JP3252231B2 - 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 a pigment-containing polymer particle, and more particularly to a colorant-containing polymer particle having a monodispersed particle size distribution by emulsion polymerization.

[0002]

2. Description of the Related Art Emulsion polymerization, suspension polymerization, dispersion polymerization and the like are known as methods for producing polymer particles. Particles produced by these polymerization methods have different particle sizes, particle size distributions, molecular weights, surface states of the particles, and the like, and are used according to purposes. In the emulsion polymerization method, the generated particles are monodisperse particles having a particle size of 1.0 μm or less and high molecular weight.
On the other hand, in the suspension polymerization method, large particles of 10 μm or more are obtained, but the particle size distribution is polydisperse.

As a method for incorporating a colorant into polymer particles, in the case of a suspension polymerization method, for example, Japanese Patent Application Laid-Open No. 2-167564 discloses a method in which an additive such as a colorant is added to a radical monomer to carry out polymerization. A process is described for obtaining colorant-containing polymer particles.

[0004] In the case of the emulsion polymerization method, for example, JP-A-1-093749
In JP-A No. 195, there is described a method of embedding or fixing a colorant to particles formed by an emulsion polymerization method by mechanical impact or compressive force.

[0005]

However, in the above prior art, the colored polymer particles produced by the suspension polymerization method have a particle size limited to a range of 1 to 100 μm, and it is difficult to produce particles having a particle size smaller than the particle size. It is. In addition, in the emulsion polymerization method, since the colorant is exposed on the surface, storage stability and the like are poor.

The colored polymer particles of the present invention have a fine particle size because they are formed by an emulsion polymerization method, and are monodispersed in distribution. Therefore, a carrier for an electrophotographic toner, a carrier for an immunological diagnostic reagent, and a gap adjustment for a liquid crystal display panel. It can be used as an agent, standard particles for particle size measurement, a filler for chromatography, a filler for cosmetics, a texture modifier for synthetic leather, etc., and has a wide range of uses.

[0007]

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

[0008]

In order to achieve the above object, the colored polymer particles of the present invention use a colorant treated with a surface treating agent, preferably dispersed in water, Emulsion polymerization was carried out in the presence of a saturated monomer and a water-soluble radical polymerization initiator, whereby polymer particles containing a colorant could be obtained. In the production method,
The concentration of the surface treatment agent is preferably 0.01 to 20% by weight based on the colorant. Further, the colored polymer particles are useful as a toner for electrophotography and a carrier for immunoassay.

Hereinafter, the present invention will be described specifically.

[Colored polymer particles] The colored polymer particles of the present invention are polymer particles obtained by polymerizing a polymerizable monomer, and a colorant having been subjected to a surface treatment in the polymer particles. It was included.

[Dispersant] The concentration of the dispersant in the present invention is such that when the colorant is dispersed in the aqueous phase, the colorant can be easily dispersed. Except for growth, the concentration is below the concentration at which no new particles are 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. I have. In addition, at the time of polymerization, the concentration of the surfactant below the CMC or the surfactant desorbed from the particle surface during the polymerization process is lower than the CMC.
Indicates that the concentration does not exceed. This is because, when the desorbed surfactant forms micelles at CMC or higher, unreacted monomers in the polymerization process cause emulsion polymerization in the micelles to promote the formation of new particles, and the polymer containing no colorant This is because particles are generated.

As a dispersant, water-soluble polymers (gelatin,
Tragacanth gum, starch, methylcellulose, hydroxyethylcellulose, carboxymethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylate, etc., and poorly soluble fine powdered inorganic compounds (barium sulfate, calcium sulfate, barium carbonate, calcium carbonate, magnesium carbonate, Calcium phosphate, talc, bentonite, diatomaceous earth, clay, etc.).

Also, a sulfonate of a surfactant (sodium dodecylbenzenesulfonate, sodium arylalkyl polyethersulfonate, 3,3-disulfonediphenylurea-4,4-diazo-bis-amino-8-naphthol-6) is used. -
Sodium sulfonate, ortho-carboxybenzene-azo-dimethianiline, sodium 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-6-sulfonate), sulfuric acid Ester salts (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 stearate, etc.) No.

[Monomer] As the polymerizable monomer, a conventionally known monomer can be used, and a radical polymerizable monomer is particularly preferable. One or more of them can be used in combination to satisfy the required characteristics.

Specifically, a monovinyl aromatic monomer,
(Meth) acrylic ester monomer, vinyl ester monomer, vinyl ether monomer, monoolefin monomer, diolefin monomer, halogenated olefin monomer, polyvinyl monomer A body or the like can be used.

Examples of the vinyl aromatic monomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, and 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-
Styrene-based monomers such as dichlorostyrene and derivatives thereof may be mentioned.

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-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.

The olefin monomers include ethylene,
Propylene, isobutylene, 1-butene, 1-pentene, 4-
Monoolefin monomers such as methyl-1-pentene, and diolefin monomers such as butadiene, isoprene, and chloroprene are exemplified.

Further, a crosslinking monomer may be added to improve the properties 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 kinds according to 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 as long as 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) salts, etc.), Oxide compounds and the like.

