JP2997092B2 - Colored spherical fine particles, production method thereof and use thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to colored spherical fine particles, a method for producing the same, and uses thereof. More specifically, a carbon black polymer obtained by reacting a polymer capable of reacting with the carbon black to the carbon black is localized on the particle surface side portion, has excellent blackness, and has various resins or binders. Good affinity, colorant such as thermoplastic resin composition, coating composition, ink ribbon coating agent for thermal transfer, ink for thermal transfer, curable resin composition, back coating agent for magnetic recording media, matting agent TECHNICAL FIELD The present invention relates to colored spherical fine particles which can be used as a charge control agent, a method for producing the same, and uses thereof.

[0002]

2. Description of the Related Art Colorants such as thermoplastic resin compositions, coating compositions, thermal transfer ink ribbon coating agents, thermal transfer inks, curable resin compositions, back coating agents for magnetic recording media, matting agents, When carbon black is added as a charge control agent or the like, coagulation force between particles of carbon black is too strong, and carbon black lacks affinity with a resin, etc., and is mixed or dispersed uniformly under ordinary mixing or dispersion conditions. It is extremely difficult to achieve the desired performance.

In order to solve such problems, a method using a specific resin as a dispersant, a method using a grafted carbon black obtained by polymerizing a polymerizable monomer in the presence of a specific carbon black, Various methods have been proposed, such as a method using a surface-treated grafted carbon black obtained by grafting a polymer onto the surface of carbon black.

[0004]

However, in the former method, although the dispersibility of the carbon black in the resin is slightly improved, the improvement is not sufficiently improved, and the latter method is not improved. Despite the complexity and high cost of the process for producing black, the grafting efficiency was low and the surface treatment efficiency was extremely poor, so the effect of improving dispersibility was not sufficient, and it was better. There has been a demand for a method for improving the dispersibility of carbon black.

[0005] Further, further improvement in blackness of the composition has been demanded. Therefore, the object of the present invention is to
An object of the present invention is to provide a novel colored spherical fine particle satisfying these demands, a method for producing the same, and a use thereof. That is,
An object of the present invention is that a carbon black graft polymer is localized on a particle surface side portion, has excellent blackness, has good affinity with various resins or binders, and has a thermoplastic resin composition and a coating composition. Novel colored spherical fine particles that can be used as a colorant such as a thermal transfer ink ribbon coating agent, a thermal transfer ink, a curable resin composition, a back coating agent for a magnetic recording medium, a matting agent, a charge control agent, etc. It is to provide a manufacturing method and its use.

[0006]

SUMMARY OF THE INVENTION The objects of the present invention are to provide a monomer component capable of polymerizing a carbon black graft polymer obtained by reacting carbon black with a polymer capable of reacting with the carbon black. Monomer component), and then a carbon black graft polymer obtained by polymerizing the polymerizable monomer component is localized on the particle surface side, has excellent blackness, and can be used with various resins or binders. Is achieved by the colored spherical fine particles having good affinity.

[0007] Further, these objects are aimed at converting carbon black and a polymer which can react with the carbon black into a polymer.
The carbon black graft polymer obtained in this manner is dispersed in a polymerizable monomer component, and then the polymerizable monomer component is polymerized. This is achieved by a method for producing colored spherical fine particles, characterized in that the polymer is localized near the particle surface, is excellent in blackness, and has good affinity with various resins or binders.

The colored spherical fine particles may be used in combination with various resin binders, solvents and the like to form a thermoplastic resin composition, a coating composition, a thermal transfer ink ribbon coating agent, a thermal transfer ink, a curable resin composition, and a magnetic recording medium. It is used in a wide range of applications as a coloring agent such as a back coating agent for media, a matting agent, an antistatic agent and the like, and exhibits excellent performance.

[0009]

In the colored spherical fine particles according to the present invention, since carbon black is supported on spherical fine particles made of a polymer, the affinity for the binder and the matrix resin when the carbon black is dispersed in the binder and the matrix resin is used. Excellent. As a method of supporting carbon black on the surface of a spherical particle made of a polymer in a colored spherical particle, a physical (mechanical, thermal) energy mainly containing an impact force in a state in which the surface of the spherical particle is coated with carbon black. There is a dry treatment method of pressing carbon black to spherical fine particles by giving
This method has the disadvantages of high cost due to the need for special equipment, and the fixing of carbon black is not sufficient because the carbon black is simply fixed by pressure bonding. Has a serious drawback that it is easily dropped off. On the other hand, in the colored spherical fine particles according to the present invention, the carbon black is not used as it is, but is reacted with a polymer and used in the form of a carbon black graft polymer. It is made to localize in the part. That is, in the present invention, carbon black is incorporated into spherical fine particles, and a polymer is bonded to carbon black, and the affinity of the bonded polymer for spherical fine particles (which is also a polymer) is utilized. The carbon black is also fixed to the spherical fine particles. Therefore, the fixation of the carbon black to the spherical fine particles is strengthened, and the carbon black is unlikely to fall off from the spherical fine particles. Further, since the carbon black is localized on the surface side of the spherical fine particles, the blackness is extremely excellent.

In the present invention, in order to obtain a carbon black graft polymer, the reactivity of a functional group (for example, —OH, —COOH,> C ＝ O, etc.) on the surface of carbon black is used. As the polymer that can react with carbon black, any polymer having a reactive group that can easily react with a functional group present on the surface of carbon black can be used without particular limitation. As a reactive group that can easily react with a functional group present on the surface of carbon black,
Examples include an aziridine group, an oxazoline group, an N-hydroxyalkylamide group, an epoxy group, a thioepoxy group, an isocyanate group, a vinyl group, a silicon-based hydrolyzable group, and an amino group. One type of group.

