JP2007093809A - Electrostatic charge image developing toner and method for manufacturing electrostatic charge image developing toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner having wide fixing latitude and excellent thermal storage property and electrostatic chargeability. <P>SOLUTION: The electrostatic charge image developing toner has a core-and-shall structure provided with a shell on the surface of a core particle including a crystalline polyester resin, non-crystalline polyester resin and a colorant, in which the core particle includes a compound resin bonded with a styrene resin and a polyester resin and further, the shell includes a copolymerized resin of polystyrene and (meth)acryl. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrostatic charge image developing toner for visualizing an electrostatic charge image through respective steps of development, transfer, and fixing in an electrophotographic apparatus such as a copying machine, a printer, a facsimile, and the like, and the toner. It relates to the manufacturing method.

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

  In recent years, from the viewpoint of energy saving, which has been particularly demanding, a heat melting method is generally used in which toner is melted and fixed by heat, and the fixing process with high energy consumption is improved. Furthermore, by using low-temperature fixing, it is possible to shorten the start-up time after power input, extend the life of the fixing roll member, and increase the process speed. Therefore, it is desirable for the toner to lower the fixing temperature. As a toner for low-temperature fixing, a method using crystalline polyester that melts sharply at low temperature has been studied (for example, see Patent Document 1). However, when a low-melting crystalline resin is used to obtain low-temperature fixing, glass is used. Since the transition temperature also decreases, blocking due to the crystalline resin occurs, storage properties are unfavorable, and problems such as deterioration in chargeability occur, and it is difficult to achieve both fixability and storage stability. Further, in the toner, the release agent is easily exposed on the surface, and the storage stability is a problem.

  In addition, a method of coating crystalline polyester with an amorphous polyester resin is known (for example, see Patent Document 2). However, there is a problem that the coating layer is peeled off by impact stress in the developing unit or the like, and the coating layer is peeled off. As a result, the crystalline resin is exposed on the toner surface. A crystalline resin generally has a low resistance and a low glass transition point, and thus is easily softened. When the crystalline resin is exposed on the surface, the charge maintenance property and the heat storage property are deteriorated.

  In addition, in order to increase the dispersibility of the amorphous resin and to make it pulverizable, a toner in which an amorphous hybrid resin is combined with a crystalline resin (see, for example, Patent Document 3), a styrene acrylic resin and a crystalline property are used. A toner containing a binding resin with a polyester resin (for example, see Patent Document 4) is known, but the crystalline polyester is not sufficiently coated.

As described above, in the electrophotographic process, in order to stably maintain the performance of the toner even under various mechanical stresses, the exposure of the crystalline resin and the release agent to the surface is suppressed and the fixing property is not impaired. In addition, it is necessary to increase the surface hardness and improve the mechanical strength of the toner itself. That is, there is a demand for a toner that has excellent toner heat storage properties and excellent fixability.
JP 49-12950 A JP 2004-191927 A JP 2003-173047 A JP-A-2-294659

  An object of the present invention is to solve the above problems. That is, an object of the present invention is to provide an electrostatic charge developing toner having a wide fixing latitude and excellent in heat storage property and charging property, and a method for producing the toner.

The above-mentioned subject is achieved by the following present invention. That is, the present invention
<1> A toner for electrostatic charge image development having a core-shell structure in which a shell is provided on the surface of core particles including a binder resin containing a crystalline polyester resin and an amorphous polyester resin, and a colorant, The toner for developing an electrostatic image, wherein the core particle contains a composite resin in which a styrene resin and a polyester resin are bonded.

  <2> A toner for electrostatic charge image development having a core-shell structure in which a shell is provided on the surface of a core particle including a binder resin containing a crystalline polyester resin and an amorphous polyester resin, and a colorant, A toner for developing an electrostatic charge image, wherein the shell contains a copolymer resin of polystyrene and (meth) acryl.

  <3> The electrostatic charge image developing product according to <1>, wherein the composite resin is produced by polymerization in the presence of a titanium catalyst, and the titanium content in the whole toner is 50 to 500 ppm. Toner.

  <4> The electrostatic charge image developing toner according to any one of <1> to <3>, wherein the volume average particle diameter is 3 to 10 μm.

  <5> The electrostatic image developing toner according to any one of <1> to <4>, wherein the core particles contain a release agent.

  <6> The electrostatic charge image developing toner according to any one of <1> to <5>, wherein the shape factor (SF1) is 100 to 140.

  <7> Aggregation step of forming core aggregated particles in a dispersion containing fine particles of crystalline polyester resin, fine particles of amorphous polyester resin, and fine particles of composite resin in which a styrene resin and a polyester resin are bonded, The electrostatic charge image developing toner according to <1> above, through a shell adhesion step in which resin fine particles are adhered to the surface of the core aggregated particles to form core-shell adhesion particles, and a coalescing step in which the core-shell adhesion particles are united. A method for producing a toner for developing an electrostatic charge image.

  <8> Aggregation step of forming core aggregated particles in a dispersion containing fine particles of crystalline polyester resin and amorphous polyester resin, and a copolymer resin of polystyrene and (meth) acryl on the surface of the core aggregated particles. The electrostatic charge image developing toner according to <2> is obtained through a shell adhesion step of attaching fine particles to form core-shell adhesion particles and a coalescence step of coalescing the core-shell adhesion particles. This is a method for producing a toner for charge image development.

  According to the present invention, it is possible to provide an electrostatic charge developing toner having a wide fixing latitude and excellent in heat storage and chargeability, and a method for producing the toner.

The electrostatic image developing toner of the first aspect of the present invention (hereinafter simply referred to as “first toner”) includes a binder resin containing a crystalline polyester resin A and an amorphous polyester resin B, and a colorant. And an electrostatic charge image developing toner having a core-shell structure in which a shell is provided on the surface of the core particle, the core particle including a composite resin D in which a styrene resin and a polyester resin are bonded. Features.
The electrostatic image developing toner of the second aspect of the present invention (hereinafter simply referred to as “second toner”) includes a binder resin containing a crystalline polyester resin A and an amorphous polyester resin B; A toner for electrostatic charge image development having a core-shell structure in which a shell is provided on the surface of core particles including a colorant, wherein the shell includes a copolymer resin C of polystyrene and (meth) acryl. To do.

By including the composite resin D in the core, the first toner can improve the adhesion between the polyester resin and the shell of the core, and can easily form a good core-shell structure. And a wide fixing latitude. Further, since it contains a composite resin D that is compatible with the crystalline polyester resin A, the crystalline polyester resin A can be satisfactorily incorporated into the core particles, and a good core-shell structure is formed as described above. Therefore, exposure of the crystalline polyester resin to the surface can be prevented, and excellent heat storage properties can be obtained.
The first toner preferably contains a release agent in the core from the viewpoint of improving the fixability, and the first toner contains a composite resin D having a good compatibility with the release agent. Therefore, the release agent can be well taken into the core particles, and a good core-shell structure is formed as described above, thereby preventing the release agent from being exposed to the surface. This also provides excellent heat storage properties.

By including the copolymer resin C in the shell, the second toner can easily form a good core-shell structure, and can obtain good chargeability and a wide fixing latitude. In addition, since a good core-shell structure is formed, exposure of the crystalline polyester resin to the surface can be prevented, and excellent heat storage properties can be obtained.
In the second toner, it is preferable to contain a release agent in the core from the viewpoint of improving the fixability, and since a good core-shell structure is formed as described above, Exposure to the surface can be prevented, and this also provides excellent heat storage properties.

  In the present invention, a toner that satisfies both the conditions of the first and second aspects is particularly preferable, that is, an aspect in which the shell of the first toner contains the copolymer resin C is particularly preferable. . By containing the composite resin D in the core and the copolymer resin C in the shell, the adhesion between the core polyester resin, the shell polystyrene and the (meth) acrylic copolymer resin is very good, and the core shell is excellent. The structure is easily formed.

