JP2665869B2 - Resin composition for pigment masterbatch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin composition for a pigment masterbatch. More specifically, pigment dispersibility is good, and room temperature drying alkyd, alkyd melamine,
The present invention relates to a resin composition suitable for producing a pigment masterbatch for a paint applicable to a very wide range of paint resins such as acrylic lacquer, acrylic melamine, acrylic urethane, vinyl acetate-acryl, and nitrified cotton lacquer.

[0002]

2. Description of the Related Art Conventionally, a pigment-containing paint or the like is prepared by mixing a pigment and a dispersing resin to prepare a pigment dispersion for a primary color paint (pigment masterbatch), and then forming a resin of the same kind as that used for the dispersion. It is diluted and commercialized. This is because when the pigment dispersing resin used for each pigment masterbatch and the resin used for dilution are different from each other, generally, the compatibility between the resins is poor, and the gloss and hardness of the coating film surface are reduced. This is because of its excellent compatibility with many kinds of paint resins.
It has been desired to develop a pigment dispersing resin that can be used commonly for various resin coatings. For this purpose, a method in which a urethane-modified polyester resin is used as a pigment dispersing resin (Japanese Patent Laid-Open No.
Japanese Patent Application Laid-Open No. 60-139712) and a method using a copolymer comprising butyl acrylate and a specific nitrogen-containing monomer as a resin for dispersing a pigment (Japanese Patent Application Laid-Open No. 60-139712).

[0003]

However, in the above method, the urethane-modified polyester resin has compatibility with a relatively wide range of resins, but has insufficient urethane resistance due to having urethane bonds, There is a problem that it cannot be used for paints that require weather resistance (paints for exterior use, etc.). In addition, copolymers composed of butyl acrylate and a specific nitrogen-containing monomer are limited in the types of compatible resins. Therefore, there is a problem that it cannot be used for a wide range of paints.

[0004]

DISCLOSURE OF THE INVENTION The present inventors have found that the present invention has a good compatibility with a very wide range of paint resins and, when mixed with each resin, includes the original properties of each resin paint including weather resistance. As a result of intensive studies on a resin for a pigment masterbatch that does not impair the performance and has excellent pigment dispersibility, the present invention has been achieved.

That is, the present invention relates to a pigment dispersing resin (A)
And a dispersant (B), wherein the (B) is a styrene-based monomer (a) 65-65.
A copolymer (B1) of a monomer comprising 100% by weight and an alkyl (meth) acrylate (C1-8) (b) 0-35% by weight, wherein (A) has a carbon number of 1-4. A resin for a pigment master batch, which is a copolymer (A1) of a (meth) acrylate (c) having an alkyl group of (c) and a (meth) acrylate (d) having an alkyl group having 6 to 30 carbon atoms. A composition.

In the present invention, examples of the styrene monomer (a) constituting (B1) include styrene and alkylstyrene (α-methylstyrene, p-methylstyrene, etc.). Of these, styrene is preferred.

Examples of the alkyl (meth) acrylate (b) include (meth) acrylates having an alkyl group having 1 to 8 carbon atoms. Specific examples of (b) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and a mixture of two or more of these.

In (B1), other than the above (a) and (b), if necessary, other polymerizable monomers may be copolymerized. Specific examples of other polymerizable monomers, for example,
(Meth) acrylates other than (b) [lauryl (meth)
Acrylate, stearyl (meth) acrylate, hydroxylethyl (meth) acrylate, hydroxyalkyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, (meth) acrylamide, (meth) acrylonitrile, (meth) Acrylic acid and the like can be mentioned. Of these, hydroxyethyl (meth) acrylate is preferred.

[0009] Of the monomers constituting (B1), the styrene monomer (a) is usually 65 to 100% by weight, preferably 70 to 95% by weight, and the alkyl (meth) acrylate (b) ) Is usually 0 to 35% by weight, preferably 5 to 3% by weight.
It is 0% by weight, and the other polymerizable monomer used as needed is usually 0 to 10% by weight, preferably 0 to 5% by weight.

The number average molecular weight of (B1) determined by gel permeation chromatography (GPC) is usually 1,0.
00 to 10,000, preferably 2,000 to
5,000. If it is less than 1,000, the physical properties of the coating film may be deteriorated. If it exceeds 10,000, the compatibility with various coating resins may be reduced.

The method for producing (B1) is not particularly limited. For example, a monomer mixture comprising (a) and (b) and optionally other polymerizable monomers may be prepared by known thermal polymerization, It can be produced by bulk or solution polymerization by a radical polymerization method such as photopolymerization or radiation polymerization. A preferred polymerization method is a radical solution polymerization method using a radical initiator in an organic solvent.

In the case of solution polymerization, examples of the organic solvent used include aromatic hydrocarbons such as toluene and xylene;
Aliphatic hydrocarbons such as heptane and mineral spirits,
Esters such as ethyl acetate and butyl acetate; ketones such as methyl ethyl ketone and methyl isobutyl ketone; ethers such as butyl cellosolve, butyl carbitol and ethylene glycol dimethyl ether; isopropanol;
Examples thereof include alcohols such as n-butanol and t-butanol and the like, and mixtures thereof. Among these, preferred solvents are toluene, xylene, methyl isobutyl ketone and butyl acetate alone or a mixture thereof.

When performing a radical polymerization reaction, azobisisobutyronitrile,
Examples include azo initiators such as azobisisovaleronitrile, and peroxides such as t-butyl peroxybenzoate, t-butyl peroxyisobutyrate, di-t-butyl peroxide, and hydrogen peroxide. Preferred among these are azobisisobutyronitrile, t-butylperoxybenzoate and t-butylperoxyisobutyrate.

In the method for producing the copolymer (B1), a known chain transfer agent such as lauryl mercaptan or dibenzyl ether may be used if necessary.

The polymerization temperature in the production of (B1) is usually 5
The temperature is 0 to 180 ° C., and the polymerization method may be either batch or continuous polymerization.

As the pigment dispersing resin (A) in the present invention, an alkyl (meth) acrylate (c) having an alkyl group having 1 to 4 carbon atoms and a (meth) acrylate having an alkyl group having 6 to 30 carbon atoms are used. A pigment dispersing resin comprising a copolymer (A1) of (d) and a polymerizable monomer (e) having a functional group is used. The resin has compatibility with various resins for coating materials and does not deteriorate the physical properties of the coating film.

In this case, (c) includes, for example, methyl (meth) acrylate, ethyl (meth) acrylate, 1-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl ( Examples thereof include (meth) acrylate, t-butyl (meth) acrylate, and a mixture of two or more thereof.

Of these, those which increase the glass transition point, ie, methyl (meth) acrylate, ethyl methacrylate,
Isobutyl methacrylate and t-butyl (meth)
Acrylates are preferred, and methyl methacrylate and t-butyl methacrylate are particularly preferred.

Examples of (d) include hexyl (meth) acrylate, cyclohexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, and dodecyl. (Meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, 1-methyltridecyl (meth) acrylate, hexadecyl (meth) acrylate, octadecyl (meth) acrylate, eicosyl (meth) acrylate, docosyl (meth) acrylate , Tetracosyl (meth) acrylate, triacontyl (meth) acrylate and mixtures of two or more of these.

Among these, hexyl (meth) acrylate, hexyl (meth) acrylate, and the like are preferable in order to be compatible with various kinds of coating resins and not to impair the original performance of each resin including weather resistance when mixed with each resin. Cyclohexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate and dodecyl (meth) acrylate are preferred.

Examples of the polymerizable monomer (e) having a functional group include a hydroxyl group-containing monomer (e1), a carboxylic acid-containing monomer (e2), and a nitrogen-containing monomer (e3). (E
Specific examples of 1) include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate,
Hydroxybutyl (meth) acrylate, 2,3-dihydroxypropyl (meth) acrylate, 3-chloro-
2-hydroxy (meth) acrylate and the like.
Of these, hydroxyethyl (meth) acrylate is particularly preferred.

Specific examples of (e2) include (meth) acrylic acid, (anhydride) maleic acid, fumaric acid, itaconic acid and the like, with (meth) acrylic acid being preferred.

Specific examples of (e3) include tertiary amino group-containing (meth) acrylates [dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate].
Acrylate, dimethylaminopropyl (meth) acrylate, diethylaminoethyl (meth) acrylate, etc.]; cyanoalkyl (meth) acrylates [cyanoethyl (meth) acrylate, etc.]; acrylonitrile, (meth) acrylamides [(meth) acrylamide, methyl ( (Meth) acrylamide, cyclohexyl (meth) acrylamide, dimethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, etc .; amine imide group-containing (meth) acrylates [trimethylamine (meth) acrylimide, dimethylethylamine (meth) acrylimide, Dimethylhydroxypropylamine (meth) acrylimide, dimethylphenylhydroxyethyl (meth) acrylimide, etc.]; quaternary ammonium Containing (meth) acrylates [(meth) acryloyloxyethyl trimethyl ammonium chloride, (meth) acryloyloxyethyl trimethyl ammonium methosulfate, etc.], and. Of these, preferred are (meth) acrylamides and (meth) acrylates containing an amine imide group, and particularly preferred is (meth) acrylamide.

The copolymer (A1) can be used as the above (c), (d)
If necessary, other than (e), a polymerizable monomer (f) may be copolymerized.

(F) is not particularly limited as long as it can be copolymerized with (c), (d) and (e). Specific examples include those other than (c), (d) and (e). (Meth) acrylates [pentyl (meth) acrylate, benzyl (meth) acrylate, dibromopropyl (meth) acrylate, isobornyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, allyl methacrylate, dicyclopentenyl (meth) acrylate, Dicyclopentanyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acryloxyethyl phosphate, caprolactone-modified-2-hydroxyethyl (meth) acrylate, 2-perfluorooctylethyl (meth) acrylate, γ- (meth) ) Acryloxypropyl tri (g) Methylsiloxy) silane, (meth) acrylsulfoethyl, etc.]; vinyl aromatic compounds (styrene, vinyltoluene, α-methylstyrene, etc.); vinyl chloride, vinyl acetate, butadiene, dicyclopentadiene, vinylpyrrolidone, isoprene, etc. No.

When (f) is used, the amount used is usually 30% by weight or less, preferably 20% by weight or less, based on all monomers in the copolymer (A1).

The weight ratio of (c) :( d) in the copolymer (A1) is usually (30-95) :( 5-70), preferably (45-90) :( 10-55). . If the ratio of (c) is less than 30, the compatibility with an acrylic resin, particularly an acrylic resin containing vinyl acetate, becomes insufficient, and
If it exceeds, the compatibility with the alkyd resin becomes extremely poor.

(C + d) :( e) is usually (40-98) :( 2-60), preferably (60-9), by weight.
5): (5 to 40). When the ratio of (e) is less than 2, the pigment dispersibility becomes insufficient, and when it exceeds 60, the compatibility of the alkyd resin becomes extremely poor.

As (e), usually, (e1) to (e)
It is at least one selected from the group of 3) and may be in the range of the above-mentioned weight ratio. However, in order to exhibit higher dispersibility for various pigments, it is necessary to use (e) as (e).
Those containing any of 1) to (e3) are more preferable. Further, the hydroxyl value of (A1) is 3 to 120 mgKOH.
/ G and an acid value of 0.005 to 50 mgKOH / g, preferably a hydroxyl value of 5 to 100 mgKOH / g and an acid value of 0.01 to 40 mgKOH / g.

The number average molecular weight determined by GPC of (A1) is as follows:
Usually 1,000 to 10,000, preferably 1,500
~ 8,000. If it is less than 1,000, the physical properties of the coating film are reduced. If it exceeds 10,000, the compatibility with various coating resins is reduced.

The method for producing (A1) is not particularly limited. For example, a monomer mixture comprising (c), (d), (e) and, if necessary, (f) may be prepared by known thermal polymerization, photopolymerization or It can be produced by bulk or solution polymerization by a radical polymerization method such as radiation polymerization. A preferred polymerization method is a radical solution polymerization method using a radical initiator in an organic solvent.

In the case of solution polymerization, examples of the organic solvent used include aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as heptane and mineral spirit; esters such as ethyl acetate and butyl acetate; Ketones such as methyl ethyl ketone and methyl isobutyl ketone; ethers such as butyl cellosolve, butyl carbitol and ethylene glycol dimethyl ether; alcohols such as isopropanol, n-butanol and t-butanol; and a mixture of two or more thereof. Among these, preferred solvents are toluene, xylene, methyl isobutyl ketone and butyl acetate alone or a mixture thereof.

When a radical polymerization reaction is carried out, azobisisobutyronitrile,
Examples include azo initiators such as azobisisovaleronitrile, and peroxides such as t-butyl peroxybenzoate, t-butyl peroxyisobutyrate, di-t-butyl peroxide, and hydrogen peroxide. Preferred among these are azobisisobutyronitrile, t-butylperoxybenzoate and t-butylperoxyisobutyrate.

In the production method (A1), a known chain transfer agent such as lauryl mercaptan or dibenzyl ether may be used if necessary.

The polymerization temperature in the production of (A1) is usually 5
The temperature is 0 to 180 ° C., and the method of polymerization may be either batch or continuous polymerization.

The pigment masterbatch resin composition of the present invention comprising the pigment dispersing resin (A) and the dispersant (B) is as follows:
(A) and (B) can also be obtained by a method of mixing after separately producing, but after producing (A) or (B), producing the other copolymer in the presence of the copolymer Can also be obtained.

The resin composition for a pigment masterbatch of the present invention comprises a resin (A) for dispersing a pigment and a dispersant (B) as essential components, and if necessary, an organic solvent, another resin for a paint, or a resin for various paints. Additives (surfactant, fluidity modifier, pigment dispersant, adhesion improver, etc.) and the like may be blended.

The pigment masterbatch comprises the resin composition of the present invention, a pigment, and, if necessary, an organic solvent, another resin for paint,
Alternatively, it can be obtained by blending various paint additives and the like. The pigment concentration in this case varies depending on the kind of the pigment, but is usually 10 to 60% by weight.

As the organic solvent, those exemplified above as the solvent for polymerization can be used.

Examples of the pigment include inorganic pigments (carbon black, iron oxide, titanium oxide, calcium carbonate, graphite, zinc white, dark blue, etc.) and organic pigments (nitroso pigment, nitro pigment, azo pigment, phthalocyanine pigment, etc.). And mixtures thereof.

The compound of the resin composition for pigment dispersion of the present invention or the pigment masterbatch for paint using the same can be prepared by using a conventional disperser such as a roll mill disperser, a sand grind mill disperser, a planetary mixer, a high speed It is obtained by mixing and dispersing in a usual manner using a disperser or the like.

[0042]

EXAMPLES The present invention will be further described with reference to the following examples, but the present invention is not limited to these examples. Parts in the examples are parts by weight.

[Production of Dispersant (B)] Production Example 1 30 parts of methyl isobutyl ketone and 70 parts of xylene were placed in a flask equipped with a stirrer, a condenser, a thermometer, an inert gas inlet tube and a dropping pump. Gas is introduced to reflux methyl isobutyl ketone (temperature;
After that, a mixture of 75 parts of styrene, 22 parts of butyl methacrylate, 3 parts of hydroxyethyl acrylate and 5 parts of t-butyl peroxoisobutyrate was added dropwise with stirring over 3 hours. Add 2.5 parts of oxyisobutyrate over 1.5 hours,
The mixture was further reacted at the same temperature for 1 hour to obtain a dispersant solution 1 having a nonvolatile content of 50% and a number average molecular weight of 4,600 (by GPC; the same applies hereinafter).

Production Example 2 In Production Example 1, 80 parts of styrene was used instead of 75 parts.
Parts, 17 parts butyl methacrylate instead of 22 parts,
Dispersant solution 2 having a nonvolatile content of 50% and a number average molecular weight of 2,600 was obtained in the same manner as in Production Example 1, except that 7.5 parts of t-butyl peroxoisobutyrate was used instead of 5 parts. .

Production Example 3 In Production Example 1, 90 parts of styrene was used instead of 75 parts.
Part, butyl methacrylate 22 parts, 2-ethylhexyl methacrylate 7 parts, and t-butyl peroxoisobutyrate 6 parts instead of 5 parts, in the same manner as in Production Example 1 except that the nonvolatile content was 50%. A dispersant solution 3 having a number average molecular weight of 3,600 was obtained.

[Production of Pigment Dispersion Resin (A)] Production Example 4 30 parts of methyl isobutyl ketone and 70 parts of xylene were placed in a flask equipped with a stirrer, a condenser, a thermometer, an inert gas inlet tube and a dropping pump. An inert gas is introduced to reflux methyl isobutyl ketone (temperature: 114 to 1).
18 ° C.) and then, with stirring, methyl methacrylate 67.5.
, 25 parts of octyl methacrylate, 0.5 parts of maleic anhydride, 3 parts of hydroxyethyl acrylate, 4 parts of cyclohexyl methacrylate and 5 parts of t-butyl peroxyisobutyrate were added dropwise over 3 hours. 2.5 parts of t-butyl peroxyisobutyrate was added over 1.5 hours, and the mixture was further reacted at the same temperature for 1 hour to obtain a resin solution 1 for pigment dispersion having a nonvolatile content of 50% and a number average molecular weight of 5,600. I got

Examples 1-3 and Comparative Example 1 The dispersant solution 1 obtained in Production Example 1 and the resin solution 1 for pigment dispersant obtained in Production Example 4 have a solid content weight ratio of 5:95. Composition 1 for pigment masterbatch
I got Similarly, a pigment masterbatch resin composition 2 is prepared from the dispersant solution 2 and the pigment dispersant resin solution 1, and a pigment masterbatch resin composition 3 is prepared from the dispersant solution and the pigment dispersant resin solution 1. Obtained. The resin solution 1 for a pigment dispersant was used as a resin composition 4 for a comparative master batch (Comparative Example 1).

To 20 parts of each of the obtained pigment masterbatch resin compositions 1 to 4, 60 parts of titanium oxide, 10 parts of xylene and 10 parts of propylene glycol monomethyl ether monoacetate were mixed, and the mixture was mixed with a sand grinding mill disperser. The pigment master batches [1] to [4] were dispersed until the particle size became 10 μm or less.

Performance test Pigment master batches [1] to [4], melamine / alkyd varnish @ melamine resin varnish [Melan # 28 manufactured by Hitachi Chemical Co., Ltd.] and 30% oil-length soybean oil-modified trimethylolpropane / phthalic acid Mixed varnish having a solid content weight ratio of 2/8 with varnish (non-volatile content: 50%)} and melamine / acrylic varnish {melamine resin varnish [Melan # 28 manufactured by Hitachi Chemical Co., Ltd.] and acrylic resin A (methyl methacrylate 60 parts) , A varnish mixed with a copolymer having a monomer composition of 28 parts of butyl acrylate, 10 parts of hydroxyethyl acrylate and 2 parts of acrylic acid, having a number average molecular weight of about 15,000, and having a solid content weight ratio of 2/8 (nonvolatile content: 50% )｝
Were mixed so that the resin solid content weight ratio was 5/5, to obtain white paints A1 to A4 from melamine / alkyd varnish and white paints B1 to B4 from melamine / acrylic varnish. After diluting each white paint with a mixed thinner, the paint was spray-coated on a treated steel sheet so that the dry film thickness became 30 μm, and the coating film performance after baking at 140 ° C. for 20 minutes was evaluated. Table 1 shows the results.

[0050]

[Table 1] 1) JIS K-5400 67; 60 degree specular reflectance 2) JIS K-5400 614; use Mitsubishi Uni pencil

[0051]

The resin composition for a pigment masterbatch of the present invention has excellent pigment dispersibility for various pigments and shows good compatibility with various paint resins, so that it is commonly used for various paint resins. It becomes possible to produce a pigment master batch that can be produced. Pigment master batch using the composition of the present invention,
Room temperature drying type alkyd paint, alkyd melamine paint, acrylic lacquer paint, acrylic melamine paint, vinyl acetate paint, nitrified cotton lacquer paint can be used as a coloring agent for a very wide range of paints. It greatly reduces the number of types and improves paint productivity.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location C09D 133/06 PGF C09D 133/06 PGF // C08L 101: 00 Examiner Satoshi Morikawa (56) References JP-A-63-146935 (JP, A)

Claims (4)

(57) [Claims] 1. A pigment dispersing resin composition for paints comprising a pigment dispersing resin (A) and a dispersant (B), wherein (B) is 65 to 100% by weight of a styrene monomer (a) and (B) Alkyl (meth) acrylate (C1-8)
(B) a (co) polymer (B1) of a monomer comprising 0 to 35% by weight, wherein (A) is a (meth) acrylate (c) having an alkyl group having 1 to 4 carbon atoms, and 6 ~
(Meth) acrylate having 30 alkyl groups (d)
A resin composition for a pigment masterbatch, characterized in that it is a copolymer (A1). 2. The resin composition according to claim 1, wherein (B) has a number average molecular weight of 1,000 to 10,000. 3. The weight ratio of (A) :( B) is (70-9)
9.5): The resin composition according to claim 1 or 2, wherein (0.5 to 30). 4. The resin composition according to claim 1, which is used in a non-aqueous system.