KR20010058968A - Acrylic resin composition - Google Patents

Abstract

PURPOSE: An acrylic resin composition for dispersing pigment is provided to enhance the dispersing ability of carbon black and storage capacity of paint by comprising desired long-chained monomer compounds having specific chemical structures. CONSTITUTION: The acrylic resin composition comprises 3-10 wt.% of long-chain amine modified hydroxyl monomer defined by formula 1 (wherein R1 is hydrogen or methyl group, R2 is alkyl group having C2-C4 and n is integer of 2-4); 10-30 wt.% of epsilon-caprolactone modified long-chained primary hydroxyl monomer defined by formula 2 (wherein R1 and n are same as in formula 1); 15-30 wt.% of short-chain hydroxyl monomer; 1-5 wt.% of short-chain amine monomer; and 25-71 wt.% of universal acrylic monomer. The acrylic resin has a molecular weight of 3,000-20,000, 50-150mgKOH/g of hydroxyl values, 5-30mgKOH/g of amine values and a glass transition temperature of -40 to 10 deg.C.

Description

Acrylic resin composition for pigment dispersion

The present invention relates to an acrylic resin composition for pigment dispersion, and more particularly, a long chain amine-modified hydroxyl monomer represented by the following formula (1), an ε-caprolactone modified long-chain primary hydroxyl monomer represented by the following formula (2), Acrylic resin for dispersing pigments, which is composed of short-chain hydroxyl monomers, short-chain amine monomers and general-purpose acrylic monomers, which can improve pigment dispersibility of automotive top coats, in particular, carbon black, and improve paint storage. It relates to a composition.

Formula 1

Wherein R ₁ is a hydrogen atom or a methyl group, R ₂ is an alkyl group having 2 to 4 carbon atoms, and n is an integer of 2 to 4;

Formula 2

Wherein R ₁ and n are as described above.

Generally, phenylenediamine, metal oleate, and metal octoate are used as the pigment dispersant used to further improve pigment dispersion.

In the conventional high solid automotive top coat, melamine and acrylic resin were mixed to disperse the pigment. In addition, rheology control agents such as cellulose acetate butyrate, microgel, NAD, etc. were used to prevent the orientation and sagging of the pigment to complement the appearance of the paint. At this time, the acrylic resin used has insufficient pigment dispersibility, causing flocculation during paint production, paint thickening during heat storage, and generation of crystal, and poor compatibility with rheology modifier. This hindered the appearance of paints such as sunyoung and clarity. In order to improve this, development of resin which is excellent in compatibility and excellent in pigment dispersibility is urgently required.

An object of the present invention is to mix the compounds represented by the formula (1) and (2) in order to improve the disadvantages of the conventional acrylic resin as described above and to include a short chain hydroxyl monomer, a short chain amine monomer, a general acrylic monomer and the like It is possible to improve the crosslinking reaction rate, pigment dispersibility and paint storage property by controlling the skeleton and molecular weight of the resin, and to provide an acrylic resin composition for dispersing pigment, which is excellent in compatibility and suitable for automobile coating.

Acrylic resin composition for pigment dispersion of the present invention for achieving the above object is 3 to 10% by weight of a long chain amine-modified hydroxyl monomer represented by the following formula (1), ε-caprolactone modified long chain 1 represented by the following formula (2) It is characterized by containing 10-30 weight% of primary hydroxyl monomers, 15-30 weight% of short chain hydroxyl monomers, 1-5 weight% of short chain amine monomers, and 25-71 weight% of general purpose acrylic monomers.

Formula 1

Wherein R ₁ is a hydrogen atom or a methyl group, R ₂ is an alkyl group having 2 to 4 carbon atoms, and n is an integer of 2 to 4;

Formula 2

Wherein R ₁ and n are as described above.

