KR101669835B1 - One-component type paint composition comprising silane acrylic resin as main resin component - Google Patents

Abstract

The present invention relates to a one-pack coating composition containing a silane acrylic resin as a main resin component, and more particularly to a one-pack coating composition comprising a silane acrylic resin as a main resin component and an acrylic polyol resin having a lactone-derived aliphatic linear structure The present invention relates to a one-pack coating composition suitable as a one-pack type clearcoat for automobiles, which can exhibit physical properties equivalent to physical properties of a coating obtained under conventional baking conditions even when cured by a low temperature baking.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a one-pack coating composition containing a silane acrylic resin as a main resin component.

The present invention relates to a one-pack coating composition comprising a silane acrylic resin as a main resin component, and more particularly to a one-pack coating composition having a silane acrylic resin as a main resin component and a lactone-derived aliphatic linear structure The present invention relates to a one-pack coating composition which is particularly suitable as a one-pack type clearcoat for automobiles, because it can exhibit physical properties equivalent to the physical properties of a coating obtained under conventional baking conditions even when cured with a low temperature baking.

Most of the energy used in automobile production plants is consumed in the paint booths and ovens of the painting factory. In recent years, the automotive industry has been demanding the development of paints that can be cured at low temperature, since the oven power consumed at the painting factory can be reduced if low-temperature baking is possible.

An acrylic resin mixture capable of low temperature baking has been disclosed (for example, Japanese Patent No. 3929515 and Japanese Patent No. 3249053), which corresponds to a two-pack type paint using isocyanate as a curing agent. Further, although a technique using an acid / epoxy-containing resin has been disclosed (for example, US Patent No. 5369178), there is a problem that the effective period of the paint is limited when it is used as a one-pack type paint.

Accordingly, development of a coating composition for automobiles that can be used at low temperatures and which can be used as a one-pack coating material is desired.

Disclosure of the Invention The present invention has been made to solve the problems of the prior art as described above, and it is an object of the present invention to provide a coating composition comprising a silane acrylic resin as a main resin and a lactone- The present invention also provides a one-pack coating composition suitable for use as a one-pack type clearcoat for automobiles, which can exhibit physical properties equivalent to physical properties of a coating obtained under conventional baking conditions even when cured with a low temperature baking.

(1) 35 to 90 parts by weight of a main silane acryl resin containing an alkoxysilane functional group, (2) 3 to 30 parts by weight of an acrylic polyol auxiliary resin (3) 5 to 40 parts by weight of a melamine curing agent, and (4) 0.01 to 10 parts by weight of a curing catalyst, wherein the acrylic polyol auxiliary resin comprises 10 to 50 parts by weight of a lactone modified acrylate oligomer 10 to 80 parts by weight of an ethylenically unsaturated monomer, and 0.1 to 15 parts by weight of an initiator, wherein the lactone-modified acrylate oligomer has a ring having 4 to 8 carbon atoms per 1 mole of an ethylenically unsaturated monomer containing a hydroxyl group Ring-opening polymerization using 1 to 5.5 moles of a lactone compound having a carbon atom to obtain a lactone-derived aliphatic linear structure and a polyfunctional hydroxyl group By weight, based on the total weight of the coating composition.

According to another aspect of the present invention, there is provided a molded article comprising at least one coating layer formed from the one-pack coating composition.

The one-pack coating composition according to the present invention can exhibit the same physical properties as those of the coating film obtained under the existing baking conditions even when cured with a low-temperature baking, and is particularly suitable as a one-pack type clearcoat for automobiles.

Hereinafter, the present invention will be described in more detail.

The one-pack coating composition of the present invention comprises a silane acrylic resin as a main resin component. The silane acrylic resin usable in the present invention preferably has a solid content of 40 to 80% by weight and a hydroxyl value of 30 to 200 mgKOH on the basis of the solid content.

The silane acrylic resin can be produced by polymerizing an ethylenically unsaturated monomer or an alkoxysilane compound as a monomer component in the presence of a conventional initiator in a solvent used for producing a general acrylic resin.

The ethylenically unsaturated monomer may be selected from the group consisting of styrene, methyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tertiary butyl (Meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, lauryl (meth) acrylate, and combinations thereof.

Although not particularly limited, the alkoxysilane compound is an alkoxysilane group in which one or more vinyl groups, acrylic groups, and methacrylic groups are substituted, and the alkoxysilane compound includes vinyltrimethoxysilane, vinyltriethoxysilane, vinylbutyltriethoxysilane , Vinyltri (beta-methoxy) silane, vinyltri (beta-ethoxy) silane, acryloxypropyltrimethoxysilane, acryloxypropyltriethoxysilane, acryloxypropylmethyldimethoxysilane, gamma-methacryloxy Methacryloxypropylmethyldimethoxysilane, and gamma-methacryloxypropylmethyldiisopropoxysilane, gamma-glycidyloxypropyltriazine, gamma-glycidyloxypropyltrimethoxysilane, gamma-methacryloxypropyltrimethoxysilane, Methoxysilane, and gamma-glycidyloxypropyltriethoxysilane, and combinations thereof.

Although not specifically limited, the hydroxyl-containing monomers include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, allyl alcohol and methacryloyl And combinations thereof.

The solvent is not particularly limited and includes, for example, aromatic hydrocarbon solvents such as toluene and xylene; Ketone solvents such as methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone and ethyl propyl ketone; Ester solvents such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, isopropyl, butyl acetate and butyl cellosolve acetate; And combinations thereof.

Although not particularly limited, examples of the initiator include 2,2'-azobis (2-methylbutylonitrile), 2,2'-azobisisobutyronitrile, dibenzoyl peroxide, tertiary butyl peroxybenzoate, Butylperoxy-2-ethylhexanoate, tertiary butyl peroxyacetate, tertiary amyl peroxy-2-ethyl hexanoate, di-tertiary amyl peroxide, cumyl hydroperoxide, Dicumyl peroxide, and combinations thereof.

The one-pack coating composition of the present invention contains silane acrylic resin as a main resin component in an amount of 35 to 90 parts by weight, more preferably 40 to 80 parts by weight, based on 100 parts by weight of the total composition. If the amount of the silane acrylic resin in 100 parts by weight of the composition is less than 35 parts by weight, the mechanical properties may deteriorate. If the amount is more than 90 parts by weight, workability, appearance and flowability are deteriorated.

The one-pack coating composition of the present invention comprises an acrylic polyol resin as an auxiliary resin component. The acrylic polyol resin is prepared by polymerizing 10 to 80 parts by weight of a lactone-modified acrylate oligomer, 10 to 80 parts by weight of an ethylenically unsaturated monomer, and 0.1 to 15 parts by weight of an initiator based on 100 parts by weight of a monomer in the resin, The oligomer is subjected to cyclic ring polymerization using 1 to 5.5 mol of a lactone compound having a ring carbon atom of 4 to 8 carbon atoms per mol of the ethylenically unsaturated monomer containing a hydroxyl group to obtain a lactone-derived aliphatic linear structure and a polyfunctional hydroxyl And a real machine.

The lactone-modified acrylate oligomer used in the polymerization of the acrylic polyol resin may have a lactone-derived aliphatic linear structure and a polyfunctional hydroxyl group by ring-opening polymerization using a lactone compound.

Here, the lactone-modified acrylate oligomer refers to a lactone compound which is a heterocyclic compound containing -COO- in a molecule and is subjected to ring opening polymerization by reacting an acrylate monomer containing a hydroxy group to link a polymerizable double bond and a hydroxy group And the carbon structure in which the linear element has a single bond is repeated.

 The lactone compound is not particularly limited as long as it can impart a lactone-derived aliphatic linear structure and a polyfunctional hydroxyl group to the lactone-modified acrylate oligomer of the present invention, but is not limited to ε-caprolactone, β-methyl- Lactone,? -Caprolactone,? -Caprolactone,? -Butyrolactone, and combinations thereof.

As described above, the ring-opening polymerization can be carried out using the lactone compound. In this case, a catalyst for ring-opening polymerization can be further included. The catalyst may be used in an amount of up to 1000 ppm based on the total weight of the lactone-modified acrylate oligomer. The catalyst is not particularly limited as long as it can be used as a catalyst in the ring-opening polymerization, and tin compounds, organic lead or manganese compounds are preferable, and specific examples include tetraphenyl tin, tetraoctyl tin, diphenyl tin laurate, dimethyl tin Oxide, dibutyltin oxide, lead acetate or magnesium acetate.

In order to polymerize the lactone-modified acrylate of the present invention, 1 to 5.5 mol of a lactone compound having a ring carbon atom of 4 to 8 carbon atoms can be used per 1 mol of the ethylenically unsaturated monomer containing a hydroxyl group.

Specifically, when less than 1 mole of the lactone compound is used, a large amount of residual hydroxy groups may remain to participate in the curing reaction. If it exceeds 5.5 moles, hardness may be lowered because there are few sites capable of curing reaction with the curing agent , Moisture resistance, weather resistance, chemical resistance, and the like.

In order to polymerize the acrylic polyol resin of the present invention, the polymerized lactone modified acrylate oligomer may be used in an amount of 10 to 80 parts by weight based on 100 parts by weight of the monomer in the resin. When the amount is less than 10 parts by weight, a desired effect can not be expected. When the amount is more than 80 parts by weight, hardness is lowered due to few sites capable of undergoing a curing reaction with the curing agent, which can lower the moisture resistance, weather resistance, It is not preferable.

The acrylic polyol resin used in the present invention is not particularly limited, but has a weight average molecular weight of 5,000 to 30,000, a resin solid content of 40 to 90% by weight, and a hydroxyl value of 80 to 200 mgKOH on a solid weight basis.

In order to polymerize the acrylic polyol resin of the present invention, 10 to 80 parts by weight of the ethylenically unsaturated monomer may be used based on 100 parts by weight of the monomer in the resin. When the amount of the ethylenically unsaturated monomer is less than 10 parts by weight, the content of the lactone-modified acrylate oligomer is excessively large, and excessive use of the curing agent and the curing catalyst is inevitable, so that it may be difficult to secure mechanical properties. On the other hand, if the amount of the ethylenically unsaturated monomer exceeds 80 parts by weight, it is difficult to exert the effect of improving the reactivity of the resin, which is not preferable.

The ethylenically unsaturated monomer may be selected from the group consisting of styrene, methyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tertiary butyl (Meth) acrylate, benzyl (meth) acrylate, isobonyl (meth) acrylate, lauryl (meth) acrylate, and combinations thereof.

An initiator may be used to polymerize the acrylic polyol resin of the present invention, and the initiator may be used in an amount of 0.1 to 15 parts by weight based on 100 parts by weight of the monomer in the resin.

The initiator is not particularly limited as long as it can initiate a chain reaction. Examples of the initiator include 2,2 'azobis (2-methylbutylonitrile), 2,2' azobisisobutylonitrile, dibenzoyl peroxide, Peroxy benzoate, ditertiary butyl peroxide, tertiary butyl peroxy-2-ethyl hexanoate, tertiary butyl peroxyacetate, tertiary amyl peroxy-2-ethyl hexanoate, ditertiary amyl peroxide, Cumyl hydroperoxide, dicumyl peroxide, and combinations thereof.

In addition, a chain transfer agent may be further included for controlling the molecular weight, and the chain transfer agent may be contained in an amount of 10 parts by weight or less based on the total weight. Examples of the chain transfer agent include lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, 2,3-dimercapto- Phenol, and the like, or combinations thereof.

The solvent which can be used for polymerizing the acrylic polyol resin of the present invention is not particularly limited so long as it does not adversely affect the reaction, and examples thereof include aromatic hydrocarbon solvents such as toluene and xylene; Ketone solvents such as methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone and ethyl propyl ketone; Ester solvents such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, isopropyl, butyl acetate and butyl cellosolve acetate; And combinations thereof. Preferably, the solvent may be used in an amount of 10 to 60 parts by weight based on 100 parts by weight of the ethylenically unsaturated monomer.

The one-pack coating composition of the present invention comprises a melamine curing agent. Although not particularly limited, the melamine curing agent may be selected from hexamethylol melamine, hexamethoxymethyl melamine, hexabutoxymethyl melamine, and combinations thereof.

The one-pack coating composition of the present invention contains a melamine curing agent in an amount of 5 to 40 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the total composition. The amount of the melamine curing agent in 100 parts by weight of the composition. Outside of the above range, the mechanical properties may be deteriorated.

The one-pack coating composition of the present invention comprises a curing catalyst. Although not particularly limited, the curing catalyst may be selected from dodecylbenzenesulfonic acid, sulfonic acid, dinonylnaphthalene disulfonic acid, dinonylnaphthalenesulfonic acid, and combinations thereof.

The one-pack coating composition of the present invention contains the curing catalyst in an amount of 0.01 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the total weight of the composition. If the amount of the curing catalyst in 100 parts by weight of the composition is out of the above range, the mechanical properties may be deteriorated.

In addition to the above components, the coating composition of the present invention may contain a solvent. The solvent is not particularly limited and includes, for example, aromatic hydrocarbon solvents such as toluene and xylene; Ketone solvents such as methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone and ethyl propyl ketone; Ester solvents such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, isopropyl, butyl acetate and butyl cellosolve acetate; And combinations thereof. The content of the solvent in the coating composition is not particularly limited. For example, 5 to 100 parts by weight of the solvent may be used based on 100 parts by weight of the solid content in the coating composition, but not limited thereto.

In addition, the coating composition of the present invention may further comprise a leveling agent, a light stabilizer, a flow control agent, a defoaming agent, a hygroscopic agent, and a combination thereof.

According to another aspect of the present invention, there is provided a molded article comprising at least one coating layer formed from the coating composition. The molded article may be a metal or a non-metal material, for example, an automobile part.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the scope of the present invention is not limited thereto.

[ Example ]

Synthetic example  1-1: Lactone modification Acrylate Oligomeric  Produce

103 g of coco sol # 100 and 206 g of hydroxyethyl acrylate were charged into a four-necked flask for synthesis having a thermometer and a stirrer, and the temperature was raised to 80 ° C. After the temperature was stabilized, 203 g of epsilon caprolactone was introduced and the temperature was raised to 130 ° C. After the reaction was maintained for 3 hours, the reaction solution was cooled to 60 DEG C to obtain a lactone-modified acrylate oligomer having a solid content of 80%.

Synthetic example  1-2: lactone modification Acrylate Oligomer  Acrylic applied Polyol  Preparation of Resin (A)

103 g of Cocosol # 100 was introduced into a four-necked flask for synthesis, equipped with a thermometer and a stirrer, and then heated to the reflux temperature. After stabilizing the reflux, 512 g of the lactone-modified acrylate oligomer prepared in Synthesis Example 1-1, 309 g of styrene monomer, 313 g of butyl acrylate, 62 g of tertiary butyl peroxybenzoate and 63 g of cocosol # 100 were uniformly reacted for 180 minutes and 195 minutes The mixture was kept at reflux for 60 minutes. Thereafter, the reaction product was diluted with coco sol # 100 and then cooled to 60 캜 to obtain an acrylic polyol resin (A) having a solid content of 70%.

Synthetic example  2-1: lactone degeneration Acrylate Oligomeric  Produce

A synthetic four-necked flask equipped with a thermometer and a stirrer was charged with 103 g of cocosol # 100 and 175 g of hydroxyethyl acrylate, and the mixture was heated to 80 ° C. After the temperature was stabilized, 518 g of epsilon caprolactone was charged and the temperature was raised to 130 ° C. After the reaction was maintained for 3 hours, the reaction solution was cooled to 60 DEG C to obtain a lactone-modified acrylate oligomer having a solid content of 87%.

Synthetic example  2-2: Lactone degeneration Acrylate Oligomer  Acrylic applied Polyol  Preparation of Resin (B)

103 g of Cocosol # 100 was introduced into a four-necked flask for synthesis, equipped with a thermometer and a stirrer, and then heated to the reflux temperature. After stabilizing the reflux, 796 g of the lactone-modified acrylate oligomer prepared in Synthesis Example 2-1, 309 g of styrene monomer, 30 g of butyl acrylate, 62 g of tertiary butyl peroxybenzoate and 63 g of cocosol # 100 were uniformly reacted for 180 minutes and 195 minutes The mixture was kept at reflux for 60 minutes. Thereafter, the reaction product was diluted with coco sol # 100 and then cooled to 60 캜 to obtain an acrylic polyol resin (B) having a solid content of 70%.

Synthetic example  3-1: Lactone degeneration Acrylate Oligomeric  Produce

A synthetic four-necked flask equipped with a thermometer and a stirrer was charged with 103 g of Cocosol # 100 and 118 g of hydroxyethyl acrylate, and the mixture was heated to 80 ° C. After the temperature was stabilized, 584 g of epsilon caprolactone was introduced and the temperature was raised to 130 degrees. After the reaction was maintained for 3 hours, the reaction solution was cooled to 60 DEG C to obtain a lactone-modified acrylate oligomer having a solid content of 87%.

Synthetic example  3-2: Lactone degeneration Acrylate Oligomer  Acrylic applied Polyol  Preparation of Resin (C)

103 g of Cocosol # 100 was introduced into a four-necked flask for synthesis, equipped with a thermometer and a stirrer, and then heated to the reflux temperature. After stabilizing the reflux, 805 g of the lactone-modified acrylate oligomer prepared in Synthesis Example 3-1, 309 g of styrene monomer, 20 g of butyl acrylate, 62 g of tertiary butyl peroxybenzoate and 63 g of cocosol # 100 were uniformly stirred for 180 minutes and 195 minutes The mixture was kept at reflux for 60 minutes. Thereafter, the reaction product was diluted with coco sol # 100 and then cooled to 60 캜 to obtain an acrylic polyol resin (C) having a solid content of 70%.

Synthetic example  4-1: Lactone degeneration Acrylate Oligomeric  Produce

103 g of coco sol # 100 and 206 g of hydroxyethyl acrylate were charged into a four-necked flask for synthesis having a thermometer and a stirrer, and the temperature was raised to 80 ° C. After the temperature was stabilized, 101 g of epsilon caprolactone was charged and the temperature was raised to 130 ° C. The reaction was maintained for 3 hours and then cooled to 60 DEG C to obtain a lactone-modified acrylate oligomer having a solid content of 75%.

Synthetic example  4-2: Lactone degeneration Acrylate Oligomer  Acrylic applied Polyol  Preparation of Resin (D)

103 g of Cocosol # 100 was introduced into a four-necked flask for synthesis, equipped with a thermometer and a stirrer, and then heated to the reflux temperature. After stabilizing the reflux, 410 g of the lactone-modified acrylate oligomer prepared in Synthesis Example 4-1, 309 g of styrene monomer, 414 g of butyl acrylate, 62 g of tertiary butyl peroxybenzoate and 63 g of cocosol # 100 were uniformly reacted for 180 minutes and 195 minutes The mixture was kept at reflux for 60 minutes. Thereafter, the reaction product was diluted with coco sol # 100 and then cooled to 60 캜 to obtain an acrylic polyol resin (D) having a solid content of 70%.

Synthetic example  5-1: Lactone degeneration Acrylate Oligomeric  Produce

103 g of cocosol # 100 and 103 g of hydroxyethyl acrylate were charged into a four-necked flask for synthesis having a thermometer and a stirrer, and the temperature was raised to 80 ° C. After the temperature was stabilized, 609 g of epsilon caprolactone was charged and the temperature was raised to 130 degrees. After the reaction was maintained for 3 hours, the reaction solution was cooled to 60 DEG C to obtain a lactone-modified acrylate oligomer having a solid content of 87%.

Synthetic example  5-2: Lactone degeneration Acrylate Oligomer  Acrylic applied Polyol  Preparation of resin (E)

103 g of Cocosol # 100 was introduced into a four-necked flask for synthesis, equipped with a thermometer and a stirrer, and then heated to the reflux temperature. After stabilizing the reflux, 815 g of the lactone-modified acrylate oligomer prepared in Synthesis Example 5-1, 309 g of styrene monomer, 10 g of butyl acrylate, 62 g of tertiary butyl peroxybenzoate and 63 g of cocosol # 100 were uniformly stirred for 180 minutes and 195 minutes The mixture was kept at reflux for 60 minutes. Thereafter, the reaction product was diluted with coco sol # 100, and then cooled to 60 캜 to obtain an acrylic polyol resin (E) having a solid content of 70%.

 Preparation of coating composition

The coating compositions of Example 1 and Comparative Examples 1 to 3 were each prepared by mixing and stirring at 1500 rpm for 20 minutes or more as shown in Table 1.

The silane acrylic resin had a weight average molecular weight of 5,000, a resin solid content of 70% by weight, and a hydroxyl value of 80 mgKOH on a solid weight basis.

The air pressure was kept constant at about 4.5 kgf / cm ² with a handgun spray having a nozzle diameter of 1.5 mm, and the distance between the nozzle inlet and the specimen was kept constant in the range of 2 to 30 cm, sec. < / RTI > The properties of the coating films (hardness, adhesion, water resistance, acid resistance, alkali resistance and solvent resistance) were measured as follows after coating and curing at 130 캜 for 20 minutes.

(1) Hardness: Measured by pencil hardness method (hardness measurement not to damage the coating film with each pencil of 3B, 2B, B, HB, F, H,

(2) Adhesion: After completion of the painting process, the coated sample is subjected to heat treatment CYCLE and left at room temperature for 24 hours. Heat treatment CYCLE is repeated three times at 150 ℃ for 20 minutes and 20 minutes at room temperature.

(3) Water resistance: The specimens were immersed in a constant temperature water bath at 40 DEG C for 240 hours, left at room temperature for 1 hour, and then subjected to peel test by sticky wood adhesion evaluation to visually observe the abnormality of the appearance. After the test, the appearance should be free of softening, whitening, gloss defects, peeling, swelling, discoloration, etc., and there should be no difference in appearance between the immersed portion and the untreated portion.

(4) Acid resistance: 0.2 mL of 0.1 N sulfuric acid was added dropwise to the specimen. Heat the Gradient Oven for 150 minutes at 35-40 ° C. The highest temperature at which damage did not occur was judged to be an acid resistance temperature by confirming the occurrence of etching, staining, and blistering by visual observation of the specimen where the sulfuric acid solution was dropped.

(5) Alkali resistance: Dissolve 2 mL of 0.1 N sodium hydroxide solution in the specimen, and heat it in oven at 55 ℃ for 4 hours. Check for any visible etching, spots or blisters on the specimens where the sodium hydroxide solution was dropped.

(6) Solvent resistance: After putting the test cloth with the test solvent (XYLENE) on the test piece, scrape 4 times with a force of 2Kg every ninety minutes to record the time when the lower layer surface appeared.

As shown in Table 2, the coating compositions of the examples of the present invention are superior in physical properties such as acid resistance, alkali resistance and solvent resistance to those of Comparative Examples 1 to 3, and have properties equivalent to those of the case of curing at the existing baking temperature Therefore, it can be seen that it can be usefully used to reduce the energy consumed in curing.

Claims (5)

With respect to 100 parts by weight of the total composition,
(1) 35 to 90 parts by weight of a silane-acrylic main resin containing an alkoxysilane functional group,
(2) 3 to 30 parts by weight of an acrylic polyol auxiliary resin,
(3) 5 to 40 parts by weight of a melamine curing agent, and
(4) 0.01 to 10 parts by weight of a curing catalyst,
Wherein the acrylic polyol auxiliary resin is prepared by polymerizing 10 to 80 parts by weight of a lactone modified acrylate oligomer, 10 to 80 parts by weight of an ethylenically unsaturated monomer, and 0.1 to 15 parts by weight of an initiator based on 100 parts by weight of a monomer in the resin, The modified acrylate oligomer is subjected to cyclic ring polymerization using 1 to 5.5 mol of a lactone compound having a ring carbon atom of 4 to 8 carbon atoms per mol of the ethylenically unsaturated monomer containing a hydroxyl group to obtain a lactone-derived aliphatic linear structure and a polyfunctional Of a hydroxyl group,
Wherein the acrylic polyol auxiliary resin has a weight average molecular weight of 5,000 to 30,000.
1-part type coating composition. The one-part coating composition according to claim 1, wherein the hydroxyl value of the main silane acryl resin is 30 to 200 mg KOH based on the solid weight. The composition of claim 1 wherein the ethylenically unsaturated monomer is selected from the group consisting of styrene, methyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) (Meth) acrylate, benzyl (meth) acrylate, isobonyl (meth) acrylate, lauryl (meth) acrylate, and combinations thereof. The lactone compound according to claim 1, characterized in that the lactone compound is selected from? -Caprolactone,? -Methyl-zeta-valerolactone,? -Caprolactone,? -Caprolactone,? -Butyrolactone and combinations thereof 1-part type coating composition. The coating composition according to claim 1, wherein the acrylic polyol resin has a resin solid content of 40 to 90% by weight and a hydroxyl value of 80 to 200 mgKOH based on the solid weight.