JPH03140968A - Monodisperse polymer colored particle and production thereof - Google Patents

Abstract

PURPOSE:To obtain the material which has excellent fluidity and electrostatic charge characteristics and is adequate for toner particles by dispersing and incorporating an oil soluble dye into the material and respectively specifying the ranges of the sphericity and particle size distribution thereof. CONSTITUTION:The oil soluble dye is dispersed and fixed into a polymer in such a manner that the sphericity is >=0.9 and the diameter based on volume satisfies the range of 50% particle D50 to 8mum and the particle difference between 25% particle D25 of the diameter based on volume and 75% particle D70 of the diameter based on volume satisfies a 0 to 1.5mum range. Monomers, the oil soluble dye, dispersion stabilizer and oily polymn. initiator are dissolved in a water-miscible org. solvent, etc., to polymerize and form prepolymer particles and to lower the solubility of the monomers and the oil soluble dye. The oil soluble dye, the monomers and the polymn. initiator are absorbed into the prepolymer particles to complete the polym. The monodisperse polymer colored particles which have the excellent fluidity and electrostatic charge stability and are adequate as the toner, etc., are obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to monodisperse polymer colored particles and a method for producing the same. The present invention relates to monodisperse polymer colored particles having excellent dispersibility in a resin, and also relates to a simple method for producing the colored particles.

(Prior Art) Generally, colored particles having a particle size of several μm to several tens of μm are expected to be used in electrophotographic toners, cosmetics, carriers for immunodiagnostic agents, and the like. In order to utilize colored particles for such purposes, their particle size distribution, sphericity, dispersibility and chargeability of colored pigments must be strictly controlled.

Conventionally, emulsion polymerization, suspension polymerization, and dispersion polymerization are known as methods for producing such colored particles, and among these methods, it is known that particles of lILm or more can be obtained by dispersion polymerization and suspension polymerization. ing. Furthermore, various methods have been proposed for coloring particles, which are often found in methods of manufacturing toners and the like.

For example, a method in which a pigment such as carbon black is preliminarily dispersed in a monodisperse polymerization prescription solution, and after the polymerization is completed, the pigment is filtered and dried to obtain colored particles of uniform particle size.

A method in which colored particles are obtained by surface-treating particles synthesized by dispersion polymerization in an organic solvent containing an oil-based dye.

Another method is to chemically treat the surface of dispersed polymerized particles in advance to obtain colored particles with excellent chargeability.

There is a method of obtaining colored particles by coating the surface of particles synthesized by dispersion polymerization with a pigment and a charge control agent (Japanese Patent Laid-Open No. 61-27
3552, JP 61-273553, JP 61-228458, JP 61-2380
No. 68, JP-A-61-18966. ) (Problem to be Solved by the Invention) However, with the method of adding a coloring pigment in advance to dispersion polymerization and incorporating the colorant into the polymer, dispersion into the resin is not easy and its dispersibility cannot be easily controlled. There are no defects.

Various methods for adding colored pigments to the surface of dispersed polymer particles require reliable processing to impart functionality.
There is a problem that the processing process is complicated.

Since the coloring dye of conventional monodisperse colored particles is not incorporated into the particles, it is difficult to obtain constant charging characteristics.

An object of the present invention is to provide colored monodisperse polymer particles of uniform particle size and high sphericity, which can be suitably used as toners and the like.

Another object of the present invention is to provide monopolymer colored particles with excellent dye dispersibility within the particle size.

A further object of the present invention is to provide a simple method for forming the monodisperse polymer colored particles.

(Means for Solving the Problems) According to the present invention, an oil-soluble dye is dispersed and contained inside,
Particles with sphericity of 0.9 or more and 50% of the volume standard diameter [
) go satisfies the range of 1 to 8#Lm, and 25% particles Do11 with 1 volume standard diameter and 75% particles D with volume standard diameter
Monodisperse polymer colored particles are provided, characterized in that the difference in particle size from No. 8 satisfies the range of 0 to 1.5 μm.

According to the present invention, the monomer, oil-soluble dye, A dispersion stabilizer and an oil-based polymerization initiator are dissolved in the solvent, and prepolymer particles are polymerized while incorporating a part of the oil-soluble dye, and the water concentration of the dispersion is increased or the water miscibility is increased. The oil-soluble dye, monomer, and monomer are incorporated into the prepolymer particles by employing measures to reduce the solubility of the monomer and the oil-soluble dye, such as reducing the concentration of the organic solvent or changing the temperature of the dispersion. Provided is a method for producing colored monodisperse polymer particles, characterized in that the polymerization is completed by absorbing a polymer and a polymerization initiator.

