JP2007086714A - Toner for developing electrostatic image - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To give a pigment surface an acid treatment as a means to avoid deterioration of charging property which becomes problematic when a pigment dispersant having an amine value is used, as well as to improve the dispersibility of a colorant/release agent in a toner, and to provide a toner excellent in offset property, charging property and storage stability and having good color developing property and OHP transparency in order to satisfy a demand for higher performance. <P>SOLUTION: The toner is produced in an aqueous medium and comprises at least a binding resin and a colorant, wherein 50-100 wt.% of the binding resin is a polyester resin, the colorant is a pigment whose surface is given an acid treatment, and a dispersant has been added to the colorant. The acid value of the dispersant is 1-30 mg KOH/g and the amine value of the dispersant is 1-100. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image-forming toner and a developer for developing an electrostatic latent image, and in particular, has excellent chargeability, fluidity, stability, transferability, good chargeability, good image quality, and light transmittance in OHP. The present invention relates to a new and excellent image forming toner capable of forming an excellent image and a developer for developing an electrostatic latent image.

  Conventionally, in an electrophotographic apparatus, an electrostatic recording apparatus, or the like, an electric or magnetic latent image is visualized with toner. For example, in electrophotography, an electrostatic charge image (latent image) is formed on a photoreceptor, and then the latent image is developed with toner to form a toner image. The toner image is usually transferred onto a transfer material such as paper and then fixed by a method such as heating. Toner used for electrostatic image development is generally colored particles in which a binder, a colorant, a charge control agent, and other additives are contained in a binder resin. There is a suspension polymerization method. In the pulverization method, a colorant, a charge control agent, an offset preventing agent and the like are melt-mixed in a thermoplastic resin and uniformly dispersed, and the resulting composition is pulverized and classified to produce a toner.

  According to the pulverization method, a toner having some excellent characteristics can be produced, but there is a limitation in the selection of the toner material. For example, the composition obtained by melt mixing must be capable of being pulverized and classified by economically usable equipment. From this requirement, the melt-mixed composition must be made sufficiently brittle. For this reason, when the above composition is actually pulverized into particles, a wide range of particle size distribution is likely to be formed, and when attempting to obtain a copy image with good resolution and gradation, for example, a particle size of 5 μm Hereinafter, in particular, fine powder of 3 μm or less and coarse powder of 20 μm or more must be removed by classification, which has a disadvantage that the yield becomes very low. Further, in the pulverization method, it is difficult to uniformly disperse the colorant, the charge control agent, and the like in the thermoplastic resin. In addition, since the colorant added to the toner is exposed on the surface of the obtained toner, there is a problem that the toner surface is not uniformly charged, the charge distribution of the toner is expanded, and the development characteristics are deteriorated. Therefore, because of these problems, the kneading and pulverizing method cannot sufficiently meet the demand for high performance.

  In recent years, in order to overcome these problems in the pulverization method, a toner production method by a suspension polymerization method has been proposed and implemented. A technique for producing a toner for developing an electrostatic latent image by a polymerization method is known. For example, toner particles are obtained by a suspension polymerization method. However, the toner particles obtained by the suspension polymerization method are spherical and have a drawback of poor cleaning properties. Development / transfer with a low image area ratio results in a small amount of residual toner, and poor cleaning does not pose a problem. However, images with a high image area ratio such as photographic images and untransferred images formed due to poor paper feed Toner may be generated on the photoconductor as untransferred toner, and if accumulated, the image may be soiled.

  In addition, the charging roller that contacts and charges the photosensitive member is contaminated, and the original charging ability cannot be exhibited. Furthermore, since the resin is polymerized at the same time as the preparation of the toner, the materials used in conventional toners cannot be used in many cases. Even those that can be polymerized using conventional materials may not be able to adequately control the particle size due to the influence of additives such as resins and colorants. There is a problem that is small. The problem in particular is that polyester resins that have exhibited excellent fixing performance and color suitability by the conventional kneading and grinding method cannot be used basically, so that they can sufficiently cope with downsizing, high speed, colorization, etc. It is a point that cannot be done. For this reason, a method for obtaining irregularly shaped toner particles by associating resin fine particles obtained by an emulsion polymerization method is disclosed (see Patent Document 1).

  However, in the toner particles obtained by the emulsion polymerization method, a large amount of the surfactant remains not only on the surface but also inside the particles even after the water washing step, and the environmental stability of the toner charging is impaired. The amount distribution is widened, resulting in poor soiling of the obtained image. Further, the remaining surfactant contaminates the photoreceptor, the charging roller, the developing roller, etc., and the original charging ability cannot be exhibited. In addition, even in the emulsion polymerization method in which the colorant component is hardly exposed on the toner surface, the colorant easily aggregates, so that it is difficult to add and disperse the colorant uniformly in the toner. Due to the difference, there is a problem that the non-uniformity of charging occurs and the stability when used for a long time is lowered. In the case of color output, a slight deterioration in developability and transferability causes a problem in color balance and gradation. Furthermore, since the colorant in the toner is generally hydrophilic and incompatible with the resin, the transmitted light is irregularly reflected at the interface, and the transparency of OHP or the like is hindered. Therefore, if the dispersion of the colorant is poor, there is also a problem that the transparency with OHP deteriorates.

  Japanese Patent Application Laid-Open No. 2001-66827 of Patent Document 2 discloses a pigment dispersion in which a pigment and a pigment dispersant surface-treated with a fatty acid are dissolved and / or dispersed in a first organic solvent solubilizing a binder resin. A step of preparing an oily component by mixing the binder resin and the pigment dispersion in a second organic solvent solubilizing the binder resin, and suspending the oily component in an aqueous medium And a toner obtained by removing the solvent from the resulting suspension. However, fatty acids do not have amino groups that control the chargeability of the toner.

Furthermore, in particular, in color output machines, oil-less toner that eliminates the need for an oil supply device for the fixing device and adds a release agent that replaces the oil into the toner has become common sense. Further, since it cannot be atomized as much as the colorant, it is difficult to add and disperse more uniformly, and if the dispersion of the release agent is poor, there is a problem that charging property, developability, storage property and OHP permeability are inhibited.
As described above, an electrophotographic toner that can sufficiently meet the demand for high performance has not yet been obtained.

Japanese Patent No. 2537503 JP 2001-66827 A

  Accordingly, the object of the present invention is to improve the dispersibility of the colorant / release agent in the toner and to prevent the deterioration of the charging property which becomes a problem when using a pigment dispersant having an amine value. An object of the present invention is to provide a toner having an excellent offset property, chargeability and storage stability, and good color developability and OHP permeability so as to meet the demand for higher performance by subjecting the surface to acid treatment.

As a result of intensive studies, the inventors of the present invention treated the pigment surface with an acid, and used a pigment dispersant having a predetermined acid value and amine value for a toner produced by a liquid medium method, thereby producing a colorant. It has been found that the dispersibility and dispersion stability can be improved and the chargeability can be controlled, and the present invention has been completed.
That is, the said subject is solved by following (1)-(17) of this invention.
(1) “Pigment produced in an aqueous medium and comprising at least a binder resin and a colorant, wherein 50 to 100% by weight of the binder resin is a polyester resin, and the colorant is surface-treated acidic. And the colorant is a toner added with a dispersant, wherein the dispersant has an acid value of 1 to 30 mg KOH / g or less, and an amine value of 1 to 100. ";
(2) “Image forming toner according to item (1), wherein the method of producing in the aqueous medium is a dissolution suspension method”;
(3) “The method for producing in an aqueous medium is to dissolve or disperse at least an active hydrogen group-containing compound, a polymer having a site capable of reacting with an active hydrogen group, a colorant, and a release agent in an organic solvent, The solution or dispersion is dispersed in the form of droplets in an aqueous medium to form an O / W type dispersion, and the active hydrogen group-containing compound and a polymer having a site capable of reacting with active hydrogen groups are converted into O / W. The method according to (1) or (2) above, which comprises a step of removing the organic solvent after reacting in the mold dispersion or while reacting, and washing and drying. Image forming toner ";
(4) “The method for producing in the aqueous medium includes the step of adhering the resin fine particles contained in the O / W type dispersion to the surface of the toner particles of the toner ( The toner for image formation according to item 4);
(5) "Image-forming toner according to any one of items (1) to (4), wherein the dispersant is compatible with the binder resin";
(6) "The image forming toner according to any one of (1) to (5) above, wherein the dispersant has a weight average molecular weight of 2000 to 100,000";
(7) Any one of the items (1) to (6), wherein the amount of the dispersant added is 1 part by weight to 50 parts by weight with respect to 100 parts by weight of the colorant. The toner for image formation described in the above;
(8) The item (1) to (7), wherein the dispersant is contained in the toner at a ratio of 0.1 wt% to 10 wt%. Image forming toner ";
(9) “The colorant is pigment yellow PY74, yellow PY93, PY128, PY139, PY155, PY180, PY185, pigment red PR57: 1, PR122, PR146, PR184, PR185, PR238, PR269, pigment blue PB15: 3, The image forming toner according to any one of (1) to (8), wherein the toner is selected from the group consisting of PB15: 4;
(10) “Image forming toner according to any one of (1) to (9) above, which contains a release agent”;
(11) “Image forming toner according to item (10), wherein the releasing agent has a melting point of 160 ° C. or lower”;
(12) “The image forming toner according to any one of (4) to (11)”, wherein the resin fine particles have an average particle diameter of 5 to 500 nm;
(13) "The polyester resin includes a modified polyester resin capable of reacting with active hydrogen groups and a non-modified polyester resin, and a weight ratio of the modified polyester resin to the non-modified polyester resin is 5 / 95- The image forming toner according to any one of (3) to (12), wherein the toner is 75/25;
(14) “Image forming toner according to item (13), wherein the acid value of the modified polyester resin and the non-modified polyester resin is 0 to 30 mg KOH / g”;
(15) The image according to any one of (3) to (14) above, wherein the blending ratio of the colorant and the organic solvent is in the range of 5:95 to 50:50. Forming toner ";
(16) "One-component developer for developing electrostatic latent image, characterized by using the image forming toner according to any one of (3) to (15)";
(17) “A two-component developer for developing an electrostatic latent image, comprising the image forming toner according to any one of (3) to (15) and a carrier”.

