acid, homophthalic acid, 4,4′-bibenzoic acid, 2, Aromatic dicarboxylic acids such as 6-naphthalenedicarboxylic acid and 1,4-naphthalenedicarboxylic acid, nitrogen-containing aromatic dicarboxylic acids such as dipicolinic acid, dinicotinic acid, quinolinic acid, and 2,3-pyrazinedicarboxylic acid, and diols In the case of short chain alkyl diols such as succinic acid, malonic acid, acetone dicarboxylic acid, diglycolic acid, etc., and in the case of short chain alkyl vinyl polymerizable monomers, methyl (meth) acrylate, ( Short chain alkyls such as ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and alkenyl (Meth) acrylic acid esters, vinyl nitriles such as acrylonitrile and methacrylonitrile, vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether, vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketones, ethylene, propylene, butadiene And olefins such as isoprene. These polymerizable monomers may be used individually by 1 type, and may use 2 or more types together.

(Non-crystalline resin)
In the toner of the present embodiment, an amorphous resin may be used in combination with a crystalline resin as a binder resin.
The molecular weight of the amorphous resin to be used is not particularly limited, but when the toner is produced by using an emulsion polymerization aggregation method described later, an amorphous resin having a high weight average molecular weight (Mw) (high It is preferable to use a non-crystalline resin (low molecular weight component) having a low molecular weight component and a molecular weight component.

  In this case, Mw of the high molecular weight component is preferably 30000 or more and 300000 or less, more preferably 30000 or more and 200000 or less, and particularly preferably 35000 or more and 150,000 or less. By controlling the Mw of the high molecular weight component within the above range, it is more efficiently compatible with the crystalline resin, and further, separation from the crystalline resin once compatible is suppressed.

On the other hand, the Mw of the low molecular weight component is preferably 8000 or more and 25000 or less, more preferably 8000 or more and 22000 or less, and particularly preferably 9000 or more and 20000 or less.
By controlling the Mw of the high molecular weight component within the above range, the inclusion of the high molecular weight component in the toner particles is improved when the aggregated particles obtained by aggregating the raw material components by the emulsion polymerization aggregation method are heated and fused. The exposure of the crystalline resin to the toner particle surface is prevented.

As described above, when the high molecular weight component and the low molecular weight component are mixed and used, the blending ratio of both is preferably in the range of high molecular weight component / low molecular weight component = 35/65 to 95/5, and 40/60 The range of thru | or 90/10 is more preferable, and the range of 50/50 thru | or 85/15 is still more preferable.
The high molecular weight component preferably contains alkenyl succinic acid or its anhydride and trimellitic acid or its anhydride as its constituent monomers. Alkenyl succinic acid or its anhydride is more easily compatible with crystalline polyester resin due to the presence of highly hydrophobic alkenyl groups.

  In the present embodiment, the molecular weight distribution uses Tosoh Corporation HLC-8120GPC, SC-8020 apparatus, the column uses TSK gei, SuperHM-H (6.0 mm ID × 15 cm × 2), and THF (tetrahydrofuran) as an eluent. ). The measurement conditions were a sample concentration of 0.5% and a flow rate of 0.6 ml / min. Sample injection volume 10 μl, measurement temperature 40 ° C., calibration curve is A-500, F-1, F-10, F-80, F-380, A-2500, F-4, F-40, F-128, Made from 10 samples of F-700. The data collection interval in sample analysis was 300 ms.

  Examples of the alkenyl succinic acid component include n-dodecenyl succinic acid, isododecenyl succinic acid, n-octenyl succinic acid, acid anhydrides, acid chlorides thereof, and lower alkyl esters having 1 to 3 carbon atoms. By containing a trivalent or higher polyvalent carboxylic acid, the polymer chain takes a crosslinked structure. By taking a cross-linked structure, an effect of fixing the crystalline polyester resin once compatible and making it difficult to separate is obtained. Examples of trivalent or higher polyvalent carboxylic acids include hemimellitic acid, trimellitic acid, trimesic acid, merophanic acid, planitic acid, pyromellitic acid, merit acid, 1,2,3,4-butanetetracarboxylic acid and These acid anhydrides, acid chlorides and lower alkyl esters having 1 to 3 carbon atoms can be mentioned.

There is no restriction | limiting in particular in the manufacturing method of an amorphous polyester resin, It manufactures with the above-mentioned general polyester polymerization method. As the carboxylic acid component used for the synthesis of the amorphous polyester resin, various dicarboxylic acids mentioned for the crystalline polyester resin are used.
As the alcohol component, various diols used for the synthesis of the amorphous polyester resin are used. In addition to the aliphatic diols mentioned for the crystalline polyester resin, for example, bisphenol A, bisphenol A ethylene oxide adduct, bisphenol A Propylene oxide adducts, hydrogenated bisphenol A, bisphenol S, bisphenol S ethylene oxide adducts, bisphenol S propylene oxide adducts, and the like are used. Furthermore, it is particularly preferable to use bisphenol S derivatives such as bisphenol S, bisphenol S ethylene oxide adduct, and bisphenol S propylene oxide adduct from the viewpoints of toner manufacturability, heat resistance, and transparency. Moreover, both a carboxylic acid component and an alcohol component may contain a plurality of components, and in particular, bisphenol S has an effect of improving heat resistance.

(Binder resin crosslinking treatment, etc.)
Next, an amorphous resin used as a binder resin, a crosslinking treatment of a crystalline resin used as necessary, a copolymer component used in the synthesis of the binder resin, and the like will be described.
In the synthesis of the binder resin, other components can be copolymerized and a compound having a hydrophilic polar group is used. As a specific example, when the binder resin is a polyester resin, for example, dicarboxylic acid compounds in which an aromatic ring such as sulfonyl-terephthalic acid sodium salt or 3-sulfonylisophthalic acid sodium salt is directly substituted are mentioned. When the binder resin is a vinyl resin, for example, unsaturated aliphatic carboxylic acids such as (meth) acrylic acid and itaconic acid, glycerin mono (meth) acrylate, fatty acid-modified glycidyl (meth) acrylate, and zinc mono (meth) acrylate , Zinc di (meth) acrylate, 2-hydroxyethyl (meth) acrylate, polyethylene glycol (meth) acrylate, esters of (meth) acrylic acid and alcohols such as polypropylene glycol (meth) acrylate, ortho, meta, para Examples thereof include styrene derivatives having a sulfonyl group at any position, sulfonyl group-substituted aromatic vinyls such as sulfonyl group-containing vinyl naphthalene, and the like.

In addition, a crosslinking agent may be added to the binder resin as necessary for the purpose of preventing uneven glossiness, uneven color development, hot offset, and the like during fixing in a high temperature region.
Specific examples of the crosslinking agent include aromatic polyvinyl compounds such as divinylbenzene and divinylnaphthalene, divinyl phthalate, divinyl isophthalate, divinyl terephthalate, divinyl homophthalate, divinyl trimesate / trivinyl, and naphthalene dicarboxylic acid. Polyvinyl esters of aromatic polycarboxylic acids such as divinyl and divinyl biphenylcarboxylate, divinyl esters of nitrogen-containing aromatic compounds such as divinyl pyridinedicarboxylate, unsaturated heterocyclic compounds such as pyrrole and thiophene, and pyromutic acid Vinyl esters of unsaturated heterocyclic compounds such as vinyl, vinyl furancarboxylate, vinyl pyrrole-2-carboxylate, vinyl thiophenecarboxylate, butanediol methacrylate, hexanediol acrylate, octanedio (Meth) acrylic esters of linear polyhydric alcohols such as dimethacrylate, decanediol acrylate, dodecanediol methacrylate, etc., branching and substitution such as neopentyl glycol dimethacrylate, 2-hydroxy, 1,3-diacryloxypropane (Meth) acrylic acid esters of polyhydric alcohols, polyethylene glycol di (meth) acrylate, polypropylene polyethylene glycol di (meth) acrylates, divinyl succinate, divinyl fumarate, vinyl / divinyl maleate, divinyl diglycolate, itacon Vinyl / divinyl acetate, divinyl acetone dicarboxylate, divinyl glutarate, divinyl 3,3′-thiodipropionate, divinyl aconite / trivinyl, divinyl adipate, dipimelate Cycloalkenyl, divinyl suberate, azelate, divinyl sebacate, divinyl dodecanedioate divinyl, the polyvinyl esters of polycarboxylic acids such as oxalic acid divinyl and the like.

  In particular, in the crystalline polyester resin, for example, unsaturated polycarboxylic acids such as fumaric acid, maleic acid, itaconic acid, trans-aconitic acid, etc. are copolymerized in the polyester, and then the multiple bond portions in the resin are bonded together, Or you may use the method of bridge | crosslinking using another vinyl type compound. In addition, these crosslinking agents may be used individually by 1 type, and may be used in combination of 2 or more types.

  As a method of cross-linking with these cross-linking agents, a method of polymerizing and cross-linking with a cross-linking agent at the time of polymerization of the polymerizable monomer (monomer) may be used, or the unsaturated portion is left in the binder resin to polymerize the binder resin. Alternatively, the unsaturated portion may be cross-linked by a cross-linking reaction after toner preparation or after toner preparation.

  When the binder resin is a polyester resin, the polymerizable monomer is polymerized by condensation polymerization. As the polycondensation catalyst, known ones can be used. Specific examples include titanium tetrabutoxide, dibutyltin oxide, germanium dioxide, antimony trioxide, tin acetate, zinc acetate, tin disulfide and the like. It is done. When the binder resin is a vinyl resin, the polymerizable monomer is polymerized by radical polymerization.

  The initiator for radical polymerization is not particularly limited as long as it undergoes emulsion polymerization. Specifically, hydrogen peroxide, acetyl peroxide, cumyl peroxide, tert-butyl peroxide, propionyl peroxide, benzoyl peroxide, chlorobenzoyl peroxide, dichlorobenzoyl peroxide, bromomethylbenzoyl peroxide, lauroyl peroxide , Ammonium persulfate, sodium persulfate, potassium persulfate, diisopropyltetralin hydroperoxide, 1-phenyl-2-methylpropyl-1-hydroperoxide, pertriphenylacetic acid-tert-butyl hydroperoxide, tert-butyl formate, Peroxides such as tert-butyl peracetate, tert-butyl perbenzoate, tert-butyl perphenylacetate, tert-butyl permethoxyacetate, tert-butyl perN- (3-toluyl) carbamate, 2,2 '-Azobisp Bread, 2,2′-dichloro-2,2′-azobispropane, 1,1′-azo (methylethyl) diacetate, 2,2′-azobis (2-amidinopropane) hydrochloride, 2,2 ′ -Azobis (2-amidinopropane) nitrate, 2,2'-azobisisobutane, 2,2'-azobisisobutyramide, 2,2'-azobisisobutyronitrile, 2,2'-azobis-2- Methyl methylpropionate, 2,2′-dichloro-2,2′-azobisbutane, 2,2′-azobis-2-methylbutyronitrile, dimethyl 2,2′-azobisisobutyrate, 1,1′-azobis (1 -Sodium methylbutyronitrile-3-sulfonate), 2- (4-methylphenylazo) -2-methylmalonodinitrile, 4,4'-azobis-4-cyanovaleric acid, 3,5-dihy Roxymethylphenylazo-2-methylmalonodinitrile, 2- (4-bromophenylazo) -2-allylmalonodinitrile, 2,2′-azobis-2-methylvaleronitrile, 4,4′-azobis-4 -Dimethyl cyanovalerate, 2,2'-azobis-2,4-dimethylvaleronitrile, 1,1'-azobiscyclohexanenitrile, 2,2'-azobis-2-propylbutyronitrile, 1,1'- Azobis-1-chlorophenylethane, 1,1′-azobis-1-cyclohexanecarbonitrile, 1,1′-azobis-1-cycloheptanenitrile, 1,1′-azobis-1-phenylethane, 1,1 ′ -Azobiscumene, 4-nitrophenylazobenzyl cyanoacetate ethyl, phenylazodiphenylmethane, phenylazotriphenylmeth Tan, 4-nitrophenylazotriphenylmethane, 1,1′-azobis-1,2-diphenylethane, poly (bisphenol A-4,4′-azobis-4-cyanopentanoate), poly (tetraethylene glycol) -2,2'-azobisisobutyrate) and the like, 1,4-bis (pentaethylene) -2-tetrazene, 1,4-dimethoxycarbonyl-1,4-diphenyl-2-tetrazene and the like Can be mentioned. These polymerization initiators are also used as initiators during the crosslinking reaction.

  As the binder resin, mainly the crystalline polyester resin and the non-crystalline polyester resin have been described above. However, other styrenes such as styrene, parachlorostyrene, α-methylstyrene, etc. Acrylic monomers such as methyl acrylate, ethyl acrylate, n-propyl acrylate, butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate; methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, Methacrylic monomers such as lauryl methacrylate and 2-ethylhexyl methacrylate; ethylenically unsaturated acid monomers such as acrylic acid, methacrylic acid and sodium styrenesulfonate; and vinyl nitriles such as acrylonitrile and methacrylonitrile Vinyl vinyl ether, vinyl Vinyl ethers such as isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone; homopolymers of olefin monomers such as ethylene, propylene and butadiene, and two or more of these monomers Copolymers combined or a mixture thereof, and further, non-vinyl condensation resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, or the like and the vinyl resins A mixture, a graft polymer obtained by polymerizing a vinyl monomer in the presence of these, and the like are used.

  As will be described later, when the toner of this embodiment is prepared by the emulsion polymerization aggregation method (that is, when the resin particle dispersion is prepared by the emulsion polymerization method in the process of preparing the toner by the aggregation / unification method), The adhesion resin is prepared as a resin particle dispersion. The resin particle dispersion can be easily obtained by an emulsion polymerization method or a polymerization method similar to a heterogeneous dispersion system. The resin particle dispersion can be obtained by a method in which a polymer previously polymerized by a solution polymerization method, a cage polymerization method, or the like is added to a solvent in which the polymer is not dissolved together with a stabilizer and mechanically mixed and dispersed.

For example, when synthesizing a vinyl resin, an ionic surfactant or the like is used, and a resin particle dispersion is preferably obtained by an emulsion polymerization method or a seed polymerization method using an ionic surfactant and a nonionic surfactant in combination. Is made.
Examples of the surfactant used herein include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap; cationic surfactants such as amine salt type and quaternary ammonium salt type; Nonionic surfactants such as polyethylene glycols, alkylphenol ethylene oxide adducts, alkyl alcohol ethylene oxide adducts, polyhydric alcohols, and various graft polymers, etc., are not particularly limited. Absent.

  When preparing a resin particle dispersion by emulsion polymerization, a small amount of unsaturated acid such as acrylic acid, methacrylic acid, maleic acid, styrene sulfonic acid, etc. is added as a part of the monomer component to the particle surface. A protective colloid layer can be formed, which is particularly preferable because it becomes soap-free polymerization.

-Release agent-
The toner of the exemplary embodiment preferably contains a release agent. As the release agent, a known release agent for toner can be used. For example, low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene; Fatty acid amides such as silicones, oleic acid amide, erucic acid amide, ricinoleic acid amide, stearic acid amide; plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil; animals such as beeswax System wax; mineral wax such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, petroleum wax, and modified products thereof.

  The content of the release agent in the toner particles is preferably in the range of 0.5% by mass or more and 50% by mass or less, more preferably in the range of 1% by mass or more and 30% by mass or less, and 5% by mass or more and 15% by mass or less. A range is more preferred. If the content is less than 0.5% by mass, oilless fixing may be difficult. If the content exceeds 50% by mass, the exfoliation of the release agent on the image surface tends to be insufficient at the time of fixing. The release agent tends to stay, and the transparency of the image may be deteriorated.

The average dispersion diameter of the release agent dispersed and contained in the toner is preferably in the range of 0.3 μm to 0.8 μm, and preferably in the range of 0.4 μm to 0.8 μm. More preferred.
When the average dispersion diameter of the release agent is less than 0.3 μm, the releasability may be insufficient, and this tendency tends to become more remarkable particularly when the process speed is fast. On the other hand, when the thickness exceeds 0.8 μm, the transparency may be lowered when the OHP sheet is used, and the release agent component may be exposed to the toner surface.

The standard deviation of the dispersion diameter of the release agent is preferably 0.05 or less, and more preferably 0.04 or less. When the standard deviation of the dispersion diameter of the release agent exceeds 0.05, the release property, transparency when using the OHP sheet, and exposure of the release agent to the toner surface may be adversely affected.
The average dispersion diameter of the release agent dispersed and contained in the toner is obtained by analyzing a TEM (transmission electron microscope) photograph of a cross section of the toner particles with an image analysis apparatus (Lusex image analysis apparatus manufactured by Nireco). It is obtained by calculating the average value of the dispersion diameter (= (major axis + minor axis) / 2) of the release agent in individual toner particles, and the standard deviation is obtained based on the individual dispersion diameters obtained at this time. It was.

Further, the exposure rate of the release agent on the surface of the toner particles is preferably in the range of 5 atom% to 12 atom%, and more preferably in the range of 6 atom% to 11 atom%.
When the exposure rate is less than 5 atom%, the fixability may be deteriorated when fixing in a high temperature range, particularly when high-speed image formation with a process speed of 200 mm / s or more is performed, and when the exposure rate exceeds 12 atom%. In long-term use, the developability and transferability may be deteriorated due to uneven distribution of external additives or embedding in toner particles.

Here, the exposure rate of the release agent on the toner particle surface was determined by XPS (X-ray photoelectron spectroscopy) measurement.
The XPS measurement was performed using JPS-9000MX manufactured by JEOL Ltd. as a measuring device, using an MgKα ray as an X-ray source, setting an acceleration voltage to 10 kV, and an emission current to 30 mA.
From the C1S spectrum obtained under the above conditions, the amount of the release agent on the toner surface was quantified by peak-separating components resulting from the release agent on the toner surface. In the peak separation, the measured C1S spectrum is separated into each component using curve fitting by the least square method. As the component spectrum serving as a base for separation, a C1S spectrum obtained by independently measuring the release agent, the binder resin, and the crystalline resin used for the preparation of the toner was used.

-Colorant-
The toner of this embodiment contains a colorant.
Examples of the colorant used in the present embodiment include carbon black, chrome yellow, hansa yellow, benzidine yellow, sren yellow, quinoline yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, brilliantamine 3B. , Brilliantamine 6B, DuPont Oil Red, Pyrazolone 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 Various pigments such as acridine, xanthene, azo, benzoquinone, azine, anthraquino 1 type or 2 or more types of various dyes such as thioindico, dioxazine, thiazine, azomethine, indico, phthalocyanine, aniline black, polymethine, triphenylmethane, diphenylmethane, and thiazole You may use together.

