JP5500383B2 - Composition comprising carboxyl group-containing modified polyester resin, and coating composition - Google Patents

Description

  The present invention relates to a composition comprising a carboxyl group-containing modified polyester resin, and a coating composition using the composition.

  Polyester resins are better used in applications such as coating agents and paints because they have better processability than acrylic resins and epoxy resins. Further, as a means of improving the hardness and solvent resistance, which were the disadvantages of the polyester resin, while maintaining such features of the polyester resin, a polyester resin composition in which a partial condensate of polyalkoxysilanes is dispersed in the polyester resin. There is known a method of curing sol-gel.

  Further, for example, Patent Document 1 discloses that a reactive silicone oil is added to a polyester resin obtained by subjecting a dicarboxylic acid containing 40 to 100 mol% of an aromatic dicarboxylic acid, a diol, and a polybasic acid to a heat reaction. A modified polyester resin composition having a number average molecular weight of 5000 or more obtained by heating reaction of 1 to 5% by weight is described. According to this, not only processability but also scratch resistance and stain resistance are described. It is said that a coating film excellent in chemical resistance and the like can be obtained.

Japanese Patent Laid-Open No. 2-58532

  The main object of the present invention is to provide a novel modified polyester resin composition suitable for coating agents and paints that can provide a coating film excellent in various performances such as processability, solvent resistance, and hardness. .

  As a result of intensive studies, the present inventor has found that the above problem can be solved by a modified polyester resin composition having the following constitution.

  That is, the present invention comprises a condensation reaction of dicarboxylic acids (a1), diols (a2), triols (a3), and tricarboxylic acids (a4) containing 60 to 100 mol% of an aromatic dicarboxylic acid, and For the polymer (A) having a number average molecular weight of 5000 to 20000 having a carboxyl group and a hydroxyl group in the molecule (in terms of solid content), the following general formula (I) (wherein n is 2 to 100) A composition comprising a carboxyl group-containing modified polyester resin obtained by reacting 10 to 20 parts by weight of a polymethoxysilane partial condensate (B) represented by an integer); the modified polyester resin composition The present invention relates to a coating composition comprising a product (1) and an aziridine-based curing agent (2) having at least three aziridylyl groups.

  The composition (1) of the present invention is characterized in that the carboxyl group-containing polymer (A) as a base has a crosslinked structure and / or a branched structure, and that the carboxyl group-containing polymer (A) has a predetermined amount of poly The modified polyester resin obtained by reacting the methoxysilane partial condensate (B) is characterized by having a carboxyl group as a reaction site at the molecular end. Therefore, various curing agents can be applied to the composition (1), and coating compositions excellent in various coating film performances can be obtained.

  In addition, since the coating composition of the present invention includes the composition (1) and an aziridine-based curing agent (2) having at least three aziridylyl groups, not only processability, solvent resistance, and hardness but also transparency The coating film can be obtained with various performances such as properties, adhesion to a substrate (particularly an aluminum substrate), boiling water resistance, and blocking resistance. Therefore, the coating composition is particularly suitable for coating on metal or plastic materials.

  The composition (1) of the present invention comprises dicarboxylic acids (a1) (hereinafter referred to as (a1) component) and diols (a2) (hereinafter referred to as (a2) component) containing 60 to 100 mol% of aromatic dicarboxylic acid. , Triols (a3) (hereinafter referred to as component (a3)) and tricarboxylic acids (a4) (hereinafter referred to as component (a4)) undergo a condensation reaction, and have a number average molecular weight of 5,000 to 20,000. The following general formula (I) (wherein n is an integer of 2 to 100) with respect to 100 parts by weight (in terms of solid content) of polymer (A) (hereinafter referred to as component (A)) having a carboxyl group and a hydroxyl group in the molecule And a carboxyl group-containing modified polyester resin obtained by reacting 10 to 20 parts by weight of a polymethoxysilane partial condensate (B) (hereinafter referred to as component (B)). Than is.

  As the aromatic dicarboxylic acid contained in the component (a1), various known ones can be used without particular limitation. Specific examples include acid anhydrides for isophthalic acid, terephthalic acid, phthalic acid, diphenylmethane-4,4′-dicarboxylic acid, and 2,6-naphthalenedicarboxylic acid, and the corresponding ones, One kind can be used alone, or two or more kinds can be used in combination.

