JP2002206013A - Pigment-dispersed resin and water-based pigment dispersion including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pigment-dispersed resin that shows a low viscosity and excellent color development, even when the pigment concentration is high, and can provide a water-based pigment dispersion capable of giving excellent finish appearance of the film layer with excellent coating performance. SOLUTION: In the presence of a metal complex as a catalytic chain transfer agent or an additional cleavage type chain transfer agent, methacrylic acid and at least one copolymerizable monomer selected from a methacrylate ester and styrene are copolymerized to prepare a macromonomer (A). The macromonomer (A) and an epoxy group-bearing polymerizable unsaturated compound (E) are subjected to esterification reaction to prepare a polymerizable unsaturated group-bearing macromonomer (A-1). Then, the resultant macromonomer (A-1) is copolymerized together with (B) a polymerizable unsaturated monomer bearing amino group, quaternary ammonium base or sulfonic acid group-bearing, (C) a polymerizable unsaturated monomer bearing polyoxyalkylene chain and (D) other unsaturated monomers to produce the objective pigment-dispersed resin having a weight-average molecular weight of 3,000-100,000 and a resin acid value of 10-200 mg KOH.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pigment-dispersed resin which can be suitably applied to a water-based paint, particularly a water-based topcoat for automotive coating, a water-based pigment dispersion containing the pigment-dispersed resin, and a water-based paint composition.

[0002]

2. Description of the Related Art Heretofore, as a top coat for automotive coating, a base resin (base polymer) component such as an acrylic resin, a polyester resin, and an alkyd resin having a functional group such as a hydroxyl group and a carboxyl group, an amino resin, Solvent-type ones using a curing agent such as a polyisocyanate compound or an epoxy compound which may be blocked have been widely used.

[0003] In recent years, from the viewpoint of protection of the global environment, paints having a low volatile organic content (VOC) have been demanded. In the field of paints for automotive coatings, in particular, paints for coloring base coats have a large amount of discharged VOCs, and there is a strong demand for water-based coatings. In the future, the switch from solvent-based base coats to water-based base coats is expected to proceed.

[0004] Problems associated with water-based coloring of base coat paints include, for example, (1) that the pigment-dispersed resin blended in the water-based paint is not compatible with the binder component in the water-based paint; The pigment is not uniformly dispersed by the dispersing resin or the dispersing agent, and the pigment causes aggregation (flocculation or agglomeration). (3) The pigment dispersing resin or the dispersing agent in the aqueous paint is applied without being cured by baking. And deterioration of film performance.

In designing a pigment-dispersed resin in an aqueous paint, the surface of the pigment is hydrophobic, so that the pigment is hardly wetted by water, which is the main dispersion medium. It has the characteristic that it tends to cause a decrease in stability, and it is considered important to achieve both the wettability of the pigment and the dispersion stability of the pigment dispersion resin in the dispersion medium.

With respect to the wettability of the pigment, it is advantageous that the pigment-dispersed resin has a low viscosity and a low molecular weight. Regarding the dispersion stabilization, the formation of a steric repulsion layer on the pigment surface and the continuous phase of the pigment-dispersed resin are considered. It is said that good solubility in (aqueous medium) is advantageous. In addition, wetting of the pigment-dispersed resin on the pigment surface due to the interaction between the hydrophobic portion of the pigment surface and the hydrophobic portion of the pigment-dispersed resin (the pigment-dispersed resin having an aqueous group such as an alkyl group that causes weak aggregation in an aqueous system is effective) It is considered that the adsorption to the pigment and the pigment is related to both the wettability of the pigment and the dispersion stability of the pigment dispersion resin.

From the above viewpoints, pigment dispersion resins and auxiliaries for water-based paints have been developed. For example, JP
JP-A-154328, etc., have an acidic functional group obtained by polymerizing a monomer mixture containing an acidic functional group-containing polymerizable unsaturated monomer such as (meth) acrylic acid as a part of a monomer component. Although linear anionic polymers are known, these resins are not sufficient in terms of stabilizing the dispersion of the pigment dispersion because the resin itself has solubility in an aqueous medium, and the dispersion is remarkable. There is a problem that the viscosity is high and handling becomes difficult.

[0008] Japanese Patent Application Laid-Open Nos. 1-182304, 7-316240, and 10-5020297
As described in Japanese Patent Application Laid-Open Publication No. H10-264, a graft copolymer obtained by copolymerizing a carboxyl group-containing macromonomer is also known. These graft copolymers are excellent in the dispersion stabilization of the pigment dispersion because the trunk portion of the polymer is hydrophobic and the branch portion is hydrophilic, but the viscosity of the pigment dispersion is high. In the future, a pigment dispersion having an even higher pigment concentration is required from the viewpoint of cost and VOC reduction, so that these graft copolymers are never satisfactory.

At the present time, topcoats for automotive coatings have not only high coating durability such as high durability, acid resistance, car wash abrasion resistance and chipping resistance, but also sharpness and transparency more than before. There is a demand for a finished appearance of the coating film such as color development.

An object of the present invention is to overcome the above-mentioned problems relating to the finished appearance of a coating film, and to provide an aqueous solution having excellent wettability and dispersion stability, low viscosity and excellent color development even at a high pigment concentration. An object of the present invention is to provide a pigment dispersion resin capable of obtaining a pigment dispersion. Another object of the present invention is to obtain an aqueous pigment dispersion having a low viscosity and excellent color development. It is a further object of the present invention to provide a water-based paint which is excellent in curability and can form a coating film having excellent finish appearance such as sharpness, transparency, and coloring.

[0011]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, have found that a specific monomer component can be obtained in the presence of a metal complex as a catalytic chain transfer agent and a radical polymerization initiator. Using a macromonomer having a polymerizable unsaturated group introduced by an esterification reaction into a high acid value macromonomer obtained by copolymerizing the polymerizable monomer with the ionic hydrophilic functional group and an ionic hydrophilic functional group. The inventors have found that the above object can be achieved by using a pigment dispersion resin which is a copolymer into which an ionic functional group has been introduced, and have completed the present invention.

That is, the present invention provides a method for preparing a methacrylic acid, a methacrylic acid ester and styrene in the presence of a metal complex or an addition-cleaving type chain transfer agent as a catalytic chain transfer agent and, if necessary, a radical polymerization initiator. An epoxy group-containing polymerizable unsaturated compound (E) is esterified with a carboxyl group-containing macromonomer (A) having a resin acid value of 50 to 450 mgKOH / g obtained by copolymerizing at least one type of copolymerizable monomer. A polymerizable unsaturated group-containing macromonomer (A-1), an amino group,
Polymerizable unsaturated monomer (B) containing at least one ionic functional group selected from quaternary ammonium bases and sulfonic acid groups, nonionic polymerizable unsaturated monomer having a polyoxyalkylene chain (C) and others The weight average molecular weight obtained by copolymerizing a monomer mixture comprising an ethylenically unsaturated monomer (D) in the presence of a radical polymerization initiator is 3,000 to 100,000,
Another object of the present invention is to provide a pigment-dispersed resin having a resin acid value in the range of 10 to 200 mgKOH / g (hereinafter referred to as “pigment-dispersed resin (I)”).

The present invention also provides a polymerizable unsaturated group-containing macromonomer (A-1), a polymerizable polymer containing at least one ionic functional group selected from an amino group, a quaternary ammonium base and a sulfonic acid group. Unsaturated monomer (B),
A copolymer obtained by copolymerizing a monomer mixture comprising a nonionic polymerizable unsaturated monomer (C) having a polyoxyalkylene chain and another ethylenically unsaturated monomer (D) in the presence of a radical polymerization initiator. The weight average molecular weight obtained by reacting the long chain alkyl group by reacting the epoxy group-containing long chain alkyl compound (F) with the union (K) is 3,000 to 100,000, and the resin acid value is 10 The present invention provides a pigment-dispersed resin (hereinafter, referred to as “pigment-dispersed resin (II)”) in a range of from 200 mgKOH / g.

Further, the present invention provides a long-chain obtained by reacting the carboxyl-containing macromonomer (A) with an epoxy-containing polymerizable unsaturated compound (E) and an epoxy-containing long-chain alkyl compound (F). A polymerizable unsaturated monomer (B) containing at least one ionic functional group selected from an alkyl group and a polymerizable unsaturated group-containing macromonomer (A-2), an amino group, a quaternary ammonium base and a sulfonic acid group; , A weight obtained by copolymerizing a monomer mixture comprising a nonionic polymerizable unsaturated monomer (C) having a polyoxyalkylene chain and another ethylenically unsaturated monomer (D) in the presence of a radical polymerization initiator. Average molecular weight of 3,000-100,0
And a resin dispersion having a resin acid value of 10 to 200 mgKOH / g (hereinafter referred to as “pigment dispersion resin (II
I) ”).

Further, the present invention provides the above-mentioned pigment-dispersed resin, pigment,
An object of the present invention is to provide an aqueous pigment dispersion containing an aqueous medium, a basic neutralizing agent and, if necessary, a dispersing aid.

Further, the present invention provides an aqueous coating composition containing the above aqueous pigment dispersion. Hereinafter, the present invention will be described in detail.

[0017]

First, the pigment-dispersed resin of the present invention will be described.

Pigment-dispersed resin (I) : The pigment-dispersed resin (I) of the present invention comprises the following polymerizable unsaturated group-containing macromonomer (A-1) and an ionic functional group-containing polymerizable unsaturated monomer ( B), obtained by copolymerizing a nonionic polymerizable unsaturated monomer (C) containing a polyoxyalkylene chain and another ethylenically unsaturated monomer (D).

The polymerizable unsaturated group-containing macromonomer (A-
1) : Macromonomer containing a polymerizable unsaturated group (A-1)
Can be obtained by subjecting the following carboxyl group-containing macromonomer (A) to an esterification reaction of an epoxy group-containing polymerizable unsaturated compound (E).