Examples of the polymer having reactivity with carbon black as described above include vinyl polymers, polyesters, and polyethers having at least one reactive group in the molecule. The molecular weight of the polymer is not particularly limited, but the number average molecular weight is 500 to 1,000, in view of a remarkable treatment effect on carbon black and workability at the time of reaction with carbon black.
000, more preferably
1,000-500,000, most preferably 2,000
The range is from 0 to 100,000. The reactive group must have at least one reactive group per molecule on average, but the larger the amount of the reactive group, the worse the dispersibility of the carbon black graft polymer in other substances. Therefore, it is preferable that the average is 1 to 5, more preferably 1 to 2 and most preferably 1 in one molecule.

In order to obtain such a polymer having reactivity with carbon black, for example, the above-mentioned polymer monomer having a reactive group in the molecule is optionally used in combination with other polymerizable monomers. A method of polymerizing according to a procedure, a method of reacting a compound having the reactive group in the molecule with a polymer having a group capable of reacting with the compound, and the like can be appropriately adopted. In the present invention, one or more selected from an aziridine group, an oxazoline group, an N-hydroxyalkylamide group, an epoxy group, a thioepoxy group, and an isocyanate group, particularly in terms of reactivity with a functional group present on the surface of carbon black. It is preferable to use a polymer having two or more types as reactive groups, more preferably one or two selected from an aziridine group, an oxazoline group, and an epoxy group.
A polymer having at least one species as a reactive group, most preferably a polymer having at least one reactive group selected from the group consisting of an aziridine group and an oxazoline group. Further, it is preferable to use a vinyl polymer having a reactive group in consideration of the affinity when the carbon black graft polymer is dispersed in the polymerizable monomer component used for suspension polymerization.

The method for obtaining a polymer having reactivity with carbon black includes, for example, (1) polymerizing the above-mentioned polymerizable monomer having a reactive group in a molecule together with another polymerizable monomer if necessary. And (2) a method of reacting a compound having a reactive group in the molecule with a polymer capable of reacting with the compound to introduce the reactive group into the polymer.

The polymerizable monomer having a reactive group in the molecule (hereinafter referred to as monomer (a)) includes, for example, an aziridine group-containing polymerizable monomer described in International Publication No. WO88 / 03545. , An oxazoline group-containing polymerizable monomer,
N-hydroxyalkylamide group-containing polymerizable monomers, epoxy group-containing polymerizable monomers, thioepoxy group-containing polymerizable monomers, and isocyanate group-containing polymerizable monomers. More than one species can be used.

The monomer which can be used together with these monomers as required (hereinafter referred to as monomer (b)) is not particularly limited as long as it can be copolymerized with monomer (a). For example, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene,
p-methoxystyrene, p-tert-butylstyrene, p-phenylstyrene, o-chlorostyrene, m-
Styrene monomers such as chlorostyrene and p-chlorostyrene; acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate;
Dodecyl acrylate, stearyl acrylate, 2-ethylhexyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, doticyl methacrylate, methacryl Acrylic acid or methacrylic acid monomers such as 2-ethylhexyl acid, stearyl methacrylate; ethylene, propylene, butylene, vinyl chloride, vinyl acetate;
Acrylonitrile, acrylamide, methacrylamide, N-vinylpyrrolidone and the like can be mentioned, and one or more of these are used.

As the compound having a reactive group used in the method (2), (a) one kind of the reactive group is contained in the molecule.
And (b) a compound having two or more reactive groups in the molecule, (c) a compound having one or more reactive groups and a group other than the reactive group in the molecule, and the like. .
Examples of the polymer used in the method (2) include a vinyl-based polymer having a vinyl group having a group capable of reacting with the reactive compound, a polyester, and a polyether. Examples of the group capable of reacting with the compound include a hydroxyl group, a carboxyl group, an amino group, an epoxy group and the like, and a polymer having these groups can be easily obtained by known polymerization procedures such as radical polymerization and polycondensation. Can be obtained. In order to obtain a polymer having a reactive group by the method (2), the compound and the polymer may be reacted under the condition that at least one of the reactive groups remains unreacted.

When reacting carbon black with a polymer having reactivity with carbon black, even if substances such as polymer components other than the polymer, polymerizable monomers, and organic solvents are present in the reaction system. Good. Specific examples of reacting carbon black with a polymer having reactivity with the carbon black include, for example, a polymer 1 having a reactivity with carbon black with respect to 100 parts by weight of carbon black.
To 3,000 parts by weight, preferably 5 to 1,000 parts by weight, and a polymer having no reactivity with carbon black.
1,000 parts by weight, 0 to 200 parts by weight of the polymerizable monomer, and 0 to 1,000 parts by weight of the organic solvent are stirred and mixed at a temperature of 20 to 350 ° C, preferably 50 to 300 ° C. In this reaction, the reactive group in the reactive polymer is an important factor, and when the reactive group is an isocyanate group, the water contained in the carbon black hinders the progress of the reaction, so that dehydration is performed in advance. When the reactive group is an epoxy group, the reactivity becomes low when the pH of the carbon black is high, so that the pH is 8 or less, preferably 6 or less as usable carbon black. You have to choose one. When the reactive group is an aziridine group or an oxazoline group, it is most preferable because a wider range of carbon black can be selected and pretreatment such as heating is not required.
In addition, the test method of the pH of carbon black is based on Japanese Industrial Standard (JIS) K6221.

