JP5522073B2 - Toner for electrostatic charge development, developer for electrostatic charge development, toner cartridge, process cartridge, image forming apparatus, and image forming method - Google Patents

Description

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

  For the purpose of forming an image having a brightness such as a metallic luster, glittering toner is used.

  At least a binder resin and a colorant are provided to provide a golden toner for developing an electrostatic latent image that is capable of obtaining a brilliant golden print with a small amount of a colorant and is excellent in chargeability and low-temperature fixability at low cost. Wherein the colorant is a glittering pigment obtained by coating silver on flat glass flakes having an average thickness of 2 μm to 5 μm and an average length in the longitudinal direction of 15 μm to 500 μm. A gold toner for developing an electrostatic latent image is disclosed (for example, see Patent Document 1).

JP 2003-207941 A

  An object of the present invention is to provide a toner for developing an electrostatic charge which is excellent in light resistance as compared with a case where no magenta pigment is contained as a colorant.

That is, the invention according to claim 1 is an aluminum pigment as a luster pigment and C.I. I. Pigment Yellow 74 and at least one selected from the group consisting of naphthol-based magenta pigments and quinacridone-based magenta pigments as magenta pigments as colorants ,
The ratio (mass basis) of the azo yellow pigment and the magenta pigment is 30: 1 to 80: 1,
The dispersion diameter of the glitter pigment is 3 μm or more and 7 μm or less,
The content of the glitter pigment is 10% by mass or more and 20% by mass or less,
The total amount of the azo-based yellow pigment and the magenta pigment is a least 10 parts by weight 20 parts by weight toner der Ru electrostatic charge development or less with respect to the bright pigment 100 parts by weight.

According to a second aspect of the present invention, there is provided an electrostatic charge developing developer comprising the electrostatic charge developing toner according to the first aspect.

The invention according to claim 3 contains the toner for electrostatic charge development according to claim 1 ,
The toner cartridge is detachable from the image forming apparatus.

The invention according to claim 4 contains the developer for developing electrostatic charge according to claim 2 , and develops the electrostatic charge image formed on the surface of the latent image holding member with the developer for developing electrostatic charge to form a toner image. Development means for forming
It is a process cartridge that can be attached to and detached from the image forming apparatus.

According to a fifth aspect of the present invention, there is provided a latent image holding member, a charging unit that charges the surface of the latent image holding member, an electrostatic charge image forming unit that forms an electrostatic charge image on the surface of the latent image holding member, and the electrostatic charge. A developing unit that develops the image with the electrostatic charge developing developer according to claim 2 to form a toner image, a transfer unit that transfers the toner image to a recording medium, and the toner image that is fixed to the recording medium. An image forming apparatus including a fixing unit.

The invention according to claim 6 is the charging process for charging the surface of the latent image holding member, the electrostatic charge image forming step for forming an electrostatic charge image on the surface of the latent image holding member, and the electrostatic charge image according to claim 2 . An image having a development step of developing with a developer for developing electrostatic charge to form a toner image, a transfer step of transferring the toner image to a recording medium, and a fixing step of fixing the toner image on the recording medium. It is a forming method.

  According to the first aspect of the present invention, there is provided an electrostatic charge developing toner which is excellent in light resistance as compared with a case where no magenta pigment is contained as a colorant.

According to the second aspect of the present invention, an electrostatic charge developing developer having excellent light resistance can be obtained as compared with the case where no magenta pigment is contained as a colorant.

According to the third aspect of the present invention, there is provided a toner cartridge that facilitates the supply of an electrostatic charge developing toner having excellent light resistance as compared with a case where no magenta pigment is contained as a colorant.

According to the fourth aspect of the present invention, the developer for developing an electrostatic charge having excellent light resistance can be easily handled as compared with the case where no magenta pigment is contained as a colorant, and it can be applied to image forming apparatuses having various configurations. Increases sex.

According to the fifth aspect of the present invention, there is provided an image forming apparatus using an electrostatic charge developing toner which is excellent in light resistance as compared with a case where no magenta pigment is contained as a colorant.

According to the sixth aspect of the present invention, there is provided an image forming method using an electrostatic charge developing toner which is excellent in light resistance as compared with a case where no magenta pigment is contained as a colorant.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment.

  Hereinafter, embodiments of an electrostatic charge developing toner, an electrostatic charge developing developer, a toner cartridge, a process cartridge, an image forming apparatus, and an image forming method of the present invention will be described in detail.

<Toner for electrostatic charge development>
The electrostatic charge developing toner according to the exemplary embodiment (hereinafter sometimes simply referred to as toner) contains a bright pigment, an azo yellow pigment, and a magenta pigment as colorants.
The toner of this embodiment is preferably used as a gold toner, but the color of the toner of this embodiment is not limited to gold.

In a toner using a combination of a bright pigment and an azo yellow pigment as a colorant, most of the reflected light generated by the bright pigment irradiates the azo yellow pigment, which has poor light resistance, and the azo yellow pigment fades. Therefore, there was a problem in light resistance as a toner. As a result, the target glitter may not be obtained under conditions of exposure to ultraviolet light for a long time.
In this embodiment, since the magenta pigment is used in combination with the azo yellow pigment, the reflected light irradiation of the bright pigment can be dispersed in the azo yellow pigment and the magenta pigment having excellent light resistance, and the light resistance as the toner is improved. The problem is improved.

  The toner of the present exemplary embodiment contains a bright pigment, an azo yellow pigment, and a magenta pigment as colorants, and may contain other components such as a binder resin and a release agent as necessary. Hereinafter, each component constituting the toner of the exemplary embodiment will be described.

-Colorant-
In the toner of the present exemplary embodiment, a bright pigment, an azo yellow pigment, and a magenta pigment are used as colorants. If necessary, other pigments may be used in combination.

(Bright pigment)
As the bright pigment used in the present embodiment, for example, metal powder such as aluminum, brass, bronze, nickel, stainless steel, zinc, mica coated with titanium oxide or yellow iron oxide, barium sulfate, layered silicate, Coated flaky inorganic crystal substrate such as layered aluminum silicate, single crystal plate-like titanium oxide, basic carbonate, bismuth oxyoxychloride, natural guanine, flaky glass powder, flaky glass powder metallized, etc. There is no particular limitation as long as it has glitter. Among these, it is desirable to use aluminum as a luster pigment for the reasons of luster, environmental safety, and chemical resistance.

(Azo yellow pigment)
Examples of the azo yellow pigment used in the present embodiment include C.I. I. Pigment Yellow 74, C.I. I. Pigment Yellow 1, 2, 3, 5, 6, 49, 65, 73, 75, 97, 98, 111, 116, 130, etc. monoazo pigments,
C. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, 95, 128, 166, disazo condensation pigments such as C.I. I. Pigment Yellow 12, 13, 14, 17, 55, 63, 81, 83, 87, 90, 106, 113, 114, 121, 124, 126, 127, 136, 152, 170, 171, 172, 174, 176, And a disazo pigment such as 188. Among these, C.I. I. It is desirable to use Pigment Yellow 74 as an azo yellow pigment.

(Magenta pigment)
Examples of the magenta pigment used in the present embodiment include naphthol-based magenta pigments, quinacridone-based magenta pigments, diketopyrrolopyrrole-based magenta pigments, and indigo-based magenta pigments. Among these, it is desirable to use at least one selected from the group consisting of naphthol-based magenta pigments and quinacridone-based magenta pigments as magenta pigments for charging and safety reasons.

(Other pigments)
In the present embodiment, other pigments other than the above pigments may be used in combination. Examples of other pigments that may be used in the present embodiment include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon, nonmagnetic ferrite, magnetite, red chrome yellow, molybdenum orange, permanent orange GTR, and pyrazolone orange. , Vulcan Orange, Benzidine Orange G, Induslen Brilliant Orange RK, Induslen Brilliant Oren GK, Bitumen, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Fast Sky Blue, Induslen Blue BC, Aniline Blue, Ultramarine Blue, Calco Oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxalate, manganese purple, fast violet B, methyl Violet Lake, chromium oxide, chromium green, pigment green, malachite green lake, final yellow green G, zinc oxide, titanium oxide, antimony white, and zinc sulfide.

  The ratio (mass basis) of the azo yellow pigment and the magenta pigment contained in the toner of this embodiment is desirably 5: 1 to 100: 1. If the ratio is less than 5: 1 magenta pigment, a good gold image can be obtained when a toner image is formed using the toner of this embodiment. If the ratio is more magenta than 100: 1, the light resistance of the toner image is further improved. The ratio is more preferably 20: 1 to 90: 1, and particularly preferably 30: 1 to 80: 1.

