JP2005181839A - Toner for image formation and method for manufacturing the same, and electrostatic latent image developer, image formation method, image forming apparatus and process cartridge using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the dispersibility of a colorant/release agent in toner, to diminish the defects of a conventional technique, and to provide toner having excellent offset properties, chargeability and storage stability and having good color developing properties and OHP transmittance in order to fulfill the requirement of higher performance. <P>SOLUTION: In the toner for image formation containing at least binder resin and a colorant and produced in an aqueous medium, 50 to 100 wt.% of the binder resin is polyester resin and the colorant contains a modified polyurethane type dispersant. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming toner used in electrophotography, a method for producing the same, an electrostatic latent image developer using the electrophotographic toner, an image forming method, an image forming apparatus, and a process cartridge.

  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. Therefore, when the above composition is actually pulverized into particles, a high-range particle size distribution is likely to be formed, and when attempting to obtain a copy image with good resolution and gradation, for example, the particle size There is a disadvantage that the fine powder of 5 μm or less and the coarse powder of 20 μm or more must be removed by classification, resulting in a very low yield. 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 non-uniformly charged, the toner charge distribution 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, etc. 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, there are many cases where the materials used in the conventional toner cannot be used.

  Even if polymerization can be performed using conventional materials, the particle size may not be sufficiently controlled 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 conventional kneading and grinding methods cannot be used basically, and therefore they must be sufficiently compatible with miniaturization, high speed, and colorization. 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, and the background stain of the obtained image becomes poor. 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 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.

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 image forming toner that can sufficiently meet the demand for higher performance has not yet been obtained.
Japanese Patent No. 2537503

  Accordingly, it is an object of the present invention to improve the dispersibility of the colorant / release agent in the toner, greatly improve the drawbacks of the prior art, and meet the demands for higher performance in order to improve offset performance and chargeability. Another object of the present invention is to provide an image forming toner having excellent storage stability, good color development properties and OHP permeability.

  As a result of intensive studies, the present inventors have found that 50 to 100% by weight of the binder resin in the toner is a polyester resin, and a colorant is added by adding a modified polyurethane dispersant having a predetermined acid value and amine value. As a result, the present inventors have found that the dispersibility and dispersion stability are improved.

That is, the electrophotographic toner of the present invention has the following constitution.
(1) In a toner containing at least a binder resin and a colorant produced in an aqueous medium, 50 to 100% by weight of the binder resin is a polyester resin, and further contains a modified polyurethane dispersant. An image forming toner.
(2) The image forming toner as described in (1) above, wherein the modified polyurethane dispersant has an acid value of 30 mgKOH / g or less and an amine value of 1 or more and 100 or less.
(3) The image forming toner according to (1) or (2), wherein the acid value of the colorant is 1 mgKOH / g or more and 30 mgKOH / g or less.

(4) The image-forming toner according to any one of (1) to (3), wherein the modified polyurethane-based dispersant is compatible with a binder resin.
(5) The image forming toner according to any one of (1) to (4), wherein the modified polyurethane dispersant has a weight average molecular weight of 2,000 to 100,000.
(6) The addition amount of the modified polyurethane-based dispersant is 1 part by weight or more and 50 parts by weight or less with respect to 100 parts by weight of the colorant, according to any one of (1) to (5), Image forming toner.

(7) The modified polyurethane dispersant is contained in the toner at a ratio of 0.1% by weight or more and 10% by weight or less, according to any one of (1) to (6), Toner for image formation.
(8) The colorant is selected from Pigment Red PR122, PR269, PR184, PR57: 1, PR238, PR146, PR185, Pigment Yellow PY93, PY128, PY155, PY180, PY74, and Pigment Blue PB15: 3. The image forming toner according to any one of (1) to (7).

(9) The image forming toner as described in any one of (1) to (8) above, further comprising a release agent.
(10) The image forming toner according to (9), wherein the content of the releasing agent is 1 part by weight or more and 40 parts by weight or less with respect to 100 parts by weight of the image forming toner.
(11) The toner for image formation as described in (9) or (10) above, wherein the releasing agent has a melting point of 160 ° C. or lower.

(12) The image forming toner as described in any one of (1) to (11) above, wherein the method for producing the toner in the aqueous medium is a dissolution suspension method.
(13) The method for producing the toner in the aqueous medium may include dissolving a modified polyester resin, a colorant, and a modified polyurethane dispersant having a site capable of reacting with at least a compound having an active hydrogen group in an organic solvent. Disperse, disperse the solution or dispersion in an aqueous medium, and react or after reacting the modified polyester resin having a site capable of reacting with the compound having active hydrogen groups with the compound having active hydrogen groups. The image forming toner according to any one of (1) to (11), wherein the organic solvent is removed, washed, and dried.
(14) The image forming toner as described in (13) above, wherein resin fine particles are contained in the aqueous medium, and these are adhered to the toner surface.
(15) The toner for image formation as described in (14) above, wherein the resin fine particles have an average particle size of 5 to 500 nm.

(16) In the organic solvent, a non-modified polyester resin is dissolved or dispersed together with a modified polyester resin capable of reacting with a compound having an active hydrogen group, and a weight ratio of the modified polyester resin to the non-modified polyester resin. The image forming toner according to any one of (13) to (15), wherein the toner is 5/95 to 75/25.
(17) The toner for image formation as described in (16) above, wherein the acid value of the modified polyester resin and the non-modified polyester resin is 0 to 30 mgKOH / g.