  As will be well understood from the following detailed and specific description, according to the present invention, the pigment is dispersed by subjecting the pigment surface to an acid treatment and keeping the acid value and amine value of the dispersant within a certain range. The colorability of the toner and the optical transparency of the OHP are improved, the colorant dispersion stability in the colorant dispersion is excellent, the storage stability of the colorant dispersion is improved, and the efficiency of particle preparation is improved. In addition to the improvement, it is possible to avoid the deterioration of the charging property which is a harmful effect when using the pigment dispersant. Furthermore, the selectivity of the resin and the colorant is wide, and other additives such as wax are added. The pigment dispersion system can be prevented from collapsing, and at the same time, the resin and the colorant are dissolved or dispersed in an organic solvent that dissolves the toner constituent resin, and the oil phase component is dispersed in an aqueous medium to form particles. Granulating Due to the difference in affinity between the colorant and the oil phase component and between the colorant and the aqueous medium, the colorant fine particles are uniformly dispersed in the toner particles, thereby reducing the amount of colorant exposure on the toner surface and enabling shape control. Thus, an extremely excellent effect that the spheroidization of the particles is easy is exhibited.

  Therefore, the toner obtained by this production method is excellent in chargeability, fluidity, stability, and transferability. Further, by applying this toner to a developer, an image having good chargeability, good image quality, and excellent light transmission in OHP can be formed in an image forming method for forming a latent image.

  The colorant used in the present invention can control pigment dispersibility and chargeability by performing surface treatment. Surface treatment agents for colorants include natural rosins such as gum rosin, wood rosin and tall rosin, abietic acid derivatives such as abietic acid, levopimaric acid and dextropimalic acid, and metals such as calcium, sodium, potassium and magnesium salts thereof. Examples thereof include salts, rosin modified maleic acid resins, and rosin modified phenolic resins. In particular, acidic surface treatment is preferably used in order to increase the affinity with the pigment dispersant and to control the chargeability. The amount of the surface treatment agent added to the colorant is preferably from 0.1 to 100% by weight, more preferably from 0.1 to 10% by weight, based on the colorant.

  The dispersant used in the present invention can increase the affinity between the dispersant and the binder by keeping the acid value and the amine value within a certain range, and can achieve a good balance between the polar part and the non-polar part. Can take. As a result, when the dispersant used in the present invention is added, the amine sites of the dispersant are adsorbed on the acid sites on the pigment surface, and the non-amine-based sites of the dispersant are exposed on the surface, thereby improving the chargeability of the toner. It is presumed that high dispersibility with respect to the colorant, resin and solvent is exhibited while being controlled, and the dispersibility / dispersion stability of the colorant and the fluidity of the toner are improved.

  In addition, as a dispersion resin suitably used for further increasing the dispersion of the surface-treated pigment in the present invention, lime rosin varnish, polyamide resin varnish or vinyl chloride resin varnish, nitrocellulose lacquer, aminoalkyd resin, urethane resin, acrylic resin Examples thereof include resins. The amount of the dispersion resin added is preferably from 0.1 to 100% by weight, more preferably from 0.1 to 20% by weight, based on the colorant.

  That is, in the electrophotographic toner of the present invention, the dispersibility of the colorant is improved by applying an acid treatment to the pigment surface and keeping the acid value and amine value of the dispersant within a certain range. In addition, the optical transparency of OHP is improved, and the colorant can be stably dispersed for a long time even during production, so that the efficiency of particle production is improved. Furthermore, it is possible to control the chargeability, which is a harmful effect when using a dispersant.

  In particular, a colorant, an oil phase component, a colorant, and an aqueous medium can be produced by using a dispersant having an acid value and an amine value within a certain range of the present invention, a pigment whose surface is treated with an acid, and a dispersion resin. Due to the difference in affinity, the colorant fine particles are uniformly dispersed in the toner particles, and the amount of colorant exposed on the toner surface is reduced. In addition, the range of selection of the resin and the colorant is expanded, and collapse of the pigment dispersion system due to the addition of other additives such as wax can be prevented. Further, the shape can be controlled, and the particles can be easily made spherical. Therefore, the toner obtained by this production method is excellent in chargeability, fluidity, stability, and transferability. That is, by applying the toner of the present invention to an electrophotographic developer, it is possible to form an image having good chargeability, good image quality, and excellent light transmission in OHP.

  In the present invention, 50 to 100% by weight of the binder resin of the toner is a polyester resin. By setting the polyester resin in the toner binder resin to 50 to 100% by weight, the excellent fixing performance and color suitability obtained by the conventional kneading and pulverization method can be expressed, and it can sufficiently cope with high speed and colorization. be able to. Examples of the polyester resin include all polyester resins such as a modified polyester resin, a non-modified polyester resin, and a low molecular weight polyester resin, and the total of them is 50 to 100% by weight in the binder resin, more preferably 75 to 100% by weight. It is.

The toner of the present invention is a toner that is produced in an aqueous medium and contains at least a binder resin, a colorant, and a modified polyurethane dispersant. As a typical example, at least an active hydrogen group-containing compound, an active hydrogen group, and A polymer having a reactive site, a colorant, and a release agent are dissolved or dispersed in an organic solvent, and the solution or dispersion is dispersed in the form of droplets in an aqueous medium to form an O / W type dispersion. The organic solvent is removed after washing or drying after reacting the active hydrogen group-containing compound and the polymer having a site capable of reacting with the active hydrogen group in an O / W type dispersion. The image forming toner including the step of performing will be described below.

(Organic solvent)
The organic solvent in the present invention is not particularly limited as long as it is a solvent that can dissolve and / or disperse the toner composition. As a preferable thing, it is preferable that the boiling point of this solvent is less than 150 degreeC from the point of being easy to remove. Examples of the solvent include water such as toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, methyl acetate, and ethyl acetate. Insoluble organic solvents can be used alone or in combination of two or more, and further, methyl ethyl ketone, acetone, tetrahydrofuran, dioxane, dimethylformamide, methyl cellosolve, methanol, ethanol, isopropanol, etc. can be used in combination of two or more alone. it can. The amount of solvent used is usually 40 to 300 parts, preferably 60 to 140 parts, and more preferably 80 to 120 parts with respect to 100 parts of the toner composition.

(Modified polyester resin)
The polymer having a site capable of reacting with an active hydrogen group in the modified polyester resin can be used as long as it is known, and preferably has an isocyanate group, an epoxy group, a carboxylic acid, or an acid chloride group, more preferably It has an isocyanate group. Therefore, as a particularly preferable raw material resin used in the present invention, there can be mentioned a reactive polyester resin (RMPE) modified with a group capable of urea bonding.

  Examples thereof include a polyester prepolymer (A) having an isocyanate group. Examples of the prepolymer (A) include a polycondensate of a polyol (PO) and a polycarboxylic acid (PC) and a polyester having an active hydrogen group reacted with a polyisocyanate (PIC). Examples of the group containing active hydrogen in the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable.

  The modified polyester (MPE) such as urea-modified polyester formed by the above reaction is easy to adjust the molecular weight of the polymer component, and is particularly suitable for dry toners, particularly oil-less low-temperature fixing properties (removal oil application mechanism to fixing heating medium). Not a wide range of releasability and fixability). Particularly, a polyester prepolymer whose end is modified with urea can suppress adhesion to a heating medium for fixing while maintaining high fluidity and transparency in the fixing temperature range of the unmodified polyester resin itself.

  Examples of the polyol (PO) include diol (DIO) and trivalent or higher polyol (TO), and DIO alone or a mixture of DIO and a small amount of TO is preferable.

  Examples of the diol include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol, triethylene glycol, Dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol F, bisphenol S, etc.) ); Adducts of alkylene oxides (ethylene oxide, propylene oxide, butylene oxide, etc.) of the above alicyclic diols; Alkylene oxides (ethylene oxide, propylene oxide, butylene oxide, etc.) adducts.

  Among these, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use.

  Examples of the trivalent or higher polyol (TO) include 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trivalent or higher phenols (Tris) Phenol PA, phenol novolak, cresol novolak, etc.); alkylene oxide adducts of the above trivalent or higher polyphenols.

  Examples of the polycarboxylic acid (PC) include dicarboxylic acid (DIC) and trivalent or higher polycarboxylic acid (TC), and DIC alone or a mixture of DIC and a small amount of TC is preferable. Dicarboxylic acids include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, etc.) ) And the like. Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher valent polycarboxylic acid include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polycarboxylic acid, you may make it react with a polyol using the acid anhydride or lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) of the above-mentioned thing. The ratio of the polyol (PO) and the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably 1 as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. 0.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  Examples of the polyisocyanate (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; the polyisocyanates are phenol derivatives, oximes, caprolactams And a combination of two or more of these.

  The ratio of the polyisocyanate (PIC) is usually 5/1 to 1/1, preferably 4 /, as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. When the molar ratio of [NCO] is less than 1, in the case of a urea-modified polyester, the urea content in the polyester becomes low and the hot offset resistance deteriorates. The content of the polyisocyanate (PIC) component in the polyester prepolymer (A) having an isocyanate group at the terminal is usually 0.5 to 40% by weight, preferably 1 to 30% by weight, more preferably 2 to 20% by weight. %. If it is less than 0.5% by weight, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40% by weight, the low-temperature fixability deteriorates. The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average. is there. If it is less than 1 per molecule, the molecular weight of the modified polyester will be low, and the hot offset resistance will deteriorate.