(Function) In the production method of the present invention, a dispersion medium mainly consisting of a water-miscible organic solvent that dissolves the monomer but does not dissolve the polymer, and also dissolves the oil-soluble dye, By using a monomer and an oil-based colorant dispersion medium that can reduce the solubility of oil-soluble dyes.

When monomers and oil-soluble dyes are added to such a dispersion medium, the monomers and oil-soluble dyes are easily dispersed in the dispersion medium by simple stirring or the like. Stirring in this case means a simple and hassle-free process, and the conventional dispersion process of applying heat and stirring strongly is not required for dispersing the colored dye.

Next, a polymerization initiator and a dispersion stabilizer are added to prepolymerize a portion of the monomer, and prepolymer particles in the form of seed polymer particles incorporating a portion of the oil-soluble dye are dispersed in the dispersion medium. .

The polymerization rate of the prepolymer particles is desirably 1% or more, particularly 10% or more; if it is less than this range, sufficient seed particles cannot be obtained. Furthermore, since the prepolymer particles exist in a dispersion medium in which monomers can be dissolved, their particle size is a swelling size.

In the presence of such prepolymer particles, if a method is adopted to reduce the solubility of the monomer and oil-soluble dye in the dispersion medium, the monomer and oil-soluble dye will be absorbed by the prepolymer particles, forming colored particles. is generated. If the dispersion medium is an organic solvent, the solubility of the monomer and oil-soluble dye can be decreased by increasing the concentration of water. If the dispersion medium is a water mixture, this can be done by further adding water. Further examples include means for changing the temperature of the dispersion medium and means for lowering solubility by adding an electrolyte such as sodium chloride into the dispersion medium, and these means can be used in combination.

As the solubility of the oil-soluble dye in the dispersion medium decreases, the colored dye is incorporated into the prepolymer particles along with the monomer.

Then, polymerization is completed while the oil-soluble dye is taken into the particles, and the oil-soluble dye is dispersed and fixed within the polymer. The monodisperse polymer particles manufactured in this way have a sphericity of 0 or 0.
．． 5 or more, and 50% particle D5゜ of volume standard diameter satisfies the range of 1 to 8ILm, and 25% particle D□ of volume standard diameter - 75% particle D7I of volume standard diameter
.

The particle size difference between the two can be within the range of 0 to 1.5 μm. It is understood that this means that particles with high sphericity and a sharp particle size distribution can be obtained. Also,
Such colored particles have good charging characteristics because the coloring dye has a good dispersion degree within the particles, and since the dye is fixed in the resin, they are not easily separated.

Therefore, the manufactured monodisperse polymer colored particles can be suitably used as a toner for electrophotography.

For example, when monodisperse polymer colored particles are used in a toner,
Since the particle size distribution of the particles is sharp, there is no difference in the accumulation of charged charges, and the generation of toner with a low charge amount is eliminated. Further, such sharpening of particles improves fluidity and charging stability, and improves reproduction of character images without causing image fogging. Furthermore, since the oil-soluble dye is polymerized while being incorporated into the particles, the colored dye is inside the resin and does not have much effect on the surface chargeability, and the above-mentioned uniformity of particle size makes the accumulation property uniform. In combination, constant charging characteristics can be obtained.

(Preferred Embodiment of the Invention) Uniformity) 1. Any oil-soluble dye can be used as long as it dissolves in the dispersion medium described below and its solubility is reduced by the above-mentioned means. The initial solubility of the oil-soluble dye in the dispersion medium is desirably 0°O1g/100g or more, especially 1g/100g or more, and if the solubility is below this range, the oil-soluble dye cannot be completely dissolved in the dispersion medium. For example, if the organic solvent mentioned below is methanol, the solubility of the oil-soluble dye in methanol at 20°C is:
Although it varies depending on the monomer used, 0.01g/1
00g or more, especially 1 g/100g or more.

Note that the initial solubility here does not mean the solubility in a pure water-miscible organic solvent, but the oil-solubility in a state in which the monomers and water-miscible organic solvents described below, and in some cases water, are mixed. Refers to the solubility of the dye.

Regarding the relationship between the oil-soluble dye and the monomer, it is desirable that the oil-soluble dye dissolves well in the monomer.

For example, if the monomer described below is an aromatic atom, it is desirable that the solubility of the oil-soluble dye therein is 0.1 or more, particularly 1 or more. In such cases, if the oil-soluble dye is not very soluble in the water-miscible organic solvent in the dispersion medium, the oil-soluble dye will be sufficiently dispersed by the monomer in the initial dispersion medium. As the polymerization progresses, the monomer decreases and loses solubility, and the dye migrates to the polymer particles within the same phase. Therefore, it is desirable that the solubility of the oil-soluble dye in the monomer is higher than the solubility in the water-miscible organic solvent.

1 Specific examples of oil-soluble dyes include black dye Black FS-3special A (Black F
S-Special A), Black S, Black #10:I
, black #107. Black #215, Black #
141 (both manufactured by Chuo Gosei Kagaku, trade name),
0PLAS (oblas) bluff') IIZ, 0
PLAS Black') #836.0 PLAS Black #838 (All manufactured by Orient Chemical Industries.

Product name) Red dye MACROLEx Let 5B, 1I
ACR〇-LEX Red Violet R (both manufactured by Bayer ■, product name), Sumiplast Red^S, Sumiplast Red 2. Sumiplast Red HLG-Z (
Both manufactured by Jumin Chemical Industry ■, product name), 0PLAS Red RR, 0PLAS Red $330
(All manufactured by Orient Chemical Industry ■, product name), Red 6
B, Red TR-71 (both manufactured by Chuo Gosei Kagaku ■, trade name) 2 Orange dye 11 AcROLEX (Macrolex) t Shil: /
C3G.

11AcROLEX Orange R (all manufactured by Bayer,
Product name), Orange S, Orange R, Orange 9826
8 (both manufactured by Chuo Gosei Kagaku ■, product name), 0PLA
S (Oblas) Orange PS, 0PLAS Orange R
R (both manufactured by Orient Chemical Industry ■, product name), S
ul*1-plast (Samiplast) Orange H
RP (manufactured by Sumima Kagaku Kogyo ■, product name) Yellow Dye Store ^CROLEX (Macrolex) Yellow 6G.

11AcROLEX-1' Engineering a-R (both Bayer) LtHm, trade name), Yellow D, Yellow GE, Yellow #189 (all manufactured by Chuo Gosei Kagaku, trade name),
Sumiplist Yellow GC
, Sumi-plug Yellow R (manufactured by Sumitomo Chemical ■, product name), (0PLAS Yellow 3G, 0PLAS Yellow #130
(All manufactured by Orient Chemical Industry ■, product name) Purple dye 1^ CROLEX Violet 3
R.

IIAcROLEX Violet B (manufactured by Bayer, trade name), Violet MVB (manufactured by Chuo Gosei Kagaku, trade name), Su 1plast (
Samiblast) Violet RR, 5usiplast
Violet B (manufactured by Sumima Kagaku Kogyo ■, product name), 0
PLAS Violet #370, 0PLAS Violet @732 (both manufactured by Orient Chemical Industry ■, product name) Blue dye MACROLEX (Ma') *Ly t')
) Bu JL/-Ft, (manufactured by Bayer ■, trade name), Blue aO, Blue #8B.

(all manufactured by Chuo Gosei Kagaku, product name), Sumipl
ast (Samiplas) Blue OR, Sumiplas
t Blue GP, Sumiplast Blue S (all manufactured by Sumitomo Chemical, trade names), 0PLAS Blue I
I N, 0 PLAS Blue $630 (All manufactured by Orient Chemical Industry ■, brand name) Green dye eel^CROLEX Green 5B.

MACROLEX Green G (manufactured by Bayer, product name), Green #550. Green #201 (both manufactured by Chuo Gosei Kagaku ■, product name), Su+eipal
st (Samiplast) Clean G (Sumitomo Chemical ■
(product name).

0PLAS Green #502, 0P
LAS Green #503. (manufactured by Orient Chemical Industry,
Product name) Brown dye Brown PB, Brown SG, (manufactured by Chuo Gosei Chemical Co., Ltd.)
Product name), 0PLAS Brown #43
Examples include 0°0 PLAS Brown #431 (manufactured by Orient Chemical Industry Co., Ltd., trade name).

The monomer used in the present invention is an ethylenically unsaturated monomer having radical polymerizability, and suitable examples thereof include monovinyl aromatic monomer, acrylic monomer, and vinyl ester monomer. These include vinyl ether monomers, diolefin monomers, monoolefin monomers, halogenated olefin monomers, poly(5) vinyl monomers, and the like.

The monovinyl aromatic monomer has the formula (wherein R1 is a hydrogen atom, a lower alkyl group or a halogen atom, and R2 is a hydrogen atom, a lower alkyl group,
monovinyl aromatic hydrocarbons such as styrene, α-methylstyrene, vinyltoluene, α-chlorostyrene,
O-, m-, p-chlorostyrene, P-ethylstyrene, sodium styrene sulfonate, and divinylbenzene may be used alone or in combination of two or more, and other monomers mentioned above include the following: are mentioned respectively.

6 CH2=C-Go-0-R4...(2) (in the formula, R3
is a hydrogen atom or a lower alkyl group, R4 is a hydrogen atom, a hydrocarbon group of up to 12 carbon atoms, a hydroxyalkyl group, a vinyl ester group, or an aminoalkyl group), such as acrylic acid, methacrylic acid, Methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, β-hydroxyethyl acrylate, γ -Butyl hydroxylate, δ-hydroxybutyl acrylate, β-hydroxyethyl methacrylate, γ-aminopropyl acrylate, γ-N,N-diethylaminopropyl acrylate, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate Esther et al.

Vinyl esters of CH2=CH 0'''C-R5 〇 (wherein R5 is a hydrogen atom or a lower alkyl group), such as vinyl formate, vinyl acetate, vinyl propionate, etc.

Vinyl ethers of the formula % (wherein R6 is a monovalent hydrocarbon group having up to 12 carbon atoms), such as vinyl methyl ether, vinyl ethyl ether, vinyl-n-butyl ether, vinyl phenyl ether, vinyl cyclohexyl ether, etc.

Diolefins of the formula %, in which each R7+ Ra + Re is a hydrogen atom, a lower alkyl group or a halogen atom, in particular butadiene, isoprene, chlorobrene and the like.

Monoolefins of the formula % (in the formula, each of R3° and R11 is a hydrogen atom or a lower alcohol), particularly ethylene, propylene, isoprene, butene-1, pentene-1,4-methylpentene-1, etc.

Examples of the halogenated olefin monomer include vinyl chloride and vinylidene chloride, and examples of the polyvinyl monomer include divinylbenzene, diallyl phthalate, and triallyl cyanurate.

These monomers can be used alone or in combination of two or more. Preferred monomers are styrene, (meth)acrylate, styrene/(meth)acrylate, styrene/divinylbenzene.

Water-miscible organic solvents include methanol, ethanol,
Lower alcohols such as isopropanol; polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, diethylene glycol, and triethylene glycol; cellosolves such as methyl cellosolve and ethyl cellosolve; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran Examples include esters such as ethyl acetate, and among these, those that dissolve the monomer but do not dissolve the polymer are used in combination with the monomer. Organic solvents that have excellent monomer solubility, can be mixed with water in any ratio, and are therefore particularly useful for the purposes of the present invention are lower alcohols such as ethanol.

This water-miscible organic solvent can be used alone or
It can also be used in the form of a mixture with water. In the latter case, it is desirable to contain as much water as possible without reducing the solubility of the monomer, and the mixing ratio is determined by the monomer and organic solvent used. When a lower alcohol is used as the organic solvent, the organic solvent and water can be used in a volume ratio of 10:1 to 3:5, particularly 4:3 to 3:4.

As the dispersion stabilizer for improving the dispersibility of the seed polymer particles in the solvent and dispersion medium, polyvinyl alcohol, methyl cellulose, ethyl cellulose, which are known per se, can be used.
Polymer dispersion stabilizers such as polyacrylic acid, polyacrylimide, polyethylene oxide, poly(hydroxystearate-g-methyl methacrylate-CO-methacrylic acid) copolymers, nonionic surfactants, and anionic interfaces. Active agents, cationic surfactants, amphoteric surfactants, etc. are used.

Among these, polymeric dispersion stabilizers such as polyvinyl alcohol are preferred and give good results when combined with an organic solvent-water mixture.

Any oil-soluble polymerization initiator can be used as the Otada JJL agent polymerization initiator. For example, as a radical polymerization initiator,
Can be used with monomers such as azo compounds such as azobisisobutyronitrile, peroxides such as cumene hydroperoxide, t-butyl hydroperoxide, dicumyl peroxide, di-t-butyl peroxide, benzoyl peroxide, and lauroyl peroxide. A soluble one is used. Furthermore, in the case of polymerization using ultraviolet rays, oil-soluble photopolymerization initiators among known photopolymerization initiators can be used.

According to the basic invention, a monomer is first dissolved in a water-miscible organic solvent or a mixture thereof with water. The amount of monomer dissolved is
Although it varies considerably depending on the type and composition of the solvent and monomer, it is generally 0. A range of 1 to 50% by weight, particularly 1 to 20% by weight is preferred.

An oil-soluble dye, a dispersion stabilizer, and a polymerization initiator are added to this solution. The amount of oil-soluble dye added also varies depending on the desired degree of coloring density.

Generally 1=1 to 1:109 especially 1:10 to l:lO6
It is desirable to have it present in a weight ratio of . - On the other hand, the concentration of prepolymer particles in the dispersion is generally from 0.0001 to 50% by weight, in particular from 0.0001 to 50% by weight. It is preferable to use it in a range of 20% by weight. Further, the dispersion stabilizer is preferably used in an amount of 0.1 to 30% by weight, particularly 1 to 10% by weight, based on the prepolymer particles, while the polymerization initiator is used in an amount of 0.001 to 10% by weight, based on the monomer charged. %, especially 0.01 to 0.5% by weight.

When the polymerization rate reaches about 20% in this dispersion, the solubility of the monomers in the system is reduced by adding water, evaporating the solvent, or lowering the temperature. According to the present invention, by adding water to the polymerization system or further lowering its temperature, substantially all of the charged monomers and dyes can be precipitated and absorbed into the prepolymer particles. Generally, 50% or more polymerization of the charged monomer, especially 70%
It is desirable to have at least 3% by weight absorbed into the seed polymer particles. A remarkable feature of the present invention is that this treatment is carried out within an extremely short period of time, and the polymerization initiator is also absorbed at the same time as the monomer is absorbed.

The monomers absorbed into the polymer particles are then polymerized.

The polymerization is generally carried out at a temperature of -30°C to 90°C, especially 30°C to 80°C, in an inert atmosphere such as nitrogen. The polymerization time is the one that completes the polymerization of the absorbed monomer,
Generally, 0.1 to 30 hours is suitable. The method of the present invention may be carried out in only one stage, or may be carried out in multiple stages until the grains are grown to a predetermined size. The resulting polymer is characterized by being highly monodisperse, generally with a particle size of 1 to 10 μm. The obtained polymer particles can be used in the form of a suspension for various purposes, or after being separated by filtration and washed with water if necessary, they can be used in the form of a powder for various purposes.

In addition, the obtained colored polymer particles have a sphericity that satisfies the above range and have a particle size of 50% of the volume-based diameter. can satisfy the range of 1 to 8 μm, and the difference in particle size between the particles 5 having a volume standard diameter of 25% and the particles ys having a volume standard diameter of 75% can satisfy a range of 0 to 1.5 μm. These colored particles have a sharper particle size distribution and higher sphericity than conventional particles.

Note that D 1s+ D 5o and D 7B represent particle diameters corresponding to 25%, 50%, and 75% of the total volume of the entire particle. Moreover, sphericity is as follows: In the formula, rL represents the major axis of the particle, and rS represents the minor axis of the particle. When monodisperse polymer colored particles with such characteristics are used in toner, the particle size distribution of the particles is sharp, so there is no difference in the accumulation of electrostatic charges, resulting in the generation of toner with a low charge amount. disappears. Further, such sharpening of particles improves fluidity and charging stability, and improves reproduction of character images without causing image fogging. Furthermore, since the colored dye is contained inside, it also has excellent charging characteristics.