  The component (a1) can contain various known dicarboxylic acids other than the aromatic dicarboxylic acid. Specifically, for example, aliphatic dicarboxylic acids [oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, pimelic acid, suberic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid Etc.], alicyclic dicarboxylic acids [hexahydrophthalic acid, hexahydrophthalic anhydride, 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, etc.] and the like. , Or a combination of two or more.

  The content of the aromatic dicarboxylic acid in the component (a1) is about 60 to 100 mol%, preferably 80 to 100 mol%, particularly from the viewpoint of the hardness of the coating film.

  As the component (a2), various known compounds can be used without particular limitation. Specifically, for example, branched aliphatic diol [neopentyl glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,3-propanediol, 1,2-propanediol, etc.], linear Aliphatic diol [ethylene glycol, diethylene glycol, triethylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, pentanediol, 1,6-hexanediol, etc.], alicyclic Diol [1,4-cyclohexanedimethanol, diol obtained by hydrogenating dimer acid, ethylene oxide adduct of hydrogenated bisphenol A, etc.], aromatic diol [catechol, resorcinol, hydroquinone, xylylene glycol, bishydroxyethoxybenzene, etc. These are one type. It can be used alone or in combination of two or more.

  The component (a3) is an essential component for introducing a crosslinked structure and / or a branched structure into the component (A), and by using this, the hydroxyl value and the number average molecular weight of the component (A) are predetermined. Range. Such a crosslinked structure and / or branched structure contributes to the performance of the coating film such as hardness and solvent resistance. Specific examples of the component (a3) include aliphatic triols [glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, etc.], fat Examples thereof include cyclic triols [cyclohexanetriol and the like] and aromatic triols [pyrogallol, phloroglucinol and the like], and these can be used alone or in combination of two or more.

  Various known tetrafunctional or higher functional polyols can be used in combination with the component (a3). Specific examples include tetraols such as erythritol, sorbitol, pentaerythritol, and diglycerin, and dipentaerythritol, and these can be used alone or in combination of two or more.

  The component (a4) is essential for introducing a cross-linked structure and / or a branched structure into the component (A) and having a carboxyl group at the molecular end. Such a crosslinked structure and / or branched structure contributes to the performance of the coating film such as hardness and solvent resistance. When the component (a4) is not used, the reaction system tends to gel during the heating reaction of the component (A) and the component (B). Specific examples of the component (a4) include trimellitic anhydride, butane-1,2,4-tricarboxylic acid, naphthalene-1,2,4-tricarboxylic acid, and the like. Can be used alone or in combination of two or more.

  Various known tetracarboxylic acids can be used in combination with the component (a4). Specifically, for example, diphenyl ether-3,3 ′, 4,4′-tetracarboxylic acid, butane-1,2,3,4-tetracarboxylic acid, benzene-1,2,4,5-tetracarboxylic acid , Biphenyl-3,3 ′, 4,4′-tetracarboxylic acid, naphthalene-1,2,4,5-tetracarboxylic acid, acid anhydrides thereof, and the like. Two or more kinds can be used in combination.

  The amount of component (a1) to component (a4) used is not particularly limited, but usually the amount of component (a1) used: The total amount of component (a2) and component (a3) is 40 to 45 mol%: It is the range which becomes about 55-60 mol%. Moreover, the usage-amount of (a3) component is about 1-10 mol% normally when the total amount of (a2) component and (a3) component is 100 mol%, Preferably it is 3-7 mol%. The amount of component (a4) used is usually about 2.0 to 8.0 mol%, preferably 2.5 to about 100 mol% when the total amount of component (a1) and component (a4) is 100 mol%. 6.5 mol%.

  The manufacturing method of (A) component is not specifically limited, Various well-known methods are employable. Specifically, for example, a method of reacting the components (a1) to (a4) in a lump or a sequential reaction method may be mentioned. Examples of the latter include a method in which the components (a1) to (a3) are subjected to (dehydration) condensation reaction, and then the (a4) component is further subjected to (dehydration) condensation reaction.

  (A) Although reaction conditions in the case of manufacture of a component are not specifically limited, Usually, reaction temperature is about 150-250 degreeC, and reaction time is about 5 to 10 hours. The reaction can be performed under normal pressure or reduced pressure. Moreover, you may perform reaction in presence of the below-mentioned organic solvent (C).