  In the present invention, a urea-modified polyester that is preferably used as a toner binder (binder resin) component can be obtained by a reaction between an isocyanate group-containing polyester prepolymer (A) and amines (B), and the product is a toner. It is subjected to a crosslinking and / or elongation reaction in an aqueous medium during the production process. As amines (B), diamine (B1), triamine or higher polyamine (B2), amino alcohol (B3), amino mercaptan (B4), amino acid (B5), and amino groups of (B1) to (B5) (B6) etc. that are blocked. Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, Isophorone diamine etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine etc.) and the like.

  Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid.

  Examples of the blocked B1-B5 amino group (B6) include ketimine compounds and oxazolyzone compounds obtained from the amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) of (B1) to (B5). Can be mentioned. Among these amines (B), preferred are (B1) and a mixture of (B1) and a small amount of (B2).

  Furthermore, the molecular weight of a modified polyester such as urea-modified polyester can be adjusted using an elongation terminator. Examples of the elongation terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds). The ratio of amines (B) is the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). The ratio is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] exceeds 2 or less than 1/2, the molecular weight of a modified polyester such as urea-modified polyester (UMPE) becomes low, and the hot offset resistance deteriorates.

  In the present invention, the polyester modified with urea bonds (UMPE) may contain urethane bonds as well as urea bonds. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

As a crosslinking agent or an extender for the modified polyester used in the present invention, an active hydrogen compound capable of reacting with a reactive group such as an isocyanate group, preferably the amines (B) can be used.
The modified polyester such as urea-modified polyester (UMPE) used as a toner binder in the present invention is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the modified polyester such as urea-modified polyester is usually 10,000 or more, preferably 20,000 to 1,000,000, more preferably 30,000 to 1,000,000 after the reaction for modification. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of the modified polyester such as urea-modified polyester is not particularly limited when the unmodified polyester (PE) described later is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. . In the case of the modified polyester alone, the number average molecular weight before the modification is usually 20000 or less, preferably 1000 to 10000, more preferably 2000 to 8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color apparatus are deteriorated.

(Crosslinking agent and extender)
In the present invention, amines can be used as a crosslinking agent and / or an extender. As amines (B), diamine (B1), triamine or higher polyamine (B2), amino alcohol (B3), amino mercaptan (B4), amino acid (B5), and amino groups of (B1) to (B5) (B6) etc. that are blocked. Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, Isophorone diamine etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine etc.) and the like.

  Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. As (B6) which blocked the amino group of (B1) to (B5), ketimine compounds obtained from the amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) of (B1) to (B5), Examples include oxazoline compounds. Among these amines (B), preferred are (B1) and a mixture of (B1) and a small amount of (B2).

  Furthermore, if necessary, the molecular weight of the modified polyester after completion of the reaction can be adjusted by using a terminator for crosslinking and / or elongation. Examples of the terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those blocked (ketimine compounds).

  The ratio of amines (B) is the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). The ratio is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] is greater than 2 or less than 1/2, the molecular weight of the urea-modified polyester (i) becomes low and the hot offset resistance deteriorates.

(Non-modified polyester)
In the present invention, not only the modified polyester (A) is used alone, but also the unmodified polyester (C) having an acid value of 0.5 to 40 mgKOH / g is used together with the modified polyester (A). It is very preferable to contain as. By using (C) in combination, the low-temperature fixability and the glossiness when used in a full-color apparatus are improved. Examples of (C) include the same polycondensates of polyol (1) and polycarboxylic acid (2) as in the polyester component (A), and preferred ones are also the same as (C). (C) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, and may be modified with, for example, a urethane bond.

It is preferable that (A) and (C) are at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component (A) and (C) preferably have similar compositions. When (A) is contained, the weight ratio (A / C) of (A) to (C) is usually 5/95 to 75/25, preferably 10/90 to 25/75, more preferably 12/88. -25/75, particularly preferably 12 / 88-22 / 78. If the weight ratio of (A) is less than 5%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

  The molecular weight distribution of the unmodified polyester (C) is measured by the following method. After about 1 g of unmodified polyester (C) is precisely weighed in an Erlenmeyer flask, 10 to 20 g of THF (tetrahydrofuran) is added to obtain a THF solution having a binder concentration of 5 to 10%. The column is stabilized in a heat chamber at 40 ° C., THF is flowed through the column at this temperature as a solvent at a flow rate of 1 ml / min, and 20 μl of the THF sample solution is injected.

The molecular weight of the sample is calculated from the relationship between the retention value and the logarithmic value of a calibration curve prepared from a monodisperse polystyrene standard sample. A calibration curve is created using a polystyrene standard sample. As a monodisperse polystyrene standard sample, the thing of the range of molecular weight 2.7 * 10 < ² > -6.2 * 10 < ⁶ > by Tosoh Corporation is used, for example. A refractive index (RI) detector is used as the detector. As the column, for example, TSKgel, G1000H, G2000H, G2500H, G3000H, G4000H, G5000H, G6000H, G7000H, GMH manufactured by Tosoh Corporation are used in combination.

  The main peak molecular weight is usually 1000 to 30000, preferably 1500 to 10000, more preferably 2000 to 8000. When the amount of the component having a molecular weight of less than 1000 is increased, the heat resistant storage stability tends to deteriorate and carrier contamination occurs. Therefore, the content is preferably 5.0% by weight or less. When the component having a molecular weight of 30000 or more increases, the low-temperature fixability tends to decrease, but it is possible to suppress the decrease as much as possible by balance control. The content of components having a molecular weight of 30000 or more is 1% or more, and varies depending on the toner material, but is preferably 3 to 6%. If it is less than 1%, sufficient hot offset resistance cannot be obtained, and if it is 10% or more, the glossiness and transparency may be deteriorated.

  Mn is 2000 to 15000 and the value of Mw / Mn is preferably 5 or less. When it is 5 or more, the sharp melt property is lacking and the glossiness is impaired. Moreover, it leads to an improvement in hot offset by using a polyester resin containing 1 to 15% of THF insoluble matter. Although THF insolubles are effective for hot offset in color toners, they are negative for gloss and transparency of OHP, but are effective within 1 to 15% for widening the mold release width. There is also a case.

  The hydroxyl value of (C) is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

The acid value of (C) is usually 0-30, preferably 5-25. By having an acid value, it tends to be negatively charged. In addition, those having an acid value and a hydroxyl value exceeding these ranges are easily affected by the environment under high temperature and high humidity and low temperature and low humidity, and are liable to cause image deterioration.
The THF-insoluble matter in the toner can be adjusted by controlling the extension and / or crosslinking of the modified polyester by the acid value of the unmodified polyester.

The measurement method is shown below.
<Method for measuring THF-insoluble matter>
About 1.0 g (A) of resin or toner is weighed. To this, about 50 g of THF is added and left at 20 ° C. for 24 hours. This is first separated by centrifugation and filtered using JIS standard (P3801) type 5 C filter paper for quantification. The solvent content of this filtrate is vacuum-dried, and the residual amount (B) is measured only for the resin content.
This residual amount is the amount dissolved in THF.

The THF insoluble content (%) is obtained from the following formula.
THF insoluble matter (%) = (A−B) / A
In the case of toner, the THF insoluble component amount (W1) and the THF soluble component amount (W2) other than the resin are separately obtained by a known method, for example, a thermal loss method by the TG method, and obtained from the following formula.
THF insoluble matter (%) = (A−B−W2) / (A−W1−W2) × 100

Here, the acid value (AV) and the hydroxyl value (OHV) in the present invention are specifically determined by the following procedure.
Measuring device: Potentiometric automatic titrator DL-53 Titrator (Metler Toledo)
Electrode used: DG113-SC (manufactured by METTLER TOLEDO)
Analysis software: LabX Light Version 1.00.000
Calibration of the apparatus: Use a mixed solvent of 120 ml of toluene and 30 ml of ethanol.
Measurement temperature: 23 ° C
The measurement conditions are as follows.
Still
Speed [%] 25
Time [s] 15
EQP titration
Titrant / Sensor
Titrant CH ₃ ONa
Concentration [mol / L] 0.1
Sensor DG115
Unit of measurement mV
Predispensing to volume
Volume [mL] 1.0
Wait time [s] 0
Titrant addition Dynamic
dE (set) [mV] 8.0
dV (min) [mL] 0.03
dV (max) [mL] 0.5
Measure mode Equilibrium controlled
dE [mV] 0.5
dt [s] 1.0
t (min) [s] 2.0
t (max) [s] 20.0
Recognition
Threshold 100.0
Steepest jump only No
Range No
Tendency None
Termination
at maximum volume [mL] 10.0
at potential No
at slope No
after number EQPs Yes
n = 1
comb. termination conditions No
Evaluation
Procedure Standard
Potential 1 No
Potential 2 No
Stop for reevaluation No

(Measurement method of acid value)
In accordance with the measurement method described in JIS K0070-1992, measurement is performed under the following conditions.
Sample preparation: 0.5 g of toner (0.3 g for ethyl acetate soluble component) is added to 120 ml of toluene and dissolved by stirring for about 10 hours at room temperature (23 ° C.). Further, 30 ml of ethanol is added to prepare a sample solution.
The measurement can be calculated by the apparatus described above, and specifically, the calculation is performed as follows.
Titrate with a pre-standardized N / 10 caustic potash to alcohol solution, and determine the acid value from the consumption of the alcohol potash solution by the following calculation.
Acid value = KOH (ml) x N x 56.1 / sample weight (where N is a factor of N / 10 KOH)

(Measurement method of hydroxyl value)
Weigh accurately 0.5 g of sample into a 100 ml volumetric flask and add 5 ml of acetylating reagent correctly. Then, it is immersed in a bath at 100 ° C. ± 5 ° C. and heated. After 1-2 hours, the flask is removed from the bath, allowed to cool, water is added and shaken to decompose acetic anhydride. Furthermore, in order to complete the decomposition, the flask is again heated in a bath for 10 minutes or more and allowed to cool, and then the wall of the flask is thoroughly washed with an organic solvent. This solution is subjected to potentiometric titration with an N / 2 potassium hydroxide ethyl alcohol solution using the electrode to determine the OH value (according to JISK0070-1966).