(Effects of the Invention) According to the present invention, the monodisperse polymer colored particles contain an oil-soluble dye, have a sphericity of (1.9 or more, and have a volume-based diameter of 5
0% particle so satisfies the range of 1 to agm, and 25% of the volume standard diameter Particle B and 75% of the volume standard diameter
As long as the difference in particle size from particle size 5 satisfies the range of 0 to 1.5 #Lm, a material suitable for toner particles with excellent fluidity and charging characteristics can be provided.

Furthermore, according to the present invention, a water-miscible organic solvent that dissolves the monomer or does not dissolve the polymer is used as the solvent, and the monomer, oil-soluble dye, dispersion stabilizer, and oil-based polymerization initiator are contained in the solvent. The oil-soluble dye, monomer, and polymerization initiator are absorbed into the prepolymer particles by dissolving or dispersing them in the prepolymer particles to form prepolymer particles, and employing means for reducing the dissolution of the colored dye and monomer. Since the polymerization is completed in a single step, there is no need for a complicated dye dispersion process, and excellent colored particles can be obtained within the reaction system.Moreover, the obtained colored particles have high sphericity and a good particle size distribution. and has excellent charging characteristics.

The present invention will be explained below using Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 2.5 g of methacrylic acid-methyl acrylate copolymer was dissolved in a mixed medium of 200 g of ethanol and 40 g of water, and 60 g of styrene and 2.5 g of azobisisobutyronitrile were dissolved therein.
g and Sug+1plus manufactured by Sumitomo Chemical Co., Ltd.
Add 1.8 g of Burdrex HBL (the solubility of this dye is shown in Table 1). After confirming that all of these reagents were completely dissolved, they were placed in a separable flask (No. 11) under a nitrogen atmosphere.

Polymerization was carried out at 70° C. for 200 minutes while stirring at a speed of 40 rpm. Thereafter, water was added dropwise into the separable flask at a rate of 0.1 sl/in for 1000 minutes using a microfeeder manufactured by Furue Science. When this emulsion was observed under an optical microscope, it was found that strongly red colored particles with uniform particle sizes of approximately Tp, m were formed. This emulsion was filtered, washed and dried to obtain a red powder. The particle size distribution of this powder measured by a Coulter counter is shown in FIG. Further, the sphericity of the particles was 0.98.

Furthermore, 0.01% by weight of hydrophobic silica was mixed with this powder to form a toner composition, and a developer was adjusted so that the spherical ferrite particles with an average particle size of 80 μm and the toner concentration were 3.5%. When a copied image was obtained using a modified electrophotographic copying machine DC-1205 (manufactured by Sanda Kogyo Co., Ltd., trade name), a clear red image without fogging was obtained.

Example 2 2.5 g of polymethacrylic acid was dissolved in a mixed medium of 220 g of ethanol and 20 g of water, and 60 g of styrene, 2.5 g of azobisisobutyronitrile, and Sumiplast Blue S manufactured by Sumitomo Chemical Co., Ltd. The solubility of the dye is shown in Table 1.) Add 1.8 g. Confirm that all of these reagents are completely dissolved, and place them in a separable flask for 40 minutes under a nitrogen atmosphere.
Polymerization was carried out at 75° C. for 200 minutes while stirring at a speed of rpm. Thereafter, water was added dropwise into the separable flask at a rate of 0.1 l/in for 1000 minutes using a microfeeder manufactured by Furue Science. When this emulsion was observed with an optical microscope, it was found that strongly blue-colored particles with a uniform particle size of about 4 pm were formed. The emulsion was filtered, washed and dried to obtain a blue powder. The particle size distribution of this powder measured by a Coulter counter is shown in FIG. Further, the sphericity of the particles was 0.97.

Furthermore, when a copy image was obtained in the same manner as in Example 1, a blue image was obtained that was clear, free from fog, and had excellent resolution.

Example 3 2.5 g of acrylic acid-methyl acrylate copolymer was dissolved in a mixed medium of 230 g of methanol and 10 g of water, and to this was added 60 g of methyl methacrylate, 2.5 g of azobisisobutyronitrile, and 2.5 g of acrylic acid-methyl acrylate copolymer. ^CROLEX Y
Add 1.8 g of yellow 6G (the solubility of this dye is shown in Table 1). After confirming that all of these reagents were completely dissolved, they were placed in a separable flask (No. 11) and polymerized at 60° C. for 200 minutes while stirring at a speed of 40 rpm under nitrogen flow. Thereafter, water was added dropwise into the separable flask at a rate of 0.1 g+I/sin for 1000 minutes using a microfeeder manufactured by Furue Science. When this emulsion was observed under an optical microscope, it was found that strongly yellow colored particles with uniform particle diameters of about 5 μm were formed. The emulsion was filtered, washed and dried to obtain a yellow powder. The particle size distribution of this powder measured using a Coulter counter is shown in FIG. Further, the sphericity of the particles was 0.98.

Furthermore, in the same manner as in Example 1, an OHP diversion material photographic image was formed. The resulting image was clear with no fog and had excellent translucency.

Comparative Example 2.5 g of methacrylic acid-methyl acrylate copolymer was dissolved in a mixed medium of 200 g of ethanol and 40 g of water, and 80 g of styrene and 2.5 g of azobisisobutyronitrile were dissolved therein.
g and 5pilon Or manufactured by Hodogaya Chemical Industry Co., Ltd.
ange 2RH (the solubility of this dye is shown in Table 1).

) 1.8 g was added. All these reagents were completely dissolved before polymerization. This was placed in a separable flask (No. 11) and polymerized at 70° C. for 200 minutes under a nitrogen stream while stirring at a speed of 40 rpm. After that, add water to the separable flask using a microfeeder made by Furuju Science Co., Ltd., and add 0.1 ml/+ein of water to the separable flask.
The mixture was added dropwise for 1000 minutes at a rate of . When this emulsion was observed using an optical microscope, it was found that some particles were slightly colored orange, but most of the added dye was precipitated as dye crystals.

1 From the Examples and Comparative Examples, it is clear that when a polymerization reaction is carried out according to the method of the present invention using an oil-soluble dye that is compatible with both a water-miscible organic solvent and a monomer, the dye has high coloring property and is monodisperse. It can be seen that spherical particles are obtained.

Furthermore, since the coloring property and charging property are also good, it can be seen that it can be effectively used as a toner.

[Brief explanation of the drawing]

Figures 1, 2 and 3 are diagrams representing particle size distributions measured by a Coulter counter.

Claims (8)

[Claims] (1) Contains oil-soluble dye dispersed inside and has 0 sphericity
．． 9 or more and 50% particle diameter of volume standard diameter D_5_0
satisfies the range of 1 to 8 μm, and the volume standard diameter is 2
5% particle size D_2_5 and 75% particle size D_ of volume standard diameter
Monodisperse polymer colored particles characterized in that the difference in particle size from 7_5 satisfies the range of 0 to 1.5 μm. (2) The oil-soluble dye has a solubility in the monomer constituting the monodispersed polymer particles of 0.1 g/100 g at 20°C.
The monodispersed polymer colored particles according to claim 1, which have the above properties. (3) A water-miscible organic solvent that dissolves the monomer or does not dissolve the polymer, or a mixture of the water-miscible organic solvent and water, is used as the solvent, and the monomer, oil-soluble dye, dispersion stabilizer and An oil-based polymerization initiator is dissolved in the solvent to polymerize and form prepolymer particles while incorporating some of the oil-soluble dye, and the water concentration of the dispersion is increased or a water-miscible organic solvent is added. Complete the polymerization by absorbing the oil-soluble dye, monomer, and polymerization initiator into the prepolymer particles by reducing the concentration or reducing the solubility of at least one monomer and the oil-soluble dye. A method for producing colored monodisperse polymer particles, the method comprising: (4) The method for producing colored monodisperse polymer particles according to claim 3, wherein some or all of the monomers are aromatic vinyl monomers. (5) The production of monodisperse polymer colored particles according to claim 4, wherein the dye is selected so that its solubility in a water-miscible solvent is lower than its solubility in the aromatic vinyl monomer. Method. (6) The manufacturing method according to claim 3 or 4, wherein the monomer is a styrene monomer or a styrene and (meth)acrylate comonomer. (7) The manufacturing method according to claim 3 or 5, wherein the dye has a solubility in methanol at 20°C of 0.01 g/100 g or more at 20°C. (8) The dispersion stabilizer is polyacrylic acid, polymethacrylic acid, polyethylene oxide, polyvinylpyridine,
4. The method of claim 3, wherein the polyvinylpyrrolidone is selected from the group consisting of polyvinylpyrrolidone and copolymers containing these, and copolymers of maleic anhydride and maleic acid.