JP2007058137A - Electrophotographic toner and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner for electrostatic charge image development excellent in fixability in a low temperature region and excellent also in image quality maintaining property and storage stability, and a method for manufacturing the same. <P>SOLUTION: The electrophotographic toner contains at least a binder resin A, a colorant and a release agent, further contains a dispersed crystalline material C coated with a coating resin B, and has a shape factor SF1 of 100-140, wherein the binder resin A and the coating resin B are a polyester resin, the crystalline material C is a polyester resin or a urethane compound, and a glass transition temperature of the coating resin B is higher than that of the binder resin A. The method for manufacturing the toner is also provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrophotographic toner used in electrophotography and a method for producing the same.

  A number of methods are known as electrophotographic methods. In general, an exposure process for forming an electrostatic latent image on a photoreceptor layer using a photoconductive material by using various means, a developer containing toner, and the like. Basic steps such as a step of developing an electrostatic latent image, a step of transferring toner to a recording material such as paper, a step of fixing the toner image on a recording material by heat, pressure, etc., and a step of removing toner remaining on the photoreceptor layer. It consists of processes (see, for example, Patent Documents 1 and 2).

  As the developer used here, a two-component developer composed of a toner and a carrier and a one-component developer using a magnetic toner or a nonmagnetic toner alone are known. For the production of toner, a kneading and pulverizing method is generally generally employed in which a thermoplastic resin is melt-kneaded together with a release agent such as a colorant, a charge control agent, and a wax, cooled and then finely pulverized and classified. In these toners, inorganic or organic fine particles may be added to the surface of the toner particles in order to improve fluidity and cleaning properties as necessary. Although the addition of these fine particles can produce an excellent toner, there are several problems as follows.

  In ordinary kneading and pulverizing methods, the shape and surface structure of the toner are indefinite, and they vary slightly depending on the pulverization properties of the materials used and the conditions of the pulverization process, so it is not possible to control the shape and surface structure of the toner. It was difficult. In the kneading and pulverizing method, the range of material selection is limited. Specifically, the melt-kneaded product before pulverization must be sufficiently brittle and easily pulverized by an economically possible production apparatus. However, if the melt-kneaded material is made brittle in order to satisfy the requirement, the toner may further generate fine powder or change in toner shape due to mechanical shearing force applied to the toner in the developing machine. Due to these effects, in the two-component developer, the fine powder adheres to the surface of the carrier and accelerates the charging deterioration of the developer, and in the one-component developer, the particle size distribution expands to cause toner scattering, or the toner shape changes. This causes a problem that the developability is lowered and the image quality is deteriorated.

  Further, even when a large amount of a release agent such as wax is internally added to the toner by the kneading and pulverization method, depending on the combination with the thermoplastic resin, the exposure of the release agent to the toner surface is often suppressed. . In particular, in the case of a combination of a resin whose elasticity is increased by the high molecular weight component added to the toner and is slightly pulverized and a brittle wax such as polyethylene, polyethylene is often exposed on the toner surface. This is advantageous for releasability during fixing and cleaning of untransferred toner from the photoreceptor, but the polyethylene on the toner surface layer is easily transferred to the surface of the developing roll, photoreceptor, carrier, etc. by mechanical force. Will contaminate them and reduce their reliability.

  Furthermore, since the toner shape is irregular, sufficient fluidity may not be ensured even if a flow aid is added, and the fine particles on the toner surface move to the toner recess due to the mechanical shearing force in the machine. Over time, the fluidity of the toner is lowered, or the fluidity aid is buried in the toner, so that developability, transferability, and cleaning properties are deteriorated. Further, when the toner collected in the cleaning process is returned to the developing machine and used again, the image quality is further deteriorated. In order to prevent these problems, if the flow aid is further increased, black spots are generated on the photoreceptor or the flow aid particles are scattered.

  On the other hand, in the electrophotographic process, the characteristics required for toners are increasing more and more for long life, miniaturization, high speed, and colorization. In particular, various attempts have been made to lower the fixing temperature of toner as a technique corresponding to speeding up, downsizing, and energy saving of a fixing device. However, compatibility with the storage stability of the toner is important, and a technique using a crystalline polymer has been proposed for this problem. However, when a crystalline polymer is used, pulverization is difficult and it is difficult to produce a toner having a small particle diameter.

  For this reason, a toner production method using various polymerization methods different from the kneading and pulverization method has been studied. For example, a toner production method using a suspension polymerization method has been proposed (see, for example, Patent Documents 3 and 4). However, when toner is produced using these methods, even if it is attempted to control the particle size distribution of the toner, it is not possible to leave the range of the kneading and pulverization method, and in many cases, further classification operation is required. Further, since the toner obtained by these methods has a substantially spherical shape, there is a problem that the toner remaining on the photosensitive member or the like is very poorly cleaned and the image quality reliability is impaired.

  Furthermore, in recent years, as a method for positively controlling the toner shape and the surface structure, a toner production method using an emulsion polymerization aggregation method has been proposed (see, for example, Patent Documents 5 and 6). In these methods, a resin dispersion is prepared by an emulsion polymerization method, and a colorant dispersion in which a colorant is dispersed in a solvent is prepared, and these are mixed to form an aggregate corresponding to the toner particle size, and heated. This is a method for producing a toner that is fused and united with each other. By this method, the shape can be controlled to some extent, and the chargeability and durability can be improved.

As a combination of this emulsion polymerization aggregation method and a crystalline substance, there has been proposed a toner obtained by fusing resin fine particles containing a crystalline substance and an amorphous polymer in an aqueous medium (for example, patents). Reference 7). This proposal makes it possible to lower the fixing temperature. However, this proposal has a drawback that the storage stability at high temperatures is inferior because the crystalline substance and the binder resin are partially compatible before fixing. In addition, since a large amount of crystalline substance exists near the toner surface, there is a disadvantage that the crystalline substance is exposed on the toner surface in the developing unit when used for a long time, and the image quality is adversely affected.
US Pat. No. 2,297,691 Japanese Patent Publication No.42-23910 JP-A-62-73276 JP-A-5-027476 Japanese Patent Laid-Open No. 63-282275 JP-A-6-250439 Japanese Laid-Open Patent Publication No. 2001-42568

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide an electrostatic charge developing toner excellent in fixability in a low temperature range and excellent in image quality maintenance and storage and a method for producing the same.

As a result of intensive studies, the present inventors have found that the following present invention solves the above-mentioned problems and have completed the present invention.
That is, the present invention
<1> An electrophotographic toner having a shape factor SF1 of 100 to 140, containing a binder resin A, a colorant, and a release agent, and further dispersing a crystalline substance C coated with a coating resin B. The binder resin A, the coating resin B and the crystalline substance C are polyester resins, and the glass transition temperature of the coating resin B is higher than the glass transition temperature of the binder resin A. Toner.

<2> An electrophotographic toner having a shape factor SF1 of 100 to 140, containing a binder resin A, a colorant and a release agent, and further dispersing a crystalline substance C coated with a coating resin B. The binder resin A and the coating resin B are polyester resins, the crystalline substance C is a urethane compound, and the glass transition temperature of the coating resin B is higher than the glass transition temperature of the binder resin A. This is an electrophotographic toner.

<3> The electrophotographic toner according to <1> or <2>, wherein the crystalline substance C has a melting point lower than that of the release agent.

<4> The method for producing an electrophotographic toner according to any one of <1> to <3>, wherein the coating resin B and the crystalline substance C are dissolved in an organic solvent and dispersed in water. The crystalline resin fine particle dispersion is prepared by removing the organic solvent to prepare a crystalline resin fine particle dispersion in which the crystalline resin C is coated with the coating resin B and dispersed with crystalline resin fine particles having an average particle diameter of 1 μm or less. A preparation step, the crystalline resin fine particle dispersion, a binder resin fine particle dispersion in which fine particles of a binder resin A having an average particle size of 1 μm or less are dispersed, a release agent fine particle dispersion in which release agent fine particles are dispersed, and Aggregated particles that form agglomerated particles by mixing a colorant particle dispersion in which colorant particles are dispersed and aggregating particles including crystalline resin fine particles, binder resin fine particles A, colorant particles, and release agent particles Forming step, and the glass transition of the binder resin A to the aggregated particles Is a manufacturing method of the electrophotographic toner, comprising a, a coalescence process of coalescence by heating the degrees of temperature.

<5> The method for producing an electrophotographic toner according to <4>, wherein the crystalline resin fine particles have an average particle size of 50 to 1000 nm.

  The present invention can provide an electrostatic charge developing toner excellent in fixability in a low temperature region and excellent in image quality maintenance and storage, and a method for producing the same.

<Toner for electrophotography>
The toner for electrophotography of the first invention (hereinafter sometimes referred to as “the toner of the first invention”) contains a binder resin A, a colorant, and a release agent. An electrophotographic toner having a coated crystalline substance C dispersed therein and having a shape factor SF1 of 100 to 140, wherein the binder resin A, the coating resin B, and the crystalline substance C are polyester resins, The glass transition temperature of the coating resin B is higher than the glass transition temperature of the binder resin A.
The toner for electrophotography of the second invention (hereinafter sometimes referred to as “the toner of the second invention”) contains a binder resin A, a colorant and a release agent, and further a coating resin. An electrophotographic toner having a shape factor SF1 of 100 to 140 in which a crystalline substance C coated with B is dispersed, wherein the binder resin A and the coating resin B are polyester resins, and the crystal The active substance C is a urethane compound, and the glass transition temperature of the coating resin B is higher than the glass transition temperature of the binder resin A.
In the present invention, the glass transition temperature can be measured by the input compensation differential scanning calorimetry described in JIS K-7121: 87.

First, the crystalline substance C will be described.
Here, “crystallinity” refers to one having a clear endothermic peak rather than a stepwise endothermic amount change in differential scanning calorimetry (DSC). Specifically, the half-value width of the endothermic peak is It is necessary that the temperature is 15 ° C. or lower, and it is preferable that the temperature is 10 ° C. or lower. As a result, the toner can have physical properties such that the viscosity changes sharply with respect to a change in temperature.

The crystalline substance C used in the toner of the first invention is a crystalline polyester resin (hereinafter sometimes referred to as “crystalline polyester resin according to the invention”).
In the present invention, in a polymer obtained by copolymerizing other components with a crystalline polyester main chain, when the other components are 50% by mass or less, the copolymer also has the above-described thermal characteristics (in DSC). When the half-value width of the endothermic peak is 15 ° C. or less), it is classified as “crystalline” as defined in the present invention.

The melting point of the crystalline polyester resin according to the present invention is preferably in the range of 50 to 100 ° C, more preferably in the range of 55 to 95 ° C, and still more preferably in the range of 60 to 90 ° C. When the melting point of the crystalline polyester resin according to the present invention 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. If the melting point is higher than 100 ° C., low-temperature fixing may be difficult.
In the present invention, the melting point of the crystalline substance C is measured using a differential scanning calorimeter (DSC) and measured according to JIS K- when the temperature is measured from room temperature to 150 ° C. at a heating rate of 10 ° C. per minute. The melting peak temperature of the input compensation differential scanning calorimetry shown in 7121 can be obtained. However, the crystalline resin may show a plurality of melting peaks, but in the present invention, the temperature showing the maximum peak is regarded as the melting point.

In the crystalline polyester resin according to the present invention, the ester concentration M represented by the following formula (1) is preferably 0.05 or more and 0.11 or less.
Formula (1) M = K / A
In the formula (1), M represents the ester concentration, K represents the number of ester groups (average number per molecule) contained in the crystalline polyester resin, and A represents the polymer chain of the crystalline polyester resin. The number of constituent atoms (average number per molecule) is represented.
Here, the “ester concentration M” is one index indicating the content of ester groups in the polymer of the crystalline polyester resin. The “number of ester groups contained in the crystalline polyester resin” represented by K in the formula (1) refers to the number of ester bonds contained in the entire crystalline polyester resin.

  The “number of atoms constituting the polymer chain contained in the crystalline polyester resin” represented by A in the formula (1) is the total number of atoms constituting the polymer chain of the crystalline polyester resin, and is an ester bond. It includes all the atoms involved in, but does not include the number of atoms in the branched portion in other constituent sites. That is, carbon atoms and oxygen atoms derived from carboxyl groups and alcohol groups involved in ester bonds (two oxygen atoms in one ester bond) and the six carbons constituting the polymer chain, for example, in the aromatic ring, Although included in the calculation of the number of atoms, for example, a hydrogen atom in an aromatic ring or an alkyl group, or an atom or atomic group of a substituent thereof constituting the polymer chain is not included in the calculation of the number of atoms.

  Explaining with specific examples, among the total of 10 atoms of 6 carbon atoms and 4 hydrogen atoms in the arylene group constituting the polymer chain, “the polymer chain included in the crystalline polyester resin is configured. The number of atoms to be included is only 6 carbon atoms, and even if the hydrogen is substituted with any substituent, the atoms constituting the substituent are not included in the “crystalline polyester resin”. It is not included in the “number of atoms constituting the included polymer chain”.

The crystalline polyester resin has one repeating unit (for example, when the polymer is represented by H— [OCOR ¹ COOR ² O—] _n —H, the one repeating unit is represented in []. ¹ and R ² represent a monovalent group, and n represents an integer of 1 or more.) In the case of a homopolymer consisting of only two ester bonds in one repeating unit (ie, Since the number of ester groups K ′ = 2) in the repeating unit, the ester concentration M can be obtained by the following formula (1-1).
Formula (1-1) M = 2 / A ′
In the above formula (1-1), M represents the ester concentration, and A ′ represents the number of atoms constituting the polymer chain in one repeating unit.

When the crystalline polyester resin according to the present invention is a copolymer composed of a plurality of copolymer units, the number of ester groups KX and the number of atoms AX constituting the polymer chain are obtained for each copolymer unit. Can be obtained by multiplying each by the copolymerization ratio and substituting them into the formula (1). For example, a compound [(Xa) a (Xb) b (Xc)] having three copolymerized units of Xa, Xb and Xc and a copolymerization ratio of a: b: c (where a + b + c = 1) The ester concentration M for c] can be determined by the following equation (1-2).
Formula (1-2) M = {KXa × a + KXb × b + KXc × c} /
{AXa × a + AXb × b + AXc × c}
In the formula (1-2), M represents the ester concentration, KXa represents the copolymer unit Xa, KXb represents the copolymer unit Xb, KXc represents the number of ester groups in the copolymer unit Xc, and AXa represents the copolymer. Units Xa and AXb represent copolymer units Xb and AXc represent the number of atoms constituting each polymer chain in copolymer unit Xc.

  The ester concentration M of the crystalline polyester resin according to the present invention has a great influence on the chargeability of a toner prepared using the ester concentration M. This is because the resin resistance is changed due to the ester concentration M, and when the ester concentration M is increased, the resin resistance is lowered and the chargeability may be lowered. In the crystalline polyester resin according to the present invention, the ester concentration is preferably in the range of 0.05 to 0.11. In this case, sufficient chargeability and charge stability can be obtained, and a toner can be easily produced stably.

  When the ester concentration M is less than 0.05, the melting point of the crystalline polyester resin becomes high, and the adhesion to the surface of a recording medium such as paper may be lowered. Even if a sulfonic acid component is contained as a structural unit of the crystalline polyester resin, it may be difficult to stably produce a toner because of strong hydrophobicity and reduced solubility in a solvent. is there. Furthermore, since the monomer used for the synthesis of the crystalline polyester resin is also expensive, it may not be preferable in terms of cost. In addition, as a minimum of ester concentration, 0.055 is more preferable and 0.06 is still more preferable. On the other hand, if the ester concentration exceeds 0.11, the resin resistance may decrease and the chargeability of the toner may decrease. In addition, since the melting point becomes too low, the stability of the powder and the fixed image may be lowered. In addition, as an upper limit of ester concentration, 0.105 is more preferable and 0.102 is still more preferable.

As described above, the crystalline polyester resin according to the present invention is a crystalline polyester resin having an ester concentration M defined by the above formula (1) in the range of 0.05 to 0.11 (hereinafter simply referred to as “specific”). It is preferable to use “polyester resin” as a main component.
Here, the “main component” refers to a main component among the components constituting the crystalline resin and the amorphous resin used as the binder resin, and specifically, 50% by mass or more of the binder resin. Means constituents. However, in this invention, it is more preferable that specific polyester resin is 70 mass% or more among the said binder resins, and it is still more preferable that it is 80 mass% or more.

  The crystalline polyester resin according to the present invention is synthesized from an acid (dicarboxylic acid) component and an alcohol (diol) component. In the present invention, the “acid-derived component” is a polyester resin, a polyester resin. The component part which was an acid component before the synthesis | combination of (1) is pointed out, and the "alcohol-derived component" means the component part which was an alcohol component before the synthesis of the polyester resin.

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

  Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, etc. Among them, terephthalic acid is an easily available, low melting point polymer. It is preferable in terms of easy formation.

The acid-derived constituent component preferably includes a dicarboxylic acid-derived component having a sulfonic acid group in addition to the above-mentioned aliphatic dicarboxylic acid-derived constituent component and aromatic dicarboxylic acid-derived component. When a crystalline resin is used as the main component of the binder resin, it is difficult to produce toner by a conventional pulverization method. However, when the toner of the present invention is prepared by a wet manufacturing method, it can be dissolved in a solvent and water by using a crystalline resin used for the preparation of a toner containing a dicarboxylic acid-derived component having a sulfonic acid group. Thus, wet granulation can be remarkably improved.
In addition, it becomes possible to perform granulation without reducing or using the amount of the surfactant used when preparing the toner of the present invention by utilizing a wet manufacturing method as described later, so that a subsequent washing step is performed. It can be simplified. Further, since the intermolecular cohesive force is improved, it is effective for offset resistance. In addition, it is effective in that the colorant such as pigment can be well dispersed in the crystalline resin constituting the matrix of the core layer.

  Examples of such a 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 is preferable in terms of cost.

The content of the dicarboxylic acid-derived component having a sulfonic acid group in the total acid-derived constituent component is 0.1 to 6.0 constituent mol%, and more preferably 0.5 to 5.0 constituent mol%.
If the content exceeds 6.0 component mol%, the crystallinity of the synthesized polyester resin is lowered, the melting point is lowered, the image storage stability is deteriorated, and the mechanical strength of the toner is lowered. May end up. In addition, since the resin resistance is reduced and moisture is easily adsorbed, the charge amount, particularly the charge amount under high humidity, may be excessively reduced. When the content is less than 0.1 mol%, particularly when the ester concentration is low, the solubility in a solvent or water is deteriorated, the productivity is remarkably deteriorated, or the dispersibility of the pigment is deteriorated. There is.

  In addition to the acid-derived constituent component, a constituent component such as a dicarboxylic acid-derived constituent component having a double bond may be included. The component derived from a dicarboxylic acid having a double bond includes a component derived from a lower alkyl ester or acid anhydride of a dicarboxylic acid having a double bond.

The dicarboxylic acid having a double bond can be suitably used to prevent hot offset at the time of fixing since the entire resin can be crosslinked using the double bond. Examples of such dicarboxylic acids include, but are not limited to, fumaric acid, maleic acid, 3-hexenedioic acid, and 3-octenedioic acid. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned. Among these, fumaric acid, maleic acid and the like are preferable in terms of cost.
When these dicarboxylic acid-derived constituent components having a double bond are contained, the content in the total acid-derived constituent components is preferably 20 constituent mol% or less, and more preferably 10 constituent mol% or less. When the content exceeds 20 component mol%, the crystallinity of the polyester resin is lowered, the melting point is lowered, the image storage stability is deteriorated, and the mechanical strength of the toner is lowered.
In the present invention, “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 component, it is desirable to use an aliphatic dicarboxylic acid. 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, Examples thereof include, but are not limited to, 14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol, and the like. Of these, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferable in view of availability and cost.

The alcohol-derived constituent component preferably has an aliphatic diol-derived constituent component content of 80 constituent mol% or more, and in this case, may contain other components as necessary. As the alcohol-derived constituent component, the content of the aliphatic diol-derived constituent component is preferably 90 constituent mol% or more.
When the content is less than 80 mol%, the crystallinity of the polyester resin is lowered and the melting point is lowered, so that toner blocking resistance, image storage stability, and low-temperature fixability may be deteriorated. Moreover, as other components contained as needed, constituent components such as a diol-derived constituent component having a double bond can be mentioned.

Examples of the diol having a double bond include 2-butene-1,4-diol, 3-butene-1,6-diol, 4-butene-1,8-diol, and the like.
When the diol-derived constituent component having a double bond is contained, the content in the alcohol-derived constituent component is preferably 20 constituent mol% or less, and more preferably 10 constituent mol% or less.
When the content exceeds 20 component mol%, the crystallinity of the polyester resin is lowered, the melting point is lowered, and the storage stability of the image may be deteriorated or the mechanical strength of the toner may be lowered.

