JPH05247108A - Colored polymer particle and its production - Google Patents

Abstract

PURPOSE:To obtain monodisperse colored polymer particles having a small particle diameter and an electrophotographic toner and an immunoassay carrier. CONSTITUTION:A colorant treated with a surface treating agent is dispersed in water and the emulsion polymerization is then carried out in the coexistence of an ethylenically unsaturated monomer and a water-soluble radical polymerization initiator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to polymer particles containing a pigment, and more particularly to colorant-containing polymer particles having a monodisperse particle size distribution by emulsion polymerization.

[0002]

As a method for producing polymer particles, an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method and the like are known. The particles produced by these polymerization methods have different particle sizes, particle size distributions, molecular weights, particle surface states, etc., and are used according to the purpose. In the emulsion polymerization method, the produced particles are high-molecular-weight monodisperse particles having a particle size of 1.0 μm or less.
On the other hand, the suspension polymerization method gives large particles of 10 μm or more, but the particle size distribution is polydisperse.

As a method for incorporating a colorant into the polymer particles, in the case of a suspension polymerization method, for example, in JP-A-2-67564, polymerization is carried out by adding an additive such as a colorant to a radical monomer. A method for obtaining polymer particles containing a colorant is described.

In the case of the emulsion polymerization method, for example, JP-A-1-093749
The publication describes a method of embedding or fixing a colorant to particles produced by an emulsion polymerization method by mechanical impact force or compression force.

[0005]

However, in the above prior art, the particle size of the colored polymer particles produced by the suspension polymerization method is limited to the range of 1 to 100 μm, and it is difficult to produce particles having a particle size of less than that. Is. Further, in the emulsion polymerization method, the colorant is exposed on the surface, so that the storage stability is poor.

Since the colored polymer particles of the present invention are produced by an emulsion polymerization method and thus have a fine particle size and a monodispersed distribution, they are used as electrophotographic toners, immunological diagnostic reagent carriers, and liquid crystal display panel gap adjustments. It can be used as an agent, standard particles for particle size measurement, chromatography filler, cosmetics filler, texture improver for synthetic leather, etc., and has a wide range of uses.

[0007]

OBJECTS OF THE INVENTION It is, therefore, an object of the present invention to provide colored polymer particles having a small particle size, monodispersion and containing a colorant by an emulsion polymerization method.

[0008]

In order to achieve the above objects, the colored polymer particles of the present invention use a colorant treated with a surface treatment agent, and preferably dispersed in water to obtain an ethylenic monomer. By carrying out emulsion polymerization in the coexistence of a saturated monomer and a water-soluble radical polymerization initiator, it was possible to obtain polymer particles containing a colorant. In the production method aspect
The concentration of the surface treatment agent is preferably 0.01 to 20 wt% with respect to the colorant. Further, the colored polymer particles are useful as a toner for electrophotography and a carrier for immunoassay.

The present invention will be specifically described below.

[Colored Polymer Particles] The colored polymer particles of the present invention are polymer particles obtained by polymerizing a polymerizable monomer, and the surface treatment is applied to the above-mentioned polymer particles. It is included.

[Dispersant] The concentration of the dispersant in the present invention is a concentration at which the colorant can be easily dispersed at the time of dispersing the colorant in the aqueous phase, and at the time of polymerization, particles of the colorant-containing particles are dispersed. Other than growth, it is below the concentration at which new particles are not formed in the aqueous phase.

Specifically, when the dispersant is a surfactant, it is shown that, when the colorant is dispersed in the aqueous phase, the surfactant present in the aqueous phase has a critical micelle concentration (CMC) or more. There is. In addition, during polymerization, the concentration of CMC or less, or the surfactant desorbed from the particle surface during the polymerization is CMC
It shows that the concentration does not exceed. This is because when the desorbed surfactant forms micelles above CMC, the unreacted monomer in the polymerization process causes emulsion polymerization in the micelles, promotes the generation of new particles, and is a polymer containing no colorant. This is because it results in the generation of particles.

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-dimethianiline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-6-sodium sulfonate, etc.), sulfuric acid Ester salts (sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.) Can be mentioned.