In the present invention, the carbon black graft polymer is localized on the surface side of the particles and has excellent blackness,
Colored spherical fine particles having good affinity with various resins or binders are dispersed in the polymerizable monomer of the carbon black graft polymer obtained by the above method, and then the polymerizable monomer is obtained by a known procedure. It is obtained by polymerization. As an example of a polymerizable monomer, when producing a polymer having reactivity with carbon black as described above, other polymerizable monomers used as necessary together with a polymerizable monomer having a reactive group in the molecule There is.

In the present invention, the solubility parameter (SP) value of a polymer capable of reacting with carbon black is determined from the solubility parameter value obtained when the monomer component dispersing the carbon black graft polymer becomes a polymer. Is dispersed in a large monomer component, and thereafter, the polymerizable monomer is polymerized by a known procedure, whereby the carbon black graft polymer is localized near the particle surface, has excellent blackness, and has various resins. Alternatively, colored spherical fine particles having good affinity for the binder can be obtained.

In the present invention, even when the solubility parameter of the polymer capable of reacting with carbon black is smaller than the solubility parameter when the monomer component dispersing the carbon black graft polymer becomes a polymer. The solubility parameter value of the carbon black graft polymer is dispersed in a monomer component larger than the solubility parameter value of the monomer component in which the carbon black graft polymer is dispersed, and then the polymerizable monomer is dispersed. By rapidly polymerizing by a known procedure, the carbon black polymer is localized at the particle surface side portion, is excellent in blackness, and can obtain colored spherical fine particles having good affinity with various resins or binders. is there.
As a method of rapidly polymerizing the polymerizable monomer in which the carbon black graft polymer is dispersed, a known method can be used. For example, the polymerization temperature may be increased, and the amount of the polymerization initiator may be increased.

In the present invention, the solubility parameter value of the polymer capable of reacting with carbon black and the solubility parameter value when the monomer component dispersing the carbon black graft polymer becomes a polymer are the same or different. When the value is close, localization of the carbon black graft polymer to the target particle surface side becomes difficult, and the carbon black graft polymer is uniformly dispersed inside the particles, resulting in colored spherical fine particles having poor blackness. .

The polymerizable monomer component may contain at least 0.005% by weight of a crosslinkable compound. The content of the crosslinkable compound is preferably 0.01 to 80% by weight, more preferably 0.05 to 50% by weight.
As such a crosslinking agent, International Publication No. WO88 / 0
3545, and one or more of them can be used.

When polymerizing the polymerizable monomer, another polymerizable material such as a polyester may be present in the monomer. Known additives such as a chain transfer agent for adjusting the degree may be appropriately blended. In the colored spherical fine particles according to the present invention, the blending amount of the carbon black graft polymer with respect to the polymer constituting the spherical fine particles is not particularly limited, but is preferably 1 to 100% by weight.

In the colored spherical fine particles according to the present invention, the carbon black graft polymer is located on the surface side of the spherical fine particles, that is, in the portion from the particle surface to R / 2 with respect to the radius (R) of the spherical fine particles. It is necessary that 70% by weight or more of the entire carbon black graft polymer be localized, and it is preferable that R / 4
Up to 70% by weight of the entire carbon black graft polymer is localized.

The colored spherical fine particles according to the present invention are:
A particle size of 0.1 to 100 microns is preferred because it is easy to handle and, when used for various purposes, its effect is remarkably exhibited. Further, it is preferable to carry out the polymerization of the monomer component by suspension polymerization, since the colored spherical fine particles having the above-mentioned particle diameter can be obtained as they are at the same time as the polymerization. In the suspension polymerization, it is preferable to carry out the reaction after regulating the particle diameter or while regulating the particle diameter. In particular, it is preferable to carry out the reaction after regulating the particle diameter. The regulation of the particle size is, for example, as follows: a suspension in which a predetermined component is dispersed in an aqueous medium is subjected to T.V. K. Stirring is performed with a homomixer. Alternatively, it is carried out by passing once or several times through a high-speed stirrer such as a line mixer (for example, Ebara Milder).

As the stabilizer used in the suspension polymerization, polyvinyl alcohol, starch, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose,
Water-soluble polymers such as sodium polyacrylate and sodium polymethacrylate; surfactants such as anionic surfactants, cationic surfactants, zwitterionic surfactants, and nonionic surfactants; and other sulfuric acids barium,
Calcium sulfate, barium carbonate, magnesium carbonate, calcium phosphate, talc, clay, diatomaceous earth, metal oxide powder and the like are used.

Examples of the anionic surfactant include fatty acid salts such as sodium oleate and castor oil, alkyl sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate, alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, and alkylnaphthalene. Sulfonate, alkane sulfonate, dialkyl sulfosuccinate, alkyl phosphate ester, naphthalene sulfonic acid formalin condensate, polyoxyethylene alkyl phenyl ether sulfate, polyoxyethylene alkyl sulfate, and the like.

Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxysorbitan fatty acid ester, polyoxyethylene alkylamine; glycerin fatty acid ester, Oxyethylene-oxypropylene block polymer and the like.

Examples of the cationic surfactant include alkylamine salts such as laurylamine acetate and stearylamine acetate, and quaternary ammonium salts such as lauryltrimethylammonium chloride. Examples of the amphoteric surfactant include lauryl dimethylamine oxide.

These stabilizers should be used by appropriately adjusting the composition and the use amount thereof in accordance with the desired particle diameter of the obtained colored spherical fine particles. For example, as a stabilizer,
When a water-soluble polymer is used, it is preferably 0.01 to 20% by weight, preferably 0.1 to 10% by weight, based on the polymerizable monomer component. In the case of a surfactant, it is suitably from 0.01 to 10% by weight, preferably from 0.1 to 5% by weight, based on the polymerizable monomer component.

As the polymerization initiator used in the polymerization, oil-soluble peroxide-based or azo-based initiators which are generally used and described in International Publication No. WO88 / 03545 can be used. The polymerization initiator is used in an amount of 0.0
It is preferred to use 1 to 20% by weight, especially 0.1 to 10% by weight. The thus obtained colored spherical fine particles of the present invention have a spherical shape in which the particle diameter and the particle diameter distribution can be arbitrarily controlled, and the carbon black graft polymer as a coloring component is localized near the particle surface.

The colored spherical fine particles can be used as a coloring agent for thermoplastic resins and thermosetting resins used in the production of resin compositions such as masterbatches and molding materials. As the thermoplastic resin, saturated polyester resin, for example, polyethylene naphthalate, polybutylene terephthalate, etc., acrylic resin, for example, methyl methacrylate resin, polycarbonate, polyimide, vinyl chloride polymer, styrene polymer, polyamide, polyolefin, butyral resin, polyurethane, Examples include polyethylene, polypropylene, acrylonitrile / butadiene / styrene copolymer, and styrene / acrylonitrile copolymer.

The thermosetting resin is represented by an unsaturated polyester resin obtained by dissolving an unsaturated polyester in a polymerizable monomer represented by styrene, an epoxy resin, a diallyl phthalate resin, a phenol resin and a melamine resin. There are amino resin, polyimide resin, polyurethane resin and the like. The mixing ratio of the colored spherical fine particles to the thermoplastic or thermosetting resin is not particularly limited, but is usually 5 to 70% by weight, preferably 10 to 40% by weight. That is, if the content is less than 5% by weight, it is difficult to obtain a thermoplastic or thermosetting resin composition having excellent coloring properties, conductivity, heat resistance, abrasion resistance, low shrinkage, and the like. This is not preferred because the properties of the resin composition are impaired.

Another application of the colored spherical fine particles is a coating composition. The binder used in the coating composition is a thermoplastic resin, a thermosetting resin or a reactive resin capable of forming a film by coating on various substrates, and one or a mixture of two or more thereof depending on the application. Is used. The average molecular weight of the thermoplastic resin is 1,000 to 1
About 100,000 resins are preferably used, and specific examples thereof include vinyl chloride resins such as vinyl chloride polymers and vinyl chloride / vinylidene chloride copolymers; vinyl acetate polymers and vinyl acetate / ethylene copolymers. , Vinyl ester resins such as vinyl acetate / methyl methacrylate copolymer;
(Meth) acrylic acid ester (co) polymer, (meth) acrylic acid ester resin copolymer such as (meth) acrylic acid ester / acrylonitrile copolymer, (meth) acrylic acid ester / styrene copolymer, styrene・ Styrene resins such as butadiene / acrylonitrile copolymer; Polyamide resins such as poly (ε-caprolactam); condensates of adipic acid and hexamethylenediamine; condensates of terephthalic acid and ethylene glycol; adipic acid and ethylene Polyester resins such as condensates with glycols; polyolefin resins such as polyethylene, chlorinated polypropylene, carboxyl-modified polyethylene, polyisobutylene and polybutadiene; cellulose derivatives such as cellulose acetate, cellulose propionate and nitrocellulose; Butyral resin and the like. As these resins, commercially available products may be used as they are, or resins synthesized by ordinary known methods can be used.

The thermosetting resin or the reactive resin can form a crosslinked structure caused by an addition reaction, a condensation reaction, or the like by heating, irradiating with active energy rays, drying or other means during or after the film formation. For example, novolak resins; phenolic resins such as resol resins; amino resins such as urea resins, melamine resins, benzoguanamine resins; various alkyd resins; unsaturated polyester resins; curable acrylic resins; Examples thereof include urethane-modified resins such as a polyester group containing a nate group and a polyether containing a isocyanate group; polyamine resins; and epoxy resins.

The binder should be selected according to the adhesion and wettability to the substrate to be coated, the hardness, flexibility, chemical resistance, stain resistance, weather resistance, etc., required of the coating. , Alone or 2 in consideration of the purpose of use of the coating composition.
A combination of more than one species is used. The coating composition containing colored spherical fine particles of the present invention can be obtained by a method of dispersing the colored spherical fine particles in various binders. The use ratio of the binder and the colored spherical fine particles in the coating composition,
Although not particularly limited, 5-300 parts by weight, preferably 10-200 parts by weight with respect to 100 parts by weight of the binder, in order to sufficiently express the properties of the coating composition and not to impair the performance as a film. Is colored.

The carbon black-containing coating composition of the present invention may optionally contain, in addition to the components described above, well-known additives to the coating composition so far as the effects are not impaired. Examples of such additives include metal soaps, dispersing aids such as surfactants, film forming aids, antistatic agents, defoamers, silica, talc, calcium carbonate, and inorganic pigments such as titanium oxide. No.