Further, the above radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. By using a redox-based initiator, the polymerization activity is increased, the polymerization temperature can be reduced, and a further reduction in the polymerization time can be expected.

As the polymerization temperature, any temperature may be selected as long as it is higher than 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 by using a combination of a polymerization initiator started at room temperature, for example, a hydrogen peroxide-reducing agent (such as ascorbic acid).

[Colorant] As the colorant, conventionally known colorants can be used. Any colorant can be used, but specifically, inorganic or organic pigments are preferably used.

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

As pigments 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 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.

The pigments for green or cyan include:
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 may be used alone or in combination of two or more as required to adjust the color to the desired one. The amount of the pigment added is about 2 to about 20 with respect 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 ones can be used. Specifically, a silane compound, a titanium compound, or the like can be preferably used.

Examples of the silane compound include alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, and diphenyldimethoxysilane; silizane such as hexamethyldisilozane; γ-chloropropyltrimethoxysilane; vinyltrichlorosilane , Vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane,
γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, and the like.

As the titanium compound, for example, TTS, 9S, 38S, 41B, 46B, 55, 138S, 238S, which are commercially available under the trade name "Plenact" manufactured by Ajinomoto Co., Inc.
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
TAB, TTOP and the like can be mentioned.

[Method for Producing Colored Polymer Particles] The method for producing colored polymer particles of the present invention comprises dispersing a colorant treated with a surface treating agent and dissolving a water-soluble radical polymerization initiator in an aqueous phase. This is a method for obtaining colored polymer particles by dropping an ethylenically unsaturated monomer and performing emulsion polymerization, wherein the colorant is contained in the polymer particles.

The colored polymer particles of the present invention produced as described above are electrophotographic toners, carriers for immunological diagnostic reagents, gap adjusting agents for liquid crystal display panels, standard particles for particle size measurement, packing for chromatography. Agent, cosmetic filler, synthetic leather texture modifier, and the like.

Electrophotographic toner: When used in an electrophotographic toner, it is useful not only as a resin for a pulverized toner but also as a polymerized toner.

When the colored polymer particles of the present invention are used as an electrophotographic toner, it is necessary to contain components to be added to the polymer as a toner. As the above components,
Examples include a charge control agent and a fixing improver. These components can be introduced by adding a desired content to the polymerizable monomer.

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

[Fixing Improving Agent] Known fixing improving agents 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, and the like are used.

[Charge Control Agent] As the charge control agent, those known in the art can be used. However, when a monomer having a polar group on the polymer particle surface is copolymerized, it may not be necessary in some cases. As used herein, the polar group refers to a carboxyl group, a sulfonic acid group, an amino group, an ammonium base, or the like, which has a positive or negative charge.

Examples of the charge controlling agent include a positively chargeable 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, and a fluorine treatment. Examples include an activator and the like, an organic complex having an electron accepting property as a negative charge, chlorinated paraffin, chlorinated polyester, sulfonylamine of copper phthalocyanine, and the like.

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

Carrier for Immunological Diagnostics: The polymerized colored particles of the present invention are useful as a carrier for immunological diagnostics due to their properties such as uniform particle size and the fact that the particle surface is not contaminated by contaminants. Used.

As a carrier for immunological diagnosis, it is necessary to immobilize an immunologically active substance, for example, an antigen, an antibody or a receptor on the particle surface. For immobilization of an immunologically active substance, a physical adsorption method and a chemical immobilization method are known. The former is a method of physically adsorbing and immobilizing on a hydrophobic surface, for example, by using polymer particles using styrene and its derivatives, acrylates, methacrylates, etc., easily and immunologically. Active sites such as (Fa
b) 'can be immobilized in a form that does not adsorb. 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 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 or a thiol group are used.
Using a known bifunctional reagent, an immunologically active substance can be reacted and immobilized by covalent bonding.

At this time, the polymerizable monomer having a functional group may be added as a copolymer monomer during polymerization. The amount of the monomer having a functional group can be appropriately determined as needed, and it is preferable to select, for example, from a range of about 0.1% to 15%.

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

[0050]

Next, the present invention will be described in detail with reference to examples.

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

[Preparation of Pigment Dispersion] After mixing 1.78 g of pigment with 0.35 g of sodium dodecylbenzenesulfonate and 50 ml of degassed ion-exchanged water, a pigment dispersion was prepared using an ultrasonic dispersing apparatus. Table 1 shows the results.

[0053]

[Table 1]

[Synthesis of Colored Polymer Particles] A temperature sensor, a nitrogen inlet tube,
A polymerization reactor equipped with a stirrer (with a disk turbine type stirring blade) was prepared. The pigment dispersion dispersed in the above formulation, 250 ml of degassed ion-exchanged water, and 5 g of potassium peroxylate were added, and 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 0.7 ml / mi in a separating funnel.
The polymerization was started by adding at the rate of n. The polymerization was completed for 7 hours. The generated particles are analyzed by a laser diffraction particle size analyzer 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 produce fine particles having very high monodispersity.

