JPH04156555A - Manufacture of toner for developing electrostatic charge image - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a toner, and more specifically, a method for producing a toner with excellent fluidity, chargeability, and resolution for use in electrostatic charge development by a polymerization method. Regarding.

[Conventional technology]

The toner used for developing electrostatic latent images in electrophotography is produced using a pulverization method in which a low melting point resin is mixed with colorants such as carbon black, dyes and pigments, and a charge control agent, and then pulverized and classified. Manufactured. - The average particle size of the toner manufactured by the pulverization method for boat fishing is 10 to 15 μm,
Its particle size distribution is in the range of 1 to 30 μm. In order to obtain even smaller particles with a narrower distribution from this range, it is necessary to carry out a precise classification process, but the cost is extremely high due to the labor involved in the classification process and the reduction in classification yield, which poses a problem from an economic point of view. . In addition, when manufacturing using the cross-wire pulverization method, it is extremely difficult to uniformly disperse and add internal additives such as colorants and charge control agents that are added to low-melting point resins. performance, and in particular causes unevenness in images and printability due to non-uniform charge. Furthermore, in the case of the pulverization method, the shape after pulverization is amorphous, resulting in a mixture of various shapes. Therefore, the correlation between the chargeability and image of each individual particle and the average particle size and particle size distribution becomes unclear, resulting in a product that lacks reproducibility due to performance fluctuations between lofts.

Various methods have been attempted to improve the drawbacks of these pulverization methods. As the most representative method, a method for producing a developer using a polymerization method has been proposed.

As a method for producing a dry toner by a polymerization method, an emulsion polymerization method in an organic solvent can be mentioned, for example, Japanese Patent Application Laid-Open Nos. 61-273552 and 61-273553. All methods have the drawbacks of using an organic solvent for the reaction, requiring a long time to form particles, and having a broad particle size distribution.

Examples of the suspension polymerization method include JP-A-61-22354 and JP-A-61-67039. In either method, a homomixer that utilizes shearing force from high-speed rotating blades during suspension is used as the suspension means. Although this method is effective in shearing the polymerized monomer, which is the main component, it is inferior in that it produces particles with a uniform particle size distribution, and the particle size distribution of the product becomes broad. Another drawback is that it is difficult to uniformly disperse the additives and other additives to be added internally to the polymerized monomer.

JP-A No. 63-113561 proposes a method of treating a dispersion liquid and a polymerized monomer in the dispersion liquid using a high-pressure homogenizer for the purpose of reducing the diameter and narrowing the distribution of particles. ing. The working mechanism of this pressure-type homogenizer is that the pressurized processing liquid flows into the low-pressure section through a controlled micro-gap and collides with a collision member, such as an impact ring, installed in the low-pressure section, causing shearing. It is something. However, even in this method, the diameter of the generated particles is 5 to 16 μm.
Do you have 9 items within the range and 90 original items? A turbidity was not obtained,
It is difficult to obtain a narrow distribution product with an average particle diameter of 5 to 9 μm, and a classification step is required to obtain a small particle size narrow distribution product, and if the classification step is required, the cost will be increased.

[Problem that the invention seeks to solve]

The purpose of the present invention is to produce a toner for developing electrostatic images using a suspension polymerization method, which has an average particle diameter of 5 to 9 μm suitable for high resolution, has an extremely narrow particle size distribution, and has no internally added additives. An object of the present invention is to provide a toner production method that can efficiently produce uniformly dispersed toner.

[Means for Solving the Problems] As a result of extensive research into the suspension method used in the production of toner using the suspension polymerization method described above, the present inventors found that the type and amount of the dispersant in the dispersion liquid, and the main component By carrying out collision treatment of the suspension itself as a suspending means under conditions in which the ratio of water in the dispersion to the polymerized monomer is within a specific range, arbitrary average particles of 5 to 9 μm can be produced. diameter and an extremely narrow particle size distribution, resulting in particles with a uniform composition in which various additives are evenly dispersed within the generated particles, making it possible to stably produce high-performance toner for electrostatic charge development with high productivity and at low cost. I found a way to do it.

That is, in the present invention, at least a polymerizable monomer, a colorant, a charge control agent, and other small amounts of internal additives are predispersed in advance using a high-speed stirrer or the like, and then the predispersion is mixed with water, a surfactant, and It is added to the dispersion medium of the dispersion stabilizer and pre-suspended using a high-speed stirrer such as a TK homomixer to form oil droplets with an average particle size of 30 to 40 pm. The presuspension is then processed using a liquid-liquid emulsifier, such as a US
Biotechnology described in P4.533,254 publication
Equipment manufactured by Development Corporation (product name,
Microfluidizer M type), 1,000 ~
By processing under a pressure of 15.0 OOP SI, 5
It is possible to generate oil droplets with an arbitrary diameter of ~9 μm and an extremely narrow particle size distribution, and the colorant, charge control agent, and other internal additives are uniformly dispersed in the oil droplets. The result was a particle with a similar composition.

As for the composition of the suspension according to the present invention, water is 3.5 to 6 times the weight of the polymerizable monomer, and surfactants are each c, m, c,
The dispersion stabilizer is 0.5 to 2.0 times the concentration of water.
．． It has the characteristic that it exhibits its effect in the range of 5 to 3.5% by weight. Next, the suspension liquid used in the present invention is subjected to a heating polymerization reaction using a conventional method. However, during the polymerization reaction process, the diameter and distribution of the particles formed during suspension, as well as the dispersion state of the internal additives, etc., may be changed. No 0
After the polymerization reaction is completed, the surfactant and dispersion stabilizer can be removed by washing with water or the like, and the toner powder can be obtained by drying.

The polymerizable monomer used in the present invention is a monomer having a CH,=C group, and includes the following monomers.

Namely, styrene, 0-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4
-dichlorostyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-te
rt-butylstyrene, p-n-hexylstyrene, p
-n-octylstyrene, p-n-nonylstyrene, p
- Styrene and its derivatives such as n-decylstyrene and p-n-dodecylstyrene; ethylene, propylene,
Ethylene and unsaturated monoolefins such as butylene and isobutylene; Vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl fluoride; Vinyl esters such as vinyl acetate, vinyl propionate, and vinyl benzoate: Methacrylate Methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate,
α-Methylene aliphatic monocarboxylic acids such as isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, etc. Esters: Methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, acrylic acid Stearyl, acrylic acid-2-
Acrylic acid esters such as chloroethyl and phenyl acrylate; Maleic acid and maleic acid half ester; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether; Vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone, etc. Vinyl ketones: N-vinylvirol,
N-vinylcarbazole, N-vinylindole, N-
Examples include N-vinyl compounds such as vinylpyrrolidone; vinylnaphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide; these may be used alone or in combination. Among these, it is preferable to use styrene or a styrene derivative alone or in combination with other monomers as the polymerizable monomer from the viewpoint of development characteristics and durability.

In order to improve fixing properties and offset resistance when fixed to a hot pressure roller, the monomer composition contains waxes such as paraffin wax, and release properties such as low molecular weight polyolefins such as low molecular weight polyethylene and low molecular weight polypropylene. It is preferable to add a low softening point compound having the following properties.

In that case, the amount added is 1 to 30 parts by weight per 100 parts by weight of the polymerizable monomer.

