JP2013050606A - Yellow toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a yellow toner that suppresses exposure of a yellow pigment on a toner surface and has excellent low-temperature fixability and excellent charge stability even under a low temperature and low humidity environment.SOLUTION: A yellow toner includes a yellow pigment, a binder resin, a release agent and toner particles containing zinc phthalocyanine or zinc phthalocyanine derivative. The toner particles are obtained in an aqueous medium. In the yellow toner, if interface tension A (mN/m) between water and fluid dispersion obtained by dispersing the yellow pigment in toluene is 20 to 35 mN/m and interface tension between water and fluid dispersion obtained by dispersing the zinc phthalocyanine or the zinc phthalocyanine derivative in toluene is regarded as B (mN/m), A<B is satisfied.

Description

  The present invention relates to a yellow toner used in an image forming method such as an electrophotographic method, an electrostatic recording method, and a toner jet method.

  Conventionally, in electrophotography, generally, a photoconductive material is used, and an electrostatic charge image is formed on a photoreceptor by various means. Then, the electrostatic charge image is developed with toner, and if necessary, After the toner image is transferred to a transfer material such as paper, it is fixed by heating, pressing, heating and pressing, or solvent vapor to obtain an image.

  In an image forming apparatus employing these image forming methods, a fixing process in which a toner image transferred to a medium such as paper or an OHP (overhead projector) sheet is fixed by heat requires particularly large power consumption. Reduction of power consumption by fixing at low temperature is desired.

On the other hand, the fixing process and the melting characteristics of the toner are largely related to the image quality.
In particular, since a full-color image forming apparatus forms a color image of yellow, magenta, cyan, black or the like by superimposing a plurality of color toners on the same transfer material, the amount of toner on the transfer material is large. Therefore, in order to obtain high coloring power, high glossiness, rich color reproducibility, and high transparency of OHP, it is necessary to improve the melt color mixing property and smoothness of the fixed image.

  In general, when the fixing temperature is set low, the amount of heat of fusion of the toner becomes insufficient, the image glossiness and color reproducibility tend to decrease, and the fixed image has poor scratch resistance and peeling resistance.

  Therefore, the toner is required to melt even if it has a low heat quantity and to exhibit sufficient fixability.

  Furthermore, in recent years, in toner manufactured in an aqueous medium, particularly yellow toner, the toner particles tend to be hard because the pigment acts as a filler, and the pigment is likely to be exposed on the surface of the toner particles. For this reason, if the fixing temperature is set low, there is a problem that the toner is not sufficiently melted. There has been a demand for further improvement in low-temperature fixability overcoming this problem.

  As a means for improving the low-temperature fixability, for example, the amount of insoluble components and soluble components in the case where the solvent is different by a method of defining the average viscosity change amount of the toner (see, for example, Patent Document 1) or the Soxhlet extraction method of the toner. A defining method (see, for example, Patent Document 2) has been proposed.

  However, according to the study by the present inventors, these toners certainly improved the fixing characteristics as compared with the conventional toners. However, particularly with the yellow toner as described above, printing can be performed at a high speed in a low temperature environment. It has been found that there is room for improvement in the fixing property when a sufficient amount of heat is not applied.

  Further, a method for controlling the dispersibility of the pigment using zinc phthalocyanine (for example, see Patent Document 3) has been proposed. However, although it is possible to improve the dispersibility of the yellow pigment by this method, since the exposure of the pigment to the toner particle surface cannot be reduced, there is still room for improvement in terms of fixability.

  In addition to the demand for higher image quality, from the viewpoint of image quality, a toner having excellent heat resistance and light resistance is desired. For the purpose of improving this, a yellow pigment excellent in heat resistance and light resistance (for example, see Patent Document 4) has been proposed. However, as described above, in the yellow toner, there is a tendency that a fixing failure due to the yellow pigment being exposed on the surface of the toner particles and a charging failure due to being in the vicinity of the toner particle surface tend to occur. As a result, when a pigment that is easily triboelectrically charged is used, charge-up occurs in a low-temperature and low-humidity environment, which tends to cause a decrease in image density.

  On the other hand, in the field of color printers for personal computers and personal color copying, since the output from the Internet and personal computer screens increases, the standard color space in the field, sRGB, is well supported and wide colors. There is a need for a reproducible image forming system and toner.

  As pigments used in conventional yellow toners, C.I. I. Pigment yellow 73, C.I. I. Pigment Yellow 74 or the like was used, but there were various problems. For example, in a yellow toner manufactured in an aqueous medium, the pigment has poor dispersibility and tends to be reddish, so that the reproducibility of the yellow / red color gamut is excellent, but the reproduction in the green color gamut. Since it is inferior, the color space of sRGB has not been fully supported. Furthermore, in the sRGB standard, the lightness of green is required to be higher than magenta, and the yellow pigment is not compatible.

  Further, as a means for improving the green reproducibility in the sRGB standard, there is a method of using a dye and a pigment together (for example, refer to Patent Document 5), but further improvement in terms of image light resistance, transparency, and fixability. Is required.

JP 2007-279666 A JP 2008-129308 A JP 2003-277463 A Japanese Patent Laid-Open No. 2-208662 JP 2000-347459 A

  The problem to be solved by the present invention is to provide a yellow toner that suppresses exposure of the yellow pigment to the toner particle surface and has good low-temperature fixability, and further has excellent charging stability even in a low-temperature and low-humidity environment. That is.

  In order to achieve the above object, the present invention provides a yellow toner having a yellow pigment, a binder resin, a release agent, and toner particles containing zinc phthalocyanine or a zinc phthalocyanine derivative, wherein the toner particles are in an aqueous medium. The surface tension A (mN / m) of the dispersion obtained by dispersing the yellow pigment in toluene and water is 20 mN / m or more and 35 mN / m or less, and the zinc phthalocyanine or the zinc phthalocyanine derivative When the interfacial tension between the dispersion of water and toluene dispersed in water is B (mN / m), the relationship of A <B is satisfied.

  According to the present invention, it is possible to provide a toner having excellent low-temperature fixability, excellent charging stability even in a low-temperature and low-humidity environment, and excellent green color reproducibility by the zinc phthalocyanine or zinc phthalocyanine derivative.

FIG. 6 is an explanatory diagram of an apparatus for measuring the charge amount of toner.

  The inventors of the present invention have intensively studied a yellow toner that can provide excellent low-temperature fixability, charging stability, and color reproducibility.

  As a result, the toner particles contain zinc phthalocyanine or a zinc phthalocyanine derivative, and control the value of the interfacial tension between the yellow pigment and the zinc phthalocyanine or zinc phthalocyanine derivative dispersed in toluene and water. As a result, it was found that a yellow toner excellent in low-temperature fixability, charging stability in a low-temperature and low-humidity environment, and green color reproducibility was obtained, and the present invention was completed.