In addition, a colorant that has been surface-modified with rosin, polymer, or the like is also used. The surface-modified colorant is stabilized in the colorant dispersion, and after the colorant is dispersed to the desired average particle size in the colorant dispersion, it is mixed with the resin particle dispersion. At this time, the colorants are not aggregated even in the aggregated particle forming step and the like, which is advantageous in that a good dispersion state is maintained. On the other hand, the colorant that has undergone an excessive surface modification treatment may be released without agglomerating with the resin particles in the aggregated particle forming step. For this reason, the surface modification treatment is performed under selected optimum conditions.
Examples of the polymer used for the surface treatment of the colorant include acrylonitrile polymer and methyl methacrylate polymer.

  The conditions for surface modification are generally a polymerization method in which a monomer is polymerized in the presence of a colorant (pigment), a colorant (pigment) is dispersed in a polymer solution, and the solubility of the polymer is lowered to reduce the colorant (pigment). ) A phase separation method that precipitates on the surface is used.

  The content of the colorant is preferably in the range of 1% by mass to 20% by mass with respect to the entire toner particles.

-Other additive components-
When the toner of this embodiment is used as a magnetic toner, magnetic powder is contained. Examples of the magnetic powder used here include metals such as ferrite, magnetite, reduced iron, cobalt, nickel, and manganese, alloys, or these metals. And the like. Furthermore, various charge control agents that are usually used, such as quaternary ammonium salts, nigrosine compounds and triphenylmethane pigments, may be added as necessary.

The toner of this embodiment may be internally added with inorganic particles as necessary. The inorganic particles having a central particle of 5 nm to 30 nm and the inorganic particle having a central particle diameter of 30 nm to 100 nm are contained in a range of 0.5% by mass to 10% by mass with respect to the toner. More preferable in terms of durability.

Examples of the inorganic particles include silica, hydrophobized silica, titanium oxide, alumina, calcium carbonate, magnesium carbonate, tricalcium phosphate, colloidal silica, cation surface-treated colloidal silica, and anion surface-treated colloidal silica. These inorganic particles are dispersed in advance in the presence of an ionic surfactant using an ultrasonic disperser or the like, and it is more preferable to use colloidal silica that does not require this dispersion treatment.

When the added amount of the inorganic particles is less than 0.5% by mass, not only the addition of the inorganic particles does not provide sufficient toughness at the time of melting the toner, but not only can the releasability in oilless fixing be improved, but also when the toner is melted. The coarse dispersion of the particles in the toner increases only the viscosity, and as a result, the spinnability is deteriorated, so that the peelability in oilless fixing may be impaired.
On the other hand, if it exceeds 10% by mass, sufficient toughness can be obtained, but the fluidity at the time of melting the toner is greatly reduced, and the gloss of the image may be impaired.

  A known external additive may be externally added to the toner of the exemplary embodiment. As the external additive, inorganic particles such as silica, alumina, titania, calcium carbonate, magnesium carbonate, and tricalcium phosphate are used. For example, as fluidity aids and cleaning aids, inorganic particles such as silica, alumina, titania and calcium carbonate, and resin particles such as vinyl resin, polyester and silicone are used. The method for adding the external additive is not particularly limited, but may be added to the toner particle surface by applying a shearing force in a dry state.

  The toner of the exemplary embodiment preferably contains two or more external additives having different Mohs hardness. By containing two or more types of external additives with different Mohs hardness, the external additive with low Mohs hardness (low hardness external additive) protects the surface of the electrophotographic photoreceptor (image carrier), and the Mohs hardness High external additive (high hardness external additive) strongly polishes the discharge product adhering to the surface of the electrophotographic photoreceptor, and is cleaned while suppressing surface scratches and uneven wear that cause image defects. The Mohs hardness is a value represented by a new Mohs hardness of 1 to 15.

The Mohs hardness of the low-hardness external additive is preferably 2 or more and 6 or less, and more preferably 3 or more and 5 or less in that the effect of protecting the surface of the electrophotographic photoreceptor is exhibited.
Further, the Mohs hardness of the high-hardness external additive is preferably 7 or more and 9 or less, and preferably 7.5 or more in that the effect of strongly polishing the discharge product or the like attached to the surface of the electrophotographic photoreceptor is exhibited. 8.5 or less is more preferable.

Preferred combinations of the low-hardness external additive and the high-hardness external additive when containing two types of external additives having different Mohs hardness include calcium carbonate and alumina, calcium sulfate and zirconia,
Examples thereof include calcium fluoride and silicon nitride.

The content ratio of the low-hardness external additive and the high-hardness external additive (low-hardness external additive: high-hardness external additive, mass ratio) is preferably 20:80 to 80:20, and 30:70 to 70:30. Is more preferable.
Further, the total content of the external additives in the toner of the exemplary embodiment is preferably 0.8 parts by mass or more and 3.5 parts by mass or less, and preferably 1 part by mass or more and 2.5 parts by mass or less with respect to 100 parts by mass of the toner. Is more preferable.

-Toner characteristics-
The toner of this embodiment preferably has a volume average particle diameter D50v in the range of 3 μm to 7 μm. If the thickness is less than 3 μm, the chargeability may be insufficient and scattering to the surroundings may occur to cause image fogging. If the thickness exceeds 7 μm, the resolution of the image may be reduced, and it may be difficult to achieve high image quality. The volume average particle diameter D50v is more preferably in the range of 5 μm to 6.5 μm.

  Further, the volume average particle size distribution index GSDv of the toner is preferably 1.28 or less. If GSDv exceeds 1.28, the sharpness and resolution of the image may decrease. On the other hand, the number average particle size distribution index GSDp is preferably 1.30 or less. When the GSDp exceeds 1.30, the ratio of the small particle size toner is increased, and thus there may be a very large influence from the viewpoint of reliability in addition to the initial performance. That is, as conventionally known, since the adhesion of small-diameter toner is large, electrostatic control is likely to be difficult, and when a two-component developer is used, it may be likely to remain on the carrier. In this case, if mechanical force is repeatedly applied, carrier contamination may be caused, and as a result, deterioration of the carrier may be promoted.

  Particularly in the transfer process, among the toners developed on the image carrier, it is difficult to transfer the small diameter component, resulting in poor transfer efficiency, resulting in increased waste toner and poor image quality. . As a result of these problems, there are cases where toners that are not electrostatically controlled and reverse-polar toners increase, which may contaminate the surroundings. In particular, the charging roll accumulates these uncontrolled toners via an image carrier or the like, which may cause charging failure.

Further, since the toner having a small diameter component tends to have insufficient inclusion of the crystalline resin, filming on the image holding member may be caused. On the other hand, a toner having a large particle size component may cause toner cracking in the developing machine, deflation from the developing machine, image quality deterioration due to charging failure, and the like.
The volume average particle size distribution index GSDv is more preferably 1.25 or less, and the number average particle size distribution index GSDp is more preferably 1.25 or less.

Here, the volume average particle diameter D50v and various particle size distribution indices of the toner are measured using Multisizer II (manufactured by Beckman-Coulter), and the electrolyte is measured using ISOTON-II (manufactured by Beckman-Coulter). .
In the measurement, a measurement sample is added in a range of 0.5 mg to 50 mg in 2 ml of a 5% by weight aqueous solution of a surfactant such as sodium alkylbenzenesulfonate as a dispersant. This is added to 100 ml to 150 ml of electrolyte.
The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment for 1 minute with an ultrasonic disperser, and the particle size distribution of particles having a particle size in the range of 2 μm to 50 μm is used with the Multisizer II type using an aperture diameter of 100 μm taking measurement. The number of particles to be sampled is 50,000.

For the particle size range (channel) divided on the basis of the particle size distribution measured in this way, the cumulative distribution is drawn from the small diameter side for each volume and number, and the cumulative particle size average particle size is 16%. Diameter D16v, cumulative number average particle diameter D16p, cumulative volume average particle diameter 50v, cumulative volume average particle diameter D50p, cumulative particle size average 84%, cumulative volume average particle diameter D84v, cumulative number average The particle size is defined as D84p.
Here, the volume average particle size distribution index (GSDv) is defined as (D84v / D16v) 1/2, and the number average particle size distribution index (GSDp) is defined as (D84p / D16p) 1/2.

  Further, the average circularity of the toner is preferably in the range of 0.940 to 0.980. If the average circularity is less than the above range, the shape becomes indeterminate, and transferability, durability, fluidity, and the like may decrease. On the other hand, if the above range is exceeded, the ratio of the spherical particles increases and the cleaning property may become difficult. The average circularity is more preferably in the range of 0.950 or more and 0.970 or less.

  In the case of a toner containing a crystalline resin, the average circularity is spherical (when the average circularity is closer to 1), and the spherical toner with a large amount of crystalline resin component may increase. Filming due to accumulation, member deterioration due to torque increase, and filming on the image carrier may occur. On the other hand, when it is on the irregular side (when the average circularity is closer to 0), it may cause toner cracking in the developing machine, and the crystalline resin component may be exposed at the cracked interface, thereby impairing charging properties, etc. There is.

The average circularity of the toner is measured by a flow type particle image analyzer FPIA-2000 (manufactured by Toa Medical Electronics Co., Ltd.). As a specific measurement method, 0.1 to 0.5 ml of a surfactant, for example, alkylbenzesulfonate is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance, and a measurement sample is further added. Add about 0.1g to 0.5g.
The suspension in which the measurement sample is dispersed is subjected to a dispersion treatment for 1 to 3 minutes with an ultrasonic wave disperser, and the average circularity of the toner is measured with the above apparatus with a dispersion concentration of 3000 to 10,000 / μl.

  The glass transition temperature Tg of the toner of the present embodiment is not particularly limited, but a range of 45 ° C. or more and 60 ° C. is preferably selected. Below the above range, problems such as toner storage stability, fixed image storage stability, and durability in the actual machine may occur. If it is higher than the above range, problems such as an increase in the fixing temperature and an increase in the temperature required for granulation may occur.

  In addition, Tg is measured based on ASTMD3418-8 using a DSC measuring machine (differential thermal analyzer DSC60A, manufactured by Shimadzu Corporation). The temperature correction of the detection part of the apparatus uses the melting points of indium and zinc, and the correction of heat quantity uses the heat of fusion of indium. As the sample, an aluminum pan is used, an empty pan is set as a control, and the measurement is performed at a heating rate of 10 ° C./min.

The charge amount of the electrostatic image developing toner of the present embodiment is preferably in the range of 10 μC / g to 40 μC / g in absolute value, and more preferably in the range of 15 μC / g to 35 μC / g. When it is less than 10 μC / g, background stains are likely to occur, and when it exceeds 40 μC / g, the image density is likely to decrease.
Further, the ratio of the charge amount in the summer (28 ° C., 85% RH) of the electrostatic image developing toner to the charge amount in the winter (10 ° C., 30% RH) is preferably 0.5 or more and 1.5 or less. 0.7 or more and 1.3 or less are more preferable. If this ratio is out of the above range, the environmental dependency of the toner becomes strong, the charging property is not stable, and this is not preferable in practice.

-Toner production method-
As a method for producing the toner, for example, after preparing a resin particle dispersion by agglomeration and coalescence (emulsion polymerization, forced emulsification, phase inversion emulsification, etc.) and a colorant dispersion in which a colorant is dispersed in a solvent, , These are mixed to form an agglomerate corresponding to the particle size of the toner, and then heated to fuse and coalesce into a toner, and a suspension polymerization method (release agent, colorant, etc. is required) The component used according to the method is suspended together with a polymerizable monomer that forms a binder resin such as a crystalline resin, and the polymerizable monomer is polymerized to form a toner). A compound having an ionic dissociation group, a binder resin such as a crystalline resin, and a toner constituent material such as a release agent are dissolved in an organic solvent, dispersed in an aqueous solvent in a suspended state, and then the organic solvent is removed. And a wet manufacturing method such as a toner manufacturing method).

Hereinafter, an aggregation / unification method will be described as an example of a toner manufacturing method according to the present exemplary embodiment.
The toner manufacturing method in the present embodiment includes, for example, a resin particle dispersion adjusting step for adjusting a resin particle dispersion in which resin particles are dispersed, and a colorant particle dispersion for adjusting a colorant particle dispersion in which colorant particles are dispersed. A liquid adjustment step, a mixed solution adjustment step of mixing a resin particle dispersion and a colorant particle dispersion to adjust a mixed solution containing the resin particles and the colorant particles, and an aggregated particle in which the resin particles and the colorant particles are aggregated An agglomerated particle adjusting step for adjusting, and an aggregating / unifying step of fusing and coalescing the aggregated particle dispersion in which the agglomerated particles are dispersed to a temperature higher than the glass transition temperature of the resin particles.
Moreover, you may include other processes, such as the mold release agent particle dispersion liquid adjustment process which adjusts the mold release agent particle dispersion liquid which disperse the mold release agent particle as needed.

In this embodiment, at least one of the resin particle dispersion adjusting step, the colorant particle dispersion adjusting step, the release agent particle dispersion adjusting step, and the mixed solution adjusting step is a biodegradable dispersant. The process of adding.
That is, as long as the biodegradable dispersant is included in the mixed solution adjusted in the mixed solution adjusting step, the biodegradable dispersant may be added in any of the above steps.

Specifically, for example, when preparing a colorant particle dispersion containing a biodegradable dispersant, the biodegradable dispersant may be added to the solvent before the colorant is dispersed in the solvent, or the colorant A biodegradable dispersant may be added to the dispersion after the dispersion.
For example, when preparing a mixed solution containing a biodegradable dispersant, the biodegradable dispersant is added to any one or more of the resin particle dispersion, the colorant particle dispersion, and the release agent particle dispersion to be mixed. Or a biodegradable dispersant may be added to the solution after mixing the dispersion.

By including the step of adding a biodegradable dispersant in the above step, a toner in which the toner constituent components are uniformly blended and the impurities are low can be obtained. The reason is not clear, but is presumed as follows.
The biodegradable dispersant is decomposed into an acid component and an alcohol component by heating in the aggregated particle adjustment step. And when particle | grains aggregate in an aggregated particle adjustment process, the acid component of the decomposition product contributes to aggregation behavior stabilization, and an alcohol component contributes to suppression of rapid aggregation. Therefore, uneven distribution of raw materials (binder resin, colorant, etc.) in the aggregated particles is difficult to occur. That is, even when different materials that are difficult to mix are mixed, the constituent materials are not unevenly distributed, and it is estimated that uniformly mixed aggregated particles are generated.

In addition, the biodegradable dispersant remaining without being decomposed in the aggregated particle adjusting step is also heated or added with acid or alkali in the step after the aggregated particles are formed (for example, the fusion / union step). Therefore, it is easy to be decomposed and removed, so that it hardly remains in the toner. Note that the temperature and pH at which the biodegradable dispersant is decomposed differ depending on the compound contained in the biodegradable dispersant. For example, when polyoxyethylene lauryl ether sodium acetate as a biodegradable dispersant is decomposed, it is heated to 80 ° C. or higher, an acid is added to pH = 3.0 or lower, or pH = 9.0 or higher It is preferable to add an alkali.
In addition, since the biodegradable dispersant is easily decomposed, the biodegradable dispersant is decomposed by itself even if heating or addition of acid or alkali is performed in the aggregated particle adjustment process or fusion / coalescence process. Is suppressed.

  Further, the decomposition product of the biodegradable dispersant remaining in the toner coordinates an ionic impurity contained in the toner, thereby suppressing an adverse effect on the toner due to the ionic impurity. Therefore, even when a material having a high specific electrical conductivity that has been difficult to use in the wet method is used, a toner in which the uneven distribution of the constituent components is suppressed can be obtained.

In particular, when an ether carboxylic acid compound is used as the biodegradable dispersant, the ether carboxylic acid compound dissolves in the solvent while coordinating ionic impurities (particularly cationic impurities) in the mixed solution. That is, it is presumed that the ether carboxylic acid compound suppresses the ionic impurities from being taken into the aggregated particles and selectively causes the ionic impurities to be unevenly distributed on the toner surface.
On the other hand, when a sulfate ester compound is used in addition to an ether carboxylic acid compound as a biodegradable dispersant, it is prevented from adsorbing on the surface of resin particles, colorant particles, release agent particles, etc. and aggregating with the same material itself. Alternatively, the effect of reducing the initial aggregation unit can be obtained. That is, in the aggregated particle adjustment step, the sulfate ester compound functions as a dispersion stabilizer and further suppresses uneven distribution of constituent materials.

  The biodegradable dispersant is preferably added to the toner constituent materials (binder resin, colorant, release agent, etc.) in order to obtain more effects. For example, after premixing the colorant particle dispersion or colorant particle cake (solid material from which the solvent has been removed from the colorant particle dispersion) and the biodegradable dispersant, it is also preferable to heat to promote reactivity. Done. In this case, the heating temperature is preferably 30 ° C. or higher and 60 ° C. or lower, and more preferably 35 ° C. or higher and 55 ° C. or lower in that it can be performed while promoting the dispersibility while suppressing the cohesive force of the colorant.

In the mixed solution adjusting step, in addition to the resin particle dispersion and the colorant particle dispersion, other dispersions such as a release agent particle dispersion and an inorganic particle dispersion may be added. In particular, when an inorganic particle dispersion having a hydrophobic surface is used as the inorganic particle dispersion, the dispersibility of the release agent and the crystalline resin inside the toner is controlled by the degree of hydrophobicity.
In addition to the resin particles and the colorant particles, the agglomerated particles may be agglomerated particles that are aggregated by including other components such as a release agent particle. Further, it may be an aggregated particle having a core / shell structure to which resin particles are attached. Hereinafter, the step of attaching the resin particles to the surface of the core particle may be referred to as “attachment step”.

  The amount of the biodegradable dispersant added is preferably 1 part by mass or more and 20 parts by mass or less, more preferably 2 parts by mass or more and 18 parts by mass or less, with respect to 100 parts by mass of the resin particles (binder resin). More preferably, it is at least 15 parts by mass. Biodegradable dispersants are decomposed during the toner manufacturing process (for example, agglomeration process, coalescence and coalescence process, etc.) and are less likely to remain in the manufactured toner. At most, toner characteristics and image quality are good.

When an ether carboxylic acid compound is used as the biodegradable dispersant, the addition amount of the ether carboxylic acid compound is preferably 0.5 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass of the resin particles. Is more preferably 1.5 parts by mass or more and 5 parts by mass or less.
Moreover, when using together an ether carboxylic acid compound and a sulfate ester compound as a biodegradable dispersant, the total addition amount of the sulfate ester compound is preferably 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the resin particles. 2 mass parts or more and 9 mass parts or less are more preferable, and 3 mass parts or more and 8 mass parts or less are still more preferable.

When the addition amount of the ether carboxylic acid compound and the addition amount of the sulfate ester compound are lower than the above ranges, the dispersing action and the impurity removing action with respect to the colorant and the release agent may be lowered. In this case, the electrical characteristics may deteriorate, fogging may occur, or filming on the photoconductor may occur due to a decrease in strength due to composition variation in the toner.
On the other hand, when the addition amount of the ether carboxylic acid compound and the addition amount of the sulfate ester compound exceed the above ranges, the dispersion action and the impurity removal action can be obtained, but the residual amount of the dispersant itself in the toner may increase. In some cases, the process becomes complicated to remove the agent, or the dispersant remains in the toner without being completely removed, and as a result of long-term use, the image quality such as fogging may be affected.

Further, when an ether carboxylic acid compound and a sulfate ester compound are used in combination as a biodegradable dispersant, the addition amount of the ether carboxylic acid compound is preferably 2 to 7 times the addition amount of the sulfate ester compound, preferably 2.5 times. It is more preferably 6 times or less and further preferably 3 times or more and 5.5 times or less.
When the biodegradable dispersant is added in a plurality of steps, it is preferable that the total addition amount in each step is in the above range.

Hereinafter, each step will be specifically described. In addition, the overlapping part may be abbreviate | omitted among the description regarding the above-mentioned biodegradable dispersing agent.
(Resin particle dispersion adjustment process)
As described above, the resin particle dispersion is obtained in the state of resin particle dispersion when the emulsion polymerization method or the like is used in the synthesis of the binder resin.

On the other hand, when a binder resin is obtained by polymerizing in advance by a solution polymerization method, a cage polymerization method, or the like, as described above, the obtained binder resin and the stabilizer are added in a solvent, and mechanically added. By mixing and dispersing, a resin particle dispersion can be obtained. That is, for example, it is performed by applying a shearing force to a solution obtained by mixing an aqueous medium and a binder resin with a disperser. At that time, particles may be formed by heating to lower the viscosity of the resin component. A dispersant may be used for stabilizing the dispersed resin particles.
Furthermore, if the binder resin is oily and dissolves in a solvent with a relatively low solubility in water, the resin is dissolved in those solvents and dispersed in water together with a dispersant and a polymer electrolyte, and then heated or decompressed. Then, the resin particle dispersion may be prepared by evaporating the solvent.

Examples of the disperser include a homogenizer, a homomixer, a pressure kneader, an extruder, and a media disperser.
Examples of the aqueous medium include water such as distilled water and ion-exchanged water; alcohols; and the like.

  Examples of the dispersant include water-soluble polymers such as polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, and sodium polymethacrylate; sodium dodecylbenzenesulfonate, sodium octadecylsulfate, and oleic acid. Anionic surfactants such as sodium, sodium laurate, potassium stearate, cationic surfactants such as laurylamine acetate, stearylamine acetate, lauryltrimethylammonium chloride, zwitterionic surfactants such as lauryldimethylamine oxide, Polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl amine, etc. Surfactants such as on-surfactants; and the like are; tricalcium phosphate, aluminum hydroxide, calcium sulfate, calcium carbonate, inorganic salts such as barium carbonate.

  Among the above, it is preferable to use a biodegradable dispersant as the dispersant. However, if the mixed solution contains a biodegradable dispersant, only a dispersant other than the biodegradable dispersant may be used. In addition, a biodegradable dispersant and a dispersant other than the biodegradable dispersant may be used in combination.

  The content of the resin particles contained in the resin particle dispersion is preferably in the range of 10 to 50% by mass, more preferably in the range of 20 to 40% by mass. When the content is less than 10% by mass, the particle size distribution is widened and the toner characteristics may be deteriorated. On the other hand, if it exceeds 50% by mass, uniform stirring becomes difficult, and it may be difficult to obtain a toner having a narrow particle size distribution and uniform characteristics.

The volume average particle size of the resin particles in the resin particle dispersion is desirably 1 μm or less, and more desirably 0.01 μm or more and 1 μm or less. If the average particle size of the resin particles exceeds 1 μm, the particle size distribution of the finally obtained toner may be broadened, or free particles may be generated, resulting in a decrease in performance and reliability.
On the other hand, when the average particle diameter of the resin particles is within the above range, the above disadvantages are eliminated, uneven distribution among the toners is reduced, dispersion in the toners is improved, and variations in performance and reliability are reduced. It is advantageous. The volume average particle size of the resin particles is measured using, for example, a laser diffraction particle size distribution measuring device (manufactured by Shimadzu Corporation, SALD2000A).

(Colorant particle dispersion adjustment process)
As a method for dispersing the colorant in the solvent, for example, a rotary shearing homogenizer, a ball mill having media, a sand mill, a dyno mill, or the like is employed.
As a solvent, the thing similar to the aqueous solvent used in the said resin particle dispersion liquid is mentioned.

A dispersant may be used for stabilizing the dispersed colorant particles. Examples of the dispersant include the same dispersants as those used in the resin particle dispersion, and among them, a biodegradable dispersant is preferably used.
In particular, when a pigment is used as a colorant, it is preferable to add a biodegradable dispersant in the colorant particle adjustment step because the pigment often contains ionic impurities. It is more desirable to premix and heat the biodegradable dispersant to the colorant particle cake.

The volume average particle diameter of the colorant particles is preferably 0.8 μm or less, and more preferably 0.05 μm or more and 0.5 μm or less.
If the volume average particle size of the colorant particles exceeds 0.8 μm, the particle size distribution of the finally obtained toner may be widened, or free particles may be generated, leading to a decrease in performance and reliability. . Further, when the average particle diameter of the colorant particles is smaller than 0.05 μm, not only the colorability in the toner is lowered but also the shape controllability, which is one of the characteristics of the aggregation / unification method, is impaired. In some cases, a toner having a shape close to a sphere cannot be obtained.

Further, the proportion of coarse particles having a volume average particle size of 0.8 μm or more in the colorant particle dispersion is preferably less than 10% by number, and more preferably close to 0% by number. The presence of the coarse particles may impair the stability of the formed aggregated particles in the aggregated particle forming step. In addition, coarse colored particles may be liberated or the particle size distribution may be widened.
Further, the proportion of fine particles having a volume average particle size of 0.05 μm or less in the colorant particle dispersion is preferably 5% by number or less. The presence of the fine particles impairs the shape controllability of the toner particles in the coalescence and coalescence process, and the average circularity of 0.940 or less may not be obtained.

On the other hand, when the average particle diameter, coarse particles, and fine particles of the colorant are within the above ranges, the above disadvantages are eliminated and the uneven distribution of the components among the toners is reduced, and the dispersion of the components in the toners is improved. This is advantageous in that variations in performance and reliability are reduced.
The volume average particle diameter of the colorant particles is also measured using a laser diffraction particle size distribution measuring device (SALD2000A, manufactured by Shimadzu Corporation).

(Release agent particle dispersion adjustment process)
The release agent particle dispersion is prepared by dispersing it in the above aqueous solvent together with a polymer electrolyte such as an ionic surfactant, polymer acid, polymer base, etc., heating it above its melting point, and applying a strong shearing force. The particles are formed using a homogenizer or a pressure discharge type disperser.

(Mixed solution adjustment process)
The mixed solution is prepared by mixing the resin particle dispersion, the colorant particle dispersion, and other dispersions such as a release agent particle dispersion as necessary. At this time, the release agent particle dispersion may be added at once in the mixed solution adjustment step, or may be divided and added in multiple stages.

(Aggregated particle adjustment process)
In the aggregated particle adjustment step, the mixed solution is heated to form aggregated particles in which the particles in the mixed solution are aggregated. Note that the heating is desirably performed in a temperature range lower than the melting point of the crystalline resin (a temperature lower by 20 ° C. to 10 ° C. than the melting point of the crystalline resin).

Agglomerated particles are formed by stirring with a rotary shearing homogenizer. Specifically, for example, an aggregating agent is added at 20 ° C. to 30 ° C. to make the pH of the raw material dispersion acidic (eg, pH = 2.8). Is made by
The flocculant used in the agglomerated particle forming step can take a valence of 2 or more in addition to a surfactant having a reverse polarity to the surfactant used as a dispersant added to the raw material dispersion, that is, an inorganic metal salt. A metal complex containing a metal element is preferably used. In particular, the use of a metal complex is particularly preferable because the amount of the surfactant used can be reduced and the charging characteristics are improved.

  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. Examples thereof include inorganic metal salt polymers. Of these, aluminum salts and polymers thereof are particularly preferred. In order to obtain a sharper particle size distribution, the valence of the inorganic metal salt is bivalent than monovalent, trivalent than bivalent, trivalent than trivalent, and tetravalent than trivalent. The inorganic metal salt polymer is more suitable.

  Examples of the metal complex containing a metal element capable of taking a valence of 2 or more include a metal salt of aminocarboxylic acid. Specific examples include calcium salts, magnesium salts, iron salts, aluminum salts, and the like based on known chelates such as ethylenediaminetetraacetic acid, propanediaminetetraacetic acid, nitriletriacetic acid, triethylenetetraminehexaacetic acid, diethylenetriaminepentaacetic acid, and the like. It is done.

The inorganic metal salt is preferably dispersed in a solvent to form an inorganic particle dispersion, which is added to the mixed solution in advance in the mixed solution preparation step and simultaneously aggregated. As a result, the inorganic metal salt effectively acts on the molecular chain terminal of the binder resin and contributes to the formation of a crosslinked structure.
The inorganic particle dispersion is prepared by an arbitrary method, for example, using a ball mill, a sand mill, an ultrasonic disperser rotary shearing type homogenizer, or the like.

  The inorganic particle dispersion may be added stepwise in the aggregated particle forming step, or may be added continuously. These methods are effective in dispersing the metal ion component in the inorganic particle dispersion from the toner surface to the inside. When adding stepwise, it is particularly preferable to add the dispersion at a slow rate of about 0.1 g / m or less when adding continuously in three steps or more.

  The amount of the inorganic particle dispersion added varies depending on the type of metal required and the degree of formation of the crosslinked structure, but is in the range of 0.5 to 10 parts by mass with respect to 100 parts by mass of the binder resin. It is preferable to set it in a range of 1 part by mass or more and 5 parts by mass or less.

In the agglomerated particle forming step, toner particles can be prepared by adjusting the type and amount of inorganic metal salt or metal complex containing a metal element capable of taking a valence of 2 or more without affecting the formation of agglomerated particles. You may control content of the metal element which can take the valence more than bivalence contained in it.
In addition, from the viewpoint that it is easier to achieve both a low-temperature fixability and a gloss unevenness suppressing effect at a high level, it is preferable to use aluminum sulfate, polyaluminum chloride, or calcium chloride among the flocculants listed above. It is.

The aggregated particle forming step may include an attaching step as necessary. In the attaching step, the coating layer is formed by attaching resin particles to the surface of the aggregated particles (core particles) formed through the above-described aggregated particle forming step. Thus, a toner having a so-called core layer and a core / shell structure covering the core layer is obtained.

  The coating layer is usually formed by additionally adding a resin particle dispersion containing non-crystalline resin particles to the dispersion in which aggregated particles (core particles) are formed in the aggregated particle forming step. In addition, when the amorphous resin is used in addition to the crystalline resin in the step of forming the core particles, the non-crystalline resin used in the adhesion step may be the same as that used in the aggregated particle forming step. It may be.

  In general, the adhesion process is used when a toner having a so-called core / shell structure in which a crystalline resin as a main component is contained as a binder resin together with a release agent, and the main purpose thereof is the core layer. The purpose is to suppress the exposure of the release agent and the crystalline resin contained on the toner surface, and to supplement the strength of the toner particles, which is insufficient with the core layer alone.

(Fusion / unification process)
In the fusion / unification step performed after the aggregated particle forming step, the pH of the suspension containing the aggregated particles formed through these steps is in a desired range (pH is 2.5 or more and pH 5.5 or less). Thus, after the progress of aggregation is stopped, the aggregated particles are fused by heating.

The pH is adjusted by adding an acid and / or alkali. Although an acid is not specifically limited, The aqueous solution which contains inorganic acids, such as hydrochloric acid, nitric acid, and a sulfuric acid, in 0.1 to 50 mass% is preferable. The alkali is not particularly limited, but an aqueous solution containing an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide in the range of 0.1% by mass to 50% by mass is preferable.
In the pH adjustment, if a local pH change occurs, local aggregated particles themselves may be destroyed or local excessive aggregation may be caused, and the shape distribution may be deteriorated. In particular, the larger the scale, the greater the amount of acid and / or alkali. In general, there is only one place where the acid and alkali are added, so that if the treatment is performed in the same time, the concentration of acid and alkali at the place where the scale is increased increases.

  After performing the composition control described above, the aggregated particles are heated and fused. In the fusion, the aggregated particles are fused by heating at a temperature of 10 to 30 ° C. or higher from the melting point of the crystalline resin (or the glass transition temperature of the amorphous resin when an amorphous resin is used).

The cross-linking reaction may be performed with other components during the heating at the time of fusion or after the fusion is completed. Further, a crosslinking reaction may be performed simultaneously with the fusion. When the crosslinking reaction is performed, the above-described crosslinking agent and polymerization initiator are used in the production of the toner.
The polymerization initiator may be mixed with the dispersion in advance at the stage of preparing the raw material dispersion, or may be incorporated into the aggregated particles in the aggregated particle forming step. Furthermore, it may be introduced after the fusion / unification step or after the fusion / unification step. In the case of introduction after the aggregated particle forming step, the adhering step, the fusing / merging step, or the fusing / merging step, a solution in which the polymerization initiator is dissolved or emulsified is added to the dispersion. These polymerization initiators may be added with known crosslinking agents, chain transfer agents, polymerization inhibitors and the like for the purpose of controlling the degree of polymerization.

(Washing, drying process, etc.)
After completing the coalescence and coalescence process of the aggregated particles, the desired toner particles are obtained through a washing process, a solid-liquid separation process, and a drying process as necessary. Replacement cleaning is desirable. Moreover, although there is no restriction | limiting in particular in a solid-liquid separation process, From the point of productivity, suction filtration, pressure filtration, etc. are suitable. Further, the drying process is not particularly limited, but freeze drying, flash jet drying, fluidized drying, vibration fluidized drying and the like are preferably used from the viewpoint of productivity. Further, the various external additives described above are added to the toner particles after drying as necessary.

<Developer for developing electrostatic image>
The developer for developing an electrostatic charge image of the present embodiment (hereinafter sometimes referred to as “developer”) includes the toner of the present embodiment, and other components may be blended depending on the purpose. .
Specifically, when the toner of this embodiment is used alone, it becomes a one-component electrostatic image developing developer, and when used in combination with a carrier, it becomes a two-component electrostatic image developing developer. The toner concentration in the developer is preferably in the range of 1% by mass to 10% by mass.

  Here, the carrier is not particularly limited, and examples thereof include known carriers. For example, the core material described in JP-A-62-39879, JP-A-56-11461 or the like is coated with a resin layer. A known carrier such as a prepared carrier (resin-coated carrier) is used.

Examples of the core material of the resin-coated carrier include moldings such as iron powder, ferrite, and magnetite, and the average diameter is about 30 μm or more and 200 μm or less.
Examples of the coating resin for forming the coating layer include styrenes such as styrene, parachlorostyrene, and α-methylstyrene, methyl acrylate, ethyl acrylate, n-propyl acrylate, lauryl acrylate, and 2-ethylhexyl acrylate. , Α-methylene fatty acid monocarboxylic acids such as methyl methacrylate, n-propyl methacrylate, lauryl methacrylate and 2-ethylhexyl methacrylate, nitrogen-containing acrylics such as dimethylaminoethyl methacrylate, vinyl nitriles such as acrylonitrile and methacrylonitrile Vinyl pyridines such as 2-vinyl pyridine and 4-vinyl pyridine, vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether, vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone and other vinyl ethers. Nyl ketones, olefins such as ethylene and propylene, homopolymers such as vinyl-based fluorine-containing monomers such as vinylidene fluoride, tetrafluoroethylene and hexafluoroethylene, or copolymers comprising two or more monomers, methyl silicone, Examples thereof include silicones such as methylphenyl silicone, polyesters containing bisphenol and glycol, epoxy resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, polycarbonate resins and the like. These resins may be used alone or in combination of two or more.

  The amount of the coating resin is preferably in the range of 0.1 to 10 parts by mass and more preferably in the range of 0.5 to 3.0 parts by mass with respect to 100 parts by mass of the core material. For the production of the carrier, for example, a heating kneader, a heating Henschel mixer, a UM mixer, or the like can be used. Depending on the amount of the coating resin, a heating fluidized rolling bed, a heating kiln, or the like may be used. . The mixing ratio of the toner and the carrier in the electrophotographic developer is not particularly limited, and is selected according to the purpose.

<Image forming method>
Next, an image forming method using the developer of this embodiment will be described.
As a method for forming an image using the toner of the present embodiment, a known electrophotographic method is used. Specifically, the surface of a latent image holding member (hereinafter sometimes referred to as “image holding member”). An electrostatic latent image forming step for forming an electrostatic latent image on the toner, a developing step for developing the electrostatic latent image with a developer containing toner to form a toner image, and a transfer for transferring the toner image to a recording medium. Preferably, the method includes a step and a fixing step of fixing the toner image to the recording medium.
In addition to these steps, a known process used in an electrophotographic image forming method may be combined. For example, a toner that removes residual toner remaining on the surface of the image carrier after the transfer process is completed. It may include a removing step and a residual toner collecting and supplying step of collecting the residual toner removed in the toner removing step and supplying the collected residual toner to the developing unit. The residual toner supplied to the developing means is reused (recycled) as developer toner.

