JPH02269365A - Polymerized color toner and production thereof - Google Patents

Abstract

PURPOSE:To obtain a good spectral reflection characteristic, color mixability and transparency by processing an org. pigment a a coloring agent by specified isocyanate. CONSTITUTION:The org. pigment of the coloring agent is processed by the isocyanate expressed by formula I (in the formula I, R denotes 1 to 20C alkyl group, alkenyl group without contg. active hydrogen or 1 to 20C alkyl group, alkenyl group contg. at least one kind among N, S, O and halogen atom and without contg. active hydrogen). The maintenance of the dispersion stability of the dispersed pigment leads to the additional improvement in the pigment dispersibility. A highly bulky group is, thereupon, introduced into the pigment particle surface and the reflocculation of the dispersed pigment particles is prevented by utilizing the steric hindrance effect thereof, by which the dispersibility of the pigment is improved. The polymerized color toner having the excellent spectral reflection characteristic, color mixability and transparency is obtd. by improving the dispersibility of the coloring agent in such a manner.

Description

[Detailed description of the invention]

[Industrial Application Field 1] The present invention relates to a polymerized color toner used for visualizing an electrical latent image in electrophotography, electrostatic photography, etc., and a method for producing the same.

[Prior Art] Conventionally, toners have generally been produced by melt-mixing a coloring agent in a thermoplastic resin, uniformly dispersing the mixture, and then using a pulverizer/classifier to produce a toner having a desired particle size. Although this production and usage method can produce quite excellent toner,
For example, the selection of toner materials is limited because the resin colorant dispersion must be sufficiently brittle (and must be able to be pulverized in economically viable manufacturing equipment). In order to overcome the problems of toner produced by the pulverization method, a method for producing toner using a suspension polymerization method has been proposed in Japanese Patent Publication No. 36-10231, Japanese Patent Publication No. 43-10799, Japanese Patent Publication No. 51-14895, etc. In method 1, a monomer composition consisting of a polymerizable monomer, a colorant, a polymerization initiator, and optionally a crosslinking agent, a charge control agent, and other additives is mixed into a continuous phase containing a dispersion stabilizer, For example, toner particles having a desired particle size can be obtained by dispersing in an aqueous phase using an appropriate stirrer and simultaneously causing a polymerization reaction.This suspension polymerization method does not include a mechanical pulverization step. There are no inconveniences caused by pulverization as seen in pulverization methods,
Furthermore, the obtained toner is spherical in shape and has various advantages such as excellent fluidity and uniform triboelectric charging properties. However, even with polymerized toners having such excellent properties, there are problems that need to be solved. In other words, suspension polymerization toner is produced by granulating a polymerizable monomer system in water and causing a polymerization reaction, so it is difficult to use materials with poor dispersion stability or hydrophilic materials in the monomer system. Furthermore, materials that inhibit radical reactions cannot be used. For this reason, there are considerable restrictions on the selection of materials for colorants, which are essential components of color toners. For example, when dyes are used as colorants, there are no problems with dispersion stability as most of them are soluble in monomers, but most dyes have polymerization inhibiting properties, making it impossible to obtain a cured product. result. In addition, when pigments are used as colorants, there is no problem with polymerization inhibition, but there are problems with dispersion stability in the monomer system, and pigment aggregation tends to occur during granulation, resulting in poor granulation stability. The resulting toner often has a broad particle size distribution and lacks homogeneity. As described above, both dyes and pigments have advantages and disadvantages as colorants, but when material costs are considered, it is preferable to use pigments. Furthermore, in recent years, there has been a demand for reducing toner consumption in copying machines, and one of the means for achieving this is to improve the coloring power of toner. One way to improve this coloring power is to improve the dispersibility of the colorant, form aggregates, and disperse it uniformly.As mentioned above, in polymerized toners, colorants, especially pigments, Improving the dispersibility of pigments into monomer systems has become an important issue.As a means of improving dispersion in such polymerizable monomer systems and preventing aqueous phase migration, it is possible to improve the surface affinity of pigments. There is a method of treating pigments to make them oily. Methods of treating pigments to make them lipophilic have been studied for some time, and methods such as derivatization of pigments, coating with resins, treatment with coupling agents, etc. have been proposed. For example, pigments For the derivatization of