The production method of the crystalline polyester resin according to the present invention 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. For example, direct polycondensation, transesterification method Or the like can be synthesized depending on the type of monomer used as a synthesis raw material. The molar ratio (acid component / alcohol component) when the acid component reacts with the alcohol component varies depending on the reaction conditions and the like, and cannot be generally stated, but is usually about 1/1.
The production of the crystalline polyester resin can be carried out at a polymerization temperature of 180 to 230 ° C., and the reaction is carried out while reducing the pressure in the reaction system as necessary to remove water and alcohol generated during condensation.
When the monomer is not dissolved or compatible at the reaction temperature, a solvent having a high boiling point may be added as a solubilizer and dissolved. In the polycondensation reaction, the dissolution auxiliary solvent is distilled off. In the case where a monomer having poor compatibility is present 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.

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; metals such as zinc, manganese, antimony, titanium, tin, zirconium, and germanium Compound; phosphorous acid compound; phosphoric acid compound; and amine compound.
Specifically, 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 tetraethoxy , Titanium tetrapropoxide, titanium tetraisopropoxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium tetra Butoxide, Zirconium naphthenate, Zirconyl carbonate, Zirconyl acetate, Zirconyl stearate, Zirconyl octylate, Germanium oxide, Trif Alkenyl phosphite, tris (2,4-di -t- butyl-phenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, compounds such as triphenyl amine.

  The acid value (mg number of KOH necessary for neutralizing 1 g of resin) of the obtained crystalline polyester resin is easy to ensure the granulation property of the toner particles using the emulsification dispersion method described later, The chargeability and environmental stability (chargeability stability when the temperature and humidity change) of the obtained toner are easily kept good, and the like, it is preferably 5 to 30 mgKOH / g.

The acid value of the crystalline polyester resin according to the present invention can be adjusted by controlling the carboxyl group at the end of the polyester by the blending ratio and reaction rate of the raw polycarboxylic acid and polyhydric alcohol. Or what has a carboxyl group in the principal chain of polyester is obtained by using trimellitic anhydride as a polyvalent carboxylic acid component.
In the toner of the first invention, the content of the crystalline substance C (crystalline polyester resin according to the invention) in the toner is preferably 2 to 40% by mass. If the content of the crystalline substance C is less than 2% by mass, the fixing temperature may not be sufficiently lowered, and if it exceeds 40%, the thermal storage stability of the toner may be deteriorated.

The crystalline substance C used in the toner of the second invention is a urethane compound (hereinafter sometimes referred to as “urethane compound according to the invention”).
The melting point of the urethane compound according to the present invention is preferably in the range of 50 to 100 ° C, more preferably in the range of 55 to 95 ° C, and still more preferably in the range of 60 to 90 ° C. When the melting point of the urethane compound according to the present invention 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. Further, when the melting point of the urethane compound according to the present invention is higher than 100 ° C., low temperature fixing may be difficult.

  Specifically, the urethane compound according to the present invention is a urethane compound obtained by a reaction between an alcohol and an isocyanate (the alcohol includes monoalcohols such as decyl alcohol, lauryl alcohol, stearyl alcohol, and behenyl alcohol; ethylene glycol, diethylene glycol, Ethylene glycol, polyethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, cyclohexanedimethanol, xylylene glycol, dipropylene glycol, polypropylene glycol, bisphenol A, hydrogenated bisphenol A, bisphenol A ethylene oxide, bisphenol A propylene oxide Dihydric or higher alcohols such as sorbitol, glycerin; Cole derivatives: Monoisocyanates such as phenyl isocyanate and stearyl isocyanate; 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, 1,5-naphthalene Diisocyanate, 3,3′-dimethyldiphenyl-4,4′-diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, transcyclohexane 1,4-diisocyanate, diphenyl ether diisocyanate, xylylene diisocyanate, water Added xylylene diisocyanate, 2, -Diisocyanate caproic acid, tetramethyl-m-xylylene diisocyanate, tetramethyl-p-xylylene diisocyanate, trimethylhexamethylene diisocyanate, triphenylmethane triisocyanate, tris (isocyanatophenyl) thiophosphate, isocyanate alkyl 2,6-diisocyanate Pronate, 1,6,11-undecane triisocyanate, 1,8-diisocyanate-4-isocyanate methyloctane, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, etc., and Urethane modified with monomeric polyol, adduct with trimethylolpropane, polyether polyol or polyester polyol Further, urethane prepolymers, uretidione-modified products, isocyanurate-modified products, carbodiimide-modified products, uretonimine-modified products, allophanate-modified products, and burette-modified products are also used. Two or more kinds of alcohol and isocyanate may be combined. ).

In the toner of the second invention, the content of the crystalline substance C (the urethane compound according to the invention) in the toner is preferably 2 to 40% by mass, and more preferably 3 to 20% by mass. . If the content of the crystalline substance C is less than 2% by mass, the fixing temperature may not be sufficiently lowered, and if it exceeds 40% by mass, the thermal storage stability of the toner may be deteriorated.
Moreover, 50-100 degreeC is preferable and, as for melting | fusing point of the urethane compound based on this invention, 60-90 degreeC is more preferable. When the melting point of the urethane compound according to the present invention is less than 50 ° C., blocking may easily occur. On the other hand, when the melting point of the urethane compound according to the present invention exceeds 100 ° C., low-temperature fixing may be difficult.

  The binder resin A used in the toner of the first invention and the toner of the second invention (hereinafter sometimes referred to as “the toner of the invention”) is a polyester resin and has a glass transition temperature. There is no particular limitation as long as it is lower than the glass transition temperature of the coating resin B. For example, a polyester resin obtained by condensation polymerization of an alcohol component and a carboxylic acid component (the alcohol component includes ethylene glycol, diethylene glycol, triethylene glycol, polyethylene). Glycol, propylene glycol, butanediol, pentanediol, hexanediol, nonanediol, decanediol, cyclohexanedimethanol, xylylene glycol, dipropylene glycol, polypropylene glycol, bisphenol A, hydrogenated bisphenol A, Divalent or higher alcohols and alcohol derivatives such as Sphenol A ethylene oxide, bisphenol A propylene oxide, sorbitol, glycerin etc. Maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipine Divalent or higher carboxylic acids such as acid, trimellitic acid, pyromellitic acid, cyclopentanedicarboxylic acid, succinic anhydride, trimellitic anhydride, maleic anhydride, dodecenyl succinic anhydride, carboxylic acid derivatives and carboxylic anhydrides, etc. Two or more kinds of alcohol components and carboxylic acid components may be used in combination.

  The binder resin A preferably has a glass transition temperature (TgA) of 40 to 80 ° C, and more preferably 50 to 70 ° C. Moreover, it is preferable that a weight average molecular weight is 5000-50000, and it is more preferable that it is 10000-30000.

  The coating resin B used in the toner of the present invention is a polyester resin, and is not particularly limited as long as the glass transition temperature is higher than the glass transition temperature of the binder resin A. However, the polyester is composed of the same monomer as the binder resin A. Can be used.

In the toner of the present invention, the crystalline substance C is coated with the coating resin B, and the binder resin A and the crystalline substance C are not in contact before heating and fixing. The effect of the present invention is obtained in that the crystalline substance C exudes from the coating resin B, the binder resin A and the crystalline substance C are mixed, and the fixing property in the low temperature range is excellent, and the image quality maintenance and storage stability are excellent. It is done.

The coating resin B has a glass transition temperature (TgB) lower than 90 ° C. (more preferably 60 ° C. or higher and lower than 80 ° C.), so that the crystalline substance C can be stably dispersed in the toner and low temperature fixing can be performed. It is preferable for achieving compatibility. If the TgB is 90 ° C. or higher, the fixing temperature may increase.
Further, the weight average molecular weight of the coating resin B is preferably 10,000 to 100,000.
Furthermore, the amount of the coating resin B with respect to the crystalline substance C is preferably 10% by mass to 200%. If the amount of the coating resin B with respect to the crystalline substance C is less than 10% by mass, the coating may not be sufficiently performed and the dispersion of the crystalline resin in the toner may increase. If the amount exceeds 200% by mass, the crystalline resin is fixed. Sometimes it doesn't work effectively.

  As described above, the toner of the present invention requires that the glass transition temperature (TgB) of the coating resin B is higher than the glass transition temperature (TgA) of the binder resin A. If the TgB is equal to or lower than the TgA, the storage stability of the toner is lowered. The difference (TgB−TgA) between the glass transition temperature of the coating resin B and the glass transition temperature of the binder resin A is preferably 2 to 30 ° C., more preferably 3 to 15 ° C.

  Specific examples of the release agent used in the toner of the present invention include low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene; carnauba wax, rice wax, candelilla wax, wood wax, jojoba oil, rice wax, Plant waxes such as sugar wax and palm wax; animal waxes such as beeswax; minerals such as montan wax, ozokerite, ceresin, paraffin wax, acid value paraffin wax, microcrystalline wax, petroleum wax; polyolefin wax, acid value polyolefin And synthetic waxes such as wax and Fischer-Tropsch wax; and modified products thereof. These may be used alone or in combination.

The release agent preferably contains a wax having a melting point in the range of 60 to 99 ° C, more preferably in the range of 70 to 97 ° C. If the wax does not contain 60 ° C. or higher, the storage stability of the toner is lowered, and toner aggregates increase and image quality may deteriorate. Further, if the wax of 99 ° C. or lower is not included, the hot offset temperature may be lowered.
The content of the release agent is preferably 5% or more and 20% or less with respect to the toner.

  The melting point of the release agent is measured from room temperature to 200 ° C. at a temperature rising rate of 10 ° C./min using a differential scanning calorimeter (DSC-50) manufactured by Shimadzu Corporation equipped with an automatic tangential processing system. After heating and adjusting to 200 ° C. for 10 minutes, cooling from 200 ° C. to −10 ° C. at a rate of temperature decrease of 30 ° C./minute, and pre-processing to make it to −10 ° C. for 10 minutes, then increasing 20 ° C./minute It is the maximum endothermic peak obtained from the relationship between temperature (° C.) and amount of heat (mW) by heating from −10 ° C. to 200 ° C. at a temperature rate.

  The melting point of the release agent is preferably higher than the melting point of the crystalline substance C (the melting point of the crystalline substance C is lower than the melting point of the release agent). When the melting point of the release agent is lower than the melting point of the crystalline substance C, offset may occur. The temperature difference between the melting point of the release agent and the melting point of the crystalline substance C is preferably 4 to 40 ° C, and more preferably 2 to 50 ° C.

  Examples of the colorant used in the toner of the present invention include known ones. Examples of the black pigment include carbon black such as furnace black, channel black, acetylene black, and thermal black, copper oxide, manganese dioxide, titanium oxide, Examples include aniline black, activated carbon, nonmagnetic ferrite, and magnetite.

  Examples of yellow pigments include yellow lead, zinc yellow, yellow iron oxide, cadmium yellow, chrome yellow, Hansa yellow, Hansa yellow 10G, benzidine yellow G, benzidine yellow GR, selenium yellow, quinoline yellow, and permanent yellow. NCG etc. are mentioned.

  Examples of the orange pigment include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, benzidine orange G, indanthrene brilliant orange RK, and indanthrene brilliant orange GK. Red pigments include Bengala, Cadmium Red, Red Plum, Mercury Sulfide, Watch Young Red, Permanent Red 4R, Risor Red, Brilliantamine 3B, Brilliantamine 6B, Daypon Oil Red, Pyrazolone Red, Rhodamine B Lake, Lake Red C , Rose bengal, oxin red, alizarin lake and the like.

  Blue pigments include bitumen, cobalt blue, alkali blue rake, Victoria blue rake, fast sky blue, indanthrene blue BC, aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxare. Rate and so on. Examples of purple pigments include manganese purple, fast violet B, and methyl violet lake.

Examples of the green pigment include chromium oxide, chromium green, pigment green, malachite green lake, final yellow green G and the like. Examples of white pigments include zinc white, titanium oxide, antimony white, and zinc sulfide. Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Furthermore, examples of the dye include various dyes such as basic, acidic, dispersion, and direct dyes, such as nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.
Further, these colorants can be used alone or mixed and further in a solid solution state.

  These colorants may use polar surfactants and may be used by being dispersed in an aqueous system by the homogenizer. At that time, a polar resin having an acid value of 10 to 50 mgKOH and a volume average particle diameter of 100 nm or less. Fine particles can be added in the range of 0.4 to 10% by mass, preferably 1.2 to 5.0% by mass, and the colorant can be coated for use.

  The polar resin fine particles can be coated by a known method. Specifically, colorant particles and ion-exchanged water are mixed as appropriate, a colorant particle dispersion is prepared using the above-described arbitrary disperser, and then polar resin fine particles are added and adhered thereto. Alternatively, the colorant particles and ion-exchanged water may be appropriately mixed and dispersed using the above arbitrary disperser, and then the polar resin fine particles may be added and further homogenized to adhere to the colorant particles. Absent. Furthermore, the polar resin fine particles may be added all at once to the colorant particle dispersion, or may be added stepwise, but gradually added while dropping from the viewpoint of adhesion. preferable.

  The colorant is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP permeability, and dispersibility in the toner. The addition amount of the colorant is in the range of 1 to 20% by mass with respect to 100% by mass of the resin of the toner. When a magnetic material is used as the black colorant, it is added in the range of 30 to 100% by mass, unlike other colorants.

The toner of the present invention preferably contains a toluene insoluble matter. The toluene insoluble matter is the mass% of the substance that does not dissolve in toluene in the toner. Specifically, 50 mg of toner and 40 g of toluene are mixed, stirred and mixed at 20 to 30 ° C. for 17 hours, and then 2 at 12000 rpm. Centrifugation is performed for 20 minutes, 20 g of the obtained supernatant liquid is dried to calculate the toluene-soluble content from the weight, and the toluene-insoluble content is calculated by subtracting the toluene-soluble content from 50 mg.
The toluene-insoluble content is preferably 10 to 50%, particularly preferably 20 to 40%.

  As a method for controlling the toluene insoluble content within the above range, latex crosslinking, crosslinking between latex particles with a polyvalent metal ion collector, and increase in structural viscosity by adding inorganic fine particles can be performed. In the crosslinking of the latex, the crosslinking in the particles such as latex and inorganic fine particles is weak, to suppress coalescence of the wax fine particles melted in the process of heating the toner particles, and to suppress the protrusion of the wax to the toner surface. More preferred is thickening by ionic crosslinking with a polyvalent metal ion flocculant. Moreover, these can be used in combination.

  Examples of the inorganic fine particles include silica, alumina, titania, calcium carbonate, magnesium carbonate, and tricalcium phosphate, all of which are usually used as external additives on the toner surface, such as ionic surfactants and It can be used by dispersing in a polymer acid or a polymer base. In order to improve the dispersibility in the toner, the surface of the inorganic fine particles is preferably hydrophobized with a silane coupling agent or the like. The amount of inorganic fine particles is preferably 10% by mass or less based on the toner.

The shape of the toner of the present invention is
Shape factor SF1 = (ML ² / A) × (π / 4) × 100
SF1 calculated as (where ML: absolute maximum length of toner particles, A: projected area of toner particles) is in the range of 100 to 140, preferably in the range of 100 to 135. The shape factor SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope image with an image analyzer (Luzex). Specifically, the image is obtained by taking an optical microscope screen of toner dispersed on a slide glass into a Luzex image analyzer using a video camera and obtaining an average value measured for 100 or more toners. If it is 140 or more, the toner is broken and the encapsulated crystalline resin is easily exposed, and as a result, storage stability and chargeability are lowered.

  In the toner of the present invention, the onset Tg at the first temperature rise in the DSC curve is preferably in the range of 45 to 80 ° C, and more preferably in the range of 50 to 70 ° C. When the onset Tg is 45 ° C. or higher, the occurrence of a blocking phenomenon under high temperature and high humidity can be prevented, and excellent storability can be obtained. Further, when the onset Tg is 80 ° C. or lower, the low temperature fixability is sufficiently exhibited.

  Further, the toner of the present invention shows a clear endothermic peak at the first temperature rise and the second temperature rise, and the endothermic peak at the second temperature rise is 1 / of the endothermic peak at the first temperature rise. The range is preferably 10 or more and 1/2 or less, and more preferably 1/9 or more and 1/2 / 2.5 or less. In the toner of the present invention, it is preferable that the crystalline substance C is uniformly dispersed without softening the binder resin before the fixing heating. During the fixing heating, the crystalline substance C is instantaneously melted and fixed at a low temperature. It is preferable to exhibit sufficiently. That is, if the endothermic peak at the second temperature rise is less than 1/10 of the first endothermic peak, there is a high possibility that a component that softens the binder resin is present before fixing and heating, If the endothermic peak at the second temperature rise exceeds 1/2 of the first endothermic peak, which may adversely affect the charge retention and offset resistance, the low temperature fixing may not be sufficiently exhibited.

  On the other hand, the behavior in which the endothermic peak at the second temperature rise of the toner is in the range of 1/10 to 1/2 of the endothermic peak at the first temperature rise is to obtain the charge maintaining property under high temperature and high humidity. Is preferred. In this way, a crystalline substance exhibiting sharp melting behavior in which toner particles have almost no low-melting point component is uniformly dispersed in the binder resin without softening the binder resin. The blocking phenomenon can be prevented, and the charge maintaining property under high temperature and high humidity can be obtained.

In the toner of the present invention, the crystalline substance C has a DSC curve having an endothermic peak temperature at the time of the first temperature rise and a peak temperature width at a height that is 1/8 of the height from the baseline to the peak top. It is preferably at most 0 ° C, more preferably at most 9 ° C. If the endothermic peak temperature and the peak temperature width at the height of 1/8 from the baseline to the peak top exceed 10 ° C, there will be a crystalline substance component that softens the binder resin before fixing heating. In some cases, the blocking phenomenon is likely to occur, and the effect on the charge maintaining property may be insufficient. On the other hand, when the peak temperature width is 10 ° C. or less, it means that the crystalline substance C does not contain a component that softens the binder resin,
Sufficient storage stability and low-temperature fixability as well as charge maintenance can be provided.

  The above-mentioned onset Tg, the ratio of the endothermic peak at the second temperature rise to the endothermic peak at the first temperature rise, and the measurement of the peak temperature width are the differential scanning calories of Shimadzu Corporation equipped with an automatic tangential processing system. The sample to be measured is set on a meter (DSC-50), heated from room temperature to 150 ° C. at a rate of temperature increase of 10 ° C./min, and the relationship between temperature (° C.) and calorie (mW) is obtained. The temperature was cooled to 0 ° C. at a temperature lowering rate of 1 minute, and this was again heated to 150 ° C. at a temperature rising rate of 10 ° C./minute, and data was collected. Here, it hold | maintains for 5 minutes each at 0 degreeC and 150 degreeC, and is based on ASTM-D3418-8. In addition, 5-20 mg (preferably 10 mg) of the measurement sample was precisely weighed and placed in an aluminum van, and an empty aluminum van was used as a reference.

The onset Tg is defined as the toner onset Tg at the first inflection point at the first temperature rise in the toner DSC curve.
Also, the endothermic peak temperature and the peak temperature width at the height of 1/8 of the height from the baseline to the peak top are the height of 1/8 of the height from the baseline to the maximum endothermic peak top. The temperature range was defined as the temperature and the maximum endothermic peak temperature.

  The toner of the present invention preferably has a volume average particle size of 4 to 9 μm, particularly preferably 5 to 8 μm. The volume average particle size of the toner of the present invention is preferably 4 μm or more from the viewpoint of developability, and 9 μm or less is preferable because there is no deterioration in image quality. The volume average particle diameter of the toner of the present invention can be measured using a measuring instrument (aperture diameter 100 μm) such as Coulter Counter TA-II (manufactured by Nikka Kisha Co., Ltd.), Multisizer II (manufactured by Nikka Kisha Co., Ltd.). it can.

The toner particle size distribution index GSDp of the present invention divides the measured particle size distribution, draws a cumulative distribution from the smaller diameter side for each particle size range (channel), and the cumulative particle size is 16%. The particle diameter is defined as the number average particle diameter D16P, the particle diameter at which the particle accumulation is 50% is defined as the volume average particle diameter, the particle diameter at which the particle accumulation is 84% is defined as the number product average particle diameter D84P, and GSDp = (D84P / D16P) ^0.5 , and the GSDp is preferably 1.00 or more and 1.30 or less, and more preferably 1.00 or more and 1.27 or less. When the GSDp is 1.00 or more and 1.30 or less, high cleaning quality can be maintained for a long time by stably maintaining the cleaning performance.

  The charge amount of the toner of the present invention is preferably in the range of 20 to 80 μC / g. If the amount of harmful charges is less than 20 μC / g, background stains (fogging) may be easily generated, and if it exceeds 80 μC / g, the image density may be easily decreased. The ratio of the charge amount in summer (high temperature and high humidity) and the charge amount in winter (low temperature and low humidity) of the toner of the present invention is preferably in the range of 0.5 to 1.5. A range of 3 is more preferable. If the ratio of the charge amounts is outside the range of 0.5 to 1.5, the chargeability is highly dependent on the environment and the charge stability may be lacking.

  When the toner of the present invention is used as a magnetic toner, magnetic powder may be contained in the binder resin. As such magnetic powder, a substance magnetized in a magnetic field is used. Specifically, ferromagnetic powders of simple metals such as iron, cobalt and nickel or alloys thereof, or compounds such as ferrite and magnetite can be used. In particular, in the present invention, in order to obtain the toner in the aqueous layer, it is necessary to pay attention to the water layer transferability of the magnetic material, and it is preferable to perform surface modification, for example, hydrophobization treatment.

  In the present invention, a charge control agent can be blended in order to further improve and stabilize the chargeability of the toner. As the charge control agent, metal salt of benzoic acid, metal salt of salicylic acid, metal salt of alkyl salicylic acid, metal salt of catechol, metal-containing bisazo dye, tetraphenylborate derivative, quaternary ammonium salt, alkylpyridinium salt, nigrosine compound , Aluminum, iron, chromium and other complex dyes, triphenylmethane pigments, resin-type charge control agents containing polar groups, and combinations of these can be used preferably. -Materials that are difficult to dissolve in water are better for controlling ionic strength that affects temporary stability and reducing pollution of wastewater. The addition amount of these charge control agents relative to the toner solid content is generally preferably in the range of 10% by mass or less.

<Method for producing electrophotographic toner>
In the method for producing the electrophotographic toner of the present invention described above, the coating resin B and the crystalline substance C are dissolved in an organic solvent and dispersed in water, and then the organic solvent is removed so that the crystalline substance C is obtained. Crystalline resin fine particle dispersion preparing step for preparing crystalline resin fine particle dispersion in which crystalline resin fine particles having an average particle diameter of 1 μm or less coated with coating resin B are dispersed, and the crystalline resin fine particle dispersion, Mixing binder resin fine particle dispersion in which fine particles of binder resin A having a diameter of 1 μm or less are dispersed, release agent fine particle dispersion in which release agent fine particles are dispersed, and colorant particle dispersion in which colorant particles are dispersed An agglomerated particle forming step of aggregating particles containing crystalline resin fine particles, binder resin fine particles A, colorant particles and release agent particles to form aggregated particles; Fusion and unity by heating to a temperature above the glass transition temperature And a fusion / unification process.
The average particle size of the crystalline resin fine particles is preferably 50 to 1000 nm.

  The method for obtaining the electrophotographic toner of the present invention described above is not particularly limited, but a wet production method for producing toner particles in water, such as an aggregation coalescence method, a suspension polymerization method, or a dissolution suspension method, is used as a developing device. It is preferable because the shape can be controlled so that the toner is hardly destroyed. In particular, an aggregation and coalescence method that allows easy shape control is preferable. The aggregation coalescence method is generally a resin fine particle dispersion containing an ionic surfactant prepared by emulsion polymerization or the like, mixed with a colorant particle dispersion and a release agent particle dispersion, and the ionic interface Aggregated particles having a toner diameter are formed by causing heteroaggregation with an aggregating agent having a polarity opposite to that of the activator, and then heated to a temperature equal to or higher than the glass transition point of the resin fine particles to fuse and combine the aggregated particles. Then, it is washed and dried to obtain a toner.

The crystalline resin fine particle dispersion preparing step prepares a crystalline resin fine particle dispersion in which the crystalline resin C is coated with the coating resin B and dispersed with crystalline resin fine particles having an average particle diameter of 1 μm or less. Is coated with the coating resin B, the difference between the solubility parameter of the crystalline substance C and the solubility parameter of the coating resin B is preferably 0.75 to 1.13. When the difference in solubility parameter is less than 0.75, the crystalline substance C and the coating resin B are compatible with each other so that a coating layer cannot be formed. When the difference is greater than 1.13, the coating layer cannot be formed easily. There is.
The solubility parameter is a numerical value representing the magnitude of the cohesive energy of the substance, and is a method proposed by Fedors [Polym. Eng. Sci. , Vol14, p147 (1974)], where the evaporation energy and molar volume of the atom or atomic group are Δei and Δvi, respectively, the solubility parameter (SP value) δ of the binder resin in the present invention can be obtained by the following equation: .
δ = (ΣΔei / ΣΔvi) ^1/2

  The crystalline resin fine particles have an average particle size of 1 μm or less, preferably 50 to 1000 nm. When the average particle diameter of the crystalline resin fine particles exceeds 1 μm, aggregated particles that become a toner may not be formed.

  On the other hand, the binder resin A has an average particle size of 1 μm or less (preferably 50 to 500 nm). When the average particle diameter of the binder resin A exceeds 1 μm, aggregated particles that become a toner may not be formed.

  In the initial stage of mixing the crystalline resin fine particle dispersion, the binder resin fine particle dispersion, the colorant particle dispersion, and the release agent particle dispersion in the aggregated particle forming step, the ionic dispersion of each polarity is previously performed. The balance of the amount of the agent is shifted, and a polymer of an inorganic metal salt such as polyaluminum chloride is added for ionic neutralization, and then the first stage is performed at a temperature below the glass transition point of the binder resin. After forming and stabilizing the mother aggregated particles, a resin fine particle dispersion treated with an ionic dispersant having a polarity and an amount that compensates for the deviation in ionic balance is added as a second step, and further if necessary. A second heating step is performed by slightly heating the resin fine particles in the aggregated particles and the resin contained in the additional resin fine particles below the glass transition point and stabilizing them at a higher temperature, followed by heating above the glass transition point. Step In particles may be those were coalesced while it is attached to the surface of the mother aggregated particles (coalescence step) was added. Further, the stepwise operation of aggregation may be repeated a plurality of times. Further, the additional fine particles may be made of a material different from the fine particles at the time of aggregation. This two-stage method is effective in improving the inclusion of the release agent, crystalline resin, and colorant.

  When a vinyl monomer is used, a resin fine particle dispersion can be prepared by carrying out emulsion polymerization using an ionic surfactant or the like. In addition, in the case of other resins, if the resin is soluble in an oily solvent with relatively low solubility in water, the resin is dissolved in those solvents and a homogenizer together with an ionic surfactant or polymer electrolyte in water. The resin fine particle dispersion can be prepared by dispersing as fine particles in water using a disperser and then evaporating the solvent by heating or decompressing.

  The release agent to be used is preferably particles having an average particle diameter in the range of 150 to 1500 nm, and is dispersed in the electrostatic charge developing toner and contained in the range of 5 to 25% by mass, whereby an oilless fixing method. It is possible to improve the peelability of the fixed image at. A preferable range of the average particle diameter of the release agent is 160 to 1400 nm, and a preferable range of the content of the release agent is 7 to 23% by mass.

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 subjected to strong shearing using a homogenizer or a pressure discharge type disperser while heating to above the melting point. It is possible to prepare a dispersion liquid of fine particles of release agent having a size of 1 μm or less.
The concentration of the surfactant used in the release agent fine particle dispersion is preferably 4% by mass or less with respect to the release agent. When it exceeds 4 mass%, the aggregation rate of particle formation becomes slow, the heating time becomes long, and the aggregate may increase.

The colorant to be used is dispersed in the toner for electrostatic charge development as particles having an average particle diameter in the range of 100 to 330 nm and contained in the range of 4 to 15% by mass, so that not only coloring property but also OHP transmission. The property is also excellent. A preferable average particle diameter is in a range of 120 to 310 nm, and a preferable content is in a range of 5 to 14% by mass.
These colorants are dispersed by a known method. For example, a rotary shearing homogenizer, a ball mill, a sand mill, an attritor, a coball mill or other media type disperser, a three roll mill or other roll mill, a nanomizer or other cavitation mill, a colloid A mill, a high-pressure opposed collision type disperser, or the like is preferably used.

  In the method for producing a toner of the present invention, a surfactant used for the purpose of emulsion polymerization of resin fine particles, dispersion of a colorant, addition dispersion of resin fine particles, dispersion of a release agent, aggregation thereof, or stabilization thereof is used. For example, it is possible to use anionic surfactants such as sulfate ester type, sulfonate type, phosphate ester type and soap type, and cationic surfactants such as amine salt type and quaternary ammonium salt type. it can. It is also effective to use a nonionic surfactant such as polyethylene glycol, alkylphenol ethylene oxide adduct, and polyhydric alcohol. As these dispersing means, general means such as a rotary shear type homogenizer, a ball mill having a medium, a sand mill, a dyno mill and the like can be used.

  In the present invention, when colorant particles coated with polar resin fine particles are used, the resin and colorant are dissolved and dispersed in a solvent (water, surfactant, alcohol, etc.), and then the appropriate dispersant as described above. (Including active agent) Dispersed in water, heated and decompressed to remove the solvent, or colored by the surface of resin fine particles prepared by emulsion polymerization with mechanical shearing force or electrical adsorption force A method of immobilizing agent particles can be employed. These methods are effective in suppressing the liberation of the colorant added to the aggregated particles and improving the dependency of the chargeable colorant.

  In the present invention, a desired toner can be obtained through any washing step, solid-liquid separation step, and drying step after completion of the fusion and coalescence step, but the washing step expresses and maintains chargeability. It is preferable to sufficiently perform substitution washing with ion-exchanged water. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration, centrifugal filtration, decanter and the like are preferably used from the viewpoint of productivity. Further, the drying process is not particularly limited, but from the viewpoint of productivity, aeration drying apparatus, spray drying apparatus, rotary drying apparatus, air flow drying apparatus, fluidized bed drying apparatus, heat transfer heating type drying apparatus, freeze drying apparatus, etc. are preferably used. It is done.

  In addition, for the purpose of imparting fluidity and improving cleaning properties, as in normal toner production, metal salts such as calcium carbonate, silica, alumina, titania, barium titanate, strontium titanate, calcium titanate, cerium oxide, Add inorganic fine particles such as metal oxide compounds such as zirconium oxide and magnesium oxide, ceramics, carbon black, etc., and resin fine particles such as vinyl resin, polyester, and silicone to the toner surface in a dry state by applying a shearing force. be able to.

