JP2005242129A - Toner and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide toner having excellent low temperature fixing property and storage stability with which a sharp image having uniform gloss and high transparency of the image can be obtained, to provide toner having uniform distribution of charges, excellent environmental stability of charges, and stable charges even in copying processes for a large number of sheets, and to provide a method for manufacturing the toner. <P>SOLUTION: The toner is obtained in steps of dispersing a toner structural material containing at least two kinds of resin fine particles having different composition ratios and having 50 to 60°C Tg in an aqueous medium and aggregating and fusing the material. The resin fine particles (A) having the lowest average molecular weight Mw shows 1.0 to 2.0 coefficient of molecular weight distribution Mw/Mn and 3,000 to 30,0000 peak molecular weight Mp by GPC. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a toner for developing an electrostatic charge image in an image forming method such as electrophotography or electrostatic printing, or a toner for forming a toner image in a toner jet type image forming method, and a method for producing the same. In particular, the present invention relates to a toner used in a fixing method in which a toner image formed of toner is fixed on a print sheet such as a transfer material by heating and pressing, and a method for manufacturing the toner.

  Image forming method in which an electro-sensitive or magnetically sensitive fine particle such as toner is attracted to a latent image to make it visible in order to visualize an electric or magnetic latent image on a recording medium There is. A typical example thereof is an electrophotographic method. For example, as described in Patent Document 1, many methods are known. In this electrophotographic method, a photoconductive substance is generally used to form an electrical latent image on a photoreceptor by various means, and then the latent image is developed with toner to form a toner image. The toner image is transferred to a transfer material such as paper if necessary, and then a copy is obtained by fixing the toner image to the transfer material using heating, pressurization, or solvent vapor. .

  In recent years, the above-described technique has been used for output means such as a computer, so-called printer, because of its high print quality and quietness. Among them, the performance required for toner is increasing more and more. In order to improve the print quality, a technique for finely and faithfully reproducing the above-described latent image by reducing the particle diameter of the toner and further sharpening the particle size distribution has been actively studied. Further, it has been actively studied to control not only the color material in the toner but also the melting characteristics of the toner by the molecular weight distribution of the toner binder, such as the vividness of the color of the color image and the uniformity of the gloss.

  On the other hand, as printers are becoming cheaper and smaller, they are increasingly used in offices and homes, and it is also required to reduce the total power consumption, especially in the fixing process. Making the toner smaller, that is, developing a toner that can be fixed at a lower temperature, is a top priority. In addition, as the stability of quality, the storage stability of the toner, the charging stability during use, the charging stability in each environment, etc. are also required, and meeting these requirements at a high level is the conventional grinding system. It is difficult to obtain with toner. In order to solve this problem, a toner by a suspension polymerization method has been proposed. These are described in Patent Documents 2 to 6, for example. This method polymerizes substances to be encapsulated in the toner, such as binders, dyes, pigments and other colorants such as magnetic materials, carbon black, charge control agents, release agents such as wax and silicone oil, as necessary. Dissolve or disperse in a polymerizable monomer together with an initiator and a dispersant to form a polymerizable composition, and disperse it in an aqueous continuous phase containing a dispersion stabilizer using a dispersing device to form a fine particle dispersion. The dispersion is polymerized and solidified to obtain toner particles having a desired particle size and composition. By this method, it is possible to control the molecular weight of the binder and the structure of the capsule structure and the like, and it is possible to separate the functions of low-temperature fixability and quality stability, which could not be achieved with a pulverized toner having a uniform composition.

  In recent years, a toner using an emulsion aggregation method has been put on the market as a method of further developing the structure control. This is a method in which fine particles produced by emulsion polymerization are aggregated in water together with a colorant, a release agent and the like to produce toner particles having a relatively uniform particle size distribution. These are described in Patent Documents 7 to 9, for example. When a toner is prepared by this method, emulsified particles having an appropriate molecular weight distribution as a toner binder, a colorant finely dispersed in water, and a release agent are required in advance. By using these precise manufacturing techniques, it is possible to control the structure with a higher degree of freedom, and it is expected that the performance will be higher than that of the suspension polymerization toner.

  Actually, a technique is adopted in which two or more kinds of resin fine particles having different average molecular weights obtained by the emulsion polymerization method are aggregated to achieve both low temperature fixing property and high temperature offset property. These are described in, for example, Patent Documents 10 and 11, and a device is seen in the molecular weight distribution of the resin particles. In general, emulsion polymer particles tend to have a large molecular weight. In order to prevent this, it is essential to use a large amount of chain transfer agent. As a result, the distribution of the low molecular weight region of the binder is controlled to enable low-temperature fixing, but the current performance has not yet exceeded that of the suspension polymerization toner.

US Patent No. 2,297,691 Japanese Patent Publication No. 36-10231 Japanese Patent Publication No. 51-14895 JP-A-53-177735 JP-A-53-17736 JP-A-53-17737 Japanese Patent No. 2537503 Japanese Patent No. 2547016 Japanese Patent No. 2829880 Japanese Patent No. 3141785 Japanese Patent No. 3196754

  An object of the present invention is to provide a toner and a method for producing the same that solve the above-described problems.

  That is, an object of the present invention is to provide a toner that is low-temperature fixing, excellent in storage stability, uniform in image gloss, high in transparency, and capable of obtaining a vivid image.

  Another object of the present invention is to provide a toner having a uniform charge amount distribution and a high-definition image.

  Another object of the present invention is to provide a toner having excellent environmental stability of charge amount.

It is another object of the present invention to provide a toner having a stable charge amount even in a large number of copying operations.
Another object of the present invention is to provide a toner production method capable of achieving the object of the present invention.

The above object can be achieved by the present invention described below.
(1) A toner obtained by dispersing a toner constituent material containing at least two or more kinds of resin fine particles having a Tg of 50 to 60 ° C. and having a different composition ratio in an aqueous medium, and undergoing an agglomeration and fusing step. The toner, wherein the resin fine particle A having the lowest molecular weight Mw has a molecular weight distribution coefficient Mw / Mn of 1.0 to 2.0 and a peak molecular weight Mp by GPC of 3000 to 30000.
(2) The resin fine particles A are polymerized by adding a monomer composition containing at least a polymerizable monomer to a reaction medium containing at least an organic solvent and a polymer dispersion stabilizer having at least an acid-dissociable group. A fine resin particle formed by polymerizing the monomer composition in the presence of a polymerization initiator and depositing a polymer produced by polymerization from the polymerizable composition. The toner according to (1).
(3) The toner according to (2), wherein the polymerizable composition contains at least zinc phthalocyanine and an n-electron donating compound.
(4) The toner according to (3), wherein the n-electron donating compound has at least a radical generating group.
(5) A toner constituent material containing at least two kinds of resin fine particles having a Tg of 50 to 60 ° C. and different composition ratios and colorant fine particles is dispersed in an aqueous medium and obtained through an aggregation and fusion step. A method for producing a toner, wherein a resin fine particle A having the lowest average molecular weight Mw is a monomer composition containing at least a polymerizable monomer, and a polymer dispersion stabilizer having at least an organic solvent and an acid dissociation group. It is added to at least the reaction medium containing to form a polymerizable composition, the monomer composition is polymerized in the presence of a polymerization initiator, and a polymer produced by polymerization is precipitated from the polymerizable composition. A method for producing toner, characterized in that the fine particles are resin fine particles.

  According to the present invention, it is possible to provide a toner capable of obtaining a vivid image with excellent low-temperature fixing, excellent storage stability, uniform image gloss, high transparency, and a method for producing the same.

  Further, it is possible to provide a toner having a uniform charge distribution, excellent environmental stability of the charge amount, and a stable charge amount even in a large number of copying operations, and a method for manufacturing the same.

  The present invention will be described in detail below.

  In the present invention, a toner constituent material containing at least resin fine particles is dispersed in an aqueous medium, and toner particles are generated in an aggregation and fusion process. A known method can be used for the cohesion and fusion step. For example, a toner constituent material is dispersed in the presence of a surfactant, and an inorganic salt or an inorganic metal salt is added dropwise thereto to reduce the ability of the surfactant to cause aggregation until the toner particle size is reached. Thereafter, the aggregated particles are lightly fused at a temperature slightly higher than the Tg of the resin fine particles (aggregation step). Further, after stabilizing the particles by adding a large amount of a surfactant, sufficient heat is applied to completely fuse the resin particles (ripening step) to obtain toner particles.

  The feature of the present invention is to sharpen the molecular weight distribution on the low molecular weight side of the fine particles used as the binder component, whereby the above object can be achieved.

  The resin fine particles A used in the present invention must contain at least those having a molecular weight distribution coefficient Mw / Mn of 1.0 to 2.0. More preferably, it is 1.0-1.6. In general, in order to obtain storage stability of the toner, it is necessary to set the Tg of the binder to a certain temperature or more. For example, when Mw / Mn of the low molecular weight component is larger than 2.0, the average molecular weight of the binder is lowered for low temperature fixing. In addition, the Tg becomes too low due to the influence of the low molecular weight component, and it becomes difficult to obtain storage stability. Further, the resin fine particles A are required to have a peak molecular weight Mp of 3000 to 30000 by GPC. If Mp is less than 3000, Tg is substantially too low, and storage stability cannot be obtained.

  On the other hand, if it is larger than 30000, the melt viscosity of the toner becomes too high, and the low-temperature fixability cannot be obtained. Although details are unknown, it has been found that the charging stability of the toner in each environment is improved within these molecular weight ranges. Furthermore, the Tg of the resin fine particles used in the present invention needs to be 50 to 60 ° C. Similar to the molecular weight distribution, this is a physical property limited by low temperature fixability and storage stability. The effective particle size is from 50 nm to 2 μm, and preferably from 80 nm to 1 μm. A particle size of 50 nm or less is virtually impossible. On the other hand, when the particle size is larger than 2 μm, not only the toner particle size control becomes difficult, but also the particle size distribution tends to be broad, which is not preferable.

  The resin fine particles may be resin single particles or colored fine particles containing a colorant. When resin single particles are used, separate colorant fine particles are required as a toner constituent material. Known pigment dispersed particles can be used as the colorant fine particles. Examples thereof include carbon black, phthalocyanine pigments, quinacridone pigments, naphthol pigments, and azo pigments.

  In addition, as a method for producing resin particles, a known method can be used as long as the molecular weight and Tg can be achieved. A monomer composition containing at least a polymerizable monomer is used and at least an organic solvent and an acid dissociable group are contained. The polymer dispersion stabilizer is added to a reaction medium containing at least a polymerizable composition to form a polymerizable composition, and the monomer composition is polymerized in the presence of a polymerization initiator, and then polymerized from the polymerizable composition. A method obtained by precipitating the produced polymer is more preferable and the present invention can be achieved. When the emulsion polymerization method is used, it is not preferable because a large amount of chain transfer agent needs to be used. The same reason arises in the suspension polymerization method, but it is not preferable because it is difficult to further reduce the particle size.

  As the resin fine particles constituting the toner of the present invention, it is necessary to use particles having a composition or composition ratio different from that of the resin fine particles A. As particles other than the resin fine particles A, resin fine particles having an average molecular weight Mw higher than that of the particles A and a Tg of 50 to 60 ° C. are suitable for giving high-temperature offset resistance. As a method for producing these resin particles, a known method can be used, but the same method as the resin fine particles A or an emulsion polymerization method is preferably used.

  All the toner constituting materials that can be used in the present invention must be finely dispersed in an aqueous medium in the presence of a surfactant. An aqueous medium is water or alcohols, and may mix and use 2 or more types. As the surfactant, an anionic surfactant, a cationic surfactant, and a nonionic surfactant can be used. Specifically, sulfonate, fatty acid salt, sulfate ester salt, phosphate ester salt, amine Salts, quaternary ammonium salts, polyethylene glycols, alkylphenol ethylene oxides, and polyhydric alcohols. In the case of resin fine particles, it is only necessary to disperse in an aqueous medium containing a surfactant by gentle stirring. It is necessary to atomize the particle size to about 50 to 2 μm by applying shear. Examples of the disperser include a homogenizer, an attritor, a paint shaker, a sand mill, a dissolver, a high speed mill, a ball mill, and a dyno mill.

  The present invention is more preferably achieved when the resin fine particles are colored fine particles containing a colorant. In order to produce colored fine particles, for example, the following method is possible. For example, a polymer stabilizer and other additives are dissolved in the polymerizable monomer as required, and the pigment powder is gradually added while stirring to fully adjust to the solvent. Furthermore, the pigment is finely dispersed by applying mechanical shearing force with a disperser to obtain a monomer composition. Next, the composition is mixed with a reaction medium comprising an organic solvent, a polymer dispersion stabilizer, etc., a polymerization initiator is added, and the polymer is precipitated by light or heat while gently stirring to obtain colored polymerized toner particles. Is the method. At that time, by adding zinc phthalocyanine and an n-electron donating compound to the monomer composition before the dispersion treatment, the pigments have been made finer and the dispersibility of the pigment inside the particles has also been dramatically improved. To improve. Furthermore, since the n-electron donating compound contains a radical generating group, the dispersibility of the pigment is further improved, and the object of the present invention is achieved.

  In the present invention, pigments that can be used together with zinc phthalocyanine and an n-electron donating compound are limited to dark pigments among the above colorants because of the colorability of zinc phthalocyanine. Specifically, it is particularly preferably used for pigments such as phthalocyanine pigments and carbon black. The added amount of the pigment is preferably 5 to 20 parts by mass per 100 parts by mass of the polymerizable monomer.

  The polymerizable monomer that can be used for the production of the resin fine particles of the present invention is an addition polymerization or condensation polymerization monomer. Preferably, it is an addition polymerization monomer. Specifically, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene, 2 , 4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, p- Styrene such as n-dodecylstyrene and derivatives thereof; Ethylene unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; Unsaturated polyenes such as butadiene and isoprene; Vinyl chloride, vinylidene chloride, vinyl bromide and vinyl iodide Vinyl halides such as vinyl acetate, vinyl propionate, benzoic acid Vinyl esters such as Nyl; methyl methacrylate, ethyl methacrylate, propyl methacrylate, -n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate Α-methylene fatty acid monocarboxylic acid esters such as diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate, acrylic acid-n-butyl, acrylic acid isobutyl, propyl acrylate, acrylic acid-n-octyl, dodecyl acrylate Acrylates such as 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; vinyl methyl ether, vinyl ethyl ether, vinyl isobutyrate Vinyl ethers such as ruether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone; N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole and N-vinyl pyrrolidone; vinyl Naphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, acrylamide and the like.

  The organic solvent that can be used in the toner of the present invention is determined mainly from the solubility of the monomer and polymer. Specifically, for example, water, methyl alcohol, ethyl alcohol, modified ethyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, sec-butyl alcohol, tert-amyl alcohol, 3-pentanol, octyl Alcohols such as alcohol, benzyl alcohol, cyclohexanol, ether alcohols such as methyl cellosolve, cellosolve, isopropyl cellosolve, butyl cellosolve, diethylene glycol monobutyl ether, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, propion Esters such as ethyl acid, cellosolve acetate, hexane, octane, petroleum ether, cyclohexane, benzene, Hydrocarbons such as ruene and xylene, halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene and tetrabromoethane, ethers such as ethyl ether, dimethyl glycol and trioxane tetrahydrofuran, acetals such as methylal and diethyl acetal, formic acid, It is selected from acids such as acetic acid and propionic acid, sulfur such as nitropropene, nitrobenzene, dimethylamine, monoethanolamine, pyridine, dimethyl sulfoxide, dimethylformamide, and nitrogen-containing organic compounds. Also, two or more of these solvents can be mixed and used. The polymerizable monomer concentration with respect to the solvent is 1% by mass to 80% by mass, preferably 10% by mass to 65% by mass with respect to the solvent.

  The polymer dispersion stabilizer that can be used in the present invention needs to be a polymer containing at least one type of repeating unit having at least an acidic group, that is, a structure such as a carboxyl group or a sulfonic acid group. Thereby, the aggregation controllability in the aggregation process is improved, and the particle size distribution of the toner can be sharpened. As a result, the toner charge amount distribution becomes uniform, and high image quality can be achieved. In addition, the charge amount can be stabilized in each environment. Further, when the polymerization reaction is carried out together with the pigment, the pigment uptake property is improved, the coloring power of the toner is improved, and the pigment uptake efficiency is drastically improved. Specific examples include styrene sulfonic acid and (meth) acrylic acid. Any repeating unit that can be copolymerized with the acidic group can be used as long as it has a composition that dissolves in the organic solvent. Specific examples include styrene derivatives such as styrene, α-methylstyrene and p-hydroxystyrene, (meth) acrylic acid esters, vinyl alcohol, vinyl alkyl ethers, vinyl acetals, vinyl carboxylates, acrylamide, (meth ) Examples include acrylamide, acrylonitrile, vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, ethyleneimine, 2-alkyl-2-oxazolines, vinylformamide, ethylene, propylene, vinyl chloride, dimethylsiloxane, oxyalkylenes, and cellulose derivatives. it can. Two or more kinds of polymer dispersion stabilizers having different compositions may be used at the same time.

  The number average molecular weight of the polymer dispersion stabilizer is preferably in the range of 5,000 to 50,000. When the number average molecular weight exceeds 50,000, the viscosity of the reaction medium becomes too high and the particle size distribution tends to vary. Further, even when the number average molecular weight is less than 5,000, the dispersion stabilizing effect of the precipitated particles cannot be obtained, so that a good particle size distribution cannot be obtained. The concentration of the polymer dispersion stabilizer is preferably 0.1 to 50% by mass with respect to the organic solvent. More preferably, it is 0.1-30 mass%.

  Examples of the polymerization initiator used in the production of the resin fine particles of the present invention include known polymerization initiators. Specifically, 2,2-azobisisobutyronitrile, 2,2-azobis (2,4-dimethylvaleronitrile), 2,2-azobis (2-methylbutyronitrile), 1,1-azobis (Cyclohexane-1-carbonitrile), dimethyl-2,2-azobisisobutyrate, 4,4-azobis-4-cyanovaleric acid, 2,2-azobis (4-methoxy-2,4-dimethylvaleronitrile) Azo compounds such as benzoyl peroxide, peroxides such as methyl ethyl ketone peroxide, nucleophiles such as alkali metals, metal hydroxides, Grignard reagents, proton acids, metal halides, stable carbonium ions, etc. . The concentration of the polymerization initiator is preferably from 0.1 to 20 mass%, more preferably from 0.1 to 10 mass%, based on the polymerizable monomer.

  The polymerizable composition of the present invention needs to have zinc phthalocyanine and a compound capable of coordinating with it. In particular, the dispersibility of the black and blue pigments in the monomer composition is improved, and the efficiency of incorporating the pigment into the resin fine particles A and the coloring power can be improved. Considering the adsorptivity to the pigment, it is preferable to have a phthalocyanine skeleton. Here, the coordination property of the n-electron donating compound to the phthalocyanine center metal is particularly important, and it has an adsorption surface with the pigment. In view of the fact that a coordination bond is possible, zinc phthalocyanine having a five-coordinate structure is the most preferable embodiment.

  The n-electron donating compound capable of coordinating with zinc phthalocyanine is not particularly limited as long as it is mixed or dissolved in the polymerizable composition. It preferably has at least one skeleton selected from 1 to tertiary amine, imine, primary to tertiary amide, imide, thiol, thioester, thionyl, sulfide, and sulfoxide. The unshared electron pair in the nitrogen atom or sulfur atom in these skeletons exhibits excellent coordination ability and is easy to design as a ligand.

  Furthermore, the above-mentioned n-electron donor compound can be made into an oligomer or a polymer in order to show affinity for the dispersion medium, become steric hindrance to the pigment, and impart dispersibility to the pigment. For example, styrene-based polystyrene; acrylic-based polyacrylic acid, polymethacrylic acid, polyacrylate, polymethacrylate, etc .; ester-based polyesters; ether-based polyvinyl ether, polyvinyl methyl ether, etc .; vinyl-based polyvinyl alcohol, polyvinyl Examples thereof include oligomers or polymers such as butyral, and other polyurethanes and polypeptides may be used, and those in which a molecule having n-electron donating properties described above is incorporated into each copolymer may be mentioned.

  As the pigment contained in the polymerizable composition of the present invention, those subjected to surface treatment with the above-described pigment dispersant of the present invention are preferably used. By treating the pigment dispersion composition of the present invention with various pigment dispersers, a pigment dispersion paste containing a pigment surface-treated with the pigment dispersant of the present invention can be obtained. The optimum amount of the pigment dispersant at this time is determined by the desired dispersed particle diameter of the pigment, but in order to sufficiently adsorb the zinc phthalocyanine, which is the pigment adsorbing part, on the pigment surface, 0.3 part or more with respect to the pigment is required. is necessary. However, when the content is too high, the hue is affected by the coloration of zinc phthalocyanine. Considering these, it is preferable that the content of the metal compound constituting the pigment dispersant contained in the toner is 0.01% by weight to 2.5% by weight.

  Further, the n-electron donating compound for preventing steric hindrance by coordinating with zinc phthalocyanine and preventing reaggregation of pigments is preferably a polymer in the toner. In particular, the weight average molecular weight Mw is preferably 2000 to 100,000 in order to obtain a dispersion effect without impairing the toner fixing performance. Further, the optimum amount of the n-electron donating compound is better from the viewpoint of coordination efficiency to the metal compound, but it is not preferable that the amount is excessive in view of the influence on the toner physical properties. Considering these, the amount of the n-electron donating compound contained in the toner is preferably 0.01% by weight to 30% by weight.

  Furthermore, in the present invention, it is possible to incorporate the pigment into the resin fine particles A more preferably by using a compound having a radical generating group as the n-electron donating compound. Here, the radical generating group is a substituent that dissociates in the course of the polymerization reaction to generate a radical, anion, cation or the like. Specifically, an azo group, a peroxide group (peroxy group), a keto group ( α-diketo group) and persulfate group. As a result, the dispersibility of the pigment is improved, the transparency of the toner is improved, and the probability of the pigment existing on the particle surface is lowered, so that the particles are more likely to be fused with each other, and the time required for the cohesive fusion process is shortened. It becomes an aspect.

  As the toner constituting material of the present invention, release agent fine particles can be used. A well-known thing can be used as a mold release agent. Specific examples include polyethylene, polypropylene, carnauba wax, rice wax, montan wax, paraffin wax, and Fischer-Tropsch wax. The microparticulation is performed by putting a surfactant and wax in water, heating to about the melting point of the wax, and applying a high shearing force with a disperser such as a homogenizer. The particle size is preferably about 50 nm to 0.5 μm from the viewpoint of wax dispersibility.

  To the toner obtained by the present invention, additives as shown below can be externally added.

  As the fluidity-imparting agent, metal oxides (silicon oxide, aluminum oxide, titanium oxide, etc.) are preferably used. These are more preferably subjected to a hydrophobic treatment. As polishing agents, metal oxides (strontium titanate, cerium oxide, aluminum oxide, magnesium oxide, chromium oxide, etc.), nitrides (silicon nitride, etc.), carbides (silicon carbide, etc.), metal salts (calcium sulfate, barium sulfate, etc.) , Calcium carbonate, etc.) are preferably used. As the lubricant, fluorine resin powder (vinylidene fluoride, polytetrafluoroethylene, etc.) and fatty acid metal salts (zinc stearate, calcium stearate, etc.) are preferably used. As the charge controllable particles, metal oxides (tin oxide, titanium oxide, zinc oxide, silicon oxide, aluminum oxide, etc.), carbon black and the like are preferably used.

  The additive is used in an amount of 0.1 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of toner particles. These additives may be used alone or in combination.

  The toner obtained by the present invention can be used as a one-component developer or can be mixed with a carrier and used as a two-component developer.

A method for measuring the molecular weight distribution of the polymer composition (resin component) soluble in the fine resin particles and polymerization solvent used in the present invention will be described. It measured on the following measuring conditions using the GPC measuring apparatus (HLC-8120GPC Tosoh Corporation make).
Measurement conditions, column: TSKgel HM-M (6.0 mmφ × 15 cm), duplex: temperature: 40 ° C.
・ Flow rate: 0.6ml / min
・ Detector: RI
・ Sample concentration: 10 μl of 0.1% sample
Sample preparation is performed by placing the sample to be measured in THF and allowing it to stand for several hours, after which it is shaken sufficiently (until the sample is no longer united) and allowed to stand for another 12 hours. And let what passed the sample processing filter (pore size 0.45 micrometer) be a sample for GPC measurement. The calibration curve uses a molecular weight calibration curve created with a monodisperse polystyrene standard sample.

  Specific examples of toner particle size measurement used in the present invention will be shown.

  To measure the particle size of the toner particles, 0.1 to 5 ml of a surfactant (alkylbenzene sulfonate) is added to 100 to 150 ml of the electrolyte solution, and 2 to 20 mg of a measurement sample is added thereto. Disperse the electrolyte in which the sample is suspended with an ultrasonic disperser for 1 to 3 minutes, and measure the particle size distribution of 2 to 40 μm using the 100 μm aperture with the Coulter counter multisizer described above on the basis of volume, The number average particle size and the weight average particle size are calculated. In addition, for a toner having an average particle diameter of 1 μm or less, a scanning electron microscope (FE-SEM S-4500, manufactured by Hitachi, Ltd.) was used to take a 5,000 times photograph, and the horizontal direction was determined based on the photograph. The ferret diameter is measured so that the number of particles having a diameter of 0.05 μm or more is 300 or more. And the average was made into the number average particle diameter. The volume average diameter was calculated by spherical conversion.

  The Tg of the resin particles and toner particles of the present invention is measured using a DSC measuring device (manufactured by M-DSC TA-Instruments). As a measurement sample, 6 mg is precisely weighed and used. A precisely weighed measurement sample was put in an aluminum pan, and an empty aluminum pan was used as a reference, and measurement was performed at a temperature increase rate of 4 ° C./min at room temperature and normal humidity in a measurement temperature range of 20 ° C. to 200 ° C. . At this time, the measurement is performed with a modulation amplitude of ± 0.6 ° C. and a frequency of 1 / min. Then, Tg is calculated from the obtained reversing heat flow curve. In the calculation, the midpoint of a straight line connecting the intersections of the tangent lines of the baseline and the endothermic curve is obtained, and this is defined as Tg.

  A method for measuring the triboelectric charge amount of the toner obtained by the present invention will be described.

  When the toner and the carrier are converted into a developer, they are mixed so that an appropriate mixing amount (toner is 2 to 15% by mass) and mixed for 180 seconds with a turbula mixer. At this time, in the case of toner for one-component developer, TEFV (manufactured by Powdertech) is used as a standard carrier. This mixed powder (developer) is put in a metal container having a 635 mesh conductive screen at the bottom, sucked with a suction machine, and the difference in mass before and after suction and the potential accumulated in a capacitor connected to the container. From this, the triboelectric charge amount is obtained. At this time, the suction pressure is 250 mmHg. By this method, the triboelectric charge amount is calculated using the following formula.

Q (μC / g) = (C × V) / (W ₁ −W ₂ )
(W ₁ is the mass before suction, W ₂ is the mass after suction, C is the capacitance of the capacitor, and V is the potential accumulated in the capacitor.)

  The present invention will be described below with reference to examples, but the present invention is not limited to the examples. In addition, all the parts used in an Example show a mass part.

The production example of resin fine particles is shown below. The physical properties of the obtained particles are shown in Table 1.
(Resin fine particles 1)
Methanol 260 parts by weight Styrene-α-methylstyrene-acrylic acid-ethyl acrylate copolymer (copolymerization composition ratio = 1: 1: 1: 2, Mw (weight average molecular weight) = 46,000) 40 parts by weight・ A mixture of 98 parts by weight of styrene, 2 parts by weight of acrylic acid, and 2 parts by weight of 2,2′-azobisisobutyronitrile was put into a reaction vessel, and the solution was stirred for 60 minutes while bubbling nitrogen at 400 ml / min. Mix well. When the amount of dissolved oxygen at the start of the polymerization was measured when it became slightly cloudy, it was 0.3 mg / liter. The internal temperature at this time was 22 ° C. Subsequently, the temperature was raised gradually at a rate of 3 ° C./min, raised to 64 ° C., and refluxed in a nitrogen atmosphere for 12 hours.

After cooling to room temperature, solid-liquid separation and washing were repeated by decantation of the dispersion. For the washing, a solvent prepared at a ratio of 80% by weight of methanol to 20% by weight of water was used. This operation was repeated four times, and finally, washing was performed with water, and the resulting slurry was adjusted so that the solid content was 30 wt%. Resin fine particles 1 having a number average particle diameter (Dn) of 0.82 μm were obtained.
(Resin fine particles 2)
-Methanol 260 parts by weight-Styrene 84 parts by weight-N-butyl acrylate 14 parts by weight-Carbon black (made by Degussa) 6 parts by weight-Zinc phthalocyanine (reagent grade) 0.06 parts by weight-Styrene-4-vinylpyridine-hydroxyethyl Methacrylate copolymer (20/2/78, Mw21000) A mixture consisting of 0.8 parts by weight was charged into a glass bottle having glass beads and shaken for 6 hours by a paint shaker.・ Acrylic acid 2 parts by weight ・ Styrene-α-methylstyrene-acrylic acid-ethyl acrylate copolymer (copolymerization composition ratio = 1: 1: 1: 2, Mw (weight average molecular weight) = 46,000) After 40 parts by weight and 2 parts by weight of 2,2′-azobisisobutyronitrile were added and dissolved, the glass beads were removed with a nylon mesh and transferred to a reaction vessel. The solution was mixed well for 60 minutes while bubbling nitrogen at 400 ml / min. When the amount of dissolved oxygen at the start of polymerization was measured when it became slightly cloudy, it was 0.4 mg / liter. The internal temperature at this time was 25 ° C. Next, the temperature was raised gradually to a rate of 3 ° C./min, the temperature was raised to 64 ° C., and the mixture was refluxed in a nitrogen atmosphere for 12 hours.

After cooling to room temperature, solid-liquid separation and washing were repeated by decantation of the dispersion. For the washing, a solvent prepared at a ratio of 80% by weight of methanol to 20% by weight of water was used. This operation was repeated four times, and finally, washing was performed with water, and the resulting slurry was adjusted so that the solid content was 30 wt%. Black resin fine particles 2 having a number average particle diameter (Dn) of 0.90 μm were obtained.
(Resin fine particles 3)
Methanol 250 parts by weight Polyvinylpyrrolidone (BASF K-30) 50 parts by weight Styrene 84 parts by weight Nbutyl acrylate 14 parts by weight Acrylic acid 2 parts by weight 2,2'-azobisisobutyronitrile 2 A mixture consisting of parts by weight was put into a reaction vessel, and resin fine particles 3 having a number average particle diameter (Dn) of 0.78 μm were obtained by the same operation as resin fine particles 1.
(Resin fine particles 4)
A mixture comprising 74 parts by weight of styrene, 24 parts by weight of n-butyl acrylate, 2 parts by weight of acrylic acid, 2 parts by weight of dodecanethiol and 1 part by weight of carbon tetrabromide,
-Ion exchange water 150 weight part-Anionic surfactant (Neogen SC: Daiichi Kogyo Seiyaku Co., Ltd.) It mixes in a reaction container and emulsifies in 3 weight part liquid mixture. The solution was mixed well for 60 minutes while bubbling nitrogen at 400 ml / min. Next, 1 part by weight of ammonium persulfate was dissolved in some ion-exchanged water and dropped into the reaction vessel over 30 minutes. Thereafter, the internal temperature was set to 70 ° C. with an oil bath, and the polymerization reaction was carried out for about 8 hours.

  The obtained slurry was adjusted so that the solid content was 30 wt%. Resin fine particles 4 having a number average particle diameter (Dn) of 0.89 μm were obtained.

Thereafter, resin fine particles listed in Table 1 were produced by the same operation.
(Example of toner creation)
As shown in Table 1, resin fine particles A, B, and C were prepared. In Examples 1 to 4, resin fine particles A, B, and C were mixed so that the resin solid content was 40/50/10 parts by weight, and in Comparative Examples 1 and 2, resin fine particles A and B were 90/10. The mixture is mixed at a solid content ratio of parts by weight to prepare a mixed dispersion of resin fine particles.
(Example 1) 1 L Kolben is charged with the above resin fine particle mixed dispersion, and further anionic surfactant, Neogen SC (Daiichi Kogyo Seiyaku Co., Ltd.) 2 parts by weight Pigment Blue 15: 3 5 parts by weight Melting point 80 ° C 5 parts by weight of a wax emulsion (solid content 30 wt%: carnauba wax) was added and stirred. Further, 30 parts by weight of a 30 wt% NaCl solution was added dropwise over 30 minutes, and the internal temperature was heated to 56 ° C. and left for about 10 minutes. Furthermore, 3 parts by weight of Neogen SC was added, the internal temperature was raised to 95 ° C., and stirring was continued for about 60 minutes. After leaving to cool, decantation, filtration and washing were repeated to obtain a blue toner having a particle size of 5.8 μm. The evaluation results of the toner are shown in Table 2.
(Example 2) A 1-L Kolben was charged with a mixed dispersion of resin fine particles A, B, and C shown in Table 1, and anionic surfactant, Neogen SC (Daiichi Kogyo Seiyaku) 2 parts by weight Carbon black (Degussa) ) 5 parts by weight of a wax emulsion having a melting point of 80 ° C. (solid content: 30 wt%: carnauba wax) was added and stirred. Further, 30 parts by weight of a 30 wt% Nacl aqueous solution was added dropwise over 30 minutes, and the internal temperature was heated to 56 ° C. and left for about 10 minutes. Further, 3 parts by weight of Neogen SC was added, the internal temperature was raised to 95 ° C., and stirring was continued for about 60 minutes. After leaving to cool, decantation, filtration and washing were repeated to obtain a black toner having a particle size of 5.5 μm. The evaluation results of the toner are shown in Table 2.
(Example 3) A 1 L Kolben was charged with a mixed dispersion of colored resin fine particles of A, B, and C of Table 1, and further anionic surfactant, Neogen SC (Daiichi Kogyo Seiyaku Co., Ltd.) 2 parts by weight with a melting point of 80 ° C. 5 parts by weight of a wax emulsion (solid content 30 wt%: carnauba wax) was added and stirred. Further, 30 parts by weight of a 30 wt% Nacl aqueous solution was added dropwise over 30 minutes, and the internal temperature was heated to 56 ° C. and left for about 10 minutes. Further, 3 parts by weight of Neogen SC was added, the internal temperature was raised to 95 ° C., and stirring was continued for about 40 minutes. After allowing to cool, decantation, filtration, and washing were repeated to obtain a black toner having a particle size of 5.2 μm. The evaluation results of the toner are shown in Table 2.
(Example 4) A 1-L Kolben was charged with a mixed dispersion of resin fine particles of A, B, and C shown in Table 1, and anionic surfactant, Neogen SC (Daiichi Kogyo Seiyaku Co., Ltd.) 2 parts by weight Pigment Blue 15: 3 5 parts by weight of a wax emulsion having a melting point of 80 ° C. (solid content: 30 wt%: carnauba wax) was added and stirred. Further, 30 parts by weight of a 30 wt% Nacl aqueous solution was added dropwise over 30 minutes, and the internal temperature was heated to 56 ° C. and left for about 10 minutes. Furthermore, 3 parts by weight of Neogen SC was added, the internal temperature was raised to 95 ° C., and stirring was continued for about 60 minutes. After standing cooling, decantation, filtration and washing were repeated to obtain a blue toner having a particle size of 5.6 μm. The evaluation results of the toner are shown in Table 2.
(Comparative Example 1) 1 L Kolben was charged with a resin fine particle mixed dispersion of A and B in Table 1, and 2 parts by weight of anionic surfactant, Neogen SC (Daiichi Kogyo Seiyaku), Pigment Blue 15: 3 5 weights 5 parts by weight of a wax emulsion having a melting point of 80 ° C. (solid content: 30 wt%: carnauba wax) was added and stirred. Further, 30 parts by weight of a 30 wt% NaCl solution was added dropwise over 30 minutes, and the internal temperature was heated to 58 ° C. and left for about 10 minutes. Further, 3 parts by weight of Neogen SC was added, the internal temperature was raised to 95 ° C., and stirring was continued for about 120 minutes. After leaving to cool, decantation, filtration and washing were repeated to obtain a blue toner having a particle size of 5.4 μm. The evaluation results of the toner are shown in Table 2.
(Comparative Example 2) A 1-L Kolben was charged with a dispersion of resin fine particles A and B in Table 1 and 2 parts by weight of anionic surfactant, Neogen SC (Daiichi Kogyo Seiyaku) and carbon black (Degussa) 5 5 parts by weight of a wax emulsion having a melting point of 80 ° C. (solid content: 30 wt%: carnauba wax) was added and stirred. Further, 30 parts by weight of a 30 wt% NaCl solution was added dropwise over 30 minutes, and the internal temperature was heated to 57 ° C. and left for about 10 minutes. Further, 3 parts by weight of Neogen SC was added, the internal temperature was raised to 95 ° C., and stirring was continued for about 120 minutes. After leaving to cool, decantation, filtration and washing were repeated to obtain a black toner having a particle size of 5.5 μm. The evaluation results of the toner are shown in Table 2.

（保存安定性）
１０．０ｇのトナーを１００ｍｌガラス瓶に入れ、５０℃で１０日間放置した後に下記の基準で目視評価を行った。

(Storage stability)
10.0 g of toner was placed in a 100 ml glass bottle and allowed to stand at 50 ° C. for 10 days, and then visually evaluated according to the following criteria.

A ... No change B ... There is an aggregate, but it is loosened immediately C ... It is hard to loosen D ... No fluidity E ... Clear caking (environmental stability of charge amount)
Evaluation was performed according to the evaluation criteria shown in the following formula. The sample used was left in each environment for 24 hours.
A: (Charge amount of 35 ° C./75% RH) − (Charge amount of 17 ° C./10% RH) <15 (μC / g)
B: 15 ≦ (charge amount of 35 ° C./75% RH) − (charge amount of 17 ° C./10% RH) <25
C: 25 ≦ (charge amount of 35 ° C./75% RH) − (charge amount of 17 ° C./10% RH)
(Fixing start temperature)
Using a full-color copier (CLC500; manufactured by Canon Inc.), a transfer machine is developed and transferred at a development contrast of 320 V on a transparency sheet (CG3300: manufactured by 3M) in an environment of a temperature of 23 degrees / humidity of 65% RH. An unfixed solid image having a toner loading of 0.75 mg / cm ² was obtained. The fixing test is performed on the obtained roller with an external fixing device (no oil application function; roller diameter 40φ) whose surface of the fixing roller is a fluororesin at a process speed of 30 mm / sec while adjusting the roller surface temperature. It was. The obtained fixed image (including low-temperature offset image) was applied with a load of 50 g / cm ² and rubbed 10 times with sylbon paper [Lenz Cleaning Paper “dasper (R)” (Ozu Paper Co. Ltd)], The temperature at which the density reduction rate before and after rubbing is less than 10% is defined as the fixing start point.
(Transparency)
The fixed image on the OHP sheet (toner amount 0.7 mg / cm ² ) was converted into a transmission image by an overhead projector (OHP: 9550 manufactured by 3M), and L * and c * of the image projected on the white wall surface were spectral radiance. It was measured with a meter (PR650 manufactured by Photo Research) and evaluated as a colorimetric index p = (95−L *) / c * of the projected image.
A (good): 0.50 ≦ p <0.60
B (possible): 0.60 ≦ p <0.65
C (bad): 0.65 ≦ p
(Glossy)
For the measurement of glossiness, a VG-10 glossiness meter manufactured by Nippon Denshoku was used. In the measurement, first, it is set to 6V by a constant voltage device, and then the light projection angle and the light reception angle are respectively adjusted to 60 °, and the sample image is placed on the sample table after the standard setting using the zero point adjustment and the standard plate. Then, the measurement was performed with three sheets of white paper overlaid on top of each other, and the numerical value shown in the marking section was read in% units.
(Coloring power)
A solid image fixing test is performed in the same manner as the fixing start temperature evaluation. At that time, the applied amount of toner is 0.60 mg / cm ^2, and the image density is measured when fixing is performed at a fixing temperature at which the gloss value is 9. For the concentration measurement, Macbeth RD918 (manufactured by Macbeth) was used.
(Scattering)
An image formation test was performed using a checker pattern of 80 × 50 μm, and the sharpness of the toner image, the scattering of the toner on the non-image area, and the presence or absence of a black part defect were evaluated using a microscope according to the following criteria. For the output, the above-described full-color copying machine (CLC500; manufactured by Canon Inc.) was used, and the images after initial and after 1000 continuous copying were observed and evaluated.

A: Toner splattering on non-image area is almost free from black part B: Slight toner is present in non-image area and image edge is slightly blurred C: Large amount of toner in non-image area Scattered and unclear edge of image

  The present invention can be applied to a toner used in a fixing method in which a toner image is fixed by heating and pressing on a print sheet such as a transfer material and a manufacturing method thereof.

Claims (5)

A toner obtained by subjecting a toner constituent material containing at least two or more kinds of resin fine particles having a Tg of 50 to 60 ° C. and different composition ratios to an aqueous medium and undergoing an agglomeration and fusion step,
The toner, wherein the resin fine particle A having the lowest average molecular weight Mw has a molecular weight distribution coefficient Mw / Mn of 1.0 to 2.0 and a peak molecular weight Mp by GPC of 3000 to 30000.   A polymerizable composition in which the resin fine particle A is added to a reaction medium containing at least a polymer dispersion stabilizer having at least an organic solvent and an acid-dissociable group. A resin fine particle obtained by polymerizing the monomer composition in the presence of a polymerization initiator and precipitating a polymer produced by polymerization from the polymerizable composition. 1. The toner according to 1.   The toner according to claim 2, wherein the polymerizable composition contains at least zinc phthalocyanine and an n-electron donating compound.   The toner according to claim 3, wherein the n-electron donating compound has at least a radical generating group. Production of a toner obtained by dispersing a toner constituent material containing at least two kinds of resin fine particles having a Tg of 50 to 60 ° C. and different composition ratios and colorant fine particles in an aqueous medium and performing an agglomeration and fusion process. A method,
The resin fine particle A having the lowest average molecular weight Mw adds a monomer composition containing at least a polymerizable monomer to a reaction medium containing at least a polymer dispersion stabilizer having at least an organic solvent and an acid-dissociable group. And forming a polymerizable composition, polymerizing the monomer composition in the presence of a polymerization initiator, and depositing a polymer produced by polymerization from the polymerizable composition. A method for producing a toner.