JP2003192938A - Surface-coated inorganic pigment, pigment dispersion and coloring resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stable surface-coated inorganic pigment which is suitable for a nonaqueous or aqueous offset ink, gravure ink, coating material, inkjet ink, plastic color and color filter and is excellent in nonaggregation and fluidity; a pigment dispersion; and a coloring resin composition. <P>SOLUTION: The surface-coated inorganic pigment comprises a pigment derivative bound to the surface. The pigment dispersion comprises the surface- coated inorganic pigment dispersed in a varnish. The coloring resin composition comprises the surface-coated inorganic pigment and a thermoplastic resin. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a surface-coated inorganic pigment, a pigment dispersion and a coloring resin composition which are excellent in suitability for use, particularly non-aggregation and fluidity.

[0002]

2. Description of the Related Art Generally, when fine particles of a pigment are dispersed in a vehicle such as an offset ink, a gravure ink, and a paint, it is difficult to obtain a stable dispersion, and it is difficult to obtain a stable dispersion in the production process and the value of the obtained product. Is known to cause problems. For example, dispersions containing pigments consisting of fine particles often exhibit high viscosities, which not only makes it difficult to remove and transport the product from the disperser,
In the worst case, gelation may occur during storage and it may be difficult to use. Further, on the surface of the coating film of the color-developed product, deterioration of the gloss, poor leveling, and other defective states may occur. Further, when different kinds of pigments are mixed and used, color separation due to agglomeration and phenomena such as sedimentation may cause color unevenness or a marked decrease in coloring power of the developed product.

In order to solve the above various problems, a method of mixing a pigment derivative having an organic pigment as a base skeleton and a side chain having an acidic group or a basic group as a substituent as a dispersant is disclosed in Japanese Patent Publication No. 41-2466, USP285
5403, JP-A-63-305173, JP-A-1-247468, and JP-A-3-26767. However, although these methods are effective in dispersing organic pigments, they are not effective in dispersing inorganic pigments. Therefore, a silane coupling agent, a titanium coupling agent, a resin into which various functional groups have been introduced, etc. are used as the dispersant for dispersing the inorganic pigment, but it is sufficient as compared with the case where the organic pigment is dispersed with a pigment derivative. The present situation is that the effect is not obtained, and the invention of the technique of satisfactorily dispersing an inorganic pigment by using an organic low molecular weight compound such as a pigment derivative has been a major problem that cannot be solved.

[0004]

Therefore, the present invention is suitable for offset inks, gravure inks, paints, ink jet inks, plastic colorings, color filters, electrophoretic electronic papers, etc., and is stable and excellent in non-aggregation and fluidity. A surface-coated inorganic pigment, a pigment dispersion, and a coloring resin composition are provided.

[0005]

The present inventors have found that the dispersibility of an inorganic pigment is improved by bonding a pigment derivative to the surface of the inorganic pigment, and have completed the present invention. That is, the present invention relates to a surface-coated inorganic pigment having a surface on which a pigment derivative is bound. The present invention also relates to a pigment dispersion prepared by dispersing the above surface-coated inorganic pigment in a varnish. Furthermore, the present invention relates to a coloring resin composition containing the surface-coated inorganic pigment and a thermoplastic resin.

Examples of the inorganic pigment for forming the surface-coated inorganic pigment having the surface of the present invention bound with a pigment derivative include barite powder, barium carbonate, lime carbonate powder, precipitated calcium carbonate, silica powder, and finely divided silicic acid. Diatomaceous earth, basic magnesium carbonate, alumina white, gloss white, satin white, titanium oxide, zinc white, zinc sulfide, lead white, calcium carbonate, precipitated barium sulfate, white carbon, alumina white, kaolin clay, talc, bentonite, black Iron oxide, cadmium red, red iron oxide, molybdenum red, molybdate orange, chrome vermillion, yellow lead, cadmium yellow, yellow iron oxide, titanium yellow, chromium oxide, viridian, titanium cobalt green, cobalt green, cobalt chrome green, Victoria green , Blue, iron blue, cobalt blue, cerulean blue, cobalt silica blue, cobalt zinc silica blue, manganese violet, cobalt violet and the like.

Further, the pigment derivative constituting the present invention is a compound represented by the following general formula (1), and there are one having a basic substituent and one having an acidic substituent. Formula (1) A-B A: Organic pigment residue B: Basic substituent or acidic substituent

In the formula (1), the organic pigment constituting the organic pigment residue of A includes diketopyrrolopyrrole pigments, azo pigments such as azo, disazo, polyazo, copper phthalocyanine, and halogenated copper phthalocyanine. Phthalocyanine-based pigments such as metal phthalocyanines, aminoanthraquinones, diaminodianthraquinones, anthrapyrimidines,
Flavantron, Ant Antron, Indantron,
Anthraquinone pigments such as pyranthrone and violanthrone, quinacridone pigments, dioxazine pigments, perinone pigments, perylene pigments, thioindigo pigments, isoindolin pigments, isoindolinone pigments, quinophthalone pigments, slene pigments, metal complexes System pigments and the like.

In the formula (1), the basic or acidic substituent of B is the following formula (2), formula (3), formula (4), formula (5), formula (6) and formula (7). ) Represents at least one substituent group consisting of Formula (2)

[Chemical 1] Formula (3)

[Chemical 2]

Equation (4)

[Chemical 3] Formula (5)

[Chemical 4]

Equation (6)

[Chemical 5] Formula (7)

[Chemical 6]

X: --SO _2- , --CO--, --CH ₂ NHC
It represents OCH ₂ —, —CH ₂ — or a direct bond. n represents an integer of 1 to 10. R ₁ and R ₂ : each independently, an alkyl group which may be substituted, an alkenyl group which may be substituted, a phenyl group which may be substituted, or a combination of R ₁ and R ₂ Represents an optionally substituted heterocycle containing a nitrogen, oxygen or sulfur atom. R ₃ represents an optionally substituted alkyl group, an optionally substituted alkenyl group or an optionally substituted phenyl group.

R ₄ , R ₅ , R ₆ , R ₇ : each independently represents a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkenyl group or an optionally substituted phenyl group. . _{Y: -NR 8 -Z-NR 9} - or a direct bond. R ₈ and R ₉ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkenyl group, or an optionally substituted phenyl group. Z: represents an optionally substituted alkylene group, an optionally substituted alkenylene group, or an optionally substituted phenylene group. P: represents a substituent represented by the formula (8) or a substituent represented by the formula (9). Q: represents a hydroxyl group, an alkoxyl group, a substituent represented by the formula (8) or a substituent represented by the formula (9).

Equation (8)

[Chemical 7] Formula (9)

[Chemical 8]

M: represents a hydrogen atom, a calcium atom, a barium atom, a strontium atom, a manganese atom or an aluminum atom. i: represents the valence of M. R ₁₀ , R ₁₁ , R ₁₂ , and R ₁₃ are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkenyl group, an optionally substituted phenyl group, or a polyoxyalkylene group. Represents

Examples of the amine component used to form the formulas (1) to (5), (8) and (9) include dimethylamine, diethylamine, N, N.
-Ethylisopropylamine, N, N-ethylpropylamine, N, N-methylbutylamine, N, N-methylisobutylamine, N, N-butylethylamine, N,
N-tert-butylethylamine, diisopropylamine, dipropylamine, N, N-sec-butylpropylamine, dibutylamine, disec-butylamine, diisobutylamine, N, N-isobutyl-sec
-Butylamine, diamylamine, diisoamylamine, dihexylamine, di (2-ethylhexyl) amine, dioctylamine, N, N-methyloctadecylamine, didecylamine, diallylamine, N, N-ethyl-1,2-dimethylpropylamine , N, N-methylhexylamine, dioleylamine, distearylamine, N, N-dimethylaminomethylamine, N, N-dimethylaminoethylamine, N, N-dimethylaminoamylamine, N, N-dimethylaminobutylamine,
N, N-diethylaminoethylamine, N, N-diethylaminopropylamine, N, N-diethylaminohexylamine, N, N-diethylaminobutylamine,
N, N-diethylaminopentylamine, N, N-dipropylaminobutylamine, N, N-dibutylaminopropylamine, N, N-dibutylaminoethylamine,
N, N-dibutylaminobutylamine, N, N-diisobutylaminopentylamine, N, N-methyl-laurylaminopropylamine, N, N-ethyl-hexylaminoethylamine, N, N-distearylaminoethylamine, N, N -Dioleylaminoethylamine, N,
N-distearylaminobutylamine, piperidine, 2
-Pipecoline, 3-pipecoline, 4-pipecoline, 2,
4-Lupetidine, 2,6-Lupetidine, 3,5-Lupetidine, 3-piperidinemethanol, pipecolic acid, isonipecotic acid, methyl isonicopetate, ethyl isonicopetate, 2-piperidineethanol, pyrrolidine,
3-hydroxypyrrolidine, N-aminoethylpiperidine, N-aminoethyl-4-pipecoline, N-aminoethylmorpholine, N-aminopropylpiperidine, N-
Aminopropyl-2-pipecoline, N-aminopropyl-4-pipecoline, N-aminopropylmorpholine, N
-Methylpiperazine, N-butylpiperazine, N-methylhomopiperazine, 1-cyclopentylpiperazine, 1
-Amino-4-methylpiperazine, 1-cyclopentylpiperazine and the like can be mentioned.

The amine component used to form the sulfonic acid amine salt of the formula (7) may be any of primary, secondary, tertiary and quaternary amines. Hexylamine, heptylamine, octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine which may have a chain , Amines such as nonadecylamine and eokosylamine, and unsaturated amines corresponding to the respective carbon numbers.

The secondary, tertiary and quaternary amines include dioleylamine, distearylamine, dimethyloctylamine, dimethyldecylamine, dimethyllaurylamine, dimethylstearylamine, dilaurylmonomethylamine, trioctylamine and dimethyldidodecyl. Ammonium chloride, dimethyldioleylammonium chloride, dimethyldidecylammonium chloride, dimethyldioctylammonium chloride, trimethylstearylammonium chloride, dimethyldistearylammonium chloride, trimethyldecylammonium chloride, trimethylhexadecylammonium chloride, trimethyloctadecylammonium chloride, dimethyldodecyltetrachloride Decyl ammonium chloride, dimethyl hexadecyl Octadecyl ammonium chloride, and the like. Further, R ₁₀ , R ₁₁ in the formula (7),
When either R ₁₂ or R ₁₃ represents a polyoxyalkylene group, examples thereof include a polyoxyethylene group and a polyoxypropylene group.

In the surface-coated inorganic pigment having a pigment derivative bonded to the surface of the present invention, the bond between the pigment derivative and the inorganic pigment may be a physical bond or a chemical bond. The ratio of the pigment derivative to the inorganic pigment is preferably 1 to 100 parts by weight, more preferably 5 to 50 parts by weight, based on 100 parts by weight of the inorganic pigment.

The surface-coated inorganic pigment of the present invention having a pigment derivative bonded to the surface thereof is preferably produced by a mechanochemical method. The mechanochemical method is a method utilizing a mechanochemical reaction which is a chemical reaction that occurs based on a mechanical action or proceeds in the coexistence of a chemical action and a mechanical action, and any known method can be applied. Apparatuses such as a stirrer, a mixer, and a crusher used in the mechanochemical method are not particularly limited, but for example, an attritor, a kneader, a three-roll mill, a two-roll mill, a ball mill, a roller mill, a stone mill mill, Hybridizer (Nara Machinery Co., Ltd.), Mechanomicros (Nara Machinery Co., Ltd.), Mechanofusion system AMS (Hosokawa Micron Co., Ltd.), etc. can be used.

The mechanochemical method is preferably carried out in the presence of a silicon compound, titanium compound or resin, but most preferably in the presence of a silicon compound or titanium compound. By carrying out the mechanochemical method in the presence of the above compound, on the surface of the inorganic pigment,
Mixtures of silicon compounds and pigment derivatives, titanium compounds and pigment derivatives, or resins and pigment derivatives can be combined. Further, when the mechanochemical method is carried out in the presence of a resin, it is conceivable that the resin molecules may be cleaved or bonded.

Examples of the silicon compound include alkoxysilane such as tetramethoxysilane and tetraethoxysilane, polysiloxane and the like. Also. Among the alkoxysilanes, it is particularly preferable to use a silane coupling agent. The silane coupling agent is an alkoxysilane in which an alkoxy group such as a methoxy group, an ethoxy group, and an isopropoxy group is bonded to a silicon atom and another organic functional group, and is not particularly limited. As the silane coupling agent, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, phenyltrimethoxysilane,
Diphenyldimethoxysilane, isobutyltrimethoxysilane, decyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- ( 2-Aminoethyl) aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-ureidopropyltriethoxysilane and the like can be used. Examples of commercially available silicon compounds include LS series manufactured by Shin-Etsu Chemical Co., Ltd.

Examples of the titanium compound include alkoxytitanium such as tetraisopropoxytitanium and the like, but it is particularly preferable to use a titanium (titanate type) coupling agent. The titanium (titanate-based) coupling agent is an alkoxytitanium in which an alkoxy group such as a methoxy group, an ethoxy group, an isopropoxy group and the other organic functional groups are bonded to a titanium atom, and is not particularly limited. Examples of titanium (titanate-based) coupling agents include Plane Act series KRTTS, KR46B, and KR5 manufactured by Ajinomoto Fine-Techno Co., Inc.
5, KR41B, KR38S, KR138S, KR23
8S, 338X, KR44, KR9SA, etc. can be used.

Alkoxysilane and alkoxytitanium are compounds represented by the following formula (10), and when treated by the mechanochemical method, the alkoxy group reacts under the influence of water, heat, etc. to form a dimer-multimer compound. It is also possible to produce organosilane compounds and organotitanium compounds such as oligomers, polymers and the like. In this case, the surface-coated inorganic pigment of the present invention is a surface-coated inorganic pigment in which a mixture of an alkoxysilane and / or an organosilane compound produced from an alkoxysilane and a pigment derivative is bonded to the surface, or an alkoxytitanium and And / or a surface-coated inorganic pigment obtained by combining a mixture of an organotitanium compound formed from alkoxytitanium and a pigment derivative. Formula (10)

[Chemical 9] L: represents a silicon atom or a titanium atom. E: represents an alkoxy group. G: represents an alkyl group or an aryl group which may contain a hetero atom. a: represents an integer of 1 to 4.

The resin is not particularly limited, and examples thereof include petroleum resin, casein, shellac, rosin-modified maleic acid resin, rosin-modified phenol resin, nitrocellulose, cellulose acetate butyrate, cyclized rubber, chlorinated rubber, Oxidized rubber, hydrochloric acid rubber, phenolic resin,
Alkyd resin, polyester resin, unsaturated polyester resin, amino resin, epoxy resin, vinyl resin, vinyl chloride, vinyl chloride-vinyl acetate copolymer, acrylic resin, methacrylic resin, polyurethane resin, silicone resin, fluorine resin, drying oil, Synthetic drying oil, styrene-modified maleic acid, polyamide resin, chlorinated polypropylene, butyral resin, vinylidene chloride resin and the like can be used.

The amount of the silicon compound, titanium compound or resin used when carrying out the mechanochemical method is preferably 0.1 to 50 parts by weight with respect to 100 parts by weight of the inorganic pigment. The mechanochemical method according to the present invention comprises mixing an inorganic pigment and a pigment derivative in the presence or absence of a silicon compound, a titanium compound or a resin to bond the pigment derivative to the surface of the inorganic pigment.

When carrying out the mechanochemical method, an organic solvent or water may be added to wet the pigment derivative and the inorganic pigment to be treated, and the silicon compound, titanium compound or resin may be dissolved in the organic solvent or water. Alternatively, it may be added after being dispersed. When carrying out the mechanochemical method, an inorganic acid or an inorganic base may be added.

As an example of the mechanochemical method according to the present invention, 100 parts by weight of an inorganic pigment, 30 parts by weight of a pigment derivative, 10 parts by weight of a silane coupling agent and 20 parts of ethanol are added.
Examples include a method in which the liquid dispersed in parts by weight is added to a ball mill containing steel balls having a diameter of 1 cm and treated.
The inorganic pigment, the pigment derivative, and the ethanol dispersion of the silane coupling agent may all be mixed from the beginning, but the ethanol dispersion of the inorganic pigment and the silane coupling agent may be first treated and then the pigment derivative may be added. Alternatively, an ethanol dispersion of a pigment derivative and a silane coupling agent may be treated first, and then an inorganic pigment may be added.

The surface-coated inorganic pigment of the present invention can be made into a pigment dispersion by dispersing it in a solvent-based or water-based varnish. As an example of the resin contained in the varnish,
Petroleum resin, casein, shellac, rosin-modified maleic acid resin, rosin-modified phenol resin, nitrocellulose,
Cellulose acetate butyrate, cyclized rubber, chlorinated rubber, oxidized rubber, hydrochloric acid rubber, phenolic resin, alkyd resin, polyester resin, unsaturated polyester resin, amino resin, epoxy resin, vinyl resin, vinyl chloride, vinyl chloride-vinyl acetate Examples thereof include polymers, acrylic resins, methacrylic resins, polyurethane resins, silicone resins, fluororesins, drying oils, synthetic drying oils, styrene-modified maleic acid, polyamide resins, chlorinated polypropylene, butyral resins and vinylidene chloride resins.

The pigment dispersion of the present invention is prepared by mixing the surface-coated inorganic pigment of the present invention with various organic solvents or water, a resin, and if necessary, additives, dispersants and the like, and dispersing using various dispersing machines. It can be manufactured. The disperser is not particularly limited, and for example, a horizontal sand mill, a vertical sand mill, an annular bead mill, an attritor or the like can be used.

The surface-coated inorganic pigment of the present invention can be made into a coloring resin composition by kneading with a thermoplastic resin. Examples of the thermoplastic resin include polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymer (including random or block copolymer), polystyrene, ABS resin, AS resin, polyvinyl chloride, polyester, polyacetal, and the like.
Polycarbonate, polyaromatic ether, polyaromatic ester, polysulfone and the like can be mentioned. As the kneading, a batch-type kneader such as a Banbury mixer, a twin-screw kneader, a single-screw extruder having a kneading function, and a rotor-type twin-screw kneader can be used. When a polyolefin resin is used as the thermoplastic resin, the kneading is preferably performed at 130 to 230 ° C, and when polyethylene is used among the polyolefin resins, the kneading is more preferably performed at 130 to 200 ° C. After kneading, the coloring resin composition can be made into a desired shape (pellet, granule, or particle) by pulverization, cutting, granulation, or the like, and can be used for film formation or the like.

The surface-coated inorganic pigment, pigment dispersion and coloring resin composition of the present invention may contain various additives such as commercially available dispersants and surfactants. Specifically, as an additive, Big Chemie Disperbyk or Disperb
yk-101, 103, 107, 108, 110, 11
1, 116, 130, 140, 154, 161, 16
2, 163, 164, 165, 166, 170, 17
1, 174, 180, 181, 182, 183, 18
4, 185, 190, 2000, 2001 or Anti-T
erra-U, 203, 204 or BYK-P104, P1
04S, 220S or Lactimon, Lactimon-WS or Bykumen, SOLSPERSE-3000, 9 manufactured by Abyssia.
000, 13240, 13650, 13940, 170
00, 18000, 20000, 21000, 2400
0, 26000, 27000, 28000, 3184
5, 32000, 32500, 32600, 3475
0, 36600, 38500, 41000, 4109
0,53095, EFKA-4 manufactured by Fuka Chemicals
6, 47, 48, 452, LP4008, 4009, L
P4010, LP4050, LP4055, 400, 4
01, 402, 403, 450, 451, 453, 45
40, 4550, LP4560, 120, 150, 15
01, 1502, 1503 and the like.

The surface-coated inorganic pigment, pigment dispersion or coloring resin composition of the present invention is a non-aqueous or water-based offset ink, gravure ink, paint, ink jet ink, plastic coloring, color filter, electrophoretic electronic paper, etc. Available for

[0034]

EXAMPLES Production examples, examples and comparative examples according to the present invention will be shown below. The following "parts" represent "parts by weight". The chemical structural formulas of the pigment derivatives used in Examples and Comparative Examples are shown below. Pigment derivative 1

[Chemical 10] CuPc represents a copper phthalocyanine residue.

Pigment derivative 2

[Chemical 11] Pigment derivative 3

[Chemical 12] Pigment derivative 4

[Chemical 13]

Pigment derivative 5

[Chemical 14] Pigment derivative 6

[Chemical 15] Pigment derivative 7

[Chemical 16]

Pigment derivative 8

[Chemical 17] Pigment derivative 9

[Chemical 18]

Production of surface-coated inorganic pigments having a pigment derivative attached to the surface. [Production Example 1] Inorganic pigment Pigment White 6 was added to a 1 L ball mill containing 2 kg of 1/2 inch steel balls.
0 parts, 8 parts of a silane coupling agent (“LS-5300” manufactured by Shin-Etsu Chemical Co., Ltd.) and 18 parts of pigment derivative 1 were added, and mechanochemical treatment was carried out for 24 hours to bond the pigment derivative to the surface. Surface-coated inorganic pigment 1 was obtained. [Production Example 2] Inorganic pigment Pigment White on 1L kneader
6 parts by 100 parts, a titanate coupling agent (Ajinomoto Fine Techno Co., Ltd. "KRTTS") 15 parts, and a pigment derivative 6 by 40 parts were added, and mechanochemical treatment was performed for 10 hours to bond the pigment derivative to the surface. Surface-coated inorganic pigment 2 was obtained.

[Production Example 3] 100 parts of inorganic pigment Pigment White 6, 20 parts of rosin ester resin ("Ester gum AT" manufactured by Arakawa Chemical Industry Co., Ltd.), and 15 of pigment derivative 2
After mixing, the mixture was subjected to mechanochemical treatment for 5 hours with a stone mill to obtain a surface-coated inorganic pigment having a surface bound with a pigment derivative to obtain a surface-coated inorganic pigment 3. [Production Examples 4 to 9] Surface-coated inorganic pigments 4 to 9 each having a pigment derivative bonded to the surface thereof were obtained by the methods shown in Table 1.

[0040]

[Table 1]

Silicon compound (1): Silane coupling agent (“LS manufactured by Shin-Etsu Chemical Co., Ltd.”
-5300 ") (2): Silane coupling agent (Shin-Etsu Chemical Co., Ltd." LS
-2940 ") (3): Silane coupling agent (Shin-Etsu Chemical Co., Ltd." LS
-5118 ") (4): Silane coupling agent (Shin-Etsu Chemical Co., Ltd." LS
-3150 ") Titanium compound (1): Titanate coupling agent (" KR TTS "manufactured by Ajinomoto Fine Techno Co., Ltd.) (2): Titanate coupling agent (" KR 46B "manufactured by Ajinomoto Fine Techno Co., Ltd.) Resin (1): Rosin ester resin ("Ester gum AT" manufactured by Arakawa Chemical Industry Co., Ltd.) (2): Rosin-modified phenol resin (Arakawa Chemical Industry Co., Ltd.)
Made by "Tamanor 135")

[Examples 1 to 9 and Comparative Examples 1 to 9] Production and Evaluation of Pigment Dispersion In order to evaluate the performance of the pigment dispersion of the present invention, Production Example 1
The following coating materials were prepared using surface-coated inorganic pigments 1 to 9 each having a pigment derivative bonded to the surface produced in steps # 9 to # 9. Dispersion was performed with a paint shaker using 3 mmφ steel balls. The viscosity of the obtained coating material was measured with a B-type viscometer, and the performance of the dispersion was evaluated by the viscosity and the TI value (the lower the viscosity, the better; the closer the TI value is to 1, the better). Also,
The obtained paint was spread on a PET film, and 60 ° gloss was measured with a gloss meter for evaluation (the higher the gloss, the better). The results are shown in Table-2.

[0043] (Paint component)   Surface-coated inorganic pigment with a pigment derivative bonded to the surface   Alkyd resin (containing xylene)   Melamine resin (containing xylene)   Thinner (cyclohexanone / xylene / n-butanol = 6/2/2 (weight ratio)) (Paint formulation)   Surface-coated inorganic pigment having a pigment derivative bonded to the surface: 10 parts by weight   Alkyd resin (solid content): 30 parts by weight   Melamine resin (solid content): 10 parts by weight   Thinner + xylene: 50 parts by weight

In Comparative Examples 1 to 9, coating materials were prepared by using a simple mixture of the inorganic pigment and the pigment derivative shown in Table 3 instead of the surface-coated inorganic pigment having the surface bound with the pigment derivative. . As the mere mixture of the inorganic pigment and the pigment derivative, a mixture was used in which the inorganic pigment and the pigment derivative were placed in a glass bottle, and a grinding medium such as steel balls or glass beads was not placed, and the mixture was simply mixed for one hour with a paint shaker. Table 3 shows the mixing ratio. As shown in Table 2, the pigment dispersion of the present invention showed good viscosity, TI value and gloss as compared with the comparative example.

[0045]

[Table 2]

[0046]

[Table 3]

Example 10 38 parts by weight of a polyethylene resin, 60 parts by weight of the surface-coated inorganic pigment 1 having a pigment derivative bonded to the surface of Production Example 1 and 2 parts by weight of zinc stearate were mixed, and the rotor type 2 was mixed. The resin composition for coloring (masterbatch) was obtained by kneading at 150 ° C. using a shaft kneader, extruding, cooling and pelletizing. Then, the pigment concentration 3
The above masterbatch and the above polyethylene resin were blended so as to be 0% by weight, and a T die film molding machine (manufactured by Toyo Seiki Co., Ltd.) was used to mold at a temperature of 340 ° C. and a rotation speed of 60 r.
While melted at pm, a film-like melt mixture having a film thickness of 30 μm is melt-extruded and laminated on paper to obtain a resin-coated paper, and a surging state (high-temperature high-speed processability) when the resin-coated paper is obtained and obtained. The state of the coated surface (film surface) on the resin-coated paper was visually observed.

[Comparative Example 10] Instead of the surface-coated inorganic pigment 1 having a pigment derivative bonded to the surface, shown in Table 3 below.
In the same manner as in Example 10 except that the mere mixture 1 of the inorganic pigment and the pigment derivative was used, the surging state (high-temperature high-speed processability) when obtaining the resin-coated paper and the coated surface on the obtained resin-coated paper ( The state of the film surface) was visually observed. In Comparative Example 10, there was surging (film pulsation) and there was a problem in workability, and the film surface also had film cracks, spots, and pinholes, whereas in Example 10, there was no surging and there was no film surface. Was also very good.

[0049]

By using a surface-coated inorganic pigment having a pigment derivative bonded to the surface, a pigment dispersion or a coloring resin composition having good dispersibility can be obtained, and the dispersibility of the inorganic pigment can be increased. It has become possible to improve.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09C 3/04 C09C 3/04 3/08 3/08 C09D 201/00 C09D 201/00 F term (reference) 4J002 AA011 BB031 BB121 BC001 BC031 BC061 BN151 CF001 CG001 CH061 CN011 DE136 DJ006 FB086 FD096 4J037 AA08 AA09 AA10 AA11 AA15 AA17 AA19 AA HA HAHAHA 266 HA07 HA266 HAEE HAEE HAJEEE EE28 EA28 HAEEHAEE EE28 EA28 HA018 EA28 HA038 EE28 EA28 HA01 EA28 HA038 EE28 EE28 EA28 HA038 HAEE15

Claims (7)

[Claims] 1. A surface-coated inorganic pigment having a surface bound with a pigment derivative. 2. The surface-coated inorganic pigment according to claim 1, wherein the surface-coated inorganic pigment is produced by a mechanochemical method. 3. The surface-coated inorganic pigment according to claim 2, wherein the mechanochemical method is carried out in the presence of a silicon compound. 4. The surface-coated inorganic pigment according to claim 2, wherein the mechanochemical method is carried out in the presence of a titanium compound. 5. The surface-coated inorganic pigment according to claim 2, wherein the mechanochemical method is carried out in the presence of a resin. 6. A pigment dispersion comprising the surface-coated inorganic pigment according to claim 1 dispersed in a varnish. 7. A coloring resin composition comprising the surface-coated inorganic pigment according to claim 1 and a thermoplastic resin.