  Hereinafter, the constitution, components and production method of the toner of the present invention will be described in detail.

<Crystalline polyester resin A>
First, the crystalline polyester resin A, which is an essential component of the core in both the first toner and the second toner (hereinafter simply referred to as “the toner of the present invention” together), will be described.
The crystalline polyester resin A in the present invention is preferably used in the range of 5 to 50% by mass among all the components constituting the toner. When the proportion of the crystalline resin exceeds 50% by mass, good fixing characteristics can be obtained, but the phase separation structure in the fixed image becomes non-uniform, and the strength of the fixed image, particularly the scratch strength, may be reduced, and scratches may be caused. It may present problems such as being easy to stick. On the other hand, if it is less than 5%, the sharp melt property derived from the crystalline resin cannot be obtained, and simply by plasticizing the amorphous polymer, the toner blocking resistance and image storage are ensured while ensuring good low-temperature fixability. Not easy to keep sex.

  “Crystalline resin” refers to a resin having a clear endothermic peak in differential scanning calorimetry. As a specific measurement method, a thermal analysis device of a differential scanning calorimeter (manufactured by Max Science Co., Ltd .: DSC3110, thermal analysis system 001 / hereinafter, abbreviated as “DSC”) is used as the endothermic peak. The temperature was raised from room temperature to 150 ° C. at a rate of 10 ° C./min, held at 150 ° C. for 5 minutes, and then cooled to 0 ° C. at a rate of 10 ° C./min and held at 0 ° C. for 5 minutes. Thereafter, as a second temperature raising step, the temperature was raised again from 0 ° C. to 150 ° C. at a rate of 10 ° C. per minute, and measurement was performed. In the present invention, it means that the half width of the endothermic peak at that time is within 6 ° C.

The crystalline polyester resin used in the toner of the present invention is preferably synthesized from a polyvalent carboxylic acid component and a polyhydric alcohol component. In the present invention, a commercially available product may be used as the polyester resin, or an appropriately synthesized product may be used.
Examples of the polyvalent carboxylic acid component include oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12 -Aliphatic dicarboxylic acids such as dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, mesaconic acid Aromatic dicarboxylic acids such as dibasic acids and the like, and the anhydrides and lower alkyl esters thereof are also included, but not limited thereto.
Examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, and anhydrides thereof. And lower alkyl esters.

Among these polyvalent carboxylic acid components, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid from the viewpoint that sharper melting properties can be obtained. 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, and 1,18-octadecanedicarboxylic acid are preferred, and azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, and 1,10-decanedicarboxylic acid. Acid, 1,12-dodecanedicarboxylic acid is particularly preferred.
These may be used alone or in combination of two or more.

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

  On the other hand, as the polyhydric alcohol component, an aliphatic diol is preferable, and a linear aliphatic diol having 6 to 20 carbon atoms in the main chain portion is more preferable. When the aliphatic diol is branched, 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.

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

  Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like. These may be used individually by 1 type and may use 2 or more types together.

  Among the polyhydric alcohol components, the content of the aliphatic diol component is preferably 80 mol% or more, and more preferably 90 mol% or more. When the content of the aliphatic diol component 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. is there.

  If necessary, monovalent acids such as acetic acid and benzoic acid and monovalent alcohols such as cyclohexanol benzyl alcohol can also be used for the purpose of adjusting the acid value and hydroxyl value.

  The method for producing the crystalline polyester resin is not particularly limited, and can be produced by a general polyester polymerization method in which an acid component and an alcohol component are reacted. Examples thereof include direct polycondensation and transesterification. They are manufactured using different types of monomers.

  The production of the crystalline polyester resin can be carried out at a polymerization temperature of 180 to 230 ° C., and the reaction is carried out while reducing the pressure in the reaction system as necessary to remove water and alcohol generated during condensation. When the monomer is not dissolved or compatible with 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. When a monomer having poor compatibility exists in the copolymerization reaction, the monomer having poor compatibility and the monomer and the acid or alcohol to be polycondensed are condensed in advance and then polycondensed together with the main component.

The resin fine particle dispersion of crystalline polyester can be prepared by adjusting the acid value of the resin or emulsifying and dispersing using an ionic surfactant or the like.
Catalysts that can be used in the production of the crystalline polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; zinc, manganese, antimony, titanium, tin, zirconium, germanium, aluminum, etc. Metal compounds; phosphorous acid compounds, phosphoric acid compounds, amine compounds, and the like. Specific examples include the following compounds.

  For example, sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, zinc acetate, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate, titanium tetraethoxide, titanium Tetrapropoxide, titanium tetraisoproxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium tetrabutoxide, naphthenic acid Zirconium, zirconyl carbonate, zirconyl acetate, zirconyl stearate, zirconyl octylate, germanium oxide, aluminum oxide Arm, triphenyl phosphite, tris (2, 4-t-butylphenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, compounds such as triphenyl amine. From the viewpoint of reactivity, antimony, tin, and titanium are desirable, and from the viewpoint of environmental impact and safety, titanium and aluminum are desirable.

As melting | fusing point of crystalline resin, Preferably it is 50-100 degreeC, More preferably, it is 60-80 degreeC. If the melting point is lower than 50 ° C., the storage stability of the toner and the storage stability of the toner image after fixing may become a problem. There is a case.
A crystalline resin may show a plurality of melting peaks, but in the present invention, the maximum peak is regarded as the melting point.

<Amorphous polyester resin B>
Next, similarly to the crystalline polyester resin A, the amorphous polyester resin B, which is an essential component of the core in both the first toner and the second toner, will be described.
As the amorphous polyester resin B in the present invention, those obtained mainly by condensation polymerization of polyvalent carboxylic acids and polyhydric alcohols are preferable. A non-crystalline polyester resin can be easily prepared as a resin particle dispersion by adjusting the acid value of the resin or emulsifying and dispersing it using an ionic surfactant or the like.

  Examples of the polyvalent carboxylic acids 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, and alicyclic carboxylic acids such as cyclohexanedicarboxylic acid. Among these polyvalent carboxylic acids, it is preferable to use aromatic carboxylic acids, and in order to take a crosslinked structure or a branched structure in order to ensure good fixability, a trivalent or higher carboxylic acid (trivalent) is used together with a dicarboxylic acid. It is preferable to use merit acid or its acid anhydride in combination. These polyvalent carboxylic acids can be used alone or in combination of two or more.

  Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, glycerin and other aliphatic diols, cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A. And aromatic diols such as bisphenol A ethylene oxide adduct and bisphenol A propylene oxide adduct. Among these polyhydric alcohols, aromatic diols and alicyclic diols are preferable, and aromatic diols are more preferable. In order to secure good fixing properties, a trihydric or higher polyhydric alcohol (glycerin, trimethylolpropane, pentaerythritol) may be used in combination with the diol in order to take a crosslinked structure or a branched structure. These polyhydric alcohols can be used alone or in combination of two or more.

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

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

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

  The amorphous polyester resin used in the toner of the present invention has a weight average molecular weight (Mw) of 5,000 to 50,000 as measured by a gel permeation chromatography (GPC) method in which tetrahydrofuran (THF) is soluble. The molecular weight distribution (Mn) is preferably 2,000 to 10,000, and the molecular weight distribution Mw / Mn is preferably 1.5 to 10.

  When the weight average molecular weight and number average molecular weight are smaller than the above ranges, while effective for low-temperature fixability, hot offset resistance may be deteriorated, and resin strength is reduced, so that fixing to paper is possible. There is a concern that the image strength may decrease. In addition, since the glass transition point of the toner is lowered, the storage stability such as toner blocking may be adversely affected. On the other hand, if the molecular weight is larger than the above range, the hot offset resistance can be sufficiently provided, but the low-temperature fixability tends to be lowered, and the bleeding of the crystalline polyester phase existing in the toner is inhibited, so that the document May adversely affect storage. Therefore, it becomes easy to satisfy both the low-temperature fixability, the hot offset resistance, and the document storage stability by satisfying the above conditions.

  In the present invention, the molecular weight of the resin is measured with a THF solvent using a Tosoh GPC / HLC-8120, a Tosoh column / TSKgel SuperHM-M (15 cm), and a molecular weight calibration prepared with a monodisperse polystyrene standard sample. The molecular weight was calculated using a curve.

  The acid value of the polyester resin (the number of mg of KOH required to neutralize 1 g of resin) is easy to obtain the molecular weight distribution as described above, and is easy to ensure the granulation property of the toner particles by the emulsion dispersion method. From the standpoint of maintaining good environmental stability (charging stability when temperature / humidity changes) of the obtained toner and the like, it is preferably 1 to 30 mg KOH / g. The acid value of the polyester resin can be adjusted by controlling the carboxyl group at the terminal of the polyester according to the blending ratio of the raw polyhydric carboxylic acid and polyhydric alcohol and the reaction rate. Or what has a carboxyl group in the principal chain of polyester is obtained by using trimellitic anhydride as a polyvalent carboxylic acid component.

  When the first and second toners of the present invention contain the above-described crystalline polyester resin A and amorphous polyester resin B in the core, good low-temperature fixability can be obtained.

<Copolymer resin C>
Next, the copolymer resin C, which is an essential component in the shell of the second toner, will be described. In the second toner of the present invention, it is essential that the shell contains a copolymer resin C of polystyrene and (meth) acryl. In addition, it is preferable that the content rate of the copolymer resin C in a shell is 3 mass% or more, More preferably, it is 5 mass% or more, Most preferably, it is 7 mass% or more.

As the copolymer resin C in the shell provided on the surface of the core particle, at least one styrene monomer such as styrene, parachlorostyrene, α-methylstyrene, methyl acrylate, ethyl acrylate, acrylic acid n- Propyl, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, i-propyl methacrylate, Examples thereof include copolymer resins in which at least one or more acrylic or methacrylic monomers such as n-butyl methacrylate, i-butyl methacrylate, lauryl methacrylate, and 2-ethylhexyl methacrylate are combined.
Among these, at least one of styrene and α-methylstyrene as a styrene monomer, and n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate as an acrylic or methacrylic monomer A copolymer resin combining at least one of 2-ethylhexyl acrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, and 2-ethylhexyl methacrylate. In particular, a copolymer resin combining styrene and n-butyl acrylate, styrene and i-butyl acrylate, styrene and n-butyl methacrylate, styrene and 2-ethylhexyl acrylate, or styrene and 2-ethylhexyl methacrylate is preferable. preferable.

  The copolymer resin C may be copolymerized or mixed with other radical monomers or resins. Other radical monomers and resins include vinyl nitriles such as acrylonitrile and methacrylonitrile: vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether: vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone: Examples thereof include monomers and polymers such as polyolefins such as ethylene, propylene, and butadiene. Furthermore, epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, etc., non-vinyl condensation resins, or a mixture of these with the above vinyl resins, or vinyl monomers in the presence of these resins A graft polymer or the like obtained upon polymerization can also be used.

  In the copolymer resin C of polystyrene and (meth) acryl, it is preferable to contain 50-95 mass% of styrene resin. More desirably, it is 60 to 90% by mass. If the amount is too small, it is difficult to obtain hardness as a shell layer. If the amount is too large, the Tg may increase and it may be difficult to melt. Further, the mass ratio of the shell in the whole toner is preferably 5 to 40% by mass, and more preferably 10 to 30% by mass with respect to the core mass. If the amount is less than this, the surface of the core particles cannot be uniformly coated with the shell, so that the crystalline resin and the release agent are likely to be exposed on the toner surface, and there is a concern that the chargeability and powder characteristics may deteriorate. On the other hand, if the amount is larger than this, the core component at the time of fixing becomes difficult to melt, and the low-temperature fixing property may be impaired or offset may be easily caused.

  The polystyrene and (meth) acrylic copolymer resin C can be prepared by emulsion polymerization using an ionic surfactant or the like to prepare a resin fine particle dispersion. If it is oily and dissolves in a solvent with relatively low solubility in water, the resin is dissolved in those solvents and dispersed in water together with an ionic surfactant and polymer electrolyte using a disperser such as a homogenizer. Thereafter, the resin fine particle dispersion can be prepared by evaporating the solvent by heating or reducing the pressure. Alternatively, a resin particle dispersion may be prepared by adding a surfactant to the resin and emulsifying and dispersing in water with a disperser such as a homogenizer.

The resin particle diameter in the resin fine particle dispersion thus obtained is preferably 0.05 to 0.50 μm, and more preferably 0.10 to 0.30 μm. When the particle size is 0.05 μm or more, a toner having a desired size can be produced by agglomeration of the resin particles. On the other hand, when the particle size is 0.50 μm or less, the particle size distribution of the toner aggregation particles is improved. is there.
In addition, as a measuring method of this particle diameter, it can measure, for example with a laser diffraction type particle size distribution measuring apparatus (made by LA-700 Horiba Ltd.).

  The glass transition temperature of the copolymer resin C is preferably 35 to 100 ° C., and more preferably 50 to 80 ° C. from the viewpoint of the balance between storage stability and toner fixability. When the glass transition temperature is less than 35 ° C., the toner tends to be blocked during the storage or in the developing machine (a phenomenon in which toner particles are aggregated into a lump). On the other hand, if the glass transition temperature exceeds 100 ° C., the fixing temperature of the toner becomes high, which is not preferable.

Moreover, it is preferable that the softening point of the copolymer resin C exists in the range of 80-130 degreeC. More preferably, it is the range of 90-120 degreeC. When the softening point is less than 80 ° C., there is a concern that the image stability of the toner after fixing and during image storage deteriorates, and when the softening point exceeds 130 ° C., the low-temperature fixability deteriorates. There is a case.
The softening point of the amorphous polymer is a pretest: 80 ° C./300 sec, plunger pressure: 0.980665 MPa, die size: 1 mmφ × 1 mm, temperature rise using a flow tester (manufactured by Shimadzu Corporation: CFT-500C). Speed: An intermediate temperature between the melting start temperature and the melting end temperature under the condition of 3.0 ° C./min.

Further, the weight average molecular weight (Mw) of the copolymer resin C is preferably 5000 to 100,000, more preferably 10,000 to 50,000. The number average molecular weight (Mn) is preferably 1000 to 50000, and the molecular weight distribution Mw / Mn is preferably 2500 to 20000.
When the weight average molecular weight and the number average molecular weight are not less than the above lower limit value, there is an advantage that the fixability to paper as a toner is improved. There is an advantage to become.

The values of the weight average molecular weight Mw and the number average molecular weight Mn can be determined by various methods, and there are some differences depending on the measurement method, but in the present invention, the values are determined by the following measurement methods. That is, the weight average molecular weight Mw and the number average molecular weight Mn are measured by gel permeation chromatography (GPC) under the conditions described below. At a temperature of 40 ° C., a solvent (tetrahydrofuran) is flowed at a flow rate of 1.2 ml per minute, and 3 mg of a tetrahydrofuran sample solution having a concentration of 0.2 g / 20 ml is injected as a sample weight for measurement. When measuring the molecular weight of a sample, select the measurement conditions that fall within the range in which the logarithm of the molecular weight of the prepared calibration curve and the count number are linear, using several monodisperse polystyrene standard samples. .
The reliability of the measurement results is that the NBS706 polystyrene standard sample obtained under the above-described measurement conditions has a weight average molecular weight Mw = 28.8 × 10 ⁴ and a number average molecular weight Mn = 13.7 × 10 ⁴ . Can be confirmed. As the GPC column to be used, any column may be adopted as long as it satisfies the above conditions. Specifically, for example, TSK-GEL, GMH (manufactured by Tosoh Corporation) or the like can be used. The solvent and measurement temperature are not limited to the described conditions, and may be changed to appropriate conditions.

  Here, the shell in the first toner may have any conventionally known form, and is not particularly limited. However, the shell containing the copolymer resin C of polystyrene and (meth) acrylic is not limited. It is particularly preferred that When the shell in the first toner contains the copolymer resin C, a better core-shell structure can be easily formed.

<Composite resin D>
The production method of the composite resin D in which the styrenic resin and the polyester resin used in the toner of the present invention are bonded is as follows: (1) When the polyester is polycondensed, a monomer having radical bondability is added to After the polycondensation, a method of polymerizing a polyester containing a styrene-based monomer and the above-mentioned polycondensed monomer having radical bondability, or (2) a carboxylic acid or an alcohol component-containing radical polymerizable compound and styrene copolymerized with styrene. A method of polycondensation of a styrene copolymer having an acid or alcohol component together with a polyhydric alcohol and a polycarboxylic acid, or (3) when polymerizing a styrene resin and a polyester resin, both reactive groups And a method of reacting a styrene resin and a polyester resin.
The method (1) is particularly desirable since a resin dispersion can be easily prepared and the final step can be carried out by emulsion polymerization.

Hereinafter, a method for producing the composite resin D by the method (1) will be described.
Examples of the monomer having a radical bond include carboxylic acids having an unsaturated bond such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, oleic acid, linoleic acid, and linolenic acid. Among these, Acrylic acid, methacrylic acid and maleic acid are particularly preferably used.
With respect to the polyhydric alcohol and polyvalent carboxylic acid, the monomers mentioned for the crystalline polyester resin A and the amorphous polyester resin B can be used, and preferred examples thereof are also the same as described above.

  The “method of polycondensing polyester by adding a monomer having radical bonding property when polycondensing polyester” can be carried out by a condensation reaction according to a conventional method. As an example, the above polyhydric alcohol, polyvalent carboxylic acid, radical-bonding monomer and catalyst are added and blended in a reaction vessel equipped with a thermometer, a stirrer, a flow-down condenser, and an inert gas (nitrogen gas, etc.) ) In the presence of), and continuously remove low-molecular compounds produced as a by-product out of the reaction system. When a predetermined acid value is reached, the reaction is stopped, cooled, and the target. This can be done by obtaining the reactant.

As the catalyst used for the synthesis of this polyester resin, antimony-based, tin-based, titanium-based, aluminum-based catalysts can be used, for example, organic metals such as dibutyltin dilaurate and dibutyltin oxide, titanium tetramethoxide, Examples thereof include metal alkoxides such as titanium tetraethoxide, titanium tetrapropoxide, titanium tetraisoproxide, and titanium tetrabutoxide, and esterification catalysts such as titanium dioxide. From the viewpoints of environmental impact and safety, titanium and aluminum are desirable, and titanium is more desirable in terms of reactivity. Specifically, titanium tetrapropoxide, titanium tetrabutoxide, and titanium dioxide are particularly desirable.
The amount of such a catalyst added is preferably 0.01 to 1.00% by mass relative to the total amount of raw materials.

Next, the obtained polyester having radical polymerizability and a styrene compound are emulsion-polymerized to obtain a composite resin D in which the styrene resin and the polyester resin are bonded.
Examples of the styrenic compound include the styrenic monomers listed in the section of the copolymer resin C, and preferred examples thereof are the same as those described above. Moreover, you may copolymerize a (meth) acryl compound or another vinyl type compound.

  The emulsion polymerization method can be carried out in the same manner as for the copolymer resin C, and emulsion polymerization can be carried out using an ionic surfactant or the like to produce a resin fine particle dispersion. Also, if it is oily and dissolves in a solvent with relatively low solubility in water, the resin is dissolved in those solvents and dispersed in water together with an ionic surfactant and polymer electrolyte using a disperser such as a homogenizer. Then, the resin fine particle dispersion can be prepared by evaporating the solvent by heating or decompressing. Alternatively, a resin particle dispersion may be prepared by adding a surfactant to the resin and emulsifying and dispersing in water with a disperser such as a homogenizer.

The resin particle diameter in the resin fine particle dispersion thus obtained is preferably 0.05 to 0.50 μm, and more preferably 0.10 to 0.30 μm. When the particle size is 0.05 μm or more, a toner having a desired size can be produced by agglomeration of the resin particles. On the other hand, when the particle size is 0.50 μm or less, there is an advantage that the particle size distribution of the toner aggregation particles is improved.
In addition, as a measuring method of this particle diameter, it can measure, for example with a laser diffraction type particle size distribution measuring apparatus (made by LA-700 Horiba Ltd.).

  The amount of polystyrene in the composite resin D in which the polystyrene resin and the polyester resin are bonded is preferably 25 to 80% by mass (that is, the amount of polyester is 20 to 75% by mass). When the amount of polystyrene is small, the adhesion of the shell is deteriorated, and there is a concern that the shell is not sufficiently covered and the heat storage property and the chargeability are deteriorated. On the other hand, if the amount is too large, the core particles are difficult to melt and the low-temperature fixability may deteriorate.

The composite resin D preferably has a weight average molecular weight (Mw) of 5,000 to 100,000, more preferably 10,000 to 500,000. The number average molecular weight (Mn) is preferably 1000 to 50000, and the molecular weight distribution Mw / Mn is preferably 2500 to 20000.
The measurement of the weight average molecular weight Mw and the number average molecular weight Mn is the same as in the case of the copolymer resin C.

  The content of the composite resin D in the first toner is desirably 3 to 30% by mass, and more preferably 5 to 15% by mass. When the amount is too small, the adhesion of the shell may be deteriorated. When the amount is too large, the toner is hardly melted, and there is a concern that the low-temperature fixability is deteriorated.

<Other additives>
-Release agent-
In the first and second toners of the present invention, it is preferable to give a release agent to the core from the viewpoint of improving the fixability. The release agent used is not particularly limited as long as it is a known release agent. For example, natural waxes such as carnauba wax, rice wax, and candelilla wax, low molecular weight polypropylene, low molecular weight polyethylene, sasol wax, Examples include, but are not limited to, synthetic such as microcrystalline wax, Fischer-Tropsch wax, paraffin wax, and montan wax, or mineral / petroleum wax, higher fatty acids such as stearic acid and palmitic acid, and synthetic ester wax. . Moreover, these mold release agents may be used individually by 1 type, and may be used together 2 or more types. Of these, use of paraffin wax, carnauba wax, modified wax thereof, and synthetic ester wax is preferred.

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

  The content of the release agent is preferably in the range of 2 to 30 parts by mass and more preferably in the range of 5 to 20 parts by mass with respect to 100 parts by mass of the binder resin. If the content of the release agent is small, there is no effect of adding the release agent, which may cause hot offset at a high temperature. On the other hand, when the amount is too large, the charging property is deteriorated and the strength of the toner is decreased, so that the toner is easily broken and may cause carrier contamination.

-Colorant-
The colorant used in the toner of the present invention is not particularly limited as long as it is a known colorant, and examples thereof include carbon black such as furnace black, channel black, acetylene black, and thermal black, bengara, bitumen, and titanium oxide. Inorganic pigments, fast yellow, disazo yellow, pyrazolone red, chelate red, brilliant carmine, para brown and other azo pigments, copper phthalocyanine, metal-free phthalocyanine and other phthalocyanine pigments, flavantron yellow, dibromoanthrone orange, perylene red, quinacridone red, Examples thereof include condensed polycyclic pigments such as dioxazine violet.

  Chrome Yellow, Hansa Yellow, Benzidine Yellow, Slen Yellow, Quinoline Yellow, Permanent Orange GTR, Pyrarozone Orange, Vulcan Orange, Watch Young Red, Permanent Red, Dupont Oil Red, Resol Red, Rhodamine B Lake, Lake Red C, Rose Bengal, aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxalate, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment 57: 1, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 74, C.I. I. Pigment blue 15: 1, C.I. I. Examples thereof include various pigments such as CI Pigment Blue 15: 3, and these can be used alone or in combination of two or more.

  In the electrophotographic toner of the present invention, the content of the colorant is preferably 1 to 30 parts by mass with respect to 100 parts by mass of the binder resin. It is also effective to use a pigment dispersant. By appropriately selecting the type of the colorant, yellow toner, magenta toner, cyan toner, black toner and the like can be obtained.

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

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

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

<Toner production method>
The toner of the present invention generates toner particles in an acidic or alkaline aqueous medium such as agglomeration and coalescence method, suspension polymerization method, solution suspension granulation method, solution suspension method, and solution emulsion aggregation method. It is preferable to manufacture by the wet manufacturing method, but the aggregation coalescence method is particularly preferable.

That is, an aggregation step of forming core aggregated particles in a dispersion containing fine particles of crystalline polyester resin A and fine particles of amorphous polyester resin B, and the resin particles are adhered to the surface of the core aggregated particles to form core-shell adhered particles. An aggregation coalescence method comprising a shell adhesion step and a coalescence step for coalescence of the core-shell adhesion particles, wherein the first toner is produced by using a styrene resin and polyester in the dispersion in the aggregation step A production method including fine particles of the composite resin D bonded to the resin is preferable.
Further, as the second toner manufacturing method, in the shell attaching step, the resin fine particles to be attached to the surface of the core aggregated particles are resin fine particles containing a copolymer resin C of polystyrene and (meth) acryl. The method is preferred.

  Furthermore, as a method for producing a toner of a preferred embodiment of the present invention, in the shell attaching step in the first toner producing method, the resin fine particles to be attached to the surface of the core aggregated particles are co-polymerized with polystyrene and (meth) acryl. A production method which is resin fine particles containing the polymerized resin C is preferably used.

Hereafter, an example of the manufacturing method by the aggregation coalescence method in this invention is demonstrated.
The agglomeration coalescence method includes a resin fine particle dispersion in which crystalline polyester resin A fine particles and amorphous polyester resin B fine particles of 1 μm or less are dispersed and mixed, a colorant dispersion, and a release agent in which release agent fine particles are dispersed. An agglomeration step of mixing the agent fine particle dispersion and the composite resin D fine particle dispersion in which polystyrene and polyester are bonded to form core agglomerated particles, and a copolymer resin of polystyrene and (meth) acryl after the agglomeration step A shell adhering step for adding C fine particles to adhere to the surface of the agglomerated particles, a step of adjusting the pH in the agglomerated system to stop the agglomeration growth, and the agglomerated particles at a temperature higher than the glass transition point of the resin fine particles. This is a method for producing a toner for developing an electrostatic latent image, comprising a fusing and fusing step for fusing and fusing, followed by washing and drying.

  In the aggregation step, the polymer of at least one metal salt added at the time of mixing each dispersion is a polymer of a tetravalent aluminum salt or a tetravalent aluminum salt polymer. And a trivalent aluminum salt polymer are preferred, and specific examples of these polymers include inorganic metal salts such as calcium nitrate or polymers of inorganic metal salts such as polyaluminum chloride. It is done. The metal salt polymer is preferably added so that its concentration is 0.11 to 0.25% by mass. The particle diameters of the crystalline polyester resin A fine particles, the amorphous polyester resin B fine particles, the composite resin D fine particles, the colorant fine particles, and the release agent fine particles used in the agglomeration step are the desired values for the toner diameter and the particle size distribution. In order to facilitate the adjustment, the thickness is preferably 1 μm or less, and more preferably in the range of 20 to 300 nm. In addition, the aggregation process and the shell adhesion process may be performed repeatedly in a plurality of stages.

Next, in the fusion / unification step, the core / shell aggregated particles obtained through the aggregation step are dissolved in a melting point of the crystalline polyester resin A contained in the core / shell aggregated particles, amorphous. The toner is obtained by heating above the glass transition temperature of the cohesive polyester resin B, the polystyrene and (meth) acrylic copolymer resin C, and the composite resin D, and fusing and coalescing.
After completion of the aggregation and fusion, a desired toner is obtained through an arbitrary washing step, solid-liquid separation step, and drying step. In the washing step, it is preferable to sufficiently perform substitution washing with ion-exchanged water from the viewpoint of chargeability. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration, and the like are preferably used from the viewpoint of productivity. Further, although the drying process is not particularly limited, freeze drying, flash jet drying, fluidized drying, vibration fluidized drying and the like are preferably used from the viewpoint of productivity.

<Physical properties of toner>
-Titanium content in toner-
The composite resin D used in the first toner of the present invention is particularly preferably polymerized under a titanium catalyst as described above, and the first toner has a titanium content of 50 to 500 ppm (mass by mass). Ratio). Furthermore, it is more preferable that it is 70-300 ppm, and it is especially preferable that it is 100-250 ppm. If the titanium content is 50 ppm or more, the polymerization reaction tends to proceed. On the other hand, if the titanium content is 500 ppm or less, the amount of titanium remaining in the toner is reduced, and toner characteristics such as charging are not impaired.

  The titanium content in the toner was quantified by the following method. 10 g of toner is dissolved in 100 g of chloroform, and the supernatant is collected after being left for 48 hours. 0.25 g of a dried product of chloroform-soluble matter obtained by drying the collected supernatant is put into a 25 ml volumetric flask, and 5 ml of chloroform is added and dissolved. After dissolution, the sample is prepared by adding xylene to the marked line of the volumetric flask to prepare a sample, and using a high frequency inductively coupled plasma emission spectrometer (IPC-AES, manufactured by Seiko Electronics Co., Ltd., SPS1200VR), a diffraction grating : Main spectrometer 3600 lines / mm, slit: incident 20 μm, output 40 μm, photomar: R306, torch: organic solvent torch, nebulizer: glass concentric, argon gas flow rate: plasma gas 18 liter / min, auxiliary gas 1.8 Under the conditions of liter / minute, carrier gas 0.11 MPa, RF power: 1.8 kW, analysis wavelength: 334.9 nm, photometric height: 15 mm, integration time: 1 second, number of integrations 3 times, the titanium standard solution is Using Metalo-Organic Standard (5000 μg / g) manufactured by Conostan It was quantified.

-Average particle size and particle size distribution of toner-
The toner of the present invention preferably has a volume average particle size of 3 to 10 μm, more preferably 4 to 9 μm, and particularly preferably 5 to 8 μm from the viewpoint of forming good image quality.

  The particle size and particle size distribution index of the toner for developing an electrostatic charge image of the present invention are measured using a measuring instrument such as Coulter Counter TAII (manufactured by Nikka Kisha Co., Ltd.), Multisizer II (manufactured by Nikka Kisha Co., Ltd.) or the like. With respect to the particle size range (channel) into which the particle size distribution to be measured is divided, a cumulative distribution is drawn from the smaller diameter side for each volume and number, and the particle size at which 50% is accumulated is defined as the volume average particle size D50. In addition, the volume average particle size distribution index (GSDv) is calculated by using the values of the particle size D16% to be accumulated 16%, the particle size D16% to be accumulated 16%, and the particle size D84% (D84% / D16%). Was obtained as a volume average particle size distribution index GSDv.

-Toner charge amount-
The charge amount of the electrostatic charge developing toner of the present invention is preferably 20 to 55 μC / g, more preferably 25 to 45 μC / g. If the charge amount is less than 20 μC / g, background stains (fogging) are likely to occur, and if it exceeds 55 μC / g, the image density tends to decrease.
The measuring method will be described later.

-Toner shape factor-
The toner has a shape factor (SF1) of preferably 100 to 140, more preferably 100 to 130, and particularly preferably 100 to 120. If it is larger than the above range, transferability may be deteriorated.
SF1 is measured by taking an optical microscope image of toner spread on a slide glass into a Luzex image analyzer through a video camera, and calculating the square / projection area (ML2 / A) of the circumference of 50 or more toners. The shape factor (SF1) was calculated from the average value.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not specifically limited to these.
First, examples of methods for preparing each material and methods for producing aggregated particles will be described. In the following examples, “part” represents “part by mass” unless otherwise specified.

[Synthesis of resin materials]
-Preparation of crystalline polyester resin (A-1) dispersion-
In a heat-dried three-necked flask, an acidic component composed of 98 mol% dimethyl sebacate and 2 mol% dimethyl-5-sulfonate sodium and an alcohol component composed of ethylene glycol were added at a molar ratio of 1: 1. After 0.2% by mass of titanium tetrabutoxide (catalyst) is added to these polyester components, the air in the container is brought into an inert atmosphere with nitrogen gas by depressurization and stirred at 180 ° C. for 5 hours with mechanical stirring. Reflux was performed.
Thereafter, excess ethylene glycol was removed by distillation under reduced pressure, the temperature was gradually raised to 230 ° C., and the mixture was stirred for 2 hours. When it became a viscous state, it was air-cooled, the reaction was stopped, and a crystalline polyester resin (A- 1) was synthesized. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (A-1) was 9800 by molecular weight measurement (polystyrene conversion) by gel permeation chromatography.

Next, a crystalline fine particle resin (A-1) was used to prepare a resin fine particle dispersion.
Crystalline polyester resin (A-1) 90 parts Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 1.8 parts Ion-exchanged water 210 parts After sufficiently dispersing, dispersion treatment was performed for 1 hour with a pressure discharge type gorin homogenizer to obtain a crystalline polyester resin (A-1) dispersion having a center diameter of 235 nm and a solid content of 30% by mass.

-Preparation of crystalline polyester resin (A-2) dispersion-
In a heat-dried three-necked flask, dimethyl sebacate (acidic component) and 1,10-dodecanediol (alcohol component) are added at a molar ratio of 98: 100, and 0.3% by mass with respect to these polyester components. After adding titanium tetrabutoxide (catalyst), the air in the container was brought into an inert atmosphere with nitrogen gas by depressurization, and stirred and refluxed at 180 ° C. for 5 hours with mechanical stirring.
Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 4 hours. When the mixture became viscous, it was air-cooled, the reaction was stopped, and a crystalline polyester resin (A-2) was synthesized. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (A-2) was 24000 by molecular weight measurement (polystyrene conversion) by gel permeation chromatography.

Next, a resin fine particle dispersion was prepared using the crystalline polyester resin (A-2).
Crystalline polyester resin (A-2) 90 parts Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.) 2.2 parts Ion-exchange water 210 parts After sufficiently dispersing, dispersion treatment was performed for 1 hour with a pressure discharge type gorin homogenizer to obtain a crystalline polyester resin (A-2) dispersion having a center diameter of 130 nm and a solid content of 30% by mass.

-Preparation of crystalline polyester resin (A-3) dispersion-
In a heat-dried three-necked flask, 1,10-dodecane diacid (acidic component) and 1,9-nonanediol (alcohol component) are added in a molar ratio of 91: 100, and further, the polyester component is added in an amount of 0.1. After 3% by mass of titanium tetrabutoxide (catalyst) was added, the air in the container was brought into an inert atmosphere with nitrogen gas by depressurization, and the mixture was stirred and refluxed at 180 ° C. for 6 hours with mechanical stirring.
Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 4 hours. When the mixture became viscous, it was air-cooled, the reaction was stopped, and a crystalline polyester resin (A-3) was synthesized. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (A-3) was 14000 by molecular weight measurement (polystyrene conversion) by gel permeation chromatography.

Next, a crystalline fine particle resin (A-3) was used to prepare a resin fine particle dispersion.
Crystalline polyester resin (A-3) 90 parts Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.) 2.2 parts Ion-exchanged water 210 parts or more are heated to 100 ° C., and IKA Ultra Turrax T50 is used. After sufficiently dispersing, dispersion treatment was performed for 1 hour with a pressure discharge type gorin homogenizer to obtain a crystalline polyester resin (A-3) dispersion having a center diameter of 130 nm and a solid content of 30% by mass.

-Preparation of Amorphous Polyester Resin (B-1) Dispersion-
Terephthalic acid 39.6 mol%
Isophthalic acid 9.9 mol%
Dimethyl-5-sulfonic acid sodium isophthalate 1.0 mol%
Bisphenol A ethylene oxide 2-mol adduct 14.9 mol%
Bisphenol A propylene oxide adduct 34.6 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying tower, and the temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. After confirming the above, 1.2% by mass of titanium tetrabutoxide (catalyst) was added to the polyester component. Further, while distilling off the produced water, the temperature was increased to 240 ° C. over 6 hours from the same temperature, and the dehydration condensation reaction was continued at 240 ° C. for another 3 hours. An amorphous polyester resin having a weight average molecular weight of 11000 ( B-1) was obtained.

Subsequently, this was transferred in a molten state to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) at a rate of 100 g / min. Separately prepared aqueous medium tank is filled with 0.37 wt% diluted ammonia water diluted with ion-exchanged water with reagent-exchanged water, and heated at 120 ° C with a heat exchanger at a rate of 0.1 liter per minute. The amorphous polyester resin (B-1) melt was transferred to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.).
Cavityron is operated under conditions of a rotor rotation speed of 60 Hz and a pressure of 5 kg / cm ² , and is made of amorphous polyester resin (B-1) having an average particle size of 0.15 μm and a solid content of 30% by mass. A polyester resin (B-1) dispersion was obtained.

-Preparation of Amorphous Polyester Resin (B-2) Dispersion-
Terephthalic acid 40mol%
Isophthalic acid 10mol%
Bisphenol A ethylene oxide 2-mol adduct 25 mol%
Bisphenol A propylene oxide adduct 20 mol%
Cyclohexanedimethanol 5 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying tower, and the temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. After confirming the above, 1.2% by mass of titanium tetrabutoxide (catalyst) was added to the polyester component. Further, while distilling off the generated water, the temperature was increased to 240 ° C. over 6 hours from the same temperature, and the dehydration condensation reaction was continued at 240 ° C. for another 3 hours, whereby an amorphous polyester resin having a weight average molecular weight of 9200 ( B-2) was obtained.

  Next, 100 parts of an amorphous polyester resin (B-2) was dissolved in 50 parts of ethyl acetate and 20 parts of isopropanol, 3 parts of a 10% by mass aqueous ammonia solution was added, and water was added while stirring. After dripping a part, the solvent was distilled off by the evaporator and the amorphous polyester resin (B-2) dispersion liquid was obtained.

-Preparation of Copolymer Resin (C-1) Dispersion of Polystyrene and (Meth) Acrylic-
340 parts of styrene, 60 parts of n-butyl acrylate, 4 parts of acrylic acid, and 20 parts of dodecanethiol are mixed and dissolved in 15 parts of anionic surfactant Neogen SC (Daiichi Kogyo Seiyaku) in 760 parts of ion-exchanged water. After being dissolved and emulsified, 4 parts of ammonium persulfate dissolved in 20 parts of ion-exchanged water was added. After purging with nitrogen, the solution was heated to 70 ° C. with stirring and reacted for 5 hours. It was. A polystyrene and acrylic copolymer resin (C-1) dispersion having an average particle size of 0.18 μm, a glass transition point of 62.5 ° C., and a weight average molecular weight of 26000 was obtained.

-Preparation of Copolymer Resin (C-2) Dispersion of Polystyrene and (Meth) Acrylic-
After mixing 250 parts of styrene, 150 parts of n-butyl methacrylate, 4 parts of acrylic acid and 20 parts of dodecanethiol, 15 parts of anionic surfactant Neogen SC (Daiichi Kogyo Seiyaku) was dissolved in 760 parts of ion-exchanged water. After emulsifying and adding 4 parts of ammonium persulfate dissolved in 20 parts of ion-exchanged water, the mixture was purged with nitrogen, heated to a liquid temperature of 70 ° C. with stirring, and reacted for 5 hours. A polystyrene and acrylic copolymer resin (C-2) dispersion having an average particle size of 0.16 μm, a glass transition point of 64.5 ° C., and a weight average molecular weight of 24,000 was obtained.

-Preparation of polystyrene / polyester composite resin (D-1) dispersion-
Terephthalic acid 35mol%
Isophthalic acid 10mol%
Maleic anhydride 5 mol%
Bisphenol A ethylene oxide 2 mol adduct 15 mol%
Bisphenol A propylene oxide adduct 35 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying tower, and the temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. After confirming the above, 1.5% by mass of titanium tetrabutoxide (catalyst) was added to the polyester component. Further, 5 hours from the same temperature was required while distilling off the generated water, the temperature was raised to 230 ° C., and a dehydration condensation reaction was further performed at 340 ° C. for 3 hours to obtain a polyester. Next, 100 parts of the obtained polyester, 300 parts of styrene, 100 parts of n-butyl acrylate, 3 parts of acrylic acid, and 16 parts of dodecanethiol were mixed and heated to dissolve the polyester, and then the anionic surfactant Neogen SC. (Daiichi Kogyo Seiyaku) 18 parts dissolved in 1050 parts of ion-exchanged water was added and emulsified, 5 parts of ammonium persulfate dissolved in 20 parts of ion-exchanged water was added, and the mixture was purged with nitrogen and stirred. The solution was heated to 70 ° C. and reacted for 5 hours. A polystyrene / polyester composite resin (D-1) dispersion having an average particle size of 0.21 μm, a glass transition point of 56.5 ° C., and a weight average molecular weight of 15000 was obtained. After the resin dispersion was freeze-dried and dried under reduced pressure, the amount of titanium contained in the resin was measured and found to be 180 ppm.

-Preparation of polystyrene / polyester composite resin (D-2) dispersion-
Terephthalic acid 32.5mol%
Isophthalic acid 7.5mol%
Maleic anhydride 10.0 mol%
Bisphenol A ethylene oxide 2-mol adduct 10.0 mol%
Bisphenol A propylene oxide adduct 40.0 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying tower, and the temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. Then, 2.5% by mass of titanium tetra i-propoxide (catalyst) was added to the polyester component. Further, 5 hours from the same temperature was required while distilling off the generated water, the temperature was raised to 230 ° C., and a dehydration condensation reaction was further performed at 340 ° C. for 3 hours to obtain a polyester. Next, 150 parts of the obtained polyester, 260 parts of styrene, 40 parts of n-butyl acrylate, 3 parts of acrylic acid and 16 parts of dodecanethiol were mixed and heated to dissolve the polyester, and then the anionic surfactant Neogen SC. (Daiichi Kogyo Seiyaku Co., Ltd.) 18 parts dissolved in 800 parts of ion-exchanged water and emulsified, and then added 5 parts of ammonium persulfate dissolved in ion-exchanged water. The mixture was heated to a liquid temperature of 70 ° C. and reacted for 5 hours. A polystyrene / polyester composite resin (D-2) dispersion having an average particle size of 0.24 μm, a glass transition point of 57.5 ° C., and a weight average molecular weight of 17,000 was obtained. After the resin dispersion was freeze-dried and dried under reduced pressure, the amount of titanium contained in the resin was measured and found to be 270 ppm.

-Preparation of colorant dispersion-
(Preparation of cyan colorant dispersion)
Copper phthalocyanine B15: 3 (manufactured by Dainichi Seika) 45 parts Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.) 5 parts Ion-exchanged water 200 parts The above is mixed and dissolved, and dispersed for 10 minutes with a homogenizer (IKA Ultra Tarrax) Thus, a cyan colorant dispersion having a center particle size of 175 nm and a solid content of 22.5% by mass was obtained.

(Preparation of yellow colorant dispersion)
C. I. Pigment Yellow 74 (manufactured by Clariant) 60 parts Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 7 parts Ion-exchanged water 200 parts The above components are mixed and dissolved, dispersed with a homogenizer (IKA Ultra Tarrax) for 10 minutes, and a center particle size of 150 nm A yellow colorant dispersion having a solid content of 24.5% by mass was obtained.

(Preparation of magenta colorant dispersion)
C. I. Pigment Red 122 (manufactured by Clariant) 50 parts Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 6 parts Ion-exchanged water 200 parts The above components are mixed and dissolved, dispersed with a homogenizer (IKA Ultra Tarrax) for 10 minutes, and a center particle size of 185 nm. A yellow colorant dispersion having a solid content of 23.5% by mass was obtained.

(Preparation of black colorant dispersion)
Carbon black Regal 330 (Cabot) 50 parts Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 6 parts Ion-exchanged water 200 parts The above is mixed and dissolved, and dispersed for 10 minutes with a homogenizer (IKA Ultra Tarrax). A black colorant dispersion having a central particle size of 240 nm and a solid content of 24.0% by mass was obtained.

-Preparation of release agent dispersion (W-1)-
Pentaerythritol behenate ester wax (melting point 84.5 ° C) 45 parts Cationic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.) 5 parts Ion-exchanged water 200 parts After sufficiently dispersing at T50, the mixture was dispersed with a pressure discharge type gorin homogenizer to obtain a release agent dispersion (W-1) having a center diameter of 215 nm and a solid content of 19.5% by mass.

-Preparation of mold release agent dispersion (W-2)-
Paraffin wax HNP-9 (Nippon Seiki, melting point 75 ° C.) 45 parts Cationic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 5 parts Ion-exchanged water 200 parts Was sufficiently dispersed in a pressure discharge type gorin homogenizer to obtain a release agent dispersion (W-2) having a center diameter of 190 nm and a solid content of 20% by mass.

-Preparation of release agent dispersion (W-3)-
Carnauba wax (melting point 81 ° C.) 45 parts Cationic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 5 parts Ion-exchanged water 200 parts After heating to 95 ° C. and fully dispersed with IKA Ultra-Turrax T50 Then, dispersion treatment was performed with a pressure discharge type gorin homogenizer to obtain a release agent dispersion (W-3) having a center diameter of 200 nm and a solid content of 20% by mass.

[Example 1]
-Production of toner particles (1)-
Crystalline polyester resin (A-1) dispersion 100 parts Amorphous polyester resin (B-1) dispersion 170 parts Polystyrene / polyester composite resin (D-1) dispersion 50 parts Cyan colorant dispersion 60 parts Release Agent (W-1) Dispersion 30 parts The above was sufficiently mixed and dispersed in a round stainless steel flask with Ultra Turrax T50. Next, 0.22 part of polyaluminum chloride was added thereto, and the dispersion operation was continued with an ultra turrax. The flask was heated to 45 ° C. with stirring in an oil bath for heating. After maintaining at 45 ° C. for 60 minutes, 60 parts of a polystyrene / acrylic copolymer resin (C-1) dispersion was added thereto. Thereafter, the pH was adjusted to 9.0 with an aqueous sodium hydroxide solution, and then the stainless steel flask was sealed, heated to 96 ° C. with continuous stirring, and maintained for 5 hours. After completion of the reaction, the mixture was cooled, filtered, sufficiently washed with ion exchange water, and then subjected to solid-liquid separation by Nutsche suction filtration. Next, vacuum drying was performed.
The particle diameter at this time was measured with a Coulter counter by the method described above. The volume average diameter D50 was 6.2 μm, and the particle size distribution coefficient GSDv was 1.25. In addition, the particle shape factor SF1 obtained from the shape observation by Luzex using the above-described method was 119.

-Preparation of external additive toner (1)-
Next, an external toner was prepared. To 100 parts of the toner particles (1) obtained above as toner base particles, 1.0 part of titanium oxide (average particle size 20 nm, n-decyltrimethoxysilane treatment), silica (volume average particle size 40 nm, silicone oil treatment) After adding 2.0 parts and blending for 15 minutes at a peripheral speed of 30 m / s using a 5 liter Henschel mixer, coarse particles are removed using a sieve having an opening of 45 μm, and the externally added toner (1) is removed. Produced.

[Examples 2 to 6]
Externally added toners (2) to (6) were produced in the same manner as in Example 1 except that the composition of each material in Example 1 was changed as described in Tables 1 and 2.

  Here, in Tables 1 and 2, the addition amount refers to the addition amount of each dispersion. The content ratio (mass% / toner) in the crystalline polyester resin A, the amorphous polyester resin B, and the composite resin D is the crystalline polyester resin A, the amorphous polyester resin B, and the composite resin in all the components of the toner. The content ratio of D in the mold release agent and the colorant (% by mass, relative to the resin) is the mold release agent for the resin components (crystalline polyester resin A, amorphous polyester resin B and composite resin D). The content ratio of the colorant, and the content ratio (% by mass, relative to the core) in the copolymer resin C refers to the content ratio of the copolymer resin C to all the components of the core.

Example 7
Except that the composite resin (D-1) dispersion in Example 3 was changed to a composite resin (D-3) dispersion in which the catalyst (titanium tetrabutoxide) used was replaced with antimony, the same procedure as in Example 3 was performed. External toner (7) was prepared.

[Comparative Example 1]
In Example 2, externally added toner (8) was produced in the same manner as Example 2 except that the crystalline polyester resin (A-2) dispersion was not added.

[Comparative Example 2]
In Example 1, the composite resin (D-1) dispersion was not added. Instead, the amount of the crystalline polyester resin (A-1) dispersion was changed from 100 parts to 125 parts (28% / toner). The amount of the polyester resin (B-1) dispersion was changed from 170 parts to 195 parts (42% / toner), and the copolymer resin (C-1) dispersion used for forming the shell was changed to amorphous polyester. Externally added toner (9) was prepared in the same manner as in Example 1 except that the resin (B-1) dispersion was used.

[Toner evaluation results]
-Toner chargeability-
The charge amount of each toner obtained as described above was measured by the following method to evaluate the chargeability.
1.5 parts of toner and 30 parts of ferrite particles (average particle size 35 μm) coated with styrene / methyl methacrylate resin are weighed into a glass bottle with a lid, under high temperature and high humidity (temperature 28 ° C., humidity 85%), and After seasoning for 24 hours under low temperature and low humidity (temperature 10 ° C., humidity 15%), the mixture was stirred and shaken with a turbula mixer for 5 minutes. The charge amount (μC / g) of the toner in both environments was measured with a blow-off charge amount measuring device. Further, the charge retention after the toner stirred with a turbula mixer was allowed to stand in both environments for 24 hours was measured in the same manner to confirm the charge retention.
As for the chargeability, the charge amount in any environment after initial and after standing was evaluated as “◯” for 25 to 55 μC / g, “Δ” for 20 to 24 μC / g, and “X” for less than 20 μC / g.

-Measurement of powder characteristics-
Using a powder tester (manufactured by Hosokawa Micron Corporation), 53 μm, 45 μm, and 38 μm openings are arranged in series from the top, and a toner for developing an electrostatic charge image as a sample is put on the 53 μm sieve, and the amplitude is 1 mm. A vibration was applied for 90 seconds, and the toner mass on each sieve after vibration was measured, added with weights of 0.5, 0.3, and 0.1, respectively, and calculated as a percentage. The degree of thermal aggregation was measured using a toner that was allowed to stand for about 24 hours in an environment of 50 ° C./50% RH, and the measurement was performed in an environment of 25 ° C./50% RH.
As for the powder characteristics, the degree of thermal aggregation is 30 or less, ◯, 30 to 39 is Δ, and 40 or more is x.

-Toner fixability-
A two-component developer is prepared by mixing 5 parts of toner and 100 parts of ferrite particles (average particle size 35 μm) coated with styrene / methyl methacrylate resin, and this is prepared as an electrophotographic copying machine Docu Center Color 400 (manufactured by Fuji Xerox Co., Ltd.). ) An image was obtained using a modified machine (modified so that the fixing temperature can be fixed by an external fixing machine), and an unfixed image was obtained.

Next, using a belt nip type external fixing device, the fixing temperature of the image and the hot offset property were evaluated while gradually increasing the fixing temperature between 100 ° C. and 200 ° C.
The low-temperature fixability is determined by fixing an unfixed solid image (25 mm × 25 mm), bending it with a weight under a certain load, and grading the degree of image defect of the portion, and more specifically (more specifically, Is a temperature at which the fixing temperature at which the image defect width of the portion becomes 1 mm or less is the minimum fixing temperature, and is used as an index for low temperature fixing properties. In the evaluation of the low-temperature fixability, a minimum fixing temperature of 120 ° C. or lower was evaluated as “◯”, 120 to 140 ° C. as Δ, and 150 ° C. or higher as ×.

For hot offset, the highest temperature at which no hot offset occurred was obtained, and the hot offset non-occurrence temperature minus the lowest fixing temperature was obtained as a temperature range in which fixing can be performed without occurrence of hot offset. The fixable temperature range is 40 ° C. or higher for ◯, 30 to 39 ° C. for Δ, and 20 ° C. or lower for X.
Table 3 shows the evaluation results of the toner. The titanium content is the content of the entire toner.

  When the fixed images of the samples that were fixed at 150 ° C. were viewed, clean fixed images were obtained in the samples of Examples 1 to 6 and Comparative Examples 1 and 2. On the other hand, in the sample of Example 7 in which antimony was used as the catalyst in the composite resin D, the color of the fixed image was slightly grayish.

Claims (4)

A toner for developing an electrostatic charge image having a core-shell structure in which a shell is provided on the surface of a core particle including a binder resin containing a crystalline polyester resin and an amorphous polyester resin, and a colorant,
The toner for developing an electrostatic charge image, wherein the core particles include a composite resin in which a styrene resin and a polyester resin are bonded. A toner for developing an electrostatic charge image having a core-shell structure in which a shell is provided on the surface of a core particle including a binder resin containing a crystalline polyester resin and an amorphous polyester resin, and a colorant,
A toner for developing an electrostatic image, wherein the shell contains a copolymer resin of polystyrene and (meth) acryl.   An aggregating step for forming core agglomerated particles in a dispersion containing fine particles of a crystalline polyester resin, fine particles of an amorphous polyester resin, and fine particles of a composite resin in which a styrene resin and a polyester resin are bonded; 2. The electrostatic charge image developing toner according to claim 1, wherein the toner for electrostatic charge image development according to claim 1 is obtained through a shell adhesion step of attaching resin fine particles to the particle surface to form core-shell adhesion particles and a coalescence step of coalescing the core-shell adhesion particles. A method for producing a toner for developing an electrostatic charge image.   Aggregation process for forming core aggregated particles in a dispersion containing fine particles of crystalline polyester resin and amorphous polyester resin, and fine particles of copolymer resin of polystyrene and (meth) acryl are adhered to the surface of the core aggregated particles. 3. An electrostatic charge image developing toner according to claim 2, wherein the electrostatic charge image developing toner according to claim 2 is obtained through a shell attachment step for forming the core-shell attachment particles and a coalescing step for combining the core-shell attachment particles. Toner manufacturing method.