  The yellow toner of the present invention has a yellow pigment, a binder resin, a release agent, and toner particles containing zinc phthalocyanine or a zinc phthalocyanine derivative. In the yellow toner obtained in an aqueous medium, the yellow toner Dispersion in which the interfacial tension A (mN / m) between a dispersion liquid in which pigment is dispersed in toluene and water is 20 mN / m or more and 35 mN / m or less and the zinc phthalocyanine or the zinc phthalocyanine derivative is dispersed in toluene When the interfacial tension between the liquid and water is B (mN / m), the relationship of A <B is satisfied.

  The detailed mechanism by which the low-temperature fixability of yellow toner is improved by the present invention is considered as follows.

  Generally, in a toner manufactured in an aqueous medium, a toner material having high hydrophilicity tends to be distributed in the vicinity of the toner surface layer.

  Accordingly, a large amount of yellow pigment having high hydrophilicity is distributed in the vicinity of the toner surface layer, and thus more easily exposed to the toner particle surface. Further, since the pigment is cured in the toner medium as a filler and absorbs heat necessary for fixing the toner to a medium such as paper, in order to fix the toner in such a state to the medium, More heat is needed. That is, in order to achieve low-temperature fixability, further improvement was necessary for this point.

  The present inventors consider that the present invention could suppress the exposure of the yellow pigment to the toner particle surface layer.

  That is, zinc phthalocyanine or a zinc phthalocyanine derivative has a lower hydrophilicity than a yellow pigment that satisfies the above-mentioned range of interfacial tension, and therefore has a low distribution on the toner particle surface layer. In addition, since zinc, which is a central metal, is a metal that can have a five-coordinate structure or a six-coordinate structure, a yellow pigment can be adsorbed to the vacant orbit of the zinc phthalocyanine. As a result, the yellow pigment tends to be present inside the toner particles due to the presence of zinc phthalocyanine or zinc phthalocyanine derivative, and it is considered that the exposure to the toner particle surface layer is suppressed.

  The smaller the value of the interfacial tension with respect to water of the dispersion liquid in which the yellow pigment is dispersed in toluene, the more easily the interface is familiar with water, that is, the property of high hydrophilicity.

  Therefore, in the toner particles produced in an aqueous medium, when the interfacial tension of the yellow pigment satisfies the following value in the presence of the zinc phthalocyanine or the zinc phthalocyanine derivative, the distribution of the yellow pigment near the toner particle surface is It is considered appropriate.

  That is, in the present invention, the interfacial tension A (mN / m) is 20 mN / m or more and 35 mN / m or less, and when the interfacial tension is B (mN / m), A <B is satisfied. It is essential.

  When the interfacial tension A is less than 20 mN / m, the hydrophilicity of the yellow pigment is high, so that the surface layer exposure of the yellow pigment cannot be suppressed despite the interaction with zinc phthalocyanine. It is thought that the effect cannot be obtained. Further, when the value of the interfacial tension is larger than 35 mN / m, the yellow pigment tends to be present inside the toner particles because the hydrophilicity of the yellow pigment is low, and in addition, the toner particles are further enhanced by the interaction with zinc phthalocyanine. Distributed inside. As a result, uneven distribution of the pigment in the toner particles and further distribution of other toner constituent materials tend to occur. As a result, it is considered that a toner portion where heat is not easily transmitted locally is formed, and the fixing effect as described above cannot be obtained. Further, when the value of the interfacial tension does not satisfy the relationship of A <B, that is, the interfacial tension B between the dispersion obtained by dispersing zinc phthalocyanine or a zinc phthalocyanine derivative in toluene and water dispersed the yellow pigment in toluene. When the interfacial tension A between the dispersion and water is lower than the above, even if zinc phthalocyanine or zinc phthalocyanine derivative is adsorbed to the yellow pigment, the effect of suppressing the yellow pigment inside the toner cannot be obtained as described above. It is considered that such a fixing effect cannot be obtained.

  The more preferable interfacial tension A that provides the fixing effect is 20 mN / m or more and 25 mN / m or less. By setting the interfacial tension A of the yellow pigment within the above range, the exposure of the yellow pigment on the surface of the toner particles can be suppressed, and the familiarity of the yellow pigment with other materials constituting the toner is good. It is considered that the condition can be suppressed.

  In addition, the present invention can improve the decrease in image density in a low-temperature and low-humidity environment, which occurs when using a toner containing a yellow pigment having a high frictional charging ability. In this regard, the inventors consider as follows.

  Conventionally, in a yellow toner produced in an aqueous medium, the pigment tends to exist in the toner surface layer or in the vicinity of the surface layer. As a result, when a yellow pigment having a high frictional charging ability is used, the pigment existing near the toner surface tends to be charged up at low temperature and low humidity, and the image density tends to decrease.

  In the present invention, zinc phthalocyanine or a zinc phthalocyanine derivative acts on the yellow pigment, and zinc, which is a central metal, becomes a charge leakage site, thereby suppressing charge-up and improving the decrease in image density. ing.

  Further, the inventors have found that the above-described effect of improving the image density is a yellow pigment that satisfies the following conditions. That is, the effect of improving the reduction in image density can be obtained when the charged amount of the yellow pigment charged with a magnetic carrier at 15 ° C. and 10% is −35 mC / kg or more and −12 mC / kg or less.

  Moreover, the hue can be shifted to green by adding the zinc phthalocyanine or zinc phthalocyanine derivative to the yellow toner. As a result, green color reproducibility, which has been insufficient in the past, can be improved.

  In addition to controlling the interfacial tension value of yellow to the above value, the dispersibility of the yellow pigment in the toner can be controlled by adjusting the amount of the zinc phthalocyanine or zinc phthalocyanine derivative. Therefore, the saturation and transparency can be improved.

  Examples of means for adjusting the yellow pigment according to the present invention to the above-described interfacial tension include a method of subjecting the yellow pigment to a surface treatment or a method of changing the type of the yellow pigment.

  As a method for surface-treating the pigment, for example, there is a method using rosin. Specifically, the surface treatment of the pigment using rosin includes (1) a dry mixing method in which rosin and the pigment are dry mixed and then subjected to heat treatment such as melt-kneading as necessary, and (2) at the time of pigment production. Examples include wet treatment in which an aqueous solution of rosin is added to the pigment synthesis solution, and then a lake metal salt such as calcium, barium, strontium, or manganese is added to insolubilize the rosin to coat the pigment surface. It is done.

  As the yellow pigment used in the yellow toner of the present invention, it is possible to adjust the interfacial tension by using the above-mentioned means. Therefore, it is possible to use a commercially available yellow pigment. In particular, C.I. I. Pigment Yellow 62, 73, 74, 83, 93, 94, 95, 109, 110, 111, 120, 128, 129, 147, 151, 154, 155, 166, 167, 168, 180, 185, 191 and 199, etc. Is mentioned. Further, from the viewpoint of further improvement in low-temperature fixability and green color reproduction, C.I. I. Pigment Yellow, 155 are preferable.

  Zinc phthalocyanine used in the present invention is represented by the following structural formula (1).

(Wherein R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, an alkylene group or an alkoxy group, and may be the same or different. N is 1 or 2) .)
Moreover, a well-known thing can be used as a zinc phthalocyanine derivative. For example, those having functional groups such as carboxylic acid and sulfonic acid introduced into four isoindole sites, and those having other substituents such as aromatic groups, aliphatic groups, ether groups and alcohol groups introduced. It is done. However, functional groups that can themselves be ligands such as amine groups and side chains that are sterically hindered on the adsorption surface with the pigment are not preferred.

  Regarding the content of zinc phthalocyanine represented by the structural formula (1), it is preferable that zinc phthalocyanine is contained in an amount of 0.1% by mass to 10% by mass with respect to the yellow pigment.

  By being in the said range, the effect of zinc phthalocyanine and a yellow pigment is strong, and also low-temperature fixability is improved.

In the present invention, the hue angle h ^* of the yellow toner according to the L ^* a ^* b ^* color system is preferably 95 ° or more and 110 ° or less. The hue angle is defined by a straight line connecting a hue (a ^* , b ^* ) of an image having a toner adhesion amount on paper of 0.50 mg / cm ² and an origin, and a positive a ^* axis in a ^* −b ^* coordinates. There is an angle formed, in the positive a ^* from the axis of the counter-clockwise direction, which is the straight line and the positive a ^* angle between axes.

  When the hue angle is within the above range, the reproducibility of the green hue combining the yellow toner of the present invention and the conventional cyan toner is improved, and a green image with high saturation is obtained.

  Furthermore, it has been found that the difference between the hue on the OHT and the hue on the paper can be reduced by setting the hue angle of the toner of the present invention within the above range.

  The method for producing the toner of the present invention is preferably a suspension polymerization method or an emulsion polymerization method, more preferably a toner is produced by a suspension polymerization method.

  A method for producing toner particles by suspension polymerization will be described. The polymerizable monomer, colorant, mold release agent, polar resin, charge control agent and other additives as required are uniformly distributed by a disperser such as a homogenizer, a ball mill, a colloid mill, or an ultrasonic disperser. Dissolve or disperse. A polymerization initiator is dissolved in this, and a polymerizable monomer composition is prepared. Next, the polymerizable monomer composition is dispersed in an aqueous medium containing a dispersion stabilizer to form particles (granulation), and the polymerizable monomer in the particles is polymerized to produce toner particles. To do. The polymerization initiator may be added at the same time when other additives are added to the polymerizable monomer, or may be mixed immediately before the polymerizable monomer composition is dispersed in the aqueous medium. . Also, a polymerization initiator dissolved in a polymerizable monomer or solvent can be added immediately after granulation and before starting the polymerization reaction.

  When a toner is produced by the above suspension polymerization method, the polar resin and the charge control resin are uniformly transferred to the vicinity of the toner particle surface, and the particle surface is uniformly covered with the dispersant by attracting with the dispersant in water. It prevents coalescence of toner particles, exhibits excellent granulation stability, and brings about a favorable effect in terms of production. Furthermore, since the toner particles can be produced in a more spherical shape, the transferability is improved.

  Examples of the binder resin used in the toner of the present invention include commonly used styrene-acrylic copolymers, styrene-methacrylic copolymers, epoxy resins, and styrene-butadiene copolymers. As the polymerizable monomer constituting the binder resin, a vinyl polymerizable monomer capable of radical polymerization can be used. As the vinyl polymerizable monomer, a monofunctional polymerizable monomer or a polyfunctional polymerizable monomer can be used.

  The following are mentioned as a polymerizable monomer for producing | generating a binder resin. Styrene; Styrenic monomers such as o- (m-, p-) methylstyrene, m- (p-) ethylstyrene; methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, Propyl methacrylate, butyl acrylate, butyl methacrylate, octyl acrylate, octyl methacrylate, dodecyl acrylate, dodecyl methacrylate, stearyl acrylate, stearyl methacrylate, behenyl acrylate, behenyl methacrylate, 2-ethylhexyl acrylate, Acrylic acid ester monomers such as 2-ethylhexyl methacrylate, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate and diethylaminoethyl methacrylate, Ether-based monomers; butadiene, isoprene, cyclohexene, acrylonitrile, methacrylonitrile, acrylic acid amide, such as ene-based monomers methacrylamide.

  In the present invention, a crosslinking agent may be used when the binder resin is synthesized in order to increase the mechanical strength of the toner particles.

  Examples of the bifunctional crosslinking agent include the following. Divinylbenzene, bis (4-acryloxypolyethoxyphenyl) propane, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6 -Hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 200, # 400, # 600 diacrylate, dipropylene glycol diacrylate, polypropylene Glycol diacrylate, polyester-type diacrylate (MANDA Nippon Kayaku), and dimethacrylate instead of diacrylate Thing.

  The following are mentioned as a polyfunctional crosslinking agent. Pentaerythritol triacrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, tetramethylol methane tetraacrylate, oligoester acrylate and its methacrylate, 2,2-bis (4-methacryloxypolyethoxyphenyl) propane, diallyl phthalate, tri Allyl cyanurate, triallyl isocyanurate and triallyl trimellitate. The addition amount of these crosslinking agents is preferably 0.05 parts by weight or more and 3.00 parts by weight or less, more preferably 0.10 parts by weight or more and 1.50 parts by weight with respect to 100.00 parts by weight of the polymerizable monomer. It is below mass parts.

  Examples of the release agent that can be used in the toner of the present invention include the following. Petroleum wax such as paraffin wax, microcrystalline wax, petrolatum and derivatives thereof, montan wax and derivatives thereof, hydrocarbon wax and derivatives thereof according to Fischer-Tropsch method, polyolefin wax and derivatives thereof such as polyethylene and polypropylene, carnauba wax, candelilla Natural waxes such as waxes and derivatives thereof (the derivatives include oxides, block copolymers with vinyl monomers, and graft modified products), ester waxes, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, Animal wax, silicone wax. These waxes are used alone or in combination of two or more.

Among these, ester waxes are preferable because filming on the developing roller in durability under a low temperature and low humidity environment is improved. In particular, the maximum endothermic peak temperature is preferably 70 ° C. or higher in the DSC curve at the time of temperature rise measured by a differential scanning calorific value (DSC) measuring device.
The inventors consider the detailed mechanism as follows.

  That is, in a toner manufactured in an aqueous medium, the ester site of the ester wax acts with zinc which is the central metal of zinc phthalocyanine. Furthermore, since zinc phthalocyanine has low hydrophilicity, the wax is likely to be present inside the toner, and exposure to the toner surface is suppressed. Therefore, the wax is firmly encapsulated in the toner. As a result, it is considered that contamination on the developing roller is suppressed and filming is improved. Further, it is considered that the above-mentioned effects are particularly remarkable when the maximum endothermic peak temperature is 70 ° C. or higher.

  In the toner of the present invention, a charge control agent can be mixed with toner particles and used as necessary. By adding a charge control agent, the charge characteristics can be stabilized, and the optimum triboelectric charge amount can be controlled according to the development system.

  As the charge control agent, a known one can be used, and a charge control agent that has a high charging speed and can stably maintain a constant charge amount is particularly preferable. Further, when the toner particles are produced by a direct polymerization method, a charge control agent having a low polymerization inhibition property and substantially free from a solubilized product in an aqueous medium is particularly preferable.

