JPH0822994B2 - Paint composition and heat resistant paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a heat-resistant paint composition which is excellent in heat-resistant yellowing, adheres to a substrate after heat treatment, is economical, and can be cross-linked at low temperature. Heat resistant paints.

(Prior Art) Conventionally, a polyorganosiloxane resin alone or a siloxane resin modified with an acrylic, alkyd, polyester resin or the like has been used as a resin for heat-resistant paints for heating appliances, household electric appliances and the like. In recent years, there has been an increasing demand in the industry for coating films that are highly economical and have excellent heat yellowing resistance.

Polyorganosiloxane resin is excellent in heat-resistant yellowing of light-colored coating film and adhesion to substrate after heat treatment.
Baking at a high temperature of 50 to 350 ° C is required, and the economy is poor.

Silicon-modified acrylic resin and silicon-modified epoxy resin have excellent chemical resistance and corrosion resistance, but poor heat-resistant yellowing.

(Problems to be Solved by the Invention) Accordingly, the present invention provides a paint composition and a heat-resistant paint which are excellent in heat-resistant yellowing, excellent in adhesion to a substrate after heat treatment, and excellent in economical efficiency. .

(Means for Solving the Problem) That is, the present invention is directed to an alcohol component and an aromatic dibase which are mainly composed of an aliphatic polyhydric alcohol having two to three hydroxyl groups in one molecule and having a neopentyl structure. A condensate obtained by reacting an acid component containing an acid as a main component, having a number average molecular weight of 1,000 to 4,000 and a hydroxyl value (solid content) of 250 to
A coating composition containing a siloxane-modified polyester resin obtained by reacting a polyester resin of 400 and a methylphenylpolysiloxane resin containing a silanol group, a metal chelate compound, and a curing catalyst, and the composition containing the composition. Heat resistant paint.

In the siloxane-modified polyester resin which is the main component of the coating composition of the present invention, 2 hydroxyl groups are contained in one molecule which is the main component of the polyhydric alcohol used in the polyester resin.
Examples of the aliphatic polyhydric alcohol having 3 to 3 and having a neopentyl structure include neopentyl glycol, 2,2-dimethyl 3-hydroxypropyl, trimethylolethane, trimethylolpropane, etc. More than one species can be used.

An aliphatic polyhydric alcohol, an alicyclic polyhydric alcohol or an aromatic polyhydric alcohol can be used in combination as the polyhydric alcohol component other than those mentioned above, but the amount thereof is preferably 10% by weight or less. Combined use in an amount exceeding 10% by weight tends to reduce heat yellowing.

Examples of fatty acid polyhydric alcohols that can be used in combination include ethylene glycol, pyropyrene glycol, and 2,2,4-trimethyl.
1,3-pentanediol, 3-methyl 1,5-pentanediol, 1,6-hexanediol, 2,2-diethyl-1,3-propanediol, 2-n-butyl-2-ethyl-1,3 -Propanediol, diethylene glycol, dipropylene glycol, glycerin, monoglycidyl ester of versatic acid, monoglycidyl ester of paratersialybutyl benzoic acid, etc., and alicyclic polyhydric alcohols include 1,4-cyclohexanedimethanol, Examples include spiroglycol, tris (2-hydroxyethyl) isocyanurate, hydrogenated bisphenol, and examples of the aromatic polyhydric alcohol include bisphenol A.

As the aromatic dibasic acid which is the main component of the acid component, there are phthalic acid or its anhydride, isophthalic acid, terephthalic acid, dimethyl terephthalate and the like, and one or more of these can be used. Aliphatic dibasic acids or alicyclic dibasic acids other than the above can be used in combination,
The amount is preferably 10% by weight or less. Combined use in an amount exceeding 10% by weight tends to reduce heat-resistant yellowing.

Examples of the aliphatic dibasic acid that can be used in combination include adipic acid, sebacic acid, and azelaic acid. Examples of the alicyclic dibasic acid include hexahydrophthalic acid, tetrahydrophthalic acid or its anhydride, and dimethyl-1,4-cyclohexane. Dicarboxylate etc. are mentioned.

Further, a monobasic acid such as benzoic acid or p-t-butylbenzoic acid or a polybasic acid such as trimellitic acid or an anhydride thereof may be used in combination within a range that does not impair the effects of the present invention.