In the acrylic resin for pigment dispersion according to the present invention, a long-chain amine-modified hydroxyl monomer represented by the formula (1) in which ring-opening reaction of glycidyl methacrylate or glycidyl acrylate with dialkylamino alkylamine and ε-capro Compatibility by containing a long chain primary hydroxyl monomer, a short chain hydroxyl monomer, a short chain amine monomer, and a general-purpose acrylic monomer represented by the formula (2) in which lactone is ring-opened with hydroxyethyl methacrylate or hydroxyethyl acrylate This is excellent and can improve pigment dispersibility, paint storage property, and appearance.

In addition, in order to further improve pigment dispersibility, a pigment dispersant is used. The paint containing the resin and the dispersing agent is also excellent in weather resistance, crack resistance, water resistance and the like, there is an effect suitable for automotive top coat.

The amine used in the long-chain amine-modified hydroxyl monomer represented by the formula (1) contained in the pigment dispersible acrylic resin composition of the present invention is diethylaminoethylamine, diethylaminopropylamine, diethylaminobutylamine, dipropyl Aminoethylamine, dipropylaminopropylamine, dipropylaminobutylamine, dibutylaminoethylamine, dibutylaminopropylamine, dibutylaminobutylamine. The amine may be ring-opened with glycidyl methacrylate or glycidyl acrylate to obtain a compound represented by Chemical Formula 1.

More specifically, the amine-modified hydroxyl monomer is prepared by adding an amine group and an epoxy group in a 1: 1 molar ratio in a four neck flask and reacting at 50 to 90 ° C. until no epoxy equivalent is detected. The prepared long chain amine group improves pigment dispersibility and paint storage ability.

The long chain amine-modified hydroxyl acrylic monomer represented by such a general formula (1) is contained in 3-10 weight% in an acrylic resin composition. If the content is less than 3% by weight, the pigment dispersibility and paint storage property is inferior, and if the content exceeds 10% by weight, poor chemical resistance and weather resistance due to insufficient curing.

In addition, the ε-caprolactone modified long-chain primary hydroxyl monomer represented by the formula (2) serves to improve the reaction rate, crack resistance and scratch resistance of the crosslinking. It is preferable that such (epsilon) -caprolactone modified long chain primary hydroxyl monomer is contained in an acrylic resin composition at 10-30 weight%. If the content is less than 10% by weight, crack resistance and scratch resistance are inferior, and if the content is more than 30% by weight, the cured coating film is soft, so that hardness and solvent resistance are weak.

It is preferable that the short chain hydroxyl monomer, short chain amine monomer, and general purpose acrylic monomer used in the present invention together with the compounds represented by the formulas (1) and (2) satisfy the following resin physical properties.

First, the hydroxyl value of the resin is preferably in the range of 50 to 150 mgKOH / g, preferably 70 to 130 mgKOH / g. If less than 50 mgKOH / g cross-linking density is lowered, hardness, chemical resistance, corrosion resistance is lowered, if it exceeds 150 mgKOH / g cross-linking density is high, crack resistance, chipping resistance and the like.

Short-chain hydroxyl monomers that can be used here are 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl Acrylates. Such hydroxyl monomer contains 15-30% by weight in the acrylic resin.

Second, the amine number of the resin is 5-30 mg KOH / g. If the amine value is less than 5 mg KOH / g, the pigment dispersibility and paint storage property is inferior, if it exceeds 30 mg KOH / g, there is a problem that the curing rate is poor and the appearance and chemical resistance is weak.

Short chain amine monomers that can be used here include N, N-dimethylaminoethyl methacrylate, N, N-dimethylaminoethyl acrylate, N, N-diethylaminoethyl methacrylate, and N, N-diethyl Aminoethyl acrylate, N, N-diethylaminopropyl methacrylate, N, N-diethylaminopropyl acrylate, t-butylaminoethyl methacrylate, t-butylaminoethyl acrylate and the like can be used. Such an amine monomer is contained in 1 to 5 weight% in an acrylic resin.

Third, the glass transition temperature of the acrylic resin is to have a range of -40 ~ 10 ℃. If the glass transition temperature is less than -40 ℃, the coating film is too soft, the hardness and chemical resistance falls, and if it exceeds 10 ℃ crack resistance is poor. Such acrylic monomers include methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, n-butyl methacrylate, n-butyl acrylate, t-butyl methacrylate, t-butyl acrylate, 2 Ethylhexyl methacrylate, 2-ethylhexyl acrylate, lauryl methacrylate, lauryl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, styrene monomer, benzyl methacrylate, benzyl acrylate, phenyl meth Acrylate, phenyl acrylate and the like can be used. Such an acrylic monomer is contained in 25 to 71 weight% in an acrylic resin.

As described above, an acrylic resin for dispersing a pigment containing a compound represented by Chemical Formulas 1 and 2, a short chain hydroxyl monomer, a short chain amine monomer, and a general acrylic monomer is prepared by a solution polymerization method. And isothermal reactions may also be carried out.

In addition, in order to produce a high solid paint, it is preferable that the solid content of the resin is 60 to 80% during polymerization. And it is good to superpose | polymerize by adjusting the initiator and reaction temperature so that the weight average molecular weight of resin may be in the range of 3,000-20,000. If the weight average molecular weight is less than 3,000, the pigment dispersion stability is poor, and the paint storage and chemical resistance are lowered. If the weight average molecular weight is more than 20,000, the resin compatibility is poor and the pigment dispersibility is deteriorated.

Initiators used in the polymerization of acrylic resins include 2,2-azobisisobutyronitrile, 1,1-azobiscyclohexane-1-carbonitrile, 2,2-azobis-2-methylbutyronitrile, 2 Azo compounds such as, 2-azobis-2,4-dimethylvaleronitrile, dimethyl-2,2-azobisisobutylate, and benzoyl peroxide, t-butylperoxybenzoate, di-t-butylperoxide , Dicumyl peroxide, t-amyl peroxide, t-butyl peroxy acetate, t-butyl hydroperoxide, cumene hydroperoxide, t-butyl peroxy pivalate, t-butyl peroxy-2-ethylhexano A peroxide-based organic initiator such as Eate is used, and it is preferable to use 0.1 to 10 parts by weight with respect to 100 parts by weight of the acrylic resin composition.

Examples of the solvent used in the polymerization of the resin include hydrocarbon solvents such as toluene and xylene, acetates such as acetyl acetate, n-butyl acetate, isobutyl acetate, and methoxypropyl acetate, alcohols such as n-butanol and isobutanol, and the like. It can be used alone or in combination.

A pigment dispersant is used to further improve the dispersibility of the acrylic resin for pigment dispersion thus developed. In this case, as the dispersant, metal oleates such as phenylenediamine, barium oleate, calcium oleate and magnesium oleate or metal octoates such as barium octoate, magnesium octoate and capperoctoate can be used. The usage-amount is 0.5-2.5 weight part in pigment amount.

In addition, the acrylic resin for pigment dispersion developed as described above is compatible with additives such as melamine resin, a curing agent, a leveling agent, a UV absorber and a light stabilizer, and a rheology control agent, a curing catalyst, and a dispersant, which are used for automotive coatings. This is good and is effective in dispersing oil and inorganic pigments, especially carbon black.

In the method of preparing a paint by dispersing a pigment using the acrylic resin of the present invention prepared above, a paste is prepared, and then various additives are added thereto to prepare a paint for automotive top coat. That is, in order to effectively disperse the pigment, the mill base formulation is dispersed with acrylic resin alone. This is because dispersion and dispersion stability are superior to those of melamine resin alone or a mixture of acrylic resin and melamine resin. after that ?? Stabilize with acrylic / melamine resins in the Down Down formulation.

A ball mill, a paint shake, a sand mill, etc. can be used as a pigment dispersing apparatus. In addition, the paint may be supplemented with a leveling agent, an ultraviolet absorber and a light stabilizer to supplement physical properties of the paint.

The coating method of this coating is to harden by baking the transparent coating in a wet-on-wet method using air coating, vacuum coating, electrostatic coating, and the like. At this time, the curing temperature is in the range of 120 to 180 ° C, and the curing time is adjusted to 10 to 40 minutes.

The paint prepared using the paste in which the pigment is dispersed using the acrylic resin according to the present invention is excellent in appearance, paint storage property, crack resistance, weather resistance, chemical resistance, water resistance, etc., of sunscreen and clearness.

Although this invention is demonstrated in detail based on an Example, this invention is not limited to an Example.

<Preparation of long chain amine modified hydroxyl monomer represented by Formula 1>

Preparation Example 1

130 parts by weight of diethylaminopropylamine and 142 parts by weight of glycidyl methacrylate were heated to 70 ° C. for 5 hours in a four-necked flask, and reacted for 5 hours until no epoxy equivalent was detected. Then, 116 parts by weight of butyl acetate was added. To obtain a long chain amine-modified hydroxyl monomer represented by the formula (1) having a solid content of 70%, viscosity P by a Gardner viscometer.

Preparation Example 2

186 parts by weight of dibutylaminopropylamine and 142 parts by weight of glycidyl methacrylate were heated to 80 ° C. for 5 hours in a four-necked flask, and reacted for 5 hours until no epoxy equivalent was detected. Then, 140 parts by weight of butyl acetate was added. To obtain a long chain amine-modified hydroxyl monomer represented by the formula (1) having a solid content of 70%, viscosity R by a Gardner viscometer.

Preparation Example 3

Into a four-necked flask, 116 parts by weight of diethylaminoethylamine and 128 parts by weight of glycidyl acrylate were heated at 60 ° C. for 5 hours to react until no epoxy equivalent was detected, and then 104 parts by weight of butyl acetate was added thereto. A long chain amine-modified hydroxyl monomer represented by the formula (1) having a solids content of 70% and a viscosity N in a Gardner viscometer was obtained.

<Production of Acrylic Resin for Pigment Dispersion>

Example 1

261 parts by weight of xylene was added to a four neck flask and refluxed. Then, 175 parts by weight of styrene monomer, 140 parts by weight of lauryl methacrylate, 126 parts by weight of n-butyl acrylate 140 parts by weight of PLACELL (Dacel Chemical Industries, Ltd., FA-2), the monomer prepared in Preparation Example 1 80 parts by weight, 63 parts by weight of 2-hydroxyethyl acrylate and 35 parts by weight of 2,2-azobis-2-methylbutyronitrile were dissolved and added dropwise for 3 hours, and then maintained for 2 hours. The reaction was terminated by dissolving 1.4 parts by weight of 2,2-azobis-2-methylbutyronitrile in 30 parts by weight of xylene, followed by dropwise addition for 10 minutes, and then maintaining the solution for 2 hours.

The obtained acrylic resin had a solids content of 70%, a Gardner viscometer of viscosity X, a hydroxyl value of 100 mgKOH / g, an amine of 29 mgKOH / g, a glass transition temperature of -15 ° C, and a weight average molecular weight of 10,000.

Example 2

276 parts by weight of xylene was added to a four neck flask and refluxed. Then, 175 parts by weight of methyl methacrylate, 105 parts by weight of n-butyl acrylate, 154 parts by weight of n-butyl methacrylate, 70 parts by weight of PLACELL (Dacel Chemical Industries, Ltd., FA-2), 2-hydroxy 140 parts by weight of ethyl acrylate, 30 parts by weight of the monomer prepared in Preparation Example 2, 35 parts by weight of diethylaminoethyl methacrylate, and 35 parts by weight of benzoyl peroxide were added dropwise for 3 hours, and then maintained for 2 hours. 1.4 parts by weight of benzoyl peroxide was dissolved in 30 parts by weight of xylene, followed by dropwise addition for 10 minutes, and the reaction was terminated by cooling to room temperature for 2 hours.

The obtained acrylic resin had a solids content of 70%, a Gardner viscometer of viscosity Y, a hydroxyl value of 112 mgKOH / g, an amine value of 20 mgKOH / g, a glass transition temperature of -20 ° C, and a weight average molecular weight of 12,000.

Example 3

261 parts by weight of xylene was added to a four neck flask and refluxed. Then 105 parts by weight of styrene monomer, 91 parts by weight of n-butyl methacrylate, 140 parts by weight of 2-ethylhexyl acrylate 140 parts by weight of PLACELL (Dacel Chemical Industries, Ltd., FA-2), prepared in Preparation Example 3 80 parts by weight of one monomer, 168 parts by weight of 2-hydroxyethyl acrylate, and 35 parts by weight of benzoyl peroxide were dissolved and added dropwise for 3 hours, and then maintained for 2 hours. The reaction was terminated by dissolving 1.4 parts by weight of benzoyl peroxide in 30 parts by weight of xylene, followed by dropwise addition for 10 minutes, and then maintaining the solution for 2 hours.

The obtained acrylic resin had a solids content of 70%, a Gardner viscometer of viscosity Z1, a hydroxyl value of 150 mgKOH / g, an amine value of 40 mgKOH / g, a glass transition temperature of -20 ° C, and a weight average molecular weight of 14,000.

Example 4

261 parts by weight of xylene was added to a four neck flask and refluxed. Then 175 parts by weight of methyl methacrylate, 126 parts by weight of n-butyl methacrylate, 140 parts by weight of PLACEL (DICEL Chemical Industry Co., Ltd., FA-2), 80 parts by weight of monomer prepared in Preparation Example 1, 2 -63 parts by weight of hydroxyethyl acrylate, 140 parts by weight of ethyl methacrylate, and 35 parts by weight of benzoyl peroxide were added dropwise for 3 hours, and then maintained for 2 hours. 1.4 parts by weight of benzoyl peroxide was dissolved in 30 parts by weight of xylene, followed by dropwise addition for 10 minutes, and the reaction was terminated by cooling to room temperature for 2 hours.

The obtained acrylic resin had a solids content of 70%, a Gardner viscometer of viscosity Z2, a hydroxyl value of 100 mgKOH / g, an amine of 30 mgKOH / g, a glass transition temperature of 20 ° C, and a weight average molecular weight of 15,000.

Example 5

276 parts by weight of xylene was added to a four neck flask and refluxed. Then 175 parts by weight of styrene monomer, 154 parts by weight of n-butyl methacrylate, 105 parts by weight of n-butyl acrylate 70 parts by weight of PLACELL (Dacel Chemical Industries, Ltd., FA-2), prepared in Preparation Example 2 30 parts by weight of monomer, 140 parts by weight of 2-hydroxyethyl acrylate, 35 parts by weight of dimethylaminoethyl methacrylate, and 35 parts by weight of di-t-butylperoxide were dissolved and added dropwise for 3 hours, and then maintained for 2 hours. The reaction was terminated by dissolving 1.4 parts by weight of di-t-butylperoxide in 30 parts by weight of xylene, followed by dropwise addition for 10 minutes, and maintaining the solution for 2 hours.

The obtained acrylic resin had a solids content of 70%, a Gardner viscometer of viscosity Z4, a hydroxyl value of 112 mgKOH / g, an amine of 23 mgKOH / g, a glass transition temperature of -19 ° C, and a weight average molecular weight of 28,000.

Comparative Example 1

285 parts by weight of xylene was added to a four neck flask and refluxed. Then, 175 parts by weight of styrene monomer, 140 parts by weight of lauryl methacrylate, 154 parts by weight of butyl acrylate 140 parts by weight of PLACELL (Dacel Chemical Industries, Ltd., FA-2), 28 parts by weight of acrylic acid, 2-hydroxy 63 parts by weight of ethyl acrylate and 35 parts by weight of 2,2-azobis-2-methylbutyronitrile were dissolved and added dropwise for 3 hours, and then maintained for 2 hours. The reaction was terminated by dissolving 1.4 parts by weight of 2,2-azobis-2-methylbutyronitrile in 30 parts by weight of xylene, followed by dropwise addition for 10 minutes, and then maintaining the solution for 2 hours.

The obtained acrylic resin had a solids content of 70%, a Gardner viscometer of viscosity Z1, a hydroxyl value of 100 mgKOH / g, an amine of 29 mgKOH / g, a glass transition temperature of -20 ° C, and a weight average molecular weight of 11,000.

Comparative Example 2

276 parts by weight of xylene was added to a four neck flask and refluxed. Then 196 parts by weight of methyl methacrylate, 133 parts by weight of n-butyl acrylate, 154 parts by weight of n-butyl methacrylate, 30 parts by weight of the monomer prepared in Preparation Example 2, 35 weight of diethylaminoethyl methacrylate Then, 161 parts by weight of 2-hydroxyethyl acrylate and 35 parts by weight of benzoyl peroxide are dissolved and added dropwise for 3 hours, and then maintained for 2 hours. 1.4 parts by weight of benzoyl peroxide was dissolved in 30 parts by weight of xylene, followed by dropwise addition for 10 minutes, and the reaction was terminated by cooling to room temperature for 2 hours.

The obtained acrylic resin had a solids content of 70%, a Gardner viscometer of viscosity Z, a hydroxyl value of 112 mgKOH / g, an amine of 20 mgKOH / g, a glass transition temperature of -20 ° C, and a weight average molecular weight of 13,000.

Experimental Example: Production of Paint Paste and Paint

Next, after preparing for 10 hours in a ball mill with a mill base (Mill Base) formulation shown in Table 1, ?? A paste was prepared by stirring for 2 hours using a high speed stirrer in a LET DOWN formulation.

(Unit: parts by weight) Example Resin Comparative resin Melamine solvent Acrylic resin Dispersant Pigment One 2 3 4 5 One 2 Paste 1 Mill base 200 200 50 Let down 150 100 300 Paste 2 Mill base 200 200 50 Let down 150 100 300 Paste 3 Mill base 200 200 50 Let down 150 100 300 Paste 4 Mill base 200 200 50 Let down 150 100 300 Paste 5 Mill base 200 200 50 Let down 150 100 300 Paste 6 Mill base 200 200 50 Let down 150 100 300 Paste 7 Mill base 200 200 50 Let down 150 100 300 Paste 8 Mill base 150 50 200 Let down 50 100 100 300 Paste 9 Mill base 200 199 One 50 Let down 150 100 300 (1) Melamine: methoxy melamine (CYMEL 300, Cytec Co., Ltd.) (2) solvent: xylene / butyl acetate = 1/1 (3) acrylic main resin: Koryo Chemical Co., Ltd. R5457 (4) Dispersant: barium Octoate (5) Pigment: carbon black (Degussa company FW200)

After the paste was prepared as described above, the coating was prepared by adding acrylic resin, melamine resin, leveling agent, UV absorber, rheology control agent, solvent, paste, and catalyst in the order of coating formulation as shown in Table 2 below. . However, the raw materials were added while stirring with a stirrer. The use amount of paste is 300 weight part.

(Unit: parts by weight) Acrylic resin Melamine Leveling agent UV absorbers Rheology modifier solvent Paste catalyst Paint 1 200 70 One 1.5 300 117.5 Paste 1 10 Paint 2 Paste 2 Paint 3 Paste 3 Paint 4 Paste 4 Paint 5 Paste 5 Paint 6 Paste 6 Paint 7 Paste 7 Paints 8 Paste 8 Paint 9 Paste 9 (1) Acrylic resin resin: Korea Chemical Co., Ltd. R5457 (2) Melamine resin: Cytec, CYMEL 300 (3) Leveling agent: Japan Kusmoto, LC 900 (4) UV absorber: Ciba-Geigy Tinuvin 1130 (5) Rheology regulator: Cellulose acetate butyrate (CAB) 551-0.01SEC (Eastmann's product) dissolved in butyl acetate = 30/70 (6) Solvent: xylene / methanol = 80 / 20 (7) Paste: Paste prepared according to Table 1 (8) Catalyst: NACURE 195 (manufactured by King)

After the paint prepared according to Table 2 was adjusted to 16 sec at Ford-Cup (25 ° C.) on a specimen coated with an electrodeposition and a medium, it was coated with 20 to 25 μm, and the transparent paint was wet-on-wet. The coating was baked and baked at 150 ° C for 30 minutes to evaluate the physical properties.

The evaluated physical properties are shown in Table 3 below.

Here, the evaluation method of the physical property is as follows.

1) Pigment dispersibility: Mix with paint stock / white paint = 100/10

2) Paint storage property: After storage at 60 ℃ for 3 days

3) Appearance (Seonyoung Sung): measured with a tention meter

4) Gloss: measured by BYK Micro-Tree-Gross Meter

5) Chipping resistance: measured at -40 ℃ for 3 hours and then measured

6) Weather resistance: QUV device manufactured by Q-Panel Co., Ltd.

7) Water resistance: After 10 days of storage at 40 ℃, discoloration of the coating and the presence of Blister

Paint name One 2 3 4 5 6 7 8 9 Pigment Dispersibility ○ + ○ + ○ + ○ + △ △ ○ + △ + ◎ Paint Storage ◎ ◎ ◎ ○ + △ △ ○ + ○ ◎ Appearance 17 17 17- 17- 17- 17- 17 17 17 Glossy (60 °) 94 94 92 93 91 93 92 92 94 Chipping resistance 7+ 7+ 7 7- 7 7 7- 7 7+ Weather resistance (2000 hours) ◎ ◎ △ ○ ○ ○ ○ ○ ◎ Water resistance ◎ ◎ △ ◎ ○ ○ ○ ○ ◎ ◎: Very good, ○ +: Slightly good, ○: Excellent, △ +: Good, △: Normal

As described in detail above, the pigment dispersion acrylic resin according to the present invention can improve the crosslinking reaction rate, pigment dispersibility, paint storage property, and excellent compatibility, paints containing it are goodness, clearness, etc. It has excellent appearance, crack resistance, weather resistance, chemical resistance, water resistance, etc., and is suitable as a top coat for automobiles.

Claims (5)

Next, 3 to 10% by weight of the long-chain amine-modified hydroxyl monomer represented by the following formula (1), 10 to 30% by weight of the ε-caprolactone-modified long-chain primary hydroxyl monomer represented by the following formula (2), 15 to 15 short-chain hydroxyl monomer An acrylic resin composition for pigment dispersion containing 30% by weight, 1 to 5% by weight of short chain amine monomer and 25 to 71% by weight of general purpose acrylic monomer. Formula 1 Wherein R ₁ is a hydrogen atom or a methyl group, R ₂ is an alkyl group having 2 to 4 carbon atoms, and n is an integer of 2 to 4; Formula 2 Wherein R ₁ and n are as described above. The compound represented by the formula (1) is diethylaminoethylamine, diethylaminopropylamine, diethylaminobutylamine, dipropylaminoethylamine, dipropylaminopropylamine, dipropylaminobutylamine, di Acrylic resin composition for pigment dispersion, characterized in that it is obtained by ring-opening reaction of an amine selected from the group consisting of butylaminoethylamine, dibutylaminopropylamine and dibutylaminobutylamine with glycidyl methacrylate or glycidyl acrylate. . The acrylic resin composition for pigment dispersion according to claim 1, wherein the acrylic resin has a weight average molecular weight of 3,000 to 20,000. The acrylic resin composition according to claim 1, wherein the acrylic resin has a hydroxyl value of 50 to 150 mgKOH / g, an amine value of 5 to 30 mgKOH / g, and a glass transition temperature of -40 to 10 ° C. A coating composition containing the acrylic resin composition of claim 1 and a dispersant selected from the group consisting of phenylenediamine, metal oleate and metal octoate.