  In the production of the component (A), various known catalysts can be used. Specifically, for example, germanium dioxide, germanium tetraethoxide, germanium tetra n-butoxide, antimony trioxide, dibutyltin oxide, zinc acetate (dihydrate), monobutyltin oxide, dibutyltin oxide, titanium tetrabutoxide, etc. These may be used alone or in combination of two or more.

  The component (A) thus obtained has a number average molecular weight (referred to polystyrene conversion value by gel permeation chromatography (GPC) measurement, hereinafter the same) of 5000 to 20000, preferably 8000 to 15000. If the number average molecular weight is less than 5,000, the processability of the coating film may be insufficient, and if it exceeds 20,000, the coating film may be whitened.

  Although the other physical property of (A) component is not specifically limited, For example, a hydroxyl value (JIS-K-0070) is about 5-20 mgKOH / g normally, Preferably it is 8-15 mgKOH / g. By setting the hydroxyl value to 5 or more, the reaction between the component (A) and the component (B) (demethanol reaction) proceeds sufficiently, and the coating film using the composition (1) of the present invention is sufficiently transparent. Sex is obtained. On the other hand, by setting the hydroxyl value to 20 or less, gelation of the reaction system can be suppressed.

  Although the other physical property of (A) component is not specifically limited, For example, when the reactivity of the composition (1) of this invention and the below-mentioned hardening | curing agent is considered, an acid value (mgKOH / g) is about 15-50 normally. , Preferably 20-40. Further, from the viewpoint of coating film hardness, the glass transition temperature (JIS-K7121) of the component (A) is usually about 10 to 50 ° C, preferably 15 to 40 ° C.

  As the component (B), a polymethoxysilane partial condensate represented by the following general formula (I) (wherein n represents an integer of 2 to 100, preferably 4 to 20) is used.

  The amount of component (B) used relative to component (A) is usually about 10 to 20 parts by weight (in terms of solid content), preferably 12 to 18 parts by weight, based on 100 parts by weight of component (A). It is the range which becomes (solid content conversion). When it is less than 10 parts by weight, the hardness of the coating film and the adhesion to the substrate are insufficient. Moreover, when it exceeds 20 weight part, the transparency of a coating film will run short.

  The method of reacting (B) component with (A) component (heating reaction) is not particularly limited. Usually, however, (A) component and (B) component are charged in a suitable reaction vessel, and usually about 90 to 110 ° C. A method of heating for about 5 to 10 hours is usually used while the methanol produced by the reaction between the hydroxyl group and the alkoxy group is distilled out of the system by an appropriate means. It should be noted that the transparency and hardness of the coating are impaired particularly by simply mixing the (A) component and the (B) component, and other performance becomes insufficient.

  The composition (1) thus obtained contains, as a main component, a modified polyester resin having a carboxyl group at the molecular end (a reaction product of the components (A) and (B)). The amount of the carboxyl group of the modified polyester resin is not particularly limited. Usually, however, the acid value (JIS-K-0070) of the composition (1) is usually about 15 to 50 mgKOH / g, preferably 20 to 40. It is. The number average molecular weight of the composition (1) is usually about 6000 to 30,000.

  The composition (1) can further contain various known organic solvents (C) (hereinafter referred to as component (C)). Specifically, for example, aromatic hydrocarbon-based organic solvents [Solvesso # 100, Solvesso # 150 (both manufactured by Exxon Chemical Co., Ltd.), toluene, xylene, etc.], ester-based organic solvents [methyl acetate, ethyl acetate, Isopropyl acetate, butyl acetate, amyl acetate, ethyl formate, butyl propionate, methyl cellosolve acetate, cellosolve acetate, etc.), ketone organic solvents (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), ether organic solvents (dioxane, diethyl ether) , Tetrahydrofuran, etc.], aprotic polar organic solvents [N-methylpyrrolidone, dimethylformamide, dimethylacetamide, etc.], alcohol solvents [methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, etc.] Is, it can be used alone or in combination of two or more, of them. Among these, among the ester organic solvents, ketone organic solvents, ether organic solvents and alcohol solvents, particularly those having a boiling point of about 60 to 130 ° C., the coating composition of the present invention is made into a plastic group. A coating film can be obtained in a short time when applied to a material.

  The composition (1) includes various known sol-gel curing catalysts (D) (hereinafter referred to as “the sol-gel curing reaction (demethanol reaction)”) for the alkoxy group derived from the component (B). , (D) component). Specific examples of the component (D) include tertiary amines [1,8-diaza-bicyclo [5.4.0] undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylamino. Ethanol, tris (dimethylaminomethyl) phenol, etc.], imidazoles [2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, etc.], organic phosphines [tributylphosphine, methyl Diphenylphosphine, triphenylphosphine, diphenylphosphine, phenylphosphine, etc.], tetraphenylboron salts [tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, N-methyl Morpholine tetraphenyl borate, etc.], water and the like, it may be used alone or in combination of two or more, of them.

  The content of the component (C) and the component (D) in the composition (1) is usually about 40 to 60% by weight and about 0.05 to 0.2% by weight, respectively.

  The coating composition of the present invention comprises a composition (1) and an aziridine-based curing agent (2) having at least three aziridylyl groups (hereinafter simply referred to as a curing agent (2)).

  Specific examples of the curing agent (2) include, for example, trifunctional aziridine compounds [tetramethylolmethane-tri- (β-aziridinylpropionate), trimethylolpropanetris (β-aziridinylpropionate). ), Glyceryl tris (β-aziridinyl propionate), etc.], tetrafunctional aziridine compounds [tetraaziridinyl metaxylenediamine, tetraaziridinylmethylparaxylenediamine, tetramethylpropanetetraaziridinylpropionate These may be used alone or in combination of two or more.

  The coating composition of the present invention can contain various volatile amines and ammonia for the purpose of storage stability. Examples of volatile amines include monomethylamine, dimethylamine, trimethylamine, triethylamine, monoethylamine, diethylamine, monobutylamine, cyclohexylamine, aniline, arylamine, alkanolamine, and the like. Alternatively, two or more kinds can be used in combination. Among these, triethylamine is particularly preferable from the viewpoints of storage stability of the coating composition and water resistance of the coating film.

  Although the usage-amount of a composition (1) and a hardening | curing agent (2) in the coating composition of this invention is not specifically limited, Usually, when a composition (1) is 100 weight part (solid content conversion), The curing agent (2) is usually about 6 to 20 parts by weight.

  In addition, the coating composition of the present invention includes the component (C), filler, mold release agent, surface treatment agent, flame retardant, viscosity modifier, plasticizer, antibacterial agent, antifungal agent, leveling agent, Antifoaming agents, colorants, stabilizers, and the like can also be applied.

  The substrate to which the coating composition of the present invention is applied is not particularly limited. For example, plastic [polycarbonate, polymethyl methacrylate, polystyrene, polyester, polyolefin, nylon, epoxy resin, melamine resin, triacetyl cellulose resin, ABS resin, AS Resin, norbornene resin, etc.], film made of the plastic (surface treatment such as corona discharge treatment, aluminum deposition, etc.), metal (iron, chin-free steel, copper, aluminum, etc.), glass material [glass Plate, glass cloth, etc.). Among these, aluminum base materials (aluminum metal, aluminum vapor-deposited plastic film) are preferable from the viewpoint of adhesion and the like.

The method for applying the coating composition of the present invention to a substrate is not particularly limited, and may be by various known means. Specific examples include a roll coater, a reverse roll coater, a gravure coater, a knife coater, and a bar coater. Moreover, the coating amount to a base material is not specifically limited, Usually, it is about 0.01-10 g / m < ² > as dry solid content.

  Hereinafter, the present invention will be further described with reference to production examples, examples and comparative examples, but the present invention is not limited to these examples.

  The “number average molecular weight” is a polystyrene equivalent value obtained using a commercially available measuring instrument (product name “HLC-8220GPC”, manufactured by Tosoh Corporation, developing solvent: tetrahydrofuran). The glass transition temperature is a value obtained with a commercially available measuring instrument (product name “DSC6200”, manufactured by Seiko Instruments Inc.).