[Monomer] As the polymerizable monomer, a conventionally known one can be used, and particularly a radical polymerizable one is preferable. One kind or a combination of two or more kinds can be used so as to satisfy the required characteristics.

Specifically, a 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 or the like can be used.

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-hexylstyrene, p-
Octyl styrene, p-nonyl styrene, p-decyl styrene, p-dodecyl styrene, 2,4-dimethyl styrene, 3,4-
Examples thereof include styrene monomers such as dichlorostyrene and derivatives thereof.

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, β-hydroxyacrylate, γ -Propyl aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and the like.

Examples of the vinyl ester-based monomer 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,
Propylene, isobutylene, 1-butene, 1-pentene, 4-
Examples thereof include mono-olefin type monomers such as methyl-1-pentene and di-olefin type monomers such as butadiene, isoprene and chloroprene.

Further, a crosslinkable monomer may be added to improve the characteristics of the polymer particles. Examples of the crosslinkable monomer include those containing 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,
It is possible to use a monomer having a functional group.

[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.), per Examples thereof include oxide compounds.

Further, the above-mentioned 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.
A range of 50 ° C to 80 ° C is used. However, it is also possible to polymerize at room temperature or higher temperature by using a combination of a polymerization initiator that starts at room temperature, for example, hydrogen peroxide-reducing agent (ascorbic acid, etc.).

[Coloring Agent] As the coloring agent, conventionally known coloring agents can be used. Although any coloring agent can be used, specifically, an inorganic or organic pigment is preferably used.

Examples of black colorants include furnace black, channel black, acetylene black, thermal black, lamp black and the like.

As the pigment for magenta or red,
C. 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: 1, C.I. I. Pigment Red 53: 1, C.I. I. Pigment Red 57: 1, C.I. I.
Pigment Red 122, C.I. I. Pigment Red 123,
C. 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 178, C.I. I. Pigment Red 2
22 etc. are mentioned.

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.

As a pigment for green or cyan,
C. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 15: 3, C.I. I.
Pigment Blue 16, C.I. I. Pigment Blue 60,
C. I. Pigment Green 7 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 about 2 to about 20 relative to the polymer.
Parts, preferably about 3 to 15 parts are selected.

[Surface Treatment Agent] As the surface treatment agent for the pigment, conventionally known agents can be used. Specifically, silane compounds, titanium compounds and the like can be preferably used.

As the silane compound, alkoxysilane such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, diphenyldimethoxysilane, silizane such as hexamethyldisilazane, γ-chloropropyltrimethoxysilane and vinyltrichlorosilane. , Vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane,
Examples include γ-aminopropyltriethoxysilane and γ-ureidopropyltriethoxysilane.

As the titanium compound, for example, TTS, 9S, 38S, 41B, 46B, 55, 138S, 238S, which is commercially available under the trade name "Planeact" manufactured by Ajinomoto Co., Inc.
Etc., commercial products A-1, B-1, TOT, T manufactured by Nippon Soda Co., Ltd.
ST, TAA, TAT, TLA, TOG, TBSTA,
A-10, TBT, B-2, B-4, B-7, B-10, T
BSTA-400, TTS, TOA-30, TSDMA, T
Examples include TAB and TTOP.

[Production Method of Colored Polymer Particles] The production method of the colored polymer particles of the present invention comprises dispersing a colorant treated with a surface treatment agent into a water phase in which a water-soluble radical polymerization initiator is dissolved, A method for obtaining colored polymer particles by dropping an ethylenically unsaturated monomer and performing emulsion polymerization, wherein the colorant is contained in the polymerized particles.

The colored polymer particles of the present invention thus produced are electrophotographic toner, carrier for immunological diagnostic reagent, gap adjusting agent for liquid crystal display panel, standard particle for particle size measurement, packing for chromatography. It can be used as an agent, 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 resin for pulverized toner but also as a polymerized toner.

When the colored 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. As the above ingredients,
Examples include charge control agents and fixing improvers. These components can be introduced by adding desired contents to the polymerizable monomer.

Further, when the colored polymer particles of the present invention are used as a toner for electrophotography, a post-additive (referred to as an external additive) for improving fluidity and chargeability may be blended and used. it can.