Here, the electrostatic latent image forming step is a step of forming an electrostatic latent image by charging the surface of the image carrier with a charging unit and then exposing the image carrier with a laser optical system or an LED array. is there. Examples of the charging means include a non-contact type charger such as corotron and scorotron, and a conductive member brought into contact with the surface of the image carrier (here, “conductive” means, for example, a volume resistivity of 10 ^7. A contact-type charger that charges the surface of the image carrier by applying a voltage to (means less than Ω · cm), and any type of charger may be used. However, a contact charging type charger is preferable from the viewpoint that the amount of ozone generated is small, the environment is friendly, and the printing durability is excellent. In the contact charging type charger, the shape of the conductive member may be any of a brush shape, a blade shape, a pin electrode shape, a roller shape, and the like, and is not limited. Note that the latent image forming step is not limited to the above-described embodiment.

  In the developing step, a developer carrier having a developer layer containing at least toner on the surface thereof is brought into contact with or close to the surface of the image carrier, and toner particles are formed on the electrostatic latent image on the surface of the image carrier. Is a step of forming a toner image on the surface of the image carrier. The development method is performed using a known method, and examples of the development method when the developer is a two-component developer include a cascade method and a magnetic brush method. The developing method is not limited to the above-described mode.

  The transfer step is a step of transferring a toner image formed on the surface of the image carrier to a recording medium. The transfer process may be a system in which a toner image is directly transferred onto a recording medium such as paper, or a system in which the toner image is transferred onto a recording medium such as paper after being transferred onto a drum-like or belt-like intermediate transfer member. The transfer method is not limited to the above-described mode.

  For example, a corotron is used as a transfer device (transfer means) that transfers the toner image from the image carrier to paper or the like. The corotron is effective as a means for charging the paper, but in order to give a predetermined charge to the paper as a recording medium, a high voltage of several kV must be applied and a high voltage power source is required. In addition, ozone is generated by corona discharge, which causes deterioration of rubber parts and the image carrier. Therefore, contact transfer that transfers a toner image onto a sheet by pressing a conductive transfer roll having an elastic material against the image carrier. The method is preferred. The transfer device is not limited to the above-described embodiment.

  The toner removal step (cleaning step) is a step in which a blade, brush, roll, or the like is brought into direct contact with the surface of the image carrier to remove toner, paper dust, dust, etc. adhering to the surface of the image carrier.

The most commonly adopted method is a blade cleaning method in which a rubber blade such as polyurethane is pressed against an image carrier. On the other hand, a magnetic brush method in which a magnet is fixedly arranged inside, a cylindrical non-magnetic sleeve that rotates on the outer periphery thereof is provided, and a magnetic carrier is held on the sleeve surface to collect toner, Conductive (here, “semi-conductive” means, for example, a volume resistivity of 10 ⁷ Ωcm or more and less than 10 ¹³ Ωcm) resin fibers or animal hairs arranged so as to be rotated in a roll shape, and toner Alternatively, the toner may be removed by applying a bias having the opposite polarity to the roll. In the former magnetic brush system, a pretreatment corotron for cleaning may be installed. The cleaning method is not limited to the above-described mode.

  The fixing step is a step of fixing the toner image transferred on the surface of the recording medium by a fixing unit. As the fixing means, a heat fixing apparatus using a heat roll is preferably used. The heat fixing device includes a fixing roller having a heater lamp for heating inside a cylindrical metal core, a so-called release layer formed on the outer peripheral surface by a heat resistant resin film layer or a heat resistant rubber film layer, and the fixing roller. The pressure roller or the pressure belt is arranged in pressure contact with the roller and has a layer containing a heat-resistant elastic material formed on the outer peripheral surface of the cylindrical metal core or the surface of the belt-like base material. In the toner image fixing process, a recording medium on which a toner image is formed is passed through a contact portion formed by a fixing roller and a pressure roller or a pressure belt, and heat of binder resin, additives, etc. in the toner is passed. Fix by melting. However, the fixing method is not limited to the above-described mode.

In the case of producing a full-color image, each of the plurality of image holding bodies has a developer holding body for each color, and a latent image forming step using each of the plurality of image holding bodies and the developer holding bodies, and a toner image Through a series of steps including a forming step, a transfer step, and a cleaning step, each color toner image for each step is sequentially stacked on the same recording medium surface, and the stacked full-color toner images are thermally fixed in the fixing step. An image forming method is preferably used.
By using the developer of this embodiment in the image forming method, stable development, transfer, and fixing performance can be obtained even in a tandem system suitable for, for example, small size and high color speed.

<Image forming apparatus, toner cartridge>
The image forming apparatus of the present embodiment includes an image carrier, a charging unit that charges the surface of the image carrier, an electrostatic latent image forming unit that forms an electrostatic latent image on the charged surface of the image carrier, Developing means for developing the electrostatic latent image with the developer to form a toner image, transfer means for transferring the toner image to the surface of the recording medium, and fixing for fixing the toner image transferred to the surface of the recording medium And a toner removing means for removing toner remaining on the surface of the image carrier after transfer, wherein the developer is the developer of the present embodiment described above. Since the image forming apparatus of this embodiment uses the developer of this embodiment, a high-quality image is formed over a long period of time.

  The image forming apparatus according to the present exemplary embodiment may further include a residual toner collecting / supplying unit that collects the residual toner removed by the toner removing unit and supplies the collected residual toner to the developing unit. In the present embodiment, since the developer of the present embodiment is used as the developer, the durability of the toner is high, and a high-quality image can be formed over a long period of time even when the toner is reused.

  Hereinafter, the image forming apparatus of this embodiment will be described in detail with reference to the drawings. In addition, the same code | symbol is provided to the member which has the substantially same function through all the drawings, and the overlapping description may be abbreviate | omitted.

-First embodiment-
FIG. 1 is a configuration diagram illustrating an image forming apparatus according to the first embodiment. The image forming apparatus shown in FIG. 1 is a quadruple tandem full-color image forming apparatus. Each color of yellow (Y), magenta (M), cyan (C), and black (K) based on the color-separated image data. Are provided with first to fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) of an electrophotographic system for outputting the above image. 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 urged 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 the support roller 24. 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 each unit 10Y, 10M, 10C, and 10K contains developer containing toner of four colors of yellow, magenta, cyan, and black. Yes. Further, toners of four colors, yellow, magenta, cyan, and black, stored in the toner cartridges 8Y, 8M, 8C, and 8K are supplied to the developing devices 4Y, 4M, 4C, and 4K, respectively.

  Since the first to fourth units 10Y, 10M, 10C, and 10K have the same configuration, the first unit that forms a yellow image disposed on the upstream side in the intermediate transfer belt traveling direction here. 10Y will be described as a representative. Note that the second to fourth units are given the same 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 (latent image holder) that acts as an image holder. Details of the image carrier will be described later. Around the photoreceptor 1Y, an electrostatic latent image is formed by exposing the surface of the photoreceptor 1Y to a predetermined potential with a charging roller 2Y and exposing the charged surface with a laser beam 3Y based on the color-separated image signal. An exposure device 3 (electrostatic latent image forming means) for developing, a developing device 4Y (developing means) for supplying the charged toner to the electrostatic latent image to develop the electrostatic latent image, and the developed toner image on the intermediate transfer belt 20 A primary transfer roller 5Y for transferring (temporarily transferring) the toner and a cleaning device (toner removing means) 6Y for removing the toner remaining on the surface of the photoreceptor 1Y after the primary transfer are arranged in this order.
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. At this development position, the electrostatic latent image on the photoreceptor 1Y is visualized (developed) by the developing device 4Y.

  Developer including yellow toner is accommodated in the developing device 4Y. 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 a multiple manner through the first to fourth units 10Y, 10M, 10C, and 10K includes the intermediate transfer belt 20 and the support roller 24 that contacts the inner surface of the intermediate transfer belt 20 and the intermediate transfer belt 20. To a secondary transfer portion composed of a secondary transfer roller 26 disposed on the image holding surface side. On the other hand, the recording medium P (transfer object) 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 medium P is applied to the toner image, so The toner image is transferred onto the recording medium P. The secondary transfer bias at this time is determined according to the resistance detected by a resistance detection means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

Thereafter, the recording medium P is sent to a fixing device (fixing means) 28, the toner image is heated, and the color-superposed toner image is melted and fixed on the recording medium P. The recording medium P on which the color image has been fixed is unloaded to 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 to the recording medium P via the intermediate transfer belt 20, but is not limited to this configuration, and the toner image is directly transferred from the photoconductor. It may be a structure transferred to a recording medium.

  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 are attached to and detached from each other. The developing devices 4Y, 4M, 4C, and 4K each have their respective developing devices (colors). And a toner supply pipe (not shown). Further, when the amount of toner stored in the toner cartridge is low, this toner cartridge may be replaced.

-Second Embodiment-
FIG. 2 is a cross-sectional view schematically showing a basic configuration of an image forming apparatus according to another preferred embodiment (second embodiment).
The image forming apparatus shown in FIG. 2 employs a system in which the developer according to the present exemplary embodiment is appropriately supplied to the developer storage container in the developing unit by the developer supplying unit.

  In the image forming apparatus shown in FIG. 2, the residual toner removed from the surface of the latent image holding member by the cleaning blade of the cleaning means (toner removing means) is collected and supplied to the developing means, whereby the residual toner is reused. The toner reclaim method is adopted.

  As shown in FIG. 2, the image forming apparatus 100 according to the present embodiment includes an electrostatic latent image holding body 110 (latent image holding body) that rotates clockwise as indicated by an arrow a, and an electrostatic latent image. Above the holding body 110, the charging means 120 is provided relative to the electrostatic latent image holding body 110 and charges the surface of the electrostatic latent image holding body 110 negatively, and the electrostatic latent image charged by the charging means 120 An electrostatic latent image forming unit 130 for writing an image to be formed with a developer (toner) on the surface of the holding body 110 to form an electrostatic latent image, and a downstream side of the electrostatic latent image forming unit 130 are provided. A developing unit 140 that forms a toner image on the surface of the electrostatic latent image holding member 110 by attaching toner to the electrostatic latent image formed by the electrostatic latent image forming unit 130; Travel in the direction indicated by arrow b while touching, and hold electrostatic latent image The endless belt-shaped intermediate transfer belt 150 for transferring the toner image formed on the surface of the 110 and the surface of the electrostatic latent image holding body 110 after the toner image is transferred to the intermediate transfer belt 150 are neutralized to the surface. A neutralization unit 160 that makes it easy to remove the remaining transfer residual toner, and a cleaning unit 170 (toner removal unit) that cleans the surface of the electrostatic latent image holding member 110 to remove the transfer residual toner.

  The charging unit 120, the electrostatic latent image forming unit 130, the developing unit 140, the intermediate transfer belt 150, the neutralizing unit 160, and the cleaning unit 170 are arranged in a clockwise direction on the circumference surrounding the electrostatic latent image holding body 110. It is installed.

  The intermediate transfer belt 150 is tensioned and held from the inside by the stretching rollers 150A and 150B, the backup roller 150C, and the driving roller 150D, and is driven in the direction of the arrow b as the driving roller 150D rotates. At a position opposite to the electrostatic latent image holder 110 inside the intermediate transfer belt 150, the intermediate transfer belt 150 is positively charged, and the toner on the electrostatic latent image holder 110 is placed on the outer surface of the intermediate transfer belt 150. A primary transfer roller 151 that adsorbs the toner is provided. On the outer side below the intermediate transfer belt 150, the recording medium P is positively charged and pressed against the intermediate transfer belt 150, thereby transferring the toner image formed on the intermediate transfer belt 150 onto the recording medium P. A transfer roller 152 is provided to face the backup roller 150C.

  Below the intermediate transfer belt 150, a recording medium supply device 153 that supplies the recording medium P to the secondary transfer roller 152 and a recording medium P on which a toner image is formed on the secondary transfer roller 152 are conveyed. Fixing means 180 for fixing the toner image is provided.

  The recording medium supply device 153 includes a pair of conveying rollers 153A and a guide slope 153B that guides the recording medium P conveyed by the conveying rollers 153A toward the secondary transfer roller 152. On the other hand, the fixing unit 180 includes a fixing roller 181 that is a pair of heat rollers for fixing the toner image by heating and pressing the recording medium P on which the toner image has been transferred by the secondary transfer roller 152, and fixing. A conveyance conveyor 182 that conveys the recording medium P toward the roller 181.

  The recording medium P is conveyed in the direction indicated by the arrow c by the recording medium supply device 153, the secondary transfer roller 152, and the fixing unit 180.

  Around the intermediate transfer belt 150, an intermediate transfer member cleaning unit 154 having a cleaning blade for removing toner remaining on the intermediate transfer belt 150 after the toner image is transferred to the recording medium P by the secondary transfer roller 152 is provided. It has been.

  Hereinafter, the developing unit 140 will be described in detail. The developing unit 140 is disposed in the developing region so as to face the electrostatic latent image holding member 110, and includes, for example, a toner charged to a negative (−) polarity and a carrier charged to a positive (+) polarity. A developer accommodating container 141 for accommodating the component developer is included. The developer container 141 includes a developer container main body 141A and a developer container cover 141B that closes the upper end of the developer container main body 141A.

  The developer container main body 141A has a developing roll chamber 142A for storing the developing roll 142 therein, and is adjacent to the first stirring chamber 143A and the first stirring chamber 143A adjacent to the developing roll chamber 142A. 144A of 2nd stirring chambers. In the developing roll chamber 142A, a layer thickness regulating member 145 for regulating the layer thickness of the developer on the surface of the developing roll 142 when the developer containing container cover 141B is mounted on the developer containing container main body 141A. Is provided.

  The first stirring chamber 143A and the second stirring chamber 144A are partitioned by a partition wall 141C. Although not shown, the longitudinal direction of the partition wall 141C of the first stirring chamber 143A and the second stirring chamber 144A (developing device) (Longitudinal direction) Both ends are provided with passages, and the first stirring chamber 143A and the second stirring chamber 144A constitute a circulation stirring chamber (143A + 144A).

  The developing roll 142 is disposed in the developing roll chamber 142A so as to face the electrostatic latent image holding body 110. Although not shown, the developing roll 142 is provided with a sleeve outside a magnetic roll (fixed magnet) having magnetism. The developer in the first stirring chamber 143A is adsorbed on the surface of the developing roll 142 by the magnetic force of the magnetic roll and is transported to the developing area. Further, the roll axis of the developing roll 142 is rotatably supported by the developer container main body 141A. Here, the developing roll 142 and the electrostatic latent image holding body 110 rotate in the opposite directions, and the developer adsorbed on the surface of the developing roll 142 at the facing portion advances by the electrostatic latent image holding body 110. The sheet is conveyed to the development area from the same direction as the direction.

  A bias power supply (not shown) is connected to the sleeve of the developing roll 142 so that a predetermined developing bias is applied (in this embodiment, an alternating electric field is applied to the developing region. , Applying a bias in which the AC component (AC) is superimposed on the DC component (DC)).

  The first stirring chamber 143A and the second stirring chamber 144A are provided with a first stirring member 143 (stirring / conveying member) and a second stirring member 144 (stirring / conveying member) that transport the developer while stirring. The first agitating member 143 includes a first rotating shaft extending in the axial direction of the developing roll 142, and an agitating / conveying blade (protrusion) fixed in a spiral manner on the outer periphery of the rotating shaft. Similarly to the first stirring member 143, the second stirring member 144 is also configured by a second rotating shaft and a stirring / conveying blade (protrusion). The stirring member is rotatably supported by the developer container main body 141A. The first stirring member 143 and the second stirring member 144 are arranged such that the developer in the first stirring chamber 143A and the second stirring chamber 144A is conveyed in the opposite directions by rotation thereof. .

One end of a developer supply means 146 for appropriately supplying a supply developer including supply toner and a supply carrier to the second agitation chamber 144A is connected to one end side in the longitudinal direction of the second agitation chamber 144A. The developer supply means 146 is connected to a developer cartridge 147 containing a supply developer.
As described above, the developing unit 140 appropriately supplies the supply developer from the developer cartridge 147 through the developer supplying unit 146 to the developing unit 140 (second stirring chamber 144A).

  Here, in this embodiment, the configuration using the developer cartridge 147 containing the supply developer of the present invention has been described as an example. However, the developer cartridge 147 is a toner cartridge that contains supply toner alone. And a carrier cartridge that individually stores the carrier for supply may be separated.

  Next, the cleaning unit 170 will be described in detail. The cleaning unit 170 includes a housing 171 and a cleaning blade 172 disposed so as to protrude from the housing 171. The cleaning blade 172 is a plate-like member extending in the extending direction of the rotation axis of the electrostatic latent image holding body 110, and is rotated in the rotation direction (arrow) from the transfer position by the primary transfer roller 151 in the electrostatic latent image holding body 110. a direction) A tip end portion (hereinafter referred to as an edge portion) is provided in pressure contact with the downstream side and the downstream side in the rotational direction from the position where the charge is removed by the charge removal means 160.

  The cleaning blade 172 is not transferred onto the intermediate transfer belt 150 by the primary transfer roller 151 by rotating the electrostatic latent image holding body 110 in a predetermined direction (arrow a direction). Foreign matter such as retained untransferred residual toner and paper dust of the recording medium P is dammed and removed from the electrostatic latent image holder 110.

  Further, a transport member 173 is disposed at the bottom of the housing 171, and toner particles (developer) removed by the cleaning blade 172 are developed on the downstream side of the transport direction of the transport member 173 in the housing 171 by the developing unit 140. One end of a supply conveying means 174 for supplying to is connected. The other end of the supply / conveyance unit 174 is connected to join the developer supply unit 146.

  As described above, the cleaning unit 170 transports the untransferred residual toner particles to the developing unit 140 (second stirring chamber 144A) through the supply transport unit 174 in accordance with the rotation of the transport member 173 provided at the bottom of the housing 171. A toner reclaim system is employed in which the developer (toner) contained in the container is stirred and conveyed for reuse.

-Latent image carrier-
Next, a latent image holding body (image holding body) constituting the image forming apparatus in the present embodiment will be described.
As the image carrier, a known photoreceptor (electrophotographic photoreceptor) having at least a photosensitive layer on a conductive support is used, but an organic photoreceptor is preferably used. In this case, the layer constituting the outermost surface of the image carrier, for example, the protective layer, preferably contains a resin having a crosslinked structure. As the resin having a crosslinked structure, for example, a phenol resin, a urethane resin, and a siloxane resin are used, and a siloxane resin and a phenol resin are most preferable.