(Toner and glass transition point of unmodified polyester)
In the present invention, a modified polyester and an unmodified polyester are included as a resin component of the toner. However, since a polymer obtained by extending and / or crosslinking the modified polyester has a high molecular weight, no clear glass transition behavior is observed. Therefore, there is no difference between the glass transition point (Tg) of the toner and the glass transition point (Tg) of the unmodified polyester, and the glass transition point (Tg) of the toner is adjusted by the glass transition point (Tg) of the unmodified polyester. The glass transition point of the toner is usually 40 to 70 ° C., preferably 45 to 55 ° C. If it is less than 40 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of the crosslinked and / or elongated polyester resin, the dry toner of the present invention tends to have good heat-resistant storage stability even when the glass transition point is low, as compared with known polyester-based toners.

Here, the glass transition point (Tg) in the present invention is specifically determined by the following procedure. Using Shimadzu TA-60WS and DSC-60 as measuring devices, the measurement was performed under the following measurement conditions.
Measurement conditions Sample container: Aluminum sample pan (with lid)
Sample amount: 5mg
Reference: Aluminum sample pan (alumina 10mg)
Atmosphere: Nitrogen (flow rate 50 ml / min)
Temperature rise (1st)
Starting temperature: 20 ° C
Temperature increase rate: 10 ° C / min
End temperature: 150 ° C
Temperature drop Holding time: None Temperature drop temperature: 10 ° C / min
End temperature: 20 ° C
Temperature rise (2nd)
Holding time: None Temperature increase rate: 10 ° C / min
End temperature: 150 ° C
The measurement results were analyzed using the data analysis software (TA-60, version 1.52) manufactured by Shimadzu Corporation. The analysis method specifies a range of ± 5 ° C centering on the point showing the maximum peak on the lowest temperature side of the DrDSC curve which is the DSC differential curve of the second temperature rise, and the peak temperature is determined using the peak analysis function of the analysis software. Ask. Next, the maximum endothermic temperature of the DSC curve is determined using the peak analysis function of the analysis software in the range of the peak temperature + 5 ° C. and −5 ° C. in the DSC curve. The temperature shown here corresponds to the Tg of the toner.

(Coloring agent)
As the colorant of the present invention, known dyes can be used, and pigments can be preferably used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL , Isoindolinone yellow, bengara, red lead, red lead, cadmium red, cadmium mercury red, antimony red, permanent red 4R, para red, phise red, parachlor ortho nitroaniline red, risor fast scarlet G, Reliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon , Oil red, quinacridone red, pyrazolone red, polyazo red, chrome vermilion, benzidine Range, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo , Ultramarine, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridiane, emerald green, pigment green B, naphthol green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalocyanine Green, Anthraquinone Green, Oxidized Chi Tan, zinc white, lithopone and mixtures thereof can be used. Pigment yellow PY74, yellow PY93, PY128, PY139, PY155, PY180, PY185, pigment red PR57: 1, PR122, PR146, PR184, PR185, PR238, PR269, pigment blue PB15: 3, PB15: 4. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  An example of the acid treatment of the colorant used in the present invention is rosin treatment. This rosin treatment is usually performed by coupling a diazonium salt of 2-amino-5-methyl-benzenesulfonic acid and 2-hydroxy-3-naphthoic acid in a coupler solution containing 2-hydroxy-3-naphthoic acid. A rosin alkali salt solution is added to the dye, and then a lake metal salt such as calcium chloride is added to precipitate the rosin as an insoluble rosin lake metal salt on the surface of the pigment produced from the dye. It is a method to do.

  An example of the pigment surface treatment method is sulfonation. If a solvent that is insoluble or sparingly soluble in the pigment is selected without causing the dispersion solvent in the reaction system to react with the sulfonation reagent, a sulfonation reaction that can be carried out by a normal organic reaction can be used. As the sulfonating agent, sulfuric acid, fuming sulfuric acid, sulfur trioxide, chlorosulfuric acid, fluorosulfuric acid, amidosulfuric acid and the like are used. In addition, if sulfur trioxide itself is too reactive and inappropriate, or the presence of a strong acid is not preferred, sulfonation can be performed using a complex of sulfur trioxide and a tertiary amine. . In some cases, Lewis acids such as aluminum chloride and tin chloride can be used as a catalyst. However, the type of solvent in the reaction, reaction temperature, reaction time, type of sulfonating agent and the like differ depending on the type of pigment and the reaction system.

  The amount of the treatment agent added in the pigment surface treatment is preferably from 0.1 to 100% by weight, more preferably from 0.1 to 10% by weight, based on the colorant.

  The colorant used in the present invention can also be used as a master batch combined with a resin. As the binder resin to be kneaded together with the production of the masterbatch or the masterbatch, in addition to the modified and unmodified polyester resins mentioned above, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and polymers of substituted products thereof; Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α- Chloromethyl methacrylate copolymer, Tylene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-malein Styrene copolymers such as acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, poly Acrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. The

  The master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force to obtain a master batch. In this case, an organic solvent can be used in order to enhance the interaction between the colorant and the resin. Also known as the flushing method, an aqueous paste containing a colorant water is mixed and kneaded together with a resin and an organic solvent, and the colorant is transferred to the resin side to remove moisture and the organic solvent component. Since the wet cake can be used as it is, it does not need to be dried and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

(Dispersant)
In the present invention, the colorant is used by dispersing it with a dispersant having an acid value of 30 mgKOH / g or less and an amine value of 1 or more and 100 or less. More preferably, it is a dispersant having an acid value of 20 mgKOH / g or less and an amine value of 10 or more and 50 or less. When the acid value exceeds 30 mgKOH / g, the chargeability under high humidity decreases and the pigment dispersibility becomes insufficient. Also, when the amine value is less than 1 and when the amine value exceeds 100, the pigment dispersibility becomes insufficient. The acid value can be measured by the method described in JIS K0070, and the amine value can be measured by the method described in JIS K7237. The dispersant is preferably highly compatible with the binder resin in terms of pigment dispersibility.

  Specific examples of the dispersant having such requirements include “Ajisper PB821”, “Azisper PB822” (manufactured by Ajinomoto Fine Techno Co.), “Disperbyk-2001” (manufactured by BYK Chemie), and “EFKA-4010”. (Manufactured by EFKA). The dispersant is preferably blended in the toner at a ratio of 0.1 wt% or more and 10 wt% or less with respect to the colorant. When the amount is less than 0.1% by weight, the pigment dispersibility is insufficient. When the amount is more than 10% by weight, the chargeability under high humidity may be lowered. The weight average molecular weight of the dispersant is the maximum molecular weight of the main peak in terms of styrene in gel permeation chromatography, and is preferably from 2,000 to 100,000, more preferably 3,000 or more in pigment dispersibility. In particular, about 5000 to 50,000 is preferable, and 5000 to 30000 is more preferable. When the molecular weight is less than 2000, the polarity increases and the dispersibility of the colorant tends to decrease. When the molecular weight exceeds 100,000, the affinity with the solvent increases and the dispersibility of the colorant tends to decrease.

  The addition amount of the dispersant is preferably 1 part by weight or more and 50 parts by weight or less, and more preferably 5 parts by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the colorant. This is because if the amount is less than 1 part by weight, the dispersibility is lowered, and if it exceeds 50 parts by weight, the chargeability tends to decrease. These dispersants may be used alone or in combination with other dispersants. Examples of other dispersants that can be used include polyester dispersants, acrylic acid, methacrylic acid and / or ester polymers thereof, and colorant derivatives.

  In the present invention, the pigment surface is subjected to an acid treatment, and a pigment dispersant having an acid value and an amine value in a certain range is used, whereby the amine sites of the dispersant are adsorbed on the surface of the acidic pigment, thereby positively charging. In the negatively charged toner, the negatively charged toner may be obstructed because the amount of the dispersant polymer having an amine value that tends to become low on the toner surface is eliminated and the acid site of the dispersant on the toner surface increases. Absent.

  The blending ratio of the colorant and the organic solvent in the colorant dispersion is preferably in the range of 5:95 to 50:50. If the blending ratio of the colorant is less than this, the amount of the dispersion is increased at the time of toner preparation, and the efficiency of toner preparation tends to be lowered. If the blending ratio of the colorant is larger than this, the dispersion of the pigment tends to be insufficient.

  The colorant may be used as a colorant dispersion obtained by previously dispersing only the colorant in an organic solvent, or may be directly dispersed in an organic solvent together with the binder resin, the dispersant, and the dispersion resin. Further, even when the colorant is dispersed in advance, the viscosity may be adjusted by adding a part of a binder resin in order to apply an appropriate shearing force when dispersing the pigment ([Low See Molecular Polyester 1]).

  The particle size of the colorant in the dispersion after dispersing the colorant is desirably 1 μm or less. When the particle size is larger than 1 μm, the particle size of the colorant is increased when the toner is formed, and the image quality is liable to be deteriorated. In particular, the light transmittance of OHP is liable to be lowered. The particle size of the colorant can be determined with a laser Doppler type distribution measuring device “UPA-150” (manufactured by Nikkiso Co., Ltd.).