Carboxyl group-containing macromonomer (A)
Is at least one polymerizable monomer selected from methacrylate and styrene in the presence of a metal complex or an addition-cleavable chain transfer agent which is a catalytic chain transfer agent and, if necessary, a radical polymerization initiator; It is a copolymer having a polymerizable unsaturated group obtained by polymerizing a monomer component composed of methacrylic acid.

When the copolymerization reaction is carried out in the presence of the above catalytic chain transfer agent, catalytic chain transfer polymerization (catalytic Ch
The copolymerization reaction is performed by ain Transfer Polymerization (CCTP method).

Regarding the CCTP method, for example,
No. 23209, Japanese Patent Publication No. 7-35411, Japanese Patent Publication No. 9-501457, Japanese Patent Application Laid-Open No. 9-176256, Macromolecules, 1996, 2
9,8083 to 8089, etc., and in the present invention, the macromonomer (A) can
It can be obtained using the CTP method. That is, when performing a catalytic chain transfer polymerization, a polymerizable unsaturated monomer is prepared by subjecting a polymerizable unsaturated monomer to a solution polymerization method in an organic solvent in water in the presence of a metal complex as a catalytic chain transfer agent and a radical polymerization initiator. Catalytic chain transfer polymerization can be carried out by a method such as emulsion polymerization.

Examples of the metal complex used in the copolymerization include a cobalt complex, an iron complex, a nickel complex,
Examples thereof include a ruthenium complex, a rhodium complex, a palladium complex, a rhenium complex, and an iridium complex. Of these, a cobalt complex is preferable because it efficiently acts as a catalytic chain transfer agent.

Examples of such a cobalt complex include, for example, Japanese Patent Publication No. 6-23209, Japanese Patent Publication No. 7-35411, US Pat. No. 4,526,945, US Pat.
USP4837326, USP4888661, USP
5324879, WO95 / 17435, Tokiohei 9-5
Known ones described in, for example, Japanese Patent No. 10499 can be used. Specific examples include bis (borondifluorodioxyiminocyclohexane) Co (II), bis (1,2-dioxyiminoethane) Co (II), and bis (borondifluorodimethylglyoxymate) Co (I
I), bis (borondifluorodiphenylglyoximate) Co (II), a cobalt (II) chelate of a bicinaliminohydroxyimino compound, a cobalt (II) chelate of a diazadihydroxyiminodialkyldecadiene,
Cobalt (II) chelate of diazadihydroxyiminodialkyldecadiene, cobalt (II) chelate of diazadihydroxyiminodialkylundecadiene, cobalt (II) chelate of tetraazatetraalkylcyclotetradecatetraene, tetraazatetraalkylcyclo A cobalt (II) chelate of tetradodecattraene,
Cobalt (II) chelate of N, N'-bis (salicylidene) ethylenediamine, cobalt (II) chelate of dialkyldiazadioxodialkyldodecadiene, cobalt (II) chelate of dialkyldiazadioxodialkyltridecadiene, cobalt (II) Porphyrin complexes and the like can be mentioned. Of these, bis (borondifluorodimethylglyoxymate) Co (II) and bis (borondifluorodiphenylglyoxymate) Co (II), which are particularly easily available, can be preferably used.

Further, for example, a metal complex described in JP-B-8-19172, in which a radical cleavable group is directly bonded to a metal, can be used as the metal complex. Examples of the metal include cobalt, rhenium, and iridium, and examples of the group that can undergo radical cleavage include an alkyl group, an aryl group, and a heterocyclic group. In a system using a metal complex in which a radical cleavable group is directly bonded to the metal, a radical polymerization initiator may not be used in combination.

The amount of the metal complex which is a catalytic chain transfer agent is not particularly limited, but is usually methacrylic acid and at least one copolymerizable monomer selected from methacrylic acid esters and styrene. Total amount of 10
Based on 0 parts by weight, it is suitable that the amount is usually 1 × 10 ⁻⁶ to 1 part by weight, preferably 1 × 10 ^{−4 to} 0.5 part by weight.

In order to adjust the reactivity of the metal complex and improve the solubility, a known coordination compound may be added as necessary. Examples of such coordination compounds include phosphorus compounds such as triphenylphosphine and tributylphosphine; and amine compounds such as pyridine and tributylamine.

As the polymerization initiator usable in the CCTP method, for example, cyclohexanone peroxide, 3,3,
Ketone peroxides such as 5-trimethylcyclohexanone peroxide and methylcyclohexanone peroxide; 1,1-bis (tert-butylperoxy)-
Peroxyketals such as 3,3,5-trimethylcyclohexane, 1,1-bis (tert-butylperoxy) cyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate; cumene hydropar Hydroperoxides such as oxide and 2,5-dimethylhexane-2,5-dihydroperoxide;
3-bis (tert-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (tert-
Butylperoxy) hexane, diisopropylbenzene peroxide, dialkyl peroxides such as tert-butylcumyl peroxide; diacyl peroxides such as decanoyl peroxide, lauroyl peroxide, benzoyl peroxide and 2,4-dichlorobenzoyl peroxide. Peroxycarbonates such as bis (tert-butylcyclohexyl) peroxydicarbonate; peroxyesters such as tert-butylperoxybenzoate and 2,5-dimethyl-2,5-di (benzoylperoxy) hexane Organic peroxide-based polymerization initiators such as 2,2'-azobisisobutyronitrile, 1,1-azobis (cyclohexane-1-carbonitrile), azocumene 2,2'-azobismethylvaleronitrile, , 4 ' It can be mentioned azo polymerization initiator such as azobis (4-cyanovaleric acid). The use amount of these radical polymerization initiators is not particularly limited, but usually, the total amount of the copolymerizable monomers is 100.
0.1 to 15 parts by weight, especially 0.3 to 8 parts by weight, based on parts by weight
Desirably it is in the range of parts by weight.

The macromonomer (A) can also be produced using an addition-cleavable chain transfer agent. When an addition-cleavable chain transfer agent is used, a copolymerization reaction is carried out by radical addition-cleavage chain transfer polymerization. Examples of the addition-cleavable chain transfer agent include 2,4-diphenyl-4-methyl-1-pentene (“α-methylstyrene dimer”).
, Etc.). The blending amount of the addition-cleavable chain transfer agent is not particularly limited, but based on 100 parts by weight of the total amount of the copolymerizable monomer,
Usually, it is appropriate that the amount is in the range of 1 to 50 parts by weight, preferably 5 to 30 parts by weight.

In the case of performing radical addition-fragmentation type chain transfer polymerization, a polymerizable unsaturated monomer is prepared by a solution polymerization method in an organic solvent in the presence of an addition-fragmentation-type chain transfer agent and a radical polymerization initiator. Chain transfer polymerization can be carried out by a method such as an emulsion polymerization method. As the radical polymerization initiator, those exemplified as the polymerization initiator that can be used in the CCTP method can be similarly used.

The macromonomer (A) contains methacrylic acid and at least one copolymerizable monomer selected from methacrylic acid esters and styrene as constituent monomer components. Specific examples of the methacrylate include, for example, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate,
C1 such as -ethylhexyl methacrylate, n-octyl methacrylate, lauryl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, tridecyl methacrylate, etc.
-24 or cyclic alkyl methacrylate monomer; 2
-Hydroxyalkyl methacrylates such as hydroxyethyl methacrylate, hydroxypropyl methacrylate, 2,3-dihydroxybutyl methacrylate and 4-hydroxybutyl methacrylate, and monoesters of polyhydric alcohols such as polyethylene glycol monomethacrylate with acrylic acid or methacrylic acid monster,
Hydroxyl-containing polymerizable unsaturated monomers such as compounds obtained by ring-opening polymerization of ε-caprolactone to the monoesterified product of the above polyhydric alcohol and methacrylic acid; N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, N Aminoalkyl methacrylates such as N, N-dimethylaminopropyl methacrylate; 3
Oxetane ring-containing methacrylates such as -ethyl-3-methacryloyloxymethyl oxetane, 3-methyl-3-methacryloyloxymethyl oxetane, and 3-butyl-3-methacryloyloxymethyl oxetane. These polymerizable unsaturated monomers can be used alone or in combination of two or more.

The ratio of methacrylic acid to at least one copolymerizable monomer selected from methacrylic acid esters and styrene is such that the resulting macromonomer has an acid value of 50.
~ 450mgKOH / g, preferably 65 ~ 400mg
KOH / g, particularly preferably 65 to 325 mg KOH / g
g, and based on the total amount of the monomer components, the methacrylic acid content is usually 8 to 70% by weight, preferably 10 to 60% by weight, particularly preferably 10 to 50% by weight. The polymerizable monomer is in the range from 30 to 92% by weight, preferably from 40 to 90% by weight, particularly preferably from 50 to 90% by weight.

Examples of the polymerization method for obtaining the macromonomer (A) include a solution polymerization method in an organic solvent and an emulsion polymerization method in water, as described above. Legitimate is preferred. The solution polymerization method includes, for example, the above monomer component (methacrylic acid and at least one copolymerizable monomer selected from methacrylic acid ester and styrene), the above-mentioned metal complex which is the catalytic chain transfer agent, or the addition cleavage type. A chain transfer agent and, if necessary, a radical polymerization initiator are dissolved or dispersed in an organic solvent.
A method in which the copolymerization is carried out by heating at a temperature of about 1 ° C. while stirring usually for about 1 to 10 hours.

Examples of the organic solvent include hydrocarbon solvents such as heptane, toluene, xylene, octane and mineral spirit; ethyl acetate, n-butyl acetate;
Ester solvents such as isobutyl acetate, ethylene glycol monomethyl ether acetate and diethylene glycol monobutyl ether acetate; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone and cyclohexanone; methanol, ethanol, isopropanol, n-butanol, sec-butanol, iso- Alcohol solvents such as butanol; ethers such as n-butyl ether, dioxane, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether; swazole 310 manufactured by Cosmo Oil;
Examples thereof include aromatic petroleum solvents such as Swazole 1000 and Swazole 1500. These organic solvents can be used alone or in combination of two or more.
At the time of copolymerization, the organic solvent is used in an amount of usually 400 parts by weight or less based on the total amount of the copolymerized monomer components.

In the above copolymerization reaction, the method of adding the polymerization component and the polymerization initiator is not particularly limited, but the polymerization initiator is divided into several times from the initial stage of the polymerization to the latter stage of the polymerization, rather than being charged all at once in the early stage of the polymerization. Separation and dropping are preferred from the viewpoint of controlling the temperature in the polymerization reaction, suppressing the formation of poor crosslinked products such as gelled products, and the like.

The macromonomer (A) thus obtained has at least one polymerizable unsaturated bond at one end of its molecule, preferably one polymerizable unsaturated bond, and is dispersed in water. The acid value of the resin is 50 to 45 in terms of stability, pigment dispersibility, viscosity, VOC, and the number of colors (degree of coloring) of the resin.
0 mgKOH / g, preferably 65-400 mgKOH
/ G, particularly preferably in the range of 65 to 325 mg KOH / g, and the molecular weight is not particularly limited,
Usually, the weight average molecular weight is 300 to 15,000, preferably 500 to 10,000, particularly preferably 500 to 10,000.
It is preferably in the range of 7,000.

The above-mentioned macromonomer (A) is subjected to an esterification reaction to give a polymerizable unsaturated group-containing macromonomer (A-
As the epoxy group-containing polymerizable unsaturated compound (E) used for obtaining 1), glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth)
Acrylate, β-methylglycidyl (meth) acrylate and the like can be mentioned, and among them, glycidyl methacrylate is preferable.

In the above esterification reaction, the mixing ratio of the macromonomer (A) and the epoxy group-containing polymerizable unsaturated compound (E) depends on the molecular weight of the obtained pigment dispersion resin and the obtained macromonomer (A-1). ) And another monomer component, the resin can be produced stably without a problem of remarkable thickening or gelling of the resin at the time of the copolymerization reaction of the macromonomer (A). The content of the polymerizable unsaturated compound (E) is preferably 0.5 to 15 parts by weight, more preferably 1.0 to 10 parts by weight.
Parts by weight. This esterification reaction introduces a polymerizable unsaturated group. In the resulting polymerizable unsaturated group-containing macromonomer (A-1), the amount of the polymerizable unsaturated group introduced by esterification is set to 0.1 based on the polymerizable unsaturated group-containing macromonomer (A-1). 005-2.5 mol / kg, preferably 0.01-2.0 mol / kg, particularly preferably 0.01-1.6 mol / kg.

In the above esterification reaction, an organic solvent is added as required, and usually at a reaction temperature of about 100 ° C. to 150 ° C., the macromonomer (A) and the epoxy group-containing polymerizable unsaturated compound (E) are reacted. Is reacted. At that time, it is preferable to use a tertiary amine such as N, N-dimethyllaurylamine or N, N-dimethyldodecylamine as a catalyst, and to use a polymerization inhibitor such as 4-t-butylpyrocatechol in combination.

Polymerizable unsaturated monomers containing ionic functional groups
Nomer (B) Polymerizable unsaturated monomer containing an ionic functional group (B)
Is a polymerizable unsaturated monomer containing at least one ionic functional group selected from an amino group, preferably a tertiary amino group, a quaternary ammonium base and a sulfonic acid group.

Specific examples of such a monomer (B) include, for example, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) Aminoalkyl (meth) acrylates containing an N, N-dialkylamino group such as acrylate, N, N-di-t-butylaminoethyl (meth) acrylate, N, N-dimethylaminobutyl (meth) acrylate; methacryloyloxyethyl Quaternary ammonium base-containing polymerizable unsaturated monomers represented by (meth) acryloyloxyalkyltrialkylammonium halides such as trimethylammonium chloride; (meth) acrylamides such as 2-acrylamido-2-methylpropanesulfonic acid Al Sulfonic acid group-containing polymerizable unsaturated monomer represented by Nsuruhon acid.

Of these, N, N-dimethylaminoethyl (meth) acrylate, methacryloyloxyethyltrimethylammonium chloride and 2-acrylamido-2-methylpropanesulfonic acid are particularly preferred.

Nonionic polymerizable unsaturated monomer (C) The monomer (C) is a nonionic polymerizable unsaturated monomer having a polyoxyalkylene chain, and includes a compound represented by the following formula. During ^{_{CH 2 = C (R 1)}} COO (C n H 2n O) m -R 2 Formula, ^{R 1} represents a hydrogen atom or CH _3, ^{R 2} represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms , M is 4-6
0, especially an integer from 4 to 55, and n is an integer from 2 to 3, wherein m oxyalkylene units (C _n H _2n
O) may be the same or different from each other.

Specific examples of such a monomer (C) include, for example, tetraethylene glycol (meth) acrylate, methoxytetraethylene glycol (meth) acrylate, ethoxytetraethylene glycol (meth) acrylate, n-butoxytetraethylene glycol (Meth) acrylate, tetrapropylene glycol (meth) acrylate, methoxytetrapropylene glycol (meth) acrylate, ethoxytetrapropylene glycol (meth) acrylate, n-butoxytetrapropylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene Glycol (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, ethoxy polyethylene glycol Meth) acrylate, and the like. Of these, polyethylene glycol (meth) acrylate and polypropylene glycol (meth) acrylate are particularly preferred.

Other Ethylenically Unsaturated Monomer (D) The other ethylenically unsaturated monomer (D) is a polymerizable unsaturated monomer other than the above-mentioned monomers (B) and (C). Is a monomer that is appropriately selected and used in accordance with the properties desired for the polymer.

As such a monomer (D), for example, methacrylic acid ester and / or styrene can be suitably used. As the methacrylic acid ester, the same methacrylic acid ester used for producing the macromonomer (A) can be used. However, as the monomer (D) component, in addition to at least one monomer selected from methacrylic acid esters and styrene, a quantitative ratio of up to 30% by weight of the monomer (D) other than methacrylic acid esters and styrene Can be used in combination.

Examples of the other monomers include, for example,
C such as methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, etc.
Hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate; N, N-dimethylaminoethyl acrylate;
Aminoalkyl acrylates such as N-diethylaminoethyl acrylate and N, N-dimethylaminopropyl acrylate; acrylamide, N, N-dimethylaminoethyl acrylamide, N, N-diethylaminoethyl acrylamide, N-methylol acrylamide methyl ether, N-methylol acrylamide Acrylamide such as butyl ether or a derivative thereof; oxetane ring-containing acrylate such as 3-ethyl-3-acryloyloxymethyloxetane and 3-methyl-3-acryloyloxymethyloxetane; carboxyl group-containing polymerizable unsaturated monomer such as acrylic acid; acrylonitrile And vinyl toluene. These monomers can be used alone or in combination of two or more.

Since the pigment-dispersed resin provided by the present invention is mainly used for preparing a paint for a colored aqueous base coat, it reacts with a curing agent component, for example, an amino resin or a polyisocyanate compound which may be blocked to form a cross-linked coating. Incorporation into the film is desirable from the viewpoint of coating film performance. Therefore, it is desirable that the monomer (D) component contains a hydroxyl group-containing polymerizable unsaturated monomer.

Specific examples of the hydroxyl group-containing polymerizable unsaturated monomer include, for example, 2-hydroxyethyl (meth)
Of polyhydric alcohols such as acrylate, hydroxypropyl (meth) acrylate, 2,3-dihydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and polyethylene glycol mono (meth) acrylate with acrylic acid or methacrylic acid Monoesters: Compounds obtained by ring-opening polymerization of ε-caprolactone with monoesters of the above polyhydric alcohol and acrylic acid or methacrylic acid, and the like can be mentioned. Among them, 4-hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate [other than the monomer (C)], and ε-caprolactone are used as monoesters of polyhydric alcohol and acrylic acid or methacrylic acid. A compound obtained by ring-opening polymerization is preferred in terms of reactivity and the like. These compounds can be used alone or in combination of two or more.

The amounts of the hydroxyl group-containing polymerizable unsaturated monomers used are the macromonomer (A-1), the monomer (B),
Usually, 3 to 3 based on the total amount of (C) and (D)
It is desirably in the range of 30% by weight, preferably 5 to 25% by weight.

The pigment-dispersed resin provided by the present invention has a hydrophilic part and a hydrophobic part separated from each other in terms of stability in water and pigment dispersibility. It is desirable that the hydrophilic portion effectively works to improve the stability in an aqueous pigment dispersion (pigment dispersion paste) or an aqueous paint.

The pigment-dispersed resin (I) provided by the present invention can be a block-type pigment-dispersed resin in which the structure of a hydrophilic component and a hydrophobic component is regulated, and as a monomer component of the macromonomer (A-1). , Methacrylic acid is copolymerized, the macromonomer (A-1) is a hydrophilic component,
It is preferable that the other ethylenically unsaturated monomer (D) to be copolymerized is used as the hydrophobic component.

In this case, the other ethylenically unsaturated monomer (D) copolymerized with the macromonomer (A-1) is desirably a hydrophobic monomer, for example, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate. , Isopropyl methacrylate, n
-Butyl methacrylate, isobutyl methacrylate,
_C1-24 alkyl or cyclic alkyl methacrylate monomers such as tert-butyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, lauryl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, tridecyl methacrylate; styrene, vinyl toluene And the like can be suitably used, and styrene and its derivatives, methyl methacrylate, 2-ethylhexyl methacrylate and the like are particularly preferable.

Copolymerization : macromonomer (A-1), polymerizable unsaturated monomer containing an ionic functional group (B), nonionic polymerizable unsaturated monomer having a polyoxyalkylene chain (C) and other monomers The copolymerization of the ethylenically unsaturated monomer (D) can be carried out, for example, using a macromonomer (A-1)
And solution polymerization of monomers (B), (C) and (D) in an organic solvent in the presence of a radical polymerization initiator,
Or, such as a method of emulsion polymerization in an aqueous medium,
It can be carried out by a radical polymerization method known per se.

As the radical polymerization initiator, those mentioned as the radical polymerization initiator which can be used in the production of the macromonomer (A) can be suitably used.

In the present invention, the macromonomer (A-1) and the monomer (B) constituting the pigment dispersion resin (I)
Although the mixing ratio of (C) and (D) is not particularly limited, these macromonomers (A-1) and monomers (B) and (C) are preferably used in view of the performance of the obtained resin.
Based on the total amount of the four components (D) and (D), it is desirable to be within the following range. Macromonomer (A): 5 to 70% by weight, preferably 1
0 to 60% by weight, more preferably 10 to 50% by weight, monomer (B): 0.1 to 20% by weight, preferably 0.1 to 20% by weight.
5 to 15% by weight, more preferably 0.5 to 12% by weight, monomer (C): 1 to 40% by weight, preferably 3 to 30%
% By weight, more preferably 3 to 25% by weight, monomer (D): 20 to 90% by weight, preferably 30 to 90% by weight.
80% by weight, more preferably 35-75% by weight.

The pigment-dispersed resin (I) thus obtained has a weight average molecular weight of 3,000 to 100,000.
0, preferably 3,000 to 70,000, more preferably 5,000 to 35,000, and the resin acid value is 10 to 200 mgKOH / g,
It is preferably in the range of 10 to 150 mgKOH / g, more preferably 20 to 100 mgKOH / g.

The pigment-dispersed resin (I) provided by the method of the present invention is that the macromonomer (A-1) (that is, the macromonomer (A) having a polymerizable unsaturated group introduced therein) is copolymerized. This makes it possible to increase the molecular weight of the resin, which can be particularly advantageous for stabilizing the dispersion of the pigment dispersion, and that since the monomer (B) is copolymerized, the adsorption power to the pigment surface is improved. In addition, aggregation of pigments in an aqueous dispersion or an aqueous paint can be prevented, and dispersion stability can be imparted. In addition, since the monomer (C) is copolymerized, it has surface activity and is excellent not only in stability in an aqueous dispersion but also in agglomeration of a hydrophobic portion of a pigment dispersion resin which is advantageous for wetting on a pigment surface. Without this, the hydrophobic portion can be effectively adsorbed on the pigment surface and exhibit excellent pigment dispersibility.

Pigment-dispersed resin (II) : The pigment-dispersed resin (II) according to the present invention comprises the above-mentioned macromonomer (A-1), a polymerizable unsaturated monomer (B) containing an ionic functional group,
A copolymer (K) obtained by copolymerizing a nonionic polymerizable unsaturated monomer (C) containing a polyoxyalkylene chain and another ethylenically unsaturated monomer (D) is added with an epoxy group-containing long-chain alkyl. It is obtained by reacting a compound to introduce a long-chain alkyl group.

Copolymer (K) : The copolymer (K) was prepared in the same manner as described for the production of the pigment-dispersed resin (I), using the macromonomer (A-1), the monomer (B),
It can be produced by copolymerizing (C) and (D). The obtained copolymer (K) has a weight average molecular weight of 3,000 to 100,000, preferably 30,0.
00 to 70,000, more preferably 5,000 to 3
It is in the range of 5,000, and the resin acid value is 10 to 200 m
gKOH / g, preferably 10-150 mgKOH / g
g, more preferably in the range of 20-100 mg KOH / g.

Next, the carboxyl group and epoxy group-containing long-chain alkyl compound (F) contained in the copolymer (K)
A long-chain alkyl group is introduced into the copolymer (K) by utilizing an esterification reaction with the epoxy group.

Epoxy group-containing long-chain alkyl compound
(F) : Examples of the epoxy group-containing long-chain alkyl compound (F) include compounds having one epoxy group and one or more, preferably one, long-chain alkyl group in one molecule. Here, the long-chain alkyl group may be linear or branched and has 6 to 24 carbon atoms, preferably 8 to 20 carbon atoms, and more preferably 8 to 16 carbon atoms. Is preferred.

As the epoxy group-containing long-chain alkyl compound, for example, Cardura E10 (manufactured by Resolution, registered trademark, glycidyl ester of a branched higher fatty acid having 9 to 11 carbon atoms), 2-ethylhexyl glycidyl ether, etc. Can be mentioned.

The esterification reaction between the copolymer (K) and the epoxy group-containing long-chain alkyl compound (E) can be carried out by a conventional method, for example, by using the copolymer (K) and the epoxy group-containing long-chain alkyl compound (E). Can be carried out by adding an organic solvent, if necessary, and usually reacting at a reaction temperature of about 100 ° C to 150 ° C. At that time, it is preferable to use a tertiary amine such as N, N-dimethyllaurylamine or N, N-dimethyldodecylamine as a catalyst. In this esterification reaction, the epoxy group-containing long-chain alkyl compound (F) is added to 100 parts by weight of the copolymer (K).
However, it is usually within the range of 2 to 40 parts by weight, preferably 2 to 35 parts by weight, more preferably 5 to 30 parts by weight.

The obtained pigment dispersion resin (II) has a weight average molecular weight of 3,000 to 100,000, preferably
000-70,000, more preferably 5,000-
It is preferably in the range of 35,000, and the resin acid value is 10 to 200 mgKOH / g, preferably 10 to 1 mgKOH / g.
50 mgKOH / g, more preferably 20-100 m
It is preferably in the range of gKOH / g.

The pigment dispersing resin (II) has a long-chain alkyl group capable of improving the wettability of the pigment, and is therefore particularly suitable for dispersing a pigment having a strong lipophilic property such as phthalocyanine blue. Suitable for producing pigment dispersions of high concentration.

Pigment-dispersed resin (III) : The pigment-dispersed resin (III) of the present invention comprises a polymerizable unsaturated group and a long-chain alkyl group-introduced macromonomer (A-2), and the above-mentioned ionic functional group. It comprises a copolymer obtained by copolymerizing the contained polymerizable unsaturated monomer (B), nonionic polymerizable unsaturated monomer (C) and other ethylenically unsaturated monomer (D).

The macromonomer (A-2) is obtained by esterifying the carboxyl group-containing macromonomer (A) with the epoxy group-containing polymerizable unsaturated compound (E) and the epoxy group-containing long-chain alkyl compound (F). It can be obtained by Macromonomer (A) and compound (E)
And the esterification reaction with the compound (F) can be carried out in the same manner as the esterification reaction between the macromonomer (A) and the compound (E) when producing the macromonomer (A-1). . In this case, the compound (E) and the compound (F) may be simultaneously reacted with the macromonomer (A), or may be sequentially reacted in any order.

The quantitative ratios of the epoxy group-containing long chain alkyl compound (E) and the epoxy group-containing long chain alkyl compound (F) to the macromonomer (A) in the esterification reaction are not particularly limited. From the viewpoint of the molecular weight of the copolymer to be obtained and the dispersibility of the pigment, it is generally appropriate that the amount is within the following range with respect to 100 parts by weight of the macromonomer (A). Compound (E): 0.5 to 15 parts by weight, preferably 1 to 1
0 parts by weight, particularly preferably 1 to 8 parts by weight, compound (F): 2 to 60 parts by weight, preferably 5 to 50 parts by weight, particularly preferably 5 to 40 parts by weight.

The macromonomer (A-2) obtained by introducing a polymerizable unsaturated group and a long-chain alkyl group as described above is
Based on 1 kg of the macromonomer (A-2), the amount of the polymerizable unsaturated group introduced by esterification was from 0.005 to 2.
It is suitable to have 5 mol, preferably 0.01 to 2.0 mol, particularly preferably 0.01 to 1.6 mol.

The macromonomer (A-2), a polymerizable unsaturated monomer (B) containing an ionic functional group, a nonionic polymerizable unsaturated monomer (C) and another ethylenically unsaturated monomer (D) The copolymerization reaction with the pigment dispersion resin (I) is carried out in the same manner as in the production of the pigment dispersion resin (I) except that the macromonomer (A-2) is used instead of the macromonomer (A) in the production of the pigment dispersion resin (I). Of the macromonomer (A) and the monomers (B), (C) and (D).

The thus obtained pigment-dispersed resin (II)
I) has a weight average molecular weight of 3,000 to 100,00
0, preferably 3,000 to 70,000, more preferably 5,000 to 35,000, and the resin acid value is 10 to 200 mgKOH / g,
It is preferably in the range of 10 to 150 mgKOH / g, more preferably 20 to 100 mgKOH / g.

The pigment dispersion resin (III) is a pigment dispersion resin (I
Similar to I), it has a long-chain alkyl group capable of improving the wettability of the pigment, and therefore is particularly suitable for dispersing a highly lipophilic pigment such as phthalocyanine blue, and a pigment dispersion having a high pigment concentration. Suitable for manufacturing.

Aqueous Pigment Dispersion : The above-mentioned pigment dispersion resins all have a block structure and have a small spread in a solvent. This is very advantageous in obtaining a pigment dispersion having a particularly low viscosity as compared with a linear (random) resin or a graft resin. Further, the pigment dispersion resin,
Since the polymer is a structure-regulated polymer in which a lipophilic portion and a hydrophilic portion are separated from each other, it exhibits remarkably excellent pigment dispersibility (color-forming property).

Each of these pigment-dispersed resins has a branched structure, and can effectively form a three-dimensional repulsion layer for preventing aggregation of the pigment. This is advantageous in terms of pigment dispersibility and color development.

Further, pigment dispersion resins (II) and (III)
Has a long-chain alkyl group introduced in the molecule, has improved pigment wettability, and is particularly advantageous for producing a pigment dispersion having a high pigment concentration without causing a significant increase in viscosity. . As described above, any of the pigment dispersion resins of the present invention is useful for producing a pigment dispersion.

The aqueous pigment dispersion of the present invention contains the above-mentioned pigment dispersion resin, pigment, aqueous medium, basic neutralizer, and, if necessary, pigment dispersant and other additives.

Examples of the above pigments include brilliant pigments such as aluminum powder, copper powder, nickel powder, stainless powder, chromium powder, mica-like iron oxide, mica powder coated with titanium oxide, mica powder coated with iron oxide, and brilliant graphite. ; Pink E
B, organic red pigments such as azo and quinacridone, organic blue pigments such as cyanine blue and cyanine green, organic yellow pigments such as benzimidazolone, isoindoline and quinophthalone; titanium white, titanium yellow, Examples include inorganic color pigments such as red iron oxide, carbon black, graphite, iron oxide, and various calcined pigments. The mixing ratio of the pigment is not particularly limited, but is usually 10 to 3,000 parts by weight, based on 100 parts by weight of the pigment-dispersed resin.
It is particularly preferable that the amount is in the range of 15 to 2,000 parts by weight from the viewpoints of pigment dispersibility, dispersion stability, and coloring power of the obtained pigment dispersion.

Examples of the aqueous medium include water and a water-organic solvent mixed solution obtained by dissolving an organic solvent such as a water-soluble organic solvent in water. As an organic solvent,
For example, water-soluble organic solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol, propyl propylene glycol, butyl cellosolve, propylene glycol monomethyl ether, and 3-methyl 3-methoxybutanol; poorly soluble solvents such as xylene, toluene, cyclohexanone, hexane, and pentane; Examples include insoluble organic solvents. The organic solvents can be used alone or in combination of two or more. As the organic solvent, a solvent mainly composed of a water-soluble organic solvent is preferable. The mixing ratio of water and the organic solvent is not particularly limited, but the content of the organic solvent is 5% of the mixed solution.
0 wt% or less, especially 35 wt% or less is desirable. If the ratio is out of this range, there is a possibility that a water-based paint cannot be substantially constituted. The mixing ratio of the aqueous medium is not particularly limited, but usually, based on 100 parts by weight of the pigment dispersion resin,
It is preferably from 50 to 5,000 parts by weight, particularly from 100 to 3,000 parts by weight, from the viewpoints of viscosity at the time of pigment dispersion, pigment dispersibility, dispersion stability and production efficiency.

The basic neutralizing agent functions to neutralize the carboxyl groups in the pigment-dispersed resin and to make the pigment-dispersed resin water-soluble or water-dispersible. Specific examples thereof include ammonium hydroxide. , Sodium hydroxide, inorganic bases such as potassium hydroxide, aminomethyl propanol,
Amines such as aminoethylpropanol, dimethylethanolamine, triethylamine, diethylethanolamine, dimethylaminopropanol and aminomethylpropanol can be mentioned. The compounding amount of the basic neutralizing agent is a quantitative ratio that enables water-solubilization or water-dispersion, and is a ratio where the neutralization equivalent of the carboxyl group in the pigment dispersion resin is usually 0.3 to 1.5. Is preferred.

Examples of the pigment dispersant optionally used include, for example, Disperby manufactured by BYK-Chemie.
k184, 190, and 191; and other additives include an antifoaming agent, a preservative, a rust inhibitor, and a plasticizer. In consideration of the dispersibility of the pigment and the stability of the paste, the amount of each of these components is desirably 50 parts or less based on 100 parts by weight of the pigment dispersion resin.

The above-mentioned aqueous pigment dispersion comprises a binder resin for paint, and, if necessary, an aqueous medium, fine polymer particles, a curing catalyst, a basic neutralizer, an ultraviolet absorber, an ultraviolet stabilizer,
An aqueous coating composition can be obtained by blending with a coating surface adjuster, an antioxidant, a fluidity adjuster, an additive such as a silane coupling agent, and the like, and stably dispersing the same in an aqueous medium.

The binder resin for paints includes a base resin and a curing agent which can be used for water-soluble or water-dispersible paints, such as a hydroxyl-containing acrylic resin, a hydroxyl-containing polyester resin, and an epoxy-containing copolymer resin. ,
Examples of water-based coating resins, such as carboxyl group-containing high acid value resins, amino resins, and polyisocyanate compounds which may be blocked, may be used alone or in combination of two or more. Can be used. The polyisocyanate compound which may be blocked includes both a blocked polyisocyanate compound in which isocyanato groups are blocked and a non-blocked polyisocyanate compound.

As the above-mentioned hydroxyl-containing acrylic resin, for example, a hydroxyl-containing polymerizable unsaturated monomer such as 2-hydroxyethyl (meth) acrylate and another polymerizable unsaturated monomer are copolymerized in the presence of a radical polymerization initiator. Weight average molecular weight obtained by polymerization is about 2,000 to 10
Those in the range of about 0000, especially in the range of 5,000 to 50,000 are preferred.

Examples of the hydroxyl group-containing polyester resin include polyhydric alcohols such as ethylene glycol, butylene glycol, 1,6-hexanediol, trimethylolpropane, and pentaerythritol, and adipic acid, isophthalic acid, terephthalic acid, and phthalic anhydride. Acid, hexahydrophthalic anhydride, a weight average molecular weight of about 1,000 to 100,000 obtained by a condensation reaction with a polycarboxylic acid component such as trimellitic anhydride,
Particularly, those in the range of 1,500 to 70,000 are preferable.

[0086] Examples of the amino resins used as curing agent, melamine resins are common, inter alia ether monohydric alcohol C _{1 to 4} at least a portion of the methylol groups in methylolated melamine resin and methylolated melamine resin The melamine resin is preferably a water-soluble or water-dispersible resin, but a water-insoluble resin can also be used.

Commercially available melamine resins include, for example, U-Van 20SE-60 and U-Van 225 (all of which are manufactured by Mitsui Chemicals, trade name), Super Beckamine G
Butyl etherified melamine resins such as 840 and G821 (all of which are manufactured by Dainippon Ink and Chemicals, Inc.); Sumimar M-100, M-40S, and M-55
(These are all manufactured by Sumitomo Chemical Co., Ltd., trade name), Cymel 3
03, 325, 327, 350, and 370 (all, manufactured by Mitsui Cytec Co., Ltd., trade name), Nikarac MS17, MS15 (all, manufactured by Sanwa Chemical Co., trade name), Regin 741 ( Methyl etherified melamine resin such as Monsanto (trade name); Cymel 2
35, 202, 238, 254, 272, 1
A mixed etherified melamine resin of methylation and isobutylation such as 130 (all of which are manufactured by Mitsui Cytec Co., Ltd., trade name) and Sumamil M66B (trade name of Sumitomo Chemical Co., Ltd.); Melamine resin mixed with methylation and n-butylation such as Nicarac MS95 (trade name, manufactured by Sanwa Chemical Co., Ltd.).

The polyisocyanate compound which may be used as a curing agent and which may be blocked may be either a polyisocyanate compound having a free isocyanate group or a polyisocyanate compound having an isocyanate group blocked.

Examples of the polyisocyanate compound having a free isocyanate group include aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; cycloaliphatic diisocyanates such as hydrogenated xylylene diisocyanate and isophorone diisocyanate; tolylene diisocyanate Aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate; triphenylmethane-4,4 ', 4 "-triisocyanate,
It has three or more isocyanate groups such as 5-triisocyanatobenzene, 2,4,6-triisocyanatotoluene and 4,4'-dimethyldiphenylmethane-2,2 ', 5,5'-tetraisocyanate Organic polyisocyanate itself such as a polyisocyanate compound, or an adduct of each of these organic polyisocyanates with a polyhydric alcohol, a low molecular weight polyester resin or water, or a cyclized polymer of each of the above organic polyisocyanates, May be an isocyanate / biuret compound.

Commercially available polyisocyanate compounds having a free isocyanate group include, for example, Vernock D-750, -800, DN-950, and DN-950.
-970, DN-15-455 (all, manufactured by Dainippon Ink & Chemicals, Inc.), Desmodur L, N, HL, N3390 (all, manufactured by Sumitomo Bayer Urethane Co., trade name), Takenate D-102, -20
2, -110, -123N (all, manufactured by Takeda Pharmaceutical Company, trade name), Coronate EH, L, H
L. and 203 (all, manufactured by Nippon Polyurethane Industry Co., Ltd., trade name), Duranate 24A-90CX (trade name, manufactured by Asahi Kasei Kogyo Co., Ltd.) and the like.

As the isocyanate group-blocked polyisocyanate compound, the isocyanate group of the above-mentioned polyisocyanate compound having a free isocyanate group can be converted to a known blocking agent such as oxime, phenol, alcohol, lactam, malonic ester or mercaptan. Blocked by. Examples of these typical commercial products include Vernock D-550
(Manufactured by Dainippon Ink and Chemicals, Inc., trade name), Takenate B
-815-N (trade name, manufactured by Takeda Pharmaceutical Co., Ltd.), Aditol VXL-80 (trade name, manufactured by Hoechst AG, Germany), Coronate 2507 (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.), Desmodur N3500 (Sumitomo Bayer Urethane Co., trade name).

As the aqueous solvent used as required, the same solvents as those which can be used as an aqueous medium optionally used in producing the pigment dispersion can be used.

The polymer fine particles are polymers which are not dissolved in the coating composition of the present invention and are dispersed as fine particles. Usually, those having an average particle diameter in the range of 0.01 to 1 μm are preferable. The polymer particles may or may not be cross-linked inside the particles, but preferably are internally cross-linked. As the polymer fine particles, those known per se as a fluidity modifier for paints in the field of paints can be used.

When the curing agent is a polyisocyanate compound which may be blocked, an organic metal catalyst such as dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate; triethylamine, diethanolamine, etc. When the curing agent is an amino resin such as a melamine resin, a sulfonic acid compound such as paratoluenesulfonic acid, dodecylbenzenesulfonic acid, dinonylnaphthalenesulfonic acid, or the like can be used. Amine-neutralized sulfonic acid compounds can be suitably used.

Examples of the ultraviolet absorber include benzophenone-based, benzotriazole-based, cyanoacrylate-based, salicylate-based, and oxalic anilide-based compounds. Examples of the ultraviolet stabilizer include a hindered amine compound.

The aqueous coating composition of the present invention can be used as a coloring coating composition (including a metallic coating and an interference color coating) containing various pigments such as a coloring pigment, a metallic pigment and an interference color pigment. Among them, it can be suitably used as a top coat for automobile coating (colored base coat).

The coating composition of the present invention can be applied to various objects to be coated by a conventional method.
By baking at a temperature of about 10 to 60 minutes, a cured coating film can be formed. In the case of baking for a short time, for example, the maximum material reaching temperature is about 180 ° C. to 250 ° C.
A cured coating film can also be formed by baking for about 20 to 60 seconds under the following conditions.

The object to be coated with the coating composition of the present invention is
There is no particular limitation, for example, metal substrates such as steel plate, aluminum, and tin; other substrates such as mortar, cement, plastics, and glass; and surface treatment and / or coating film formation on these substrates. Among them, a metal substrate, in particular, a substrate based on a steel plate, and a substrate based on plastics can be suitably used.

Examples of the steel sheet include cold-rolled steel sheet, hot-dip galvanized steel sheet, electro-galvanized steel sheet, aluminum-plated steel sheet, stainless steel sheet, copper-plated steel sheet, tin-plated steel sheet, lead-tin alloy-plated steel sheet (turn sheet); Zinc alloy-plated steel sheets such as zinc, aluminum-zinc, nickel-zinc and the like can be mentioned. Examples of the steel sheet subjected to the surface treatment include a steel sheet obtained by subjecting the above steel sheet to a chemical conversion treatment such as a phosphate treatment or a chromate treatment.

[0100] Examples of the object to be coated with the coating film include:
Examples thereof include those in which a substrate is subjected to a surface treatment as necessary and a primer coating film is formed thereon, and those in which an intermediate coating film is formed on the primer coating film.

When the coating composition of the present invention is used as a top coating for automotive coating, a typical example of the object to be coated is to apply a primer to a chemical conversion-treated steel sheet by electrodeposition and, if necessary, apply an intermediate coating. Painted materials, various plastic base materials (subjected to surface treatment, primer coating, intermediate coating, etc. as necessary), and composite members in which these materials are combined are exemplified.

The above-mentioned electrodeposition paint may be any of an anionic type and a cationic type, but a cationic type having good anticorrosive property is desirable. Known cationic electrodeposition paints can be used. For example, those containing a base resin having a hydroxyl group and a cationic group as a resin component and a curing agent such as a blocked polyisocyanate compound can be suitably used. it can.

The aqueous coating composition of the present invention comprises a composition for forming a colored coating film for one coat and one bake on a substrate, and two coats and one bake (2C1B) on a substrate and two coats and two bake (2C2B) 3 coats 1 bake (3C1B), 3 coats 2 bake (3C2B) or 3 coats 3 bake (3C3
B) It can be suitably used as a top-coating colored base coating composition in a method or the like.

When the coating composition of the present invention is used as a top coating color coating for automobiles, for example, an uncured or cured intermediate coating applied on a primer coating film such as an electrodeposition coating film or on a primer coating film On the coating film, for example, by applying a method such as electrostatic atomization coating (bell type), air spray coating or the like, the dried film thickness is usually applied to about 10 to 60 μm, and left at room temperature for several minutes, After forcibly drying for several minutes in the range of about 50 to 80 ° C., apply a clear top coating,
By baking at a temperature of about 20 to 180 [deg.] C. for about 10 to 60 minutes, a top-coating colored coating film can be formed. Further, on the uncured or cured topcoat colored coating film coated as described above, a topcoat clear paint is applied by means such as electrostatic atomization coating (bell type or the like), air spray coating, or the like.
An overcoated multilayer coating film can also be formed by coating and curing so that the dry film thickness is usually about 20 to 100 μm.

Examples of the top clear coating composition to be applied on the top coating film include acrylic resins, vinyl resins, polyester resins, and alkyds having a crosslinkable functional group (for example, a hydroxyl group, an epoxy group, a carboxyl group, an alkoxysilane group, etc.). Resin, at least one base resin such as a urethane resin, and an alkyl etherified melamine resin, a urea resin, a guanamine resin, a polyisocyanate compound which may be blocked, an epoxy resin, and a carboxyl resin for crosslinking and curing the base resin. A clear top coating comprising at least one crosslinking agent such as a group-containing compound is preferred, and the mixing ratio of the base resin and the crosslinking agent is usually 50 to 90% by weight based on the sum of the two. %,
It is desirable that the cross-linking agent component be 10 to 50% by weight.

The form of the clear top coating composition is not particularly limited, and may be an organic solvent type, a non-aqueous dispersion type,
Aqueous solution type, aqueous dispersion (slurry) type, high solid type,
Any form such as a powder type can be used.

[0107]

EXAMPLES Hereinafter, the present invention will be further clarified with reference to Production Examples, Examples, and Comparative Examples. Unless otherwise specified, “parts” and “%” are “parts by weight” and “% by weight”, respectively.
Means

Production of Macromonomer Production Example 1 Methoxypropanol 10 was placed in a conventional acrylic resin reaction tank equipped with a stirrer, thermometer, nitrogen inlet tube and reflux condenser tube.
Five parts were charged, and the mixture was heated and stirred and maintained at 105 ° C. while performing nitrogen replacement in the reaction vessel. 70 parts of methyl methacrylate, 30 parts of methacrylic acid, 1 part of azobisisobutyronitrile, 5 parts of methoxypropanol, and bis (borondifluorodimethylglyoxymate) CO
(II) A mixture consisting of 0.03 parts was added dropwise over 3 hours. After completion of the dropwise addition, the mixture was aged at 105 ° C. for 30 minutes, and then an additional catalyst mixture comprising 10 parts of methoxypropanol and 0.5 part of azobisisobutyronitrile was added dropwise over 1 hour, and then added at 105 ° C. for 1 hour. After aging, the mixture was cooled to obtain a macromonomer (C-1) solution having a solid content of 45%. The resulting macromonomer (C-1) has a resin acid value of about 195.
The weight average molecular weight was about 1,800 in mgKOH / g.

Production Examples 2 and 3 The same procedures as in Production Example 1 were carried out except that the composition shown in Table 1 was used, to obtain macromonomer solutions (C-2) and (C-3). Was. Table 1 shows the solid content, resin acid value, and weight average molecular weight of each of the obtained macromonomer solutions.
It was shown to.

[0110]

[Table 1]

Production Example 4 of Polymerizable Unsaturated Group-Introduced Macromonomer Production Example 4 The macromonomer (Production Example 1) obtained in Production Example 1 was placed in a usual acrylic resin reaction tank equipped with a stirrer, a thermometer, an air introduction tube, and a reflux condenser. C-1) 222.2 parts of the solution and 6.8 parts of methoxypropanol were charged, and the mixture was heated and stirred at 120 ° C. while air was introduced into the reaction vessel to replace the air. In this, 4-t-butyl pyrocatechol 0.05
, 0.1 part of N, N-dimethylaminoethanol and 5.4 parts of glycidyl methacrylate, reacted at 120 ° C. for 2 hours, and introduced a macromonomer (D- 1) A solution was obtained. The obtained macromonomer (D-1) has a resin acid value of about 175 mgK.
At OH / g, the weight average molecular weight was about 1,900.

Production Examples 5 to 7 The same procedure as in Production Example 4 was carried out except that the composition shown in Table 2 below was used, and each macromonomer having a polymerizable unsaturated group introduced by an esterification reaction was prepared. solution
[(D-2), (D-3) and (D-4)] were obtained. The solid content, resin acid value, and weight average molecular weight of each of the obtained macromonomer solutions are shown in Table 2 below.

[0113]

[Table 2]

Production Example 1 of Pigment-Dispersed Resin In an ordinary acrylic resin reaction tank equipped with a stirrer, a thermometer and a reflux condenser, 32 parts of ethylene glycol monobutyl ether, the macromonomer obtained in Production Example 4 (D- 1)
55.6 parts (25 parts by solid content) of the solution were charged, and the mixture was heated and stirred and maintained at 110 ° C. In this, 20 parts of styrene,
28 parts of methyl methacrylate, 15 parts of n-butyl methacrylate, 5 parts of 2-hydroxyethyl methacrylate,
2 parts of dimethylaminoethyl methacrylate, NF bioisomer PEM6E (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name, polyethylene glycol monomethacrylate, molecular weight about 35)
0) A mixture of 5 parts, 1 part of azobisisobutyronitrile and 5 parts of isobutyl alcohol was added dropwise over 3 hours. After completion of the dropwise addition, the mixture was aged at 110 ° C. for 30 minutes, and then an additional catalyst mixed solution comprising 15 parts of ethylene glycol monobutyl ether and 0.5 part of azobisisobutyronitrile was added dropwise over 1 hour. Then, the mixture was aged at 110 ° C. for 1 hour, and then cooled to obtain a pigment-dispersed resin (A-
1) A solution was obtained. The obtained pigment dispersion resin (A-1)
The resin acid value was about 43 mgKOH / g, and the weight average molecular weight was about 13,500.

Examples 2 to 9 and Comparative Examples 1 to 4 The procedure of Example 1 was repeated, except that the composition was as shown in Table 3 below. -2) to (A-9) and pigment dispersion resin solutions (AC-1) to (AC-4) for comparison were obtained. The solid content of these pigment dispersion resin solutions, and the resin acid value and weight average molecular weight of the pigment dispersion resin are shown in Table 2 below.

(Note) in Table 2 below has the following meanings, respectively. (* 1) NF Bisomer S10W: trade name, 50% water-diluted product of methoxypolyethylene glycol monomethacrylate, molecular weight about 1080, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. (* 2) NF Bisomer S20W: trade name, 50% water-diluted product of methoxypolyethylene glycol monomethacrylate, molecular weight of about 2080, manufactured by Daiichi Kogyo Seiyaku Co., Ltd. (* 3) Kajura E10: trade name, manufactured by Resolution, registered trademark, glycidyl ester of a branched higher fatty acid having 9 to 11 carbon atoms.

[0117]

[Table 3]

[0118]

[Table 4]

Preparation of Aqueous Pigment Dispersions Examples 10 to 25 and Comparative Examples 5 to 14 Each of the pigment dispersion resin solutions obtained in Examples 1 to 9 and Comparative Examples 1 to 4, the pigment and the neutralized amine (N, N -Dimethylaminoethanol) and deionized water, placed in a 225 cc wide-mouth glass bottle with the composition shown in Table 4 below, and added with glass beads having a diameter of about 1.3 mmφ as a dispersion media, sealed, and placed on a paint shaker. And dispersed for 4 hours in each of the aqueous pigment dispersions (B-1) to (B-15), and (BC-
1) to (BC-10) were obtained.

(Note) in Table 4 has the following meanings. (Note 1) RT355D: Organic red pigment manufactured by Ciba Specialty Chemicals Inc., trade name is “cinquasi
a) Magenta RT355D ". (Note 2) G314: Organic blue pigment manufactured by Sanyo Dyeing Co., Ltd., trade name is “Cyanine Blue G314”. (Note 3) MT500HD: manufactured by Teica Co., Ltd., trade name,
Inorganic white pigment. (Note 4) Raven5000UIII: trade name, carbon black pigment, manufactured by Columbia Carbon Co., Ltd.

Examples 10 to 25 and Comparative Examples 5 to 14
Each of the aqueous pigment dispersions obtained in the above was subjected to a performance test based on the following test method. The test results are shown in Table 4 below.

Test Method Coating Appearance: Each pigment-dispersed paste was 100 × 200 mm
Was applied with a bar coater to a dry film thickness of 15 μm and baked at 140 ° C. for 15 minutes. The degree of turbidity of the coating film formed on the film was visually evaluated according to the following criteria. ：: uniform and no turbidity Δ: slight turbidity observed X: considerable turbidity observed

Gloss: The pigment dispersion was applied on a PET film with a doctor blade (4 mil, 100 μm), and the gloss of the dried coating film was measured according to JIS K5400 7.6 (19).
90), the 60 ° specular reflectance of each coating film was measured.

Light transmittance: The pigment dispersion was applied on a PET film with a doctor blade (4 mil, 100 μm).
The light transmittance (%) of the dried coating film was measured using a turbidimeter (COH-3).
00) and the transparency was evaluated by the following formula. Light transmittance (%) = 100 × [1− (scattered light intensity / irradiation light intensity)] Viscoelastic properties: Viscosity [viscosity [Pascal · sec (Pa)・ Se
c)] and the yield value (dyn / cm ² ) were measured.

[0125]

[Table 5]

[0126]

[Table 6]

[0127]

[Table 7]

Synthesis Example 1 Ethylene glycol monobutyl ether 40 was added to an acrylic resin reaction tank equipped with a stirrer, thermometer, reflux condenser and the like.
And 30 parts of isobutyl alcohol, and heat and stir until the temperature reaches 100 ° C.
It was dropped over time.

Styrene 10 parts Methyl methacrylate 38 parts n-butyl acrylate 25 parts 2-hydroxyethyl methacrylate 20 parts Acrylic acid 7 parts 2,2'-azobisisobutyronitrile 1 part Isobutyl alcohol 5 parts After dropping, , After holding at 100 ° C. for another 30 minutes,
An additional catalyst solution, which was a mixture of 0.5 part of 2'-azobisisobutyronitrile and 10 parts of ethylene glycol monobutyl ether, was added dropwise over 1 hour. 100 ° C
After stirring for 1 hour, the mixture was cooled, 15 parts of isobutyl alcohol was added, and when the temperature reached 75 ° C., 4 parts of N, N-dimethylaminoethanol was added. A solution (AP-1) was obtained.

Synthesis Example 2 An acrylic polymer having a solid content of 50% was prepared in the same manner as in Synthesis Example 1 except that the composition of the mixture of monomers and the like to be dropped was changed as shown in Table 4 below. Solution (AP-2) was synthesized. Table 5 below shows the characteristic values of the acrylic polymers obtained in Synthesis Examples 1 and 2.

Synthesis Example 3 317.8 parts of isophthalic acid, 196.5 parts of hexahydrophthalic acid, and 372 parts of adipic acid were placed in a reaction vessel equipped with a stirrer, thermometer, rectification tower, nitrogen inlet tube, reflux condenser and the like. .6
Part, 268 parts of neopentyl glycol, 217.8 parts of 1,6-hexanediol, trimethylolpropane 26
After 3.5 parts were charged and heated and stirred to reach 160 ° C, the temperature was raised to 235 ° C over 3 hours. After aging for 1.5 hours after the temperature was raised, the rectification column was switched to a reflux condenser, and 100 parts of toluene was introduced to carry out a reaction under reflux. 2 as it is
After performing the reaction at 35 ° C. for 6 hours, toluene was removed under reduced pressure, and the mixture was cooled to 170 ° C. and trimellitic anhydride 122.
5 parts were added. After aging at 170 ° C. for 30 minutes, 322 parts of ethylene glycol monobutyl ether was added, and then cooled to 80 ° C. Thereafter, 4 parts of dimethylethanolamine was added, and the mixture was kept at 80 ° C. for 30 minutes. Then cool to 50 ° C and deionized water 2600
Part, and stirred for 30 minutes to obtain a solid content of 35%.
A polyester resin (PP-1) was obtained.

Synthesis Example 4 The same procedure as in Synthesis Example 3 was carried out except that the composition was changed as shown in Table 5 below, and the solid content concentration was changed to 35.
% Of a polyester resin (PP-2). Table 6 below shows resin special values of the polyester resins obtained in Synthesis Examples 3 and 4.

[0133]

[Table 8]

[0134]

[Table 9]

Synthesis Example 5 Synthesis of Acrylic Emulsion 400 parts of deionized water and Newcol 562SF were placed in an acrylic resin reaction tank equipped with a stirrer, thermometer, reflux condenser and the like.
2.4 parts (trade name, manufactured by Nippon Emulsifier Co., Ltd., surfactant) were added, and the mixture was heated and stirred to reach 82 ° C., and then a pre-emulsion preparation mixture was charged. The mixture for preparing a pre-emulsion was composed of 6 parts of styrene and n-butyl acrylate.
5 parts, allyl methacrylate 0.5 parts, Newcol 5
0.175 part of 62SF and 7.5 parts of deionized water are mixed, and about 1000 rpm by a disper. For 10 minutes. Twenty minutes after charging the pre-emulsion preparation mixture, 15 parts of deionized water and 0.54 part of potassium persulfate were added. After 10 minutes, while maintaining the temperature at 82 ° C., 114 parts of styrene and 16 parts of n-butyl acrylate
1.5 parts, allyl methacrylate 9.5 parts, Newcol 562SF 3.325 parts and deionized water 142.5
Parts and mixed with a disper at about 1000 rpm. At 10
Stir for 15 minutes and add 15 parts of deionized water and 0.5 parts of potassium persulfate.
The first monomer mixture to which 4 parts were added was added dropwise over 3 hours. After completion of the dropwise addition, the mixture was kept at 82 ° C. for 30 minutes, and then 50 parts of styrene, 23 parts of n-butyl acrylate, 10 parts of 2-hydroxyethyl acrylate, and 5 parts of methacrylic acid
Parts, 1.6 parts of Newcol 562SF and 6 parts of deionized water
0 parts are mixed and about 1000 rpm with a disper. At 1
Stir for 0 minutes and add 15 parts of deionized water and 0.1 ml of potassium persulfate.
A second monomer mixture to which 54 parts were added was added dropwise over 1.5 hours. After completion of the dropwise addition, the mixture was kept at 82 ° C for 30 minutes, cooled, and when the temperature reached 75 ° C, a mixture of 7 parts of N, N-dimethylaminoethanol and 280 parts of deionized water was added dropwise over 15 minutes. After that, the mixture was kept at 75 ° C. for 15 minutes, and then cooled to synthesize an acrylic emulsion having a solid content of 30%.

Production of Colored Coating Composition Example 26 The pigment-dispersed paste (B-1) obtained in Example 10 was used as a starting material.
2 parts (solids content 20 parts, of which 10 parts pigment, 1 dispersion resin
0 parts), the acrylic polymer solution obtained in Synthesis Example 1 (AP-
1) 40 parts (20 parts in solid content), 57.1 parts (2 in solid content) of the polyester polymer (PP-1) obtained in Synthesis Example 3
0 parts), 50 parts of Cymel 325 (trade name, methyl etherified melamine resin solution having a solid content of about 80%, manufactured by Mitsui Cytec Co., Ltd.) (40 parts by solid content), and the acrylic emulsion 33 obtained in Synthesis Example 5 0.3 parts (10
Parts), and then “Primal ASE-60” (trade name, manufactured by Nippon Acrylic Chemicals, Inc., thickener) was diluted with water to a solid content of 28%, and the 28% primer ASE was diluted. Was added, and 1.2 parts of dimethylethanolamine, 230 parts of deionized water, and 30 parts of 2-ethylhexyl alcohol were further added, and the viscosity was 500 mPa · s.
A colored coating composition having a pH of about 8.5 (based on a B-type viscometer at 60 rpm) was obtained.

Examples 27 to 34 and Comparative Examples 15 to 18 Colored coating compositions were obtained in the same manner as in Example 26 except that the composition was changed as shown in Table 7 below.

Using the colored coating compositions obtained in Examples 26 to 34 and Comparative Examples 15 to 18, each test coated plate was prepared according to the following method for preparing a test coated plate.

Method of preparing test coated plate Electrodeposited an epoxy resin-based cationic electrodeposition paint on a 0.8 mm thick cold-rolled dull steel plate that had been subjected to zinc phosphate chemical conversion treatment so that the dry film thickness was about 20 μm. On the baked electrodeposition coating film, an automotive polyester resin-based intermediate coating material was applied and baked so as to have a dry film thickness of about 20 μm. This coated plate is water-dried with # 400 sandpaper, drained and dried,
Degreasing with petroleum benzine. Then, on the degreased plate, each of the above colored coating compositions whose viscosity was adjusted to 500 mPa · s (B-type viscometer 60 rpm) was dried at a booth humidity of 70% using a minibell rotating electrostatic coating machine. About 15μm thick
After setting at room temperature for about 5 minutes, the mixture was baked in an electric hot air dryer at 80 ° C. for 10 minutes to volatilize most of the volatile components. Thereafter, the temperature of the coating film was returned to room temperature, and an acrylic resin clear paint for automobiles, Magicalon TC71 (manufactured by Kansai Paint Co., Ltd.) was applied so as to have a dry film thickness of 40 μm.
Each test coating was prepared by baking at 40 ° C. for 30 minutes.

Various tests were performed on these test coated plates based on the following test methods. The test results are shown in Table 7 below.
Shown in

Test Method Appearance of Coating Film: The finished appearance of the coating film was comprehensively investigated from the sense of luster and the feeling of holding, and evaluated according to the following criteria. ：: good, △: bad, ×: extremely poor.

Gloss: JIS K5400 7.6 (19
90), the 60 ° specular reflectance of each coating film was measured.

Sharpness: Measured with a sharpness gloss meter PGD-IV, manufactured by Japan Color Research Laboratory. The higher the value, the better the sharpness.

Adhesion: JIS K-5400 8.5.
2 (1990) According to the crosscut-tape method, 11 parallel vertical and horizontal straight lines are drawn at 1 mm intervals on the surface of the coating film of the test plate so as to reach the substrate with a cutter knife, and the distance is 1 mm. 100 × 1 mm squares were created. A cellophane adhesive tape was adhered to the surface, and the degree of peeling of the squares when the tape was abruptly peeled was observed and evaluated according to the following criteria. ：: 90 or more squares of the coating film remained, Δ: the coating film was peeled, and the number of remaining squares was 50 or more and 90
Less than, ×: The coating film peeled off, and the number of remaining squares was less than 50.

Acid resistance: 0.5 cc of artificial rain having the following composition was dropped on the coating film of the test plate, heated for 30 minutes on a hot plate heated to 80 ° C., washed with water, and the coated surface was visually observed. The following criteria were used for evaluation. ：: No change was observed on the painted surface, Δ: Whitening and swelling were not observed on the painted surface, but a step was observed at the boundary, ×: Whitening or swelling was observed on the painted surface, 1 mg / g NaNO ₃ aqueous solution 1
9.6 g, 1 mg / g KNO ₃ aqueous solution 5.2 g, 1 m
3.7 g of 1 g / g CaCl ₂ .2H ₂ O aqueous solution, 1 mg
/ G MgSO ₄ .7H ₂ O aqueous solution 8.2 g, 1 mg / g
g of (NH ₄ ) ₂ SO ₄ aqueous solution 73.3 g, 0.1N H ₂ SO ₄ aqueous solution 30.0 g, 0.1 N HNO ₃ aqueous solution 20.0 g, 0.05 N HCl aqueous solution 10.0 g and 1 mg / g of NaF aqueous solution (4.7 g), H ₂ S
The pH was adjusted to 1.0 with O ₄ .

Solvent resistance: In a room at 20 ° C., about 1 kg was applied to the painted surface with gauze impregnated with methyl ethyl ketone.
/ Cm ² was reciprocated 50 times over a length of about 5 cm under a load of / cm ² , and the state of the coated surface was visually evaluated according to the following criteria. ：: no change is observed on the coated surface, Δ: scratch is recognized on the coated surface, ×: whitening or swelling of the coated film is recognized.

Impact resistance: JIS K-5400
According to 3.2 (1990) Dupont impact resistance test,
The test was performed with the coated surface of the test plate facing upward with a falling weight of 500 g and a tip diameter of the hammer of about 12.7 mm, and the maximum falling weight height that would not damage the coating film was indicated. The maximum value is 50 cm.

[0148]

[Table 10]

[0149]

[Table 11]

[0150]

By using the pigment dispersing resin according to the present invention, it is possible to obtain an aqueous pigment dispersion having excellent wettability and dispersion stability even at a high pigment concentration, having a low viscosity and excellent color development. . Also, by using this aqueous pigment dispersion, the color development of the pigment, the finished appearance of the coating film,
In addition, it is possible to obtain a coating composition which is excellent in coating film performance such as weather resistance and physical properties, has good pigment dispersion stability, and can have a high pigment concentration.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J027 AA01 BA08 BA13 CB08 4J037 AA04 AA05 AA17 CB01 CB12 CB28 CC16 CC23 CC29 DD04 DD23 FF02 FF09 FF17 FF18 4J038 CC061 CG031 CG141 CH171 CH201 CR061 GA06 MA08 GA13 NA01 NA05 NA11 NA26 PB07 4J100 AB02P AJ02P AL02P AL02S AL08P AL08Q AL08R AL09P AL10Q AM21Q BA03P BA04R BA08P BA08R BA31P BA31Q BA32Q BA56Q BC53P CA03 FA04 HA11 HC39 HC88 JA15

Claims (12)

[Claims] At least one selected from methacrylic acid, methacrylic acid ester and styrene in the presence of a metal complex or an addition-cleavable chain transfer agent which is a catalytic chain transfer agent and, if necessary, a radical polymerization initiator. Resin acid value obtained by copolymerizing a kind of copolymerizable monomer with 50 to 450 mg
KOH / g carboxyl group-containing macromonomer (A)
At least one selected from a polymerizable unsaturated group-containing macromonomer (A-1) obtained by subjecting an epoxy group-containing polymerizable unsaturated compound (E) to an esterification reaction, an amino group, a quaternary ammonium base and a sulfonic acid group Monomer comprising one type of ionic functional group-containing polymerizable unsaturated monomer (B), non-ionic polymerizable unsaturated monomer having a polyoxyalkylene chain (C), and other ethylenically unsaturated monomer (D) The weight average molecular weight obtained by copolymerizing the mixture in the presence of a radical polymerization initiator is 3,000 to 100,000, and the resin acid value is 1
Pigment dispersion resin in the range of 0 to 200 mgKOH / g. 2. The pigment-dispersed resin according to claim 1, wherein the metal complex used for producing the macromonomer (A) is a cobalt complex. 3. The pigment-dispersed resin according to claim 1, wherein the addition-cleavable chain transfer agent used for producing the macromonomer (A) is 2,4-diphenyl-4-methylpentene. 4. The mixing ratio of methacrylic acid, which constitutes the macromonomer (A), and at least one copolymerizable monomer selected from methacrylic acid esters and styrene, is based on the sum of the two. The pigment-dispersed resin according to any one of claims 1 to 3, wherein 8 to 60% by weight and the copolymerizable monomer are in a range of 40 to 92% by weight. 5. The polymerizable unsaturated group-containing macromonomer (A)
-1), the amount of the polymerizable unsaturated group introduced by the esterification is changed so that the polymerizable unsaturated group-containing macromonomer (A
The pigment-dispersed resin according to any one of claims 1 to 4, wherein the content is in the range of 0.005 to 2.5 mol / kg based on -1). 6. The other ethylenically unsaturated monomer (D) contains a hydroxyl group-containing polymerizable unsaturated monomer, and the amount of the hydroxyl group-containing polymerizable unsaturated monomer is the same as that of the macromonomer (A-1) and the monomer (B). The pigment-dispersed resin according to any one of claims 1 to 5, wherein the content is in the range of 3 to 30% by weight based on the total of (C) and (D). 7. The other ethylenically unsaturated monomer (D) contains a carboxyl group-containing polymerizable unsaturated monomer, and the amount of the carboxyl group-containing polymerizable unsaturated monomer is the same as that of the macromonomer (A-1). (B),
The pigment-dispersed resin according to any one of claims 1 to 6, wherein the content is in the range of 0.1 to 20% by weight based on the sum of (C) and (D). 8. The composition of the monomer mixture to be copolymerized is based on the total of the macromonomer (A-1) and the monomers (B), (C) and (D), and the polymerizable unsaturated group-introduced macromonomer ( A-1) 5 to 70
% By weight, polymerizable unsaturated monomer containing an ionic functional group (B)
0.1 to 20% by weight, Nonionic polymerizable unsaturated monomer (C) 1 to 40% by weight
And other ethylenically unsaturated monomers (D) 20 to 9
The pigment-dispersed resin according to any one of claims 1 to 7, wherein the amount is 0% by weight. 9. A polymer containing at least one ionic functional group selected from the group consisting of the polymerizable unsaturated group-containing macromonomer (A-1) according to claim 1, an amino group, a quaternary ammonium base and a sulfonic acid group. A monomer mixture comprising an unsaturated unsaturated monomer (B), a nonionic polymerizable unsaturated monomer having a polyoxyalkylene chain (C) and another ethylenically unsaturated monomer (D) is copolymerized in the presence of a radical polymerization initiator. The copolymer (K) obtained by polymerization is reacted with an epoxy group-containing long-chain alkyl compound (F) to introduce a long-chain alkyl group, so that the weight-average molecular weight obtained is 3,000 to 100,000. And a pigment-dispersed resin having a resin acid value in the range of 10 to 200 mgKOH / g. 10. A long-chain alkyl group obtained by reacting a carboxyl group-containing macromonomer (A) with an epoxy group-containing polymerizable unsaturated compound (E) and an epoxy group-containing long chain alkyl compound (F), and a polymerizable compound. A macromonomer containing an unsaturated group (A-2), a polymerizable unsaturated monomer containing at least one ionic functional group selected from an amino group, a quaternary ammonium base and a sulfonic acid group (B); a polyoxyalkylene chain Having a weight average molecular weight of 3, obtained by copolymerizing a monomer mixture comprising a nonionic polymerizable unsaturated monomer (C) having the formula (I) and another ethylenically unsaturated monomer (D) in the presence of a radical polymerization initiator. 000-100,000 and resin acid value is 1
Pigment dispersion resin in the range of 0 to 200 mgKOH / g. 11. An aqueous pigment dispersion containing the pigment dispersion resin according to any one of claims 1 to 10, a pigment, an aqueous medium, a basic neutralizing agent, and if necessary, a dispersing aid. 12. An aqueous coating composition containing the aqueous pigment dispersion according to claim 11.