The above-mentioned respective components are blended and a polyester resin is manufactured by a known manufacturing method such as a melting method or a solvent method. The number average molecular weight of the polyester resin thus obtained is adjusted to 1,000 to 4,000, preferably 1,500 to 3,000. When the number average molecular weight is less than 1,000, the physical properties after modification with a methylphenylpolysiloxane resin and the adhesion to the substrate after heat treatment are poor, and when the number average molecular weight exceeds 4,000, heat yellowing is poor.

The number average molecular weight in the present invention means a value measured by gel permeation chromatography and converted using a standard polystyrene calibration curve.

Also, the hydroxyl value (solid content) of this polyester resin
Is in the range of 250 to 400, preferably 300 to 350. If the hydroxyl value is less than 250, the stain resistance and solvent resistance are poor, and if it exceeds 400, the physical properties and the adhesion to the substrate after heat treatment are deteriorated.

The number average molecular weight and the hydroxyl value can be set within the above ranges by selecting the type of each component, determining the compounding ratio thereof, and adjusting the acid value at the time of production.

Next, the other component used in the production of the siloxane-modified polyester resin of the present invention, a silanol group-containing methylphenylpolysiloxane resin, will be described.

Generally, silanol group-containing organopolysiloxane resins include dimethylpolysiloxane, methylphenylpolysiloxane, and diphenylpolysiloxane.
The heat resistance depends on the side chain group, and the methyl group is desorbed at about 350 ° C and the phenyl group is desorbed at about 400 ° C, so those with many phenyl groups are excellent in heat yellowing. From this fact, diphenyl polysiloxane is the most excellent in heat-resistant yellowing, but it is expensive and inferior in economic efficiency. Methylphenylpolysiloxane is advantageous from the viewpoint of heat-resistant yellowing and economy, and the ratio of methyl groups to phenyl groups is preferably 60% or more.

The siloxane-modified polyester resin of the present invention comprises a polyester resin and a silanol group-containing methylphenylpolysiloxane resin, and the former / latter solid content weight ratio is preferably
It is obtained by reacting at a ratio of 90/10 to 60/40, particularly preferably at a ratio of 80/20 to 70/30. If this ratio exceeds 90/10, the heat-resistant yellowing and solvent resistance tend to be inferior, while if it is less than 60/40, the coating stability when using a metal chelate or a curing catalyst is poor and the economy is low. Tend to be inferior to.

The siloxane-modified polyester resin can be reacted by a known production method by blending the above polyester resin and methylphenylpolysiloxane resin in the above proportions. For example, 4 to 8% by weight of xylol for reflux dehydration and 0.01 to 0.5% by weight of a reaction catalyst such as tetrabutyl titanate or tetrabutylzirconium are added to the above composition at 140 to 160 ° C. It is obtained by reacting up to a predetermined dehydration amount (the amount by which 60% or more of the silanol groups of the methylphenyl polysiloxane resin is dehydrated).

The coating composition of the present invention further contains a metal chelate compound as a crosslinking reaction agent. As the metal chelate compound, at least one kind of chelate compounds such as aluminum type, titanium type and zirconium type is used. Among these chelate compounds, a chelate compound containing a compound forming a keto / enol tautomer as a ligand forming a stable chelate ring is preferable. A chelate compound obtained by reacting acetoacetic acid esters and β-diketones as a compound constituting the keto / enol tautomer is particularly preferable because it has excellent coating stability. Further, among these chelate compounds, aluminum-based or zirconium-based chelate compounds are most preferable because they are excellent in heat-resistant yellowing.

Specific metal chelate compounds include di-i-propoxy bis (acetylacetone titanate), di-n-
Butoxy bis (tri-ethanolamine) titanate, dihydroxy bis (lactic acid) titanate, tetraoctylene glycol titanate, di-i-
Titanium-based chelate compounds such as propoxy bis (ethyl acetoacetate) titanate, diisopropylate ethyl acetoacetate aluminum, tris (ethylacetoacetate) aluminum, tris (n-propylacetoacetate) aluminum, tris (isopropylacetoacetate) aluminum, Tris (n-butylacetoacetate) aluminum, isopropoxybisethyl acetoacetate aluminum, tris (acetylacetonato) aluminum, diisopropylate ethylacetonate aluminum, monoethylacetoacetate bis (acetylacetonato) aluminum, diisopropylate mono -Sec-Butoxyaluminum-based aluminum chelate compound, tetrakis (n-propylacetoacete) G) zirconium, there is tetrakis (acetylacetonate) zirconium, tetrakis (acetylacetonato) zirconium, tetrakis (ethylacetoacetate) zirconium chelate compounds such as zirconium.

The amount of the chelate compound is 1 to 6% by weight, particularly 2 to 4% by weight based on the siloxane-modified polyester resin (solid content).
Weight percent is preferred. If it is less than 1% by weight, the crosslink density tends to be insufficient and the solvent resistance and further the low temperature curability tend to be poor. On the other hand, if it exceeds 6% by weight, excessive cross-linking occurs and the gloss decreases,
In addition, the physical properties tend to deteriorate.

Further, the coating composition of the present invention contains a curing catalyst. As the curing catalyst, an organic tin compound, an acidic phosphoric acid ester, or a reaction product thereof with an amine is preferable in terms of moisture resistance, catalytic ability, paint stability and the like. Specifically, organic tin compounds such as dibutyltin laurate, dibutyltin dimaleate, dioctyltin laurate, dioctyltin dilaurate, monomethyl phosphate, monoethyl phosphate, monobutyl phosphate, monooctyl phosphate, dibutyl phosphate, dioctyl. Examples thereof include acid phosphates such as phosphates, hexylamine, di-2-ethylhexylamine, dodecylamine, and the like, and adducts of the aforementioned acid phosphates.

The amount of curing catalyst is 0.001 to 2% by weight, especially 0.01 to 1% by weight, based on the siloxane-modified polyester resin (solid content).
It is preferred that If it is less than 0.001% by weight, the catalytic effect is not sufficient, and if it exceeds 2% by weight, the physical properties are deteriorated due to excessive crosslinking and the coating stability tends to be deteriorated.

The coating composition of the present invention comprises rutile type titanium white, iron oxide,
Disperse inorganic pigments such as alumina oxide, silicon carbide, silica, etc., or metal pieces such as aluminum, stainless steel, etc., carbon, organic pigments such as phthalocyanine blue, etc., and then ester, aromatic, ketone, hydrocarbon, alcohol, etc. A heat resistant coating can be obtained by appropriately selecting from the solvents mentioned above and diluting to an appropriate viscosity.

Further, for the heat resistance of the present invention, a dispersant such as a silicone type or high molecular weight polycarboxylic acid salt, a leveling agent and the like can be appropriately selected and used.

The heat-resistant paint containing the coating composition of the present invention is applied to a base material such as aluminum to a thickness of 20 to 60 μm (dry film thickness),
By baking at 250 ℃ for 20 to 30 minutes, heat-resistant yellowing and a coating with excellent adhesion to the substrate after heat treatment can be obtained.

(Examples) Hereinafter, the present invention will be described in detail with reference to Examples.

Parts and% in each example represent parts by weight and% by weight, respectively.

Example 1 (A) Production of polyester resin In a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a rectification column, and a nitrogen gas introducing device, 109.8 parts of neopentyl glycol and 210.8 parts of trimethylolethane, 173.6 parts of terephthalic acid and 0.06 part of tetrabutyl titanate were charged and heated to 230 ° C in 4 to 6 hours. When the external appearance became transparent, cooled, and 173.6 parts of isophthalic acid was charged at 160 ° C or less and heated in 3 to 4 hours. At the same temperature, the reaction proceeded until the acid value reached 8.6 and cooled,
The solid content was adjusted to 70% by diluting with a solvent of cyclohexanone / xylol = 5/5 (weight ratio).

(B) Production of Methylphenylpolysiloxane Modified Polyester Resin Obtained in Example (A) in a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a dehydration trap tube, and a nitrogen gas introducing device. 420.0 parts polyester resin, silanol group-containing methylphenyl polysiloxane resin TSR-160
(Toshiba Silicone Co., Ltd., solid content 60%) 210.0 parts was charged and the temperature was raised to 145 ° C and kept at the same temperature for 1.5 hours and cooled. 120
Add 0.63 parts of tetrabutyl titanate below ℃, 145 ℃
The temperature was raised to. At the same temperature, the reaction was allowed to proceed until the Gardner viscosity reached W and cooled, and the solid content was adjusted to 60% with dipropylene glycol monomethyl ether.

The Gardner viscosity was measured by diluting 18.0 parts of the flask contents with 2.0 parts of dipropylene glycol monomethyl ether.

(C) Manufacture of paint and test piece In 108.3 parts of the methylphenylpolysiloxane-modified polyester resin obtained in (B), 35 parts of titanium white CR-95 (rutile titanium, manufactured by Ishihara Sangyo Co., Ltd.) was added. 3μ with three rolls
dispersed to m or less. Then, 1.3 parts of acetylacetone zirconium butyrate and 0.13 part of dibutyltin dilaurate were added and mixed. Then dilute to 60% solid content with thinner (propylene glycol methyl ether acetate / xylol / cyclohexanone = 60/30/10, weight ratio),
The paint was adjusted. Apply this paint to an aluminum plate (JIS A 1050,0.8
A bar coater # 60 was applied to t × 70 × 150 (mm), set for 5 minutes, and then baked at 180 ° C. for 30 minutes to prepare a test piece.

Example 2 (A) Production of Methylphenylpolysiloxane-Modified Polyester Resin Example 1 In a one-four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a dehydration trap tube, and a nitrogen gas introducing device.
510.0 parts of the polyester resin obtained in (A), a silanol group-containing methylphenylpolysiloxane resin TSR-160
(Toshiba Silicone) 105.0 parts was charged and the temperature was raised to 145 ° C. and kept at the same temperature for 1.5 hours and cooled. 0.63 parts of tetrabutyl titanate was added below 120 ℃, and the temperature was raised to 145 ℃. At the same temperature, the reaction was allowed to proceed until the Gardner viscosity reached V to W, followed by cooling, and the solid content was adjusted to 60% with dipropylene glycol monomethyl ether. The Gardner viscosity was measured by diluting 17.6 parts of the flask contents with 2.4 parts of dipropylene glycol monomethyl ether.

(B) Production of paint and preparation of test piece 35 parts of titanium white CR-95 (rutile type titanium, manufactured by Ishihara Sangyo Co., Ltd.) was added to 108.3 parts of the methylphenylpolysiloxane-modified polyester resin obtained in (A). 3μ with three rolls
dispersed to m or less. Then 2.0 parts of diisopropylate ethylacetone aluminum, dibutyltin dilaurate
0.13 parts was added and mixed. After that, the paint was adjusted by diluting it with a thinner (propylene glycol methyl ether acetate / xylol / cyclohexanone = 60/30/10, weight ratio) to a solid content of 60%, and adjusting this paint to an aluminum plate (JIS A 1050,0.8).
A bar coater # 60 was applied to t × 70 × 150 (mm), set for 5 minutes, and then baked at 180 ° C. for 30 minutes to prepare a test piece.

Example 3 (A) Production of Polyester Resin A four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a rectification column, and a nitrogen gas introducing device was placed in a four-necked flask having 142.1 parts of neopentyl glycol and 181.0 parts of trimethylolethane. 174.6 parts of terephthalic acid and 0.06 part of tetrabutyl titanate were charged, and the temperature was raised to 230 ° C in 4 to 6 hours, and when it became transparent, it was cooled. At the same temperature, the reaction proceeded until the acid value reached 8.1 and cooled,
Cyclohexanone / xylol = 1/1 (weight ratio) was diluted to adjust the solid content to 70%.

(B) Production of Methylphenylpolysiloxane-Modified Polyester Resin The polyester obtained in Example (A) was placed in a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a dehydration trap tube, and a nitrogen gas introducing device. Resin 420.0 parts, silanol group-containing methylphenyl polysiloxane resin TSR-160
210.0 parts (manufactured by Toshiba Silicone Co., Ltd.) were charged and the temperature was raised to 145 ° C. and kept at the same temperature for 1.5 hours and cooled. 0.63 parts of tetrabutyl titanate was added below 120 ℃, and the temperature was raised to 145 ℃. At the same temperature, the reaction progresses until the Gardner viscosity reaches T to U and cools, and solid content is 60% with dipropylene glycol monomethyl ether.
Adjusted to. The Gardner viscosity is 1
7.7 parts of dipropylene glycol monomethyl ether 2.3
It was diluted with 1 part and measured.

(C) Manufacture of paint and preparation of test piece To 166.6 parts of the methylphenylpolysiloxane-modified polyester resin obtained in (B), 100 parts of titanium white CR-95 (rutile titanium, manufactured by Ishihara Sangyo Co., Ltd.) 3μ with this roll
dispersed to m or less. Then 1.3 parts of diisopropylate ethylacetone aluminum and dibutyltin dilaurate
0.13 parts was added and mixed. Then thinner (propylene glycol methyl ether acetate / xylol /
Cyclohexanone = 60/30/10 weight ratio)) to a solid content of 60% to prepare a paint. Apply this paint to an aluminum plate (JIS A 10
50, 0.8 t × 70 × 150 (mm)) was painted with a bar coater # 60, set for 5 minutes, and then baked at 180 ° C. for 30 minutes.

Example 4 (A) Production of Polyester Resin 159.3 parts of neopentyl glycol and 180.1 parts of trimethylolpropane were placed in a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a rectification column, and a nitrogen gas introducing device. Charge 165.4 parts of terephthalic acid and 0.06 part of tetrabutyl titanate, raise the temperature to 230 ° C in 4 to 6 hours, and cool when it becomes transparent to the outside.
The temperature was raised over a period of time, the reaction was continued at the same temperature until the acid value reached 7.8, and the mixture was cooled and diluted with cyclohexanone / xylol = 5/5 (weight ratio) to adjust the solid content to 70%.

(B) Production of Methylphenylpolysiloxane-Modified Polyester Resin The polyester obtained in Example (A) was placed in a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a dehydration trap tube, and a nitrogen gas introducing device. 420.0 parts of resin and 180.0 parts of silanol group-containing methylphenylpolysiloxane resin KR211 (manufactured by Shin-Etsu Chemical Co., Ltd.) were charged and the temperature was raised to 145 ° C. and kept at the same temperature for 1.5 hours and cooled. 0.63 parts of tetrabutyl titanate was added below 120 ℃, and the temperature was raised to 145 ℃. At the same temperature, the reaction was allowed to proceed until the Gardner viscosity reached W and cooled, and the solid content was adjusted to 60% with dipropylene glycol monomethyl ether.
The Gardner viscosity was measured by diluting 17.1 parts of the flask contents with 2.9 parts of dipropylene glycol monomethyl ether.

(C) Production of paint and preparation of test piece To 108.3 parts of the methylphenylpolysiloxane-modified polyester resin obtained in (B), 35 parts of titanium white CR-95 (rutile type titanium, manufactured by Ishihara Sangyo Co., Ltd.) were mixed. 3 μm with this roll
Dispersed below. Then 1.3 parts of diethylpropionate ethylacetone aluminum and 0.13 of dibutyltin dilaurate
Parts were added and mixed. After that, the paint was adjusted by diluting it with a thinner (propylene glycol methyl ether acetate / xylol / cyclohexanone = 60/30/10 (weight ratio)) to a solid content of 60% and adjusting this paint to an aluminum plate (JIS A 1050,0.8).
A bar coater # 60 was applied to t × 70 × 150 (mm), set for 5 minutes, and then baked at 180 ° C. for 30 minutes to prepare a test piece.

Comparative Example 1 A test piece was prepared by coating and painting in the same manner as in Example 1 (C) except that acetylacetone zirconium butyrate and dibutyltin dilaurate were removed.

Comparative Example 2 A test piece was prepared by coating and coating in the same manner except that the acetylacetone zirconium butyrate of Example 1 (C) was removed.

Comparative Example 3 (A) Production of Polyester Resin In a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a rectification column, and a nitrogen gas introduction device, 250.0 parts of neopentyl glycol and 52.0 parts of trimethylolethane, Charge 193.0 parts of terephthalic acid and 0.06 part of tetrabutyl titanate, raise the temperature to 230 ° C in 4 to 6 hours and cool when it becomes transparent to the outside, and charge 186.0 parts of isophthalic acid below 160 ° C to charge 3 to 4
The temperature was raised over time, the reaction was advanced to an acid value of 7.6 at the same temperature, and the mixture was cooled and diluted with cyclohexanone / xylol = 5/5 (weight ratio) to adjust the solid content to 70%.

(B) Production of Methylphenylpolysiloxane Modified Polyester Resin Obtained in Example (A) in a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a dehydration trap tube, and a nitrogen gas introducing device. 420.0 parts polyester resin, silanol group-containing methylphenyl polysiloxane resin TSR-160
210.0 parts (manufactured by Toshiba Silicone Co., Ltd.) were charged and the temperature was raised to 145 ° C. and kept at the same temperature for 1.5 hours and cooled. 0.63 parts of tetrabutyl titanate was added below 120 ℃, and the temperature was raised to 145 ℃.
At the same temperature, the reaction proceeded until the Gardner viscosity reached T and cooled, and the solid content was adjusted to 60% with dipropylene glycol monomethyl ether. The Gardner viscosity is 1 for the contents of the flask.
8.0 parts of dipropylene glycol monomethyl ether 2.0
It was diluted with 1 part and measured.

(C) Production of paint and preparation of test piece To 108.3 parts of the methylphenylpolysiloxane-modified polyester resin obtained in (B), 35 parts of titanium white CR-95 (rutile type titanium, manufactured by Ishihara Sangyo Co., Ltd.) were mixed. 3 μm with this roll
Dispersed below. Next, 1.3 parts of diisopropylate ethylacetone aluminum and 0.1 part of dibutyltin dilaurate
3 parts were added and mixed. After that, the paint was adjusted by diluting it to a solid content of 60% with thinner (propylene glycol methyl ether acetate / xylol / cyclohexanone = 60/30/10), and this paint was coated on an aluminum plate (JIS A 1050, 0.8t × 70 × 1).
50 (mm) was coated with a bar coater # 60, set for 5 minutes and then baked at 180 ° C for 30 minutes to prepare a test piece.

 Table 1 shows the composition and coating film characteristics of Examples and Comparative Examples.

(Note) 1) Measurement method of number average molecular weight 150 mg of a sample is weighed and dissolved in 5 ml of tetrahydrofuran (Wako Pure Chemical Industries, reagent grade 1), and then high performance liquid chromatography (Hitachi, Model 655A-11, column is Hitachi) Measured with Kasei Co., Ltd., using Gelpack R440, R450, R400M). The molecular weight was measured with the above equipment using standard polystyrene, and a calibration curve was prepared and converted.

2) 60 ° specular gloss was measured with a Suga Test Instruments gloss meter.

3) The scratch hardness was measured with Mitsubishi Uni, manufactured by Mitsubishi Pencil Co., Ltd.

4) Gauze was impregnated with methyl ethyl ketone and rubbed 50 times, and then the glossiness was visually evaluated according to the following criteria.

○ No abnormality △ Slightly glossy × melted 5) Leave the coating film in an air atmosphere at 250 ° C for 15 hours, then at 180 ° C
ΔE was measured with a color difference meter manufactured by Nippon Denshoku Co., Ltd. using a coating plate baked at × 30 as a standard.

6) After leaving the coating film in an air atmosphere at 250 ° C for 15 hours, 1 × 1 mm
The 100 squares were cut with a cutter and peeled off with cellophane tape, showing the peeled squares.

7) Weight% based on siloxane-modified polyester resin.

(Effects of the Invention) The heat-resistant paint contained in the coating composition according to the present invention is excellent in heat-resistant yellowing of the coating film, adhesion to the substrate after heat treatment, low-temperature curing property, and excellent economical efficiency. ing.

Therefore, the coating composition according to the present invention is most suitable as a heat resistant coating for heating appliances, household electric appliances and the like.

Claims (5)

[Claims] 1. An alcohol component containing an aliphatic polyhydric alcohol having a neopentyl structure as a main component, which has 2-3 hydroxyl groups in one molecule, and an acid component containing an aromatic dibasic acid as a main component. A condensate obtained by reacting, a siloxane-modified polyester obtained by reacting a polyester resin having a number average molecular weight of 1,000 to 4,000 and a hydroxyl value of 250 to 400 with a silanol group-containing methylphenyl polysiloxane resin. A coating composition comprising a resin, a metal chelate compound and a curing catalyst. 2. The siloxane-modified polyester resin comprises a polyester resin and a silanol group-containing methylphenylpolysiloxane resin in a former / latter solid content weight ratio of 90/10.
The coating composition according to claim 1, which is obtained by reacting at a ratio of 60/40. 3. The coating composition according to claim 1, wherein the metal chelate compound is an aluminum-based, titanium-based or zirconium-based chelate compound, and the chelate compound is contained in an amount of 1 to 6% by weight based on the siloxane-modified polyester resin. Stuff. 4. A curing catalyst is an organic tin compound, an acidic phosphoric acid ester, or a reaction product thereof with an amine, and the curing catalyst is 0.001 to 2 with respect to a siloxane-modified polyester resin.
The coating composition according to claim 1, 2 or 3, wherein the coating composition comprises wt%. 5. A heat resistant paint comprising the paint composition according to claim 1, 2, 3 or 4.