  In the present invention, a colorant derivative having high affinity for the colorant may be added in order to enhance the interaction between the colorant and the dispersant and to stabilize the colorant in dispersion. Specific examples of the colorant derivative include dimethylaminoethylquinacridone, dihydroquinacridone, carboxylic acid derivatives of anthraquinone, sulfonic acid derivatives of anthraquinone, “Solsperse 5000”, “Solsperse 12000”, “Solsperse 22000” (manufactured by Avicia) , “EFKA-6745”, “EFKA-6746”, “EKKA-6750” (manufactured by EFKA Chemicals), and the like. The amount of the colorant derivative added is preferably from 0.1 to 100% by weight, more preferably from 0.1 to 10% by weight, based on the colorant.

(Release agent)
Further, a wax can be contained together with the binder resin and the colorant. Known waxes can be used as the wax of the present invention, and examples thereof include polyolefin waxes (polyethylene wax, polypropylene wax, etc.); long-chain hydrocarbons (paraffin wax, sazol wax, etc.); carbonyl group-containing waxes. Of these, carbonyl group-containing waxes are preferred.

  Carbonyl group-containing waxes include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18. -Octadecandiol diol distearate, etc.); polyalkanol esters (tristearyl trimellitic acid, distearyl maleate, etc.); polyalkanoic acid amides (ethylene diamine dibehenyl amide, etc.); polyalkylamides (trimellitic acid tristearyl amide, etc.) And dialkyl ketones (such as distearyl ketone). Among these carbonyl group-containing waxes, polyalkanoic acid esters are preferred.

  The melting point of the wax of the present invention is usually 40 to 160 ° C, preferably 50 to 120 ° C, more preferably 60 to 90 ° C. A wax having a melting point of less than 40 ° C. has an adverse effect on heat resistant storage stability, and a wax having a melting point of more than 160 ° C. tends to cause a cold offset when fixing at a low temperature. Further, the melt viscosity of the wax is preferably 5 to 1000 cps, more preferably 10 to 100 cps as a measured value at a temperature 20 ° C. higher than the melting point. Waxes exceeding 1000 cps have poor effects for improving hot offset resistance and low-temperature fixability. The content of the wax in the toner is usually 0 to 40% by weight, preferably 3 to 30% by weight.

The softening point Tm of the release agent in the present invention is determined by the peak top indicating the maximum endotherm of the DSC curve in differential scanning calorimetry (DSC). The measurement was performed under the following measurement conditions using TA-60WS and DSC-60 manufactured by Shimadzu Corporation.
Measurement conditions Sample container: Aluminum sample pan (with lid)
Sample amount: 5mg
Reference: Aluminum sample pan (alumina 10mg)
Atmosphere: Nitrogen (flow rate 50 ml / min)
Temperature conditions Starting temperature: 20 ° C
Temperature increase rate: 10 ° C / min
End temperature: 150 ° C
Holding time: None Temperature drop: 10 ° C / min
End temperature: 20 ° C
Holding time: None Temperature increase rate: 10 ° C / min
End temperature: 150 ° C
The measurement results were analyzed using the data analysis software (TA-60, version 1.52) manufactured by Shimadzu Corporation. The analysis method specifies a range of ± 5 ° C. around the point showing the maximum peak of the DrDSC curve which is the DSC differential curve of the second temperature rise, and obtains the peak temperature using the peak analysis function of the analysis software. Next, the maximum endothermic temperature of the DSC curve is determined using the peak analysis function of the analysis software in the range of the peak temperature + 5 ° C. and −5 ° C. in the DSC curve. The temperature indicated here corresponds to the Tm of the wax.

(Charge control agent)
The toner of the present invention may contain a charge control agent as necessary. Known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified 4 Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives.

  Specifically, Nitronine-based dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E- 84, E-89 of phenol-based condensate (above, manufactured by Orient Chemical Industries), TP-302, TP-415 of quaternary ammonium salt molybdenum complex (above, manufactured by Hodogaya Chemical Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, quinaclide And azo pigments, and other high molecular compounds having a functional group such as a sulfonic acid group, a carboxyl group, and a quaternary ammonium salt.

  In the present invention, the amount of charge control agent used is determined by the toner production method including the type of binder resin, the presence or absence of additives used as necessary, and the dispersion method, and is uniquely limited. However, it is preferably used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the main charge control agent is reduced, the electrostatic attraction force with the developing roller is increased, the developer fluidity is lowered, and the image density is lowered. Invite. These charge control agents can be melted and kneaded with a masterbatch and resin, and then dissolved and dispersed. Of course, they can be added when dissolved and dispersed directly in an organic solvent. You may let them.

(Resin fine particles)
The resin fine particles used in the present invention are added in the production process in order to control the toner shape (circularity, particle size distribution, etc.), etc., and have a glass transition point (Tg) of 30 to 70 ° C. If the weight average molecular weight is 8000 to 400,000, the glass transition point (Tg) is less than 30 ° C. and / or the weight average molecular weight is less than 8000, the storage stability of the toner is deteriorated and stored. In addition, blocking occurs in the developing machine. When the glass transition point (Tg) is 70 ° C. or higher and / or the weight average molecular weight is 400,000 or more, the resin fine particles inhibit the adhesiveness to the fixing paper, and the minimum fixing temperature increases.

  It is very preferable that the residual ratio with respect to the toner particles is 0.5 to 5.0% by weight. When the residual ratio is less than 0.5% by weight, the storability of the toner deteriorates, blocking occurs during storage and in the developing machine, and when the residual amount is 5.0% by weight or more, the resin The fine particles inhibit the exudation of the wax, and the effect of releasing the wax cannot be obtained, and the occurrence of offset is observed.

  The residual rate of the resin fine particles can be measured by analyzing a substance caused by the resin fine particles, not by the toner particles, using a pyrolysis gas chromatograph mass spectrometer, and calculating from the peak area. The detector is preferably a mass spectrometer, but is not particularly limited.

  The resin fine particles may be any resin as long as it can form an aqueous dispersion, and may be a thermoplastic resin or a thermosetting resin. For example, vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimides Examples thereof include resins, silicon-based resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, and polycarbonate resins. As the resin fine particles, two or more of the above resins may be used in combination. Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferred because an aqueous dispersion of fine spherical resin particles is easily obtained.

The particle size of the resin fine particles is preferably 5 to 500 nm. When the average particle size of the resin fine particles is less than 5 nm, the resin fine particles remaining on the toner surface become a film or cover the entire toner surface, and the release agent fine particles are formed between the binder resin component in the toner and the fixing paper. Adhesion is hindered, the minimum fixing temperature is increased, and the particle size and shape are also difficult to control. Also, if the particle size of the resin fine particles is larger than 500 nm, the resin fine particles remaining on the toner surface largely protrude as convex portions, or the resin fine particles remain as a multilayered layer in a rough state. Desorption of mold fine particles is observed.
The particle size of the resin fine particles can be measured using a laser Doppler particle size distribution measuring instrument (Nikkiso Co., Ltd.).
Method:
(1) The sample is diluted with ion-exchanged water, and the solid content of the resin fine particles is adjusted to 0.6% (set in the range of 0.5% to 1.0%).
(2) Measuring conditions of measuring instrument Distribution display: Volume Number of channels: 52
Measurement time: 30 sec
Particle refractive index: 1.81
Temperature: 25 ° C
Particle shape: non-spherical viscosity (CP): 0.8750
Solvent refractive index: 1.333
Solvent name: Water
(3) Add the sample diluent to be measured using a dropper or syringe so that it falls within (1-100) while watching the sample loading of the measuring instrument.

  The vinyl resin is a polymer obtained by homopolymerization or copolymerization of a vinyl monomer, such as a styrene- (meth) acrylate resin, a styrene-butadiene copolymer, a (meth) acrylic acid-acrylate polymer, Examples include styrene-acrylonitrile copolymers, styrene-maleic anhydride copolymers, styrene- (meth) acrylic acid copolymers, and the like.

(Inorganic fine particles)
In order to assist the heat resistant storage stability and chargeability of the colored particles obtained in the present invention, inorganic fine particles can be used in the production process. The primary particle diameter of the inorganic fine particles is preferably 0.5 to 200 nm, particularly preferably 0.5 to 50 nm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The proportion of the inorganic fine particles used is preferably 0.01 to 5% by weight of the toner, and particularly preferably 0.01 to 2.0% by weight.

  Specific examples of inorganic fine particles include, for example, tricalcium phosphate, colloidal silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica. And wollastonite, diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride, and hydroxyapatite.

(BET specific surface area)
The toner of the present invention preferably has a BET specific surface area of 0.5 to 6.0 (m ² / g), and if the BET specific surface area is less than 0.5 (m ² / g), the presence or addition of coarse particles When the amount exceeds 6.0 (m ² / g), the image quality is likely to be affected by the presence of fine particles, the presence of additives, and surface irregularities.
The BET specific surface area of the toner of the present invention can be obtained by measuring using a device capable of complying with JIS standards (Z8830 and R1626) such as NOVA series manufactured by Yuasa Ionics.

(External additive)
In the present invention, external additives such as a fluidizing agent, a cleaning property improving agent, and a charge control agent can be externally added to the toner formed using the liquid medium. For example, in order to assist fluidity and developability of the colored particles obtained in the present invention, polymer fine particles such as polystyrene, methacrylic ester and acrylic ester obtained by soap-free emulsion polymerization, suspension polymerization and dispersion polymerization are used. Examples of the polymer particles include copolymers, polycondensation systems such as silicone, benzoguanamine, and nylon, and thermosetting resins.

  Such a fluidizing agent performs surface treatment to increase hydrophobicity, and can prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having an alkyl fluoride group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferable surface treatment agents. .