  These inorganic fine particles are preferably surface-treated with a coupling material or the like in order to control conductivity, chargeability, and the like. Specific examples of the coupling material include methyltrichlorosilane, methyldichlorosilane, dimethyldichlorosilane, and trimethyl. Chlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane , Diphenyldiethoxysilane, isobutyltrimethoxysilane, decyltrimethoxysilane, hexamethylsilazane, N, N- (bistrimethylsilyl) acetamide, N, N Bis (trimethylsilyl) urea, tert-butyldimethylchlorosilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, β- (3.4 epoxycyclohexyl) ethyltrimethoxysilane, γ Silane coupling agents such as glycidoxypropyl trimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, titanium coupling agents, etc. Can give.

  As the method for adding the fine particles, the toner may be dried and then adhered to the toner surface by using a blender such as a V blender or a Henschel mixer, or the fine particles may be water-based such as water or water / alcohol. After being dispersed in a liquid, it may be added to the toner in a slurry state and dried to allow an external additive to adhere to the toner surface. Moreover, you may dry, spraying a slurry on dry powder.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these. The toner of the present invention was produced by the following method. Specifically, the following resin fine particle dispersions (crystalline resin fine particle dispersion and binder resin fine particle dispersion), colorant particle dispersion, and release agent particle dispersion were prepared, and a predetermined amount was mixed and stirred. Then, an inorganic metal salt polymer was added and ionized to neutralize to form aggregates of the particles. After adjusting the pH of the system from weakly acidic to neutral with an inorganic hydroxide, it was heated to a temperature equal to or higher than the glass transition point of the resin fine particles, and fused and united. Thereafter, a desired toner was obtained through sufficient washing, solid-liquid separation, and drying processes. Below, the specific example of the adjustment method of each material and the preparation method of an aggregated particle is shown.

(Preparation of resin fine particle dispersion 1 (binder resin A-1))
Polyester resin comprising bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid and hexanediol (Mw (weight average molecular weight, the same applies hereinafter) = 10000, Tg (glass transition temperature, the same applies hereinafter) = 60 ° C., solubility Parameter 10.1) 50 parts by mass and 450 parts by mass of ethyl acetate were mixed by heating and dissolved, and then charged into 600 parts by mass of water containing 0.3% by mass of dodecylbenzenesulfonic acid, and a rotor-stator type stirrer (Ultra Turrax: The mixture was suspended using IKA. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 160 nm and a solid content of 8% by mass.

(Preparation of resin fine particle dispersion 2 (coating resin B-1, crystalline substance C-1))
Bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, polyester resin (Mw = 50000, Tg65 ° C., solubility parameter 10.0) composed of terephthalic acid, dodecenyl succinic acid, trimellitic acid, butanediol, dodecane 2 Crystalline polyester made of acid (Mw = 20000, melting point = 71 ° C., solubility parameter 9.23) 25 parts by mass and 450 parts by mass of ethyl acetate are heated and mixed to dissolve, and then 0.3% by mass of dodecylbenzenesulfonic acid is contained. The mixture was put into 600 parts by mass of water and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 150 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion 2 was freeze-dried, stained with osmium, and observed through a transmission electron microscope (TEM). As a result, the surface layer (polyester resin) and the inside (crystalline polyester) were two layers. It was observed that the particles were separated into two.

(Preparation of resin fine particle dispersion 3 (coating resin B-1, crystalline substance C-2))
Bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, polyester resin (Mw = 50000, Tg 65 ° C., solubility parameter 10.0) composed of terephthalic acid, dodecenyl succinic acid, trimellitic acid, ethylene glycol, sebacic acid 30 parts by weight of crystalline polyester (Mw = 20000, melting point = 72 ° C., solubility parameter 9.52) and 450 parts by weight of ethyl acetate were heated and mixed to dissolve, and then water containing 0.3% by weight of dodecylbenzenesulfonic acid was dissolved. The mixture was added to 600 parts by mass and stirred using a rotor-stator stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 150 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed through a transmission electron microscope (TEM). As a result, it was separated into two layers, a surface layer (polyester resin) and an inner layer (crystalline polyester). It was observed that the particles became fine particles.

(Preparation of resin fine particle dispersion 4 (crystalline substance C-1))
After 50 parts by mass of crystalline polyester (Mw = 20000, melting point = 71 ° C., solubility parameter 9.23) and 450 parts by mass of ethyl acetate, which are composed of butanediol and dodecanedioic acid, were mixed by heating and dissolved, then 0. The mixture was put into 600 parts by mass of water containing 3% by mass and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 140 nm and a solid content of 8% by mass.

(Preparation of resin fine particle dispersion 5 (resin B-2, crystalline substance C-1))
25 parts by mass of polyester resin (Mw = 20000, Tg 55 ° C., solubility parameter 10.2) composed of bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, isophthalic acid and nonanediol, butanediol, dodecanedioic acid After dissolving 25 parts by mass of crystalline polyester (Mw = 20000, melting point = 71 ° C., solubility parameter 9.23) and 450 parts by mass of ethyl acetate with water, water containing 0.3% by mass of dodecylbenzenesulfonic acid is dissolved. The mixture was added to 600 parts by mass and stirred using a rotor-stator stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 150 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed through a transmission electron microscope (TEM). As a result, it was separated into two layers, a surface layer (polyester resin) and an inner layer (crystalline polyester). It was observed that the particles became fine particles.

(Preparation of resin fine particle dispersion 6 (resin B-3, crystalline substance C-1))
25 parts by mass of a polyester resin (Mw = 20000, Tg 63 ° C., solubility parameter 9.95) composed of bisphenol A propylene oxide adduct, terephthalic acid, isophthalic acid, and nonanediol, crystalline polyester (Mw) composed of butanediol and dodecanedioic acid = 20000, melting point = 71 ° C, solubility parameter 9.23) 25 parts by mass and 450 parts by mass of ethyl acetate were heated and mixed to dissolve, and then charged into 600 parts by mass of water containing 0.3% by mass of dodecylbenzenesulfonic acid, The mixture was suspended by stirring using a rotor stator type stirrer (Ultra Turrax: manufactured by IKA). Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 150 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed with a transmission electron microscope (TEM) to observe a uniform structure.

(Preparation of resin fine particle dispersion 7 (resin B-4, crystalline substance C-1))
Polyester resin composed of bisphenol A ethylene oxide adduct, terephthalic acid, isophthalic acid and nonanediol (Mw = 20000, Tg 74 ° C., solubility parameter 10.4), 25 parts by mass, crystalline polyester composed of butanediol and dodecanedioic acid (Mw) = 20000, melting point = 71 ° C, solubility parameter 9.23) 25 parts by mass and 450 parts by mass of ethyl acetate were heated and mixed to dissolve, and then charged into 600 parts by mass of water containing 0.3% by mass of dodecylbenzenesulfonic acid, The mixture was suspended by stirring using a rotor stator type stirrer (Ultra Turrax: manufactured by IKA). Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 150 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion was freeze-dried, stained with osmium, and the cross section of the particles was observed with a transmission electron microscope (TEM). As a result, two types of fine particles having different shades were observed.

(Preparation of resin fine particle dispersion 8 (binder resin A-1, coating resin B-1, crystalline substance C-1))
Bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, dodecenyl succinic acid, polyester resin consisting of trimellitic acid (coating resin, Mw = 50000, Tg 65 ° C., solubility parameter 10.0) 8.4 parts by mass, Polyester resin composed of bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, hexanediol (binder resin, Mw = 10000, Tg 60 ° C.) 33.2 parts by mass, crystals composed of butanediol, dodecanedioic acid 8.4 parts by weight of a reactive polyester (Mw = 20000, melting point = 71 ° C., solubility parameter 9.23) and 450 parts by weight of ethyl acetate were dissolved by heating, and then water containing 0.3% by weight of dodecylbenzenesulfonic acid 600 It was charged to the amount unit, rotor stator stirrer (Ultra-Turrax: IKA Co.) were suspended stirred mixture used. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 152 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed with a transmission electron microscope (TEM). The surface layer (coating resin) and the interior (crystalline polyester and binder resin) were observed. It was observed that the particles were separated into two layers.

(Preparation of resin fine particle dispersion 17)
Polyester resin consisting of bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, dodecenyl succinic acid, trimellitic acid, bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, isophthalic acid, nonane Weight ratio of 15:10 mixture with polyester resin comprising diol (Mw = 40000, Tg 61 ° C., solubility parameter 10.08) 25 parts by mass, crystalline polyester comprising butanediol, dodecanedioic acid (Mw = 20000, melting point = 71) C., solubility parameter 9.23) 25 parts by mass and 450 parts by mass of ethyl acetate were heated and mixed to dissolve, and then charged into 600 parts by mass of water containing 0.3% by mass of dodecylbenzenesulfonic acid, and the rotor stay The mixture was suspended using a turbulent stirrer (Ultra Turrax: manufactured by IKA). Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 150 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion 2 was freeze-dried, stained with osmium, and observed through a transmission electron microscope (TEM). As a result, the surface layer (polyester resin) and the inside (crystalline polyester) were two layers. It was observed that the particles were separated into two.

(Preparation of resin fine particle dispersion 18)
Polyester resin consisting of bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, dodecenyl succinic acid, trimellitic acid, bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, isophthalic acid, nonane Weight ratio with a polyester resin comprising diol: 10:15 mixture (Mw = 30000, Tg 59 ° C., solubility parameter 10.12) 25 parts by mass, crystalline polyester comprising butanediol, dodecanedioic acid (Mw = 20000, melting point = 71) C., solubility parameter 9.23) 25 parts by mass and 450 parts by mass of ethyl acetate were heated and mixed to dissolve, and then charged into 600 parts by mass of water containing 0.3% by mass of dodecylbenzenesulfonic acid, and the rotor stay The mixture was suspended using a turbulent stirrer (Ultra Turrax: manufactured by IKA). Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 150 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion 2 was freeze-dried, stained with osmium, and observed through a transmission electron microscope (TEM). As a result, the surface layer (polyester resin) and the inside (crystalline polyester) were two layers. It was observed that the particles were separated into two.

(Preparation of Colorant Particle Dispersion 1)
Cyan pigment (CI Pigment Blue 15: 3): 50 parts by weight anionic surfactant (Neogen SC, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., solid content 65%): 5 parts by weight ion-exchanged water: 200 parts by weight The mixture was dissolved and dispersed by ultrasonic irradiation with a homogenizer (Ultra Tarax manufactured by IKA) to obtain a colorant particle dispersion 1 having a central particle size of 167 nm and a solid content of 22% by mass.