In the present embodiment, it is preferable that the layer constituting the outermost surface of the image carrier includes a resin having a three-dimensional crosslinked structure. Since the layer constituting the outermost surface containing a resin having a three-dimensional crosslinked structure has high strength, it has high durability against wear and scratches, and the image carrier has a long life. However, since the surface of the holding body is hard to wear, it has a drawback that it is difficult to remove the adhered toner component.
On the other hand, in order to ensure the cleaning property, for example, when the cleaning blade is brought into contact with the image carrier at a high contact pressure, the torque is increased at the contact portion between the cleaning blade and the image carrier and the image is held. The toner remaining on the body surface may be easily destroyed. Further, when the toner is destroyed, the toner constituent material may adhere to the surface of the image holding member, and the charge fluctuation may easily occur. However, since the toner according to the exemplary embodiment has high durability and excellent strength, filming on the surface of the image carrier due to destruction of the toner and charging fluctuation associated therewith are suppressed. Further, even when combined with a method of recycling and reusing toner, the durability of the toner is high, so that an image with good image quality can be formed over a long period of time.

Note that the three-dimensional crosslinked structure of the resin contained in the surface protective layer is observed as follows.
Regarding the elements peculiar to the surface layer, ion etching was performed for 180 seconds under the conditions of an acceleration voltage of 400 ± 10 V and a degree of vacuum (3 ± 1) × 10 ⁻² Pa in an Ar atmosphere, and the surface was subjected to X-ray photoelectron analysis. It can be judged from the difference in the abundance (Atom%) of the specific element. It can be judged that the smaller the difference is, the stronger and more uniform the crosslinked structure of the surface protective layer is. Specific elements include, for example, Si, Ti, Al, and the like, and other elements C, O, N, etc. that form a protective layer by having a crosslinked structure are also made uniform in the depth direction. , Value fluctuations are small. In the present embodiment, the surface protective layer of the latent image holding member “contains a three-dimensional crosslinked structure” means that the difference between the abundance before ion etching and the abundance after ion etching is within 10%. Say.

  The layer structure of the image carrier is not particularly limited as long as it includes a conductive support and a photosensitive layer provided on the conductive support. Preferably, the photosensitive layer is a charge generation layer. It is preferably a function-separated type image carrier comprising a charge transport layer. Specifically, an undercoat layer, a charge generation layer, a charge transport layer, and a protective layer are laminated in this order on the surface of a conductive substrate. Preferably there is. Details of each layer will be described below.

  Examples of the conductive support include a metal plate, a metal drum, a metal belt, or a conductive metal using a metal or an alloy such as aluminum, copper, zinc, stainless steel, chromium, nickel, molybdenum, vanadium, indium, gold, or platinum. Examples thereof include paper, plastic film, belt and the like coated, vapor-deposited, or laminated with a polymer, a conductive compound such as indium oxide, or a metal or alloy such as aluminum, palladium, or gold.

When the image carrier is used in a laser printer, the laser oscillation wavelength is preferably from 350 nm to 850 nm, and the shorter wavelength is preferable because the resolution is excellent. In order to prevent interference fringes generated when laser light is irradiated, the surface of the support is preferably roughened to a centerline average roughness Ra of 0.04 μm or more and 0.5 μm or less. As a roughening method, wet honing is performed by suspending an abrasive in water and spraying on the support, or centerless grinding in which the support is pressed against a rotating grindstone and grinding is performed continuously, an anode Preference is given to oxidation, treatment with an acidic treatment liquid, boehmite treatment, production of a layer containing organic or inorganic semiconductive particles, and the like.
If Ra is smaller than 0.04 μm, it becomes close to a mirror surface, so that the effect of preventing interference cannot be obtained. If Ra is larger than 0.5 μm, even if a film is formed, the image quality may become rough and unsuitable. When non-interfering light is used for the light source, it is not particularly necessary to roughen the interference fringes, and it is possible to prevent the occurrence of defects due to the unevenness of the surface of the base material, which is suitable for longer life.

  The anodizing treatment is to form an oxide film on the aluminum surface by anodizing in an electrolyte solution using aluminum as an anode. Examples of the electrolyte solution include a sulfuric acid solution and an oxalic acid solution. However, the intact porous anodic oxide film is chemically active, easily contaminated, and has a large resistance fluctuation due to the environment. Therefore, the pores in the anodized film are sealed with pressurized water vapor or boiling water (a metal salt such as nickel may be added) by volume expansion due to a hydration reaction, and a sealing process is performed to change to a more stable hydrated oxide. . The thickness of the anodized film is preferably 0.3 μm or more and 15 μm or less. When it is thinner than 0.3 μm, the barrier property against injection is poor and the effect is not sufficient. On the other hand, if it is thicker than 15 μm, the residual potential increases due to repeated use.

The treatment with an acidic treatment liquid comprising phosphoric acid, chromic acid and hydrofluoric acid is carried out as follows, for example. The mixing ratio of phosphoric acid, chromic acid and hydrofluoric acid in the acidic treatment liquid is such that phosphoric acid is in the range of 10% by mass to 11% by mass, chromic acid is in the range of 3% by mass to 5% by mass, and hydrofluoric acid is 0%. The concentration of these acids is preferably in the range of 13.5% by mass to 18% by mass.
The treatment temperature is preferably 42 ° C. or more and 48 ° C. or less. However, by keeping the treatment temperature high, a thicker film can be formed faster. The film thickness is preferably from 0.3 μm to 15 μm. When it is thinner than 0.3 μm, the barrier property against injection is poor and the effect is not sufficient. On the other hand, if it is thicker than 15 μm, the residual potential increases due to repeated use.

  The boehmite treatment is performed, for example, by immersing in pure water at 90 ° C. or higher and 100 ° C. for 5 minutes to 60 minutes or by contacting with heated steam at 90 ° C. or higher and 120 ° C. or lower for 5 minutes to 60 minutes. The film thickness is preferably 0.1 μm or more and 5 μm or less. This can be further anodized using an electrolyte solution with low film solubility such as adipic acid, boric acid, borate, phosphate, phthalate, maleate, benzoate, tartrate, citrate. Good.

  Examples of organic or inorganic semiconductive particles include organic pigments such as perylene pigments, bisbenzimidazole perylene pigments, polycyclic quinone pigments, indigo pigments, and quinacridone pigments described in JP-A-47-30330. Organic pigments such as bisazo pigments and phthalocyanine pigments having electron-withdrawing substituents such as nitro groups, nitro groups, nitroso groups and halogen atoms, and inorganic pigments such as zinc oxide, titanium oxide and aluminum oxide. Among these pigments, zinc oxide and titanium oxide are preferable because they have a high charge transport ability and are effective for thickening.

  The surface of these pigments may be surface-treated with an organic titanium compound such as a titanate coupling agent, an aluminum chelate compound or an aluminum coupling agent for the purpose of improving dispersibility or adjusting the energy level, and in particular vinyltrichlorosilane. , Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-2-methoxyethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ -Chloropropyltrimethoxysilane, γ-2-aminoethylaminopropyltrimethoxysilane, γ-mercapropropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, β-3,4-epoxycyclo It is preferable to treat with a silane coupling agent such as hexyltrimethoxysilane.

If there are too many organic or inorganic semiconductive particles, the strength of the undercoat layer decreases and a coating film defect occurs. Therefore, the content of the semiconductive particles contained in the undercoat layer is preferably 95% by mass or less, 90 mass% or less is more preferable. As a method for mixing / dispersing organic or inorganic semiconductive particles, a method using a ball mill, a roll mill, a sand mill, an attritor, an ultrasonic wave, or the like is applied. Mixing / dispersing is performed in an organic solvent.
Any organic solvent may be used as long as it dissolves a fixed metal compound or resin and does not cause gelation or aggregation when organic / inorganic semiconductive particles are mixed / dispersed.
For example, methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene Ordinary organic solvents such as toluene are used alone or in admixture of two or more.

An undercoat layer may be formed between the conductive support and the photosensitive layer as necessary.
Examples of materials used for forming the undercoat layer include organic zirconium compounds such as zirconium chelate compounds, zirconium alkoxide compounds and zirconium coupling agents, organic titanium compounds such as titanium chelate compounds, titanium alkoxide compounds and titanate coupling agents, aluminum In addition to organoaluminum compounds such as chelate compounds and aluminum coupling agents, antimony alkoxide compounds, germanium alkoxide compounds, indium alkoxide compounds, indium chelate compounds, manganese alkoxide compounds, manganese chelate compounds, tin alkoxide compounds, tin chelate compounds, aluminum silicon alkoxides Compound, aluminum titanium alkoxide compound, aluminum zirconium alloy Kokishido compounds include organometallic compounds such as, in particular an organic zirconium compound, an organic titanyl compound, since the organic aluminum compound to residual potential indicates a satisfactory electrophotographic properties lower, are preferably used.

  The undercoat layer may be, for example, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-2-methoxyethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacrylate. Roxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-2-aminoethylaminopropyltrimethoxysilane, γ-mercapropropyltrimethoxysilane, γ-ureidopropyltriethoxysilane A silane coupling agent such as β-3,4-epoxycyclohexyltrimethoxysilane may be contained.

  Furthermore, for the undercoat layer, for example, polyvinyl alcohol, polyvinyl methyl ether, poly-N-vinyl imidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, polyamide, polyimide, casein, gelatin, polyethylene, Known binder resins such as polyester, phenol resin, vinyl chloride-vinyl acetate copolymer, epoxy resin, polyvinyl pyrrolidone, polyvinyl pyridine, polyurethane, polyglutamic acid, and polyacrylic acid may be used.

Further, an electron transporting pigment may be mixed and dispersed in the undercoat layer. Examples of the electron transport pigment include organic pigments such as perylene pigment, bisbenzimidazole perylene pigment, polycyclic quinone pigment, indigo pigment, and quinacridone pigment described in JP-A-47-30330, and cyano group and nitro group. And organic pigments such as bisazo pigments and phthalocyanine pigments having electron-withdrawing substituents such as nitroso groups and halogen atoms, and inorganic pigments such as zinc oxide and titanium oxide.
Among these pigments, perylene pigments, bisbenzimidazole perylene pigments and polycyclic quinone pigments, zinc oxide, and titanium oxide are preferably used because of their high electron mobility. In addition, the surface of these pigments may be surface-treated with the above-mentioned coupling agent or binder for the purpose of controlling dispersibility and charge transportability. If the amount of the electron transporting pigment is too large, the strength of the undercoat layer is lowered and a coating film defect is caused.

As a method for mixing and dispersing the electron transport pigment in the undercoat layer, for example, a conventional method using a ball mill, a roll mill, a sand mill, an attritor, an ultrasonic wave, or the like is applied. Mixing and dispersion are performed in an organic solvent.
Any organic solvent may be used as long as it dissolves a periodical metal compound or resin and does not cause gelation or aggregation when an electron transporting pigment is mixed and dispersed. Specific examples of the organic solvent include methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, and tetrahydrofuran. Ordinary organic solvents such as methylene chloride, chloroform, chlorobenzene and toluene may be used, and these may be used alone or in combination of two or more.

In general, the thickness of the undercoat layer is preferably from 0.1 μm to 30 μm, more preferably from 0.2 μm to 25 μm.
In addition, as a coating method used when providing the undercoat layer, for example, a normal method such as a blade coating method, a Meyer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, etc. Is used. The applied layer is dried to obtain an undercoat layer. Usually, the drying is performed at a temperature at which the solvent is evaporated to form a film. In particular, the base material subjected to the acidic solution treatment and the boehmite treatment is preferably formed with an intermediate layer because the defect concealing power of the base material tends to be insufficient.

Next, the charge generation layer will be described.
The charge generation material used for forming the charge generation layer is, for example, an azo pigment such as bisazo or trisazo, a condensed aromatic pigment such as dibromoanthanthrone, an organic pigment such as a perylene pigment, a pyrrolopyrrole pigment, or a phthalocyanine pigment, or a trigonal crystal. Although all known ones such as inorganic pigments such as selenium and zinc oxide are used, inorganic pigments are particularly preferred when using an exposure wavelength of 380 nm to 500 nm, and metals and non-organic pigments are used when using an exposure wavelength of 700 nm to 800 nm. Metal phthalocyanine pigments are preferred. Among these, hydroxygallium phthalocyanine disclosed in JP-A-5-263007 and JP-A-5-279951, chlorogallium phthalocyanine disclosed in JP-A-5-98181, JP-A-5-140472 and Of these, dichlorotin phthalocyanine disclosed in JP-A-5-140473, titanyl phthalocyanine disclosed in JP-A-4-189873 and JP-A-5-43813 are particularly preferable.

The binder resin used for forming the charge generation layer is selected from a wide range of insulating resins (herein, “insulating” means, for example, a volume resistivity of 10 ¹³ Ωcm or more), and a poly- You may select from organic photoconductive polymers, such as N-vinyl carbazole, polyvinyl anthracene, polyvinyl pyrene, polysilane. Preferred binder resins include, for example, polyvinyl butyral resin, polyarylate resin (polycondensate of bisphenol A and phthalic acid, etc.), polycarbonate resin, polyester resin, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyamide resin, acrylic resin, etc. Examples thereof include, but are not limited to, resins, polyacrylamide resins, polyvinyl pyridine resins, cellulose resins, urethane resins, epoxy resins, caseins, polyvinyl alcohol resins, and polyvinyl pyrrolidone resins. These binder resins may be used alone or in combination of two or more.

  The blending ratio of the charge generation material and the binder resin (mass ratio) is preferably in the range of 10: 1 to 1:10. In addition, as a method for dispersing these, usual methods such as a ball mill dispersion method, an attritor dispersion method, a sand mill dispersion method, and the like are used. In this case, conditions under which the crystal type does not change by dispersion are desirable. Furthermore, it is preferable that the particle size be 0.5 μm or less during the dispersion.

  Examples of the solvent used for dispersion include methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, Usual organic solvents such as tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, toluene and the like can be used alone or in admixture of two or more.

  The thickness of the charge generation layer is generally preferably 0.1 μm or more and 5 μm or less. Further, as a coating method used when providing the charge generation layer, for example, a usual method such as a blade coating method, a Meyer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, etc. Is used.

Next, the charge transport layer will be described.
As the charge transport layer, a layer formed by a known technique is used. These charge transport layers are formed containing a charge transport material and a binder resin, or are formed containing a polymer charge transport material.
Examples of charge transport materials include quinone compounds such as p-benzoquinone, chloranil, bromanyl, anthraquinone, tetracyanoquinodimethane compounds, fluorenone compounds such as 2,4,7-trinitrofluorenone, xanthone compounds, and benzophenone compounds. Compounds, electron transport compounds such as cyanovinyl compounds, ethylene compounds, triarylamine compounds, benzidine compounds, arylalkane compounds, aryl-substituted ethylene compounds, stilbene compounds, anthracene compounds, hydrazone compounds, etc. A hole transporting compound may be mentioned. These charge transport materials may be used alone or in combination of two or more, but are not limited thereto.

  Examples of the binder resin used for the charge transport layer include polycarbonate resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl acetate resin, styrene-butadiene copolymer, and vinylidene chloride. Acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N- Polymeric charge transport materials such as vinyl carbazole, polysilane, and polyester-based polymer charge transport materials disclosed in JP-A-8-176293 and JP-A-8-208820 are used. These binder resins may be used alone or in combination of two or more. The blending ratio (mass ratio) of the charge transport material and the binder resin is preferably 10: 1 to 1: 5.

  Moreover, you may use a polymeric charge transport material independently for formation of a charge transport layer. As the polymer charge transporting material, known materials having charge transporting properties such as poly-N-vinylcarbazole and polysilane are used. In particular, polyester polymer charge transport materials disclosed in JP-A-8-176293 and JP-A-8-208820 have a high charge transporting property and are particularly preferable. The polymer charge transporting material alone is used as a charge transporting layer, but may be mixed with the binder resin to form a film.

The thickness of the charge transport layer is generally preferably 5 μm or more and 50 μm or less, and more preferably 10 μm or more and 30 μm or less.
As a coating method, for example, a usual method such as a blade coating method, a Mayer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, or the like is used. Furthermore, examples of the solvent used when the charge transport layer is provided include aromatic hydrocarbons such as benzene, toluene, xylene and chlorobenzene, ketones such as acetone and 2-butanone, and halongen such as methylene chloride, chloroform and ethylene chloride. Ordinary organic solvents such as cyclic aliphatic hydrocarbons, cyclic ethers such as tetrahydrofuran and ethyl ether, or straight-chain ethers may be used alone or in combination of two or more.

  In addition, additives such as antioxidants, light stabilizers, and heat stabilizers are added to the photosensitive layer for the purpose of preventing deterioration of the image carrier due to ozone, oxidizing gas, or light or heat generated in the copying machine. It may be added. For example, examples of the antioxidant include hindered phenol, hindered amine, paraphenylenediamine, arylalkane, hydroquinone, spirochroman, spiroidanone and derivatives thereof, organic sulfur compounds, and organic phosphorus compounds. Examples of the light stabilizer include derivatives such as benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine.

Further, at least one kind of electron accepting substance may be contained for the purpose of improving sensitivity, reducing residual potential, reducing fatigue during repeated use, and the like. Examples of the electron acceptor used for the image carrier include succinic anhydride, maleic anhydride, dibromomaleic anhydride, phthalic anhydride, tetrabromophthalic anhydride, tetracyanoethylene, tetracyanoquinodimethane, and o-dioxide. Examples include nitrobenzene, m-dinitrobenzene, chloranil, dinitroanthraquinone, trinitrofluorenone, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, phthalic acid and the like. Of these, benzene derivatives having an electron-withdrawing substituent such as fluorenone, quinone, Cl, CN, and NO ₂ are particularly preferable.

Next, the protective layer (layer constituting the outermost surface) will be described.
It is desirable to provide a high-strength protective layer in order to give the protective layer resistance to abrasion and scratches. As this high-strength protective layer, conductive particles are dispersed in a binder resin, lubricating particles such as fluororesin and acrylic resin are dispersed in a normal charge transport layer material, silicone, acrylic, etc. A hard coating agent is used, but from the viewpoint of strength, electrical characteristics, image quality maintenance, etc., those having a crosslinked structure are preferred, and those containing a charge transporting material are more preferred. Various materials are used for forming the crosslinked structure, but phenolic resins, urethane resins, siloxane resins, and the like are preferable in terms of characteristics, and those made of siloxane resins and phenolic resins are particularly preferable.

