KR101255627B1 - Polymerized Toner and Method of Producing the same - Google Patents

Abstract

The present invention relates to a polymerized toner and a method for preparing the polymerized toner, the polymerized toner comprising a pigment and a pigment dispersant, wherein the pigment dispersant is represented by the formula (1) According to the present invention, it is possible to provide a method for producing a polymerized toner capable of realizing high image density (ID) with a uniform image.

[Formula 1]

Wherein R is OCH ₃ , CH ₃ , H, F, Cl or CF ₃ , R 'is an alkyl group having 1 to 5 C, R''is an alkyl group having 1 to 5, and R''' is 1 Is an alkylene group of ˜3, X is F or Cl, and the ratio of n: m is 1:10 to 10: 1 and n and m are each an integer of 5 to 100.)

 Polymerization toner, pigment dispersant, volume average particle diameter, transfer efficiency, burn

Description

Polymerized Toner and Method of Producing Them {Polymerized Toner and Method of Producing the same}

The present invention relates to a polymerized toner and a method for producing the polymerized toner, and more particularly, to a method for producing a polymerized toner which can realize a high ID and at the same time by using a specific pigment dispersant.

Toner is used in electrophotographic development, electrostatic printers, copiers, and the like, and refers to a paint that can be transferred to and fixed on a transfer object to form a desired pattern. Recently, as document creation using a computer is becoming more common, the demand for an image forming apparatus such as a printer is rapidly increasing, and thus the amount of toner is also increasing.

As a method of manufacturing the toner, there are a manufacturing method using pulverization and a manufacturing method using polymerization. The most widely known method of manufacturing using pulverization is to prepare toner particles by melting and mixing the resin and pigment together through melt-mixing process, pulverizing and extruding, pulverizing and classifying. However, the toner particles produced by this process have a problem of poor chargeability or flowability because the toner particles have a very irregular shape such as wide particle size distribution and pointed edges.

In order to solve this problem, a method of producing spherical toner particles by a polymerization method has been proposed. The polymerization method of toner by the polymerization method is known as emulsion polymerization / aggregation method and suspension polymerization method. Since emulsion polymerization method is difficult to control the size distribution of particles and there is a problem in the reproducibility of the quality of the produced toner, Processes by polymerization are preferred.

However, the polymerized toner particles formed by suspension polymerization exhibits a problem of uneven image and deterioration of ID when the pigment is not uniformly dispersed in the toner.

The present invention has been made to solve the above problems, by adding a pigment dispersant to the monomer mixture to uniformly disperse the pigment in the toner particles, a method of producing a polymerized toner that can realize a high ID with a uniform image Its purpose is to provide.

The present invention is to achieve the above object, in the polymerized toner comprising a pigment and a pigment dispersant, the pigment dispersant provides a polymerized toner, characterized in that used by the formula (1).

[Formula 1]

Wherein R is OCH ₃ , CH ₃ , H, F, Cl or CF ₃ , R 'is an alkyl group having 1 to 5 C, R''is an alkyl group having 1 to 5, and R''' is 1 Is an alkylene group of ˜3, X is F or Cl, and the ratio of n: m is 1:10 to 10: 1 and n and m are each an integer of 5 to 100.)

In addition, the pigment dispersant is characterized in that the weight average molecular weight of 2,000 ~ 200,000.

The polymerized toner core may be prepared by polymerizing a monomer mixture including a binder resin monomer and a charge control agent.

The binder resin monomer may be an aromatic vinyl monomer, an acrylate monomer, a methacrylate monomer, a diene monomer, or a mixture thereof.

In addition, the binder resin monomer is characterized in that it further comprises an acidic olefin monomer or a basic olefin monomer.

In addition, the charge control agent is an acid dye of nigrosine type, high aliphatic metal salt, alkoxy amine, chelate, quaternary ammonium salt, alkylamide, fluorine treatment active agent, metal salt of naphthalene acid, acid organic complex, chlorinated paraffin, chlorinated polyester , A polyester containing an acid, sulfonylamine of copper phthalocyanine, a styrene-acrylic polymer containing a sulfonic acid group, or a mixture thereof.

In addition, the monomer mixture is characterized in that it further comprises at least one additive selected from the group consisting of a wax, a crosslinking agent, a molecular weight regulator and a reaction initiator.

In addition, the wax is characterized in that the paraffin wax, microcrystalline wax, ceresin wax, carnuba wax, ester wax, polyethylene wax, polypropylene wax or a mixture thereof.

In addition, the crosslinking agent is divinylbenzene, ethylene dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, 1,6-hexamethylene diacrylate, allyl methacrylate, 1,1,1- Trimethylolpropane triacrylate, triallylamine, tetraallyloxyethane or a mixture thereof.

In addition, the molecular weight modifier is characterized in that t-dodecyl mercaptan, n-dodecyl mercaptan, n-octyl mercaptan, carbon tetrachloride, carbon tetrabromide or mixtures thereof.

In addition, 1 to 60 parts by weight of monomer for binder resin, 0.1 to 30 parts by weight of wax, 0.001 to 10 parts by weight of crosslinking agent, 0.1 to 20 parts by weight of charge control agent, 0.001 to 8 parts by weight of molecular weight regulator, 0.01 to 5 parts by weight of reaction initiator, It is characterized in that it comprises 2 to 10 parts by weight of the pigment and 0.5 to 5 parts by weight of the pigment dispersant.

In addition, the present invention comprises the steps of mixing the dispersion stabilizer with water to prepare an aqueous dispersion; Homogenizing the monomer mixture of claim 3 in the aqueous dispersion to disperse the monomer mixture in the form of fine droplets in the aqueous dispersion; Polymerizing the homogenized monomer mixture; And it provides a polymerized toner manufacturing method comprising the step of washing, drying the polymerized polymerized toner core.

In addition, the aqueous dispersion is characterized in that 1 to 10 parts by weight of the dispersion stabilizer is added to 100 parts by weight of water to make an aqueous dispersion.

In addition, the dispersion stabilizer is a water-soluble polyvinyl alcohol (PVA) having a degree of polymerization of 1,500 to 2,500, saponification of 75 to 98%.

According to the present invention, by using a specific pigment dispersant to increase the dispersibility of the pigment, it is possible to produce a polymerized toner having a uniform image and a high ID.

The present invention is to homogenize the monomer mixture and the aqueous dispersion containing the pigment and the pigment dispersant and to polymerize the homogenized monomer mixture to form a polymerized toner core, washing and drying to prepare a polymerized toner core, wherein the pigment dispersant is It is characterized by using the one indicated by 1.

[Formula 1]

Wherein R is OCH ₃ , CH ₃ , H, F, Cl or CF ₃ , R 'is an alkyl group having 1 to 5 C, R''is an alkyl group having 1 to 5, and R''' is 1 Is an alkylene group of ˜3, X is F or Cl, and the ratio of n: m is 1:10 to 10: 1 and n and m are each an integer of 5 to 100.)

The monomer mixture may be used by mixing a monomer for a binder resin, a charge control agent and the like.

As the monomer for the binder resin, an aromatic vinyl monomer, an acrylate monomer, a methacrylate monomer, a diene monomer, or a mixture thereof may be used, and optionally an acidic or basic olefin monomer may be used. In addition, 0.01 to 10 parts by weight of one or more selected from polyester-based and styrene acrylic polar polymers may be added to the monomer mixture.

Styrene, monochlorostyrene, methyl styrene, dimethyl styrene, etc. can be used as an aromatic vinylic monomer, It is preferable to use these at 30-95 weight part with respect to monomer total.

As the acrylate monomer, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, and the like can be used. As the methacrylate monomer, methyl Methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, etc. can be used, and butadiene, isoprene, etc. Can be used.

It is preferable that at least one of the acrylate monomer, the methacrylate monomer and the diene monomer is used in an amount of 5 to 70 parts by weight based on the total monomers.

As the acidic olefinic monomers, α, β-ethylenically unsaturated compounds having a carboxyl group can be used, and the basic olefinic monomers include methacrylic acid esters, methacrylamides and vinyls of aliphatic alcohols having amine groups or quaternary ammonium groups. An amine type, diallyl amine type, ammonium salt thereof, etc. can be used. When using one or more of the acidic or basic olefinic monomers, it is preferable to use 0.1 to 30 parts by weight based on the total monomers.

The dispersion stabilizer used in the present invention uses polyvinyl alcohol (PVA), and is dispersed in water to produce an aqueous dispersion.

The water-soluble polyvinyl alcohol (PVA) has a degree of polymerization of 1,500 to 2,500 and preferably 1,700 to 2,100. The saponification degree of the water-soluble polychloride alcohol (PVA) is 75 to 98%, preferably 85 to 95%. When the degree of polymerization of polyvinyl alcohol (PVA) is less than 1,500, it is difficult to sufficiently disperse the monomer mixture in the aqueous dispersion. When the degree of polymerization of polyvinyl alcohol (PVA) exceeds 2,500, the polyvinyl chloride (PVA) The solubility is lowered, making it difficult to produce a uniform aqueous dispersion. If the saponification degree of polyvinyl chloride (PVA) is less than 75%, the solubility of polyvinyl alcohol (PVA) decreases when the temperature is raised to the reaction temperature (60 ° C, 90 ° C), so that the monomer mixture may be properly dispersed. If the saponification degree exceeds 98%, the hydrophilicity of polyvinyl chloride (PVA) increases, and the performance as a dispersant is lowered. The content of water-soluble polyvinyl alcohol (PVA) is 1 to 10 parts by weight based on 100 parts by weight of the aqueous dispersion. Add.

Examples of the charge control agent include cationic charge control agents, acidic organic complexes, and chlorinated paraffins such as nigrosin-type acid dyes, high aliphatic metal salts, alkoxy amines, chelates, quaternary ammonium salts, alkylamides, fluorinated activators and metal salts of naphthalene acid. Anionic charge regulators or mixtures thereof, such as chlorinated polyesters, polyesters containing excess acid, sulfonylamines of copper phthalocyanine, styrene-acrylic polymers containing sulfonic acid groups, or mixtures thereof. It is preferable to use in an amount of 0.1 to 20 parts by weight with respect to.

As the pigment used in the present invention, a pigment generally used may be used, and for example, carbon black, Phthalocyanine-based cyan pigment, quinacridone-based or naphtol-based magenta ( Magenta pigment, Azo condensation (Azo condensation) or Pteridine or Diarylide (Yellow) Yellow pigments selected from one or more may be used. The amount of the pigment may be used in an amount of 2 to 10 parts by weight based on the total monomers (or the total amount of the polymerized toner).

The pigment dispersant used in the present invention uses those represented by the following formula (1).

[Formula 1]

Wherein R is OCH ₃ , CH ₃ , H, F, Cl or CF ₃ , R 'is an alkyl group having 1 to 5 C, R''is an alkyl group having 1 to 5, and R''' is 1 Is an alkylene group of ˜3, X is F or Cl, and the ratio of n: m is 1:10 to 10: 1 and n and m are each an integer of 5 to 100.)

Preferably, the pigment dispersant has a weight average molecular weight of 2,000 to 200,000. If the weight average molecular weight is less than 2,000, it is not preferable to generate fine granules during homogenization, and if it exceeds 200,000, the pigment dispersant does not dissolve well in the monomer mixture. Therefore, it is not preferable. The pigment dispersant is used in an amount of 0.5 to 5 parts by weight based on 100 parts by weight of the total monomers, but if less than 0.5, it is not preferable because it is difficult to obtain the dispersion effect of the pigment in an insufficient amount, if it exceeds 5 parts by weight excessively the viscosity of the monomer mixture It is not desirable to increase the droplets with a large average particle diameter in the homogenization step.

In addition, in the above formula, the ratio of n and m is preferably in the range of 1:10 to 10: 1. If the ratio is out of the above range, it may have a dispersing effect on a specific pigment, but obtains a dispersing effect on all the types indicated above. This is because it is difficult because it is difficult.

The present invention may further comprise at least one additive selected from the group consisting of wax, crosslinking agent, molecular weight regulator and reaction initiator, in addition to the above components, the binder resin monomers and pigments, pigment dispersants and monomers including the additives It is called a mixture.

As said wax, Petroleum refined wax, such as a paraffin wax, a microcrystal wax, a ceresin wax; Natural waxes such as carnuba wax; Or synthetic waxes such as ester waxes, polyethylene waxes, and polypropylene waxes. The wax is preferably used in 0.1 to 30 parts by weight based on the total monomers.

As the crosslinking agent, divinylbenzene, ethylene dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, 1,6-hexamethylene diacrylate, allyl methacrylate, 1,1,1-trimethylol Propane triacrylate, triallylamine, tetraallyloxyethane and the like are used, and it is preferable to use 0.001 to 10 parts by weight based on the total monomers.

As the molecular weight modifier, t-dodecyl mercaptan, n-dodecyl mercaptan, n-octyl mercaptan, carbon tetrachloride and carbon tetrabromide may be used, and these molecular weight modifiers may be used in an amount of 0.001 to 8.000 based on the total monomers. It is preferable to use by weight part.

The reaction initiator may further include 0.01 to 5 parts by weight based on the total monomers. As the reaction initiator, an oil-soluble initiator and a water-soluble initiator can be used. Specifically, Azo initiators, such as azobisisobutyronitrile and azobisvaleronitrile; Organic peroxides such as benzoyl peroxide and lauroyl peroxide; Generally used water-soluble initiators, such as potassium persulfate and ammonium persulfate, etc. can be used. The reaction initiator is preferably used in an amount of 0.01 to 5.00 parts by weight, and more preferably 0.1 to 2.0 parts by weight, based on the total monomers.

The present invention comprises the steps of mixing the dispersion stabilizer with water to prepare an aqueous dispersion;

Homogenizing the monomer mixture by dispersing it in an aqueous dispersion;

Polymerizing the homogenized monomer mixture; And

Characterized by a method for producing a polymerized toner comprising the step of washing and drying the polymerized polymerized toner core.

One embodiment of the present invention includes the following suspension polymerization step.

(1) Polymerized Toner Manufacturing Step

A water-based polyvinyl alcohol (PVA) is dispersed in an aqueous solution to prepare an aqueous dispersion, and the monomer mixture is added to the aqueous dispersion to homogenize by applying a shear force to a homogenizer, followed by polymerization to prepare a toner core.

The monomer mixture uses aromatic vinyl monomers, acrylate monomers, methacrylate monomers, diene monomers or mixtures thereof and optionally acidic or basic olefin monomers, pigments, pigment dispersants and other additives described above.

 (2) polyvinyl alcohol (PVA) removal step

In the solution containing the polymerized toner prepared above, first, polyvinyl alcohol (PVA) is separated from the toner by a suitable method. After diluting the aqueous dispersion containing polyvinyl alcohol (PVA) containing the polymerized toner by adding distilled water twice the total weight, applying shear force with a homogenizer, the filter device, the filter press device, and the general centrifugation The water-soluble polyvinyl alcohol (PVA) can be separated from the toner through a separation and washing process using a separation device, a continuous deconverter type high speed centrifugal device, or the like. Finally, water is removed through filtering, the toner cake is put in a vacuum oven, and vacuum dried at room temperature to prepare a polymerized toner core.

In order to describe the present invention in more detail, the following examples are described, but for the purpose of thorough understanding and disclosure of the present invention, the present invention is not limited thereto.

Example 1

(Production of Polymerized Toner)

After adding 5 parts by weight of a water-soluble polyvinyl alcohol (polymerization degree 1700, saponification degree 90%) as a dispersant to 400 parts by weight of ion-exchanged water, after stirring for 10 minutes at room temperature, the temperature was raised to 70 ℃ the reaction temperature and stirred again for 20 minutes The dispersion was prepared.

160 parts by weight of styrene, 36 parts by weight of n-butyl acrylate and 4 parts by weight of acrylic acid were used as monomers, 4 parts by weight of allyl methacrylate as a crosslinking agent, 0.4 parts by weight of n-dodecyl mercaptan as a molecular weight regulator, and a sulfonic acid group After fully dissolving 1 part by weight of a styrene-acrylic polymer charge controlling agent including 4 parts by weight of a Phthalocyanine-based Cyan pigment, a weight average molecular weight of 100,000 and a pigment dispersant having a weight ratio of 1 to 1 in Formula 1, wherein 2 parts by weight of the mixture was added, and the mixture was stirred at 2,000 rpm for 2 hours with a bead mill, and beads were removed to finally prepare 215 parts by weight of the monomer and pigment mixture.

After the mixture was heated to 70 ° C. in a water bath, 5 parts by weight of paraffin wax was added thereto, followed by stirring for 20 minutes, and then the reaction was continued for 15 hours at 600 rpm with a paddle type stirrer to prepare a polymerized toner.

(Cleaned by centrifuge)

After diluting the aqueous dispersion containing polyvinyl alcohol (PVA) containing the polymerized toner synthesized above by adding distilled water twice the total weight, applying shear force with a homogenizer, the centrifugal separator (Beckman J2- Centrifuge for 15 minutes at 3,000 rpm using 21M, Rotor JA-14). After diluting the distilled water by adding 2 times distilled water to the concentrate containing the polymerized toner, applying shear force with a homogenizer and centrifuging at 3,000 rpm for 15 minutes using a centrifugal separator (Beckman J2-21M, Rotor JA-14). The separation process was repeated two more times to remove polyvinyl alcohol (PVA) from the toner surface. Finally, water was removed through filtering, the toner cake was put in a vacuum oven, and vacuum dried at room temperature for 48 hours to prepare a toner.

[Example 2]

In Example 1, the polymerization toner was obtained in the same manner as in Example 1 except that the ratio of m and n of the pigment dispersant was 1: 3. The evaluation results are shown in Table 1.

[Example 3]

In Example 1, the polymerization toner was obtained in the same manner as in Example 1 except that the ratio of m and n of the pigment dispersant was 3: 1. The evaluation results are shown in Table 1.

Example 4

In Example 1, the polymerization toner was obtained in the same manner as in Example 1 except that the weight part based on the monomer mixture of the pigment dispersant was 1. The evaluation results are shown in Table 1.

Comparative Example 1

In Example 1, the polymerization toner was obtained in the same manner as in Example 1 except that the pigment dispersant was not added. The evaluation results are shown in Table 1.

Comparative Example 2

In Example 1, the polymerization toner was obtained in the same manner as in Example 1 except that the ratio of m and n of the pigment dispersant was 1:20. The evaluation results are shown in Table 1.

[Comparative Example 3]

In Example 1, the polymerization toner was obtained in the same manner as in Example 1 except that the ratio of m and n of the pigment dispersant was 20: 1. The evaluation results are shown in Table 1.

[Experimental Example]

(Size and shape of toner particles)

The size and shape of the produced toner particles were all measured and observed by using a multisizer cooler counter and SEM.

(Consumption and Transfer Rate of Toner)

Fill the surface-treated toner of the HP4600 printer (Hewlett-Packard) printer cartridge with the surface-treated toner, weigh the entire study, print 1,000 square sheets of 19 cm by 1.5 cm on A4 paper, and then measure the weight of the supply again to consume the toner. Was calculated.

Consumption (g) = 1,000 sheets before printing Supplier  Weight-After 1,000 sheets print Supplier  weight

The weight of the drum portion that can be separated from the supply portion was measured before printing and after printing to calculate the amount of toner that was not transferred and wasted.

Wasted Amount of toner (g) = After 1,000 copies Drum  Weight-1,000 sheets before printing Drum  weight

From the amount of toner consumed and wasted, the transfer rate was calculated by the following equation.

% Transfer = {(consumption-wasted Amount of toner ) / Consumption} * 100

The results are shown in Table 1.

(Image Density)

ID was measured with Macbeth RD918 Image Density meter.

(Image uniformity)

Image uniformity is that after printing the entire surface of A4 paper and dividing the front printed part evenly into 16 parts, measuring the image density of each part and judged that the image is uniform when the standard deviation of the measured value is not larger than 1/20 of the average. It was.

Pigment Dispersant Volume average particle diameter (dv) Volume average particle size / number average particle diameter (dv / dp) Toner Consumption (g) Toner Transfer Rate (%) ID (Image Density) Image uniformity Example 1 2 7.2 1.25 19 94 1.5 Uniformity 2 2 7.3 1.26 20 95 1.4 Uniformity 3 2 7.2 1.25 19 94 1.4 Uniformity 4 One 6.8 1.26 18 95 1.4 Uniformity Comparative Example 1 0 6.8 1.40 28 65 1.1 Not uniform 2 2 7.2 1.26 20 94 1.2 Not uniform 3 2 7.3 1.27 19 94 1.2 Not uniform

Claims (14)

In the polymerized toner containing a pigment and a pigment dispersant, the pigment dispersant may be represented by the following formula (1), The polymerized toner includes a polymerized toner core prepared by polymerizing a monomer mixture including a binder resin monomer and a charge control agent. The pigment dispersant is 0.5 to 5 parts by weight based on 100 parts by weight of the monomer mixture. [Formula 1]

Wherein R is OCH ₃ , CH ₃ , H, F, Cl or CF ₃ , R 'is an alkyl group having 1 to 5 C, R''is an alkyl group having 1 to 5, and R''' is 1 Is an alkylene group of ˜3, X is F or Cl, and the ratio of n: m is 1:10 to 10: 1 and n and m are each an integer of 5 to 100.) The method of claim 1, The pigment dispersant is a polymerized toner, characterized in that the weight average molecular weight of 2,000 ~ 200,000. delete The method of claim 1, The binder resin monomer is an aromatic vinyl monomer, an acrylate monomer, a methacrylate monomer, a diene monomer, or a mixture thereof. 5. The method of claim 4, The binder resin is a polymerized toner further comprising an acidic olefin monomer or a basic olefin monomer. The method of claim 1, The charge control agent is a nigrosin-type acid dye, a high aliphatic metal salt, alkoxy amine, chelate, quaternary ammonium salt, alkylamide, fluorine treatment active agent, metal salt of naphthalene acid, acid organic complex, chlorinated paraffin, chlorinated polyester, acid Polymerized toner, characterized in that the polyester containing, sulfonylamine of copper phthalocyanine, styrene-acrylic polymer containing a sulfonic acid group, or a mixture thereof. The method of claim 1, The monomer mixture further comprises one or more additives selected from the group consisting of waxes, crosslinkers, molecular weight regulators and reaction initiators. 8. The method of claim 7, The wax is a paraffin wax, microcrystalline wax, ceresin wax, carnuba wax, ester wax, polyethylene wax, polypropylene wax, or a mixture thereof. 8. The method of claim 7, The crosslinking agent is divinylbenzene, ethylene dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, 1,6-hexamethylene diacrylate, allyl methacrylate, 1,1,1-trimethylol Polymerized toner, characterized in that propane triacrylate, triallylamine, tetraallyloxyethane or a mixture thereof. 8. The method of claim 7, The molecular weight regulator is a t-dodecyl mercaptan, n-dodecyl mercaptan, n-octyl mercaptan, carbon tetrachloride, carbon tetrabromide or a mixture thereof. 8. The method of claim 7, 1 to 60 parts by weight of monomer for binder resin, 0.1 to 30 parts by weight of wax, 0.001 to 10 parts by weight of crosslinking agent, 0.1 to 20 parts by weight of charge control agent, 0.001 to 8 parts by weight of molecular weight regulator, 0.01 to 5 parts by weight of reaction initiator, pigment 2 Polymerized toner, characterized in that it comprises ~ 10 parts by weight and 0.5 to 5 parts by weight of the pigment dispersant. Mixing the dispersion stabilizer with water to prepare an aqueous dispersion; Homogenizing the monomer mixture of claim 1 in the aqueous dispersion to disperse the monomer mixture in the form of fine droplets in the aqueous dispersion; Polymerizing the homogenized monomer mixture to form a polymerized toner core; And Polymerized toner manufacturing method comprising the step of washing and drying the polymerized polymerized toner core, The polymerized toner includes a pigment and a pigment dispersant, The pigment dispersant may be represented by Formula 1 below, wherein the pigment dispersant is 0.5 to 5 parts by weight based on 100 parts by weight of the monomer mixture. [Formula 1]

Wherein R is OCH ₃ , CH ₃ , H, F, Cl or CF ₃ , R 'is an alkyl group having 1 to 5 C, R''is an alkyl group having 1 to 5, and R''' is 1 Is an alkylene group of ˜3, X is F or Cl, and the ratio of n: m is 1:10 to 10: 1 and n and m are each an integer of 5 to 100.) 13. The method of claim 12, The aqueous dispersion is a polymerized toner producing method, characterized in that for adding 1 to 10 parts by weight of a dispersion stabilizer to 100 parts by weight of water to make an aqueous dispersion. 13. The method of claim 12, Wherein said dispersion stabilizer is a water-soluble polyvinyl alcohol (PVA) having a degree of polymerization of 1,500 to 2,500 and a degree of saponification of 75 to 98%.