[Fixing Improver] As the fixing improver, known compounds 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, etc. are used.

[Charge Control Agent] As the charge control agent, known ones are 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 here means a group having a charge regardless of positive or negative, such as a carboxyl group, a sulfonic acid group, an amino group, an ammonium base and the like.

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. Examples thereof include electron-accepting organic complexes having negative chargeability such as activators, chlorinated paraffins, chlorinated polyesters, and sulfonylamines of copper phthalocyanine.

[External Additive] As the external additive, for example, a fluidizing agent,
There are fine particles such as charge control agents and lubricants. Examples of the fluidizing agent include inorganic fine powders such as hydrophobic silica, titanium oxide, alumina and their sulfides, nitrides and silicon carbide. As the charge control agent, polyvinylidene fluoride,
Examples thereof include polystyrene powder, polymethylmethacrylate powder, and polyethylene fine particles. Examples of lubricants include fatty acid metal salt fine powder and the like.

Carrier for Immunological Diagnostic Agent: The polymerized colored 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. Used.

As the 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 in which it is physically adsorbed and immobilized on a hydrophobic surface. For example, it is easy and immunological by using polymer particles using styrene and its derivatives, acrylic acid ester, methacrylic acid ester, etc. Active sites such as (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, for example, 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 above functional group may be added as a comonomer during the 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 or 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 a monoclonal antibody is used, it is preferable to mix and use several kinds of antibodies having different binding sites for an antigen.

[0050]

EXAMPLES The present invention will be described in detail with reference to examples.

Example 1 [Pigment surface treatment method] 200 ml of hexane and 20 g of pigment were added to a cylindrical separable flask having an internal volume of 500 ml, and 2 wt% of the surface treatment agent was added to the pigment under a nitrogen stream. 200r
While stirring at a stirring speed of pm, the temperature inside the flask was raised to 68 ° C. In this state, the reaction is continued for 2 hours to complete the reaction. The treated pigment is filtered and dried under reduced pressure at 120 ° C.

[Preparation of Pigment Dispersion Liquid] To 1.78 g of the pigment, 0.35 g of sodium dodecylbenzenesulfonate and 50 ml of degassed ion-exchanged water were mixed, and then a pigment dispersion liquid was prepared using an ultrasonic dispersion device. The results are shown in Table 1.

[0053]

[Table 1]

[Synthesis of Colored Polymer Particles] A cylindrical separable flask having an internal volume of 500 ml was equipped with a temperature sensor, a nitrogen introducing tube, and
A polymerization reactor equipped with a stirring device (with a disc turbine type stirring blade) was prepared. 250 ml of degassed deionized water and 5 g of potassium persulfate were added, and the inside of the flask was heated to 70 ° C while stirring at 300 rpm under a nitrogen stream. When the internal temperature rose to 70 ° C, 30 g of styrene monomer was added to the separatory funnel at 0.7 ml / mi.
Polymerization was initiated by adding at a rate of n. Polymerization was carried out for 7 hours to complete the polymerization. Generated particles are laser diffraction type particle size measuring device S
Table 2 shows the results of measurement using ALD-1100 (manufactured by Shimadzu Corporation).

[0055]

[Table 2]

As shown in Table 2, the colored polymer particles of the present invention can form fine particles having very high monodispersity. On the other hand, CL-005 and 006 of the comparison have a large amount of the dispersant or the polymerization initiator added, and polymer single particles are generated.
You can see that they are not mixed well.

Example-2 The colored polymer particles CL-001 to 004 prepared in Example-1 were used to agglomerate as described in JP-A-60-220358, followed by drying and crushing to obtain average particles. The diameter was 5 μm.
This was designated as CLT-001 to 004. To this toner, 2% by weight of silica and 1% by weight of titanium oxide were added and mixed,
A developer was prepared by mixing 5 parts of this externally added toner with 95 parts of ferrite particles (carrier) surface-coated with a methyl methacrylate / styrene copolymer.

For comparison, styrene / butyl acrylate = 85/15 (wt%), C.I. B. Was used in the same amount as CL-001 to prepare a toner having an average particle size of 5 μm by a kneading and pulverizing method, and the same treatment was performed to obtain a comparative developer.

An electrophotographic copying machine "U-Bix" using the above developer and equipped with a heat roller fixing device and a cleaning blade.
3032 ”(manufactured by Konica Corp.) was subjected to a live-copy test for forming a copy image, and the following items were evaluated.

(1) Resolution A copy image of a fine line chart was formed and judged by the number of distinguishable fine lines per 1 mm.

(2) Fogging Copy images are continuously formed in a normal temperature and normal humidity environment (temperature 20 ° C., relative humidity 60%), and “Sakura Densitometer PDA-6
"0" (manufactured by Konica Corporation) 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 due to hot offset occurs is measured and shown. It was

(4) Toner Coloring A single layer of toner was attached to a white label, and this toner layer was labeled "Sakura Densitometer PDA-60" (Konica Corp.).
Manufactured) and the reflection density of each color was measured, and the reflection density was 1.
3 or more was marked with ◯, and 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 based on the change in the number% of toner particles having a volume average diameter of 1/3 or less. In the actual copying test, the particle size distribution was measured with the passage of time, and it was shown that the number% of the toner was ⅓ or less of the volume average diameter at the start, when fog occurred, and when 50,000 copies were made. A laser diffraction particle size analyzer SALD-1100 (manufactured by Shimadzu) was used for the measurement. The results are shown in Table 3.

[0066]

[Table 3]

As is clear from Table 3 above, the toner using the colored polymer particles of the present invention has not only performance comparable to that of the kneading and pulverizing toner, but also the particle size distribution in the actual copying test. It can be seen that the toner is a good toner with little change. In particular, the number% of toner particles having a volume average diameter of 1/3 or less
It is known that if it exceeds 10%, the charging property of the toner is hindered. From this point as well, it is understood that the colored polymer particles of the present invention are more stable than the comparative toner.

Example-3 Colored polymer particles CL-00 of the present invention produced in Example-2.
1 (black) was prepared as an immunodiagnostic particle according to the following formulation. The colored particles CL-001 of the present invention were put in a cellulose dialysis bag having a molecular weight cut off of 1000, and dialyzed pure for 24 hours, and then concentrated to a solid content concentration of 5% using an ultrafiltration device. Add buffer and sodium chloride to this, 0.1MPB
Suspended in S.

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 AFP immunodiagnostic reagent. Dilution series 1000, 500, 25 using purified human α-fetoprotein (manufactured by Dako) as the mother liquor at 1000 ng / ml
0,125,62.5,31.25,15.63,7.81ng / ml was prepared.

25 μl of each AFP solution and 25 latex reagents
μl was taken out, mixed in a microplate, allowed to stand for 1 hour, and the aggregated image was observed. Targeted Therodia AFPmo
A similar test solution was measured according to a conventional method using no (manufactured by Fujirebio). The results are shown in Table 4 below.

[0072]

[Table 4]

[0073]

According to the constitution of the present invention, the colored polymer particles having a small particle diameter and being monodisperse 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.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location G01N 33/545 B 9015-2J (72) Inventor Jiro Takahashi 2970 Ishikawacho, Hachioji, Tokyo Konica Stocks In the company

Claims (6)

[Claims] 1. A method for producing colored polymer particles, which comprises performing emulsion polymerization using a colorant treated with a surface treatment agent. 2. The surface treatment agent concentration is 0.01 to the colorant.
The method for producing colored polymer particles according to claim 1, wherein the treatment is carried out at a concentration of 20 wt%. 3. A colorant treated with a surface treatment agent is dispersed in water, emulsion polymerization is carried out in the coexistence of an ethylenically unsaturated monomer and a water-soluble radical polymerization initiator, and the colorant is added to the polymer particles. The method for producing colored polymer particles according to claim 1, wherein the colored polymer particles are contained. 4. Colored polymer particles produced by the production method according to claim 1, wherein emulsion polymerization is carried out using a colorant treated with a surface treatment agent. 5. An electrophotographic toner using the colored polymer particles. 6. A carrier for immunoassay using the colored polymer particles.