JPH05222109A - Monodisperse colored polymer particle produced by seed polymerization and production thereof - Google Patents

Abstract

PURPOSE:To obtain monodisperse colored polymer particles having a large particle diameter by seed polymerization in which particles of a polymer of an ethylenic monomer are used as seed particles to polymerize an ethylenic monomer, by adding an aqueous pigment dispersion at a specific stage of the polymerization. CONSTITUTION:To a substantially dispersant-free dispersion of a polymer comprising the unit of an ethylenic monomer (a) is added an ethylenic monomer which is the same as and/or different from the monomer (a). Seed polymerization is then initiated with the aid of a water-soluble, free-radical polymerization initiator. An aqueous pigment dispersion is added when the conversion has reached about 20-85%, and the polymerization is carried out at a specific temp., thereby giving the title particles having a large particle diameter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a monodispersed and large particle size colored polymer particle, and more particularly to a spherical colored polymer particle having a monodisperse particle size distribution and a particle size of micron.

[0002]

2. Description of the Related Art Conventionally, emulsion polymerization method, suspension polymerization method, dispersion polymerization method and the like are known for spherical particles. Each of these polymerization methods has advantages and disadvantages, and is characterized by the obtained particle size, particle size distribution, molecular weight, and particle surface state. By the emulsion polymerization method, high molecular weight monodisperse particles can be easily obtained, but only fine particles having a particle size of 1.0 μm or less can be obtained. On the other hand, the suspension polymerization method gives large particles of 10 μm or more, but the particle size distribution is polydisperse. Further, the dispersion polymerization method is known to obtain particles having a particle size on the order of micron, but the monomers constituting the polymer particles are limited, and it is not easy to control the molecular weight and the particle size. Since an organic solvent is used as the solvent, there is a concern about environmental problems, and selection of these is limited similarly to the monomer.

Further, the polymer dispersant often used in the suspension polymerization method and the dispersion polymerization method often adheres to the particle surface and is difficult to be easily removed from the particle interface. The phenomenon of exhibiting different properties from is often observed.

To improve these drawbacks, for example, according to Journal of Polymer Science; Polymer Symposium, 72 , 225-240 (1985), polymer particles prepared by an emulsion polymerization method are used as an oligomer or A "two-step swelling method" has been proposed in which the solvent is swollen, and then the monomer is swollen to perform polymerization.

[0005]

However, the above-mentioned method of the prior art not only requires a complicated technique of two-step swelling but also requires a long time for the swelling process itself, which significantly increases the productivity. It has the drawback of chipping.

Since monodisperse particles having a particle size of several μm or more do not require classification operation, they are used as electrophotographic toners, gap control agents for liquid crystal display plates, medical diagnostic carriers, standard particles for particle size measurement, and chromatography. It has a wide range of uses, such as fillers for cosmetics, fillers for cosmetics, and texture modifiers for synthetic leather.

Accordingly, it is an object of the present invention to provide colored polymer particles of monodisperse and large particle size.

Another object of the present invention is to provide monodisperse and large particles which meet the above purpose of use.

[0009]

[Means for Solving the Problems] As a result of extensive studies in accordance with the above object, a polymer particle dispersion liquid containing substantially no dispersant was found to contain an ethylenically unsaturated monomer unit constituting the polymer particles. Monodispersed and large-sized polymer particles obtained by seed polymerization in the presence of a water-soluble radical polymerization initiator by adding the same and / or different ethylenically unsaturated monomers,
With the polymerization addition rate of seed polymerization being about 20 to about 85%,
Achieved by monodisperse and large-sized colored polymer particles, characterized by being obtained by adding an aqueous pigment dispersion.

[0010]

[Action]

(Dispersant) The polymer particle dispersion liquid substantially free of a dispersant in the present invention represents a dispersion liquid containing seed particles,
Further, the state of substantially containing no dispersant means a concentration not higher than the concentration at which new particles are not generated in the aqueous phase, except for the polymerization reaction in which the particle size growth of seed particles occurs during seed polymerization.

Specifically, when the dispersant is a surfactant,
The surfactant present in the water phase is the critical micelle formation concentration (CM
C) It shows that it is the following. At this time, the amount of the surfactant adsorbed on the polymer particles is stopped to such an extent that it does not matter, or the surfactant desorbed from the particle surface during the polymerization process does not exceed CMC. This is because when the desorbed surfactant forms micelles above CMC, the unreacted monomer in the polymerization process promotes emulsion polymerization in the micelles in parallel and promotes the production of new particles. This is because it results in generation of dispersed polymer particles.