Example 2 The colored polymer particles CL-001 to 004 prepared in Example 1 were agglomerated according to the description in JP-A-60-220358, then dried and pulverized to obtain an average particle size. The diameter was 5 μm.
This was designated as CLT-001 to 004. The toner is added and mixed at a ratio of 2% by weight of silica and 1% by weight of titanium oxide to the toner,
5 parts of this externally added toner and 95 parts of ferrite particles (carrier) surface-coated with a methyl methacrylate / styrene copolymer were mixed to prepare a developer.

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

An electrophotographic copier "U-Bix" using the above developer and equipped with a heat roller fixing device and a cleaning blade.
3032 "(manufactured by Konica Corporation), a real image 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 the determination was made based on the number of identifiable thin lines per 1 mm.

(2) Fog A continuous copy image is formed in a normal temperature and normal humidity environment (temperature: 20 ° C., relative humidity: 60%), and a “Sakura Densitometer PDA-6” is formed.
The reflection density of each color in a white background portion was measured by "0" (manufactured by Konica Corporation), and the fog was determined based on 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 contamination due to hot offset occurs is measured. Was.

(4) Degree of Coloring of Toner A single layer of toner is adhered to a white label, and this toner layer is referred to as “Sakura Densitometer PDA-60” (Konica Corporation)
The reflection density of each color was measured using
3 or more was evaluated as 、, and 1.3 or less as ×.

(5) Cleaning Property The surface of the photoreceptor was visually observed and evaluated by the number of copies at the time when 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. The particle size distribution was measured over time in an actual test, and the number% of toner having a volume average diameter of 1/3 or less at the start, at the time of fogging, and at 50,000 copies was shown. The measurement was performed using a laser diffraction particle size analyzer SALD-1100 (manufactured by Shimadzu). The results are shown in Table 3.

[0066]

[Table 3]

As is clear from Table 3, the toner using the colored polymer particles of the present invention not only has sufficiently comparable performance to the kneading and pulverizing toner, but also has a particle size distribution determined by a real test. It can be seen that the toner is a good toner with little change. In particular, the number% of toner having a volume average diameter of 1/3 or less
When it exceeds 10%, it is known that the chargeability of the toner is hindered. This also indicates that the colored polymer particles of the present invention are more stable than the comparative toner.

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

An anti-α-fetoprotein antibody (IgG fraction) was added to this dispersion, and 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
Was diluted with PBS (pH = 7.2) to give an immunodiagnostic reagent for AFP. Using purified human α-fetoprotein (manufactured by Dako) as a mother liquor at 1000 ng / ml, a dilution series of 1,000, 500, 25
0, 125, 62.5, 31.25, 15.63, 7.81 ng / ml were prepared.

25 μl of each AFP solution was added to latex reagent 25
The aliquots were collected, mixed in a microplate, allowed to stand for 1 hour, and the aggregation image was observed. The target cellodia AFPmo
The same test solution was measured using no (manufactured by Fujirebio) in accordance with a conventional method. The results are shown in Table 4 below.

[0072]

[Table 4]

[0073]

According to the present invention, monodispersed colored polymer particles having a small particle size can be easily formed with good reproducibility. Moreover, the colored polymer particles have excellent performance as an electrophotographic toner and an immunoassay carrier.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-108554 (JP, A) JP-A-63-271467 (JP, A) JP-A-62-181302 (JP, A) JP-A 61-181 167955 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 2/00-2/60

Claims (7)

(57) [Claims] (1)Silane compoundSurface treatment agentUsed as
ProcessedExcluding magnetic powderColorantDispersed in water, water soluble
Ethylenically unsaturated monomer is produced using radical polymerization initiator.
Emulsion polymerizationOf colored polymer particles to obtain colored polymer particles
A method for producing a colored polymer containing the coloring agent
Get particlesProduction of colored polymer particles characterized by the following:One
Law. 2. Use of a titanium compound as a surface treatment agent
Disperse colorants except treated magnetic powder in water,
Ethylenically unsaturated monomer is produced using radical polymerization initiator.
Emulsion polymerization to obtain colored polymer particles
A method for producing a colored polymer containing the coloring agent
Method for producing colored polymer particles characterized by obtaining particles
Law. 3. The concentration of the surface treatment agent is set at 0.
Producing how the colored polymer particles according to claim 1 or 2, wherein the treatment with a concentration of 01~20wt%. 4. Use of a silane compound as a surface treatment agent
Disperse colorants except treated magnetic powder in water,
Ethylenically unsaturated monomer is produced using radical polymerization initiator.
Colored polymer particles obtained by emulsion polymerization,
That the color polymer particles contain the colorant.
Characterized colored polymer particles. 5. Use of a titanium compound as a surface treatment agent
Disperse colorants except treated magnetic powder in water,
Ethylenically unsaturated monomer is produced using radical polymerization initiator.
Colored polymer particles obtained by emulsion polymerization,
That the color polymer particles contain the colorant.
Characterized colored polymer particles. 6. An electrophotographic toner, which is obtained from the colored polymer particles according to claim 4. Description: 7. A carrier for immunoassay, which is obtained from the colored polymer particles according to claim 4. Description: