JPH0788455B2 - Pigment composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a pigment composition, and more particularly to an organic pigment composition useful as a paint or a printing ink.

(Prior Art and Problems Thereof) Various organic pigments are conventionally known, and since these organic pigments have high sharpness and coloring power, they are widely used as color materials for paints and printing inks. , When used in paints and printing inks, especially when those media are organic solvents, the organic pigments dispersed in these media often cause agglomeration and crystal growth of particles, resulting in sharpness and coloring. There are various problems such as a decrease in strength, a thickening phenomenon with time during storage, which makes it unusable and a decrease in the gloss of the coating film surface. Further, when the organic pigment and the inorganic pigment are mixed and used, so-called color separation occurs in which these pigments are separated from each other in the paint.

As a method for solving such a problem, a surface treatment method using various surface treatment agents for organic pigments has been proposed, but for example, it has a selectivity for a vehicle of a paint or a printing ink, Although the vehicle shows good results, other vehicles have no effect or have an adverse effect, so that sufficient problem solving has not been achieved.

For example, JP-A-58-215461 discloses the use of an acrylic polymer having a tertiary amino group as a pigment treating agent. Since the acrylic polymer used in this method is a basic polymer, it is soluble in an aqueous acid solution, but is insoluble in a medium to alkaline aqueous solution, so that the pigment is effectively coated with the polymer. In order to achieve this, it is necessary to make the polymer in the form of an emulsion during the production of the polymer or the treatment of the pigment, and at this time, the use of a surfactant is indispensable. Therefore, a surfactant is inevitably mixed in the obtained treated pigment, and when this treated pigment is used in paints or printing inks, the presence of the surfactant reduces the water resistance of the coating film or the printed matter, and There is a problem that deterioration occurs, and there is a problem that it has selectivity for the vehicle and is almost ineffective in preventing color separation.

(Means for Solving Problems) As a result of earnest research to solve the problems of the prior art as described above, the present inventor found that when a specific (meth) acrylic acid-based polymer is used as a treating agent for an organic pigment. Is a pigment composition having excellent sharpness, tinting strength, color separation prevention property, storage stability, non-selectivity for vehicle, etc. without using any surfactant during the treatment of organic pigments. The present invention has been completed based on this finding.

That is, the present invention comprises a mixture of a solid, aqueous paste-like or slurry-like organic pigment and a solution of a solid (meth) acrylic acid-based polymer or a non-aqueous solvent thereof. A pigment composition for dissolving and / or dispersing in an organic solvent, wherein the polymer is a polymer having the following monomer composition (a) and ratio (b).

(A) (a) (meth) acrylic acid-based monomer represented by the following general formula (I) (b) (meth) acrylic acid (c) (a) and a monomer copolymerizable with (b) (b) The total amount of (a) and (b) is 85-100 in the total polymer.
% By weight, (c) is 0 to 15% by weight, and the weight ratio of (a) to (b) is 100 to (b) 3 to 20.

(However, R ₁ in the above formula is H or CH ₃ , X is a C ₂ or more alkylene group which may have a hydroxyl group, and R ₂ and R ₃ may have a hydrogen atom or a hydroxyl group. A good alkyl group, but not a hydrogen atom at the same time.) Next, the present invention will be described in more detail.
The above-mentioned (meth) acrylic (this term means both acrylic and methacrylic) acid-based polymers, which mainly characterize the present invention, have a tertiary amino group that is basic in their structure and an acidic group. It is a polymer having a certain carboxyl group at the same time, and its main feature is that it is a so-called amphoteric polymer.

By using such an amphoteric polymer as a treating agent for pigments, various problems of the prior art are solved and the object of the present invention is achieved.

The (meth) acrylic acid-based polymer is obtained by copolymerization of (meth) acrylic acid (b) and the monomer (a) of the formula (I). Such a monomer of the formula (I) is known per se, and any of the known monomers can be used. Examples of suitable monomers for the purpose of the present invention include (meth) acrylic acid and dimethylethanolamine.
It is an ester compound with an alkanolamine such as diethylethanolamine, dipropylethanolamine, dibutylethanolamine, dimethylpropanolamine and dimethylbutanolamine, or a salt thereof or a quaternary ammonium salt.

Further, as the third monomer, a monomer (c) copolymerizable with the above (a) and (b), for example, another monomer such as styrene, (meth) acrylic acid alkyl ester, (meth) acrylic acid hydroxyalkyl ester, and the like. Can also be copolymerized at the same time. However, when these third monomers are copolymerized, the amount of these third monomers (c) is preferably 0 to 15% by weight based on the total amount of the monomers. If the amount is more than 10% by weight, the effect peculiar to the present invention decreases, which is not preferable.

Further, the ratio of the (meth) acrylic acid (b) to the monomer (a) of the above formula (I) used is such that the weight ratio of both of them is 100 parts by weight of the monomer (a) of the formula (I) (meth) acrylic acid ( A range in which b) is 3 to 20 parts by weight is preferable. If the amount of (meth) acrylic acid used is too large, the basicity of the polymer will be insufficient, while if the amount of (meth) acrylic acid used is too small, the acidity of the polymer will be insufficient, and the solubility of the polymer in water or It lacks dispersion stability and requires the use of surfactants when treating pigments, and the sharpness of paints and printing inks, coloring power, storage stability, color separation prevention, non-selectivity for vehicles, etc. It is not preferable because it decreases.

The molecular weight of the amphoteric (meth) acrylic acid-based polymer as described above is not particularly limited, but generally about 1,000 to 200,000 is suitable. The non-polymerization method may be any conventionally known copolymerization method, but a preferred method is an organic solvent which dissolves the monomer and the produced polymer, and an organic solvent which is miscible with water to some extent, for example, an alcohol or an ester. Hydrophilic solvents such as, ketones, ethers, glycols and the like. By using such a hydrophilic organic solvent to obtain a polymerization solution, it can be immediately used as a treating agent for pigments. That is, in general, organic pigments are often produced in an aqueous medium, and are subjected to various pigmentation treatments in an aqueous medium. Therefore, the above solution is added as it is during the production or treatment of such pigments. Because you can do it. Of course, a solvent other than the above may be used, or the polymer may be once separated and then used. Furthermore,
Depending on the polymer, the solubility in a solvent or water may be insufficient. In such a case, another solvent having a large dissolving power or an acid or alkali may be used. .

The organic pigment used in the present invention may be any conventionally known organic pigment, for example, phthalocyanine type, anthraquinone type, quinacridone type, azo type, indigo type, quinophthalone type, isoindolinone type, quinazoline type. Any organic pigment such as dioxazine-based, anthrone-based, perinone-based, perylene-based, and picoline-based can be used, and a mixed pigment obtained by mixing these with an inorganic pigment may also be used.

The amount of the (meth) acrylic acid-based polymer added to the organic pigment is generally (meth) per 100 parts by weight of the organic pigment.
Acrylic acid polymer is about 0.1 to 20 parts by weight, the effect of the present invention is difficult to obtain when the amount added is less than 0.1% by weight, while the use of an amount exceeding 20% by weight rather results in various physical properties of the pigment. It is not preferable because it damages.

The method for treating a pigment with the (meth) acrylic acid-based polymer is such that, when the pigment is in the form of a lump or a powdery solid, the pigment is pulverized or mixed in a mixer such as a tumbler or a high-speed rotary mixer while A method in which a solution of a (meth) acrylic acid-based polymer in a non-aqueous solvent is gradually added and uniformly mixed, and when the pigment is an aqueous paste, both are mixed and uniformly mixed and kneaded with a roll or a kneader. In the case of a pigment in the form of a slurry, a method of uniformly mixing with a mixer such as a Tyzor bar, etc., and in the case of an azo pigment,
A method of adding it to the aqueous medium at the time of its production may be used.

After the pigment is treated with the (meth) acrylic polymer as described above, it is directly dried, or the treated pigment is filtered, dried and pulverized to obtain a solid pigment composition of the present invention. can get. Further, as another treatment method, there is a method in which the solid (meth) acrylic polymer and the pigment are directly mixed on a roll. In this case, they can be mixed in the presence of varnish or the like for easy handling.

(Operation / Effect) According to the present invention as described above, when the pigment composition of the present invention is used as a coloring material for paints or printing inks, these paints or printing inks are solvent-based paints or printing inks. However, since the pigment has good dispersibility and fluidity, and the dispersed pigment does not aggregate even if it is retained for a long time, a decrease in coloring power, sharpness, etc. and a thickening phenomenon may occur during storage. Absent. Therefore, high sharpness even when used after long-term storage,
It is possible to provide a coating film or printed matter having coloring power, surface gloss and the like.

Furthermore, the pigment composition of the present invention does not cause color separation in a paint or the like even when used in combination with an inorganic pigment having a large specific gravity such as titanium oxide, and has selectivity for various vehicles. Similarly, for example, it has good fluidity and dispersion for baking type vehicles such as melamine / alkyd resin and acrylic / melamine resin, and also for room temperature drying type vehicles such as NC lacquer and NC / polyamide resin. It has high suitability in terms of properties, dispersion stability and the like, and provides a coating film or printed matter with excellent gloss.

Furthermore, since the pigment composition of the present invention does not need to use any surfactant during its production, it does not cause various defects such as deterioration of water resistance of a coating film or a printed matter due to the presence of these surfactants. It is a thing.

Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. In the text, “part” or “%” is based on weight unless otherwise specified.

Example 1 6.7 parts of methacrylic acid and 94.3 parts of dimethylaminoethyl methacrylate are added to 230 parts of methyl ethyl ketone and uniformly dispersed.

6.3 parts of azobisisobutyronitrile (hereinafter referred to as AIB
(Referred to as N) as a polymerization initiator, and gradually heated to 65 ° C with stirring. Further, the polymerization is completed at 65 ° C. or higher for 5 hours and then cooled to room temperature. At this time, the copolymer was dissolved in the solvent, and the content of the active ingredient in the solution was 30%.
Met.

Next, 6.5 parts of the above-mentioned copolymer solution is added to 400 parts of a 10% aqueous suspension of CI Pigment Orange 36, and the mixture is stirred for about 30 minutes and uniformly mixed into the pigment. The treated pigment suspension is filtered and the resulting pigment cake is dried in a conventional hot air drier (80-100).
After being dried at (° C.) for 10 hours, the pigment composition of the present invention was obtained by pulverizing with a usual pulverizer.

Example 2 To 100 parts of water was added 4.5 parts of the copolymer solution used in Example 1,
While stirring with a dissolver, 140 parts of CI Pigment Orange 36 water paste cake (pigment content 35%) is added to peptize. After the addition of the entire amount is completed, the cake is deflocculated for another 30 minutes so that the cake is completely unraveled to obtain a uniform pigment suspension. This suspension was filtered, dried and pulverized in the same manner as in Example 1 to obtain the pigment composition of the present invention.

Example 3 900 parts of the water paste cake of CI Pigment Orange 36 (pigment content 35%) used in Example 2 and 10 parts of the copolymer solution used in Example 1 were added to a 1.5 l volume kneader and kneaded thoroughly. . The obtained creamy pigment composition was dried and pulverized to obtain the pigment composition of the present invention.

Example 4 In order to evaluate the effects of the pigment compositions obtained in Examples 1 to 3, paints having the following composition were prepared.

Formulation (1) Face agent 10 parts Alkyd resin varnish (nonvolatile content 60%) 26.4 parts Melamine resin varnish (nonvolatile content 50%) 13.6 parts Thinner (xylene / n-butanol = 8/2) 20 parts Add after dispersion Mixed varnish (alkyd / melamine = 7/3 (solid content)) 48.3 parts Blend (2) Face agent 10 parts Oil-free polyester resin varnish (nonvolatile content 60%) 26.4 parts Melamine resin varnish (nonvolatile content 50%) 13.6 parts Swazol # 1500 (Maruzen Oil Co., Ltd.) 20 parts Mixed varnish added after dispersion (polyester / melamine = 7/3 (solid content)) 48.3 parts Put the above compound in a container, add glass beads and paint shaker (red) (Manufactured by Devil) and dispersed to prepare a paint.

Comparative Example 1 Using CI Pigment Orange 36 before treatment, Examples 1 to 1
A coating material was prepared according to Example 4 together with the pigment composition of Example 3, and the physical properties were comparatively evaluated by the following evaluation methods, and the results shown in Table 1 below were obtained.

Evaluation method (1) Dispersibility Paint shaker (manufactured by Red Devil Co.) with dispersion blending
Disperse with, and judge by the time until the particle size reaches 10 μm or less with a grind gauge. Judgment was made in three stages: ○: within 30 minutes, △: within 60 minutes, ×: over 60 minutes.

(2) Fluidity The obtained paint was used with a B-type viscometer (manufactured by Tokyo Keiki Co., Ltd.) to produce a liquid
Measure the viscosity of 2, 30, 60 rpm. (Measurement temperature: 25 ± 2 ℃)
Each viscosity value and TI value (n6 / n60) were used for judgment. Judgment was made in three steps of TI value: ○: 1.2 to 1.5, △: 1.5 to 2.0, ×: 2.0 or more.

(3) Visibility The final paint viscosity of the obtained paint is 23 with Ford Cup # 4.
Adjust it with a thinner so that it will be in seconds, spray it on a tin plate with an air spray gun, then bake and harden it, and visually and visually measure the incident angle 60 ° gloss and 20 ° gloss to comprehensively evaluate the sharpness of the coated surface. An evaluation was made. Judgment is ○: Yu
Δ: good, ×: inferior.

(4) Dispersion stability Put the obtained coating material in a constant temperature bath at 25 ℃ × 30 days and 50 ℃ ×
The above-mentioned (2) fluidity and (3) image clarity were evaluated for the aging enamel stored under the condition of 7 days.

The judgment was made in three stages of ◯: good, Δ: rather good, and x: bad.

Example 5 13.7 parts of methacrylic acid and 102.6 parts of dimethylaminoethyl methacrylate are added to 100 parts of ethyl methyl ketone and uniformly dispersed. Then add 7.4 parts of AIBN and slowly heat to 65 ° C with stirring.

Further, the polymerization is completed at 65 ° C. for 5 hours and then cooled to room temperature. The active ingredient in the obtained copolymer solution was 51%. Further, 3.9 parts of the above copolymer solution was uniformly mixed with CI Pigment Orange 36 in the same manner as in Example 1 to obtain a pigment composition of the present invention.

Example 6 8.2 parts of acrylic acid, 5 parts of butyl acrylate and 109.7 parts of dimethylaminoethyl methacrylate are uniformly dispersed in a mixed solvent of 200 parts of ethyl methyl ketone and 100 parts of methyl alcohol. Add 7.4 parts of AIBN to give a boiling point of 5
Polymerize for a period of time. The active ingredient in the obtained copolymer solution is
It was 28.5%.

In the same manner as in Example 1, 7 parts of the above-mentioned copolymer solution was uniformly mixed with CI Pigment Orange 36 to obtain a pigment composition of the present invention.

Example 7 5.6 parts of acrylic acid and 102.7 parts of diethylaminoethyl acrylate were added to 230 parts of methyl ethyl ketone, 6.3 parts of AIBN was further added, and polymerization was carried out at 65 ° C. or higher for 5 hours to obtain a copolymer solution of 31% of active ingredient. Got

6.5 parts of this copolymer solution was treated with CI in the same manner as in Example 1.
Pigment Orange 36 was uniformly mixed to obtain a pigment composition of the present invention.

Example 8 4.8 parts of styrene, 4.0 parts of methacrylic acid and 109.7 parts of dimethylaminoethyl methacrylate are uniformly dispersed in 200 parts of methyl ethyl ketone, 7.4 parts of AIBN is added, and the mixture is gradually heated with stirring.

Further, the polymerization was completed at 65 ° C. or higher for 5 hours and then cooled to room temperature to obtain a copolymer solution containing 39% of the active ingredient. A pigment composition was obtained by uniformly mixing 5.1 parts of this copolymer with CI Pigment Orange 36 in the same manner as in Example 1.

Example 9 11.6 parts of hydroxyethyl methacrylate, 11.8 parts of methacrylic acid and dimethylaminoethyl methacrylate
Add 85.0 parts to 200 parts of methyl ethyl ketone and add AIBN7.4.
Parts were added and polymerization was carried out at 65 ° C. or higher for 5 hours to obtain a copolymer solution containing 34% of the active ingredient. 5.8 parts of this copolymer solution was uniformly mixed with CI Pigment Orange 36 in the same manner as in Example 1 to obtain a pigment composition of the present invention.

Example 10 8.4 parts of butyl methacrylate, 2.6 parts of methacrylic acid and 70 parts of dimethylaminoethyl methacrylate were dispersed in 128 parts of methyl ethyl ketone, 5 parts of AIBN was added, and polymerization was carried out at 65 ° C. or higher for 5 hours. The obtained polymer solution was cooled to room temperature to obtain a copolymer solution containing 39% of the active ingredient.

5.2 parts of the above copolymer solution was prepared in the same manner as in Example 1.
The pigment composition of the present invention was obtained by uniformly mixing with CI Pigment Orange 36.

Comparative Example 2 Pigment compositions of Examples 5-10 and CI Pigment 36 before treatment
Comparative tests were carried out in accordance with Example 4 using the above, and the results shown in Table 2 below were obtained.

Example 11 The copolymer solution obtained in Example 5 was uniformly mixed with the following pigment according to the method of Example 1 so that the active ingredient content was 5% to obtain a pigment composition of the present invention. Pigment 1; CI Pigment Yellow 109 pigment 2; CI Pigment Yellow 110 pigment 3; CI Pigment Yellow 123 pigment 4; CI Pigment Yellow 154 pigment 5; CI Pigment Yellow 173 pigment 6; CI Pigment Red 5 pigment 7; CI Pigment Red 178 pigment 8; CI Pigment Brown 25 Pigment 9; CI Pigment Violet 19 Pigment 10; CI Pigment Blue 15/3 Pigment 11; CI Pigment Green 7 Comparative Example 3 The pigment composition obtained in Example 11 was prepared according to Formulation 1 of Example 4. The results are shown in Table 3 below, which was made into a paint and compared with the corresponding untreated pigments.

Example 12 10 parts of CI Pigment Violet 19 were mixed with 26.4 parts of alkyd resin varnish (nonvolatile content 60%), 20 parts of xylol and 1.0 part of the copolymer obtained in Example 1 three times on a three-roll mill and kneaded. Then, the primary color base enamel was created. 30 parts of alkyd resin varnish (nonvolatile content 60%) and melamine resin varnish (nonvolatile content)
50%) was mixed well with 25 parts to prepare a primary color paint.

Comparative Example 4 CI prepared by the same method as in Example 12 except that the primary color paint obtained in Example 12 was not used in the copolymer obtained in Example 1.
Pigment Violet 19 primary color paint and the evaluation method of Comparative Example 1 were compared and evaluated, and the results shown in Table 4 below were obtained.

 ─────────────────────────────────────────────────── --- Continuation of the front page (56) Reference JP-A-60-81252 (JP, A) JP-A-60-81253 (JP, A) JP-A-60-123563 (JP, A) JP-A-60- 123564 (JP, A) JP-A-60-217271 (JP, A)

Claims (4)

[Claims] 1. A mixture of an organic pigment in the form of a solid, an aqueous paste or a slurry, and a solution of a solid (meth) acrylic acid-based polymer or a non-aqueous solvent thereof,
A pigment composition for dissolving and / or dispersing in an organic solvent, wherein the acrylic acid-based polymer is a polymer having the following monomer composition (a) and ratio (b). (A) (a) (meth) acrylic acid-based monomer represented by the following general formula (I) (b) (meth) acrylic acid (c) (a) and a monomer copolymerizable with (b) (b) The total amount of (a) and (b) is 85-100 in the total polymer.
% By weight, (c) is 0 to 15% by weight, and the weight ratio of (a) to (b) is 100 to (b) 3 to 20. (However, R ₁ in the above formula is H or CH ₃ , X is a C ₂ or more alkylene group which may have a hydroxyl group, and R ₂ and R ₃ may have a hydrogen atom or a hydroxyl group. A good alkyl group, but not a hydrogen atom at the same time.) 2. The pigment composition according to claim 1, wherein the (meth) acrylic acid-based polymer is present in an amount of 0.1 to 20% by weight per 100 parts by weight of the organic pigment. 3. The pigment composition according to claim 1, which is obtained by mixing the pigment and the solution and then removing the non-aqueous solvent. 4. The pigment composition according to claim 1, wherein the non-aqueous solvent is not removed after the pigment and the solution are mixed.