  Examples of the charge control agent that control the toner to be negatively charged include the following. Organic metal compounds and chelate compounds are effective, and monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids, and dicarboxylic acid-based metal compounds. Other examples include aromatic oxycarboxylic acids, aromatic mono- and polycarboxylic acids and metal salts thereof, anhydrides, esters, and phenol derivatives such as bisphenol. Further examples include urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, boron compounds, quaternary ammonium salts, calixarene, and resin charge control agents.

  Examples of the charge control agent that controls the toner to be positively charged include the following. Nigrosine-modified products such as nigrosine and fatty acid metal salts; guanidine compounds; imidazole compounds; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and the like Onium salts such as phosphonium salts and lake pigments thereof; triphenylmethane dyes and lake pigments thereof. Gallic acid, ferricyanide, ferrocyanide, etc.); metal salt of higher fatty acid; resin charge control agent.

The toner of the present invention can contain these charge control agents alone or in combination of two or more.
The preferred blending amount of the charge control agent is 0.1 parts by mass or more and 20.0 parts by mass or less, more preferably 0.5 parts by mass or more and 10.0 parts by mass or less with respect to 100.0 parts by mass of the polymerizable monomer. It is. However, it is not essential to add a charge control agent to the toner of the present invention, and it is not always necessary to include the charge control agent in the toner by actively utilizing frictional charging with the toner regulating member and the developing roller. .

  The following are mentioned as a polymerization initiator used for the toner of the present invention. 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis Azo or diazo polymerization initiators such as -4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl Peroxide-based polymerization initiators such as peroxide, lauroyl peroxide, TERT-butyl-peroxypivalate.

  Although the usage-amount of these polymerization initiators changes with the target degree of polymerization, generally it is 3 to 20 mass parts with respect to 100 mass parts of polymerizable monomers. The type of the polymerization initiator is slightly different depending on the polymerization method, but is used alone or in combination with reference to the 10-hour half-life temperature.

  Examples of the polar resin in the present invention include styrene-based copolymers, maleic acid copolymers, saturated polyester resins, and unsaturated polyester resins. More preferable examples include saturated and unsaturated polyester resins. Since the polyester resin tends to be separated into layers as the polymerization proceeds in a dispersoid oil droplet mainly composed of styrene or an acrylate monomer, a stable outermost shell layer is formed. Formation of a uniform shell layer is excellent in durability.

  The alcohol component and acid component which comprise the said polyester resin are illustrated below. As alcohol components, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexane Diol, neopentyl glycol, 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexenedimethanol, hydrogenated bisphenol A, and bisphenol derivatives represented by the following general formula (A):

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10.)
Alternatively, a hydrogenated product of the compound of structural formula A, a diol represented by the following general formula (B),

Or the diol of the hydrogenated product of the compound of Formula B, Furthermore, polyhydric alcohol like glycerin, pentaerythritol, sorbit, sorbitan, the oxyalkylene ether of a novolak-type phenol resin, etc. are mentioned.

  Examples of the divalent carboxylic acid include the following. Benzene dicarboxylic acid such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride or its anhydride, alkyl dicarboxylic acid such as succinic acid, adipic acid, sebacic acid, azelaic acid or its anhydride, and further 6 to 18 carbon atoms. Succinic acid substituted with alkyl or alkenyl groups or anhydrides thereof, unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, itaconic acid or anhydrides thereof, trimellitic acid, pyromellitic acid, 1 , 2,3,4-butanetetracarboxylic acid, polyvalent carboxylic acids such as benzophenone tetracarboxylic acid and their anhydrides.

  In the present invention, the content of the polar resin is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. When the polar resin is contained in an amount of 1 part by mass or more, a uniform shell layer can be formed. Moreover, when it contains within 20 mass parts, generation | occurrence | production of an emulsified particle etc. will be suppressed and the stable developability can be shown.

  In the present invention, as the dispersion stabilizer used at the time of preparing the aqueous medium, known inorganic and organic dispersion stabilizers can be used.

  Specifically, the following are mentioned as an example of an inorganic dispersion stabilizer. Tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, magnesium carbonate, calcium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina . Examples of the organic dispersant include the following. Polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, carboxymethyl cellulose sodium salt, starch.

  Commercially available nonionic, anionic and cationic surfactants can also be used. Examples of such surfactants include the following. Sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, calcium oleate.

  As the dispersion stabilizer used in preparing the aqueous medium used in the toner of the present invention, an inorganic poorly water-soluble dispersion stabilizer is preferable, and it is preferable to use a poorly water-soluble inorganic dispersion stabilizer that is soluble in acid. .

  Moreover, in this invention, when preparing an aqueous medium, the usage-amount of these dispersion stabilizers is 0.2 to 20.0 mass parts with respect to 100.0 mass parts of polymerizable monomers. It is preferable that Moreover, in this invention, it is preferable to prepare an aqueous medium using 300 to 3000 mass parts of water with respect to 100 mass parts of polymerizable monomer compositions.

When preparing an aqueous medium in which the above dispersion stabilizer is dispersed, a commercially available dispersion stabilizer may be used as it is. In order to obtain particles of a dispersion stabilizer having a fine uniform particle size, an aqueous medium may be prepared by generating a dispersion stabilizer in a liquid medium such as water under high-speed stirring. For example, when tricalcium phosphate is used as a dispersion stabilizer, a preferred dispersion stabilizer can be obtained by mixing sodium phosphate aqueous solution and calcium chloride aqueous solution under high speed stirring to form fine particles of tricalcium phosphate. Can do.
The toner of the present invention is preferably a toner having toner particles and an external additive such as an inorganic fine powder.

  Examples of the inorganic fine powder include fine powder such as silica fine powder, titanium oxide fine powder, alumina fine powder, and double oxide fine powder thereof. Among the inorganic fine powders, silica fine powder and titanium oxide fine powder are preferable. Examples of external additives other than inorganic fine powders include various resin particles and fatty acid metal salts. These are preferably used alone or in combination.

Examples of the silica fine powder include dry silica or fumed silica produced by vapor phase oxidation of silicon halide, wet silica produced from water glass, sol-gel silica produced by a sol-gel method, and the like. As the inorganic fine powder, dry silica having less silanol groups on the surface and inside the silica fine powder and less NA ₂ O and SO ₃ ²⁻ is preferable. The dry silica may be a composite fine powder of silica and another metal oxide produced by using a metal halogen compound such as aluminum chloride or titanium chloride together with a silicon halogen compound in the production process.

  Since the inorganic fine powder can be hydrophobized to adjust the charge amount of the toner, improve the environmental stability, and improve the characteristics in a high-humidity environment, use the hydrophobized inorganic fine powder. Is preferred. If the inorganic fine powder added to the toner is difficult to absorb moisture, a decrease in the charge amount as the toner tends to be reduced, and the developability and transferability tend to be improved.

  Non-modified silicone varnishes, various modified silicone varnishes, unmodified silicone oils, various modified silicone oils, silane compounds, silane coupling agents, other organosilicon compounds, and organotitanium compounds are used as hydrophobic treatment agents for inorganic fine powders. Can be mentioned. These treatment agents may be used alone or in combination.

Among these, inorganic fine powder treated with silicone oil is preferable. More preferably, a hydrophobic treated inorganic fine powder treated with a silicone oil at the same time as or after the hydrophobic treatment of the inorganic fine powder with a coupling agent is excellent in environmental characteristics.
Hereinafter, various measurement methods according to the present invention will be described.

<Interfacial tension measurement>
The interfacial tension in the present invention was measured by the hanging drop method described below.
Specifically, using a FACE solid-liquid interface analyzer Drop Master 700 manufactured by Kyowa Interface Science Co., Ltd. in an environment at a temperature of 25 ° C., measurement was performed with WIDE 1 as the field of view of the lens portion. First, the tip of a fishing hook, which is a thin tube having an inner diameter of 0.4 mm, is put into ion exchange water. Next, the thin tube is connected to the syringe part. The toluene dispersion of the sample to be measured is put in the syringe part in a degassed state. In the measurement method of the present invention, the sample concentration dispersed in toluene was 0.99% by mass. Next, the syringe part is connected to an AUTO DISPENSER AD-31 manufactured by Kyowa Interface Science Co., Ltd., and the toluene dispersion is pushed out from the capillary tube, whereby a droplet can be created at the tip of the capillary tube in the ion exchange water. Then, the interfacial tension with water is calculated from the shape of the droplet. The control and calculation method for creating droplets was performed using a measurement analysis system manufactured by Kyowa Interface Science Co., Ltd. The density difference between water and toluene dispersion required for the calculation was 0.13 g / cm ³ , which is the density difference between water and toluene. The final measurement result of the interfacial tension was the average value of 10 measurements.

<Measurement of weight average particle diameter (D4)>
The weight average particle diameter (D4) of the toner is calculated as follows. As a measuring device, a precision particle size distribution measuring device “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) using a pore electrical resistance method is used. For setting the measurement conditions and analyzing the measurement data, the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) is used. The measurement is performed with 25,000 effective measurement channels.

  As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

Prior to measurement and analysis, the dedicated software was set as follows.
In the screen for changing the standard measurement method (SOM) of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements once, and the Kd value is “standard particles 10.0 μm” (manufactured by Beckman Coulter) Set the value obtained using. The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.

  In the special software pulse to particle size conversion setting screen, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

The specific measurement method is as follows.
(1) About 200 ml of the electrolytic solution is placed in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, the dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the dedicated software.
(2) About 30 ml of the electrolytic aqueous solution is put into a glass 100 ml flat bottom beaker. In this, "Contaminone N" (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH7 precision measuring instrument cleaning, made by organic builder, manufactured by Wako Pure Chemical Industries, Ltd. About 0.3 ml of a diluted solution obtained by diluting 3) with ion-exchanged water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated with the phase shifted by 180 degrees, and an ultrasonic disperser “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikki Bios Co., Ltd.) having an electrical output of 120 W is prepared. A predetermined amount of ion-exchanged water is placed in a water tank of an ultrasonic disperser, and about 2 ml of the contamination N is added to the water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
(5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
(6) To the round bottom beaker of (1) installed in the sample stand, the electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette, and the measurement concentration is adjusted to about 5%. . Measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement data is analyzed with the dedicated software attached to the apparatus, and the weight average particle diameter (D4) is calculated. The “average diameter” on the analysis / volume statistics (arithmetic average) screen when the graph / volume% is set with the dedicated software is the weight average particle diameter (D4).

<Measurement of hue of image>
The toner hue is a solid image in which the amount of toner applied is 0.50 mg / cm ² using the image forming apparatus described in the example (modified machine of LBP7700C (manufactured by Canon Inc.)). Then, a ^* and b ^* (a ^* and b ^* are chromaticities indicating hue and saturation) of the image were measured. A spectrocolorimeter type 938 manufactured by X-Rite was used as the measuring device, the observation light source was a C light source, and the viewing angle was 2 °. The hue angle was determined from the obtained a ^* and b ^* .

<Measurement of charge amount of yellow pigment>
The charge amount of the yellow pigment was obtained by mixing 99.5 parts by mass of a magnetic carrier (Standard Carrier For q / m Measurement N-01, manufactured by Nippon Imaging Co., Ltd.) with respect to 0.5 parts by mass of the yellow pigment. After being allowed to stand in a 10% environment for 24 hours, after shaking for 3 minutes at 150 rpm with a YS-8D model manufactured by YAYOI, the measurement was performed as follows.

FIG. 1 is an explanatory diagram of a charge amount measuring apparatus for measuring the charge amount of a yellow pigment. First, about 0.4 g of a mixture of a pigment and a carrier whose charge is to be measured is placed in a metal measuring container 102 having a 500 mesh screen 103 at the bottom, and a metal lid 104 is formed. At this time, the weight of the entire measurement container 102 is weighed, and the value is defined as W ₁ (g). Next, in the suction machine 101 (at least the insulator is in contact with the measurement container 102), suction is performed from the suction port, and the air volume control valve 106 is adjusted to set the pressure of the vacuum gauge 105 to 250 mmAq. In this state, the toner is removed by suction for 2 minutes. The potential of the electrometer 109 at this time is set to V (volt). Here, reference numeral 108 denotes a capacitor having a capacity C (μF). Next, the weight of the entire measurement container after suction is weighed and is defined as W ₂ (g). The charge amount (mC / kg) of this pigment is calculated by the following equation using the value measured above. The measurement results are shown in Table 1.

  The present invention will be specifically described with reference to the following examples. However, this does not limit the present invention in any way. In the examples and comparative examples, all parts and% are based on mass unless otherwise specified.

The colorant used in the examples will be described below. In Table 1, PY is C.I. I. It means Pigment Yellow. Further, the interfacial tension between the dispersion obtained by dispersing zinc phthalocyanine used in Examples in toluene and water was 36 mN / m.
<Yellow Pigments 1 to 5 and Comparative Yellow Pigment 1>
For yellow pigments 1 to 5, commercially available yellow pigments were used as they were without surface treatment. Yellow pigment 1 is C.I. I. Pigment Yellow 155 (manufactured by Clariant), yellow pigment 2 is C.I. I. Pigment yellow 93 (manufactured by BASF), yellow pigment 3 is C.I. I. Pigment Yellow 128 (manufactured by BASF), Yellow Pigment 4 is C.I. I. Pigment Yellow 180 (manufactured by Clariant), yellow pigment 5 is C.I. I. Pigment Yellow 185 (manufactured by BASF), and the yellow pigment 1 for comparison is C.I. I. Pigment Yellow 74 (manufactured by Sanyo Dye).

<Yellow Pigment 6>
・ Ion-exchanged water 1500 parts by mass I. Pigment Yellow 185 (manufactured by BASF) 97.0 parts by mass

  The above materials are stirred and mixed, and C.I. I. Pigment Yellow 185 was suspended in water. Thereafter, 3.0 parts by mass of rosin (acid value: 130) and 30 parts by mass of 33% strength aqueous sodium hydroxide solution were added. After raising the liquid temperature to 98 ° C., the mixture was stirred for 1 hour while maintaining the temperature. After the temperature was lowered to 65 ° C., about 60 parts by mass of 31% strength hydrochloric acid was added to precipitate the resin. The precipitated composition was filtered off, washed with ion exchange water and then dried to obtain yellow pigment 6. The values of the interfacial tension and the charge amount of the yellow pigment 6 are shown in Table 1.

<Yellow Pigment 7>
In the method for producing yellow pigment 6, the amount of rosin added is 10.0 parts by mass and the pigment is C.I. I. A yellow pigment 7 was obtained in the same manner except that the pigment yellow 74 was changed to 90.0 parts by mass. Table 1 shows the interfacial tension value and the charge amount of the yellow pigment 7.

<Yellow Pigment 8>
In the method for producing yellow pigment 6, the pigment is C.I. I. A yellow pigment 8 was obtained in the same manner except that the pigment yellow 74 was used. The values of the interfacial tension and the charge amount of the yellow pigment 8 are shown in Table 1.

<Yellow Pigment 9>
In the method for producing yellow pigment 6, the pigment is C.I. I. A yellow pigment 9 was obtained in the same manner except that the pigment yellow 155 was used. Table 1 shows the values of the interfacial tension and the charge amount of the yellow pigment 9.

<Comparison Yellow Pigment 2>
In the method for producing yellow pigment 6, the amount of rosin added was 8.0 parts by mass and C.I. I. A yellow pigment 2 for comparison was obtained by the same method except that the amount of pigment yellow 155 was changed to 92.0 parts by mass. Table 1 shows the values of the interfacial tension and the charge amount of the comparative yellow pigment 2.

<Toner Production Example 1>
Behenyl behenate (melting point 71 ° C.) 10.0 parts by mass and styrene 20.0 parts by mass were heated to 70 ° C. and stirred with a disper for 15 minutes. Next, this dispersion was dispersed using a homogenizer (15-M-8PA type Gorin Co., Ltd.) under the conditions of high-pressure shear 70 ° C. and 4900 kPa (50 kg / cm ² ) to obtain a wax dispersion.

next,
-Styrene 30.0 parts by mass-Yellow pigment 1 6.0 parts by mass-Zinc phthalocyanine (manufactured by Dainichi Seika Co., Ltd.) 0.060 parts by mass-Charge control agent (Bontron E-88; manufactured by Orient Chemical Co., Ltd.) 1.0 part by mass Part The above material was dispersed for 3 hours by Attritor (Mitsui Mining Co., Ltd.) to prepare a pigment dispersion composition.

Moreover, the following material was melt | dissolved with the propeller type stirring apparatus with another container, and the resin solution was prepared.
Styrene 20.0 parts by mass N-butyl acrylate 30.0 parts by mass Polyester resin (Acid value: 8.0 mg KOH / g, weight average molecular weight (Mw): 9,500)
5.0 parts by mass Further, 900 parts by mass of ion-exchanged water heated to 60 ° C. and 2.5 parts by mass of calcium phosphate were added to the flask, and the mixture was added at 10,000 rpm using a TK homomixer (Special Machine Industries). Stirring to obtain an aqueous medium.

Next, the pigment dispersion composition, the resin solution, and the wax dispersion were charged into a beaker, heated to 60 ° C., and dispersed and mixed for 30 minutes to obtain dispersion A. Further, the dispersion In A, 8.0 parts by mass of a polymerization initiator 2,2′-azobis (2,4-dimethylvaleronitrile) was dissolved to prepare a polymerizable monomer composition. The polymerizable monomer composition is charged into the aqueous medium, and stirred at 10,000 rpm for 15 minutes with a TK homomixer (Special Machine Industries) at a temperature of 60 ° C. in a nitrogen atmosphere. After granulating the mass composition, the temperature was raised to 70 ° C. while stirring with a paddle stirring blade. After reacting for 5 hours, the temperature was further raised to 80 ° C. and reacted for 3 hours. After cooling, hydrochloric acid was added to adjust the pH to 1.4 and stirred for 3 hours. The toner particles were separated by filtration, washed with water, and dried at a temperature of 40 ° C. for 48 hours to obtain toner particles A.

  For toner particles A (100.0 parts by mass), 1.5 parts by mass of hydrophobic silica fine powder (number average primary particle size: 16 nm) surface-treated with dimethyl silicone oil was added using a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.). The toner (A) was obtained by dry mixing for 10 minutes. Table 2 shows various physical properties of the toner (A).

<Toner Production Examples 2 to 7, 9 to 23, and Comparative Toner Production Examples 1 to 3 and 5>
In Toner Production Example 1, toners (B) to (B) were prepared in the same manner as in Toner Production Example 1, except that the colorant to be added, the type of wax, and the content of zinc phthalocyanine were changed to the compositions shown in Table 2. (G), (I) to (W), and comparative toners (a) to (c) and (e) were produced. In Comparative toner production example 5, copper phthalocyanine (manufactured by Dainichi Seika Co., Ltd.) was used instead of zinc phthalocyanine. Table 2 shows the materials and characteristics and physical properties of the obtained toner.

<Toner Production Example 8>
A mixture of the following monomers / aqueous emulsifier solution was added over 5 hours from the start of polymerization, and an aqueous initiator solution was added over 6 hours from the start of polymerization, and the mixture was further maintained for 30 minutes.

[Monomers]
-Styrene 80.0 parts by mass-Butyl acrylate 20.0 parts by mass-Acrylic acid 3.0 parts by mass-Bromotrichloromethane 0.5 parts by mass-2-mercaptoethanol 0.01 parts by mass-Divinylbenzene 0.15 parts by mass Part

[Emulsifier aqueous solution]
・ 10% sodium dodecylbenzenesulfonate 4.0 parts by mass ・ Demineralized water 100.0 parts by mass

[Initiator aqueous solution]
8% hydrogen peroxide aqueous solution 9.0 parts by mass 8% ascorbic acid aqueous solution 9.0 parts by mass After completion of the polymerization reaction, a polymer fine particle dispersion A was obtained.

  Further, a mixture of the following monomers / emulsifier aqueous solution was added over 5 hours from the start of polymerization and an initiator aqueous solution was added over 6 hours from the start of polymerization, and the mixture was further maintained for 30 minutes.

[Monomers]
-Styrene 80.0 parts by mass-Butyl acrylate 20.0 parts by mass-Acrylic acid 3.0 parts by mass-Bromotrichloromethane 0.5 parts by mass-2-mercaptoethanol 0.01 parts by mass-Divinylbenzene 0.80 parts by mass Part

[Emulsifier aqueous solution]
・ 10% sodium dodecylbenzenesulfonate 4.0 parts by mass ・ Demineralized water 100.0 parts by mass

[Initiator aqueous solution]
-8% hydrogen peroxide aqueous solution 9.0 parts by mass-8% ascorbic acid aqueous solution 9.0 parts by mass After completion of the polymerization reaction, the mixture was cooled to prepare polymer fine particles B.

(Preparation of wax dispersant)
Behenyl behenate (melting point: 71 ° C.) 25.0 parts by mass, anionic surfactant (Neogen SC Daiichi Kogyo Seiyaku Co., Ltd.) 2.5 parts by mass, demineralized water 100.0 parts by mass heated to 100 ° C. Stir for minutes. Subsequently, this dispersion was emulsified using a homogenizer (15-M-8PA type manufactured by Gorin Co., Ltd.) under the conditions of high pressure shearing 105 ° C. and 4900 kPa (50 kg / cm ² ) to obtain a wax dispersion.

(Preparation of colorant fine particle dispersion)
To 100.0 parts by mass of demineralized water, 25.0 parts by mass of yellow pigment 4 and 6.0 parts by mass of polyoxyethylene nonylphenyl ether were added and dispersed with a ball mill to obtain a yellow colorant fine particle dispersion.

(Preparation of charge control agent fine particle dispersion)
Charge control agent 4,4′-methylenebis [2- [N- (4-chlorophenyl) amido] -3-hydroxynaphthalene] 25.0 parts by mass and 10% by mass of demineralized water and alkylnaphthalenesulfonate 5 Dispersion was performed with a ball mill in the presence of 0.0 part by mass to obtain a charge control agent fine particle dispersion.

next,
Polymer fine particle dispersion A 410.0 parts by mass (as solid content)
-Colorant fine particle dispersion 40.0 parts by mass (as solid content)
・ 1.0 parts by weight of charge control agent fine particle dispersion (as solid content)
The above was put into a reaction vessel for coagulation aging equipped with a stirrer, a cooling tube and a thermometer and stirred. The mixed solution was adjusted to pH = 5.1 using 1.0 mol / liter-potassium hydroxide aqueous solution.

  As a flocculant, 180.0 parts by mass of a 20.0% sodium chloride aqueous solution is dropped into the above mixed solution over 20 minutes, and the reaction vessel is heated to 50 ° C. with stirring in an oil bath for heating. Hold for hours. The temperature was further raised to 55 ° C. and held for 1 hour to obtain an aggregate A dispersion of polymer fine particles A, colorant fine particles and charge control agent fine particles.

  75.0 parts by mass (as a solid content) of wax dispersion is added to the above Agglomerate A dispersion, and 500.0 parts by mass of a 20.0% sodium chloride aqueous solution is added dropwise as an aggregating agent to disperse Aggregate B. A liquid was obtained.

  Further, 50.0 parts by mass of polymer fine particle B dispersion (as solid content) was added to the above-mentioned aggregate B dispersion, and 500.0 parts by mass of 20.0% sodium chloride aqueous solution was added dropwise as an aggregating agent. An aggregate C dispersion was obtained.

  Finally, 35.0 parts by mass (as a solid content) of polymer fine particle B dispersion is added to the above-mentioned aggregate C dispersion, and 500.0 parts by mass of a 20.0% aqueous sodium chloride solution is added dropwise as an aggregating agent. An aggregate D dispersion was obtained. After adding 5.0 parts by mass of an anionic surfactant (Daiichi Kogyo Seiyaku: Neogen SC), the reaction vessel was sealed and heated to 95 ° C. while continuing to stir using a magnetic seal. Held for hours. The slurry was cooled, washed with an amount of water 10 times that of the slurry, and dried to obtain toner particles (H).

  With respect to 100.0 parts by mass of toner particles (H), 1.5 parts by mass (number average primary particle size: 16 nm) of hydrophobic silica fine powder surface-treated with dimethyl silicone oil was used with a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.). The toner (H) was obtained by dry mixing for 10 minutes. Table 2 shows various physical properties of the toner (H).

<Toner Production Example 24>
Use a cyan pigment (CI Pigment Blue 15: 3) instead of a yellow pigment as a colorant, do not use zinc phthalocyanine, the type of wax, and the weight average particle diameter D4 of the toner. In the same manner as in Toner Production Example 1, a toner (X) that is a cyan toner was obtained. Table 2 shows the physical properties of the obtained toner.

<Production Example 4 for Comparative Toner>
(Production example of n-electron donating compound)
A styrene- (4-vinylpyridine) copolymer was synthesized by the method shown below.

  250 ml of tetrahydrofuran was charged into a 1 liter reaction vessel, and the temperature of tetrahydrofuran was 68 ° C. Next, a mixed solution of 70 g of styrene, 3 g of 4-vinylpyridine, 6.15 g of 2,2-azoisobutyronitrile and 80 ml of tetrahydrofuran was prepared, and the mixed solution was dropped into the reaction vessel over 2 hours. After the dropwise addition, the mixture was refluxed at 68 ° C. for 4 hours. This was cooled to room temperature and 1 liter of methanol was added. The precipitated crystals were filtered, washed with methanol and washed with water. The obtained powder was dried under reduced pressure at a temperature of 30 ° C. for 24 hours to obtain 16.3 g of a styrene- (4-vinylpyridine) copolymer. When the obtained styrene- (4-vinylpyridine) copolymer was subjected to molecular weight measurement, it was found that the number average molecular weight (Mn) was 2040 and the weight average molecular weight (Mw) was 4470.

  A comparative toner (d) was obtained in the same manner as the comparative toner (b) except that the copolymer was added during the production of the pigment dispersion composition. Table 2 shows the materials and characteristics and physical properties of the obtained toner.

（※１：亜鉛フタロシアニンの代わりに銅フタロシアニンを使用）
（Ｄ４はトナーの重量平均粒径（μｍ）を表す。ｈ^＊は色相角（°）を表す。）

(* 1: Use copper phthalocyanine instead of zinc phthalocyanine)
(D4 represents the weight average particle diameter (μm) of the toner. H ^* represents the hue angle (°).)

[Example 1]
An evaluation method will be specifically described for the toner (A).
Use a modified LBP7700C (manufactured by Canon Inc.) as an evaluation machine (by changing the gear and software of the evaluation machine main body so that the process speed is 290 mm / sec), and use toner (A) on the cartridge. Refilled. In a low-temperature and low-humidity environment (15 ° C., 10% RH), low-temperature fixability, image density, filming, green color tone, OHP transparency, and color difference between images on OHT and paper were evaluated.

(1) Evaluation of low-temperature fixability (rubbing test)
A Business 4200 (weighing 105 g / m ² , manufactured by Xerox) was used as an evaluation paper, and a solid image with a toner loading of 0.50 mg / cm ² was passed through a fixing device adjusted to 180 ° C., and a load of 4.9 Kpa. Apply a soft thin paper (for example, “Dasper”, manufactured by Ozu Sangyo Co., Ltd.) to rub the fixed image obtained 5 times, and calculate the image density reduction rate (%) using the following formula. The low-temperature fixability was evaluated. The image density was measured with a color reflection densitometer (X-Rite 404A: manufactured by X-Rite Co.).
Density reduction rate = (image density before rubbing−image density after rubbing) × 100 / image density before rubbing A: less than 10% B: 10% or more, less than 15% C: 15% or more, 20% Less than D: 20% or more

(2) Evaluation of low-temperature fixability (tape peel test)
A solid image with a toner loading of 0.50 mg / cm ² is passed through a fixing device whose temperature is adjusted to 170 ° C., a polyester tape is applied on the fixed image, and a load of 4.9 Kpa is similarly applied from above. The film was rubbed with sylbon paper, and then the tape was peeled off. Evaluation was based on the reduction rate (%) of the image density before and after the tape was peeled off. The image density was measured with a color reflection densitometer (X-Rite 404A: manufactured by X-Rite Co.).
A: Less than 15% B: 15% or more, less than 20% C: 20% or more, less than 25% D: 25% or more

(3) Evaluation of image density Using a modified machine of the above-mentioned LBP7700C (manufactured by Canon Inc.), using a Business 4200 (weighing 105 g / m ² , manufactured by Xerox Corp.) in a low temperature and low humidity environment (15 ° C., 10%), The image density after printing 8,000 images with a printing ratio of 5% was evaluated. The image density was measured with a color reflection densitometer (X-Rite 404A: manufactured by X-Rite Co.).
A: 1.35 or more B: 1.30 or more, less than 1.35 C: 1.25 or more, less than 1.30 D: 1.25 or less

(4) Evaluation of filming of developing roller After printing 8,000 images with a printing ratio of 5% from the initial stage, five yellow solid images were continuously copied, and the number of white streaks was counted and the image was counted. The average number per sheet was calculated and evaluated according to the following evaluation criteria.
A: None at all B: 1 or more and less than 3 C: 3 or more and less than 5 D: 5 or more

(5) Evaluation of green color tone Mf8350Cdn (manufactured by Canon Inc.) was used as an evaluation machine. Using the yellow toners of Examples 1 to 23 and Comparative Examples 1 to 5, the electrostatic latent image on the photosensitive drum was developed and transferred onto a transfer material to obtain an image.

At this time, the fixing conditions were as follows. As a transfer material, Business 4200 (weighing 105 g / m ² , manufactured by Xerox) was used, a solid image with a toner loading of 0.50 mg / cm ^{2 was formed,} and the gloss was measured at an incident angle of 75 degrees The fixing temperature was adjusted so that the degree became 25-35.

  The density condition of each color is adjusted so that the gray scale can be reproduced as faithfully as possible in a full-color copy image using a gray scale and color patch manufactured by Kodak Co. as the original, and the maximum density of a yellow (Y) single-color copy is 1. The concentration was adjusted to be 1 or more.

  Then, a green image obtained by superimposing each of the yellow toner prepared with Mf8350Cdn in the above state and the cyan toner (toner (X)) prepared in Example 24 is output under a fixing condition of a glossiness of 20 to 25. The overlapping part at the highest density of each color was evaluated by the color difference (Δ 調: chromaticity difference) with the Kodak color patch.

For evaluation, the CMC (1: 1) chromaticity difference formula was introduced for the lightness L ^* , saturation C ^* , and hue angle h ^* of the image, and when the value of Comparative Example 1 was 100, the evaluation was as follows. .
A: ΔΕ ≦ 80
B: 80 <ΔΕ ≦ 90
C: 90 <ΔΕ ≦ 100
D: ΔΕ> 100

The CMC chromaticity difference formula is a chromaticity formula proposed in Journal of the Society of Dyers and Colorists, 100 128 (1984). , Lightness L ^* , saturation C ^* , hue angle h ^* , and evaluation is performed with correction of visual sensation, and is expressed by the following equation.
ΔE = [(ΔL ^* / lSL) ² + (ΔC ^* / CSC) ² + (Δh ^* / SH) ² ] ^1/2
(LSL: correction coefficient for lightness ΔL ^* , cSc: correction coefficient for saturation ΔC ^* ,
SH: Correction coefficient for hue angle Δh ^* )
The lightness L ^* , saturation C ^* , and hue angle h ^{* of the image} were measured using X-Rite SP68 (D65, viewing angle 2 degrees; manufactured by X-Rite).

(6) Evaluation of OHP transparency With respect to the transparency of the OHT image projected on the overhead projector (OHP), a solid image formed on the transparency film was projected using a commercially available overhead projector, and the projected image was visually observed. Observed and evaluated based on the following evaluation criteria.
A: Excellent transparency, no light / dark unevenness, and excellent color reproducibility.
B: Although there is slight unevenness in brightness, there is no practical problem.
C: Bright and dark unevenness and poor color reproducibility.
D: Practical problems due to poor transparency and color reproducibility.

(7) Evaluation of color difference between images on OHT and paper Also, for evaluation of color difference between images on OHT and paper, a solid image obtained using a remodeling machine of LBP7700C (manufactured by Canon Inc.) was used as an overhead projector. (OHP: 9550 manufactured by 3M) was used as a transmission image, and an image projected on a white wall surface was measured with a spectral radiance meter (PR650 manufactured by Photo Research).

The angle difference Δh ^* between the hue angle h ^* (OHT) of the image projected on the white wall surface and the hue angle h ^* (paper) on the paper was defined as shown below, and was shown in a four-step evaluation.
A: Δh ^* ≦ 5
B: 5 <Δh ^* ≦ 10
C: 10 <Δh ^* ≦ 20
D: Δh ^* > 20

[Examples 2 to 23 and Comparative Examples 1 to 5]
The same evaluation as in Example 1 was performed using toners (B) to (W) and (a) to (e) instead of the toner (A) of Example 1. The evaluation results are shown in Table 3.

DESCRIPTION OF SYMBOLS 101 Suction machine 102 Measuring container 103 Screen 104 Lid 105 Vacuum gauge 106 Air volume control valve 107 Suction port 108 Condenser 109 Electrometer

Claims (6)

A yellow toner having toner particles containing a yellow pigment, a binder resin, a release agent, and zinc phthalocyanine or a zinc phthalocyanine derivative,
The toner particles are particles obtained in an aqueous medium,
The interfacial tension A (mN / m) between the dispersion obtained by dispersing the yellow pigment in toluene and water is 20 mN / m or more and 35 mN / m or less,
A yellow toner characterized by satisfying a relationship of A <B, where B (mN / m) is an interfacial tension between a dispersion obtained by dispersing the zinc phthalocyanine or the zinc phthalocyanine derivative in toluene and water. 2. The yellow toner according to claim 1, wherein a hue angle (h ^* ) according to an L ^* a ^* b ^* color system of the toner is 95 ° or more and 110 ° or less.   3. The yellow toner according to claim 1, wherein the zinc phthalocyanine or the zinc phthalocyanine derivative is contained in an amount of 0.1% by mass to 10% by mass with respect to the yellow pigment.   The yellow toner according to claim 1, wherein the yellow pigment has a charge amount of −35 mC / kg or more and −12 mC / kg or less.   The toner according to any one of claims 1 to 4, wherein the release agent contains an ester wax, and a maximum endothermic peak in differential scanning calorimetry (DSC) measurement of the toner is 70 ° C or higher.   The yellow pigment is C.I. I. The yellow toner according to claim 1, wherein the yellow toner is CI Pigment Yellow 155.

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