  Examples of the cleaning property improver for removing the developer after transfer remaining on the photoreceptor or the primary transfer medium include, for example, zinc stearate, calcium stearate, fatty acid metal salts such as stearic acid, such as polymethyl methacrylate fine particles, polystyrene fine particles, etc. And polymer fine particles produced by soap-free emulsion polymerization. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

(Volume average particle diameter, number average particle diameter of toner)
Further, the toner of the present invention has a volume average particle diameter (Dv) of 3.0 μm or more and 8.0 μm or less, and a ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn). Is preferably 1.00 or more and 1.30 or less. By using a toner having such a particle size and particle size distribution, it has excellent heat-resistant storage stability, low-temperature fixability, and hot offset resistance, and particularly excellent gloss when used in a full-color copying machine. Sex is obtained. In general, it is said that the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning properties. is there. In addition, when the volume average particle size is smaller than the range of the present invention, in the case of a two-component developer, the toner is fused to the surface of the magnetic carrier during a long period of stirring in the developing device, and the charging ability of the magnetic carrier is reduced. When used as a developer, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur. On the contrary, when the volume average particle size of the toner is larger than the range of the present invention, it becomes difficult to obtain a high-resolution and high-quality image and the balance of the toner in the developer is performed. In many cases, the variation in toner particle size becomes large. On the other hand, if Dv / Dn exceeds 1.30, the charge amount distribution becomes wide and the resolving power decreases, which is not preferable.
The average particle size and particle size distribution of the toner can be measured using a Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). In the present invention, a Coulter counter TA-II type was used and connected to an interface (manufactured by Nikka Giken) and a personal computer (PC9801: manufactured by NEC) for outputting the number distribution and volume distribution.

  The volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner of the present invention are measured with a particle size measuring device (“Multisizer III”, manufactured by Beckman Coulter, Inc.) at an aperture diameter of 100 μm, and analysis software ( Beckman Coulter Mutlisizer 3 Version 3.51) was used for analysis. Specifically, 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) was added to a glass 100 ml beaker, 0.5 g of each toner was added, and the mixture was stirred with a micropartel. Subsequently, 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.). The dispersion was measured using the Multisizer III and Isoton III (manufactured by Beckman Coulter) as the measurement solution. In the measurement, the toner sample dispersion was dropped so that the concentration indicated by the apparatus was 8 ± 2%. In this measurement method, it is important that the concentration is 8 ± 2% from the viewpoint of the reproducibility of the particle size. Within this concentration range, no error occurs in the particle size.

(Average circularity of toner particles) Refer to Japanese Patent Application Laid-Open No. 2005-3751 The average circularity of toner particles is 0.95 to 0.995 because dot reproducibility is excellent and transferability is also good. From the viewpoint of obtaining Such a toner having a high average circularity is liable to slip on the surface of a frictional charging member such as a magnetic carrier, which is disadvantageous in terms of charging speed and charging level. However, by having the surface properties of the toner particles according to claim 1, a sufficient triboelectric chargeability can be obtained, and a toner excellent in developability and transferability can be obtained. When the average circularity is less than 0.95 and the toner is separated from the spherical shape, it is difficult to obtain a high-quality image with sufficient transferability or dust. Such irregularly shaped particles have many points of contact with the smooth medium on the photoreceptor and the charge concentrates on the tip of the protrusion, so van der Waals force and mirror force are more than those with relatively spherical particles. Wearing power is high. For this reason, in the electrostatic transfer process, the spherical particles are selectively moved in the toner in which the amorphous particles and the spherical particles are mixed, and the character portion and the line portion image are lost. Further, the remaining toner has to be removed for the next development step, and there arises a problem that a cleaning device is necessary and the toner yield (the ratio of toner used for image formation) is low.

The average circularity in the present invention is measured using a flow type particle image analyzer (“FPIA-2100”; manufactured by Sysmex Corporation) and analyzed using analysis software (FPIA-2100 Data Processing Program for FPIA version 00-10). Went. Specifically, 0.1 to 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) is added to a glass 100 ml beaker, and each toner 0.1 to 0 is added. 0.5 g was added and stirred with a microspatel, and then 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). The shape and distribution of the toner were measured using the FPIA-2100 until the density of the dispersion was 5000 to 15000 / μl. In this measurement method, it is important that the concentration of the dispersion liquid is 5000 to 15000 / μl from the viewpoint of measurement reproducibility of the average circularity. In order to obtain the dispersion concentration, it is necessary to change the conditions of the dispersion, that is, the amount of surfactant to be added and the amount of toner. The amount of the surfactant varies depending on the hydrophobicity of the toner as in the measurement of the toner particle diameter described above. If it is added in a large amount, noise due to bubbles is generated. If the amount is too small, the toner cannot be sufficiently wetted. It becomes insufficient. Further, the toner addition amount differs from the particle size, and it is necessary to decrease the small particle size and increase the large particle size. When the toner particle size is 3 to 7 μm, the toner amount is 0.1 to 0. By adding 0.5 g, the dispersion concentration can be adjusted to 5000 to 15000 / μl.
The sample dispersion is allowed to pass through a flow path (expanded along the flow direction) of a flat and flat transparent flow cell (thickness: about 200 μm). In order to form an optical path that passes across the thickness of the flow cell, the strobe and the CCD camera are mounted on the flow cell so as to be opposite to each other. While the sample dispersion is flowing, strobe light is irradiated at 1/30 second intervals to obtain an image of the particles flowing through the flow cell, so that each particle has a certain range parallel to the flow cell. Photographed as a two-dimensional image. From the area of the two-dimensional image of each particle, the diameter of a circle having the same area is calculated as the equivalent circle diameter. In about 1 minute, the equivalent circle diameter of 1200 or more particles can be measured, and the number based on the equivalent circle diameter distribution and the ratio (number%) of particles having a prescribed equivalent circle diameter can be measured. As shown in Table 1, the results (frequency% and cumulative%) can be obtained by dividing the 0.06-400 μm range into 226 channels (divided into 30 channels for one octave). In actual measurement, particles are measured in the range where the equivalent circle diameter is 0.60 μm or more and less than 159.21 μm.

(Production method)
The toner binder (binder resin) can be produced by the following method. The polyol (1) and the polycarboxylic acid (2) are heated to 150 to 280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and the generated water is distilled off as necessary. Thus, a polyester having a hydroxyl group is obtained. Next, this is reacted with polyisocyanate (3) at 40 to 140 ° C. to obtain a prepolymer (A) having an isocyanate group.
The dry toner of the present invention can be produced by the following method, but is not limited thereto.

(Toner production method in aqueous medium)
The aqueous phase used in the present invention is preferably used by adding organic fine particles (resin fine particles) in advance. The water used for the aqueous phase may be water alone, or a solvent miscible with water may be used in combination. Examples of miscible solvents include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.), and the like.

  A toner particle is a dispersion liquid in which an oily dispersoid made of an organic solvent containing a polyester prepolymer (A) having an isocyanate group dissolved or dispersed in an organic solvent in an aqueous phase is dispersed in a droplet form in an aqueous medium. It is obtained by reacting the prepolymer (A) therein with the amines (B). As a method for stably forming the dispersoid droplets composed of the polyester prepolymer (A) in the aqueous phase, the composition liquid of the toner raw material composed of the polyester prepolymer (A) dissolved or dispersed in an organic solvent is aqueous. In addition to the phase, there may be mentioned a method of dispersing by shearing force. Polyester prepolymer (A) dissolved or dispersed in an organic solvent and other toner materials (hereinafter referred to as toner materials), a colorant masterbatch, a release agent, a charge control agent, unmodified polyester The resin or the like may be mixed when forming the droplet dispersoid in the aqueous phase, but after the toner raw material is mixed in advance and dissolved or dispersed in an organic solvent, the mixture is added to the aqueous phase. It is more preferable to disperse. In the present invention, other toner raw materials such as a colorant, a release agent, and a charge control agent do not necessarily have to be mixed when forming particles in the aqueous phase, but after the particles are formed. , May be added. For example, after forming particles containing no colorant, the colorant can be added by a known dyeing method.

  The dispersion method is not particularly limited, and known equipment such as a low-speed shear type, a high-speed shear type, a friction type, a high-pressure jet type, and an ultrasonic wave can be applied. In order to make the particle size of the droplet-like dispersoid 2 to 20 μm, a high-speed shearing type is preferable. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C. Higher temperatures are preferred in that the dispersion of the polyester prepolymer (A) has a low viscosity and is easy to disperse.

  The amount of the aqueous phase used relative to 100 parts of the organic solvent (oil-based phase) of the toner composition raw material containing the polyester prepolymer (A) is usually 50 to 20000 parts by weight, preferably 100 to 10,000 parts by weight. If the amount is less than 50 parts by weight, the dispersed state of oil droplets is poor, and toner particles having a predetermined particle size cannot be obtained. If it exceeds 20000 parts by weight, it is not economical. Moreover, a dispersing agent can also be used as needed. It is preferable to use a dispersant because the particle size distribution becomes sharp and the dispersion is stable.

  Anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates and phosphates as dispersants for emulsifying and dispersing the oily phase in which the toner composition raw material is dispersed (or dissolved) in the aqueous phase; Amine salt types such as alkylamine salts, aminoalcohol fatty acid derivatives, polyamine fatty acid derivatives, imidazoline, alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride Nonionic surfactants such as quaternary ammonium salt type cationic surfactants, fatty acid amide derivatives, polyhydric alcohol derivatives such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N- Alkyl -N, amphoteric surfactants such as N- dimethyl ammonium betaine.

  Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [omega-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-hydroxyethyl) -Fluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is mentioned.

  Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (Daikin Kogyo Co., Ltd.), Mega-Fac F-l0, F-l20, F-113, F-191, F-812, F-833 (Dainippon Ink Co., Ltd.), Xtop EF-102 , 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fagento F-100, F150 (manufactured by Neos).

  Examples of cationic surfactants include aliphatic primary, secondary or secondary amine acids having fluoroalkyl groups, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts, and benzas. Luconium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (Asahi Glass), Florard FC-135 (Sumitomo 3M), Unidyne DS-202 (Daikin Industries) , Megafac F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products Co., Ltd.), Footgent F-300 (Neos Co., Ltd.), and the like.

  Further, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like can be used as an inorganic compound dispersant that is hardly soluble in water.

  Further, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloroacrylate 2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N -Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or esters of compounds containing vinyl alcohol and carboxyl groups For example, vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, ethylene Homopolymers or copolymers such as those having a nitrogen atom such as imine or a heterocyclic ring thereof, polyoxyethylene, polyoxypropylene, polyethylene Oxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonyl phenyl ester Polyoxyethylenes such as, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

  In addition, when an acid such as calcium phosphate salt or an alkali-soluble substance is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. To do. It can also be removed by operations such as enzymatic degradation.

  When a dispersant is used, the dispersant may remain on the surface of the toner particles, but it is preferable from the charged surface of the toner that the dispersant is washed and removed after the elongation and / or crosslinking reaction.

  The elongation and / or cross-linking reaction time is selected depending on the reactivity of the isocyanate group structure of the prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. is there. The reaction temperature is usually 0 to 150 ° C., preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

  In order to remove the organic solvent from the obtained emulsified dispersion, a method in which the temperature of the entire system is gradually raised to completely evaporate and remove the organic solvent in the droplets can be employed. Alternatively, the emulsified dispersion can be sprayed into a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, and the aqueous dispersant can be removed by evaporation together. . As a dry atmosphere in which the emulsified dispersion is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, or the like, in particular, various air currents heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used is generally used. Sufficient quality can be obtained by short-time treatment such as spray dryer, belt dryer, rotary kiln.

  When the particle size distribution at the time of emulsification dispersion is wide and washing and drying processes are performed while maintaining the particle size distribution, the particle size distribution can be adjusted by classification into a desired particle size distribution.

In the classification operation, the fine particle portion can be removed in the liquid by a cyclone, a decanter, centrifugation, or the like. Of course, the classification operation may be performed after obtaining the powder as a powder after drying. The unnecessary fine particles or coarse particles obtained can be returned to the kneading step and used for the formation of particles. At that time, fine particles or coarse particles may be wet.
The dispersant used is preferably removed from the obtained dispersion as much as possible, but it is preferable to carry out it simultaneously with the classification operation described above.

  Mixing or giving mechanical impact force to the powder mixture after drying with different types of particles such as release agent fine particles, charge control fine particles, fluidizing agent fine particles, and colorant fine particles By immobilizing and fusing on the surface, it is possible to prevent detachment of foreign particles from the surface of the resulting composite particle.

  Specific means include a method of applying an impact force to the mixture by blades rotating at high speed, a method of injecting and accelerating the mixture in a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) is modified to reduce the grinding air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron system (Made by Kawasaki Heavy Industries, Ltd.), automatic mortar and the like.

(Carrier for two components)
When the toner of the present invention is used for a two-component developer, it may be used by mixing with a magnetic carrier, and the content ratio of the carrier and the toner in the developer is 1 to 10 wt. Part is preferred.
As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used. Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin.

  Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resin such as vinyl chloride, polyester resin such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resin, polyethylene resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, polytrifluoroethylene resin, polyhexa Fluoropropylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride Fluoro such as terpolymers of emission and non-fluoride monomers including, and silicone resins. Moreover, you may contain electrically conductive powder etc. in coating resin as needed.

  As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance. The toner of the present invention can also be used as a one-component magnetic toner that does not use a carrier or a non-magnetic toner.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example and a comparative example, these each example is not for limiting this invention, and is for making an understanding of this invention easy.

Examples and Comparative Examples-Synthesis of Resin Fine Particle Emulsion-
Production Example 1
In a reaction vessel equipped with a stirrer and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours to give a vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). An aqueous dispersion [resin fine particle dispersion 1] was obtained. The volume average particle diameter of [resin fine particle dispersion 1] measured with LA-920 was 105 nm. A portion of [resin fine particle dispersion 1] was dried to isolate the resin component. The resin content had a Tg of 59 ° C. and a weight average molecular weight of 150,000.

-Adjustment of aqueous phase-
Production Example 2
990 parts of water, 83 parts of [resin fine particle dispersion 1], 37 parts of 48.5% aqueous solution of sodium dodecyldiphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate were mixed and stirred. A liquid was obtained. This is designated as [Aqueous Phase 1].

~ Synthesis of low molecular weight polyester ~
Production Example 3
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts terephthalic acid, 46 parts adipic acid and dibutyl 2 parts of tin oxide was added, reacted at 230 ° C. for 8 hours at normal pressure, and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg. Then, 44 parts of trimellitic anhydride was added to the reaction vessel, and 2 parts at 180 ° C. and normal pressure. By reacting for a time, [low molecular weight polyester 1] was obtained. [Low molecular polyester 1] had a number average molecular weight of 2500, a weight average molecular weight of 6700, a Tg of 43 ° C., and an acid value of 25.

~ Synthesis of intermediate polyester ~
Production Example 4
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen introduction tube, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, 22 parts of trimellitic anhydride Then, 2 parts of dibutyltin oxide was added, reacted at 230 ° C. for 8 hours at normal pressure, and further [intermediate polyester 1] reacted for 5 hours at a reduced pressure of 10 to 15 mmHg. [Intermediate Polyester 1] had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, Tg of 55 ° C., an acid value of 0.5, and a hydroxyl value of 51.

  Next, 410 parts of [intermediate polyester 1], 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. Polymer 1] was obtained. [Prepolymer 1] had a free isocyanate weight% of 1.53%.

~ Synthesis of ketimine ~
Production Example 5
In a reaction vessel equipped with a stirrer and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 418.

~ Pigment treatment ~
Production Example 6
182.7 parts of 2-methoxy-4-nitro-aniline and 5.1 parts of 2-nitro-4-methylaniline are added to a mixture of 1,300 parts of water and 290 parts of 35% hydrochloric acid, and then stirred. Cool to 0 ° C. and add 80 parts of sodium nitrite to diazotize. Separately, 241.8 parts of 2-methoxyacetoacetanilide is added to 5,000 parts of water, dissolved together with 48 parts of sodium hydroxide, and then precipitated by adding a mixture of 196 parts of acetic acid and 196 parts of water. A suspension of the coupling component is obtained. The diazo solution, which has become clear, is added to the acidic suspension of the above coupling component by flowing down within 15 hours to 2 hours at 15 ° C. with good stirring. After the coupling reaction is completed, pigment treatment is performed using 45 parts of rosin and 13 parts of calcium chloride, the resulting pigment composition is filtered, washed with water, and the yellow azo pigment water-wet pigment paste is separated by filtration. The surface-treated pigment was obtained by drying at 90 ° C.

~ Synthesis of MB ~
Production Example 7
1200 parts water C.I. I. 540 parts of Pigment Yellow PY74 (acid-treated product, manufactured by Sanyo Dye), 108 parts of Ajisper PB822 (amine value: 13, acid value: 16 mg KOH / g manufactured by Ajinomoto Fine Techno Co.) as a dispersant, and 1200 parts of polyester resin In addition, the mixture was mixed with a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.), the mixture was kneaded at 150 ° C. for 30 minutes using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Master Batch 1].

~ Creation of oil phase ~
Production Example 8
In a container in which a stir bar and a thermometer were set, 378 parts of [Low molecular polyester 1], 110 parts of Carnauba WAX, and 947 parts of ethyl acetate were charged, heated to 80 ° C. with stirring, and kept at 80 ° C. for 5 hours. Cooled to 30 ° C. in 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].

  [Raw material solution 1] 1324 parts were transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads were 80% by volume. Pigment red and WAX were dispersed under conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [low molecular weight polyester 1] was added, and one pass was performed with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1]. The solid content concentration of [Pigment / WAX Dispersion 1] (130 ° C., 30 minutes) was 50%.

~ Emulsification⇒Desolvation ~
[Example 1]
[Pigment / WAX Dispersion 1] 749 parts, [Prepolymer 1] 115 parts, [Ketimine Compound 1] 2.9 parts in a container, and TK homomixer (manufactured by Tokushu Kika) at 5,000 rpm for 1 minute After mixing, 1200 parts of [Aqueous phase 1] was added to the container, and mixed with a TK homomixer at 13,000 rpm for 20 minutes to obtain [Emulsion slurry 1].

  [Emulsion slurry 1] was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 45 ° C. for 4 hours to obtain [Dispersion slurry 1]. [Dispersion Slurry 1] had a volume average particle size of 5.99 μm and a number average particle size of 5.70 μm (measured with Multisizer II).

~ Washing⇒Drying ~
[Dispersion Slurry 1] After filtering 100 parts under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(2) To the filter cake of (1) above, 105 hydrochloric acid was added to adjust the pH to 2.8, and the mixture was mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes) and then filtered.
(3) Add 300 parts of ion exchanged water to the filter cake of (2) above, mix with TK homomixer (10 minutes at 12,000 rpm), and then filter twice to obtain [Filter cake 1]. It was.
[Filtration cake 1] was dried at 45 ° C. for 48 hours in a circulating drier and sieved with a mesh having a mesh size of 75 μm to obtain [Toner 1].

~ Pigment treatment ~
Production Example 9
In a 10 liter kneader, 500 parts of crude copper phthalocyanine blue (purity 95%) was added together with 2000 parts of sodium chloride and 550 parts of diethylene glycol, kneaded at 100 ° C. for 4 hours, then 25 parts of natural rosin was added, and kneaded for 30 minutes. It was. The resulting mixture is taken up in 10,000 parts of water and stirred at 80 ° C. until the salt and diethylene glycol are dissolved. Further, 50 parts of 98% sulfuric acid was added and stirred for 1 hour, followed by filtration and washing with water until neutrality to obtain a paste-like pigment composition. This was further dried and pulverized to obtain 490 parts of a pigment composition.