The dispersion diameter of the glitter pigment contained in the toner of this embodiment is desirably 1 μm or more and 10 μm or less. When the dispersion diameter of the glitter pigment is within the above range, a toner image having excellent gloss can be obtained. A more desirable range of the dispersion diameter is 2 μm or more and 9 μm, and 3 μm or more and 7 μm or less is particularly desirable.
The dispersion diameter of the glitter pigment is measured by the following method.
A 30 minute curing type epoxy resin is dropped on a stub dedicated to the apparatus and left for 30 minutes. The sample is coated on an epoxy resin, left for more than one day and night, and then a toner cross section is prepared with an ultramicrotome (ultrasonic). The cross section of the toner is observed with a scanning transmission electron microscope (STEM) or a Schottky field emission scanning electron microscope (Schottky FE-SEM) to determine the dispersion diameter of the pigment.

  The content of the glitter pigment in the toner of the exemplary embodiment is desirably 10% by mass or more and 20% by mass or less. When the content of the glitter pigment is within the above range, a toner image having excellent gloss can be obtained. A more desirable range of the content is 11% by mass or more and 18% by mass or less, and particularly preferably 13% by mass or more and 17% by mass or less.

  The total amount of the azo yellow pigment and the magenta pigment contained in the toner of this embodiment is desirably 5 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the glitter pigment contained in the toner of this embodiment. When the total amount of the azo yellow pigment and the magenta pigment is within the above range, an image exhibiting a good gold color can be obtained when a toner image is formed using the toner of this embodiment. The total amount of the azo yellow pigment and the magenta pigment is more preferably 7 parts by mass or more and 25 parts by mass or less, and particularly preferably 10 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the glitter pigment.

-Binder resin-
The toner of this embodiment may contain a binder resin.
Examples of the binder resin used in the present embodiment include ethylene resins such as polyester, polyethylene, and polypropylene; styrene resins such as polystyrene and α-polymethylstyrene; and (meth) acrylic resins such as polymethyl methacrylate and polyacrylonitrile. Resin; Polyamide resin, polycarbonate resin, polyether resin and copolymer resins thereof may be used. Among these, it is desirable to use a polyester resin that forms an image with high smoothness of the surface of the fixed image and further excellent glitter.
In the following, polyester resins that are particularly preferably used will be described.

The polyester resin according to this embodiment is obtained, for example, mainly by condensation polymerization of polyvalent carboxylic acids and polyhydric alcohols.
Examples of the polyvalent carboxylic acid include terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid, and other aromatic carboxylic acids; maleic anhydride, fumaric acid, succinic acid, Examples thereof include aliphatic carboxylic acids such as alkenyl succinic anhydride and adipic acid; alicyclic carboxylic acids such as cyclohexanedicarboxylic acid, and one or more of these polycarboxylic acids are used.
Among these polycarboxylic acids, aromatic carboxylic acids are preferably used, and trivalent or higher carboxylic acids (trimellitic acid) together with dicarboxylic acids to form a crosslinked structure or a branched structure in order to ensure good fixing properties. And acid anhydrides thereof) are preferably used in combination.

Examples of the polyhydric alcohol include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentylglycol, and glycerin; cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol And alicyclic diols such as A; aromatic diols such as ethylene oxide adduct of bisphenol A and propylene oxide adduct of bisphenol A. One or more of these polyhydric alcohols are used.
Among these polyhydric alcohols, aromatic diols and alicyclic diols are preferable, and among these, aromatic diols are more preferable. In order to secure better fixability, a trihydric or higher polyhydric alcohol (glycerin, trimethylolpropane, pentaerythritol) may be used in combination with the diol in order to form a crosslinked structure or a branched structure.

The toner according to the exemplary embodiment may contain a crystalline polyester resin as a binder resin from the viewpoint of more rapid changes in viscosity due to heating, and from the viewpoint of achieving both mechanical strength and low-temperature fixability.
The content of the crystalline polyester resin in the toner according to the exemplary embodiment is preferably 2% by mass or more and 30% by mass or less, and more preferably 4% by mass or more and 25% by mass or less.

  The melting temperature of the crystalline polyester resin is preferably in the range of 50 ° C. to 100 ° C., preferably in the range of 55 ° C. to 95 ° C., and more preferably in the range of 60 ° C. to 90 ° C. preferable.

  Note that the “crystalline polyester resin” according to the present embodiment is not a stepwise endothermic change in differential scanning calorimetry (hereinafter sometimes abbreviated as “DSC”). It has an endothermic peak. The crystalline polyester resin is a polymer obtained by copolymerizing other components with respect to the main chain. When the other components are 50% by mass or less, the copolymer is also called crystalline polyester.

  The crystalline polyester resin is synthesized from an acid (dicarboxylic acid) component and an alcohol (diol) component. In the following, the “acid-derived constituent component” refers to a polyester resin before the synthesis of the polyester resin. Refers to a component that was an acid component, and “alcohol-derived component” refers to a component that was an alcohol component before the synthesis of the polyester resin.

[Acid-derived components]
Examples of the acid for forming the acid-derived constituent component include various dicarboxylic acids, but the acid-derived constituent component in the crystalline polyester resin according to this embodiment is preferably a linear aliphatic dicarboxylic 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, An acid anhydride may be mentioned, but not limited thereto. Among these, adipic acid, sebacic acid, and 1,10-decanedicarboxylic acid are preferable.

As the acid-derived constituent component, other constituent components such as a dicarboxylic acid-derived constituent component having a double bond and a dicarboxylic acid-derived constituent component having a sulfonic acid group may be contained.
Examples of the dicarboxylic acid having a sulfone group include, but are not limited to, 2-sulfoterephthalic acid sodium salt, 5-sulfoisophthalic acid sodium salt, and sulfosuccinic acid sodium salt. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned. Among these, 5-sulfoisophthalic acid sodium salt and the like are preferable.
Content of acid-derived components other than these aliphatic dicarboxylic acid-derived components (dicarboxylic acid-derived components having double bonds and / or dicarboxylic acid-derived components having sulfonic acid groups) in the acid-derived components Is preferably 1 component mol% or more and 20 component mol% or less, more preferably 2 component mol% or more and 10 component mol% or less.

  In the present specification, “constituent mol%” means that the acid-derived constituent component in the entire acid-derived constituent component in the polyester resin or the alcohol constituent component in the entire alcohol-derived constituent component is 1 unit (mol). ) Indicates the percentage.

[Alcohol-derived components]
As the alcohol to be an alcohol-derived constituent component, an aliphatic diol is desirable, for example, 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-dodecanediol, 1,12-undecanediol, 1,13-tridecanediol 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol, and the like, but are not limited thereto. Among these, ethylene glycol, 1,4-butanediol, and 1,6-hexanediol are preferable.

(Production method of polyester resin)
There is no restriction | limiting in particular as a manufacturing method of a polyester resin, It manufactures with the general polyester polymerization method which makes an acid component and an alcohol component react. For example, direct polycondensation, transesterification, and the like are used depending on the type of monomer. The molar ratio (acid component / alcohol component) at the time of reacting the acid component with the alcohol component varies depending on the reaction conditions and the like, and thus cannot be generally described. However, in order to increase the molecular weight, it is usually 1/1. The degree is preferred.

  Catalysts that can be used in the production of the polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; metals such as zinc, manganese, antimony, titanium, tin, zirconium, and germanium Compound; phosphorous acid compound; phosphoric acid compound; and amine compound.

  The molecular weight (weight average molecular weight; Mw) of the binder resin is preferably from 15,000 to 300,000, and more preferably from 25,000 to 130,000.

  In the present embodiment, the weight average molecular weight of the binder resin is a value calculated by measuring by GPC (Gel Permeation Chromatography). Specifically, Tosoh Co., Ltd. HLC-8120 was used for GPC, Tosoh TSKgel SuperHM-M (15 cm) was used for the column, and the binder resin was measured with a THF solvent. Next, the weight average molecular weight of the binder resin was calculated using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

-Release agent-
The toner of this embodiment may contain a release agent.
Examples of the release agent include paraffin wax such as low molecular weight polypropylene and low molecular weight polyethylene; silicone resin; rosins; rice wax; carnauba wax; The melting temperature of these release agents is preferably 50 ° C. or higher and 100 ° C. or lower, and more preferably 60 ° C. or higher and 95 ° C. or lower.
The content of the release agent in the toner is desirably 0.5% by mass or more and 15% by mass or less, and more desirably 1.0% by mass or more and 12% by mass or less.

-Other additives-
In addition to the components described above, various components such as an internal additive, a charge control agent, inorganic powder (inorganic particles), and organic particles may be added to the toner of the exemplary embodiment as necessary.

  Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments.

  As the inorganic particles, for example, known inorganic particles such as silica particles, titanium oxide particles, alumina particles, cerium oxide particles, or those obtained by hydrophobizing the surface thereof may be used alone or in combination of two or more kinds. Good. Among these, silica particles having a refractive index smaller than that of the binder resin are preferably used. Further, the silica particles may be subjected to various surface treatments, and for example, those subjected to surface treatment with a silane coupling agent, a titanium coupling agent, a silicone oil or the like are preferably used.

-Toner characteristics-
The volume average particle diameter of the toner in the exemplary embodiment is preferably in the range of 2 μm to 20 μm, more preferably in the range of 3 μm to 15 μm, and still more preferably in the range of 5 μm to 10 μm. When the volume average particle diameter is 2 μm or more, the toner fluidity is improved and the chargeability of each particle is easily improved. Further, since the charge distribution does not widen, fogging on the background and toner spillage from the developing device are less likely to occur. Moreover, if it is 2 micrometers or more, cleaning property will not become difficult. If the volume average particle diameter is 20 μm or less, the resolution is improved, so that a sufficient image quality is obtained and the recent demand for high image quality is satisfied.

  The volume average particle size is measured using a Coulter Multisizer (manufactured by Coulter Inc.) with an aperture diameter of 50 μm. At this time, the measurement was performed after the toner was dispersed in an electrolyte aqueous solution (Isoton aqueous solution) and dispersed by ultrasonic waves for 30 seconds or more.

Furthermore, it is preferable that the toner of the present exemplary embodiment has a spherical shape with a shape factor SF1 in the range of 110 to 140. When the shape is spherical in this range, transfer efficiency and image density are improved, and a high-quality image is formed.
The shape factor SF1 is more preferably in the range of 110 to 130.

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

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

<Toner production method>
The toner of this embodiment may be prepared by adding an external additive to the toner particles after the toner particles are manufactured.
The method for producing the toner particles is not particularly limited, and the toner particles are produced by a known dry method such as a kneading / pulverizing method or a wet method such as an emulsion aggregation method or a suspension polymerization method.
The kneading and pulverization method involves mixing materials such as a colorant, then melt-kneading the above materials using a kneader, an extruder, etc., and roughly pulverizing the resulting melt-kneaded product, followed by a jet mill In this method, the toner particles having a desired particle diameter are obtained using an air classifier.
Among these methods, the emulsion aggregation method is preferable because the shape of the toner particles and the particle diameter of the toner particles can be easily controlled, and the control range of the toner particle structure such as the core-shell structure is wide. Hereinafter, a method for producing toner particles by the emulsion aggregation method will be described in detail.

  In the emulsification aggregation method of the present embodiment, the raw material constituting the toner particles is emulsified to form resin particles (emulsion particles), the aggregation step of forming aggregates of the resin particles, and the aggregates are fused. Fusion process.

(Emulsification process)
The resin particle dispersion can be prepared by a general polymerization method, such as emulsion polymerization, suspension polymerization, dispersion polymerization, or the like. In addition, a solution in which an aqueous medium and a binder resin are mixed is used. Alternatively, emulsification may be performed by applying a shearing force 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 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. By evaporating the solvent, a resin particle dispersion is produced.

Examples of the aqueous medium include water such as distilled water and ion-exchanged water; alcohols; and the like.
Examples of the dispersant used in the emulsification step include water-soluble polymers such as polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, and sodium polymethacrylate; sodium dodecylbenzenesulfonate, Anionic surfactants such as sodium octadecyl sulfate, sodium oleate, sodium laurate, potassium stearate, cationic surfactants such as laurylamine acetate, stearylamine acetate, lauryltrimethylammonium chloride, amphoteric such as lauryldimethylamine oxide Ionic surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene Surfactants such as nonionic surfactants such as alkyl amines; and the like are; tricalcium phosphate, aluminum hydroxide, calcium sulfate, calcium carbonate, inorganic salts such as barium carbonate.

  Examples of the disperser used for preparing the emulsion include a homogenizer, a homomixer, a pressure kneader, an extruder, and a media disperser. As the size of the resin particles, the average particle diameter (volume average particle diameter) is desirably 1.0 μm or less, more desirably 60 nm or more and 300 nm or less, and further desirably 150 nm or more and 250 nm or less. . When the thickness is 60 nm or more, the resin particles tend to be unstable particles in the dispersion, and thus the resin particles may be easily aggregated. If the particle size is 1.0 μm or less, the particle size distribution of the toner may become narrow.

  In preparing the release agent dispersion, the release agent is dispersed in water together with an ionic surfactant, a polymer electrolyte such as a polymer acid or a polymer base, and then heated to a temperature equal to or higher than the melting temperature of the release agent. Dispersion treatment is performed using a homogenizer or a pressure discharge type disperser to which a strong shearing force is applied while heating. By undergoing such treatment, a release agent dispersion is obtained. During the dispersion treatment, an inorganic compound such as polyaluminum chloride may be added to the dispersion. Examples of desirable inorganic compounds include polyaluminum chloride, aluminum sulfate, highly basic polyaluminum chloride (BAC), polyaluminum hydroxide, and aluminum chloride. Among these, polyaluminum chloride and aluminum sulfate are desirable. The release agent dispersion is used in the emulsion aggregation method, but the release agent dispersion may also be used when the toner is produced by suspension polymerization.

By the dispersion treatment, a release agent dispersion liquid containing release agent particles having a volume average particle diameter of 1 μm or less is obtained. In addition, the more preferable volume average particle diameter of the release agent particles is 100 nm or more and 500 nm or less.
When the volume average particle diameter is 100 nm or more, the properties of the binder resin to be used are affected, but in general, the release agent component is easily taken into the toner. In the case of 500 nm or less, the state of dispersion of the release agent in the toner is good.

  For the preparation of the colorant (azo yellow pigment and magenta pigment) dispersion, a known dispersion method can be used. For example, a general dispersion means such as a rotary shear type homogenizer, a ball mill having a medium, a sand mill, a dyno mill, or an optimizer. Can be adopted and is not limited at all. The colorant is dispersed in water together with a polymer electrolyte such as an ionic surfactant, a polymer acid, or a polymer base. The volume average particle diameter of the dispersed colorant particles may be 1 μm or less, but if it is in the range of 80 nm or more and 500 nm or less, the dispersion of the colorant in the toner is preferable without impairing the cohesiveness.

  The colorant (brilliant pigment) dispersion may be prepared in the same manner as in the case of the azo yellow pigment and the magenta pigment, or the bright pigment and the binder resin are dispersed and dissolved in a solvent and mixed. Alternatively, a dispersion of a glitter pigment coated with a resin may be prepared by dispersing in water by phase inversion emulsification or shear emulsification.

(Aggregation process)
In the agglomeration step, a resin particle dispersion, a colorant dispersion, a release agent dispersion, etc. are mixed to form a mixed liquid, which is heated to agglomerate at a temperature lower than the glass transition temperature of the resin particles to form aggregated particles. To do. Aggregated particles are often formed by making the pH of the mixed solution acidic under stirring. The pH is preferably in the range of 2 to 7, and in this case, it is also effective to use a flocculant.
In the aggregation step, the release agent dispersion may be added and mixed at once with various dispersions such as a resin particle dispersion, or may be added in multiple portions.

  As the aggregating agent, a surfactant having a polarity opposite to that of the surfactant used for the dispersant, an inorganic metal salt, and a divalent or higher-valent metal complex are preferably used. In particular, the use of a metal complex is particularly desirable because the amount of the surfactant used can be reduced and the charging characteristics are improved.

As the inorganic metal salt, an aluminum salt and a polymer thereof are particularly suitable. In order to obtain a narrower particle size distribution, the valence of the inorganic metal salt is bivalent than monovalent, trivalent than bivalent, trivalent than trivalent, and tetravalent than trivalent. Inorganic metal salt polymers are more suitable.
In this embodiment, it is desirable to use a polymer of a tetravalent inorganic metal salt containing aluminum in order to obtain a narrow particle size distribution.

  Further, a toner having a structure in which the surface of the core aggregated particles is coated with a resin may be prepared by additionally adding a resin particle dispersion when the aggregated particles have a desired particle size (coating step). In this case, the release agent and the colorant are not easily exposed on the toner surface, which is desirable from the viewpoint of chargeability and developability. In the case of additional addition, a flocculant may be added or pH adjustment may be performed before additional addition.

(Fusion process)
In the fusion step, the agglomeration is stopped by raising the pH of the suspension of aggregated particles to a range of 3 to 9 under stirring conditions in accordance with the aggregation step, and the glass transition temperature of the resin is higher than the glass transition temperature. The aggregated particles are fused by heating at a temperature. Moreover, when it coat | covers with the said resin, this resin is also united and a core aggregated particle is coat | covered. The heating time may be performed to the extent that fusion is performed, and may be performed for about 0.5 hour to 10 hours.

Cool after fusion to obtain fused particles. Further, in the cooling step, crystallization may be promoted by reducing the cooling rate in the vicinity of the glass transition temperature (range of glass transition temperature ± 10 ° C.) of the resin, so-called slow cooling.
The fused particles obtained by fusing are made into toner particles through a solid-liquid separation process such as filtration and, if necessary, a washing process and a drying process.

To the obtained toner particles, inorganic oxides such as silica, titania and aluminum oxide may be added and adhered as external additives for the purpose of charge adjustment, fluidity provision, charge exchangeability and the like. These can be performed by, for example, a V-type blender, a Henschel mixer, a Redige mixer, or the like, and may be attached in stages. The addition amount of the external additive is preferably in the range of 0.1 part or more and 5 parts or less and more preferably in the range of 0.3 part or more and 2 parts or less with respect to 100 parts of the toner particles.
Further, if necessary, coarse particles of toner may be removed after external addition using an ultrasonic sieving machine, a vibration sieving machine, a wind sieving machine, or the like.

  In addition to the external additives described above, other components (particles) such as a charge control agent, organic particles, a lubricant, and an abrasive may be added.

  Although there is no restriction | limiting in particular as a charge control agent, A colorless or light-colored thing is used preferably. For example, quaternary ammonium salt compounds, nigrosine compounds, complexes of aluminum, iron, chromium, and triphenylmethane pigments can be used.

Examples of the organic particles include particles usually used as an external additive on the toner surface, such as vinyl resins, polyester resins, and silicone resins. These inorganic particles and organic particles are used as fluidity aids, cleaning aids, and the like.
Examples of the lubricant include fatty acid amides such as ethylene bis stearic acid amide and oleic acid amide, and fatty acid metal salts such as zinc stearate and calcium stearate.
As an abrasive | polishing agent, the above-mentioned silica, alumina, cerium oxide etc. are mentioned, for example.

  When toner particles are formed by the emulsion aggregation method, the glitter pigment, azo yellow pigment, and magenta pigment, which are part of the toner constituent material, are highly dispersed by the action of the surfactant and are dispersed until they are fixed on the paper. Sex is thought to be maintained. Thus, if the dispersibility of each pigment is maintained, it is considered that the bright pigment and the magenta pigment serve as a shield and partly prevent direct irradiation of the azo yellow pigment with ultraviolet light. In addition, it is considered that part of the reflected light from the glittering pigment is prevented by the same mechanism.

<Developer for electrostatic charge development>
The developer for electrostatic charge development of the present embodiment (hereinafter sometimes simply referred to as developer) includes at least the toner of the present embodiment.
The toner of this embodiment is used as it is as a one-component developer or as a two-component developer. When used as a two-component developer, it is used by mixing with a carrier.

  The carrier that can be used in the two-component developer is not particularly limited, and a known carrier is used. Examples thereof include magnetic metals such as iron oxide, nickel and cobalt, magnetic oxides such as ferrite and magnetite, resin-coated carriers having a resin coating layer on the surface of the core material, and magnetic dispersion carriers. Further, a resin-dispersed carrier in which a conductive material or the like is dispersed in a matrix resin may be used.

  Coating resins and matrix resins used for carriers include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic. Examples include, but are not limited to, an acid copolymer, a straight silicone resin containing an organosiloxane bond or a modified product thereof, a fluororesin, a polyester, a polycarbonate, a phenol resin, and an epoxy resin.

  Examples of the conductive material include metals such as gold, silver and copper, carbon black, titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate, tin oxide, and carbon black, but are not limited thereto. It is not something.

  Examples of the core material of the carrier include magnetic metals such as iron, nickel, and cobalt, magnetic oxides such as ferrite and magnetite, and glass beads. However, in order to use the carrier for the magnetic brush method, it is a magnetic material. It is desirable. The volume average particle diameter of the carrier core material is generally in the range of 10 to 500 μm, and preferably in the range of 30 to 100 μm.

  In order to coat the surface of the core material of the carrier with a resin, there may be mentioned a method of coating with a coating layer forming solution prepared by dissolving the coating resin and, if necessary, various additives in an appropriate solvent. The solvent is not particularly limited, and may be selected in consideration of the coating resin to be used, coating suitability, and the like.

  Specific resin coating methods include an immersion method in which the carrier core material is immersed in the coating layer forming solution, a spray method in which the coating layer forming solution is sprayed onto the surface of the carrier core material, and the carrier core material is fluidized air. A fluidized bed method in which the coating layer forming solution is sprayed in a state of being suspended by the above, a kneader coater method in which the carrier core material and the coating layer forming solution are mixed in a kneader coater, and the solvent is removed.

  In the two-component developer, the mixing ratio (mass ratio) of the toner of the present embodiment and the carrier is preferably in the range of toner: carrier = 1: 100 to 30: 100, and about 3: 100 to 20: 100. The range of is more desirable.

<Toner cartridge, process cartridge, image forming apparatus and image forming method>
The image forming apparatus of the present embodiment includes a latent image holding member, a charging unit that charges the surface of the latent image holding member, an electrostatic charge image forming unit that forms an electrostatic charge image on the surface of the latent image holding member, and the electrostatic image forming unit. Developing means for developing a charge image with the developer of the present embodiment to form a toner image, transfer means for transferring the toner image to a recording medium, and fixing means for fixing the toner image to the recording medium. It is to be prepared.

  The image forming apparatus according to the present exemplary embodiment includes, for example, an image forming apparatus that sequentially repeats primary transfer of each toner image held on a latent image holding body to an intermediate transfer body, and a plurality of latent images including developing units for each color. It may be a tandem type image forming apparatus in which the holding body is arranged in series on the intermediate transfer body.

  In the image forming apparatus of the present embodiment, for example, a cartridge structure (process cartridge) in which a portion including the developing unit that stores the developer of the present embodiment is detachable from the image forming apparatus may be used. A cartridge structure (toner cartridge) in which the toner storage portion of the present embodiment is removably attached to the image forming apparatus as the replenishment toner supplied to the developing unit.

  According to the image forming apparatus of the present embodiment, a charging step of charging the surface of the latent image holding member, an electrostatic charge image forming step of forming an electrostatic charge image on the surface of the latent image holding member, and the electrostatic charge image of the present embodiment. Image forming according to this embodiment, which includes a developing step of developing with a developer to form a toner image, a transfer step of transferring the toner image to a recording medium, and a fixing step of fixing the toner image to the recording medium. The method is performed.

The image forming apparatus according to the present embodiment will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to the present exemplary embodiment. The image forming apparatus according to the present embodiment has a tandem configuration in which a plurality of photosensitive members as latent image holding members, that is, a plurality of image forming units (image forming means) are provided.

As shown in FIG. 1, the image forming apparatus according to the present embodiment includes four image forming units 50Y, 50M, 50C, and 50K that respectively form yellow, magenta, cyan, and black toner images, and a glittering gold color. Image forming units 50G for forming toner images are arranged in parallel (tandem) at intervals. The image forming units are arranged in the order of the image forming units 50Y, 50M, 50C, 50K, and 50G from the upstream side in the rotation direction of the intermediate transfer belt 33.
Here, each of the image forming units 50Y, 50M, 50C, 50K, and 50G has the same configuration except for the color of the toner in the stored developer. The unit 50Y will be described as a representative. It should be noted that reference numerals with magenta (M), cyan (C), black (K), and gold color (G) are attached to the same parts as the image forming unit 50Y instead of yellow (Y). Description of the image forming units 50M, 50C, 50K, and 50G is omitted.

  The yellow image forming unit 50Y includes a photoconductor 11Y as a latent image holding member, and this photoconductor 11Y is rotationally driven at a predetermined process speed by a driving unit (not shown) along the direction of an arrow A shown in the drawing. It has come to be. As the photoreceptor 11Y, for example, an organic photoreceptor having sensitivity in the infrared region is used.

  A charging roll (charging means) 18Y is provided above the photoconductor 11Y. A predetermined voltage is applied to the charging roll 18Y by a power source (not shown), and the surface of the photoconductor 11Y is predetermined. Charged to a certain potential.

  Around the photoreceptor 11Y, an exposure device (electrostatic charge image forming means) 19Y for exposing the surface of the photoreceptor 11Y to form an electrostatic charge image is disposed downstream of the charging roll 18Y in the rotation direction of the photoreceptor 11Y. Has been. Here, as the exposure device 19Y, an LED array that can be miniaturized is used in terms of space, but the present invention is not limited to this, and an electrostatic charge image forming unit using another laser beam or the like is used. Of course there is no problem.

  Further, a developing device (developing unit) 20Y including a developer holding body that holds a yellow developer is disposed around the photoconductor 11Y on the downstream side in the rotation direction of the photoconductor 11Y with respect to the exposure device 19Y. The electrostatic charge image formed on the surface of the photoreceptor 11Y is visualized with yellow toner, and a toner image is formed on the surface of the photoreceptor 11Y.

  Below the photoconductor 11Y, an intermediate transfer belt (primary transfer means) 33 for primary transfer of a toner image formed on the surface of the photoconductor 11Y extends below the five photoconductors 11Y, 11M, 11C, 11K, and 11G. Are arranged as follows. The intermediate transfer belt 33 is pressed against the surface of the photoreceptor 11Y by the primary transfer roll 17Y. Further, the intermediate transfer belt 33 is stretched by three rolls of a drive roll 12, a support roll 13, and a bias roll 14, and is rotated in the direction of arrow B at a moving speed equal to the process speed of the photoconductor 11Y. It has become. A yellow toner image is primarily transferred onto the surface of the intermediate transfer belt 33, and toner images of each color of magenta, cyan, black, and gold (gold) are sequentially primary transferred and stacked.

  Further, around the photoreceptor 11Y, the toner remaining on the surface of the photoreceptor 11Y and the retransferred toner are cleaned downstream of the primary transfer roll 17Y in the rotation direction (arrow A direction) of the photoreceptor 11Y. A cleaning device 15Y is arranged. The cleaning blade in the cleaning device 15Y is attached so as to be in pressure contact with the surface of the photoreceptor 11Y in the counter direction.

  A secondary transfer roll (secondary transfer unit) 34 is pressed against the bias roll 14 that stretches the intermediate transfer belt 33 via the intermediate transfer belt 33. The toner image primarily transferred and laminated on the surface of the intermediate transfer belt 33 is recorded on the surface of the recording paper (recording medium) P fed from a paper cassette (not shown) at the pressure contact portion between the bias roll 14 and the secondary transfer roll 34. Electrostatically transferred. At this time, since the toner image transferred and laminated on the intermediate transfer belt 33 is the gold toner image on the top (uppermost layer), the toner image transferred on the surface of the recording paper P has a gold toner image. It becomes the lowest (lowermost layer).

  Also, downstream of the secondary transfer roll 34, a fixing device (fixing means) for fixing the toner image transferred on the recording paper P onto the surface of the recording paper P by heat and pressure to form a permanent image. 35 is arranged.

  As the fixing device 35, for example, a low-surface energy material typified by a fluororesin component or a silicone resin is used on the surface, and a fixing belt having a belt shape is represented by a fluororesin component or a silicone resin on the surface. And a cylindrical fixing roll is used.

  Next, the operation of each of the image forming units 50Y, 50M, 50C, 50K, and 50G that forms an image of each color of yellow, magenta, cyan, black, and gold (gold) will be described. Since the operations of the image forming units 50Y, 50M, 50C, 50K, and 50G are the same, the operation of the yellow image forming unit 50Y will be described as a representative example.

  In the yellow developing unit 50Y, the photoreceptor 11Y rotates in the direction of arrow A at a predetermined process speed. The surface of the photoconductor 11Y is negatively charged to a predetermined potential by the charging roll 18Y. Thereafter, the surface of the photoreceptor 11Y is exposed by the exposure device 19Y, and an electrostatic charge image corresponding to the image information is formed. Subsequently, the negatively charged toner is reversely developed by the developing device 20Y, and the electrostatic charge image formed on the surface of the photoreceptor 11Y is visualized on the surface of the photoreceptor 11Y to form a toner image. Thereafter, the toner image on the surface of the photoreceptor 11Y is primarily transferred onto the surface of the intermediate transfer belt 33 by the primary transfer roll 17Y. After the primary transfer, transfer residual components such as toner remaining on the surface of the photoreceptor 11Y are scraped off and cleaned by the cleaning blade of the cleaning device 15Y to prepare for the next image forming process.

  The above operations are performed by the image forming units 50Y, 50M, 50C, 50K, and 50G, and the toner images visualized on the surfaces of the photoreceptors 11Y, 11M, 11C, 11K, and 11G are successively transferred to the intermediate transfer belt. 33 is transferred onto the surface. In the color mode, toner images of each color are transferred in the order of yellow, magenta, cyan, black, and gold (gold), but in the two-color and three-color modes, the necessary color toners are also in this order. Only the image is transferred alone or in multiple transfer. Thereafter, the toner image singly or multiply transferred onto the surface of the intermediate transfer belt 33 is secondarily transferred onto the surface of the recording paper P conveyed from a paper cassette (not shown) by the secondary transfer roll 34, and then the fixing device 35. It is fixed by heating and pressurizing. The toner remaining on the surface of the intermediate transfer belt 33 after the secondary transfer is cleaned by a belt cleaner 16 constituted by a cleaning blade for the intermediate transfer belt 33.

  The yellow image forming unit 50Y includes a developing device 20Y including a developer holding body for holding a yellow developer, a photoconductor 11Y, a charging roll 18Y, and a cleaning device 15Y, which are integrated from the main body of the image forming apparatus. It is configured as a detachable process cartridge. The image forming units 50G, 50K, 50C, and 50M are also configured as process cartridges in the same manner as the image forming unit 50Y.

  The toner cartridges 40Y, 40M, 40C, 40K, and 40G are cartridges that store toner of each color and are attached to and detached from the image forming apparatus, and are connected to a developing device corresponding to each color by a toner supply pipe (not shown). ing. When the toner stored in each toner cartridge becomes low, the toner cartridge is replaced.

Hereinafter, although an Example and a comparative example are given and this embodiment is described in detail in detail, this embodiment is not limited to the following examples. In the following description, “part” represents “part by mass” and “%” represents “% by mass” unless otherwise specified. Moreover, Examples other than Example 1- Example 5, Example 26, Example 36, Example 37, Example 43, and Example 44 are outside the scope of the present invention.

(Synthesis of binder resin)
Dimethyl adipate: 74 parts Dimethyl terephthalate: 192 parts Bisphenol A ethylene oxide adduct: 216 parts Ethylene glycol: 38 parts Tetrabutoxy titanate (catalyst): 0.037 parts
The above components are placed in a heat-dried two-necked flask, and nitrogen gas is introduced into the container and heated while stirring in an inert atmosphere, and then subjected to a copolycondensation reaction at 160 ° C. for 7 hours, and then gradually up to 10 Torr. The temperature was raised to 220 ° C. while reducing the pressure to 4 hours. Once the pressure was returned to normal pressure, 9 parts of trimellitic anhydride was added, the pressure was gradually reduced to 10 Torr, and maintained at 220 ° C. for 1 hour to synthesize a binder resin.

(Preparation of binder resin dispersion)
・ Binder resin: 160 parts ・ Ethyl acetate: 233 parts ・ Sodium hydroxide aqueous solution (0.3N): 0.1 part The above ingredients were placed in a 1000 ml separable flask and heated at 70 ° C. A resin mixed solution was prepared by stirring with Science Co., Ltd. While further stirring this resin mixture, 373 parts of ion-exchanged water was gradually added, phase inversion emulsification was carried out, and the solvent was removed to obtain a binder resin dispersion (solid content concentration: 30%).

(Preparation of glitter pigment dispersion 1)
Aluminum pigment (Showa Aluminum Powder Co., Ltd., 2173EA 6 μm): 100 parts Anionic surfactant (Daiichi Kogyo Seiyaku, Neogen R): 1.5 parts Ion-exchanged water: 400 parts Aluminum pigment paste The solvent was removed, and the pigment was mechanically pulverized and classified to 5.2 μm using a star mill (LMZ, manufactured by Ashizawa Finetech Co., Ltd.). Then, it mixes with the said activator and ion-exchange water, It disperse | distributes about 1 hour using an emulsification disperser Cavitron (the Taiheiyo Kiko Co., Ltd. product, CR1010), and disperse | distributes luster pigment particle (aluminum pigment). Brilliant pigment dispersion 1 was prepared (solid content concentration: 20%). The pigment dispersion diameter was 5.2 μm.

(Preparation of glitter pigment dispersion 2)
The glitter pigment dispersion 2 was prepared in the same manner as the glitter pigment dispersion 1 except that the pigment grinding by the star mill of the glitter pigment dispersion 1 was performed to 3.2 μm. The pigment dispersion diameter was 3.2 μm.

(Preparation of glitter pigment dispersion 3)
Dispersion of the bright pigment in the same manner as the bright pigment dispersion 1 except that the aluminum pigment of the bright pigment dispersion 1 was changed to an aluminum pigment (2172EA 7 μm, manufactured by Showa Aluminum Powder Co., Ltd.) and was not pulverized. Liquid 3 was prepared. The pigment dispersion diameter was 6.9 μm.

(Preparation of glitter pigment dispersion 4)
The glitter pigment dispersion 4 was prepared in the same manner as the glitter pigment dispersion 1 except that the pigment grinding by the star mill of the glitter pigment dispersion 1 was performed to 2.8 μm. The pigment dispersion diameter was 2.8 μm.

(Preparation of glitter pigment dispersion 5)
The glittering pigment dispersion 1 was changed to the aluminum pigment (Showa Aluminum Powder Co., Ltd., 210EA 9 μm) and pulverized to 7.2 μm in the same manner as the glittering pigment dispersion 1 Pigment dispersion 5 was prepared. The pigment dispersion diameter was 7.2 μm.

(Preparation of glitter pigment dispersion 6)
The glitter pigment dispersion 6 was prepared in the same manner as the glitter pigment dispersion 1 except that the pigment grinding by the star mill of the glitter pigment dispersion 1 was performed to 1.3 μm. The pigment dispersion diameter was 1.3 μm.

(Preparation of glitter pigment dispersion 7)
The glitter pigment dispersion liquid 7 was prepared in the same manner as the glitter pigment dispersion liquid 1 except that the pigment grinding by the star mill of the glitter pigment dispersion liquid 1 was performed to 0.7 μm. The pigment dispersion diameter was 0.7 μm.

(Preparation of glitter pigment dispersion 8)
The glittering pigment dispersion 1 was changed to the aluminum pigment (Showa Aluminum Powder Co., Ltd., 260EA, 10 μm), and brilliant in the same manner as the glittering pigment dispersion 1 except that it was not pulverized with a star mill. Pigment dispersion 8 was prepared. The pigment dispersion diameter was 9.9 μm.

(Preparation of glitter pigment dispersion 9)
The glittering pigment dispersion 1 was changed to an aluminum pigment (Showa Aluminum Powder Co., Ltd., 220EA 17 μm) and pulverized to 10.2 μm in the same way as the glittering pigment dispersion 1 Pigment dispersion 9 was prepared. The pigment dispersion diameter was 10.2 μm.

(Preparation of glitter pigment dispersion 10)
Bright pigment dispersion 1 except that aluminum pigment of bright pigment dispersion 1 was changed to titanium oxide-coated mica (Merck, Iriodin ^(R) 120 Luster Satin 10.6 μm) and pulverization was performed to 5.2 μm. A glittering pigment dispersion 10 was prepared in the same manner as described above. The pigment dispersion diameter was 5.2 μm.

(Preparation of azo-based yellow pigment dispersion 1)
・ C. I. Pigment Yellow 74 (manufactured by Dainichi Seika): 50 parts, ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku): 5 parts, ion-exchanged water: 192.9 parts The above ingredients are mixed, and an optimizer (manufactured by Sugino Machine Co., Ltd.). ) For 10 minutes at 240 MPa to obtain an azo yellow pigment dispersion (solid content concentration: 20%).

(Preparation of azo yellow pigment dispersion 2)
C. I. An azo yellow pigment dispersion 2 was prepared in the same manner as the preparation of the azo yellow pigment dispersion 1 except that Pigment Yellow 93 (manufactured by Dainichi Seika) was used (solid content concentration: 20%).

(Preparation of magenta pigment dispersion 1)
The pigment is C.I. which is a naphthol-based magenta pigment. I. Except for changing to Pigment Red 238 (manufactured by Sanyo Dye), magenta pigment dispersion 1 was obtained in the same manner as in the preparation of azo-based yellow pigment dispersion 1 (solid content concentration: 20%).

(Preparation of magenta pigment dispersion 2)
The pigment is C.I. which is a quinacridone magenta pigment. I. Pigment Red 122: Magenta pigment dispersion 2 was obtained in the same manner as in the preparation of azo yellow pigment dispersion 1 except that it was changed to (manufactured by Dainichi Seika) (solid content concentration: 20%).

(Preparation of magenta pigment dispersion 3)
The pigment is an azo magenta pigment, C.I. I. Pigment Red 5: A magenta pigment dispersion 3 was obtained in the same manner as the preparation of the azo yellow pigment dispersion 1 except that the pigment was changed to (manufactured by Dainichi Seika Kogyo Co., Ltd.) (solid content concentration: 20%).

(Preparation of release agent dispersion)
Carnauba wax (Toa Kasei Co., Ltd., RC-160): 50 parts Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 1.0 parts Ion-exchanged water: 200 parts The above was mixed and heated to 95 ° C. and dispersed using a homogenizer (Ultra Turrax T50, manufactured by IKA), then dispersed for 360 minutes with a Manton Gorin high-pressure homogenizer (Gorin), and the volume average particle A release agent dispersion (solid content concentration: 20%) prepared by dispersing release agent particles having a diameter of 0.23 μm was prepared.

[Example 1]
<Preparation of Toner 1>
Binder resin dispersion: 480 parts Release agent dispersion: 72 parts Bright pigment dispersion 1: 140 parts Azo-based yellow pigment dispersion 1: 20.6 parts Magenta pigment dispersion (magenta pigment dispersion Liquid 1): 0.37 parts Nonionic surfactant (IGEPAL CA897): 1.40 parts The above raw materials are put into a 2 L cylindrical stainless steel container and sheared at 4000 rpm with a homogenizer (IKA, Ultra Lalux T50). For 10 minutes while mixing. Next, 1.75 parts of a 10% nitric acid aqueous solution of polyaluminum chloride as a flocculant was gradually added dropwise, and the homogenizer was rotated at 5000 rpm for 15 minutes and mixed to obtain a raw material dispersion.
Thereafter, the raw material dispersion was transferred to a polymerization vessel equipped with a stirring device using two paddle stirring blades for forming a laminar flow, and a thermometer, and started to be heated with a mantle heater at a stirring speed of 810 rpm. The growth of aggregated particles was promoted at 54 ° C. At this time, the pH of the raw material dispersion was controlled in the range of 2.2 to 3.5 with 0.3N nitric acid or 1N sodium hydroxide aqueous solution. The agglomerated particles were formed by maintaining the above pH range for about 2 hours.
Next, 100 parts of a binder resin dispersion was added, and the resin particles of the binder resin were adhered to the surface of the aggregated particles. The temperature was further raised to 56 ° C., and aggregated particles were prepared while confirming the particle diameter with an optical microscope and Multisizer II. Thereafter, the pH was raised to 8.0 in order to fuse the aggregated particles, and then the temperature was raised to 67.5 ° C. After confirming that the aggregated particles were fused with an optical microscope, the pH was lowered to 6.0 while maintaining the temperature at 67.5 ° C., and the heating was stopped after 1 hour, followed by cooling at a rate of temperature decrease of 1.0 ° C./min. Thereafter, the mixture was sieved with a 20 μm mesh, washed repeatedly with water, and then dried with a vacuum dryer to obtain toner particles. The obtained toner particles had a volume average particle diameter of 12.2 μm.
To 100 parts of the obtained toner particles, 1.5 parts of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., RY50) was mixed and blended at 10,000 rpm for 30 seconds using a sample mill. Thereafter, the toner was prepared by sieving with a vibrating sieve having an opening of 45 μm.

<Creation of career>
・ Toluene 14 parts ・ Styrene-methyl methacrylate copolymer (component ratio: 80/20, weight average molecular weight: 70,000) 2 parts ・ MZ500 (zinc oxide, titanium industry) 0.6 parts The solution for forming a coating layer in which zinc oxide was dispersed by stirring was prepared. Next, this coating solution and 100 parts of ferrite particles (volume average particle size: 38 μm) are put in a vacuum degassing kneader and stirred at 60 ° C. for 30 minutes, and then degassed by further reducing pressure while heating. The carrier was made by drying.

<Create developer>
The obtained carrier and toner 1 were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to prepare developer 1.

<Evaluation>
The developer used as a sample is filled in a developer unit of DocuCentre-III C7600 manufactured by Fuji Xerox Co., Ltd. shown in FIG. 1, and fixed on a recording paper (OK topcoat + paper, manufactured by Oji Paper Co., Ltd.). A solid image having a toner loading of 4.5 g / cm ² was formed at a temperature of 190 ° C. and a fixing pressure of 4.0 kg / cm ² .

-Glossiness evaluation-
The gloss of the fixed image was evaluated by Micro-TRI-Gloss (TRICOR Systems Co., Ltd.) according to the 75-degree specular gloss measurement method described in JIS Z8721-1997. The evaluation criteria are as follows.
1: Gloss value> 90%
2: 60% <gloss value ≦ 90%
3: Gloss value ≦ 60%

-Light resistance evaluation-
Ultraviolet irradiation was performed under the condition that an Xe lamp was attached to a Ci weatherometer manufactured by Atlas, and CIRA was used as an inner filter and soda lime was used as an outer filter. The irradiation amount was 300 kJ / m ² at an illuminance of 40 mW / m ^{2 in} terms of 400 nm. L1, a1, and b1 of the image before the light resistance test, and L2, a2, and b2 after the irradiation were measured using an Olympus microspectroscope OSP-SP200, respectively. ΔE was calculated by the following equation.
(ΔE = {(L1-L2) ² + (a1-a2) ² + (b1-b2) ² } ^1/2
1: ΔE <1 Light resistance sufficient 2: 1 ≦ ΔE <3 Light tolerance allowable range 3: 3 ≦ ΔE <4 Although there is a concern, allowable range 4: ΔE ≧ 4 Out of light resistance allowable range

―Evaluation of gold reproducibility―
Visually observed under illumination for color observation (natural daylight illumination) in accordance with JIS K 5600-4-3: 1999 “General test method for paints—Part 4: Visual characteristics of coating film—Section 3: Visual comparison of colors” The gold reproducibility was evaluated sensuously. The level of 3 or less is actually usable.
1: Vivid gold.
2: Normal gold color.
3: Gold with a slight orange color.
4: Red and yellowish gold.

[Examples 2 to 49, Comparative Example 1]
In Example 2, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 2, the azo yellow pigment dispersion 1 was changed to 26 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) was changed to 0.56 parts. Toner 2 and developer 2 were prepared and evaluated in the same manner as in Example 1.

  In Example 3, from the preparation of the toner 1 of Example 1, the glittering pigment dispersion 2, 15.1 parts of the azo-based yellow pigment dispersion 1, and 0.28 parts of the magenta pigment dispersion (magenta pigment dispersion 1). Toner 3 and developer 3 were prepared and evaluated in the same manner as in Example 1.

  In Example 4, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 3, 15.1 parts of the azo-based yellow pigment dispersion 1, and 0.28 parts of the magenta pigment dispersion (magenta pigment dispersion 1). Toner 4 and developer 4 were prepared and evaluated in the same manner as in Example 1.

  In Example 5, preparation of the toner 1 of Example 1 was changed from the glitter pigment dispersion 3, the azo yellow pigment dispersion 1 to 26 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) to 0.56 parts. Then, toner 5 and developer 5 were prepared and evaluated in the same manner as in Example 1.

  In Example 6, preparation of the toner 1 of Example 1 was changed from the glitter pigment dispersion 4, the azo yellow pigment dispersion 1 to 26 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) to 0.56 parts. Then, toner 6 and developer 6 were prepared and evaluated in the same manner as in Example 1.

  In Example 7, from the preparation of the toner 1 of Example 1, the glittering pigment dispersion 4, 15.1 parts of the azo-based yellow pigment dispersion 1, and 0.28 parts of the magenta pigment dispersion (magenta pigment dispersion 1). Toner 7 and developer 7 were prepared and evaluated in the same manner as in Example 1.

  In Example 8, from the preparation of the toner 1 of Example 1, the glittering pigment dispersion 2, the azo yellow pigment dispersion 1 12.3 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.28 parts. Toner 8 and developer 8 were prepared and evaluated in the same manner as in Example 1.

  In Example 9, from the production of the toner 1 of Example 1, the glitter pigment dispersion 3, 12.3 parts of the azo yellow pigment dispersion 1, and 0.28 parts of the magenta pigment dispersion (magenta pigment dispersion 1). Toner 9 and developer 9 were prepared and evaluated in the same manner as in Example 1.

  In Example 10, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 5, 15.1 parts of the azo yellow pigment dispersion 1, and 0.28 parts of the magenta pigment dispersion (magenta pigment dispersion 1). The toner 10 and the developer 10 were prepared and evaluated in the same manner as in Example 1.

  In Example 11, preparation of the toner 1 of Example 1 was changed from the glitter pigment dispersion 5, the azo yellow pigment dispersion 1 to 26 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) to 0.56 parts. Then, toner 11 and developer 11 were prepared and evaluated in the same manner as in Example 1.

  In Example 12, from the preparation of the toner 1 of Example 1, the glittering pigment dispersion 3, the azo yellow pigment dispersion 1 was 28.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) was 0.56 parts. The toner 12 and the developer 12 were prepared and the same evaluation as in Example 1 was performed.

  In Example 13, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 2, the azo yellow pigment dispersion 1 was 28.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) was 0.56 parts. The toner 13 and the developer 13 were prepared and evaluated in the same manner as in Example 1.

  In Example 14, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 6, 39.8 parts of the azo-based yellow pigment dispersion 1, and 0.84 parts of the magenta pigment dispersion (magenta pigment dispersion 1). Toner 14 and developer 14 were prepared and evaluated in the same manner as in Example 1.

  In Example 15, from the preparation of the toner 1 of Example 1, the bright pigment dispersion 6, the azo yellow pigment dispersion 1 8.2 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.19 parts. The toner 15 and the developer 15 were prepared and evaluated in the same manner as in Example 1.

  In Example 16, from the preparation of the toner 1 of Example 1, the bright pigment dispersion 8, the azo yellow pigment dispersion 1 8.2 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.19 parts. Toner 16 and developer 16 were prepared and evaluated in the same manner as in Example 1.

  In Example 17, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 8, the azo yellow pigment dispersion 1 39.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.84 parts. Toner 17 and developer 17 were prepared and evaluated in the same manner as in Example 1.

  In Example 18, from the production of the toner 1 of Example 1, 42.6 parts of the glitter pigment dispersion liquid 6, 42.6 parts of the azo yellow pigment dispersion liquid 1, and 0.84 part of magenta pigment dispersion liquid (magenta pigment dispersion liquid 1). The toner 18 and the developer 18 were prepared and evaluated in the same manner as in Example 1.

  In Example 19, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 7, the azo yellow pigment dispersion 1 39.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.84 parts. The toner 19 and the developer 19 were prepared and evaluated in the same manner as in Example 1.

  In Example 20, from the preparation of the toner 1 of Example 1, the bright pigment dispersion 7, the azo yellow pigment dispersion 1 8.2 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.19 parts. The toner 20 and the developer 20 were prepared and evaluated in the same manner as in Example 1.

  In Example 21, from the preparation of the toner 1 of Example 1, 5.5 parts of the glitter pigment dispersion 6, 5.5 parts of the azo yellow pigment dispersion 1, and 0.09 parts of the magenta pigment dispersion (magenta pigment dispersion 1). The toner 21 and the developer 21 were prepared and evaluated in the same manner as in Example 1.

  In Example 22, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 8, 5.5 parts of the azo yellow pigment dispersion 1, and 0.09 parts of the magenta pigment dispersion (magenta pigment dispersion 1). The toner 22 and the developer 22 were prepared and evaluated in the same manner as in Example 1.

  In Example 23, from the preparation of the toner 1 of Example 1, the bright pigment dispersion 9, the azo yellow pigment dispersion 1 8.2 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.19 parts. The toner 23 and the developer 23 were prepared and evaluated in the same manner as in Example 1.

  In Example 24, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 8, the azo yellow pigment dispersion 1 39.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.84 parts. The toner 24 and the developer 24 were prepared and evaluated in the same manner as in Example 1.

  In Example 25, from the production of the toner 1 of Example 1, the glitter pigment dispersion 8, the azo yellow pigment dispersion 1 42.6 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) 0.84 parts. The toner 25 and the developer 25 were prepared and evaluated in the same manner as in Example 1.

  In Example 26, the toner 26 and the developer 26 were prepared by changing the preparation of the toner 1 of Example 1 to the magenta pigment dispersion (magenta pigment dispersion 2), and the same evaluation as in Example 1 was performed.

  In Example 27, from the preparation of the toner 1 of Example 1, the bright pigment dispersion 6 and the azo yellow pigment dispersion 1 were 39.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 2) was 0.84 parts. The toner 27 and the developer 27 were produced as modified, and the same evaluation as in Example 1 was performed.

  In Example 28, from the preparation of the toner 1 of Example 1, 8.2 parts of the glitter pigment dispersion 6, 8.2 parts of the azo yellow pigment dispersion 1, and 0.19 parts of the magenta pigment dispersion (magenta pigment dispersion 2). The toner 28 and the developer 28 were prepared and evaluated in the same manner as in Example 1.

  In Example 29, from the preparation of the toner 1 of Example 1, the bright pigment dispersion 8, the azo yellow pigment dispersion 1 8.2 parts, and the magenta pigment dispersion (magenta pigment dispersion 2) 0.19 parts. The toner 29 and the developer 29 were prepared and evaluated in the same manner as in Example 1.

  In Example 30, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 8, the azo yellow pigment dispersion 1 39.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 2) 0.84 parts. The toner 30 and the developer 30 were prepared and evaluated in the same manner as in Example 1.

  In Example 31, the preparation of the toner 1 of Example 1 was changed to the magenta pigment dispersion (magenta pigment dispersion 3), and the toner 31 and the developer 31 were prepared and evaluated in the same manner as in Example 1.

  In Example 32, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 6, the azo yellow pigment dispersion 1 39.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 3) 0.84 parts. The toner 32 and the developer 32 were prepared and evaluated in the same manner as in Example 1.

  In Example 33, from the preparation of the toner 1 of Example 1, 8.2 parts of the glitter pigment dispersion 6, 8.2 parts of the azo yellow pigment dispersion 1, and 0.19 parts of the magenta pigment dispersion (magenta pigment dispersion 3). The toner 33 and the developer 33 were prepared and the same evaluation as in Example 1 was performed.

  In Example 34, from the preparation of the toner 1 of Example 1, the bright pigment dispersion 8, the azo yellow pigment dispersion 1 8.2 parts, and the magenta pigment dispersion (magenta pigment dispersion 3) 0.19 parts. The toner 34 and the developer 34 were prepared and evaluated in the same manner as in Example 1.

  In Example 35, from the preparation of the toner 1 of Example 1, the glitter pigment dispersion 8, the azo yellow pigment dispersion 1 39.8 parts, and the magenta pigment dispersion (magenta pigment dispersion 3) 0.84 parts. The toner 35 and the developer 35 were prepared, and the same evaluation as in Example 1 was performed.

  In Example 36, the toner 36 and the developer 36 were prepared by changing the binder resin dispersion from the preparation of the toner 1 of Example 1 to 700 parts and the release agent dispersion from 105 parts, and the same evaluation as in Example 1 was performed. Went.

  In Example 37, 350 parts of the binder resin dispersion, 52.5 parts of the release agent dispersion, and 0.44 parts of magenta pigment dispersion (magenta pigment dispersion 1) were prepared from the preparation of the toner 1 of Example 1. The toner 37 and the developer 37 were prepared and the same evaluation as in Example 1 was performed.

  In Example 38, from the preparation of the toner 1 of Example 1, the binder resin dispersion was changed to 1000 parts, the release agent dispersion was changed to 150 parts, and the magenta pigment dispersion (magenta pigment dispersion 1) was changed to 0.35 parts. The toner 38 and the developer 38 were produced and evaluated in the same manner as in Example 1.

  In Example 39, the toner 39 and the developer 39 were prepared by changing the binder resin dispersion from the preparation of the toner 1 of Example 1 to 280 parts and the release agent dispersion from 42 parts, and evaluated in the same manner as in Example 1. Went.

  In Example 40, toner 40 and development were performed by changing the preparation of the toner 1 of Example 1 to 16.8 parts of the azo-based yellow pigment dispersion liquid 1 and 4.20 parts of the magenta pigment dispersion liquid (magenta pigment dispersion liquid 1). An agent 40 was produced and evaluated in the same manner as in Example 1.

  In Example 41, toner 41 and development were carried out by changing the preparation of the toner 1 of Example 1 to 17.8 parts of the azo yellow pigment dispersion liquid 1 and 3.17 parts of the magenta pigment dispersion liquid (magenta pigment dispersion liquid 1). Agent 41 was prepared and evaluated in the same manner as in Example 1.

  In Example 42, the toner 42 and development were performed by changing the azo-based yellow pigment dispersion 1 to 20.3 parts and the magenta pigment dispersion (magenta pigment dispersion 1) to 0.75 parts from the preparation of the toner 1 of Example 1. The agent 42 was produced and evaluated in the same manner as in Example 1.

  In Example 43, toner 43 and development were performed by changing the azo-based yellow pigment dispersion 1 to 20.3 parts and the magenta pigment dispersion (magenta pigment dispersion 1) from 0.65 parts from the preparation of the toner 1 of Example 1. Agent 43 was prepared and evaluated in the same manner as in Example 1.

  In Example 44, toner 44 and development were performed by changing the azo-based yellow pigment dispersion 1 to 20.7 parts and the magenta pigment dispersion (magenta pigment dispersion 1) to 0.28 parts from the preparation of the toner 1 of Example 1. Agent 44 was prepared and evaluated in the same manner as in Example 1.

  In Example 45, toner 45 and development were performed by changing the azo-based yellow pigment dispersion 1 to 20.8 parts and the magenta pigment dispersion (magenta pigment dispersion 1) to 0.23 parts from the preparation of the toner 1 of Example 1. Agent 45 was prepared and evaluated in the same manner as in Example 1.

  In Example 46, the toner 46 and development were performed by changing the preparation of the toner 1 of Example 1 to 20.8 parts for the azo-based yellow pigment dispersion liquid 1 and 0.21 part for the magenta pigment dispersion liquid (magenta pigment dispersion liquid 1). The agent 46 was produced and evaluated in the same manner as in Example 1.

  In Example 47, toner 47 and development were performed by changing the azo-based yellow pigment dispersion 1 to 20.8 parts and the magenta pigment dispersion (magenta pigment dispersion 1) to 0.20 parts from the preparation of the toner 1 of Example 1. Agent 47 was prepared and evaluated in the same manner as in Example 1.

  In Example 48, the preparation of the toner 1 of Example 1 was changed to the azo-based yellow pigment dispersion 2 to prepare a toner 48 and a developer 48, and the same evaluation as in Example 1 was performed.

  In Example 49, the toner 49 and the developer 49 were prepared by changing the preparation of the toner 1 of Example 1 to the glittering pigment dispersion liquid 10 and evaluated in the same manner as in Example 1.

  In Comparative Example 1, toner 50 and developer were prepared by changing the azo-based yellow pigment dispersion 1 to 21.0 parts and the magenta pigment dispersion (magenta pigment dispersion 1) to 0 parts from the preparation of the toner 1 of Example 1. 50 were prepared and evaluated in the same manner as in Example 1.

The results of Examples 1 to 49 and Comparative Example 1 are shown in Table 1.
Further, the azo yellow pigment and the magenta pigment in the toner were confirmed by accurately weighing about 10 mg of the toner and dissolving it in toluene to prepare a 10 cc toluene solution. If the particle size of the glitter pigment is 1 μm or more, leave it for 12 hours or more, and if it is less than 1 μm, precipitate the glitter pigment with a centrifuge and distill off a part of the supernatant. The type of pigment was identified from the infrared absorption spectrum. More specifically, specific absorption wavelengths of the azo yellow pigment and the magenta pigment were measured in advance to identify the type of pigment in the residue.
The amount was determined from the Lambert-Beer law by measuring the ultraviolet absorption spectrum of the supernatant. More specifically, the concentration of the pigment was measured from the height of the wavelength by measuring the number of absorption systems from the relationship between the intensity and concentration of the absorption peak at a specific wavelength for each pigment, and then obtaining the ultraviolet absorption spectrum of the sample.
Needless to say, the amount of toluene is adjusted so that the relationship between the sensitivity of the measuring instrument and the pigment concentration matches.

  In Table 1, “amount of colored pigment relative to glitter pigment” means the total amount (mass basis) of azo yellow pigment and magenta pigment relative to 100 parts of glitter pigment.

DESCRIPTION OF SYMBOLS 11 Photoconductor 12 Drive roll 13 Support roll 14 Bias roll 15 Cleaning apparatus 16 Belt cleaner 17 Primary transfer roll 18 Charging roll 19 Exposure apparatus 20 Developing apparatus 34 Secondary transfer roll 35 Fixing device 40 Toner cartridge 50 Image forming unit

Claims (6)

Aluminum pigments as bright pigments and C.I. I. Pigment Yellow 74 and at least one selected from the group consisting of naphthol-based magenta pigments and quinacridone-based magenta pigments as magenta pigments as colorants ,
The ratio (mass basis) of the azo yellow pigment and the magenta pigment is 30: 1 to 80: 1,
The dispersion diameter of the glitter pigment is 3 μm or more and 7 μm or less,
The content of the glitter pigment is 10% by mass or more and 20% by mass or less,
The azo-based yellow pigment and the total amount of the magenta pigment is 20 parts by mass der Ru toner for developing an electrostatic image less than 10 parts by weight with respect to the bright pigment 100 parts by weight. An electrostatic charge developing developer comprising the electrostatic charge developing toner according to claim 1 . Containing the electrostatic charge developing toner according to claim 1 ;
A toner cartridge to be attached to and detached from the image forming apparatus. A developer for storing the electrostatic charge developing developer according to claim 2 and developing a static image formed on the surface of the latent image holding body with the electrostatic charge developing developer to form a toner image,
A process cartridge attached to and detached from the image forming apparatus. The latent image holding member, a charging unit that charges the surface of the latent image holding member, an electrostatic charge image forming unit that forms an electrostatic charge image on the surface of the latent image holding member, and the electrostatic charge image according to claim 2 . Image forming apparatus comprising: a developing unit that forms a toner image by developing with a developer for electrostatic charge development; a transfer unit that transfers the toner image to a recording medium; and a fixing unit that fixes the toner image on the recording medium. apparatus. 3. A charging step of charging the surface of the latent image holding member, an electrostatic charge image forming step of forming an electrostatic charge image on the surface of the latent image holding member, and the electrostatic charge image by the developer for electrostatic charge development according to claim 2. An image forming method comprising: a developing step of developing to form a toner image; a transferring step of transferring the toner image onto a recording medium; and a fixing step of fixing the toner image on the recording medium.