The concentration of the dispersant is preferably CMC or less, and more preferably it is absent.

As the dispersant, a water-soluble polymer (gelatin,
Tragacanth gum, starch, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid salts, etc., sparingly soluble inorganic compound in the form of fine powder (barium sulfate, calcium sulfate, barium carbonate, calcium carbonate, magnesium carbonate, magnesium carbonate, magnesium carbonate, Calcium phosphate, talc, bentonite, diatomaceous earth, clay, etc.) and the like.

Further, surfactant sulfonates (sodium dodecylbenzene sulfonate, sodium arylalkyl polyether sulfonate, 3,3-disulfone diphenylurea-4,4-diazo-bis-amino-8-naphthol-6) -
Sodium sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol disulfonate sodium etc.), sulfate ester salt ( Sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.) and fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.).

(Seed Particles) The polymer particles according to the present invention may be prepared by any of emulsion polymerization method, suspension polymerization method and dispersion polymerization method, and may be used arbitrarily. This is because, by performing the seed polymerization of the present invention, the particle size distribution works in a direction narrowing with respect to the original seed particles.

However, since a complicated step of removing a dispersant, a solvent and the like used in the production of polymer particles which are suspension polymerization methods and dispersion polymerization method seed particles is required, it is preferably adjusted by an emulsion polymerization method. The polymer particles thus obtained are used as seed particles. Further, even if it is prepared by an emulsion polymerization method, it is necessary to remove the surfactant by using an appropriate means such as dialysis or ultrafiltration in consideration of the concentration of the above-mentioned dispersant. Therefore, more preferably, polymer particles prepared by the soap-free emulsion polymerization method are used as seed particles.

The polymer particles prepared by the soap-free emulsion polymerization method do not require a pretreatment step such as removal of a dispersant, have a clean particle surface, and have a particle size distribution adjusted by a usual emulsion polymerization method. It is more effective because it exhibits good monodispersity as compared with the above.

(Monomer) The ethylenically unsaturated monomer used in the present invention can be freely selected as long as it is radically polymerizable. For example, monovinyl aromatic monomer,
(Meth) acrylic acid ester monomer, vinyl ester monomer, vinyl ether monomer, monoolefin monomer, diolefin monomer, halogenated olefin monomer, polyvinyl monomer The body etc. are mentioned.

Examples of vinyl aromatic monomers include:
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-butylstyrene, pt-butylstyrene, p
-Hexyl styrene, p-octyl styrene, p-nonyl styrene, p-decyl styrene, p-dodecyl styrene, 2,4-dimethyl styrene, styrene monomers such as 3,4-dichloro styrene and derivatives thereof. Be done.

As the acrylic monomer, 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, ethyl β-hydroxyacrylate, γ-aminoacrylate propyl, stearyl methacrylate, methacrylic Examples thereof include dimethylaminoethyl acid salt and diethylaminoethyl methacrylate.

Examples of vinyl ester-based monomers include vinyl acetate, vinyl propionate, vinyl benzoate and the like.

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

As the olefinic monomer, ethylene,
Examples include monoolefin-based monomers such as propylene, isobutylene, 1-butene, 1-pentene, and 4-methyl-1-pentene, and diolefin-based monomers such as butadiene, isoprene, and chloroprene.

Further, a crosslinkable monomer may be added to improve the characteristics of the polymerized particles. Examples of the crosslinkable monomer 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.

The monomers of the present invention can be used alone or in combination of two or more depending on the purpose. Further, if necessary, a water-soluble monomer, an ionic monomer, or a monomer having a functional group can be used. The added monomer used in the seed polymerization of the present invention may be the above-mentioned monomer. At this time, it may be the same as or different from the monomer unit constituting the seed particles.

The addition amount of the monomer used for the seed polymerization can be freely selected within the range where the particle size distribution is not widened. In order to suppress the generation of new particles, it is necessary to add it within a range not exceeding the critical amount shown by the following formula (1).

V _m / S _a = 6.869 × 10 ⁻⁷ (1) However, in the above formula, V _m is the monomer volume () that can be added to the polymer particle dispersion liquid without generation of new particles ( represent critical amount), S _a represents the total surface area of the polymer particles in the polymer particle dispersion.

If the addition amount satisfies this condition, it is possible to generate larger particles by repeating the seed polymerization.