The thermal transfer ink of the present invention is obtained by dispersing the colored spherical fine particles in a binder component.
The binder component of the thermal transfer ink is a known natural or synthetic wax such as carnauba wax, montan wax, paraffin wax, microcrystalline wax, oxidized wax, low molecular weight polyethylene wax, low molecular weight polypropylene wax; polysulfone ether, polycarbonate, polystyrene , Silicone resin,
A synthetic resin such as an acrylic resin may be used. Examples of the dispersion method include a method of simply kneading the colored spherical fine particles and the binder component and a method of mixing these two components in an appropriate organic solvent. These methods allow the colored spherical fine particles to be extremely well dispersed in the binder component. The resulting thermal transfer ink is obtained. The amount of the colored spherical fine particles in the thermal transfer ink is not particularly limited, but is usually 5 to 80% by weight, preferably 20 to 60% by weight. In addition to the above components,
If necessary, known additives may be added.

The thermal transfer ink of the present invention is applied to a support represented by a PET film, a polyimide film, a capacitor paper, a silk fabric, an aluminum foil or the like by a known method such as a hot melt coater, a reverse roll coater, and a gravure roll coater. Thus, a thermal transfer ink sheet having excellent quality can be obtained. As an application of the colored spherical fine particles, there is an ink ribbon coating agent for thermal transfer. Examples of the binder component of the ribbon coating agent include known vinyl chloride polymers, vinyl chloride-vinyl acetate copolymers, acrylic resins, styrene polymers, polyurethane resins, polyester resins, and the like. Add colored spherical fine particles to these binder components, stir and mix well,
Obtain a ribbon coating agent. The compounding amount of the colored spherical fine particles with respect to the coating agent is 1 to 40% by weight, preferably 5 to 20% by weight. The ribbon coating agent thus obtained can be applied to a substrate using a known means such as a roll coater, an air knife coater, an air doctor coater, and a spray coater, and a ribbon coat layer can be formed on the back surface.

The application of the colored spherical fine particles is a back coating agent for a magnetic recording medium. As a binder component of the back coat agent, for example, known vinyl chloride resins, vinyl chloride / vinyl acetate copolymer resins, acrylic resins, styrene resins, polyurethane resins, polyester resins, and the like are used. Colored spherical fine particles are added to these binder components and mixed well with stirring to form a back coat agent. The amount of the colored spherical fine particles to be added to the coating agent is not particularly limited, but is usually in the range of 1 to 40% by weight, preferably 5 to 20% by weight. The back coat agent thus obtained can be applied to a substrate using a known means such as a roll coater, an air knife coater, an air doctor coater, and a spray coater, and a back coat layer can be formed on the back surface.

As the substrate used for the magnetic recording medium of the present invention, known films, sheets and tapes of polyester, cellulose acetate, polyvinyl chloride and the like are used, and the magnetic recording layer is a coating agent containing a known magnetic powder. Can be formed by a method of applying a magnetic material or a method of evaporating a magnetic material.

[0042]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to the following examples. The “parts” in the following Examples and Comparative Examples are all by weight unless otherwise specified. -Synthesis Example 1-A polyvinyl alcohol (PVA-20) was placed in a flask equipped with a stirrer, an inert gas introduction pipe, a reflux condenser, and a thermometer.
5, Kuraray Co., Ltd.) 0.1 parts of deionized water dissolved
00 parts were charged. A mixture prepared by dissolving 8 parts of benzoyl peroxide in a polymerizable monomer composed of 97 parts of styrene and 3 parts of glycidyl methacrylate previously prepared therein was added thereto, and stirred at high speed to form a uniform suspension. .
Next, the mixture was heated to 80 ° C. while blowing in nitrogen gas, and stirred at this temperature for 5 hours to carry out a polymerization reaction, followed by cooling to obtain a polymer suspension. The polymer suspension was filtered, washed, and dried to obtain a polymer having an epoxy group as a reactive group. The solubility parameter value of the polymerizable monomer styrene used here was 9.3 [cal / c
m ³ ] ^1/2 , and the solubility parameter value of polystyrene as a polymer is 9.42 [cal / cm ³ ].
^1/2 .

40 parts of a polymer having an epoxy group as a reactive group and 20 parts of carbon black MA-100R (manufactured by Mitsubishi Kasei Kogyo Co., Ltd.) were heated at 160 ° C. using a laboratory blast mill (manufactured by Toyo Seiki Co., Ltd.). The mixture was kneaded and reacted at 100 rpm, cooled, and pulverized to obtain a carbon black graft polymer (1). -Comparative Synthesis Example 1-40 parts of styrene and 20 parts of carbon black MA-100R were charged into the same flask as used in Synthesis Example 1, heated to 140 ° C while blowing nitrogen gas, and stirred at this temperature for 5 hours. After the polymerization reaction, the mixture was cooled. After the reaction, 300 parts of toluene was added to the reaction product, and 7000 parts of methanol was added to cause reprecipitation to obtain a grafted carbon black for comparison (1).

Example 1 In a flask similar to that used in Synthesis Example 1, polyoxyethylene alkylphenyl ether sulfonammonium (Hytenol N-08, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was used.
Five parts of dissolved deionized water 900 parts were charged. A carbon black graft polymer (1) 15 as a colorant obtained in Synthesis Example 1 was added to a polymerizable monomer component prepared in advance, comprising 76 parts of methyl methacrylate and 9 parts of trimethylolpropane trimethacrylate. And a mixture of 1 part of azobisisobutyronitrile was charged. K. The mixture was stirred with a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) at 8,000 rpm for 5 minutes to obtain a uniform suspension. Then heat to 75 ° C while blowing in nitrogen gas,
Stirring was continued at this temperature for 5 hours to carry out a suspension polymerization reaction, followed by cooling. The suspension was filtered, washed, and dried to obtain colored spherical fine particles (1).

The obtained colored spherical fine particles (1) were measured with a Coulter counter (aperture: 100 μm). As a result, the average particle diameter was 3.97 μm, and the standard deviation was 1.5 μm.
m. When the powder of the colored spherical fine particles (1) was observed with an optical microscope, the powder was uniformly black and had no color unevenness. When the cross section of the particles was observed with a transmission electron microscope (TEM), the carbon black graft polymer was localized near the particle surface. The solubility parameter value of the polymerizable monomer methyl methacrylate used here was 8.8 [cal / cm ³ ] ^1/2 , and the solubility parameter value of the polymer polymethyl methacrylate was 9 0.53 [cal / cm ³ ] ^1/2 .

Example 2 The polymerizable monomer components used in Example 1 were 76 parts of butyl methacrylate and 9 parts of trimethylolpropane trimethacrylate, and the polymerization initiator was 2,2'-azobis (2,4- Colored spherical fine particles (2) were obtained by repeating the same method as in Example 1 except that 1 part of dimethylvaleronitrile), the polymerization temperature was 55 ° C., and the polymerization time was 8 hours. The properties of the obtained colored spherical fine particles (2) were examined in the same manner as in Example 1, and the results are as shown in Table 1.

The solubility parameter value of the polymerizable monomer butyl methacrylate used here was 8.2.
[Cal / cm ³ ] ^1/2 , and the solubility parameter value of the polymer polybutyl methacrylate was 8.
75 [cal / cm ³ ] ^1/2 . Comparative Example 1 In Example 1, carbon black MA-100 was used instead of 15 parts of the carbon black graft polymer (1).
When the same method as in Example 1 was repeated except that R5 part was used as it was, the dispersibility of the carbon black in the polymerizable monomer was poor, and it was difficult to regulate the particle size to a uniform particle size. Also, the dispersion stability of the suspension during the polymerization reaction was poor, and most of the non-volatile components aggregated and settled at the bottom of the flask.

Comparative Example 2 In Example 1, 15 parts of the comparative grafted carbon black (1) obtained in Comparative Synthesis Example 1 (5 parts of carbon black) was used instead of 15 parts of the carbon black graft polymer (1). Comparative Example 2) was obtained by repeating the same method as in Example 1 except that the above-mentioned Comparative Example 1 was used.

The properties of the comparative fine particles (2) were examined in the same manner as in Example 1, and the results are as shown in Table 1. -Comparative Example 3-Example 1 was repeated except that the polymerization initiator used in Example 1 was 2 parts of 2,2'-azobis (2,4-dimethylvaleronitrile), the polymerization temperature was 55 ° C, and the polymerization time was 8 hours. The same method as in Example 1 was repeated to obtain comparative colored spherical fine particles (3).

The properties of the comparative fine particles (3) were examined in the same manner as in Example 1, and the results are as shown in Table 1. Comparative Example 4 76 parts of styrene, trimethylolpropane, and trimethacrylate 9 were used as the polymerizable monomer in Example 1.
The same procedure as in Example 1 was repeated except that the above-mentioned parts were used, to obtain comparative spherical fine particles (4).

The properties of the obtained comparative fine particles (4) were examined in the same manner as in Example 1, and the results are as shown in Table 1. Comparative Example 5 Spherical fine particles containing no colorant were obtained by repeating the same method as in Example 1 except that 15 parts of the carbon black graft polymer (1) was not used. 95 parts of spherical fine particles containing no colorant and carbon black MA-1
00R5 parts were fixed using a hybridizer (manufactured by Nara Machinery Co., Ltd.) to obtain comparative colored spherical fine particles (5).

The properties of the particles of Comparative Fine Particle (5) were examined in the same manner as in Example 1, and the results are as shown in Table 1.

[0053]

[Table 1]

The annotations in Table 1 are as follows. (Note 1) Particle properties Particle diameter: Measured by a Coulter counter (manufactured by Coulter Electronics Inc .: TA-II type). Particle size distribution: The standard deviation was measured with a Coulter counter (manufactured by Coulter Electronics INS: Model TA-II). Dispersibility of carbon black: The cross section of the particles was observed using a transmission electron microscope (TEM) for the dispersion state of the carbon black in the particles.

-Example 3 and Comparative Examples 6, 7-80 parts of polyurethane as a binder (trade name: Polydur 9-1240, manufactured by Mikuni Paint Co., Ltd.), curing agent (trade name: Polydur D05-100, Mikuni Paint) The colored spherical fine particles (1) obtained in Example 1 and the comparative colored spherical fine particles (3) and (5) obtained in Comparative Examples 2 and 3 with respect to 20 parts of toluene and 200 parts of toluene.
Was added and mixed thoroughly to obtain a carbon black-containing coating composition (1) and comparative carbon black-containing coating compositions (3) and (5).

Each carbon black-containing coating composition was dried on urethane leather so that the film thickness after drying was 5 microns.
It was spray-coated, dried at room temperature, and dried at 70 ° C. for 30 minutes to obtain a coated film for a coating film performance test. Using this coating composition, blackness and matting property were evaluated. The test results are as shown in Table 2.

[0057]

[Table 2]

As is clear from Table 2, the carbon black-containing coating composition of the present invention has good dispersibility,
It turns out that it is excellent in matting property. Example 4 The colored spherical fine particles (1) obtained in Example 1 were added and mixed with 100 parts of a polyethylene terephthalate chip so that the carbon black content was 2 parts to obtain a polyester composition.