Aminoalkylation treatment of copper phthalocyanine pigment according to No. 1, JP-A-61-168666, U, S,
P. Examples include a method of introducing a substituent into a quinacridone pigment as disclosed in JP-A-57-28162, and a method of intermolecular coupling of a naphthol-based pigment as disclosed in JP-A-57-28162. These are preferred methods because the pigments are treated with chemical bonds, but the treatment methods differ depending on the pigment, and the properties of the treated pigments differ depending on the pigment. It is disadvantageous in terms of unifying prescriptions. Also, JP-A-58-76
Publication No. 48 discloses a toner using a pigment treated with a titanium coupling agent, but the pigment in this publication is essentially a magnetic material, carbon black, and is an organic pigment that does not have reactive active sites on the surface. There is no processing effect on this. On the other hand, resin coating is a surface treatment method that does not require any type of pigment. For example, JP-A-58-215461
Examples include pigment coating using an acrylic acid aminoalkylate polymer in Japanese Patent Publication No. 14273/1984, and pigment coating using a urea resin in Japanese Patent Publication No. 14273/1983.
When dispersed in a monomer system such as in a polymerization method, the monomer functions as a solvent, and the coating agent dissolves and detaches, not only making it impossible to obtain the desired dispersibility, but also causing the detached polymer to form. This may give undesirable results such as adversely affecting the particle quality and physical properties of the toner. As mentioned above, the lipophilic treatment of pigments suitable for polymerization methods is still not sufficient, and as a result, color toners, especially polymerized toners for full color, that are sufficient in terms of cost and performance have not been obtained. The current situation is that there is no such thing. [Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned current situation, and its main purpose is to provide a film that has good spectral reflection characteristics, color mixing properties, and transparency, and has excellent development properties. An object of the present invention is to provide a polymerized color toner having properties and a method for producing the same. Another object of the present invention is to provide a polymerized color toner that is stable during polymerization of a polymerizable monomer system, has stable charging characteristics, and has excellent developability, and a method for producing the same. [Means and Effects for Solving the Problems 1] The polymerized color toner of the present invention was developed to solve the above-mentioned problems. In the polymerized color toner obtained by suspension polymerization in the colorant, the colorant is an organic pigment,
-Formula %Formula % (1) (In the formula, R is an alkyl group or alkenyl group having 1 to 20 carbon atoms that does not contain active hydrogen, or contains at least one kind of N, S, O, or halogen atom, and R is an active hydrogen is an alkyl group or alkenyl group having 1 to 20 carbon atoms not containing . The present invention will be described in detail below. As a result of extensive studies, the present inventors have found that by treating an organic pigment with an isocyanate ester, a bulky group is introduced onto the surface of the organic pigment, and the dispersibility of the organic pigment is significantly improved due to the steric hindrance effect. I found out. That is, in the case of a polymerized toner, since a high shearing force is applied at the stage of preparing the monomer system in the manufacturing method, the dispersibility of the pigment is better than that in the case of mixed wires during the production of a pulverization method toner. However, in the former case, compared to the latter case, the pigment once dispersed remains in the polymerizable monomer system with low viscosity until the completion of polymerization, which causes a problem of re-agglomeration. That is, maintaining the dispersion stability of the dispersed pigment leads to further improvement of pigment dispersibility. Therefore, the dispersibility of the pigment can be significantly improved by introducing a bulky group onto the surface of the pigment particle and utilizing its steric hindrance effect to prevent the dispersed pigment particles from re-agglomerating. The isocyanate ester may be one having an incyanate group in a polymer chain or a side chain, and the reaction mechanism is, for example, as follows. Pigments Any of a wide variety of isocyanate esters can be used to treat pigments. This isocyanate ester can be used in storage, as a gas, or as a non-aqueous solution. Generally, an isocyanate ester and a pigment are brought into contact with each other to form a chemical bond with the hydroxyl group on the surface of the pigment through an addition reaction as shown in formula (2). When this treatment is carried out with a gaseous isocyanate compound, the dry pigment particles are treated in a saturated isocyanate compound atmosphere at a high temperature of 100 to 200° C. for about 1 hour. Alternatively, there is a method of milling for 1 to 4 hours in a non-aqueous solution of an isocyanate compound maintained at 15 to 30°C. Generally, the higher the temperature of the solution, the faster the reaction rate. However, if the reaction is made too fast, the pigment particles will agglomerate. In order to achieve a similar dispersion without agglomeration, it is important to maintain an appropriate temperature and reduce agglomerates by milling, and for this purpose, it is desirable to mill continuously until the processing is completed. Compounds containing incyanate groups include n-propyl isocyanate, butyl isocyanate, hexadecyl isocyanate, octadecyl isocyanate, phenyl isocyanate, tolyl isocyanate, 3,4-dichlorophenyl isocyanate, m-nitrophenyl isocyanate, It is selected from aromatic and aliphatic isocyanate compounds such as tosyl isocyanate. All commonly known pigments can be used as pigments to be treated, but those that do not have hydroxyl groups, or those that do have a small number of hydroxyl groups, can be oxidized using plasma or an oxidizing agent as described below. good. (1) Plasma oxidation treatment Plasma oxidation treatment can be performed using an apparatus that generally performs plasma treatment. Figure 1 shows an outline of a typical device. In the figure, 1 is a motor, 2 is a high frequency power source, 3 is a high frequency supply electrode, 4 is a magnetic stirring device, and 5 is a magnetic stirrer. The plasma oxidation process using this apparatus will be described below. The pigment is placed in a reaction container, and the pressure inside the reaction container is reduced to thoroughly dry the pigment. The amount of pigment processed, degree of pressure reduction, and drying time vary depending on the state of the pigment, but as a guide, the amount of processed 2
Appropriately, the drying time is 0g, the degree of vacuum is 0°2 Torr or less, and the drying time is about 1 hour. After drying the pigment, supply oxygen while maintaining a predetermined degree of vacuum,
The conditions for activating the magnetic stirring device 4 and applying high frequency to perform the oxidation treatment vary depending on the type of pigment, but the appropriate high frequency output is 20 to 100 W, and the output is 20 to 100 W.
If it is smaller than 0 W, the pigment will not be treated sufficiently, and if it is larger than 100 W, ashing due to combustion of the pigment surface will progress. The appropriate degree of vacuum is 0.5 to 5 Torr; if it is less than 0.5 Torr, the oxygen concentration in the container will be low and the processing time will be long (if it is greater than 5 Torr, high frequency It is inappropriate to increase the output of the
~60 minutes is appropriate. (2) Oxidation treatment using an oxidizing agent As the oxidizing agent used in the present invention, one that binds oxygen to the surface of an organic pigment through an oxidation reaction and forms a polar compound thereon can generally be used, but particularly preferably, For example, ozone, hydrogen peroxide, peroxides and their derivatives such as ammonium peroxide disulfate, nitric acid and its salts, perchloric acid and its salts, hypochlorous acid and its salts, permanganic acid and its salts, chromic acid. oxoacids and their salts. Note that, if necessary, measures can be taken to increase the activity of the oxidizing agent, such as using the oxidizing agent in combination with an acid or alkali, or an oxidation catalyst. Although it is not clear what type of structure on the surface causes the polarity imparted by such oxidation treatment, by allowing an oxidizing agent to act on the organic pigment, the surface of the organic pigment is oxidized and decomposed. It is thought that polar functional groups, such as hydroxyl groups, are formed on the surface, and that polarity is thereby expressed. Methods for causing an oxidizing agent to act on an organic pigment include a dry method in which the pigment is brought into contact with an oxidizing gas or vapor, and a method in which the oxidizing agent is added to an aqueous suspension obtained by suspending an organic pigment in water. There is a wet method in which an organic pigment is suspended in water containing water and an oxidizing agent is applied thereto, but the wet method is particularly convenient to use. In addition, when processing by a wet method, if necessary, an anionic, cationic, amphoteric or nonionic surfactant may be used to suspend the pigment. In order to maximize the effect of the oxidation treatment, it is desirable to oxidize the surface of the pigment uniformly.As a method for doing so, it is preferable to stir the aqueous suspension of the pigment when performing the oxidation treatment. Furthermore, it is more preferable to perform the treatment by applying shear to uniformly and finely grind the pigment while sufficiently expanding the surface to be oxidized. The shear force is applied to the grinding aids, e.g. glass, in aqueous suspension.
Generated by moving ceramic products, metal spheres, or sand with a high-speed rotating stirrer. Suitable devices include those commonly used for pigment dispersion, such as sand mills, ball mills, and attritors. In order to effectively generate shearing force and to sufficiently spread the pigment surface subject to oxidation, the pigment content in the aqueous suspension is approximately 1 to 10% of the total pigment surface.
The amount of the grinding auxiliary is preferably 40% by weight, more preferably 5-30% by weight, and the volume of the grinding auxiliary is generally 0.3-1.5 times the volume of the aqueous suspension. It will be done. The treated organic pigment is filtered, washed, dried, and pulverized in a conventional manner for use. The oxidizing agent concentration, oxidizing treatment time, and temperature when the oxidizing agent is applied must be determined depending on the type of oxidizing agent, but if the degree of oxidation becomes too large, the change in hue will become large, which is not advantageous. By controlling oxidation conditions, hue, weather resistance,
It is possible to oxidize organic pigments without substantially adversely affecting fastness and the like. The temperature at which the oxidizing agent is applied is preferably 60°C or lower. This is because if the temperature exceeds 60°C, the hue change becomes large and it becomes difficult to control the oxidation conditions. However, depending on the type of pigment or oxidizing agent, it may be better to process at a temperature exceeding 60°C. As described above, the pigment that has been oxidized by plasma or an oxidizing agent is treated with isocyanate ester and used as a coloring agent for color toners. The polymerized color toner used in the present invention can be obtained by the following method. That is, wax in the polymerizable monomer,
A monomer system containing other additives such as colorants and polymerization initiators and uniformly dissolved or dispersed using an ultrasonic dispersion machine, homogenizer, etc. is usually added to an aqueous phase (i.e., a continuous phase) containing a suspension stabilizer. Disperse using a stirrer, homomixer, homogenizer, etc. Preferably, the stirring speed and time are adjusted so that the monomer droplets have the desired toner particle size, generally 30 μm or less, and thereafter the stirring is performed so that this state is almost maintained by the action of the dispersion stabilizer. The polymerization temperature should be set to a temperature of 40°C or higher, numerically 50 to 90°C. 0 After the reaction, the generated toner particles are washed. , collected by filtration and dried. In the suspension polymerization method, 300 to 300 parts of water is usually added to 100 parts by weight of monomer.
Preferably, 3000 parts by weight are used as dispersion medium. Examples of polymerizable monomers that can be applied to the polymerized toner include styrene, 0-methylstyrene, ■-methylstyrene, p-methylstyrene, and
- Styrene and its derivatives such as methylene, rustyrene, p-methoxystyrene, p-ethylstyrene; methyl methacrylate, ethyl methacrylate, propyl methacrylate, lobutyl methacrylate, isobutyl methacrylate,
Methacrylic acid esters such as n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate, Acrylic acid esters such as n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; Vinyl monomers include acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide. These monomers can be used alone or in combination. Among the above-mentioned monomers, it is preferable to use styrene or a styrene derivative alone or in combination with other monomers as a polymerizable monomer in terms of the development characteristics and durability of the toner. In addition, it is more preferable to polymerize the monomer by adding a polymer or copolymer having a polar group as an additive during polymerization of the monomer. It is preferable to suspend and polymerize a polymerizable monomer system to which a copolymer or cyclized rubber is added in an aqueous phase in which the polar polymer and a dispersant with an opposite charge are dispersed. The cationic or anionic polymer, copolymer or cyclized rubber contained in the polymer system is polymerized with the oppositely charged anionic or cationic dispersant dispersed in the aqueous phase to form the toner particles. Electrostatic attraction on the surface,
By covering the particle surface with the dispersant, it prevents the particles from coalescing and stabilizes them. At the same time, the polar polymer added during polymerization collects on the surface layer of the particles that will become the toner, forming a kind of shell-like shape, The particles become pseudo-capsules. A relatively high molecular weight polar polymer, copolymer or cyclized rubber is used to give toner particles excellent blocking properties and development abrasion resistance, while a relatively low molecular weight internal material improves fixing properties. Polar polymers (including polar copolymers) that can be used in the present invention and oppositely charged Examples of the dispersant are shown below. (i) Examples of the cationic polymer include polymers of nitrogen-containing monomers such as dimethylaminoethyl methacrylate and diethylaminoethyl acrylate, or copolymers of styrene, unsaturated carboxylic acid esters, etc., and the nitrogen-containing monomers. . (ii) Examples of anionic polymers include nitrile monomers such as acrylonitrile, halogen-containing monomers such as vinyl chloride, unsaturated carboxylic acids such as acrylic acid, unsaturated dibasic acids, and unsaturated dibasic acids. There are anhydride and nitro monomer polymers. (iff) As an anionic dispersant, Aerosil 1
There are colloidal silicas such as 200, $300.8380 (manufactured by Nippon Aerosil Co., Ltd.). (iv) Aluminum oxide as a cationic dispersant;
Examples include hydrophilic positively charged silica fine powder such as aminoalkyl-modified colloidal silica. Cyclized rubber may be used instead of the polar polymer. Such a dispersant is preferably used in an amount of 0.2 to 20 parts by weight, more preferably 0.2 to 20 parts by weight, based on 100 parts by weight of the polymerizable monomer.
It is 3 to 15 parts by weight. On the other hand, as the charge control substance to be added as necessary, commonly known ones are used. For example, nigrosine, azine dyes containing an alkyl group having 2 to 16 carbon atoms, metal complex salts of monoazo dyes, salicylic acid, dialkyl Metal complex salts of salicylic acid and the like are used. As the polymerization initiator, any suitable polymerization initiator such as 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'- Azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,
Azo or diazo polymerization initiators such as 4-dimethylvaleronitrile and other azobisisobutyronitrile (AIBN); benzoyl peroxide, methyl ethyl ketone peroxide, isopropyl peroxy carbonate, cumene hydroperoxide, 2.4- Examples include peroxide-based polymerization initiators such as dichloryl benzoyl peroxide and lauroyl peroxide. Generally, about 0.5 to 10% of the polymerization initiator based on the weight of the polymerizable monomer is sufficient. Further, a fluidity modifier may be mixed (externally added) with toner particles and used. Examples of the fluidity modifier include colloidal silica, fatty acid metal salts, and fine Teflon powder. In addition, fillers such as calcium carbonate and finely powdered silica are added for the purpose of increasing the volume.
It may be blended into the toner in a range of 5 to 20% by weight. The polymerized toner obtained in the present invention can be applied to known dry electrostatic image development methods without particular limitations. For example, two-component development methods such as cascade method, magnetic brush method, microtoning method, and two-component AC bias development method; powder cloud method and fur brush method: toner is held on a toner carrier by electrostatic force. It is applicable to a non-magnetic component development method in which toner is transported to a developing section and subjected to development; an electric field curtain development method in which toner is transported to a developing section and developed by an electric field curtain method. [Examples] The present invention will be described in more detail below based on Examples. <Oxidation treatment of pigments> (1) Plasma oxidation treatment of copper phthalocyanine blue (C, 1, pigment blue 15:3) Add 20 g of copper phthalocyanine blue into the reaction vessel of the plasma oxidation treatment apparatus shown in Figure 1, The inside of the container is 0.
The pressure was reduced to 2 torr and the copper phthalocyanine blue was dried for about 2 hours. After drying, oxygen was supplied into the container at loOmR/win to adjust the degree of vacuum to 1.2 torr. After adjusting the rotation speed of the reaction vessel and magnetic stirring device so that the copper phthalocyanine blue is sufficiently stirred, high frequency (13,56M)
Iz, 30W) was oxidized for 40 minutes to obtain a treated pigment. (2) Plasma oxidation treatment of quinacridone magenta (C, 1, Pigment Red 122) A treated pigment was obtained by carrying out the same operation as in the case of copper phthalocyanine blue, except that the high frequency output was 100 W and the treatment time was 15 minutes. (3) Oxidation treatment of quinacridone magenta (C, 1, Pigment Red 122) using an oxidizing agent (sodium hypochlorite) Add 25 g of quinacridone magenta to 200 g of a sodium hypochlorite aqueous solution (available chlorine concentration 5%), The mixture was treated in a ball mill with 400 g of made balls (1.5 cm in diameter) at room temperature (about 20° C.) for 48 hours. After filtration and washing, the treated pigments were dried and ground to obtain treated pigments.Table 1 shows the physical properties of each treated pigment. (Margin below) Table 1: Physical properties of treated pigments Add 7 g of plasma-treated pigment steel phthalocyanine blue (C, 1, Pigment Blue 15:3) to a solution of 170 g of styrene and 30 g of 2-ethylhexyl acrylate and disperse thoroughly. I let it happen. Octadecyl isocyanate leg was added to this and reacted at 60°C for 4 hours. Furthermore, the above formulation was added and dissolved or dispersed while maintaining the mixture at 60°C to prepare a monomer system. Separately, 10g of aminoalkyl-modified colloidal silica was added to 1200p of ion-exchanged water, and the above monomer composition was added to a dispersion medium system whose pH was adjusted to 6 with hydrochloric acid.
T at 0°C, 8.00 Or, p using a homomixer.
, Il for 60 minutes to granulate the monomer composition. After that, the polymerization was completed in 20 hours by heating and stirring at 60°C with a paddle stirring blade. After the polymerization was completed, the reaction product was cooled, sodium hydroxide was added, the dispersant was dissolved, and the polymerization was carried out by filtration, washing with water, and drying. Got toner. The obtained toner had a volume average particle size of 10. sI&m (aperture diameter 100s+m
), and the tripo value measured by the blow-off method for iron powder (ZOO/300 mesh) was -20 uc/g. Further, visual inspection using a microscope confirmed that the pigment was sufficiently dispersed in each toner particle. A developer was prepared by mixing 0.5 g of hydrophobic silica treated with amino-modified silicone oil with 100 g of the toner obtained above. Use this developer on a Canon copier NP-3525.
When the image was printed using a reversing machine, the obtained image was of high quality and had no fog, and the image density was stable at 1.4 or higher. In addition, images with excellent transparency were obtained when printing on the trap pen. 11 As a pigment, plasma-treated quinacridone magenta (C,
Example 1 except that Pigment Red 122) was used.
A polymerized toner was obtained in the same manner as above. The obtained toner had a volume average particle size of 1008 μm (aperture diameter 1 oops) measured by Coulter Counter, and a tripo value of -19 gc/g measured by blow-off method against iron powder (200/300 mesh). Further, visual inspection using a microscope confirmed that the pigment was sufficiently dispersed in each toner particle. A developer was prepared by mixing 0.5 g of hydrophobic silica treated with amino-modified silicone oil with 100 g of the toner obtained above. When this developer was used to print an image using a Canon NP-3525 reversing machine, the resulting image was of high quality, free from fog, and had a stable image density of 1.4 or higher. In addition, images with excellent transparency were obtained when printing on the trap pen. Oxidizing agent-treated quinacridone magenta (C, 1,
Pigment Red 122), styrene and dimethylaminoethyl methacrylate copolymer (
Copolymerization ratio 9:1 moi)/moj! . A polymerized toner was obtained in the same manner as in Example 1 except that 10 g (vin = 20.000) was used. The obtained toner had a volume average particle size of 11. OIAm (Aperture diameter 10014m
), the tripo value measured by the blow-off method for iron powder (200/300 mesh) was +20 Pc/g. Also,
Visual observation using a microscope confirmed that the pigment was sufficiently dispersed in each toner particle. A developer was prepared by mixing 0.5 g of hydrophobic silica treated with amino-modified silicone oil with 100 g of the toner obtained above. When this developer was used to produce an image using a Canon copier NP-3525, the resulting image was of high quality, free from fog, and had a stable image density of 1.4 or higher. In addition, images with excellent transparency were obtained when images were printed on the trap pen. A polymerized toner was obtained in the same manner as in Example 1, except that untreated copper phthalocyanine blue (C,1, pigment blue 15:3) was used as the L-diaphragm pigment. The obtained toner had a volume average particle diameter of 10.9% m (aperture diameter 100 μm) measured by Coulter Counter, and a tribo value of -19 pc/g measured by blow-off method against iron powder (20i/300 mesh). Further, when visually inspected using a microscope, although the pigment was dispersed in each toner particle, some aggregates of pigment were observed in the particles. A polymerized toner was obtained in the same manner as in Example 1 except that untreated quinacridone magenta (C, I. Pigment Red 122) was used as the pigment. The obtained toner had a volume average particle diameter of 11.2 gm (aperture diameter 100 p@) by Coulter Counter, and a tribo value of -18 μc/g by blow-off method against iron powder (200/300 mesh). Further, when visually inspected using a microscope, although the pigment was dispersed in each toner particle, some aggregates of pigment were observed in the particles. Effects of the Invention As described above, according to the present invention, since the dispersibility of the colorant is extremely good, a polymerized color toner having excellent spectral reflection characteristics, color mixing properties, and transparency can be obtained.

[Brief explanation of drawings]

FIG. 1 shows a schematic diagram of an apparatus for performing plasma processing. l...Motor 2...High frequency power supply 3...
High frequency supply electrode

Claims (2)

[Claims] (1) In a polymerized color toner obtained by suspension polymerizing a monomer system containing at least a colorant in an aqueous medium,
The coloring agent is an organic pigment having the general formula R-N=C=O (1) (wherein R is an alkyl group or alkenyl group having 1 to 20 carbon atoms containing no active hydrogen, or N, S , O, an alkyl group or alkenyl group having 1 to 20 carbon atoms and containing at least one halogen atom and not containing active hydrogen. Polymerized color toner. (2) In a method for producing a polymerized color toner by suspension polymerizing a monomer system containing at least a colorant in an aqueous medium, an organic pigment is used as the colorant, and the organic pigment has the general formula R-N =C=O(1) (wherein R is an alkyl group or alkenyl group having 1 to 20 carbon atoms that does not contain active hydrogen, or contains at least one of N, S, O, or a halogen atom, and contains no active hydrogen. 1. A method for producing a polymerized color toner, characterized by carrying out a treatment with an isocyanate ester represented by (representing an alkyl group or alkenyl group having 1 to 20 carbon atoms).