(Polymerization Initiator) The radical polymerization initiator used in the present invention can be appropriately used if it is water-soluble.
For example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4′-azobis-4-cyanovaleric acid and its salts, 2,2′-azobis (2-amidinopropane) salt, etc.), persulfates Examples thereof include oxide compounds.

Further, the above water-soluble radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. By using the redox type initiator, the polymerization activity can be increased and the polymerization temperature can be lowered, and further shortening of the polymerization time can be expected.

As the polymerization temperature, any temperature may be selected as long as it is at least the minimum radical generation temperature of the polymerization initiator, but for example, the range of 50 ° C. to 80 ° C. is usually used. However, it is also possible to carry out the polymerization at room temperature or lower by using a combination of a polymerization initiator which starts at room temperature, for example, hydrogen peroxide-reducing agent (ascorbic acid etc.).

(Seed polymerization production step) In the seed polymerization of the present invention, a step of adding a monomer in an amount equal to or less than the critical monomer amount into the seed particle dispersion, a step of uniformly agitating the added monomer into the dispersion, and a step of raising the temperature to the polymerization temperature are carried out. The process consists of heating and adding an initiator and polymerizing. This can be easily achieved by repeating the above step once or more in order to obtain polymer particles having a required particle size.

(Pigment Aqueous Dispersion) Inorganic and organic pigments are used by being dispersed in water using a known low-molecular or high-molecular dispersant according to a conventional method. At this time, it is not preferable to use a necessary amount of dispersant or more, for example, to disperse the surfactant in a concentration higher than the critical micelle formation concentration (abbreviated as CMC). This is because the added ethylenically polymerized monomer is taken into the activator micelle, and there is a concern that new particles will be generated.

The pigment may be selected from cationic, anionic and nonionic ones as necessary. Further, a water-soluble polymer activator is also applicable. These have a polymerization rate of 20%
It is added at 85%.

When the amount is less than that, the progress of polymerization is hindered, and when the amount is more than that, the produced polymer particles are aggregated, the monodispersity is impaired, and no particles can be obtained at all.

It is preferable that the dispersant has a critical micelle formation concentration or more at the time of dispersing the pigment, and it is preferably not more than the critical micelle formation concentration at the time of addition at the time of seed polymerization. Thereby, the generation of new particles is remarkably suppressed and the monodispersity can be maintained.

Specific examples of the dispersant include dodecylbenzene sulfonate, dodecyl sulfate, cetyl trimethyl ammonium salt, polyvinyl alcohol and the like.

The large particle size and monodisperse polymer particles of the present invention produced as described above are used for electrophotographic toners, carriers for immunological diagnostic reagents, gap adjusting agents for liquid crystal display plates, and particle size measuring agents. It can be used as a standard particle, a filler for chromatography, a filler for cosmetics, a texture modifier for synthetic leather, and the like.

Toner for electrophotography: When used as a toner for electrophotography, it is useful not only as a binder resin for a pulverized toner but also as a polymerized toner.

When the polymer particles of the present invention are used as a toner for electrophotography, it is necessary to include a component to be added as a toner in the polymer. Examples of the above components include a colorant, a charge control agent, and a fixing property improver. For example, pigments are achieved by incorporating the desired content during seed particle preparation. Of course, other components can be introduced into the polymer particles as well.

(Colorant) As the colorant, dyes and pigments are generally used, but pigments having high weather fastness are widely used. Examples of the pigment include black pigments such as carbon black and graft-treated carbon black, and examples of color pigments such as cyan or green pigment include C.I. I. Pigment Blue-15, C.I. I. Pigment Blue-15: 2,
C. 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.

Examples of magenta or red pigments include C.I. I.
Pigment Red 2, C.I. I. Pigment Red 3,
C. 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: 1, C.I. I. Pigment Red 53: 1, C.I. I. Pigment Red 57: 1,
C. I. Pigment Red 122, C.I. I. Pigment Red 123, 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. I. Pigment Red 1
78, C.I. I. Pigment Red 222 and the like.

Yellow or orange pigments include 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 13
8, C.I. I. Pigment Orange 31, C.I. I. Pigment Orange 43 and the like.

These organic and inorganic pigments can be adjusted to a desired color tone by selecting one or a plurality of them in combination as desired.
The amount of pigment added is selected from about 2 to about 20 parts, preferably about 3 to 15 parts, relative to the polymer. Further, in order to enclose the pigment in the particles produced by emulsion polymerization, it is possible to perform a known surface treatment. As the surface treatment agent, a silane coupling agent or a metal salt of higher fatty acid is used.

(Fixing property improver) As the fixing property improver,
Known ones are used. Generally, a polyolefin type is used. For example, low-molecular-weight polyethylene, low-molecular-weight polypropylene, oxidized polyethylene and polypropylene, acid-modified polyethylene, and polypropylene are used. These can be introduced into polymer particles by a conventional method, after being melted, dispersed in water and added in the form of emulsion during emulsion polymerization or seed emulsion polymerization. It is preferable to add it during seed emulsion polymerization so that it can be made to exist as polyolefin fine particles on the particle surface, which is preferable from the viewpoint of improving fixability.

Further, a polyethylene wax emulsion marketed under the trade name "HYTEC" (manufactured by Toho Chemical Industry Co., Ltd.) can be used for the same purpose.

(Charge Control Agent) A charge control agent having a known structure is also used. However, it may not be necessary when the monomer having a polar group is copolymerized on the surface of the polymer particles. The polar group as used herein refers to a group having a charge regardless of whether it is positive or negative, such as a carboxyl group, a sulfonic acid group, an amino group, or an ammonium base.

As the charge control agent, a nigrosine-based electron-donating dye, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylated amine, a quaternary ammonium salt, an alkylamide, a metal complex, a pigment, or a fluorine treatment is used as a charge control agent. An electron-accepting organic complex such as an activator, which is negatively charged
Examples thereof include chlorinated paraffin, chlorinated polyester, and sulfonylamine of copper phthalocyanine.

Carrier for Immunological Diagnostic Agent: The polymer particles of the present invention are useful as a carrier for immunological diagnostics because of their uniform particle size and the fact that the particle surface is not contaminated by contaminants. Be done.

As a carrier for immunological diagnosis, it is necessary to immobilize an immunologically active substance such as an antigen, an antibody or a receptor on the particle surface. Physical immobilization methods and chemical immobilization methods are known for immobilization of immunologically active substances.
The former is a method of physically adsorbing and immobilizing it on a hydrophobic surface. For example, by using polymer particles using styrene and its derivatives, acrylic acid ester, methacrylic acid ester, etc., it is possible to easily and immunologically. Active site eg (Fa
b) 'can be immobilized in a form that does not adsorb. As a matter of course, when IgG is used as the antibody, (Fab ′) ² or Fab ′ obtained by digesting the Fc fragment can also be used.

Further, in the case of the chemical immobilization method, the polymer particles 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 are used,
It is possible to immobilize it by covalent bonding by reacting an immunologically active substance using a known bifunctional reagent.

At this time, the polymerizable monomer having the functional group may be added as a comonomer during seed polymerization. The amount of the functional group-containing monomer can be appropriately determined according to need, but it is preferably selected from the range of, for example, about 0.1% to 15%.

As the antibody to be used, a polyclonal antibody and a monoclonal antibody can be appropriately selected, but a polyclonal antibody is preferable when used in an agglutination test or an agglutination inhibition test. When using a monoclonal antibody, it is preferable to use a mixture of several antibodies having different binding sites for the antigen.

[0054]

【Example】

Example 1 (Synthesis of seed latex particles) A cylindrical separable flask having an inner volume of 500 ml was equipped with a temperature sensor, a nitrogen introducing tube, and a stirring device.
A polymerization reactor equipped with a disc turbine type stirring blade and equipped with four baffle plates inside the flask was facilitated. 32 ml of distilled styrene monomer was added to 318 ml of degassed ion-exchanged water, and the temperature inside the flask was raised to 70 ° C. while stirring at a stirring speed of 200 rpm under a nitrogen stream. When the internal temperature had risen to 70 ° C., an initiator aqueous solution prepared by dissolving 1.62 g of potassium persulfate in 50 ml of degassed deionized water was added to initiate polymerization.

While maintaining this state, polymerization was carried out for 7 hours to complete the reaction. The produced latex particles were measured with a laser diffraction particle size analyzer SALD-1100 (manufactured by Shimadzu Corporation), and the average particle size d ₅₀ = 1.1 μm CV value (σ d ₅₀ / d ₅₀ ) was 0.
It was 21.

(Measurement of polymerization rate in seed emulsion polymerization)
A polymerization reactor similar to that used for the synthesis of seed latex particles was prepared. As the seed particles, 7.26 g of the polystyrene seed particles having the average particle diameter of 1.1 μm was used. A certain amount of seed particles, 32 ml of styrene monomer, and 168 ml of degassed deionized water were added to the polymerization reactor, and the mixture was stirred at a stirring speed of 200 rpm. The temperature inside the flask was further raised to 70 ° C, 1.62 g of potassium persulfate was added to 50 ml of degassed deionized water, an initiator aqueous solution was added, polymerization was carried out for 7 hours under a nitrogen stream, and sampling was carried out over time. The polymerization rate was investigated according to a conventional method. It was found that the polymerization rate in seed emulsion polymerization was between 20% and 85% between about 50 minutes and 280 minutes after the start of seed emulsion polymerization. Further, even when the monomer composition was changed to styrene / n-butyl acrylate = 85/15, the time was almost the same.

(Preparation of Pigment Dispersion) After mixing 16.2 g of pigment with 3.15 g of sodium dodecylbenzenesulfonate and 300 ml of degassed ion-exchanged water, a pigment dispersion was prepared using an ultrasonic dispersing device. The results are shown in Table 1.

[0058]

[Table 1]

(Synthesis of Pigment Composite Particles) Polystyrene seed particles [S-01: average particle size 1.1 μm, CV (coefficient of variation) value 0.21] and copoly (styrene / n-butyl acrylate) synthesized by the above-described formulation. ) Seed particles [S-02: St / n-BA
= 85/15, average particle size 0.68 μm, CV value 0.20] as particles
Using 7.26 g, seed particles, monomer 29.06 g, degassed ion-exchanged water 168 m in a polymerization reactor according to the recipe of seed emulsion polymerization.
l was added and stirred at a stirring speed of 200 rpm. Further, the temperature inside the flask was raised to 70 ° C., and an initiator aqueous solution obtained by dissolving 1.62 g of potassium persulfate in 50 ml of degassed deionized water was added to initiate polymerization. After the initiation of the polymerization reaction, the pigment dispersion was appropriately added into the polymerization reaction device according to the measurement of the polymerization rate. The pigment dispersion was added such that the pigment weight was 2.90 g. The results are shown in Table 2.

[0060]

[Table 2]

As shown in Table 2, the colored particles of the present invention can be produced with extremely high monodispersity. On the other hand, it can be seen that the comparative T-008,009 cannot be complexed well when the pigment dispersion is too early or too late.

Example-2 Monodisperse colored particles T-004 to 00 prepared in Example-1
No. 7 was used to agglomerate as described in JP-A-3-259156, followed by drying and crushing to obtain an average particle size of about 5 μm.
This was designated as TK-001 to 004. To this toner, 2% by weight of silica and 1% by weight of titanium oxide were added and mixed, and 5 parts of this externally added toner and methyl methacrylate /
A developer was prepared by mixing 95 parts of ferrite particles (carrier) surface-coated with a styrene copolymer.

For comparison, styrene / n-butyl acrylate = 85/15 (wt%), carbon black content is T-001
A toner having an average particle diameter of about 5 μm was prepared by the kneading and pulverizing method in the same amount as above, and the same treatment was performed to obtain a comparative developer. An electrophotographic copying machine "U-Bix3032" (Konica Corporation) using the above-mentioned developer and equipped with a heat roller fixing device and a cleaning blade.
(Manufactured by Mfg. Co., Ltd.), a real-life test for forming a copy image was performed and the following items were evaluated. (1) Resolution A copy image of a thin line chart was formed and judged by the number of distinguishable thin lines per 1 mm.

(2) Fogging Copy images are continuously formed under normal temperature and normal humidity environment (temperature 20 ° C., relative humidity 60%), and “Sakura Densitometer PDA-6
"0" (manufactured by Konica Corp.) was used to measure the reflection density of each color in the white background portion, and the fog was judged by the number of copies when the reflection density exceeded 0.02.

(3) Offset Occurrence Temperature The set temperature of the fixing roller is changed stepwise to form a copy image, and the set temperature of the fixing roller at the time when toner stain caused by hot offset occurs is measured. It was

(4) Coloring degree of toner A single layer of toner was attached to a white label, and the reflection density of each color was measured for this toner layer using a "Sakura densitometer PDA-60". A value of 1.3 or less was marked with x.

(5) Cleaning Property The surface of the photoconductor was visually observed and evaluated by the number of copies when the cleaning failure occurred.

(6) Change in particle size distribution Evaluation was made by the change in the number% of toner particles having a volume average particle size of 1/3 or less. In the actual copying test, the particle size distribution was measured over time, and it was shown that the number% of the toner was 1/3 or less of the volume average particle size at the start, at the time of fogging, and at 50,000 copies. Laser diffraction type particle size distribution analyzer SALD-110
0 (manufactured by Shimadzu Corporation) was used. The results are shown in Table 3.

[0069]

[Table 3]

As is clear from Table 3 above, the polymerized toner of the present invention is a good toner that not only has performance comparable to that of the kneaded and pulverized toner, but also has a small change in particle size distribution in the actual copying test. I know there is something. In particular, it is known that if the number% of toner particles having a volume average particle diameter of 1/3 or less exceeds 10%, the charging property of the toner is hindered. From this point, it is apparent that the polymerized toner of the present invention is more stable than the comparative toner.

Example-4 Color particles T-001 of the present invention prepared in Example-2
(Black) was prepared as particles for immunodiagnosis according to the following formulation. The colored particles S-09 of the present invention were placed in a cellulose dialysis bag having a molecular weight cut off of 1000, and dialyzed against pure water for 24 hours.
Concentration was performed to a solid content of 5% using an ultrafiltration device.
A buffer and sodium chloride were added to this, and the suspension was suspended in 0.1 M PBS.

An anti-α-fetoprotein antibody (IgG fraction) was added to this dispersion and physical adsorption was carried out at 4 ° C. for 24 hours.

This is used as a polymer solid content of 0.2% of 0.1M.
Was diluted with PBS (pH = 7.2) to prepare an immunodiagnostic reagent for AFP. Purified human α-fetoprotein (manufactured by Dako)
1000ng / ml as mother liquor, dilution series 1000,500,250,125,
62.5, 31.25, 15.63, 7.81 ng / ml were prepared.

25 μl of each AFP solution and 25 latex reagents
μl was taken, mixed in a microplate, allowed to stand for 1 hour, and the aggregated image was observed. Therodia AFP as a target
The same test solution was measured using mono (manufactured by Fujirebio) according to a conventional method. The results are shown in Table 4 below.

The kit of the present invention comprises AFP1000 to 15.63 ng / ml.
Up to 7.81ng / ml below the cutoff value
Shows a negative result.

On the other hand, the comparative kit exhibited the prozone phenomenon at 1000 ng / ml, and no clear aggregation image was obtained.
Even at the low value of 15.63 ng / ml, no clear agglutination image was observed and the detection limit was low.

[0077]

[Table 4]

[0078]

EFFECTS OF THE INVENTION According to the constitution of the present invention, colored polymer particles having a monodisperse property and a large particle size can be formed easily with good reproducibility. Moreover, the colored polymer particles have excellent performance as a toner for electrophotography and a carrier for immunoassay.

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Claims (7)

[Claims] 1. An ethylenically unsaturated monomer which is the same as and / or different from the ethylenically unsaturated monomer unit constituting the polymer particles is added to a polymer particle dispersion liquid containing substantially no dispersant. In the monodisperse and large-sized polymer particles obtained by seed polymerization in the presence of a water-soluble radical polymerization initiator,
When the polymerization conversion rate of seed polymerization is about 20 to about 85%,
Colored polymer particles of a monodisperse and large particle size, which are obtained by adding an aqueous pigment dispersion. 2. The monodisperse and large particles according to claim 1, wherein the polymer particles are polymer particles produced by at least one polymerization method of emulsion polymerization, suspension polymerization and dispersion polymerization. Colored colored polymer particles. 3. The monodisperse and large amount according to claim 1, wherein at least 50% by weight or more of the ethylenically unsaturated monomer added is a hydrophobic ethylenically unsaturated monomer. Colored colored polymer particles. 4. The addition amount V _m of the ethylenically unsaturated monomer to be added is not more than a critical amount determined by the following formula (1) with respect to the total surface area S _a of the polymer particles. The monodispersed and large-sized colored polymer particles according to claim 1, 2, or 3. V _m = S _a × 6.869 × 10 ⁻⁷ (1) (where V _m : critical addition amount of monomer, S _a : total surface area of seed particles) 5. An electrophotographic toner using the colored polymer particles. 6. A carrier for immunoassay using the colored polymer particles. 7. A step of adding a) an ethylenically unsaturated monomer unit to an aqueous dispersion of polymer particles which does not substantially contain a dispersant, and homogenizing. b) A step of raising the temperature to the polymerization initiation temperature and adding the radical polymerization initiator aqueous solution. c) adding the aqueous pigment dispersion at a polymerization conversion of about 20 to about 85%. d) A step of completing the polymerization at a constant polymerization temperature. 1. A process for producing monodispersed and large-sized colored polymer particles, which comprises: