JP3215985B2 - Colored polymer particles and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to colored polymer particles by an emulsion polymerization method, a method for producing the same, and uses of the colored polymer particles.

[0002]

2. Description of the Prior Art Disadvantages of the prior art There are emulsion polymerization, suspension polymerization, dispersion polymerization and the like, which are generally used as methods for producing polymer particles. Each of the polymer particles produced by these polymerization methods and the polymerization method has its own characteristics. For example, polymer particles produced by emulsion polymerization generally have an average particle size of 1 μm or less and a relatively simple particle size distribution. Although it is dispersed, it is characterized by being hard to contain a coloring agent, and as a rescue measure often used, a method of coloring with a dye is used. In the suspension polymerization, a colorant is easily contained, but the average particle diameter of the generated particles is usually about several μm or more, and the particle size distribution is very broad.
Furthermore, in dispersion polymerization, the average particle size of the produced particles can be selected relatively arbitrarily by selecting the solvent used, and it is known that the particle size distribution is also monodisperse. For this reason, it is the present situation that a major problem remains in post-processing.

[0003] Against this background, the production of polymer particles containing a colorant has conventionally been mainly carried out by suspension polymerization. However, in recent years, colored polymer particles having a uniform particle size have been demanded in various fields.

[0004] In order to cope with such an object, various studies have been made on selecting an emulsion polymerization system to synthesize colorant-containing polymer particles. For example, JP-A-1-93748, 1-9
No. 3749 discloses a method of mechanically fixing a pigment to the resulting emulsion polymerized particles.
Nos. 68, 2-93657 and 2-93659 employ a technique of adding a pigment (colorant) to polymerized particles to aggregate and fix the particles. However, in all of these methods, the pigment is exposed on the surface of the resulting polymer particles, which causes problems in storage stability and the like.When used as a toner for developing an electrostatic image, triboelectric charging is required. There are problems such as adverse effects on characteristics and the like.

Further, goat red blood cells or white resin latex has conventionally been used as a carrier for immunological analysis. However, white resin latex is colorless and thus it is difficult to make an actual determination. Having.

[0006]

(1) To provide (monodispersed) colored polymer particles having a uniform particle size distribution.

(2) To provide colored polymer particles having excellent storage stability.

(3) To provide an electrostatic image developing toner having excellent storage stability and triboelectric charging characteristics.

(4) To provide an immunoassay carrier which is excellent in visual judgment, has high reactivity and is very easy to judge.

[0010]

The object of the present invention is to contain at least an ethylenically unsaturated monomer serving as a base of polymer particles and a water-soluble radical polymerization initiator in an aqueous phase, and heating the reactive solution. Then, the polymerization reaction is started. As the reaction time changes, the polymerization conversion of the monomer to the polymer increases,
This polymerization conversion was prepared separately between 20 and 85%.
Add an aqueous dispersion of a colorant containing a surfactant ,
The concentration of the surfactant in the aqueous phase is less than the critical micelle concentration.
By polymerizing under the above conditions, the colorant is incorporated in the polymer particles, and the intended colored polymer particles can be obtained.

The colored polymer particles thus obtained are
Since it has a very narrow particle size distribution, has excellent storage stability, and is not contaminated by contaminants, it can be effectively used as a carrier for immunological diagnosis. In particular, it is advantageous in that it is colored, so that it is easy to make a visual judgment, and the particle size is very small, so that the reactivity is high.

When used as a toner for developing an electrostatic image, the colored polymer particles obtained as described above can be used, for example, by the method described in JP-A-60-220358. After coagulation, it is dried and, if necessary, crushed to obtain a desired particle size. The toner particles thus obtained are excellent in storage stability and triboelectrification and are very useful.

A feature of the present invention resides in that the colorant is incorporated when the polymerization conversion ratio is a predetermined value. When the polymerization conversion ratio is within this range, the latex having a viscous paste is used. It is considered that the coloring agent is incorporated into the soft viscous tissue because of the shape.

The present invention is characterized in that the polymerization conversion is a predetermined value , and the concentration of the surfactant in the aqueous phase is critical micelle.
When the concentration is less than the concentration , the colorant is built-in.When the latex has a polymerization conversion rate in this range, since the surface is in the form of a viscous paste, the colorant is It is considered to take in.

As the polymerizable monomer used for synthesizing the colored polymer particles of the present invention, known ones can be used. In particular, radically polymerizable ones are preferable, and are required as the particle diameter of the completed synthesis. To satisfy thermal and static characteristics
Species or a combination of two or more can be used. Specific examples of such a thing include a vinyl aromatic monomer, an acrylic monomer, a vinyl ester monomer, a vinyl ether monomer, an olefin monomer, etc. Referred to as ethylenically unsaturated monomers).

As the vinyl aromatic monomer, styrene,
o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, pn-butylstyrene,
pt-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, 3,
Examples include styrene-based monomers such as 4-dichlorostyrene and derivatives thereof.

Acrylic monomers include acrylic acid,
Methacrylic acid, methyl acrylate, ethyl acrylate,
Butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, β-hydroxyethyl acrylate, γ -Propyl aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and the like.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, vinyl benzoate and the like.

Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like.

As the olefin-based monomer, ethylene,
Propylene, isobutylene, 1-butene, 1-pentene, 4-
Monoolefinic monomers such as methyl-1-pentene and diolefinic monomers such as butadiene, isoprene and chloroprene are exemplified.

Further, a crosslinking monomer may be added in order to improve the polymer properties. As a crosslinkable monomer,
Examples thereof include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.

As the coloring agent used in the present invention, known ones can be used. If necessary, a surface treatment of these coloring agents to improve their dispersibility can be used. Good. In addition, as the colorant when used as a toner, any colorant can be used as long as it gives a color required for the developer to the developer. As these colorants, inorganic and organic pigments are preferably used, and particularly, organic pigments are preferably used.

More specifically, as the black color, commercially available carbon black (hereinafter referred to as CB.
) And C.I. grafted with a polymerizable monomer or the like. B. Surface-treated with a surface treating agent such as a silane coupling agent or an aluminum coupling agent. B. And pigments for magenta or red include C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I.
I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I. I. Pigment Red 48, C.I. I. Pigment Red 53, C.I. I. Pigment Red 57, C.I.
I. Pigment red 122, C.I. I. Pigment Red 1
23, C.I. I. Pigment Red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I.
Pigment red 166, C.I. I. Pigment Red 177,
C. I. Pigment red 178, C.I. I. Pigment Red 222, and the like.

Examples of pigments for orange or yellow include C.I. I. Pigment Orange 31, C.I. I. Pigment Orange 43, C.I. I. Pigment Yellow 12, C.I.
I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I.
I. Pigment Yellow 94, C.I. I. Pigment Yellow 138 and the like.

Green or cyan pigments include C.I.
I. Pigment Blue 15, C.I. I. Pigment Blue 1
5: 2, C.I. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I.
Pigment Green 7 and the like.

These colorants can be used alone or in combination of two or more according to the desired color tone. The amount of the colorant added is 2 to 20 parts, preferably 3 parts, based on the polymer. ~ 15 parts are added.

As the polymerization initiator used in the polymerization, conventionally known ones can be used. For example, persulfates such as potassium persulfate (potassium peroxodisulfate) and ammonium persulfate and 2,2'-azobis (2 Water-soluble azo initiators such as -amidinopropane) dihydrochloride and water-soluble peroxides such as hydrogen peroxide can be used, but are not limited thereto. By using a water-soluble initiator and a reducing agent in combination, a redox-based initiator can be used. By using a redox-based initiator, it is possible to increase the polymerization activity, lower the polymerization temperature, and shorten the polymerization time.

Furthermore, it is possible to use two or more initiators simultaneously for adjusting the molecular weight and controlling the properties of the polymer.

Further, for the purpose of adjusting the molecular weight, a commonly used chain transfer agent can be used, but octyl mercaptan and octyl mercaptan are particularly suitable.
Mercaptans such as dodecyl mercaptan are most used, but are not particularly limited thereto, and any substance having a large chain transfer constant can be used.

The actual polymerization is preferably a soap-free emulsion polymerization. The reason is that there is no surfactant at the resulting particle interface, so it is easy to incorporate the colorant,
In addition, the surface of the resulting particles is excellent in storability, and is particularly useful when used as a toner for developing an electrostatic image. In the aqueous dispersion of the colorant, a surfactant or a dispersion stabilizer (hereinafter, collectively referred to as a dispersant) can be used to perform fine particle dispersion. When the colorant is dispersed therein, the concentration of the colorant is stopped so that the colorant can be easily dispersed. It is below the concentration at which no new particles are formed in the aqueous phase. Specifically, when the dispersant is a surfactant, when the colorant is dispersed, the surfactant concentration is equal to or higher than the critical micelle concentration (CMC), and is added to the finally polymerized system. Means that the concentration is less than the critical micelle concentration.

This is because, when the surfactant desorbed from the surface of the colorant particles is CMC or more, micelles are formed by the surfactant alone, and unreacted monomers in the polymerization process are formed in the micelle. This is because polymer particles containing no colorant are produced because emulsion polymerization occurs and new particles are produced.

The dispersion of the colorant in the aqueous phase can be carried out by a conventional dispersion technique. That is, it is possible to use dispersion by a pressure type disperser, dispersion by a rotor or stator type disperser, dispersion by an ultrasonic homogenizer, dispersion by shearing force by high-speed rotation, and the like.

As the dispersant, generally known dispersants can be used. For example, a water-soluble polymer; a poorly soluble fine powdered inorganic compound, and a sulfonate (such as sodium dodecylbenzenesulfonate) often used as a surfactant; a sulfate (such as sodium tetradecyl sulfate) A fatty acid salt (such as sodium oleate), but is not limited thereto.

In the case where a water-soluble polymerization initiator is contained in the colorant dispersion solution to be added, the polymerization of radicals which occurs when the colorant is added can be relaxed. Compared to the case where it is not contained,
The particle size distribution of the resulting colored polymer particles becomes sharper and excellent.

When the colored polymer particles of the present invention are used as a toner for developing an electrostatic image, components to be added as the toner (for example, a fixability improving agent, a charge control agent, etc.) are added as necessary. It is possible. These components can be introduced by adding a desired amount of each component to the polymerizable monomer. In addition, when finally used as a toner, various additives (commonly referred to as external additives) can be blended and mixed to improve fluidity and chargeability.

As the fixability improving agent, known ones can be used, and generally, polyolefin is often used. In particular, low molecular weight polyethylene, polypropylene and their oxidized or acid-modified ones can be used. As the charge control agent, it is also possible to use a known charge control agent. For example, as a positive charge agent, a nigrosine-based electron donating dye, a metal salt of naphthenic acid or a higher fatty acid, or an alkoxylated compound may be used. Amines, quaternary ammonium acids, alkyl amides, metal complexes, pigments, etc. can be used. For negative charging, electron accepting organic complexes, chlorinated paraffins, chlorinated polyesters, sulfonylamines of copper phthalocyanine And the like, but are not limited thereto. Furthermore, as an external additive when finally used,
For example, inorganic fine particles such as hydrophobic silica, titanium oxide, alumina, and sulfides, nitrides, and silicon carbide thereof;
Organic fine particles such as polyvinylidene fluoride, polystyrene, polymethyl methacrylate, and polyethylene; generally known fine particles such as fine powders of metal salts of fatty acids can be used according to the respective purposes.

As a carrier for an immunological diagnostic agent, it is necessary to immobilize an immunologically active substance, for example, an antigen, an antibody or a receptor on the particle surface. As these fixing methods, a physical adsorption method and a chemical fixing method are well known.

The former method is a method of physically adsorbing and immobilizing on a hydrophobic surface. For example, it is easy to use polymer particles using styrene and its derivatives, acrylates, methacrylates and the like. In addition, it can be immobilized in such a manner that an immunologically active site [for example, (Fab) '] is not adsorbed. Naturally, when IgG is used as an antibody, (Fab ′) ² or Fab ′ obtained by digesting an Fc fragment can be used. Further, in the case of chemical immobilization, for example, using a polymer particle of the present invention obtained by copolymerizing a polymerizable monomer having a functional group such as a carboxyl group, an amino group, and a thiol group, using a known bifunctional It is possible to react an immunologically active substance using a sex reagent and immobilize the substance by covalent bonding.

At this time, the polymerizable monomer having a functional group may be added as a copolymer monomer at the time of polymerization, and the monomer having the functional group may be added in an appropriate amount as necessary. Can be determined, for example, it is desirable to select from the range of 0.1 to 15%. As the antibody to be used, a polyclonal antibody and a monoclonal antibody can be appropriately selected. When used for an agglutination test or an agglutination inhibition test, a polyclonal antibody is preferable. When using a monoclonal antibody, it is desirable to use a mixture of several types of antibodies having different binding sites for the antigen.

[0040]

【Example】

(1) Preparation of Dispersion Solution of Pigment 0.20 g of sodium dodecylbenzenesulfonate (hard type) (manufactured by Tokyo Kasei Kogyo Co., Ltd.), which is a commercially available surfactant, was added to 1.78 g of the pigment, and further ions substituted with N ₂ gas were used. Mix 50 ml of the exchange, and use an ultrasonic dispersing device (ultrasonic homogenizer; US-150T [manufactured by Nippon Seiki Seisakusho]).
Dispersion was performed for minutes. Table 1 shows the particle size distribution of each dispersed pigment.
Shown in

The critical micelle concentration of the sodium dodecylbenzenesulfonate used was 1.63 × 10 ⁻³ [m
ol / l].

[0042]

[Table 1]

Note that the CV value is a value representing the degree of dispersion of the particle size distribution, and is a numerical value defined by the following equation. The smaller this value is, the sharper the particle size distribution is.

The particle size distribution was measured using a laser diffraction particle size analyzer SALD-1100 (manufactured by Shimadzu Corporation).

CV = σ ₅₀ / d ₅₀ d ₅₀ : 50% diameter of particle size distribution (volume basis) σ ₅₀ : standard deviation based on d ₅₀ (2) Examples and comparison on synthesis of colored polymer particles Example Example 1 Temperature sensor in a 500 ml round bottom separable flask
A polymerization reactor was prepared by attaching a nitrogen inlet tube, a stirrer (equipped with a disk turbine type stirring blade having a diameter of 50 mm) and a cooling tube.

This polymerization reactor was charged with 300 ml of ion-exchanged water substituted with N ₂ , 28 ml of a styrene monomer, and 5 ml of a butyl acrylate monomer, and heated to 70 ° C., whereupon potassium peroxodisulfate (common name: persulfate) as a polymerization initiator was added. 1.50 g of potassium) was completely dissolved and added to 50 ml of ion-exchanged water substituted with N ₂ to start a polymerization reaction.

When the polymerization addition rate of this polymerization reaction reached 30%, the black pigment dispersion solution (Pig-01) was added at an addition speed of 0.5 m.
It was added to the reaction system at 1 / min, and the polymerization reaction was further advanced to complete the reaction to obtain black colored polymer particles CLB-01. The polymerization addition rate at the end of the addition of the black pigment dispersion was 62%.

Example 2 In Example 1, the pigment dispersion to be added was changed to blue (Pig-02), and the addition of the pigment dispersion was started at a polymerization addition rate of 20%. Except for the above, a blue colored polymer particle CLC-01 was obtained in the same manner as in Example 1. Incidentally, the polymerization addition rate at the end of the addition of the blue pigment dispersion was 54%.

Example 3 In Example 1, the pigment dispersion to be added was changed to red (Pig-03), and the addition of the pigment dispersion was started at a polymerization addition rate of 55%. Except that in the same manner as in Example 1, red colored polymer particles CLM-01 were obtained. The polymerization addition rate at the end of the addition of the pigment dispersion was 83%.

Example 4 In Example 1, the pigment dispersion to be added was changed to yellow (Pig-04), and the addition of the pigment dispersion was started at a polymerization addition rate of 40%. Except that in the same manner as in Example 1, yellow colored polymer particles CLY-01 were obtained. The polymerization addition rate at the end of the addition of the pigment dispersion solution was 74%.

Example 5 A colorant dispersion in which 1.0 g of potassium persulfate as a water-soluble polymerization initiator was dissolved in a black pigment dispersion (Pig-01) was used, and this colorant dispersion was added. Except that the polymerization addition rate at the start was 35%, colored polymer particles CLB-11 were obtained in exactly the same manner as in Example 1. The polymerization addition rate at the end of the addition of the colorant dispersion was 79%.

Comparative Example (1) In Example 1, 0.20 g of sodium dodecylbenzenesulfonate as a surfactant was added to the N ₂ -substituted ion-exchanged water charged in the polymerization reactor, and a black color dispersion was obtained. The time to start adding the solution (Pig-01) is the polymerization addition rate of 33%
The polymerization proceeded to obtain colored polymer particles in exactly the same manner except that it was, but as the polymerization proceeded, the solution became grayish, and the colorant particles and the polymer particles were phase-separated. As a result, colored polymer particles could not be obtained. The reason for this phase separation is that the surfactant concentration in the reactor was higher than the CMC as described above, so that micelles were formed, and the polymerization reaction proceeded in the micelles. The particles obtained at this time are referred to as CLB-02.

Comparative Example (2) At the time of preparing the colorant dispersion solution (Pig-01), it was completely different from Pig-01 except that the addition amount of sodium dodecylbenzenesulfonate as a surfactant was 0.04 g. Except that the colorant dispersion solution (Pig-05) of (d ₅₀ = 0.11; CV = 0.09) obtained in the same manner was used and the addition start time of the colorant dispersion solution was 28%, Colored polymer particles were synthesized in exactly the same manner as in Example 1. However, phase separation of the colorant and the polymer particles occurred in the latter half of the polymerization reaction, and the solution became grayish, resulting in a colored polymer. No particles could be obtained. The cause of this phase separation can easily be inferred to be the same as in Comparative Example (1).
The particles obtained at this time are referred to as CLB-03.

Comparative Example (3) Colored polymer particles were prepared in exactly the same manner as in Example 1, except that the black colorant dispersion (Pig-01) was added at a polymerization addition rate of 15%. Although it was attempted to obtain polymer particles containing a coloring agent, it was possible to obtain polymer particles containing the coloring agent. As a result, a relatively small amount of relatively large particles which seemed to be agglomerated by polymer particles were also contained, and monodispersed uniform colored polymer particles could not be obtained. The particles obtained at this time are referred to as CLB-04.

Comparative Example (4) In Example 1, the addition of the black colorant dispersion (Pig-01) was started at a polymerization addition rate of 65%, and the polymerization addition rate at the completion of the addition was 89%. , Except that the colored polymer particles were obtained in exactly the same manner as in Example 1, except that the final solution was slightly gray and the polymer particles and the colorant were phase-separated. No colored polymer particles could be obtained. The particles obtained at this time are referred to as CLB-05.

Table 2 summarizes the results of Examples 1 to 5 and Comparative Examples (1) to (4).

[0057]

[Table 2]

(3) Examples and Comparative Examples Related to Toner for Electrostatic Electrodevelopment Example 6 The black colored polymer particles CLB-01 obtained in Example 1 are described in JP-A-60-220358. A non-spherical black toner having an average particle size of 5.3 μm after salting out by a method similar to that described above, and further subjected to a heat treatment to increase the bonding force of the individual colored polymer particles in the associated particles, and then drying. T-
B1 was obtained.

Examples 7 to 9 In the same manner as in Example 6, each of the colored polymer particles CLC-01; CLM-01;
5.5 μm, 4.8 μm and 5.2 μm cyan, magenta and yellow non-spherical toners T-C1, T-M1 and T-Y1 were obtained.

Comparative Example (5) A styrene / butyl acrylate (85/15 wt%) copolymer resin had the same content as the carbon black T-B1 toner used in the colorant dispersion (Pig-01). After mixing, a toner (T-BP1) having an average particle size of 5.5 μm was obtained by a kneading and pulverizing method.

To each of the toners obtained in Examples 6 to 9 and Comparative Example (5), 3.5 parts by weight of hydrophobic silica, 1.8 parts by weight of titanium oxide and 0.4 parts by weight of zinc stearate were attached as external additives. Mixing was performed to obtain an external additive-treated toner. 5.0 parts by weight of the toner treated with the external additive and 95.0 parts by weight of copper-zinc ferrite having an average particle diameter of 44 μm and surface-coated with a styrene / acrylic polymer were mixed to prepare respective developers.

Using these developers, an electrophotographic copying machine “Koni” equipped with a heat roller fixing device and a cleaning blade was used.
ca U-bix 3035 ”(made by Konica Corporation)
A 20,000 copy live-action test was performed and the following items were evaluated. Table 3 shows the evaluation results.

[0063]

[Table 3]

Evaluation Items Resolution of Copy Image The fine line reproducibility check chart was copied, and the output image was evaluated for resolution based on the number of identifiable fine lines per 1 mm.

Fogging of the background portion of the copied image Continuous copying is performed in an environment of a temperature of 20 ° C. and a relative humidity of 60%, and a reflection densitometer “Sakura Densitometer PDA-6” is used.
0 ”(manufactured by Konica Corporation), the reflection density of each color in the background portion was measured (measurement was performed at a fixed position 5 in the copy image).
The points were measured, and the arithmetic mean value of the five points was defined as the reflection density.
The number of copies when this value became 0.1 or more was regarded as the occurrence of fogging.

Degree of coloring of toner itself Each toner is adhered to an adhesive label in a single layer,
The degree of coloring of each color toner was evaluated by using the above-mentioned reflection densitometer for the toner layer. Regarding evaluation, in the case of black, the reflection density is good if the reflection density is 1.3 or more, slightly good if it is between 1.1 and 1.3, and the color toner is good if it is 1.1 or more and between 1.0 and 1.1. If any, it was slightly better.

Cleaning Characteristics Continuous copying was performed in an environment of a temperature of 20 ° C. and a relative humidity of 60%, and the image output at this time was evaluated by the number of copies at the time when cleaning failure occurred.

Image Density Continuous copying was performed under an environment of a temperature of 20 ° C. and a relative humidity of 60%, and the reflection density of a solid portion (original original density 1.3) was evaluated. In the case of black, the density was judged to be good if the density exceeded 1.2, and in the case of color, it was judged to be good if the density was 1.1 or more.

Fine toner content In continuous copying under an environment of a temperature of 20 ° C. and a relative humidity of 60%, a volume% of 2.0 μm or less in the toner at the start and a 2.0 μm or less in the toner at the completion of 20,000 copies. The evaluation was performed by volume%.

As is clear from the results shown in Table 3, the toner using the colored polymer particles of the present invention has a sharper particle size distribution as compared with the toner produced by the kneading and pulverizing method, and has excellent durability. It turns out to be something.

(4) Implementation and Comparative Example for Carrier for Immunological Diagnostics Colored polymer particles CL of the present invention synthesized in Example 5
B-11 was prepared as immunodiagnostic particles according to the following formulation.

For a cellulose dialysis bag with a molecular weight cut off of 1000
After the CLB-11 dispersion was added and the resulting solution was dialyzed for 24 hours with pure water, the solution was concentrated to a solid concentration of 5% using an ultrafiltration apparatus. To this, add a buffer and sodium chloride to add 0.
Resuspended in 1M PBS.

After adding an anti-α-fetoprotein antibody (IgG fraction) to this dispersion, physical adsorption was performed at 4 ° C. for 24 hours.

This was converted to a polymer solid content of 0.2% of 0.1 M
It was diluted with PBS (pH = 7.2) to obtain an immunodiagnostic reagent for AFP. Purified human α-fetoprotein (manufactured by Dako)
1000 ng / ml as mother liquor, dilution series 1000, 500, 250, 1
25, 62.5, 31.25, 15.63 and 7.81 ng / ml were prepared.

25 μl of each AFP solution and 25 μl of Latec reagent
1 was collected, mixed in a microplate, and allowed to stand for 1 hour to observe the aggregation image.

As a comparative example, Cellodia AFPmono
(Fujirebio) and the same test solution was measured according to a conventional method.

Table 4 shows the results.

[0078]

[Table 4]

The results also show that the colored polymer particles of the present invention are excellent.

[0080]

The colored polymer particles prepared by the emulsion polymerization method of the present invention have sufficient incorporation of the colorant into the particles, have a sharp particle size distribution, and have a toner for electrostatic charge developing and It is useful as a carrier for biological diagnostics.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-181302 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 2/00-2/60

Claims (6)

(57) [Claims] 1. An aqueous phase containing at least a polymerizable ethylenically unsaturated monomer and a water-soluble radical polymerization initiator,
In the process of forming polymer particles containing a colorant by emulsion polymerization, when the polymerization conversion rate is 20 to 85% ,
A dispersion in which a color pigment is dispersed in an aqueous system containing a surfactant is added , and the concentration of the surfactant in the aqueous phase is controlled.
Method for producing colored polymer particles, characterized in der Rukoto than field micelle concentration. 2. A method for producing colored polymer particles, wherein the aqueous dispersion of a color pigment contains a water-soluble radical polymerization initiator. 3. An aqueous phase containing at least a polymerizable ethylenically unsaturated monomer and a water-soluble radical polymerization initiator,
In the process of forming polymer particles containing a colorant by emulsion polymerization, when the polymerization conversion rate is 20 to 85% ,
A dispersion in which a color pigment is dispersed in an aqueous system containing a surfactant is added , and the concentration of the surfactant in the aqueous phase is controlled.
Colored polymer particles, characterized in that it is produced by reacting less than the field micelle concentration. 4. The colored polymer particles according to claim 3, wherein the aqueous dispersion of the color pigment contains a water-soluble radical polymerization initiator. 5. A toner for developing an electrostatic image, wherein the colored polymer particles according to claim 3 are used. 6. An immunoassay carrier comprising the colored polymer particles according to claim 3 or 4.