The obtained polyester composition was melt-extruded into a sheet at 290 ° C. using an extruder, and then biaxially stretched at 90 ° C. to a longitudinal stretching ratio of 3.5 times and a transverse stretching ratio of 4.0 times.
Further, the film was heat-set at 200 ° C. to obtain a film having a thickness of 15 μm. Using this film, the coarse particles and the film surface roughness were evaluated according to the evaluation methods described below, and the results in Table 3 were obtained.

Comparative Example 8 In place of the colored spherical fine particles (1) in Example 4, untreated carbon black (# 45, Mitsubishi Kasei Kogyo Co., Ltd.)
A film for comparison was obtained in the same manner as in Example 2 except that 2 parts were used as they were. The coarse particles and the film surface roughness of this comparative film were evaluated, and the results are shown in Table 3.

[Evaluation Method of Film] Coarse Particles The film is observed with a microscope under polarized transmitted light, and the presence or absence of foreign matter is examined. The number of agglomerated particles of carbon black having a maximum diameter of 5 μm or more existing in the portion where the polarized light was applied was counted, and the following judgment was made.

Special grade: less than 10 aggregated particles / 50 cm ² . Primary: 10 to 20 agglomerated particles / 50 cm ² are present. Secondary: 20 to 50 aggregated particles / 50 cm ² are present. Third grade: 50 aggregated particles / 50 cm ² or more. Note that the special grade and the first grade are put to practical use. Film surface roughness: Measured with a stylus diameter of 12.5 μ and a stylus pressure of 50 mg with a surface roughness measuring instrument manufactured by Sloan.

[0063]

[Table 3]

The film obtained in Example 3 had few coarse particles and the film surface was smooth and good. On the other hand, in the case of Comparative Example 4, since the carbon black had not been subjected to the surface treatment, it had a large amount of coarse particles and was broken when formed into a film, resulting in poor workability. -Example 5-50 parts of isophthalic acid, 70 parts of maleic anhydride, 34 parts of ethylene glycol and 38 parts of propylene glycol were subjected to an esterification reaction at 200 ° C for 22 hours in a stream of nitrogen to obtain an unsaturated polyester having an acid value of 23. . 40.4 parts of the unsaturated polyester was mixed with 50.4 parts of styrene to obtain an unsaturated polyester resin (hereinafter, referred to as unsaturated polyester resin (1)).

Next, 18 parts of the colored spherical particles (1) obtained in Example 1 were mixed with 100 parts of the unsaturated polyester resin (1), and the mixture was mixed with a thermosetting resin composition (hereinafter referred to as a resin composition). (Referred to as (1)). T-butyl peroxybenzoate 1.3 was added to the obtained resin composition (1).
Parts, zinc stearate 4 parts and calcium carbonate 100
Was added to obtain a paste. Further, 70.7 parts of 25 mm long glass fiber (diameter: 13 μm) was impregnated with an impregnating liquid obtained by mixing 1.0 part of magnesium oxide with the paste, and a sheet was formed between the two polyethylene sheets.
Aged at 0 ° C. for 40 hours to make a sheet molding compound (SMC). This SMC was press-molded in a mold having a size of 300 mm × 100 mm at a temperature of 145 ° C. under a pressure of 50 kg / cm ² for 4 minutes to obtain a flat molded product having a thickness of 2 mm. When the uneven color and the stain of the mold of this molded product were visually observed, no uneven color and no stain of the mold were recognized. When the molding shrinkage of this SMC was measured based on JIS K-6911, it was 0.09%. The gloss of the molded product surface was measured using a surface gloss meter at a measuring angle of 60 °.
When the reflectance (%) at the time of the degree was obtained and evaluated, it was 8
It was 5.3%, and a molded article having excellent surface smoothness was obtained.

Example 6 and Comparative Example 9 A PVC / vinyl acetate copolymer as a binder (trade name: 40)
Table 4 shows 0X-110A, Nippon Bion Co., Ltd., polyurethane (trade name: Nipporan 2301, Nippon Polyurethane Co., Ltd.) and polyisocyanate (trade name: Coronate L, Nippon Polyurethane Co., Ltd.). It was dissolved in methyl ethyl ketone by mixing, and then the colored spherical particles (1) obtained in Example 1 and carbon black (Asahi
# 60 Asahi Carbon Co., Ltd.) in the amount shown in Table 4.
With sufficient stirring, carbon black-containing coating composition (1)
In addition, a carbon black-containing coating composition (1) for comparison was obtained.

Each of the carbon black-containing coating compositions was dried on a polyethylene terephthalate film to a film thickness of 10%.
It was applied to a micron size and dried at room temperature to obtain a coating for a coating film performance test. The test results were as shown in Table 4.

[0068]

[Table 4]

As is clear from Table 4, the carbon black-containing coating composition of the present invention has good dispersibility, and is excellent in antistatic properties, slip properties and friction resistance. In addition,
Each test in Table 4 is based on the following method. Antistatic property: The surface electric resistance of the coating kept in an atmosphere of 25 ° C. and 60% RH for 24 hours was measured. Friction coefficient: The dynamic friction coefficient (at 3.3 cm / sec) μ of the stainless steel ball was measured by surface measurement. Abrasion resistance: Using a Gakushin-type dyeing wear fastness tester, JIS
The abrasion state after 100 reciprocations according to the L-108445R method was visually evaluated.

…: No abrasion ×: abrasion Storage stability of liquid: The prepared carbon black-containing coating composition was stored in a room at 25 ° C. for 6 months, and a change in the state of the liquid was observed. …: No change ×: Precipitation of carbon black occurred-Example 7-50 parts by weight of the colored spherical fine particles (1) having an average particle size of 3.97 microns obtained in Example 1 and 50 parts by weight of carnauba wax The thermal transfer ink was prepared by stirring and mixing at 100 ° C. for 30 minutes. When this ink was thinly applied on a glass plate and the state of dispersion of the colored spherical fine particles was observed with a microscope, it was found that the dispersion was very good. This ink was applied to a biaxially stretched PET film having a thickness of 10 μm so that the dry thickness of the ink layer was 10 μm. The coating was performed by heating the ink to a temperature suitable for each ink to make the ink in a fluid state, and using a wire bar. The obtained heat-sensitive transfer sheet was mounted on a thermal printer and printed on paper passing through. When the image quality was evaluated based on the resolution and the presence or absence of white spots, good results were obtained. Further, the image was rubbed by applying a load of 100 g to a hemispherical stainless steel rod having one end having a diameter of 1.5 mm.
When the degree of scratching was evaluated, good results were obtained without scratches.

Example 8 20 parts of the colored spherical fine particles (1) obtained in Example 1 were mixed with polyurethane (adibic acid, 1.6-hexanediol and a molecular weight of about 3 obtained from MDI) as a binder component.
000 polyester-based polyurethane) 100 parts,
Further, 70 parts of a solvent (tetrahydrofuran / methyl ethyl ketone = 1/1) was mixed to prepare an ink ribbon coating agent, applied to the back of a thermal transfer tape, and mounted on a thermal printer to perform a performance test. The thickness of the coat layer was about 10 microns. As a result, both the slip property and the antistatic property were good.

Example 9 20 parts of the colored spherical fine particles (1) having an average particle size of 3.97 μm obtained in Example 1 and Example 7 as a binder component
100 parts of the same polyurethane and a solvent (toluene /
Methyl ethyl ketone / cyclohexane = 3/3/1) 7
A backcoat agent was prepared by mixing 0 parts by weight and applied to the back of the videotape to perform a performance test. The test method was shown below, and as a result, the abrasion resistance of the back coat layer was ◎. 1. Preparation of test sample (a) Dispersion of colored spherical fine particles.

Predetermined amounts of the colored spherical fine particles, the binder component and the solvent were charged into a container, and stirred at room temperature for 15 minutes using a propeller blade stirrer. (B) Thickness of the back coat layer. The dry film thickness was about 10 microns. 2. Performance test Abrasion resistance of the backcoat layer. The video tape was fed for a certain period of time while pressing a white cotton cloth against the back coat layer with a force of 350 g / cm ² , and the evaluation of ◎ to × was made according to the degree of contamination of the cotton cloth.

◎ No contamination of cotton cloth (no carbon black falling off) ○ Slight contamination of cotton cloth △ Pretty much contamination of cotton cloth × Notable contamination of cotton cloth (many drops of carbon black)

[0075]

As described above, the colored spherical fine particles according to the present invention are obtained by reacting a carbon black graft polymer obtained by reacting carbon black with a polymer capable of reacting with the carbon black to obtain a weight component capable of polymerizing. Distributed to
Then, since it is obtained by polymerizing the polymerizable monomer component, the carbon black graft polymer is localized near the particle surface, has excellent blackness, and has an affinity with various resins or binders. It has good properties and is used as a resin composition, a coating composition, a thermal transfer ink ribbon coating agent, a thermal transfer ink, a back coating agent for magnetic recording media, etc. by being mixed with various resins or binders.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI // C09D 7/12 C09D 7/12 11/02 11/02 (72) Inventor Tadahiro Yoneda No. 5 Nishimitabicho, Suita-shi, Osaka No. 8 Nippon Shokubai Central Research Laboratory Co., Ltd. (56) References JP-A-1-284565 (JP, A) International Publication No. 88/3545 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB Name) C09C 1/56 C08K 9/04

Claims (5)

(57) [Claims] 1. A carbon black graft polymer obtained by reacting carbon black with a polymer is dispersed in a polymerizable monomer component, and the polymerizable monomer component is subjected to aqueous suspension polymerization. In the method for producing colored spherical fine particles, the solubility parameter of the polymer to be reacted with carbon black is larger than the solubility parameter of the polymerizable monomer component or the polymer as the carbon black graft polymer. With respect to the radius (R) of the spherical fine particles.
The carbon black powder is applied to the part from the surface to R / 2.
Colored spheres containing more than 70% by weight of ft polymer
Method for producing colored spherical fine particles characterized by Rukoto obtain fine particles. 2. A method of producing colored spherical fine particles according to claim 1, wherein the amount of the carbon black graft polymer to the polymer constituting the spherical particles is made to be 1 to 100% by weight. 3. A polymer to be reacted with the carbon black producing process of colored spherical fine particles of the polymer in a claim 1 or 2, further comprising a number-average molecular weight of 500 to 1,000,000. 4. The polymer to be reacted with carbon black is at least one polymer selected from the group consisting of vinyl polymers having at least one reactive group in the molecule, polyesters and polyethers. Items 1-3
The method for producing colored spherical fine particles according to any one of the above. 5. The polymer to be reacted with carbon black has at least one compound selected from the group consisting of an aziridine group, an oxazoline group, an N-hydroxyalkylamide group, an epoxy group, a thioepoxy group and an isocyanate group in the molecule. It is a polymer having a reactive group .
5. The method for producing colored spherical fine particles according to any one of 4 .