(18) An electrostatic latent image developer comprising the image forming toner according to any one of (1) to (17).
(19) An electrostatic latent image developing two-component developer comprising the image forming toner according to any one of (1) to (17) and a carrier.

(20) In an image forming toner manufacturing method for producing an image forming toner containing at least a binder resin and a colorant in an aqueous medium, 50 to 100% of the binder resin is a polyester resin, and A modified polyurethane dispersant is contained as a method for producing a toner for image formation.
(21) The image forming apparatus as described in (20) above, wherein the modified polyurethane dispersant is a modified polyurethane dispersant having an acid value of 30 mgKOH / g or less and an amine value of 1 or more and 100 or less. Of manufacturing toner.
(22) A toner is produced by preparing an oil phase component by dissolving or dispersing the modified polyurethane dispersant and a colorant in a binder resin, and dispersing the oil phase component in an aqueous medium. The method for producing an image forming toner according to (20) or (21).

(23) An oil phase component is prepared by dissolving or dispersing a colorant dispersion in which the colorant is dispersed in an organic solvent in advance with at least the modified polyurethane dispersant in the organic solvent together with at least the binder resin. The method for producing a toner for image formation as described in (20) or (21) above, wherein the toner is produced by dispersing the oil phase component in an aqueous medium.
(24) The method for producing an image-forming toner as described in (23) above, wherein a mixing ratio of the colorant and the organic solvent is in the range of 5:95 to 50:50 in the colorant dispersion. .
(25) The method for producing an image forming toner for producing an image forming toner containing a binder resin and a colorant in the aqueous medium is a solution suspension method according to any one of (20) to (24). A method for producing the image forming toner according to claim 1.

(26) In the method for producing an image forming toner for producing an image forming toner containing a binder resin and a colorant in the aqueous medium, a site capable of reacting with a compound having at least an active hydrogen group in an organic solvent is provided. A modified polyester system having a site capable of reacting with a compound having an active hydrogen group by dissolving or dispersing the modified polyester resin, colorant, and modified polyurethane-based dispersant, and dispersing the solution or dispersion in an aqueous medium The method according to any one of (20) to (24) above, wherein the organic solvent is removed, washed and dried after reacting the resin with a compound having an active hydrogen group or while reacting the resin. A method for producing the image forming toner according to claim 1.
(27) The method for producing an image forming toner as described in (26) above, wherein resin fine particles are contained in the aqueous medium, and these are adhered to the toner surface.
(28) The method for producing an image forming toner as described in (27) above, wherein the resin fine particles have an average particle diameter of 5 to 500 nm.

(29) A non-modified polyester resin is contained in the organic solvent together with a modified polyester resin capable of reacting with the compound having an active hydrogen group, and a weight ratio of the modified polyester resin to the non-modified polyester resin is determined. The method for producing an image forming toner according to any one of (26) to (28), wherein the toner is 5/95 to 75/25.
(30) The method for producing an image forming toner according to (29), wherein the acid value of the modified polyester resin and the non-modified polyester resin is 0 to 30 mgKOH / g.

(31) At least after charging the photosensitive member, an electrostatic latent image is formed by image exposure, the electrostatic latent image is developed with toner, and then the toner image is transferred onto the transfer member. In the image forming method in which the step of cleaning the photoconductor after transfer is repeatedly performed, the toner is the image forming toner according to any one of (1) to (17).
(32) In an image forming apparatus comprising at least a charging unit, an image exposing unit, a developing unit, a transferring unit, a fixing unit, and an electrophotographic photosensitive member, the developing unit holds toner, and the toner is the above (1) An image forming apparatus comprising the image forming toner according to any one of (17) to (17).
(33) In a process cartridge which integrally supports at least one unit selected from a photosensitive member and a charging unit, a developing unit, and a cleaning unit, and is detachable from the main body of the image forming apparatus, the developing unit uses toner. A process cartridge, wherein the toner is the image forming toner according to any one of (1) to (17).

  The modified polyurethane dispersant used in the present invention can increase the affinity between the dispersant and the binder resin or the colorant by setting the acid value and the amine value within a certain range. The balance with the part can be taken well. As a result, when the modified polyurethane dispersant used in the present invention is added, it exhibits high dispersibility in the colorant, resin, and solvent while suppressing the influence on the chargeability of the toner, thereby dispersing the colorant. It is presumed that the property, dispersion stability and toner fluidity are improved.

  That is, in the electrophotographic toner of the present invention, by adding the modified polyurethane dispersant to the colorant dispersion, the dispersibility of the colorant is improved, and the color developability of the toner and the optical transparency of the OHP are improved. At the same time, since the colorant can be stably dispersed for a long time even during production, the efficiency of particle production is improved.

  In particular, when the toner is produced using the modified polyurethane dispersant of the present invention, the colorant fine particles are uniformly distributed in the toner particles due to the difference in affinity between the colorant and the oil phase component and the colorant and the aqueous medium. Dispersion reduces the amount of colorant exposure on the toner surface. Further, the range of selection of the resin and the colorant is expanded, and it is possible to add other additives such as wax. 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 with good image quality and excellent light transmittance 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 speeding up 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.

  According to this invention, the dispersibility of the colorant is improved, the color developability of the toner and the light transmittance of the OHP are improved, and the colorant dispersion stability in the colorant dispersion is excellent, and the colorant dispersion is stored. Stability is improved and particle production efficiency is increased. Furthermore, the selectivity of the resin and the colorant is wide, and other additives such as wax can be added. At the same time, an oil phase component in which a resin and a colorant are dissolved or dispersed in an organic solvent in which the toner constituent resin is soluble is dispersed in an aqueous medium, and particles are granulated, whereby the colorant and the oil phase are dispersed. Due to the difference in affinity between the components and the colorant and the aqueous medium, the colorant fine particles are uniformly dispersed in the toner particles, and the amount of colorant exposure on the toner surface is reduced. Furthermore, 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. Furthermore, by applying this toner to the developer, an image having a good image quality and excellent light transmittance in OHP can be formed in an image forming method for forming a latent image.

  The toner of the present invention is a toner containing at least a binder resin, a colorant, and a modified polyurethane dispersant produced in an aqueous medium. First, it can react with a compound having at least an active hydrogen group in an organic solvent. A modified polyester-based resin, a colorant, and a modified polyurethane-based dispersant having various sites are dissolved or dispersed, and the solution or dispersion is dispersed in an aqueous medium to have a site capable of reacting with the compound having an active hydrogen group A toner obtained by a method in which the organic solvent is removed, washed and dried after reacting the modified polyester resin with a compound having an active hydrogen group or while reacting will be described.

(Organic solvent)
In the present invention, the organic solvent is not particularly limited as long as it is a solvent capable of dissolving and / or dispersing the toner composition. As a preferable thing, it is preferable from the point that removal is easy that the boiling point of this solvent is less than 150 degreeC. Examples of the solvent include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, methyl acetate, ethyl acetate, methyl ethyl ketone, acetone. , Tetrahydrofuran and the like can be used alone or in combination of two or more. 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 having a site capable of reacting with a compound having an active hydrogen group)
Any site capable of reacting with active hydrogen can be used as long as it is known, and is preferably an isocyanate group, an epoxy group, a carboxylic acid, or an acid chloride group, more preferably an isocyanate group. Therefore, a particularly preferred resin used in the present invention is a 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 polyisocyanate (PIC) reacted with a polyester having active hydrogen. 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.

  Modified polyester (MPE) such as urea-modified polyester is easy to adjust the molecular weight of its polymer component, and is a dry toner, especially oil-less low-temperature fixing characteristics (extensive releasability without a mechanism for applying a release oil to a fixing heating medium) And fixing property). In particular, those obtained by modifying the end of the polyester prepolymer with urea can suppress adhesion to the 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 oxide (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, 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 more 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, as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH], preferably 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  As polyisocyanate (PIC), aliphatic polyisocyanate (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanate (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic Diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; polyisocyanates such as phenol derivatives, oximes, caprolactam, etc. 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. It is a piece. 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.

  The modified polyester such as urea-modified polyester (UMPE) used as the binder resin 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, and more preferably 30,000 to 1,000,000. 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 is usually 20000 or less, preferably 1000 to 10000, and 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.

(Compound having an active hydrogen group)
Examples of the compound having an active hydrogen group that reacts with the modified polyester resin having a site capable of reacting with the compound having an active hydrogen group used in the present invention can react with a reactive group such as an isocyanate group of the modified polyester. Active hydrogen compounds, preferably amines (B) can be used. In the present invention, a urea-modified polyester that is preferably used as a binder resin can be obtained by a reaction between a polyester prepolymer (A) having an isocyanate group and amines (B).

  As amines (B), diamine (B1), trivalent or higher polyamine (B2), aminoalcohol (B3), aminomercaptan (B4), amino acid (B5), and amino acids B1-B5 blocked (B6) etc. are mentioned. Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexylmethane, diamines). Cyclohexane, isophoronediamine, etc.); and aliphatic diamines (ethylenediamine, tetramethylenediamine, hexamethylenediamine, 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 B1 to B5 amino group blocked (B6) include ketimine compounds and oxazoline compounds obtained from the B1 to B5 amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

  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.

  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).

(Non-modified polyester resin)
In the present invention, not only the modified polyester (A) is used alone, but also this (A) and unmodified polyester (C) having an acid value of 0 to 30 mg KOH / g as a binder resin component. It can be included. 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 (PO) and polycarboxylic acid (PC) as in the previous (A) polyester component, and preferred ones are also the same as (A). (C) is not limited to non-modified polyester, but may be modified with a chemical bond other than a urea bond, and may be modified with a urethane bond, for example.

  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 of (A) to (C) is usually 5/95 to 75/25, preferably 10/90 to 25/75, more preferably 12/88 to 25/75, Especially preferably, it is 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 non-modified 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., and THF as a solvent is allowed to flow through the column at this temperature 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 * 10-6.2 * 10 made from 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 the component having a molecular weight of 30000 or more is 1% by weight or more and preferably 3 to 6% by weight although it varies depending on the toner material. If it is less than 1% by weight, sufficient hot offset resistance cannot be obtained, and if it is 10% by weight or more, glossiness and transparency may be deteriorated.

  The number average molecular weight (Mn) of the unmodified polyester is 2000 to 15000, and the value (Mw / Mn) of the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn) is preferably 5 or less. When it exceeds 5, sharp melt property is lacking and 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. Insoluble in THF is effective for hot offset in color toners, but it is definitely negative in terms of gloss and transparency of OHP, but it is effective within 1 to 15% to widen the mold release width. There is also.

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 content of the toner can be adjusted by controlling the elongation and / or crosslinking of the modified polyester by the acid value of the non-modified polyester.
The method for measuring the THF-insoluble content 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 quantitative determination. 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

(Toner and glass transition point of non-modified polyester)
In the present invention, a modified polyester and a non-modified 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 non-modified polyester, and the glass transition point (Tg) of the toner is adjusted by the glass transition point (Tg) of the non-modified polyester. It is possible. 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.

<Measuring method of glass transition point (Tg)>
A method for measuring Tg will be outlined. As an apparatus for measuring Tg, a TG-DSC system TAS-100 manufactured by Rigaku Corporation was used. First, about 10 mg of a sample is placed in an aluminum sample container, which is placed on a holder unit and set in an electric furnace. Next, after heating from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 minutes, and then the sample was cooled to room temperature and left for 10 minutes. DSC measurement was performed by heating to 150 ° C. at a heating rate of 10 ° C./min in a nitrogen atmosphere. Tg was calculated from the tangent of the endothermic curve near Tg and the base line using the TAS-100 system.

(Coloring agent)
As the coloring agent of the present invention, all known dyes and pigments can be 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, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red , Fais red, parachlorol Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, 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, Tolujing 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 , Polyazo red, chrome vermillion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkali blue rake, peacock blue rake, Victoria blue rake, metal free phthalocyanine blue, phthalocyanine blue, fast sky blue, in Dunslen Blue (RS, BC), Indigo, Ultramarine Blue, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake Phthalocyanine green, anthraquinone green, titanium oxide, zinc white, lithopone and mixtures thereof can be used. Particularly effective are Pigment Red PR122, PR269, PR184, PR57: 1, PR238, PR146, PR185, Pigment Yellow PY93, PY128, PY155, PY180, PY74, and Pigment Blue PB15: 3. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant used in the present invention can also be used as a master batch combined with a resin. In the production of the masterbatch, it is preferable to dissolve or disperse the colorant and the modified polyurethane dispersant in the binder resin. As the binder resin to be kneaded together with the production of the masterbatch or the masterbatch, in addition to the above-mentioned modified and non-modified polyester resins, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and substituted polymers thereof. Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Polymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α -Methyl chloromethacrylate copolymer, styrene -Acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid Styrenic copolymers such as ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacryl Acid resins, rosins, modified rosins, terpene resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be used, and these can be used alone or in combination.

  In this master batch, a master batch can be obtained by mixing and kneading a resin for a master batch, a colorant, and a modified polyurethane dispersant under high shearing force. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. In addition, a so-called flushing method, which is a wet cake of a coloring agent, is a method of mixing and kneading an aqueous paste containing water of a coloring agent together with a resin and an organic solvent, transferring the coloring agent to the resin side, and removing moisture and organic solvent components. Can be used as it is, so that it is not necessary to dry and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

Further, the colorant used in the present invention may be used as a dispersion obtained by previously dispersing a colorant and a modified polyurethane dispersant in an organic solvent, and in order to apply an appropriate shearing force when dispersing the pigment. A binder resin may be added and dispersed in an organic solvent.
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 reduced. If the blending ratio of the colorant is larger than this, the dispersion of the pigment tends to be insufficient.

  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 diffraction / scattering particle size distribution measuring device “LA-920” (manufactured by Horiba, Ltd.).

  In order to enhance the interaction between the colorant and the modified polyurethane dispersant and to stabilize the colorant in dispersion, it is preferable to perform a surface treatment of the colorant. 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 resin, and rosin-modified phenolic resin. In particular, an acidic surface treatment agent is preferably used in order to increase the affinity with the pigment dispersant, and the acid value of the colorant is preferably 1 mgKOH / g or more and 30 mgKOH / g or less. The addition amount of the colorant derivative and the surface treatment agent of the colorant is preferably 0.1 to 100% by weight, and more preferably 0.1 to 10% by weight with respect to the colorant.

(Modified polyurethane dispersant)
In the present invention, the colorant is preferably dispersed with a modified polyurethane dispersant having an acid value of 30 mgKOH / g or less and an amine value of 1 to 100. More preferably, it is a modified polyurethane-based dispersant having an acid value of 20 mgKOH / g or less and an amine value of 3 to 60. When the acid value exceeds 30 mgKOH / g, the chargeability under high humidity is lowered and the pigment dispersibility is also insufficient. Also, when the amine value is less than 1 and when the amine value exceeds 60, 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 modified polyurethane dispersant is preferably highly compatible with the binder resin in terms of pigment dispersibility, and is preferably a silane coupling agent having an amino group or a polyurethane derivative such as polyurethane modified with diisocyanate.

The polymer type dispersant will be specifically described as follows.
1) One part of an isocyanate group of a polyisocyanate compound is reacted with a compound having one hydroxyl group, and an unreacted part is further reacted with a compound having an isocyanate group and active hydrogen at both ends. A dispersant obtained by reacting an unreacted isocyanate group with a substituent having active hydrogen and a compound having a tertiary amino group or a heterocyclic group.
2) Polyepoxy having a hydroxyl group at the molecular end obtained by reacting a monocarboxylic acid compound with a monoepoxy compound, an acid anhydride and a lactone, or a compound having a monohydric alcohol, a monoepoxy compound and a lactone, and in some cases Further, a polyester having a hydroxyl group at the molecular end obtained by reacting with an acid anhydride is reacted with a diisocyanate compound, and further a hydroxyl group-containing copolymerizable monomer is reacted to obtain a polyester macromer. It is obtained by reacting an acid anhydride with any one and reacting with glycidyl (meth) acrylate to obtain a polyester macromer, and further copolymerizing a tertiary amino group-containing copolymer monomer with any of the above polyester macromers. Dispersant.
3) Reaction product of monocarboxylic acid compound and lactone, reaction product of monocarboxylic acid compound and acid anhydride and monoepoxy compound, reaction product of monohydric alcohol and acid anhydride and monoepoxy compound, monohydric alcohol and lactone Having a carboxyl group at one end obtained by polymerizing a compound obtained by reacting an acid anhydride with the above reaction product, or a polymerizable vinyl group-containing monomer using a radical chain transfer agent having a carboxyl group and a mercapto group A dispersant obtained by reacting any of the compounds with a polyepoxy compound and then reacting an organic amino compound having one secondary amino group in the molecule.
These three types of dispersants are described in (1) in JP-B-2-19844, (2) in JP-A-4-227774, and (3) in JP-A-7-250953, respectively. Has been.

  Specific examples of the modified polyurethane-based dispersant having such requirements include “EFKA-4060”, “EFKA-4080”, “EFKA-7462”, “EFKA-4015”, “EFKA-4046”, “EFKA-4047”, “EFKA-4055”, “EFKA-4050” (manufactured by EFKA CHEMICALS) and the like can be mentioned.

The modified polyurethane dispersant is preferably blended in the toner at a ratio of 0.1 wt% or more and 10 wt% or less. If the amount is less than 0.1% by weight, the pigment dispersibility is insufficient. If the amount is more than 10% by weight, the chargeability under high humidity may be lowered.
The weight average molecular weight of the modified polyurethane dispersant is the maximum molecular weight of the main peak in terms of styrene conversion weight in gel permeation chromatography, preferably 2000 or more, and more preferably 3000 or more in pigment dispersibility. In particular, about 5000 to 50000 is preferable, and 5000 to 30000 is more preferable. When the molecular weight is less than 500, the polarity becomes high and the dispersibility of the colorant tends to decrease, and when the molecular weight exceeds 100,000, the affinity with the solvent increases and the dispersibility of the colorant tends to decrease.

The amount of the modified polyurethane dispersant added 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 modified polyurethane-based 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, by using a modified polyurethane-based dispersant when preparing the colorant dispersion, most of the dispersant polymer is adsorbed on the colorant particles, and the dispersant polymer having an amine value that tends to be positively charged. Since the abundance on the toner surface is reduced, negative chargeability is not hindered particularly in negatively chargeable toners.

(Release agent)
Further, the toner of the present invention may contain a release agent together with the binder resin and the colorant. As the release agent of the present invention, known ones can be used, such as polyolefin wax (polyethylene wax, polypropylene wax, etc.); long chain hydrocarbon (paraffin wax, sasol wax, etc.); carbonyl group-containing wax, etc. Is mentioned. Of these, carbonyl group-containing waxes are preferred. Examples of the carbonyl group-containing wax include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18. -Octadecanediol distearate, etc.); polyalkanol esters (trimellitic acid tristearyl, distearyl maleate, etc.); polyalkanoic acid amides (ethylenediamine 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.

(Charge control agent)
The toner of the present invention may contain a charge control agent as necessary. All 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). Quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine-based 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 a phenol-based condensate (manufactured by Orient Chemical Industry Co., Ltd.), TP-302 of a quaternary ammonium salt molybdenum complex, TP-415 (manufactured by Hodogaya Chemical Industry 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 primarily by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is uniquely limited. Although it is not a thing, Preferably it is used in 0.1-10 weight part with respect to 100 weight part of 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 dissolved and dispersed after being melt-kneaded with a masterbatch and resin, and of course, they can be added directly when dissolved and dispersed in an organic solvent, or fixed on the toner surface after preparation of toner particles. May be.

(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.), and have a glass transition point (Tg) of 30 to 70 ° C. and a weight average. The molecular weight is preferably 8,000 to 400,000, and when the glass transition point (Tg) is less than 30 ° C. and / or the weight average molecular weight is less than 8,000, the storability of the toner deteriorates, and during storage and Blocking occurs in the developing machine. When the glass transition point (Tg) exceeds 70 ° C. and / or the weight average molecular weight exceeds 400,000, the resin fine particles inhibit the adhesion to the fixing paper, and the minimum fixing temperature increases.

It is important that the resin fine particle residual ratio with respect to the toner particles is 0.5 to 5.0 wt%. When the residual ratio is less than 0.5 wt%, the storage stability of the toner deteriorates, and blocking occurs during storage and in the developing machine. When the residual amount exceeds 5.0 wt%, the resin fine particles Inhibits the exudation of the wax, the effect of releasing the wax is not 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 diameter 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 closely, and the release agent fine particles are contained in the binder resin component and the fixing paper inside the toner. The adhesion lowering temperature 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 diameter of the resin fine particles can be measured as a volume average diameter by a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.).

  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. The primary particle diameter of the inorganic fine particles is preferably 0.5 nm to 200 nm, and particularly preferably 0.5 nm to 50 nm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The use ratio of the inorganic fine particles is preferably 0.01 to 5 wt% of the toner, and particularly preferably 0.01 to 2.0 wt%. 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 order to assist the fluidity and developability of the colored particles obtained in the present invention, polymer fine particles such as soap-free emulsion polymerization, suspension polymerization, dispersion polymerization, polystyrene, methacrylate ester and acrylate ester copolymer Examples thereof include polymer particles such as coalescence, polycondensation systems such as silicone, benzoguanamine, and nylon, and thermosetting resins.
Such a fluidizing agent can be surface-treated to increase hydrophobicity and 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.

(Production method)
The modified polyester resin having a site capable of reacting with the compound having an active hydrogen group used in the present invention can be produced by the following method. Polyol (PO) and polycarboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and the generated water is distilled off as necessary. Thus, a polyester having a hydroxyl group is obtained. Next, this is reacted with polyisocyanate (PIC) at 40 to 140 ° C. to obtain a prepolymer (A) having an isocyanate group.

The 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 used by adding organic 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 the miscible solvent include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.

  The toner particles are obtained by forming a dispersion composed of a polyester prepolymer (A) having an isocyanate group dissolved or dispersed in an organic solvent in an aqueous phase and reacting with amines (B). As a method for stably forming a dispersion comprising a polyester prepolymer (A) in an aqueous phase, a composition of a toner raw material comprising a polyester prepolymer (A) dissolved or dispersed in an organic solvent in an aqueous phase is added. And a method of dispersing by shearing force. Polyester prepolymer (A) dissolved or dispersed in an organic solvent and other toner composition (hereinafter referred to as toner raw material), colorant masterbatch, release agent, charge control agent, unmodified The polyester resin or the like may be mixed when forming the dispersion 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 and dispersed. Is more preferable. 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. It 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 method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. In order to make the particle size of the dispersion 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 toner composition 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 dispersion state of the toner composition is poor, and toner particles having a predetermined particle diameter 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, phosphate esters, alkylamine salts, amino acids as dispersants for emulsifying and dispersing the oily phase in which the toner composition is dispersed in the aqueous phase Alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, quaternary ammonium such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride Nonionic surfactants such as salt-type cationic surfactants, fatty acid amide derivatives, polyhydric alcohol derivatives, such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N − Amphoteric surfactants such as 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 to C11). Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carboxylic acid And its metal salt, perfluoroalkylcarboxylic acid (C7 to C13) and its metal salt, perfluoroalkyl (C4 to C12) sulfonic acid and its metal salt, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-hydroxyethyl ) Perfluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate Etc.
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-l10, F-120, F-, 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 Co., Ltd.), and Fgentent F-100, F-150 (manufactured by Neos).

In addition, as the cationic surfactant, aliphatic primary, secondary or tertiary amine acids that right the fluoroalkyl group, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, Benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (Asahi Glass Co., Ltd.), Florard FC-135 (Sumitomo 3M Co., Ltd.), Unidyne DS-202 (Daikin Industries, Ltd.) ), Megafuck 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 which 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 Bodies such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-acrylate Chloro-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 a carboxyl group, 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, ethyleneimine Homopolymers or copolymers such as those having a nitrogen atom, or a heterocyclic ring thereof, polyoxyethylene, polyoxypropylene, Reoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonyl Polyoxyethylenes such as phenyl esters, 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 generally 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 with a short treatment such as spray dryer, belt dryer or 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 classifying 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.) has been modified to reduce the pulverization air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, etc.

(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. The carrier to toner content ratio in the developer is 1 to 10 weights of toner with respect to 100 parts by weight of carrier. 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 resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride And fluoro such as terpolymers of 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.

  Next, the image forming apparatus and the image forming method of the present invention will be described. For example, in the rotation process of the photosensitive member, the charging unit receives a uniform charge of positive or negative predetermined potential on the peripheral surface, and then receives image exposure light from an image exposure unit such as slit exposure or laser beam scanning exposure, In this way, electrostatic latent images are sequentially formed on the peripheral surface of the photosensitive member, and the formed electrostatic latent image is then developed with toner by a developing unit. The developed toner image is transferred from the paper feeding unit to the photosensitive member, the transfer unit, and the like. During this time, the transfer means sequentially transfers the image onto the transfer material fed in synchronism with the rotation of the photosensitive member. The transfer material that has received the image transfer is separated from the surface of the photosensitive member, introduced into the image fixing means, and fixed on the image, and printed out as a copy (copy). The surface of the photoconductor after the image transfer is cleaned by removing toner remaining after transfer by a cleaning unit, and after being further neutralized, it is repeatedly used for image formation. The image forming method and the image forming apparatus of the present invention use the image forming toner of the present invention in the image formation as described above. A well-known thing can be used as a charging means, an exposure means, a cleaning means, etc.

  In the present invention, among the above-described components such as the photosensitive member, the charging unit, the developing unit, and the cleaning unit, a plurality of components are integrally coupled as a process cartridge, and the process cartridge is configured as a copying machine or a printer. It can be configured to be detachable from the image forming apparatus main body. The developing means holds the image forming toner of the present invention.

Production Example 1 (Synthesis of resin fine particle emulsion)
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, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A 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.

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

Production Example 3 (Synthesis of low molecular weight polyester)
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 Add 2 parts of tin oxide, react at 230 ° C for 8 hours at normal pressure, and further react for 5 hours at 10-15 mmHg reduced pressure, then add 44 parts of trimellitic anhydride to the reaction vessel at 180 ° C at normal pressure. The mixture was reacted for 2 hours to obtain [Low molecular weight polyester 1]. [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.

Production Example 4 (Synthesis of Intermediate Polyester)
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 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, trimellitic anhydride 22 And 2 parts of dibutyltin oxide were 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 to obtain [Intermediate Polyester 1]. [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%.

Production Example 5 (Synthesis of ketimine)
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.

Production Example 6 (Synthesis of MB)
1200 parts of water, C.I. Pigment Red PR269 (manufactured by Dainippon Ink & Chemicals, Inc.) 540 parts, “EFKA-4080” which is a polymer dispersant (modified polyurethane amine value: 3.6 to 4.1, manufactured by EFKA Chemicals) 108 parts polyester resin 1200 Part 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 1].

Production Example 7 (Production of oil phase)
In a container equipped with a stirrer and a thermometer, 378 parts of [Low molecular weight polyester 1], 110 parts of Carnauba WAX, 22 parts of CCA (salicylic acid metal complex E-84: Orient Chemical Industry), and 947 parts of ethyl acetate were charged with stirring. The temperature was raised to 0 ° C., kept at 80 ° C. for 5 hours, and then cooled to 30 ° C. over 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 are 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 are 80 vol%. 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, followed by one pass 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%.

[Example 1]
(Emulsification ⇒ Solvent removal)
[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) 10% hydrochloric acid was added to the filter cake of (1) to adjust to pH 2.8, mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(3) 300 parts of ion-exchanged water was added to the filter cake of (2), mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered twice to obtain [filter cake 1]. .
[Filtration cake 1] was dried at 45 ° C. for 48 hours in a circulating drier, and sieved with a mesh of 75 μm to obtain [Toner 1].
The binder resin of [Toner 1] is 100% by weight of a polyester resin.

Production Example 8 (Synthesis of MB)
1200 parts of water, C.I. I. Pigment Red PR57: 1 (Dainippon Ink Chemical Co., Ltd.) 540 parts, modified polyurethane dispersant “EFKA-4060” (amine value: 6-10, EFKA Chemicals) 108 parts, polyester resin 1200 parts In addition, the mixture was mixed with a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.), and 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 [Masterbatch 2] was used instead of [Masterbatch 1] in Example 1.
The binder resin of [Toner 2] is 100% by weight of polyester resin.

Production Example 9 (Synthesis of MB)
1200 parts of water, C.I. I. 540 parts of Pigment Yellow PY74 (manufactured by Clariant), 108 parts of “EFKA-7462” (amine value: 6-10, EFKA Chemicals) which is a modified polyurethane dispersant, and 1200 parts of polyester resin were added, and Henschel mixer (Mitsui) (Mine Co., Ltd.) and the mixture was kneaded at 150 ° C. for 30 minutes using two rolls, then cooled by rolling 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.
The binder resin of [Toner 3] is 100% by weight of polyester resin.

[Comparative Example 1]
[Toner 4] was obtained in the same manner as in Example 1 except that the polymer dispersant “EFKA-4080” was not added.

[Comparative Example 2]
[Toner 5] was obtained in the same manner as in Example 2 except that the polymer dispersant “EFKA-4060” was not added.

[Comparative Example 3]
[Toner 6] was obtained in the same manner as in Example 3 except that the polymer dispersant “EFKA-7462” was not added.

(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 was 1.0 ± 0.1 mg / cm_ on a solid image on a plain paper and a thick paper transfer paper (Ricoh Type 6200 and NBS Ricoh Copied Printing Paper <135>) using Ricoh's imgio Neo 450. The toner was developed so that the toner was developed, and the temperature of the fixing belt was adjusted to be variable. After outputting a solid image, the image density was 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”. With a modified machine of Neo 450 "(manufactured by Ricoh), fixing was performed without fixing fuser oil, and an OHP fixed image was created.
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 40 kV. FIG. 1 is a transmission electron micrograph showing the particle structure of the toner of Example 1, and FIG. 2 is a transmission electron micrograph showing the particle structure of the toner of Comparative Example 1. In these photographs, small black dots are colorants. When FIG. 1 is compared with FIG. 2, in the toner of Comparative Example 1, a colorant aggregate is present, and a portion where no colorant is present is also observed. On the other hand, in the toner of Example 1, it was confirmed that the colorant was uniformly distributed in the toner and local aggregation of the colorant was not observed and 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. In addition, it can be seen that the coloring property and light transmittance after fixing on the OHP sheet are also excellent. Further, it can be seen that the colorant does not agglomerate during the production and the dispersion stability is good.

2 is a transmission electron micrograph showing the particle structure of the toner of Example 1. 3 is a transmission electron micrograph showing the particle structure of the toner of Comparative Example 1.

Claims (33)