~ Synthesis of MB ~
Production Example 10
1200 parts of water, C.I. I. Pigment Blue PB15: 3 (acid-treated product, manufactured by Dainichi Seika Co., Ltd.) 540 parts, Dispersant “Ajisper PB822” (amine value: 13, acid value: 16 mgKOH / g, Ajinomoto Fine Techno Co., Ltd.) 108 parts, polyester 1200 parts of resin was added and mixed with a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.). The mixture was kneaded at 150 ° C. for 30 minutes using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 2].

[Example 2]
[Toner 2] was obtained in the same manner as in Example 1 except that [Master batch 2] was used instead of [Master batch 1] in Example 1.

~ Pigment treatment ~
Production Example 11
After 20.0 parts of 2-amino-5-methylbenzenesulfonic acid is dispersed in 200 parts of water, 22.0 parts of 20% hydrochloric acid is added, and 25.1 parts of 30% aqueous sodium nitrite solution is added dropwise while maintaining the temperature at 0 ° C. A diazo liquid was obtained. Next, after 20.6 parts of 2-hydroxynaphthoic acid was dispersed in 242 parts of water at 60 ° C., 11.5 parts of 48% aqueous sodium hydroxide solution was added to obtain a coupler solution. The coupler solution was cooled to 0 ° C., and the diazo solution was added dropwise with stirring. After stirring for 60 minutes at 0 ° C. to complete the coupling reaction, 40 parts of 10% rosin soda aqueous solution was added and stirred for 60 minutes. To obtain a suspension.

  A solution prepared by dissolving 18.6 parts of calcium chloride in 70 parts of water was added to this suspension, and the mixture was stirred for 60 minutes to complete the rake reaction. After completion of the rake reaction, the mixture was stirred while heating at 80 ° C. for 60 minutes to obtain a suspension of calcium lake azo pigment (CI Pigment Red 57: 1) in water. This suspension was separated by filtration, and the coagulated product was dried at 90 ° C. to obtain a surface-treated pigment.

~ Synthesis of MB ~
Production Example 12
1200 parts of water, C.I. I. Pigment Red PR57: 1 (acid-treated product, manufactured by Dainippon Ink & Chemicals, Inc.) 540 parts, “Disperbyk-2001” as a dispersant (amine value: 29, acid value: 19 mgKOH / g, manufactured by Big Chemie) 108 parts, 1,200 parts of polyester resin was added, mixed with a Henschel mixer (Mitsui Mining Co., Ltd.), the mixture was kneaded at 150 ° C. for 30 minutes using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 3]. .

Example 3
[Toner 3] was obtained in the same manner as in Example 1 except that [Masterbatch 3] was used instead of [Masterbatch 1] in Example 1.

[Comparative Example 1]
[Toner 4] was obtained in the same manner as in Example 1 except that the untreated pigment was used.

[Comparative Example 2]
[Toner 5] was obtained in the same manner as in Example 2 except that the untreated pigment was used.

[Comparative Example 3]
[Toner 6] was obtained in the same manner as in Example 3 except that the untreated pigment was used.

[Comparative Example 4]
[Toner 7] was obtained in the same manner as in Example 1 except that the dispersant was changed to “Azisper PB711” (amine value: 45, manufactured by Ajinomoto Fine Techno Co., Ltd.).

[Comparative Example 5]
[Toner 8] was obtained in the same manner as in Example 2 except that the dispersant was changed to “Azisper PB711” (amine value: 45, manufactured by Ajinomoto Fine Techno Co., Ltd.).

[Comparative Example 6]
[Toner 9] was obtained in the same manner as in Example 3, except that the dispersant was changed to “Disperbyk-2000” (amine value: 4, manufactured by Big Chemie).

(Evaluation of toner)
10 g of each toner thus obtained and 100 g of ferrite carrier were mixed in an environment having a temperature of 28 ° C. and a humidity of 80%, and the charge amount of the toner was measured by a blow-off method. In addition, the charge distribution at this time was sharp. The particle diameter of the toner was measured using a particle size measuring device “Coulter Counter TAII” manufactured by Coulter Electronics Co., Ltd., with an aperture diameter of 100 μm. The volume average particle diameter and the number average particle diameter were determined by the particle size measuring instrument. The surface shape of the toner was observed with a scanning electron microscope.

The image density is 1.0 ± 0.1 mg / cm using a solid image on a plain paper and a thick paper transfer paper (Ricoh type 6200 and NBS Ricoh copy printing paper <135>) using Ricoh's imgio Neo 450. The toner is adjusted so that the toner of No. ² is developed, the temperature of the fixing belt is adjusted to be variable, a solid image is output, and the image density is measured by X-Rite (manufactured by X-Rite). This was measured at five points for each color alone, and the average was obtained for each color.

  Next, 1 part by weight of “Silica R972” (manufactured by Nippon Aerosil Co., Ltd.) as an external additive is added to 100 parts by weight of the toner, and the silica externally added toner mixed for 1 minute by a sample mill is used as an electrophotographic full-color copying machine “imageio Fixing was performed without a fuser oil for fixing with a modified machine of Neo 450 "(manufactured by Ricoh), and an OHP fixed image was formed.

The dispersibility of the colorant was determined by observation with a transmission electron microscope of the toner cross section. Specifically, the toner sample was embedded with an epoxy resin, the cross section was cut, and observed with a transmission electron microscope at an acceleration voltage of 15 kV. As a result, when the transmission electron micrograph showing the particle structure of the toner of Example 1 and the transmission electron micrograph showing the particle structure of the toner of Comparative Example 1 were compared, the toner of Comparative Example 1 had a colorant aggregation. In the toner of Example 1, the colorant is uniformly distributed in the toner, and no local aggregation of the colorant is observed. It was confirmed that the dispersion state was good. The dispersion state of the colorant was similarly confirmed for the toners of other examples and comparative examples.
The turbidity was measured by fixing a solid color image on a transparent sheet for OHP and using a turbidity measuring apparatus. These evaluation results are shown in Table 1.

From these examples and comparative examples, it can be seen that the electrophotographic toner of the present invention has good dispersion of the colorant in the toner, excellent chargeability, and uniform charge distribution. Toners that have been dispersed and optimized with an acid-treated pigment and a pigment dispersant with a certain range of acid and amine values keep a stable charge amount, while non-optimized toners have uneven distribution of pigment near the toner surface. Or a stable charge amount due to the amine site of the dispersant cannot be maintained. This is because even if high pigment dispersion is achieved, the amine sites of the dispersant adversely affect the charge depending on the combination of the pigment surface state (acidic, basic, etc.) and the dispersant. In addition, it can be seen that the toners of Examples 1 to 3 are excellent in color developability and light transmittance after being fixed to the OHP sheet.

Claims (17)

  In a toner produced in an aqueous medium and comprising at least a binder resin and a colorant, 50 to 100% by weight of the binder resin is a polyester resin, and the colorant is a pigment whose surface is treated with an acid; and The colorant is a toner added with a dispersant, wherein the dispersant has an acid value of 1 to 30 mgKOH / g or less and an amine value of 1 or more and 100 or less.   The image forming toner according to claim 1, wherein the method of producing in the aqueous medium is a dissolution suspension method.   In the method of producing in an aqueous medium, at least an active hydrogen group-containing compound, a polymer having a site capable of reacting with an active hydrogen group, a colorant, and a release agent are dissolved or dispersed in an organic solvent, and the solution or dispersion is dissolved. The liquid is dispersed in the form of droplets in an aqueous medium to form an O / W type dispersion, and the active hydrogen group-containing compound and a polymer having a site capable of reacting with an active hydrogen group are contained in the O / W type dispersion. 3. The image forming toner according to claim 1, further comprising a step of removing the organic solvent, washing and drying after or while reacting.   5. The image according to claim 4, wherein the method of producing in the aqueous medium includes a step of adhering resin fine particles contained in the O / W type dispersion to the toner particle surface of the toner. Toner for forming.   The image forming toner according to claim 1, wherein the dispersant is compatible with the binder resin.   The image forming toner according to claim 1, wherein the dispersant has a weight average molecular weight of 2,000 to 100,000.   The image forming toner according to claim 1, wherein the amount of the dispersant added is 1 to 50 parts by weight with respect to 100 parts by weight of the colorant.   The image forming toner according to any one of claims 1 to 7, wherein the dispersant is contained in the toner in a proportion of 0.1 wt% to 10 wt%.   Pigment Yellow PY74, Yellow PY93, PY128, PY139, PY155, PY180, PY185, Pigment Red PR57: 1, PR122, PR146, PR184, PR185, PR238, PR269, Pigment Blue PB15: 3, PB15: 4 The toner for image formation according to any one of claims 1 to 8, wherein the toner is selected from the group consisting of:   The image forming toner according to claim 1, further comprising a release agent.   The image forming toner according to claim 10, wherein the release agent has a melting point of 160 ° C. or less.   12. The image forming toner according to claim 4, wherein the resin fine particles have an average particle size of 5 to 500 nm.   The polyester resin includes a modified polyester resin capable of reacting with an active hydrogen group and a non-modified polyester resin, and a weight ratio of the modified polyester resin to the non-modified polyester resin is 5/95 to 75/25. The toner for image formation according to claim 3, wherein the toner is for image formation.   The image forming toner according to claim 13, wherein an acid value of the modified polyester resin and the non-modified polyester resin is 0 to 30 mg KOH / g.   15. The image forming toner according to claim 3, wherein a blending ratio of the colorant and the organic solvent is in a range of 5:95 to 50:50.   16. A one-component developer for developing an electrostatic latent image, comprising the toner for image formation according to any one of claims 3 to 15. 16. A two-component developer for developing an electrostatic latent image, comprising the toner for image formation according to claim 3 and a carrier.