(Preparation of Colorant Particle Dispersion 2)
Colorant particles having a center particle size of 159 nm and a solid content of 22% by mass are the same as the preparation of the colorant particle dispersion 1 except that the same amount of black pigment (carbon black: manufactured by Cabot) is used instead of the cyan pigment. Dispersion 2 was obtained.

(Preparation of release agent particle dispersion 1)
Wax having a melting point of 85 ° C .: 50 parts by mass (Polywax 500 (manufactured by Baker Petrolite)
Anionic surfactant: 2.3 parts by mass (Neogen SC, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., solid content: 65% by mass)
Ion-exchanged water: 200 parts by mass The composition was heated to 95 ° C. and sufficiently dispersed with IKA Ultra Turrax T50, and then dispersed with a pressure discharge type homogenizer, with a center particle size of 270 nm and a solid content of 21%. A release agent particle dispersion was obtained.

(Preparation of release agent particle dispersion 2)
Wax with a melting point of 75 ° C .: 50 parts by mass (HNP9 (Nippon Seiwa Co., Ltd.)
2.3 parts by weight of anionic surfactant (Neogen SC, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., solid content 65%)
Ion-exchanged water: 200 parts by mass The composition was heated to 95 ° C. and sufficiently dispersed with IKA Ultra Turrax T50, and then dispersed with a pressure discharge type homogenizer, with a central particle size of 250 nm and a solid content of 21 % Release agent particle dispersion

[Example 1]
The resin fine particle dispersion 1: 329 parts by weight The resin fine particle dispersion 2: 401 parts by weight The colorant particle dispersion 1:26 parts by weightThe release agent particle dispersion 1:62 parts by weight Polyaluminum chloride (10% aqueous solution) ): 2.1 parts by mass Ion-exchanged water: 248 parts by mass The above ingredients were thoroughly mixed and dispersed in a round stainless steel flask using IKA Ultra Turrax T50, and then the flask was heated in an oil bath for heating. Heat to 45 ° C. with stirring. After maintaining at 45 ° C. (initial heating temperature), 108 parts by mass of the resin fine particle dispersion 1 was gradually added thereto.
Then, after adjusting the pH in the system to 8.0 using an aqueous sodium hydroxide solution having a concentration of 0.5 mol / L, the stainless steel flask is sealed, and the stirring shaft seal is magnetically sealed while stirring is continued. Heated to 92 ° C. After completion of the reaction, the reaction mixture was cooled, filtered, sufficiently washed with ion exchange water, and solid-liquid separation was performed by Nutsche suction filtration. This was further redispersed with 3 L of ion exchanged water, and stirred and washed at 300 rpm for 15 minutes. This washing operation was further repeated 5 times, and No. 1 was obtained by Nutsche suction filtration. Solid-liquid separation was performed using 5A filter paper. Next, vacuum drying was continued for 12 hours to obtain toner particles.

(Evaluation methods)
To the toner particles obtained, 0.8% by mass of silica (TS720, manufactured by Cabot Corporation) was added and mixed to obtain a toner.
For the obtained toner, in the shape factor SF1, the average particle diameter, and the DSC curve, the onset Tg at the first temperature rise and the endothermic peak at the second temperature rise were divided by the endothermic peak at the first temperature rise. The endothermic peak temperature at the time of the first temperature rise and the peak temperature width at a height of 1/8 of the height from the baseline to the peak top were measured by the measurement method described above. The results are shown in Table 1.

Preservability The obtained toner was put in an oven at 50 ° C. for 24 hours, and then the presence or absence of aggregates was visually observed. The results are shown in Table 2.

  On the other hand, a carrier was prepared by coating 1% by mass of polymethyl methacrylate (manufactured by Soken Chemical Co., Ltd.) on a 50 μm ferrite core. The obtained toner and this carrier were mixed to prepare a developer by adjusting the toner concentration to 8% by mass.

・ Minimum fixing temperature A solid image was formed on the copy paper (J paper) made by Fuji Xerox so that the developer amount became 0.9 mg / cm ^2, and A-color935 (Fuji Xerox Co., Ltd.) The image was fixed with a remodeling machine, and the fixing property was evaluated. In the evaluation, the fixing device temperature was changed from 80 ° C. to 150 ° C. at every 10 ° C., and a fixed image was prepared at each fixing temperature. The degree of peeling of the image was observed, the width of the paper appearing at the crease as a result of the peeling of the image was measured, and the fixing temperature at which the width became 0.5 mm or less was defined as the minimum fixing temperature. The results are shown in Table 2.

-Image quality evaluation Using the obtained developer, the uniformity of the image was evaluated visually with respect to a fixed image after 10,000 copies were made with a modified A-color 935 manufactured by Fuji Xerox Co., Ltd. The results are shown in Table 2.

[Example 2]
In Example 1, the same procedure as in Example 1 was conducted except that the resin fine particle dispersion 2 was replaced with the same amount of the resin fine particle dispersion 3 and the colorant particle dispersion 1 was replaced with the same amount of the colorant particle dispersion 2. Toner and developer were prepared. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

[Comparative Example 1]
In Example 1, a toner and a developer were prepared in the same manner as in Example 1, except that the heating temperature 92 ° C. after adjusting the pH to 8.0 was changed to 86 ° C. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

[Comparative Example 2]
A toner and a developer were prepared in the same manner as in Example 1 except that the resin fine particle dispersion 2 was replaced with the same amount of the resin fine particle dispersion 5 in Example 1. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

[Comparative Example 3]
A toner was prepared in the same manner as in Example 1 except that the resin fine particle dispersion 2 in Example 1 was changed to the resin fine particle dispersion 6. The results are shown in Tables 1 and 2.

[Comparative Example 4]
A toner was prepared in the same manner as in Example 1 except that the resin fine particle dispersion 2 in Example 1 was changed to the resin fine particle dispersion 7. The results are shown in Tables 1 and 2.

[Comparative Example 5]
A toner and a developer were prepared in the same manner as in Example 1 except that the resin fine particle dispersion 2 was replaced with the same amount of the resin fine particle dispersion 4 in Example 1. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

[Comparative Example 6]
A toner and a developer were prepared in the same manner as in Example 1 except that the resin fine particle dispersion 2 was replaced with the same amount of the resin fine particle dispersion 8 in Example 1. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

[Example 5]
A toner and a developer were prepared in the same manner as in Example 1 except that the resin fine particle dispersion 2 was replaced with the same amount of the resin fine particle dispersion 17 in Example 1. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

[Comparative Example 15]
A toner and a developer were produced in the same manner as in Example 1 except that the resin fine particle dispersion 2 was replaced with the same amount of the resin fine particle dispersion 18 in Example 1. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

[Comparative Example 16]
In Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that the pH before heating to 92 ° C. was changed from 8.5 to 9.5. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

[Example 6]
Using the dispersion having a dispersion particle diameter of 300 nm obtained in the same manner as in the resin fine particle dispersion 2 except that 0.3% by mass of dodecylbenzenesulfonic acid was changed to 0.23% by mass, the toner and A developer was prepared. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1 and 2.

  From Tables 1 and 2, the shape factor SF1 is 100 to 140, the crystalline substance C coated with the coating resin B is dispersed, and the glass transition temperature of the coating resin B is higher than the glass transition temperature of the binder resin A. In Examples 1 and 2, it can be seen that the minimum fixing temperature is low, and the storage stability and the image quality after 10,000 sheets are good.

(Preparation of resin fine particle dispersion 9 (Resin A-2))
A polyester resin composed of bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, and hexanediol (Mw = 10000, Tg 60 ° C.) 50 parts by mass and 200 parts by mass of ethyl acetate were heated and mixed to dissolve, and then dodecylbenzene The mixture was put into 300 parts by mass of water containing 0.3% by mass of sulfonic acid and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 160 nm and a solid content of 20% by mass.

(Preparation of resin fine particle dispersion 10 (resin B-1, urethane compound-1))
Bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, polyester resin (Mw = 50000, Tg 65 ° C., solubility parameter 10.0) composed of terephthalic acid, dodecenyl succinic acid, trimellitic acid, 36.7 masses of behenyl alcohol 25 parts by weight of a urethane compound (melting point = 89 ° C., solubility parameter 9.04) obtained by reacting 1 part by weight with 13.4 parts by weight of phenyl isocyanate and 450 parts by weight of ethyl acetate were dissolved by heating, and then dodecylbenzenesulfone. The mixture was suspended in 600 parts by mass of water containing 0.3% by mass of acid, and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 200 nm and a solid content of 8% by mass. Further, the obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed through a transmission electron microscope (TEM). As a result, it was separated into two layers, a surface layer (polyester resin) and an inner layer (urethane compound). It was observed that it became fine particles.

(Preparation of resin fine particle dispersion 11 (resin B-1, urethane compound-2))
12. Bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, polyester resin (Mw = 50000, Tg 65 ° C., solubility parameter 10.0) composed of terephthalic acid, dodecenyl succinic acid, trimellitic acid, tolylene diisocyanate 12. 25 parts by mass of a urethane compound (melting point = 96 ° C., solubility parameter 9.24) obtained by reacting 2 parts by mass with 37.8 parts by mass of stearyl alcohol and 450 parts by mass of ethyl acetate were mixed by heating and dissolved, and then dodecyl The mixture was suspended in 600 parts by mass of water containing 0.3% by mass of benzenesulfonic acid and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 190 nm and a solid content of 8% by mass. Further, the obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed with a transmission electron microscope (TEM). As a result, it was separated into two layers, a surface layer (polyester resin) and an inner layer (urethane compound). It was observed that it became fine particles.

(Preparation of resin fine particle dispersion 12 (urethane compound-2))
50 parts by mass of urethane compound (melting point = 96 ° C., solubility parameter 9.24) obtained by reacting 12.2 parts by mass of tolylene diisocyanate and 37.8 parts by mass of stearyl alcohol was heated and mixed with 450 parts by mass of ethyl acetate. After dissolution, the mixture was put into 600 parts by mass of water containing 0.3% by mass of dodecylbenzenesulfonic acid, and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 190 nm and a solid content of 8% by mass.

(Preparation of resin fine particle dispersion 13 (resin B-2, urethane compound-1))
Bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, isophthalic acid, nonanediol polyester resin (Mw = 20000, Tg 55 ° C., solubility parameter 10.2) 25 parts by mass, behenyl alcohol 36.7 parts by mass 25 parts by mass of a urethane compound (melting point = 89 ° C., solubility parameter 9.04) obtained by reacting 13.4 parts by mass of phenyl isocyanate with 450 parts by mass of ethyl acetate was dissolved by heating and mixing, and then dodecylbenzenesulfonic acid The mixture was put into 600 parts by mass of water containing 0.3% by mass and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 210 nm and a solid content of 8% by mass. Further, the obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed through a transmission electron microscope (TEM). As a result, it was separated into two layers, a surface layer (polyester resin) and an inner layer (urethane compound). It was observed that it became fine particles.

(Preparation of resin fine particle dispersion 14 (resin B-5, urethane compound-1))
25 parts by mass of polyester resin (Mw = 20000, Tg 62 ° C., solubility parameter 9.79) composed of bisphenol A propylene oxide adduct, dodecanedioic acid, terephthalic acid, isophthalic acid and nonanediol, 36.7 parts by mass of behenyl alcohol and phenyl isocyanate 25 parts by mass of a urethane compound (melting point = 89 ° C., solubility parameter 9.04) obtained by reacting 13.4 parts by mass and 450 parts by mass of ethyl acetate were mixed by heating and dissolved, and then 0.3 mg of dodecylbenzenesulfonic acid The mixture was suspended in 600 parts by mass of water containing% by mass and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 200 nm and a solid content of 8% by mass. Further, the obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed with a transmission electron microscope (TEM) to observe a uniform structure.

(Preparation of resin fine particle dispersion 15 (resin B-6, urethane compound-1))
25 parts by mass of a polyester resin (Mw = 20000, Tg 74 ° C., solubility parameter 10.4) composed of bisphenol A ethylene oxide adduct, terephthalic acid, isophthalic acid, and nonanediol, 36.7 parts by mass of behenyl alcohol, and 13.4 parts by mass of phenyl isocyanate 25 parts by mass of a urethane compound (melting point = 89 ° C., solubility parameter 9.04) obtained by reacting parts and 450 parts by mass of ethyl acetate were dissolved by heating and mixed, and then 0.3% by mass of dodecylbenzenesulfonic acid was contained. The mixture was put into 600 parts by mass of water and stirred using a rotor-stator type stirrer (Ultra Turrax: manufactured by IKA) to suspend the mixed solution. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 180 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion was freeze-dried, stained with osmium, and the cross section of the particles was observed with a transmission electron microscope (TEM). As a result, two types of fine particles having different shades were observed.

(Adjustment of resin fine particle dispersion 16 (resins A, B-1, urethane compound-2))
8.4 parts by mass of bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, dodecenyl succinic acid, trimellitic acid polyester resin (Mw = 50000, Tg 65 ° C., solubility parameter 10.0), bisphenol A propylene Oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, polyester resin (Mw = 10000, Tg 60 ° C.) 33.2 parts by mass, tolylene diisocyanate 12.2 parts by mass and stearyl alcohol 37.8 parts by mass 8.4 parts by mass of a urethane compound (melting point = 96 ° C., solubility parameter 9.54) obtained by reacting and 450 parts by mass of ethyl acetate were heated and mixed to dissolve, and then 0.3% by mass of dodecylbenzenesulfonic acid The mixture was suspended using a rotor-stator stirrer (Ultra Turrax: manufactured by IKA) and suspended. Thereafter, the solvent was removed under reduced pressure. The obtained resin fine particle dispersion had a dispersed particle size of 190 nm and a solid content of 8% by mass. The obtained resin fine particle dispersion was freeze-dried, stained with osmium, and observed with a transmission electron microscope (TEM). As a result, the surface layer (coating resin) and the inside (urethane compound and binder resin) were 2 It was observed that the particles were separated into layers.

(Preparation of release agent particle dispersion 3)
Wax having a melting point of 104 ° C .: 50 parts by mass (Polywax 725 (manufactured by Baker Petrolite)
Anionic surfactant: 2.3 parts by mass (Neogen SC, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., solid content: 65%)
200 parts by mass of ion-exchanged water The above composition was heated to 95 ° C. and sufficiently dispersed with IKA Ultra Turrax T50, and then dispersed with a pressure discharge type homogenizer, with a center particle size of 270 nm and a solid content of 21%. A release agent particle dispersion 3 was obtained.

Example 3
The resin fine particle dispersion 9: 451 parts The resin fine particle dispersion 10: 281 parts The colorant particle dispersion 1: 33.4 parts The release agent particle dispersion 3: 65.9 parts polyaluminum chloride (10% aqueous solution): 2.1 parts by mass The above components were thoroughly mixed and dispersed in a round stainless steel flask using IKA Ultra Turrax T50, and then the flask was stirred with a heating oil bath. Heated to 45 ° C. After maintaining at 45 ° C. (initial heating temperature), 109 parts by mass of the resin fine particle dispersion 1 was gently added thereto.
Then, after adjusting the pH of the system to 8.0 using a 0.5 mol / L sodium hydroxide aqueous solution, the stainless steel flask was sealed, and the stirring shaft seal was magnetically sealed while stirring was continued. Heated to 92 ° C. After completion of the reaction, the reaction mixture was cooled, filtered, sufficiently washed with ion exchange water, and solid-liquid separation was performed by Nutsche suction filtration. This was further redispersed with 3 L of ion exchanged water, and stirred and washed at 300 rpm for 15 minutes. This washing operation was further repeated 5 times, and No. 1 was obtained by Nutsche suction filtration. Solid-liquid separation was performed using 5A filter paper. Next, vacuum drying was continued for 12 hours to obtain toner particles.

To the toner particles obtained, 0.8% by mass of silica (TS720, manufactured by Cabot Corporation) was added and mixed to obtain a toner. Evaluation similar to Example 1 was implemented about the obtained toner. The results are shown in Table 3 (the storage stability is shown in Table 4).
Further, a developer was prepared by the same method as in Example 1, and the same evaluation as in Example 1 was performed. The results are shown in Table 4.

Example 4
In Example 3, the same procedure was followed as in Example 3 except that the resin fine particle dispersion 10 was replaced with the same amount of the resin fine particle dispersion 11 and the colorant particle dispersion 1 was replaced with the colorant particle dispersion 2. An agent was prepared. Further, the same evaluation as in Example 3 was performed. The results are shown in Tables 3 and 4.

[Comparative Example 8]
A toner and a developer were prepared in the same manner as in Example 3, except that the resin fine particle dispersion 10 was replaced with the same amount of the resin fine particle dispersion 13 in Example 3. Further, the same evaluation as in Example 3 was performed. The results are shown in Tables 3 and 4.

Example 7
A toner and a developer were prepared in the same manner as in Example 3 except that the release agent particle dispersion 3 was replaced with the release agent particle dispersion 2 in Example 3. Further, the same evaluation as in Example 3 was performed. The results are shown in Tables 3 and 4.

[Comparative Example 10]
A toner and a developer were prepared in the same manner as in Example 3, except that the resin fine particle dispersion 10 was replaced with the same amount of the resin fine particle dispersion 14 in Example 3. Further, the same evaluation as in Example 3 was performed. The results are shown in Tables 3 and 4.

[Comparative Example 11]
A toner and a developer were prepared in the same manner as in Example 3, except that the resin fine particle dispersion 10 was replaced with the same amount of the resin fine particle dispersion 15 in Example 3. Further, the same evaluation as in Example 3 was performed. The results are shown in Tables 3 and 4.

[Comparative Example 12]
A toner and a developer were prepared in the same manner as in Example 3 except that the resin fine particle dispersion 10 was replaced with the same amount of the resin fine particle dispersion 12 in Example 3. Further, the same evaluation as in Example 3 was performed. The results are shown in Tables 3 and 4.

[Comparative Example 13]
A toner and a developer were prepared in the same manner as in Example 3, except that the resin fine particle dispersion 10 was replaced with the same amount of the resin fine particle dispersion 16 in Example 3. Further, the same evaluation as in Example 3 was performed. The results are shown in Tables 3 and 4.

  From Table 3 and Table 4, the shape factor SF1 is 100 to 140, the crystalline substance C coated with the coating resin B is dispersed, and the glass transition temperature of the coating resin B is higher than the glass transition temperature of the binder resin A. In Examples 3 and 4, it can be seen that the minimum fixing temperature is low, and the storage stability and the image quality after 10,000 sheets are good.

Claims (5)

An electrophotographic toner having a shape factor SF1 of 100 to 140, containing a binder resin A, a colorant and a releasing agent, and further dispersing a crystalline substance C coated with a coating resin B,
The toner for electrophotography, wherein the binder resin A, the coating resin B, and the crystalline substance C are polyester resins, and the glass transition temperature of the coating resin B is higher than the glass transition temperature of the binder resin A. An electrophotographic toner having a shape factor SF1 of 100 to 140, containing a binder resin A, a colorant and a releasing agent, and further dispersing a crystalline substance C coated with a coating resin B,
The binder resin A and the coating resin B are polyester resins, the crystalline substance C is a urethane compound, and the glass transition temperature of the coating resin B is higher than the glass transition temperature of the binder resin A. A characteristic toner for electrophotography.   The toner for electrophotography according to claim 1, wherein the crystalline substance C has a melting point lower than that of the release agent. A method for producing an electrophotographic toner according to any one of claims 1 to 3,
The coating resin B and the crystalline substance C are dissolved in an organic solvent and dispersed in water. Then, the organic solvent is removed, and the crystalline substance C is coated with the coating resin B and has an average particle diameter of 1 μm or less. A crystalline resin fine particle dispersion preparing step for preparing a crystalline resin fine particle dispersion in which the crystalline resin fine particles are dispersed, and a binding resin A fine particle having a mean particle diameter of 1 μm or less and a binder resin A fine particle dispersed therein. Mixing the resin particle dispersion, the release agent particle dispersion in which the release agent particles are dispersed, and the colorant particle dispersion in which the colorant particles are dispersed, the crystalline resin particles, the binder resin particles A, and the colorant are mixed. Aggregated particle forming step of aggregating particles and particles including release agent particles to form aggregated particles, and fusing and coalescing by heating the aggregated particles to a temperature equal to or higher than the glass transition temperature of the binder resin A It is characterized by having a fusion / unification process A method for producing an electrophotographic toner.   The method for producing an electrophotographic toner according to claim 4, wherein the crystalline resin fine particles have an average particle diameter of 50 to 1000 nm.