, Low softening point compounds include paraffin, wax,
Low molecular weight polyolefins, modified waxes with aromatic groups, hydrocarbon compounds with alicyclic groups, natural waxes, long hydrocarbon chains with 12 or more carbon atoms (CH, -÷CHz+r
Examples include long-chain carboxylic acids having an aliphatic carbon chain of r or +cH2→n or more, esters thereof, and the like. A mixture of different low softening point compounds may be used. Specifically, paraffin wax (manufactured by Nippon Oil), micro wax (manufactured by Nippon Oil), microcrystalline wax (manufactured by Nihon Jyutsu), hard paraffin wax (manufactured by Nippon Jyutsu), and PE.
-130 (manufactured by Hoechst), Mitsui Hiwax ll0P (
Mitsui Hiwax 220P (Mitsui Petrochemical), Mitsui Hiwax 660P (Mitsui Petrochemical), Mitsui Hiwax 210P (Mitsui Petrochemical), Mitsui Hiwax 320P (Mitsui Petrochemical),
Mitsui Hiwax 410P (Mitsui Petrochemicals), Mitsui Hiwax 420P (Mitsui Petrochemicals), Hilets T-100X (Mitsui Petrochemicals), Hilets T-20
0X (manufactured by Mitsui Petrochemicals), Highlets T-300X (manufactured by Mitsui Petrochemicals): Vetrogin 80 (manufactured by Mitsui Petrochemicals)
, Vetrogin 100 (Mitsui Petrochemicals), Vetrogin 120 (Mitsui Petrochemicals), Tac Ace A-100
(manufactured by Mitsui Petrochemicals), Tac Ace F-100 (manufactured by Mitsui Petrochemicals), Tac Ace B-60 (manufactured by Mitsui Petrochemicals), modified wax JC-1141 (manufactured by Mitsui Petrochemicals),
Modified wax JC-2130 (Mitsui Petrochemical), modified wax JC-4020 (Mitsui Petrochemical), modified wax JC-11,42 (Mitsui Petrochemical), modified wax JC-5020 (Mitsui Petrochemical), Viscole 55
0P (manufactured by Sanyo Chemical), Viscol 660P (manufactured by Sanyo Chemical), Viscoal TS-200 (manufactured by Sanyo Chemical), Saniwax 151P (manufactured by Sanyo Chemical), beeswax, carnauba wax, montan wax, candelilla wax, etc. I can do it.

In order to produce a crosslinked polymer, the following crosslinking agent may be present in the monomer composition and suspension polymerization may be carried out. especially,
When a polymer, copolymer or cyclized rubber is not added to the monomer composition, it is particularly preferable to add it.

Divinylbenzene, divinylnaphthalene, polyethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 1,3-butylene glycol dimethacrylate, 1
, 6-hexane gelicol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis(4-methacryloxyjetoxyphenyl)propane, 2,2'-bis( 4-
Common crosslinking agents such as acryloxyjetoxyphenyl)propane, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, dibromneopentyl glycol dimethacrylate, and diallyl phthalate can be used as appropriate.

If these crosslinking agents are used in a large amount, they will be difficult to melt by heat, resulting in poor heat fixing properties or heat pressure fixing properties. In addition, if the amount used is small, the blocking resistance required as a toner,
Properties such as durability deteriorate, and in hot roll fixing,
It becomes difficult to prevent an offset phenomenon in which a portion of the toner does not completely adhere to the paper and adheres to the roller surface and is transferred to the next paper. Therefore, the amount of these crosslinking agents used is preferably 0.1 to 10% by weight based on the polymerizable monomer.

The monomer composition contains a colorant, and colorants include conventionally known dyes, pigments, carbon black,
Pigments such as grafted carbon black, in which the surface of the carbon black is coated with a resin, can be used. The coloring agent is 0.1 to 20% by weight based on the polymerizable monomer.
Contains.

A charge control agent and a fluidity modifier may be added (internally added) to the toner as necessary. The charge control agent and the fluidity modifier may be used by being mixed (externally added) with the toner particles. Examples of the charge control agent include metal complexes of organic compounds having carboxyl groups or nitrogen-containing groups, metal-containing dyes, nigrosine, and alkylonium salts. Examples of fluidity modifiers or cleaning aids for the surface of the latent image carrier (photoreceptor) include colloidal silica and fatty acid metal salts. In addition, for the purpose of increasing the volume, fillers such as calcium carbonate and fine powdered silica are added by 0.5
It may be blended into the toner in a range of 20% by weight.

As a polymerization initiator, 2,2'-azobis-(2,4-
dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, l,1'-azobis(cyclohexane-
1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, and other azo or diazo polymerization initiators such as azobisisobutyronitrile (AIBN); benzoylper oxide,
Examples include peroxide polymerization initiators such as methyl ethyl ketone peroxide, isopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorylbensyl peroxide, and lauroyl peroxide.

Furthermore, a polar polymer or a polymer elastomer may be added during polymerization to improve the physical properties of the polymerized toner.

Next, it is necessary to stably suspend the oil layer containing the above-mentioned polymerized monomer as a main component in water to a desired particle size and particle size distribution. Examples of the dispersion stabilizer include polyvinyl alcohol, gelatin, methylcellulose, methylhydropropylcellulose, ethylcellulose, sodium salt of carboxymethylcellulose, polyacrylic acid and salts thereof, starch, gum alginate, zein, casein, tricalcium phosphate, Examples include talc, barium sulfate, bentonite, aluminum hydroxide, and ferric hydroxide. These dispersion stabilizers are related to the amount of surfactant used below and the amount of water in the polymerized monomer and suspension medium, which is the oil layer, and are 2.5 to 3.5% by weight based on the water.
is preferred.

Next, the surfactants used in combination with the dispersion stabilizer are sodium dodecylbenzenesulfonate, sodium tetradecyl sulfate, sodium pentadecyl sulfate,
Sodium octyl sulfate, sodium allyl-alkyl-polyether sulfonate, sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, 3.3-disulfonodiphenylurea- Sodium 4,4-diazo-bis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2.5.
Sodium 5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-disulfonate,
Others can be mentioned.

The optimal amount of these surfactants to be used is a concentration of 0.5 to 2.0 times the specific c, va, c, (critical micelle concentration) of each surfactant, based on the water used.

Next, the amount of water used during suspension is 3. 5 to 6 times the amount is suitable, and ion-exchanged water with little salt content is suitable.

In the present invention, after oil droplets are formed by suspension, polymerization is started from about 50°C by a conventional method, and finally the oil droplet is formed at about 95-100°C.
Complete the reaction at °C. After cooling, remove the dispersion stabilizer and surfactant, wash with water, dry at 40-50°C, and crush.
By treating with a surface treatment agent if necessary, a toner can be obtained in high yield.

The polymerized toner obtained by the production method of the present invention can be applied to a known dry electrostatic development method. In particular, it can be suitably used as a high-resolution toner that requires a sharp particle size distribution and a small particle size toner with an average particle size of 5 to 9 μm.

〔Example〕

The present invention will be further explained in detail with reference to Examples below, in which parts indicate important parts.

Example 1 206 parts of styrene monomer and 37 parts of 2-ethylhexyl acrylate were mixed with 12.1 parts of carbon black MA40 (manufactured by Mitsubishi Chemical Industries, Ltd.), 0.4 parts of divinylbenzene, and 4.8 parts of Viscoel 660P (manufactured by Sanyo Chemical Industries, Ltd.). Section, 2.2
-azobis(2,4-dimethyl)valeronitrile 7.3
1 part, 2.4 parts of azobisisobutyronitrile, and 4.8 parts of 1:2 type metal dye (trade name, Aizensviron Black TRH (manufactured by Hodogaya Chemical Industry)), and heated at 5 to 15 °C. 100 using TK homomixer (manufactured by Tokushu Kika Kogyo)
Pre-dispersion was carried out at 00 r, p, m for 20 minutes to prepare an oil layer containing the polymerized monomer as the main component.

Next, a dispersion medium containing 259 parts of 10% tricalcium phosphate solution (manufactured by Taihei Kagaku Sangyo ■) and 246 parts of 0.171% sodium dodecylbenzenesulfonate aqueous solution was prepared in 386 parts of ion-exchanged water. Add the oil layer and mix with a TK homomixer at 5-10°C for 3000r.
p, m, for 15 minutes, then 400 Or, p, in, for 2
Presuspension was performed for 0 minutes. The pre-suspension was processed using a microfluidizer M-110T (manufactured by Microfluidic, Inc., USA) using a back pressure module.
,000 PSI 4 buses were conducted. As a result, the oil droplet particles of the obtained suspension were measured using SK Laser Micronsizer PRO-70003 (manufactured by Yaishin Enterprise ■), and the average particle size was 8.5 μm, and the production rate of fine particles of 4 μm or less was 1.5%. , the production rate of coarse particles of 16 μm or more was 3%.

This suspension was transferred to an autoclave equipped with a stirrer and polymerized at 60° C. for 6 hours and at 90° C. for 1 hour, then cooled and the tribasic calcium phosphate was dissolved with hydrochloric acid. Filtration/washing,
After drying, the average particle size was 8°2 μm, and the particle size was 9 μm from 5 to 16 μm.
A narrow particle size toner having a particle size composition containing 5.5% was obtained. This toner was spherical and had no uneven color, and the triboelectric charge distribution with the iron powder carrier DSP-128 (manufactured by Dowa Iron Powder ■) was measured using an East Part Analyzer EST-1 model (manufactured by Hoiyo Micron ■). However, it showed a very sharp distribution of negative charges without reverse polarity. 40 parts of the above toner and iron powder carrier Z-2008 (manufactured by Powder Tenku ■) 960
After preparing the developer by mixing the
-508 (manufactured by Sanyo Electric Co., Ltd.) was used for printing evaluation, and a high-definition printed matter with high clarity and no fogging was obtained.

Comparative Example 1 Using the same composition as in Example 1 up to the pre-suspension, the main suspension treatment was carried out using a Gorlin homogenizer described in JP-A No. 63-113561 and 5M-8TA at 8,000P.
si, suspension treatment was carried out for 5 passes. The particles formed into oil droplets had an average particle size of 34.7 μm, and the production rate of coarse particles of 24 μm or more was 64%, and the particle size was large and the distribution thereof was broad. A polymerization reaction was carried out in the same manner as in the example to obtain a powder, which was prepared as a developer. When the print was evaluated using a laser printer 5FX-508, it lacked sharpness and fine line reproducibility, and fog was observed. It was done.

Example 2 194 parts of styrene monomer and 49 parts of n-butyl methacrylate were mixed with 12 parts of carbon black M-100 (Mitsubishi Chemical Industries), 0.4 part of divinylbenzene, and 55 parts of Viscole.
12 parts of 0P (manufactured by Sanyo Kasei Kogyo), 12 parts of Eisensubironburasoku TRH (manufactured by Hodogaya Chemical Industry), 7.3 parts of 2,2-azobis(2,4-dimethyl)valeronitrile, azobisisobutyronitrile 2.4 parts were added and dispersed in the same manner as in Example 1 to prepare an oil layer, and a dispersion medium was also prepared with the same composition as in Example 1. Next, homogenizer FIC-5000
(manufactured by Microfluidics, USA), the mixture of the oil layer and the dispersion medium was pre-suspended at 2,000 PSI. Pre-suspension is carried out using Microfluidizer-M
The main suspension treatment was carried out by performing three passes at -110T and 9,000 PSI. At that time, the average particle size of the oil droplet product in the suspension was 7.5 μm, the production rate of fine particles of 4 μm or less was 1.9%, and the production rate of coarse particles of 16 μm or more was 4%.

This suspension treatment solution was subjected to reaction and post-treatment in the same manner as in Example 1, and the average particle size was 7.3 μm and the particle size was 92 μm to 5-16 μm.
A toner with a sharp particle size distribution of % was obtained.

This toner was mixed with a carrier to form a developer in the same manner as in Example 1. Laser printer 5FX using this developer
-508 (manufactured by Sanyo Electric Corporation), a high-definition printed matter with high clarity and no fogging was obtained.

Comparative Example A pre-suspension liquid was prepared with the same composition and the same method as in Example 2, and the main suspension treatment was carried out using a known TK homo mixer (manufactured by Tokushu Kika Kogyo ■) at 8.00 Or, p, m, Suspension treatment was carried out for 30 minutes. The oil droplet particles generated by this suspension treatment have an average particle size of 9.2 μm, a production rate of fine particles of 4 μm or less: 15.2%, and a production rate of coarse particles of 25 μm or more: 1.
2%, and the particle size distribution was broad. This suspension was processed in the same manner as in Example 2 to obtain a toner. The obtained toner was used as a developer in the same manner as in Example 2, but the charge distribution of this developer was broad, and the printed matter produced by the printer was foggy and the print density was low, so that it could not be used for practical use.

Example 3 6 parts of nigrosine was used in place of Eisensviron Black T RH in Example 1, and suspension, polymerization, and post-treatment were carried out to obtain a positively charged toner.

The average particle size of the obtained toner was 8.0 pm, and 4
2% fine particles less than μm and coarse particles more than 16μm
The particle size distribution was very sharp. Prints produced by a printer using this toner had high resolution and high density without fogging.

Example 4 A yellow pigment (color index N! 121100) was used instead of the carbon black of Example 2, and zinc 3,4-jeta-shaributylsalicylate was used instead of Eisenspiron black TRH. A yellow toner was obtained by processing in the same manner as in Example 2.

This yellow toner has an average particle size of 7.2 μm, 4 μm or less,
The percentage of particles with a particle size of 16 μm or more was 2% or less. This toner was used as a yellow toner for full-color printers and copying machines, and produced prints and copies with high resolution, high density, and no fog.

Example 5 In place of the carbon black in Example 4, a red pigment (color index Nα74160) was used, and Example 4
A red toner was obtained by processing in the same manner as above.

The average particle size of this red powder was 7.3 μm, and it had a sharp particle size distribution in which particles of 4 μm or less and particles of 16 μm or more were both 1.5% or less. This developer of toner and carrier was used as a cyan toner for color printers and color copying machines, and produced prints and copies with high resolution, high density, and no fog.

Example 6 Instead of the carbon black in Example 1, 80 parts of magnetite (manufactured by Mitsui Mining & Co., Ltd.) was used and treated in accordance with Example 1 to obtain black powder. The average particle size of this powder is 7
．． The particle size was 1 μm, and the proportion of particles of 4 μm or less and particles of 16 μm or more were both 1% or less.

0.2% by weight of colloidal silica was added and mixed to this powder to prepare a -component dry type developer.

When a printing test was conducted using this developer with an LBP printer, clear printed matter with high resolution and high density without fogging could be obtained.

Example 7 A blue toner was obtained in the same manner as in Example 1 except that a blue pigment (Color Index Na74160) was used in place of the carbon black in Example 1. The average particle diameter of this toner is 6.4 μm, with fine particles of 4 μm or less and 16 μm.
A toner with a small particle size narrow distribution in which the content of coarse particles of μm or more was 2% or less was obtained.

This toner was mixed with a carrier to form a developer in the same manner as in Example 1, and in a printing test using a printer, prints with high resolution, high density, and no fog were obtained.

Claims (1)

[Claims] 1. A dispersion containing at least a polymerizable monomer, a colorant, a surfactant, a dispersion stabilizer, and water is prepared, and the dispersions are collided with each other under pressure to produce suspended particles. 1. A method for producing an electrostatic charge developing toner, which comprises producing and further polymerizing the toner. 2. The composition of the dispersion according to claim 1 is such that the water is 3.5 to 6 times the weight of the polymerizable monomer, and the surfactant is c. m. c. (
A method for producing a toner for electrostatic charge development, characterized in that the concentration of the dispersion stabilizer is adjusted to 0.5 to 2.0 times the critical micelle concentration (critical micelle concentration) and 2.5 to 3.5% by weight of the dispersion stabilizer based on water.