  In particular, in this embodiment, it is preferable that the protective layer includes a siloxane resin having a crosslinked structure. A protective layer containing a siloxane-based resin has excellent thermal and mechanical strength and reduces image quality deterioration due to wear of the protective layer, but on the other hand, the discharge product is difficult to remove, and the discharge product absorbs moisture. The resulting image flow is likely to occur. However, according to the present embodiment, even when an image carrier having a protective layer containing such a resin and having excellent mechanical strength is used, the image carrier is caused by deposits such as discharge products that adhere to the surface of the image carrier. Image quality defects are sufficiently suppressed, and a high-quality image is formed over an extremely long period of time.

  Regarding the resin constituting the protective layer, those having a structure derived from the compounds represented by the general formulas (I) and (II) are particularly preferred because of their excellent strength and stability.

F- [D-Si (R ² ) _(3-a) Q _a ] _b (I)
In general formula (I), F is an organic group derived from a compound having a hole transporting ability, D is a flexible subunit, R ² is hydrogen, an alkyl group, a substituted or unsubstituted aryl group, and Q is a hydrolyzed group. Represents a decomposable group, a represents an integer of 1 to 3, and b represents an integer of 1 to 4.
The flexible subunit represented by D in the general formula (I) necessarily includes a — (CH ₂ ) _n — group, which includes —COO—, —O—, —CH═CH—, — It may be a divalent linear group in which a CH═N— group is combined. Note that _{n in the} — (CH ₂ ) _n — group represents an integer of 1 to 5. Moreover, as a hydrolysable group represented by Q, -OR group (however, R represents an alkyl group) is represented.

F-((X) _p R ¹ -ZH) _m (II)
In general formula (II), F is an organic group derived from a compound having a hole transporting ability, R ¹ is an alkylene group, Z is —O—, —S—, —NH—, or —COO—, m represents an integer of 1 or more and 4 or less. X represents —O— or —S—, and p represents 0 or 1.
Further, more preferable examples of the compound represented by the general formula (I) include those represented by the following general formula (III).

In general formula (III), Ar ^{1 to} Ar ⁴ each independently represent a substituted or unsubstituted aryl group, Ar ⁵ represents a substituted or unsubstituted aryl group or arylene group, and Ar ¹ to Ar 2 to 4 of ⁵ have a bond represented by —D—Si (R ² ) _(3-a) Q _a in the general formula (I). D represents a flexible subunit, R ² represents hydrogen, an alkyl group, a substituted or unsubstituted aryl group, Q represents a hydrolyzable group, and a represents an integer of 1 to 3. K represents 0 or 1.

Ar ^{1 to} Ar ⁴ in the general formula (III) each independently represent a substituted or unsubstituted aryl group, and specifically, those shown in the following structural group 1 are preferable.

  In addition, Ar shown in the structure group 1 is preferably selected from the following structure group 2, and Z ′ is preferably selected from the following structure group 3.

In Structural Groups 1 to 3, R ⁶ is hydrogen, a phenyl group substituted with an alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, or It is selected from an unsubstituted phenyl group and an aralkyl group having 7 to 10 carbon atoms.
R ^{7 to} R ¹³ are hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group substituted with an alkoxy group having 1 to 4 carbon atoms, or unsubstituted It is selected from a phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen.
m and s represent 0 or 1, q and r represent an integer of 1 to 10, and t represents an integer of 1 to 3. Here, X represents a group represented by —D—Si (R ² ) _(3-a) Q _a shown in the general formula (I).
Further, W shown in the structure group 3 is preferably that shown in the following structure group 4. In the structure group 4, s ′ represents an integer of 0 or more and 3 or less.

In order to control various physical properties such as strength and film resistance, a compound represented by the following general formula (IV) may be added.
Si (R ² ) _(4-c) Q _c (IV)
In general formula (IV), R ² represents hydrogen, an alkyl group, a substituted or unsubstituted aryl group, Q represents a hydrolyzable group, and c represents an integer of 1 to 4.

Specific examples of the compound represented by the general formula (IV) include silane coupling agents exemplified below.
Specifically, for example, tetrafunctional alkoxysilanes such as tetramethoxysilane and tetraethoxysilane (c = 4); methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, methyltrimethoxyethoxysilane, vinyltri Methoxysilane, vinyltriethoxysilane, phenyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxy Silane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, (tridecafluoro-1,1,2,2-tetrahydrooctyl) trie Toxisilane, (3,3,3-trifluoropropyl) trimethoxysilane, 3- (heptafluoroisopropoxy) propyltriethoxysilane, 1H, 1H, 2H, 2H-perfluoroalkyltriethoxysilane, 1H, 1H, Trifunctional alkoxysilanes (c = 3) such as 2H, 2H-perfluorodecyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane; dimethyldimethoxysilane, diphenyldimethoxysilane, methylphenyl And bifunctional alkoxysilanes such as dimethoxysilane (c = 2); monofunctional alkoxysilanes such as trimethylmethoxysilane (c = 1), and the like. Tri- and tetrafunctional alkoxysilanes are preferable for improving the strength of the film, and bi- and monofunctional alkoxysilanes are preferable for improving flexibility and film-forming properties.

  Further, silicone-based hard coating agents prepared mainly from these coupling agents are also used. Commercially available hard coat agents include KP-85, X-40-9740, X-40-2239 (manufactured by Shin-Etsu Silicone), and AY42-440, AY42-441, AY49-208 (manufactured by Toray Dow Corning). Etc.) are used.

In order to increase the strength, it is also preferable to use a compound having two or more silicon atoms represented by the general formula (V).
B- (Si (R ² ) _(3-a) Q _a ) ₂ (V)
In general formula (V), B represents a divalent organic group, R ² represents hydrogen, an alkyl group, a substituted or unsubstituted aryl group, Q represents a hydrolyzable group, and a represents an integer of 1 to 3. .

  Further, for example, a resin soluble in an alcohol solvent or a ketone solvent may be added in order to control the film characteristics and extend the life of the liquid. Examples of this resin include polyvinyl acetal resins such as polyvinyl butyral resin, polyvinyl formal resin, and partially acetalized polyvinyl acetal resin in which a part of butyral is modified with formal or acetoacetal (for example, manufactured by Sekisui Chemical Co., Ltd.). ESREC B, K, etc.), polyamide resin, cellulose resin, phenol resin and the like. In particular, polyvinyl acetal resin is preferable in terms of electrical characteristics.

Various resins may be added for the purpose of discharge gas resistance, mechanical strength, scratch resistance, particle dispersibility, viscosity control, torque reduction, wear amount control, pot life extension, and the like. Particularly in the case of a siloxane-based resin, it is preferable to add a resin that dissolves in alcohol.
Examples of resins that are soluble in alcohol solvents include polyvinyl butyral resins, polyvinyl formal resins, and polyvinyl acetal resins such as partially acetalized polyvinyl acetal resins in which a part of butyral is modified with formal or acetoacetal (for example, Sekisui Chemical Co., Ltd. S-Rec B, K, etc.), polyamide resin, cellulose resin, phenol resin, etc. In particular, polyvinyl acetal resin is preferable in terms of electrical characteristics.

  The molecular weight of the resin is preferably from 2,000 to 100,000, and more preferably from 5,000 to 50,000. If the molecular weight is less than 2,000, the desired effect cannot be obtained. If the molecular weight is more than 100,000, the solubility becomes low and the addition amount may be limited, or the film formation may be poor at the time of coating. The addition amount is preferably 1% by mass to 40% by mass, more preferably 1% by mass to 30% by mass, and most preferably 5% by mass to 20% by mass. When the amount is less than 1% by mass, it is difficult to obtain a desired effect. When the amount is more than 40% by mass, image blurring under high temperature and high humidity tends to occur. These resins may be used alone or in combination.

  Further, for the purpose of extending the pot life and controlling the film properties, a cyclic compound having a repeating structural unit represented by the following general formula (VI) or a derivative thereof can be contained.

In general formula (VI), A ¹ and A ² each independently represent a monovalent organic group.
A commercially available cyclic siloxane is mentioned as a cyclic compound which has a repeating structural unit shown by general formula (VI). Specifically, for example, cyclic dimethylcyclosiloxanes such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, 1,3,5-trimethyl-1,3,5 -Triphenylcyclotrisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetraphenylcyclotetrasiloxane, 1,3,5,7,9-pentamethyl-1,3,5, Cyclic methylphenylcyclosiloxanes such as 7,9-pentaphenylcyclopentasiloxane, cyclic phenylcyclosiloxanes such as hexaphenylcyclotrisiloxane, 3- (3,3,3-trifluoropropyl) methylcyclotrisiloxane, etc. Fluorine-containing cyclosiloxanes, methylhydrosiloxy Down mixture, pentamethylcyclopentasiloxane, hydrosilyl group-containing cyclosiloxanes such as phenyl hydrocyclosiloxane include a cyclic siloxane such as a vinyl group-containing cyclosiloxanes, such as penta vinyl pentamethylcyclopentasiloxane like. These cyclic siloxane compounds may be used alone or in combination.

  Furthermore, it is desirable to add various particles in order to improve the antifouling substance adhesion and lubricity on the surface of the image carrier. These particles may be used alone or in combination. An example of the particles is silicon-containing particles. Silicon-containing particles are particles containing silicon as a constituent element, and specific examples include colloidal silica and silicone particles. The colloidal silica used as the silicon-containing particles preferably has an average particle size of 1 nm or more and 100 nm or less, more preferably 10 nm or more and 30 nm or less, and is dispersed in an acidic or alkaline aqueous dispersion or an organic solvent such as alcohol, ketone, or ester. A commercially available product is used. The solid content of colloidal silica in the outermost surface layer is not particularly limited, but it is 0.1% by mass or more in the total solid content of the outermost surface layer in terms of film forming properties, electrical characteristics, and strength. The range of mass% or less is preferable, and the range of 0.1 mass% or more and 30 mass% or less is more preferable.

Silicone particles used as silicon-containing particles are spherical and preferably have a volume average particle size of 1 nm to 500 nm, more preferably 10 nm to 100 nm, and are generally selected from silicone resin particles, silicone rubber particles, and silicone surface-treated silica particles. A commercially available product is used. Silicone particles are small particles that are chemically inert and have excellent dispersibility in the resin, and because the content required to obtain sufficient properties is low, the image can be obtained without inhibiting the crosslinking reaction. Improve the surface properties of the holder. That is, in a state of being uniformly incorporated into a strong cross-linked structure, the lubricity and water repellency of the surface of the image carrier are improved, and good wear resistance and contamination resistance adherence are maintained over a long period of time.
The content of the silicone particles in the outermost surface layer in the image carrier is preferably in the range of 0.1% by mass to 30% by mass in the total solid content of the outermost surface layer, and is 0.5% by mass to 10% by mass. The range of is more preferable.

As other particles, for example, fluorine-based particles such as ethylene tetrafluoride, ethylene trifluoride, propylene hexafluoride, vinyl fluoride, vinylidene fluoride, etc. As shown, particles made of a resin obtained by copolymerizing the fluororesin and a monomer having a hydroxyl group, ZnO—Al ₂ O ₃ , SnO ₂ —Sb ₂ O ₃ , In ₂ O ₃ —SnO ₂ , ZnO—TiO _2. , ZnO—TiO ₂ , MgO—Al ₂ O ₃ , FeO—TiO ₂ , TiO ₂ , SnO ₂ , In ₂ O ₃ , ZnO, MgO, and other semiconductive metal oxides.
Further, an oil such as silicone oil may be added for the purpose of lubricating the surface of the image carrier and improving volatility. Examples of the silicone oil include silicone oils such as dimethylpolysiloxane, diphenylpolysiloxane, and phenylmethylsiloxane, amino-modified polysiloxane, epoxy-modified polysiloxane, carboxyl-modified polysiloxane, carbinol-modified polysiloxane, methacryl-modified polysiloxane, and mercapto. Examples thereof include reactive silicone oils such as modified polysiloxane and phenol-modified polysiloxane.

  The exposure rate of the particles to the protective layer surface is preferably 40% or less. If the above range is exceeded, the influence of the particles alone becomes large, and image flow or the like due to low resistance tends to occur. A more preferable range within the above range is 30% or less, and the particles exposed on the surface are effectively refreshed by the cleaning member, and over a long period of time, suppression of toner component filming on the surface of the image carrier, removal of discharge products, A reduction in wear of the cleaning member due to a reduction in torque is maintained.

  Additives such as plasticizers, surface modifiers, antioxidants, and photodegradation inhibitors may be used. Examples of the plasticizer include biphenyl, biphenyl chloride, terphenyl, dibutyl phthalate, diethylene glycol phthalate, dioctyl phthalate, triphenyl phosphate, methyl naphthalene, benzophenone, chlorinated paraffin, polypropylene, polystyrene, and various fluorohydrocarbons.

  An antioxidant having a hindered phenol, hindered amine, thioether or phosphite partial structure is added to the protective layer, which is effective in improving the potential stability and image quality when the environment changes. Antioxidants include the compounds exemplified below, for example, “Sumizer BHT-R”, “Sumizer MDP-S”, “Sumizer BBM-S”, “Sumizer WX-R”, “Sumizer NW” as hindered phenols, "Sumilizer BP-76", "Sumilizer BP-101", "Sumilizer GA-80", "Sumilizer GM", "Sumizer GS" or more manufactured by Sumitomo Chemical; "IRGANOX1010", "IRGANOX1035", "IRGANOX1076" ”,“ IRGANOX1135 ”,“ IRGANOX1141 ”,“ IRGANOX1222 ”,“ IRGANOX1330 ”,“ IRGANOX “425WL”, “IRGANOX1520L”, “IRGANOX245”, “IRGANOX259”, “IRGANOX3114”, “IRGANOX3790”, “IRGANOX5057”, “IRGANOX565” or more manufactured by Ciba Specialty Chemicals Co., Ltd .; ”,“ ADK STAB AO-40 ”,“ ADK STAB AO-50 ”,“ ADK STAB AO-60 ”,“ ADK STAB AO-70 ”,“ ADK STAB AO-80 ”,“ ADK STAB AO-330 ”or more manufactured by Asahi Denka; As the amine system, “Sanol LS2626”, “Sanol LS765”, “Sanol LS770”, “Sanol LS744”, “Tinuvin 144”, “Tinuvin 622LD”, “Mark LA57” , “Mark LA67”, “Mark LA62”, “Mark LA68”, “Mark LA63”, “Smilizer-TPS”; “Smilizer-TP-D” as thioether system, “Mark 2112” as “phosphite system”, “Mark PEP” * 8, "Mark PEP.24G", "Mark PEP.36", "Mark 329K", "Mark HP.10"; hindered phenols and hindered amine antioxidants are particularly preferable. Furthermore, they may be modified with a substituent such as an alkoxysilyl group that undergoes a crosslinking reaction with the material forming the crosslinked film.

It is preferable to add or use a coating liquid used for forming the protective layer or a catalyst when preparing the coating liquid. Examples of the catalyst used include inorganic acids such as hydrochloric acid, acetic acid, phosphoric acid and sulfuric acid, organic acids such as formic acid, propionic acid, oxalic acid, paratoluenesulfonic acid, benzoic acid, phthalic acid and maleic acid, potassium hydroxide, water An alkali catalyst such as sodium oxide, calcium hydroxide, ammonia, triethylamine, or a solid catalyst insoluble in the system shown may be used.
For example, Amberlite 15, Amberlite 200C, Amberlist 15E (above, manufactured by Rohm and Haas); Dowex MWC-1-H, Dowex 88, Dowex HCR-W2 (above, Dow Chemical Co., Ltd.) ); Levacit SPC-108, Levacit SPC-118 (manufactured by Bayer); Diaion RCP-150H (Mitsubishi Kasei); Sumikaion KC-470, Duolite C26-C, Duolite C-433, Duolite -464 (above, manufactured by Sumitomo Chemical Co., Ltd.); cation exchange resin such as Nafion-H (produced by DuPont); Amberlite IRA-400, Amberlite IRA-45 (above, Rome and Hearth) Anion exchange resin such as Zr (O ₃ PCH ₂ CH ₂ SO ₃ H) ₂ , An inorganic solid in which a group containing a protonic acid group such as Th (O ₃ PCH ₂ CH ₂ COOH) ₂ is bonded to the surface; a polyorganosiloxane containing a protonic acid group such as a polyorganosiloxane having a sulfonic acid group; Heteropolyacids such as cobalt tungstic acid and phosphomolybdic acid; isopolyacids such as niobic acid, tantalum acid and molybdic acid; monometallic oxides such as silica gel, alumina, chromia, zirconia, CaO and MgO; silica-alumina, silica- Composite metal oxides such as magnesia, silica-zirconia, and zeolites; clay minerals such as acidic clay, activated clay, montmorillonite, and kaolinite; metal sulfates such as LiSO ₄ and MgSO ₄ ; zirconia phosphate, lanthanum phosphate, etc. Metal phosphate; LiNO ₃ , Mn (NO ₃ ) Metal nitrates such as ₂ ; inorganic solids having amino group-containing groups such as solids obtained by reacting aminopropyltriethoxysilane on silica gel; amino groups such as amino-modified silicone resins And polyorganosiloxane containing.

  Moreover, it is preferable to use a solid catalyst that is insoluble in a photofunctional compound, reaction product, water, solvent, or the like in the preparation of the coating liquid because the stability of the coating liquid tends to be improved. A solid catalyst that is insoluble in the system is particularly suitable if the catalyst component is insoluble in the compounds represented by the general formulas (I), (II), (III), (V), other additives, water, solvents, etc. It is not limited. The amount of these solid catalysts used is not particularly limited, but is preferably 0.1 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass in total of the compounds having hydrolyzable groups. Further, as described above, these solid catalysts are insoluble in raw material compounds, reaction products, solvents and the like, and therefore are easily removed after the reaction according to a conventional method. The reaction temperature and reaction time are selected according to the type and amount of the raw material compound or solid catalyst, but the reaction temperature is usually preferably 0 ° C. or higher and 100 ° C. or lower, more preferably 10 ° C. or higher and 70 ° C. or lower, The reaction temperature is more preferably 15 ° C. or more and 50 ° C. or less, and the reaction time is preferably 10 minutes to 100 hours. If the reaction time exceeds the upper limit, gelation tends to occur.

  When a catalyst that is insoluble in the system is used in the coating liquid preparation step, it is preferable to use a catalyst that is further dissolved in the system for the purpose of improving strength, liquid storage stability, and the like. As the catalyst, for example, aluminum triethylate, aluminum triisopropylate, aluminum tri (sec-butyrate), mono (sec-butoxy) aluminum diisopropylate, diisopropoxyaluminum (ethyl acetoacetate) Aluminum tris (ethyl acetoacetate), aluminum bis (ethyl acetoacetate) monoacetylacetonate, aluminum tris (acetylacetonate), aluminum diisopropoxy (acetylacetonate), aluminum isopropoxy-bis (acetylacetonate), Organo aluminum compounds such as aluminum tris (trifluoroacetylacetonate) and aluminum tris (hexafluoroacetylacetonate) It may be use.

  In addition to the organoaluminum compounds, for example, organotin compounds such as dibutyltin dilaurate, dibutyltin dioctiate, dibutyltin diacetate; titanium tetrakis (acetylacetonate), titanium bis (butoxy) bis (acetylacetonate), titanium Organic titanium compounds such as bis (isopropoxy) bis (acetylacetonate); zirconium tetrakis (acetylacetonate), zirconium bis (butoxy) bis (acetylacetonate), zirconium bis (isopropoxy) bis (acetylacetonate), etc. Zirconium compounds may also be used, but from the viewpoint of safety, low cost, and pot life length, it is preferable to use an organoaluminum compound, particularly an aluminum chelate compound. It is more preferable. Although the usage-amount of these catalysts is not restrict | limited in particular, 0.1 to 20 mass parts is preferable with respect to a total of 100 mass parts of the compound which has a hydrolysable group, 0.3 to 10 mass parts is preferable. Is particularly preferred.

  When an organometallic compound is used as a catalyst, it is preferable to add a multidentate ligand from the viewpoint of pot life and curing efficiency. Examples of the multidentate ligand include those exemplified below and those derived therefrom, but are not limited thereto.

Specifically, for example, β-diketones such as acetylacetone, trifluoroacetylacetone, hexafluoroacetylacetone, dipivaloylmethylacetone; acetoacetates such as methyl acetoacetate and ethyl acetoacetate; bipyridine and derivatives thereof; glycine and Derivatives thereof; ethylenediamine and derivatives thereof; 8-oxyquinoline and derivatives thereof; salicylaldehyde and derivatives thereof; catechol and derivatives thereof; bidentate ligands such as 2-oxyazo compounds; diethyltriamine and derivatives thereof; nitrilotriacetic acid and And tridentate ligands such as derivatives thereof; hexadentate ligands such as ethylenediaminetetraacetic acid (EDTA) and derivatives thereof; and the like. Furthermore, in addition to the above organic ligands, inorganic ligands such as pyrophosphoric acid and triphosphoric acid can be used. As the multidentate ligand, a bidentate ligand is particularly preferable, and specific examples include a bidentate ligand represented by the following general formula (VII) in addition to the above. Among them, a bidentate ligand represented by the following general formula (VII) is more preferable, and those in which R ⁵ and R ⁶ in the following general formula (VII) are the same are particularly preferable. By making R ⁵ and R ^{6 the} same, the coordination power of the ligand becomes stronger, and the coating liquid can be further stabilized.

In general formula (VII), R ⁵ and R ⁶ each independently represent an alkyl group having 1 to 10 carbon atoms, a fluorinated alkyl group, or an alkoxy group having 1 to 10 carbon atoms.
The compounding amount of the polydentate ligand is preferably 0.01 mol or more, more preferably 0.1 mol or more, and still more preferably 1 mol or more with respect to 1 mol of the organometallic compound used.
The coating solution may be produced in the absence of a solvent, but if necessary, for example, alcohols such as methanol, ethanol, propanol and butanol; ketones such as acetone and methyl ethyl ketone; tetrahydrofuran; ethers such as diethyl ether and dioxane In addition, various solvents are used. As the solvent, those having a boiling point of 100 ° C. or less are preferable, and they may be arbitrarily mixed and used. If the amount of the solvent is too small, the organosilicon compound is likely to precipitate. Therefore, the amount is preferably 0.5 parts by mass or more and 30 parts by mass or less, and preferably 1 part by mass or more and 20 parts by mass or less with respect to 1 part by mass of the organosilicon compound. More preferred.

  The reaction temperature and reaction time for curing the coating liquid are not particularly limited, but the reaction temperature is preferably 60 ° C. or higher, and 80 ° C. or higher, 200 ° C. from the viewpoint of mechanical strength and chemical stability of the resulting silicon resin. The following is more preferable, and the reaction time is preferably 10 minutes to 5 hours. In addition, maintaining the organic layer obtained by curing the coating liquid in a high humidity state is effective in stabilizing the characteristics of the organic layer. Furthermore, the organic layer may be subjected to a surface treatment using hexamethyldisilazane, trimethylchlorosilane, or the like according to the use to make it hydrophobic.

  On the other hand, as the phenolic resin, in addition to the above general formula, at least one charge transporting material selected from a hydroxyl group, a carboxyl group, an alkoxysilyl group, an epoxy group, a thiol group and an amino group (having a charge transporting ability). It is more preferable that it is a phenol-type resin containing the structural unit which has).

Examples of phenol derivatives used for the synthesis of phenolic resins include substituted phenols containing one hydroxyl group such as resorcin, bisphenol, phenol, cresol, xylenol, paraalkylphenol, paraphenylphenol, catechol, resorcinol, hydroquinone, etc. Compounds having a phenol structure such as substituted phenols containing two hydroxyl groups, bisphenols such as bisphenol A and bisphenol Z, and biphenols are used, and those that are generally commercially available as raw materials for synthesizing phenol resins are used. .
In addition, as the phenol derivative, for example, those containing a methylol group are also used, for example, monomers of monomethylolphenols, dimethylolphenols or trimethylolphenols, mixtures thereof, oligomerized thereof, or monomers thereof And a mixture of oligomers.
In the present specification, a relatively large molecule in which the number of repeating molecular structural units is about 2 or more and 20 or less is called an oligomer, and a molecule smaller than that is called a monomer.

  Moreover, as aldehydes used for the synthesis | combination of a phenol-type resin, formaldehyde, paraformaldehyde, etc. are utilized, for example. In synthesizing a phenolic resin, these raw materials can be obtained by reacting them in the presence of an acid catalyst or an alkali catalyst, but generally those commercially available as phenolic resins can also be used.

Examples of the acid catalyst include sulfuric acid, paratoluenesulfonic acid, phosphoric acid and the like. As the alkali catalyst, for example, hydroxides or amine catalysts of alkali metals and alkaline earth metals such as NaOH, KOH, Ca (OH) 2 and Ba (OH) 2 are used.
Examples of the amine catalyst include, but are not limited to, ammonia, hexamethylenetetramine, trimethylamine, triethylamine, triethanolamine, and the like.
When a basic catalyst is used, carriers are trapped by the remaining catalyst, and the electrophotographic characteristics may be deteriorated. For this reason, when a basic catalyst is used, after the reaction using the catalyst is completed, it must be neutralized with an acid, or deactivated or removed by contacting with an adsorbent such as silica gel, an ion exchange resin, or the like. Is preferred.

The phenolic resin having a crosslinked structure used for the image carrier may be one obtained by further crosslinking the above-mentioned known phenolic resin, and the phenolic resin itself has a crosslinked structure like a novolac type. It may be what you are doing. In the former case, it is more preferable to use a resol type phenol resin.
In particular, since the toner containing a crystalline resin has a hygroscopic property as in this embodiment, the surface layer has a longer period than that used in combination with a photoreceptor having the surface layer of the siloxane-based resin that is inferior in water absorption and gas barrier properties. It is more preferably used in that it can stably obtain high image quality.

  The protective layer having a charge transporting property and having a cross-linked structure described above has excellent mechanical strength and sufficient photoelectric properties. Therefore, it can be used as it is as a charge transport layer of a multilayer image carrier. Good. In this case, for example, a usual method such as a blade coating method, a Meyer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, or a curtain coating method is used. However, when a required film thickness cannot be obtained by a single application, the necessary film thickness can be obtained by applying a plurality of times. When performing multiple times of repeated application, the heat treatment may be performed every time of application, or after multiple times of repeated application.

In the case of a single-layer type photosensitive layer, it is formed containing the charge generating material and a binder resin. As the binder resin, those similar to the binder resin used for the charge generation layer and the charge transport layer are used. The content of the charge generating substance in the single-layer type photosensitive layer is preferably about 10% by mass to 85% by mass, and more preferably 20% by mass to 50% by mass.
A charge transport material or a polymer charge transport material may be added to the single-layer type photosensitive layer for the purpose of improving photoelectric characteristics. The addition amount is preferably 5% by mass or more and 50% by mass or less. Moreover, you may add the compound shown by general formula (I). The same solvent and coating method as those described above are used. The film thickness is preferably about 5 μm to 50 μm, and more preferably 10 μm to 40 μm.

The oxygen permeability of the protective layer is preferably 2500 fm / s · Pa or less.
Oxidized degradation products, etc., which have a problem of adhesion to the surface with a long-life photoconductor, are considered to be caused by, for example, NOx or ozone gas penetrating into the photosensitive layer and chemical degradation of a part of the photosensitive layer. . Therefore, as the gas permeation of the outermost surface layer hardly occurs, that is, as the oxygen permeability is lower, oxidation degradation products and the like are less likely to occur, which is advantageous for high image quality and long life.
A more preferable range of oxygen permeability of the outermost surface layer is 2000 fm / s · Pa or less, and a more preferable range is 1500 fm / s · Pa or less.

  The oxygen permeability represents the ease of oxygen gas permeation of the layer. Further, if the gas changes, the absolute value of the transmittance changes, but there is almost no reversal of the magnitude relationship between the layers serving as the specimens. Therefore, this may be interpreted as a general scale for expressing the ease of gas permeation. Since oxygen permeability is a measure of the ease of gas permeation, it can be considered as a substitute characteristic of the physical porosity of the layer if the view is changed. And in this embodiment, oxygen permeability is a value calculated | required as follows. A sample film is set between the sealed cells, both cells are evacuated, oxygen at a constant pressure (eg, 100 kPa) is sealed in one cell, and the amount of oxygen passing through the sample film is measured in the other cell. With the pressure sensor set to, read as pressure value and convert to oxygen amount.

<Process cartridge>
The process cartridge of this embodiment includes at least a developer holder, and uses the developer of this embodiment as a developer. In addition, an image carrier, a charging unit, a toner removing unit, and the like may be provided.

  FIG. 3 is a schematic configuration diagram showing a preferred example of a process cartridge containing the developer according to the present embodiment. The process cartridge 200 includes a photosensitive member 107 (latent image holding member), a charging roller 108, a developing device 111 including a developer holding member 111A, a photosensitive member cleaning device 113 (toner removing unit), and an opening 118 for exposure. , And the opening 117 for static elimination exposure is combined and integrated using the mounting rail 116.

  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 medium.

  The process cartridge shown in FIG. 3 includes a charging roller 108, a developing device 111, a cleaning device (cleaning means) 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. May be combined selectively. In the process cartridge of the present embodiment, if the developer holding member 111A is provided, the photosensitive member 107, the charging roller 108, the developing device 111, the cleaning device 113, the opening 118 for exposure, and the discharge exposure. You may provide at least 1 sort (s) selected from the group comprised from the opening part 117. FIG.

<Toner cartridge>
The toner cartridge according to this embodiment is detached from an image forming apparatus having at least a developing unit, and stores a developer containing toner to be supplied to the toner image forming unit. The toner is in the form. It should be noted that at least the toner may be stored in the toner cartridge of the present embodiment, and 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 freely attached and detached, the storability is maintained even in the toner cartridge in which the container is miniaturized by using the toner cartridge containing the toner of the present embodiment. Can be fixed at low temperature while maintaining high image quality.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited only to the Example shown below.
In the examples, “parts” and “%” mean “parts by mass” and “% by mass” unless otherwise specified.

<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.
(Molecular weight of resin)
The molecular weight distribution of the resin was performed under the following conditions. GPC uses “HLC-8120GPC, SC-8020 (manufactured by Tosoh Corporation)”, and the column uses two “TSKgel, SuperHM-H (6.0 mm ID × 15 cm, manufactured by Tosoh Corporation)” THF (tetrahydrofuran) was used as an eluent. As experimental conditions, an experiment was performed using a sample concentration of 0.5%, a flow rate of 0.6 ml / min, a sample injection amount of 10 μl, a measurement temperature of 40 ° C., and an IR detector. The calibration curve is “polystylen standard sample TSK standard” manufactured by Tosoh Corporation: “A-500”, “F-1”, “F-10”, “F-80”, “F-380”, “A-2500”. ”,“ F-4 ”,“ F-40 ”,“ F-128 ”, and“ F-700 ”.

(Volume average particle diameter of resin particles, colorant particles, etc.)
Volume average particle diameters of resin particles (resin particles), colorant particles, and the like were measured with a laser diffraction particle size measuring instrument (SALD2000A, manufactured by Shimadzu Corporation).

(Melting point of resin, glass transition temperature)
The melting point of the toner, the crystalline polyester resin, and the glass transition temperature of the toner and the amorphous resin were determined from each maximum peak measured in accordance with ASTM D3418-8. The glass transition point was the temperature at the intersection of the extension line of the base line and the rising line in the endothermic part, and the melting point was the temperature at the apex of the endothermic peak.
For the measurement, a differential scanning calorimeter (DSC-60A with automatic cooler, manufactured by Shimadzu Corporation) was used.

<Preparation of developer>
The developer was produced by first producing a toner and a carrier, and using them. In producing the toner, first, a resin particle dispersion, a colorant dispersion, and a release agent dispersion were produced, and toner particles were produced using them. Next, it was used to produce a toner and a developer.

-Preparation of non-crystalline polyester resin (A1) and non-crystalline resin particle dispersion (a1)-
In a heat-dried two-necked flask, 15 mol parts of polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane and polyoxypropylene (2,2) -2,2-bis (4 -Hydroxyphenyl) propane 85 mol part, terephthalic acid 10 mol part, fumaric acid 67 mol part, n-dodecenyl succinic acid 3 mol part, trimellitic acid 20 mol part, and these acid components (terephthalic acid, n After adding 0.05 mol part of dibutyltin oxide to the total number of moles of dodecenyl succinic acid, trimellitic acid and fumaric acid), introducing nitrogen gas into the container and maintaining the inert atmosphere to raise the temperature The copolycondensation reaction is carried out at 150 ° C. to 230 ° C. for 12 to 20 hours, and then gradually reduced in pressure at 210 ° C. to 250 ° C. to combine the amorphous polyester resin (A1). It was. This resin had a weight average molecular weight Mw of 65000 and a glass transition temperature Tg of 65 ° C.

  3000 parts of the obtained non-crystalline polyester resin, 10000 parts of ion-exchanged water, and 90 parts of surfactant sodium dodecylbenzenesulfonate were charged into an emulsification tank of a high-temperature and high-pressure emulsifier (Cabitron CD1010, slit: 0.4 mm). Then, after heating and melting at 130 ° C., it was dispersed at 110 ° C. at a flow rate of 3 L / m at 10,000 rpm for 30 minutes, passed through a cooling tank, and then a non-crystalline resin particle dispersion (high temperature / high pressure emulsifier (Cabitron CD1010 slit 0 .4 mm) was recovered to obtain an amorphous resin particle dispersion (a1).

-Preparation of crystalline polyester resin (B1) and crystalline resin particle dispersion (b1)-
Into a heat-dried three-necked flask, 45 mol parts of 1,9-nonanediol, 55 mol parts of dodecanedicarboxylic acid and 0.05 mol parts of dibutyltin oxide as a catalyst were added, and the air in the container was then decompressed. Was placed in an inert atmosphere with nitrogen gas, and stirred at 180 ° C. for 2 hours with mechanical stirring. Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 5 hours. When it became a viscous state, it was air-cooled, the reaction was stopped, and a crystalline polyester resin (B1) was synthesized. This resin had a weight average molecular weight Mw of 25000 and a melting point Tm of 73 ° C.
Thereafter, a crystalline resin particle dispersion (b1) was obtained using a high-temperature, high-pressure emulsification apparatus (Cabitron CD1010, slit: 0.4 mm) under the same conditions as in the preparation of the amorphous resin dispersion (A1).

-Preparation of colorant particle dispersion (1)-
-Cyan pigment (manufactured by Dainichi Seika Co., Ltd., Pigment Blue 15: 3 (copper phthalocyanine)): 1000 parts-Anionic surfactant (sodium lauryl sulfate, manufactured by Wako Pure Chemical Industries): 150 parts-Ion-exchanged water: 4000 parts

  A colorant particle dispersion obtained by mixing and dissolving the above and dispersing the colorant (cyan pigment) particles by dispersing for 1 hour using a high-pressure impact disperser Ultimateizer (manufactured by Sugino Machine Co., Ltd., HJP30006). Was prepared. The volume average particle size of the colorant (cyan pigment) particles in the colorant particle dispersion was 0.15 μm, and the colorant particle concentration was 20%. Further, sodium polyoxyethylene lauryl ether acetate (Bulite LCA manufactured by Sanyo Kasei Co., Ltd.) is added as an active ingredient with stirring and mixing so as to be 250 parts with respect to the pigment, heated at 40 ° C. and held for 1 hour. A colorant particle dispersion (1) was obtained.

-Preparation of Colorant Particle Dispersion (2)-
The colorant particle dispersion (2) was prepared in the same manner as the colorant particle dispersion (1) except that sodium polyoxyethylene tridecyl ether acetate (Burelite ECA) was used instead of sodium polyoxyethylene lauryl ether acetate. Obtained.

-Preparation of Colorant Particle Dispersion (3)-
A colorant particle dispersion (3) was obtained in the same manner as the colorant particle dispersion (1) except that sodium polyoxyethylene alkylsulfate (Emal 20CM) was used instead of sodium lauryl sulfate.

-Preparation of Colorant Particle Dispersion (4)-
A colorant particle dispersion (4) was obtained in the same manner as the colorant particle dispersion (1) except that sodium lauryl sulfate was not used.

-Preparation of Colorant Particle Dispersion (5)-
A colorant particle dispersion (5) was obtained in the same manner as the colorant particle dispersion (1) except that sodium polyoxyethylene lauryl ether acetate was not used.

-Preparation of colorant particle dispersion (6)-
A colorant particle dispersion liquid (6) was obtained in the same manner as the colorant particle dispersion liquid (1) except that Neogen RK (manufactured by Daiichi Kogyo Co., Ltd.) was used instead of sodium lauryl sulfate (Emar 0).

-Preparation of colorant particle dispersion (7)-
A colorant particle dispersion (7) was obtained in the same manner as the colorant particle dispersion (1) except that sulfated triolein (sulfated oil / sulfated fatty acid ester) was used instead of sodium lauryl sulfate.

-Preparation of Colorant Particle Dispersion (8)-
The same procedure as in the colorant particle dispersion (1) except that sodium dodecane-1,12-diol acetate ether (Sanyo Kasei Burelite SHAA, hydroxy ether carboxylic acid) was used instead of sodium polyoxyethylene lauryl ether acetate. A colorant particle dispersion (8) was obtained.

-Preparation of Colorant Particle Dispersion (9)-
The same procedure as in the colorant particle dispersion (4) except that sodium dodecane-1,12-diol ether ether (Sanyo Kasei Burelite SHAA, hydroxy ether carboxylic acid) was used instead of polyoxyethylene lauryl ether sodium acetate. A colorant particle dispersion (9) was obtained.

-Preparation of Colorant Particle Dispersion (10)-
Colorant particles in the same manner as the colorant particle dispersion (4) except that sodium alkylnaphthalenesulfonate (Kao Perex NBL, non-biodegradable dispersant) was used instead of sodium polyoxyethylene lauryl acetate A dispersion (10) was obtained.

-Preparation of release agent particle dispersion (1)-
・ Fatty acid amide wax (Nippon Seikatsu, Neutron D: 100 parts) ・ Anionic surfactant (manufactured by NOF Corporation, Newlex R): 2 parts ・ Ion-exchanged water: 300 parts After being dispersed using a homogenizer (manufactured by IKA, Ultra Tarrax T50), the dispersion is performed by a pressure discharge type gorin homogenizer (Gorin) to disperse release agent particles having a volume average particle size of 200 nm. A release agent particle dispersion (1) (release agent concentration: 20% by mass) was prepared.

[Production of toner]
-Production of Toner A1-
(Production of toner particles)
Amorphous resin particle dispersion (a1): 320 parts Crystalline resin particle dispersion (b1): 80 parts Colorant particle dispersion (1): 50 parts Release agent particle dispersion (1): 60 parts Aluminum sulfate (manufactured by Wako Pure Chemical Industries): 5 parts Surfactant aqueous solution: 10 parts 0.3M nitric acid aqueous solution: 50 parts Ion exchange water: 500 parts

  The above components were placed in a round stainless steel flask and dispersed using a homogenizer (manufactured by IKA, Ultra Turrax T50), and then heated to 45 ° C. with stirring in an oil bath for heating. After maintaining at 48 ° C., when it was confirmed that aggregated particles having an average particle size of about 5.2 μm were formed, after adding 100 parts of additional amorphous resin particle dispersion (a1), Hold for another 30 minutes.

  Subsequently, a 1N aqueous sodium hydroxide solution was gently added until pH 7.0 was reached, and then the mixture was heated to a predetermined temperature while continuing stirring and held for a predetermined time. Thereafter, the reaction product was filtered, washed with ion exchange water, and then dried using a vacuum dryer to obtain toner particles.

(External additive treatment)
Thereafter, 1.0 part of calcium carbonate (Takehara Chemical Industry Co., Ltd. (SL1500), New Mohs hardness: 3.0), alumina (Sumitomo Chemical Co., Ltd., AKP30), and 100 parts of the obtained toner particles as external additives. New Mohs hardness: 12.0) 0.5 part was mixed with a Henschel mixer and externally added to obtain toner A1.

-Production of Toner A2-
A toner A2 was obtained in the same manner as in the preparation of the toner A1, except that the colorant particle dispersion (1) was changed to the colorant particle dispersion (2) in the production of the toner A1.

-Production of Toner A3-
A toner A3 was obtained in the same manner as in the preparation of the toner A1, except that the colorant particle dispersion (1) was changed to the colorant particle dispersion (3) in the production of the toner A1.

-Production of Toner A4-
A toner A4 was obtained in the same manner as in the preparation of the toner A1, except that the colorant particle dispersion (1) was changed to the colorant particle dispersion (4) in the production of the toner A1.

-Production of Toner A5-
A toner A5 was obtained in the same manner as in the preparation of the toner A1, except that the colorant particle dispersion (1) was changed to the colorant particle dispersion (5) in the production of the toner A1.

-Production of Toner A6-
A toner A6 was obtained in the same manner as in the preparation of the toner A1, except that the colorant particle dispersion (1) was changed to the colorant particle dispersion (6) in the production of the toner A1. The content of neogen RK contained in the toner A6 was 5% by mass.

-Production of Toner A7-
A toner A7 was obtained in the same manner as in the preparation of the toner A1, except that the colorant particle dispersion (1) was changed to the colorant particle dispersion (7) in the production of the toner A1.

-Production of Toner A8-
A toner A8 was obtained in the same manner as in the preparation of the toner A1, except that the colorant particle dispersion (1) was changed to the colorant particle dispersion (8) in the production of the toner A1.

-Production of Toner A9-
A toner A9 was obtained in the same manner as in the preparation of the toner A4 except that the colorant particle dispersion (4) was changed to the colorant particle dispersion (9) in the production of the toner A4.

-Production of Toner A10-
A toner A10 was obtained in the same manner as in the preparation of the toner A4, except that the colorant particle dispersion (4) was changed to the colorant particle dispersion (10) in the production of the toner A4. The content of Perex NBL contained in the toner A10 was 3.8% by mass.

  Table 1 shows the types and contents of biodegradable dispersants contained in toner A1 to toner A10.

[Preparation of carrier]
100 parts of ferrite particles (Powder Tech, average particle size: 50 μm) and 2.5 parts of methyl methacrylate resin (Mitsubishi Rayon, weight average molecular weight: 95000) are placed in a pressure kneader together with 500 parts of toluene, and After stirring and mixing at 25 ° C. for 15 minutes, the temperature was raised to 70 ° C. while mixing under reduced pressure. After toluene was distilled off, the mixture was cooled and classified using a sieve having an opening of 105 μm. Coated carrier).

[Developer preparation]
The ferrite carrier and each of the toners A1 to A10 were mixed to prepare two-component developers (Developer 1 to Developer 10) having a toner concentration of 7% by mass.

<Production of photoconductor>
(Preparation of photoreceptor 1)
The cylindrical Al substrate was polished by a centerless polishing apparatus, and the 10-point average surface roughness Rz was 0.6 μm. As a cleaning process, the cylinder was degreased, etched with a 2% by mass sodium hydroxide solution for 1 minute, neutralized, and further washed with pure water. Next, as an anodizing treatment step, an anodized film (current density 1.0 A / dm ² ) was formed on the cylinder surface with a 10 mass% sulfuric acid solution. After washing with water, sealing was performed by dipping in a 1% by mass nickel acetate solution at 80 ° C. for 20 minutes. Furthermore, pure water washing | cleaning and the drying process were performed. In this manner, a 7 μm anodic oxide film was formed on the surface of the aluminum cylinder.

  One part of titanyl phthalocyanine having a strong diffraction peak at a Bragg angle (2θ ± 0.2 °) of X-ray diffraction spectrum on this aluminum substrate of 27.2 ° is polyvinyl butyral (ESREC BM-S, Sekisui Chemical). After mixing with 1 part and 100 parts of n-butyl acetate and treating with glass beads for 1 hour with a paint shaker to disperse, the resulting coating solution was dip coated on the undercoat layer at 100 ° C. for 10 minutes. A heat generation layer having a thickness of 0.15 μm was formed by heating and drying.

  Next, 2 parts of a benzidine compound (the following compound 1) having the following structure and 2.5 parts of a polymer compound (the following compound 2, viscosity average molecular weight: 39,000, n represents the number of repetitions) are 20 parts of chlorobenzene. The coating solution dissolved in was applied on the charge generation layer by a dip coating method, and heated at 110 ° C. for 40 minutes to form a charge transport layer having a thickness of 20 μm.

  Furthermore, 5 parts of the following compound 4, 7 parts of resol type phenol resin (PL-4852, manufactured by Gunei Chemical Co., Ltd.), 0.03 part of methylphenylpolysiloxane, and 20 parts of isopropanol are mixed and dissolved, and a protective layer is obtained. A forming coating solution was obtained. This coating solution was applied onto the charge transport layer of the image carrier by dip coating, and dried at 130 ° C. for 40 minutes to form a protective layer (outermost surface layer) having a thickness of 3 μm, thereby obtaining a photoreceptor.

(Preparation of photoconductor 2)
100 parts of zinc oxide (manufactured by Teika Co., Ltd., SMZ-017N) and 500 parts of toluene were mixed with stirring, 2 parts of a silane coupling agent (Nihon Unicar Co., Ltd., A1100) was added and stirred for 5 hours. Thereafter, toluene was distilled off under reduced pressure and baked at 120 ° C. for 2 hours to obtain surface-treated zinc oxide.

  35 parts of this surface-treated zinc oxide, 15 parts of a curing agent blocked isocyanate (Sumitomo Bayern Urethane Co., Ltd., Sumidur 3175) and 6 parts of butyral resin (Sekisui Chemical Co., Ltd., BM-1) 44 parts of Tomethylethylketone are mixed, Dispersion was obtained by dispersing for 2 hours in a sand mill using glass beads of 1 mmφ. As a catalyst, 0.005 part of dioctyltin dilaurate and 17 parts of a silicone resin (GE Toshiba Silicone, Tospearl 130) were added to the resulting dispersion to obtain a coating solution for an undercoat layer.

  This coating solution was applied onto an 84 mm drawn tube base material made of JIS A3003 alloy by a wet coating method, and dried and cured at 160 ° C. for 100 minutes to obtain an undercoat layer having a thickness of 20 μm.

  Chlorogallium phthalocyanine having strong diffraction peaks on the undercoat layer at X-ray diffraction spectra of Bragg angles (2θ ± 0.2 °) of 7.4 °, 16.6 °, 25.5 ° and 28.3 ° 1 part is mixed with 1 part of polybutyral resin (manufactured by Sekisui Chemical Co., Ltd., BM-S) and 100 parts of butyl acetate, dispersed with a glass bead for 1 hour in a paint shaker, and the resulting coating solution is placed on the undercoat layer. The film was dipped and dried by heating at 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.15 μm.

  Next, a coating solution for charge transport in which 3 parts of a polymer compound (compound 2) and 2 parts of a benzidine compound (compound 1) are dissolved in 20 parts of tetrahydrofuran is dipped on the charge generation layer, A charge transport layer was obtained, and an electrophotographic photoreceptor 2 was obtained.

(Preparation of photoreceptor 3)
JP-A-2006-330278 [0238] Compound 3 and Compound 4 are each 2 parts and 0.05 parts of tetramethoxysilane, 5 parts of isopropyl alcohol, 3 parts of tetrahydrofuran, and 0.3 part of distilled water. This was dissolved, 0.05 parts of ion exchange resin (Amberlyst 15E) was added thereto, and the mixture was stirred at room temperature (25 ° C.) for hydrolysis for 24 hours.

The ion exchange resin was filtered and separated from the obtained liquid, and 0.04 part of aluminum trisacetylacetonate and 0.02 part of 3,5-di-tert-butyl-4-hydroxytoluene were used with respect to 2 parts of the obtained filtrate. The liquid obtained by adding parts was designated as surface protective layer-forming coating solution A. This surface protective layer-forming coating solution A is applied on the charge transport layer of the image carrier before forming the protective layer on the photoreceptor 1 by a dipping coating method, and dried at room temperature (25 ° C.) for 30 minutes. Then, it was cured by heat treatment at 150 ° C. for 1 hour. In this way, a surface protective layer having a thickness of 3 μm was formed, and this was used as a photoreceptor 3.
It was confirmed by the above method whether or not the protective layer in the photoreceptor 1 to the photoreceptor 3 contains a resin having a three-dimensional crosslinked structure, and the results are shown in Table 2.

<Examples 1 to 12, Comparative Example 1>
(Evaluation)
Fuji Xerox printer DocuCenter Color 400CP remodeling machine (process speed 350 mm / s, mounted with photoconductor shown in Table 2, charging means, latent image forming means, toner image forming means, transfer means, fixing means, cleaning means, residual toner The image forming test (image coverage density is 5%) in a high-temperature and high-humidity (28 ° C., 85% RH) environment using a developer containing toner shown in Table 2. Then, an image forming test for 100,000 sheets was performed in an environment of low temperature and low humidity (10 ° C., 15% RH). The deformation toner rate of the residual toner collected after the image formation test of a total of 200000 sheets, the image quality of the formed image, the surface state of the photoreceptor, and the change of the cleaning blade were evaluated according to the following criteria.

-Deformed toner ratio of collected residual toner-
The deformed toner ratio of the collected residual toner was obtained as follows. Specifically, the toner collected by the toner collecting means is observed with 100 or more toners at a magnification of 3500 using a SEM (scanning electron microscope S800 manufactured by Hitachi, Ltd.). The collected images were taken into an image analyzer (Luxex 3 manufactured by Nireco Corporation) via the interface, the major axis and minor axis were calculated, and the ratio (number%) of those whose major axis / minor axis was less than 0.5 was defined as the deformation rate. When the deformation rate is 51% by number or more, the deformation is remarkable, and there is a high possibility of causing problems in actual use such as image defects, filming on the surface of the photoreceptor, and lack of a cleaning blade due to further use. The results are shown in Table 2.

-Image quality evaluation-
The image quality of the formed image was visually evaluated. The results are shown in Table 2.

-Surface condition of photoconductor-
The surface state of the photoreceptor was observed with a 50 × magnifier. The evaluation criteria are as follows, and the results are shown in Table 2.
A: Adhesion and filming are not observed even with loupe observation.
○: Although there is thin adhesion in the circumferential direction with a loupe, it does not appear in the image.
○-: Scratches and deposits are observed, but there is no significant influence on the image.
Δ: There are small scratches on the surface, uneven image density, and a slight problem in actual use.
X: Image defects and scratches are problems in actual use.

-Change of cleaning blade-
Changes in the cleaning blade were observed with a 100 × laser microscope. The evaluation criteria are as follows, and the results are shown in Table 2.
A: Both the image and non-image areas are good without wear.
○: There is a difference between the image portion and the non-image portion, but there is no problem in actual use.
○-: Slight level at which wear is observed in the image area but there is no influence on the image, or there is a density-decreasing part, but it is recovered immediately by turning from the developing machine.
Δ: Large wear in the image area, which may cause a problem depending on the image density.
X: A defective cleaning occurs, causing a problem on the image.

  From Table 2, Example 1 to Example 12 have a smaller toner deformation rate after the image formation test than Comparative Example 1, and the surface state of the photoconductor, the change of the cleaning blade, and the image quality of the formed image are It turns out that all are favorable.

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 another example of the image forming apparatus of this 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, 110 Photosensitive member (latent image holding member)
2Y, 2M, 2C, 2K, 108, 120 Charging roller 3Y, 3M, 3C, 3K, laser beam (electrostatic latent image forming means)
3, 110, 130 Exposure device (electrostatic latent image forming means)
4Y, 4M, 4C, 4K, 111, 140 Developing device (developing means)
5Y, 5M, 5C, 5K Primary transfer rollers 6Y, 6M, 6C, 6K, 113, 170 Photoconductor cleaning device (toner removing means)
8Y, 8M, 8C, 8K Toner cartridge 10Y, 10M, 10C, 10K Unit 26 Secondary transfer roller (transfer means)
28, 115 Fixing device (fixing means)
100 Image forming apparatus 112 Transfer apparatus 147 Developer cartridge (toner cartridge)
200 process cartridge,
300, P Recording medium (transfer object)

Claims (14)

  An electrostatic charge image developing toner comprising a binder resin, a colorant, and a biodegradable dispersant.   The electrostatic charge image developing toner according to claim 1, wherein the biodegradable dispersant contains an ether carboxylic acid compound.   The electrostatic charge image developing toner according to claim 2, wherein the ether carboxylic acid compound includes an alkyl ether carboxylic acid compound.   The electrostatic image developing toner according to claim 2, wherein the biodegradable dispersant contains a sulfate ester compound in addition to the ether carboxylic acid compound. A resin particle dispersion adjusting step of adjusting a resin particle dispersion in which resin particles are dispersed;
A colorant particle dispersion adjusting step for adjusting a colorant particle dispersion in which the colorant particles are dispersed;
A mixed solution adjusting step of mixing the resin particle dispersion and the colorant particle dispersion to adjust a mixed solution containing the resin particles and the colorant particles;
An aggregated particle adjusting step of adjusting aggregated particles in which the resin particles and the colorant particles are aggregated;
A fusion and coalescence step of fusing and coalescing the aggregated particle dispersion in which the aggregated particles are dispersed above the glass transition temperature of the resin particles,
At least one of the resin particle dispersion adjusting step, the colorant particle dispersion adjusting step, and the mixed solution adjusting step includes a step of adding a biodegradable dispersant. Toner manufacturing method.   The method for producing a toner for developing an electrostatic charge image according to claim 5, wherein the biodegradable dispersant contains an ether carboxylic acid compound.   The method for producing a toner for developing an electrostatic charge image according to claim 6, wherein the ether carboxylic acid compound includes an alkyl ether carboxylic acid compound.   The method for producing a toner for developing an electrostatic charge image according to claim 6, wherein the biodegradable dispersant contains a sulfate ester compound in addition to the ether carboxylic acid compound.   An electrostatic charge image developing developer comprising the electrostatic charge image developing toner according to any one of claims 1 to 4. Toner is stored in the image forming apparatus provided with the developing means, and is supplied to the developing means.
The toner is a toner cartridge which is the toner for developing an electrostatic charge image according to any one of claims 1 to 4.   A process cartridge comprising a developer holder and containing the developer for developing an electrostatic image according to claim 9. A latent image carrier,
An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the latent image holding member;
Developing means for developing the electrostatic latent image with a developer containing toner to form a toner image;
Transfer means for transferring the toner image formed on the latent image holding member to the surface of a recording medium;
Toner removing means for removing residual toner remaining on the surface of the latent image holding member,
The image forming apparatus according to claim 9, wherein the developer is an electrostatic charge image developing developer.   The image forming apparatus according to claim 12, further comprising a residual toner collecting and supplying unit that collects the residual toner removed by the toner removing unit and supplies the collected residual toner to the developing unit.   The image forming apparatus according to claim 12, wherein the layer constituting the outermost surface of the latent image holding member includes a resin having a three-dimensional cross-linking structure.

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