  In a toner containing at least a binder resin and a colorant produced in an aqueous medium, the image is characterized in that 50 to 100% by weight of the binder resin is a polyester resin, and further contains a modified polyurethane dispersant. Toner for forming.   2. The image forming toner according to claim 1, wherein the modified polyurethane dispersant has an acid value of 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 an acid value of the colorant is 1 mgKOH / g or more and 30 mgKOH / g or less.   The image-forming toner according to claim 1, wherein the modified polyurethane-based dispersant is compatible with a binder resin.   The image-forming toner according to claim 1, wherein the modified polyurethane-based 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 modified polyurethane dispersant added is 1 part by weight or more and 50 parts by weight or less with respect to 100 parts by weight of the colorant.   The image forming toner according to claim 1, wherein the modified polyurethane dispersant is contained in the toner at a ratio of 0.1 wt% or more and 10 wt% or less.   The colorant is selected from Pigment Red PR122, PR269, PR184, PR57: 1, PR238, PR146, PR185, Pigment Yellow PY93, PY128, PY155, PY180, PY74, and Pigment Blue PB15: 3. The toner for image formation according to any one of 1 to 7.   The image forming toner according to claim 1, further comprising a release agent.   The image forming toner according to claim 9, wherein the content of the releasing agent is 1 part by weight or more and 40 parts by weight or less with respect to 100 parts by weight of the image forming toner.   The toner for image formation according to claim 9 or 10, wherein the releasing agent has a melting point of 160 ° C or lower.   The image forming toner according to claim 1, wherein the method for producing the toner in the aqueous medium is a dissolution suspension method.   The method for producing toner in the aqueous medium comprises dissolving or dispersing a modified polyester resin, a colorant, and a modified polyurethane dispersant having a site capable of reacting with a compound having at least an active hydrogen group in an organic solvent, The solution or dispersion is dispersed in an aqueous medium, and the modified polyester resin having a site capable of reacting with the compound having an active hydrogen group is reacted with the compound having an active hydrogen group or while reacting, The image forming toner according to claim 1, wherein the toner is an organic solvent is removed, washed, and dried.   The image forming toner according to claim 13, wherein resin particles are contained in the aqueous medium and are adhered to the toner surface.   The image forming toner according to claim 14, wherein the resin fine particles have an average particle diameter of 5 to 500 nm.   In the organic solvent, a non-modified polyester resin is dissolved or dispersed together with a modified polyester resin capable of reacting with a compound having an active hydrogen group, and the weight ratio of the modified polyester resin to the non-modified polyester resin is 5 / The image forming toner according to claim 13, wherein the toner is 95 to 75/25.   The image forming toner according to claim 16, wherein an acid value of the modified polyester resin and the non-modified polyester resin is 0 to 30 mg KOH / g.   An electrostatic latent image developer comprising the image forming toner according to claim 1.   18. A two-component developer for developing an electrostatic latent image, comprising the image forming toner according to claim 1 and a carrier.   In an image forming toner producing method for producing an image forming toner containing at least a binder resin and a colorant in an aqueous medium, 50 to 100% of the binder resin is a polyester resin, and a modified polyurethane as a component A method for producing a toner for image formation, comprising a system dispersant.   21. The image-forming toner according to claim 20, wherein the modified polyurethane dispersant is a modified polyurethane dispersant having an acid value of 30 mgKOH / g or less and an amine value of 1 or more and 100 or less. Method.   The toner is produced by preparing an oil phase component by dissolving or dispersing the modified polyurethane dispersant and a colorant in a binder resin, and dispersing the oil phase component in an aqueous medium. The method for producing an image forming toner according to 20 or 21.   An oil phase component is prepared by dissolving or dispersing a colorant dispersion in which the colorant is dispersed in an organic solvent in advance with at least the modified polyurethane-based dispersant in an organic solvent together with at least the binder resin. The method for producing a toner for image formation according to claim 20 or 21, wherein the toner is produced by dispersing the phase component in an aqueous medium.   The method for producing an image forming toner according to claim 23, wherein a blending ratio of the colorant and the organic solvent is in the range of 5:95 to 50:50 in the colorant dispersion.   The image forming toner according to any one of claims 20 to 24, wherein a manufacturing method of the image forming toner that generates the image forming toner containing the binder resin and the colorant in the aqueous medium is a solution suspension method. Manufacturing method.   An image forming toner manufacturing method for producing an image forming toner containing a binder resin and a colorant in the aqueous medium is a modified polyester having a site capable of reacting with a compound having at least an active hydrogen group in an organic solvent. Dissolve or disperse resin, colorant, and modified polyurethane dispersant, disperse the solution or dispersion in an aqueous medium, and activate the modified polyester resin having a site capable of reacting with the compound having an active hydrogen group. 25. The toner for image formation according to claim 20, wherein the organic solvent is removed, washed and dried after reacting with a compound having a hydrogen group or while reacting. Manufacturing method.   27. The method for producing an image forming toner according to claim 26, wherein resin fine particles are contained in the aqueous medium and are adhered to the toner surface.   28. The method for producing an image forming toner according to claim 27, wherein the resin fine particles have an average particle diameter of 5 to 500 nm.   The organic solvent contains a non-modified polyester resin together with a modified polyester resin capable of reacting with the compound having an active hydrogen group, and the weight ratio of the modified polyester resin to the non-modified polyester resin is 5/95. The method for producing an image forming toner according to any one of claims 26 to 28, wherein the toner is formed to be 75/25.   30. The method for producing an image forming toner according to claim 29, wherein an acid value of the modified polyester resin and the non-modified polyester resin is 0 to 30 mgKOH / g.   At least after charging the photoconductor, an electrostatic latent image is formed by image exposure, and the electrostatic latent image is developed with toner, and then the toner image is transferred onto the transfer body, and if necessary after transfer 18. An image forming method in which the step of cleaning the photoconductor is repeated, wherein the toner is the image forming toner according to any one of claims 1 to 17.   An image forming apparatus comprising at least a charging unit, an image exposing unit, a developing unit, a transferring unit, a fixing unit, and an electrophotographic photosensitive member, wherein the developing unit holds toner, and the toner is any one of claims 1 to 17. An image forming apparatus comprising the image forming toner according to claim 1. In a process cartridge that integrally supports at least one member selected from a photosensitive member, a charging unit, a developing unit, and a cleaning unit, and is detachable from an image forming apparatus main body, the developing unit holds toner, A process cartridge, wherein the toner is an image forming toner according to claim 1.