<Preparation of polymer (A), etc.>
Production Example 1
In a flask equipped with a stirrer, a thermometer and a nitrogen gas inlet tube, and a reflux dehydrator, 478.5 parts of terephthalic acid, 402.1 parts of isophthalic acid, 87.6 parts of azelaic acid, 255.7 parts of ethylene glycol, 1, 353.9 parts of 6-hexanediol and 23 parts of glycerin were charged, and the reaction system was heated with stirring to melt them. Next, 0.16 part of antimony trioxide was added, a vacuum decompression apparatus was connected to the reaction vessel, and a reduced pressure polycondensation reaction was performed at 235 ° C. and 2.8 kPa for 1 hour. Subsequently, the reduced pressure state was released, the reaction system was cooled to 150 ° C., 52.5 parts of trimellitic anhydride was charged into the reaction system, and the temperature was kept for 1 hour. Next, 470.4 parts of methyl isobutyl ketone (MIBK) was added to the system, the nonvolatile content was 67%, the number average molecular weight was 10,000, the hydroxyl value was 8.6, the acid value was 33.2, and the glass transition temperature was 19 A solution of polymer (A-1) at 0 ° C. was obtained.

Production Example 2
In a flask similar to Production Example 1, 478.5 parts of terephthalic acid, 402.1 parts of isophthalic acid, 87.6 parts of azelaic acid, 255.7 parts of ethylene glycol, 353.9 parts of 1,6-hexanediol, and glycerin 23 parts were charged and the reaction system was heated with stirring to melt them. Next, 0.16 part of antimony trioxide was added, a vacuum decompression apparatus was connected to the reaction vessel, and a reduced pressure polycondensation reaction was performed at 235 ° C. and 2.8 kPa for 40 minutes. Subsequently, the reduced pressure state was released, the reaction system was cooled to 150 ° C., 52.5 parts of trimellitic anhydride was charged into the reaction system, and the temperature was kept for 1 hour. Next, 470.4 parts of methyl isobutyl ketone (MIBK) was added to the system, the non-volatile content was 67%, the number average molecular weight was 6500, the hydroxyl value was 8.6, the acid value was 33.9, and the glass transition temperature was 17 A solution of polymer (A-3) at 0 ° C. was obtained.

Production Example 3
In a flask similar to Production Example 1, 478.5 parts of terephthalic acid, 402.1 parts of isophthalic acid, 87.6 parts of azelaic acid, 255.7 parts of ethylene glycol, 353.9 parts of 1,6-hexanediol, and glycerin 23 parts were charged and the reaction system was heated with stirring to melt them. Subsequently, 0.16 part of antimony trioxide was added, a vacuum decompression apparatus was connected to the reaction vessel, and a reduced pressure polycondensation reaction was performed at 235 ° C. and 0.7 kPa for 1 hour. Subsequently, the reduced pressure state was released, the reaction system was cooled to 150 ° C., 52.5 parts of trimellitic anhydride was charged into the reaction system, and the temperature was kept for 1 hour. Next, 470.4 parts of methyl isobutyl ketone (MIBK) was added to the system, the non-volatile content was 67%, the number average molecular weight was 17000, the hydroxyl value was 8.6, the acid value was 35.7, and the glass transition temperature was 20 A solution of polymer (A-4) at 0 ° C. was obtained.

Comparative production example 1
In a flask similar to Production Example 1, 478.5 parts of terephthalic acid, 402.1 parts of isophthalic acid, 87.6 parts of azelaic acid, 255.7 parts of ethylene glycol, 353.9 parts of 1,6-hexanediol, and glycerin 23 parts were charged and the reaction system was heated with stirring to melt them. Next, 0.16 part of antimony trioxide was added, a vacuum decompression apparatus was connected to the reaction vessel, and a reduced pressure polycondensation reaction was performed at 235 ° C. and 5.6 kPa for 1 hour. Subsequently, the reduced pressure state was released, the reaction system was cooled to 150 ° C., 52.5 parts of trimellitic anhydride was charged into the reaction system, and the temperature was kept for 1 hour. Next, 470.4 parts of MIBK was added to the system, and a polymer having a nonvolatile content of 67%, a number average molecular weight of 2000, a hydroxyl value of 23.4, an acid value of 33.9, and a glass transition temperature of 17 ° C. Solution was obtained.

Comparative production example 2
In a flask similar to Production Example 1, 478.5 parts of terephthalic acid, 402.1 parts of isophthalic acid, 87.6 parts of azelaic acid, 255.7 parts of ethylene glycol, 353.9 parts of 1,6-hexanediol, and glycerin 23 parts were charged and the reaction system was heated with stirring to melt them. Next, 0.16 part of antimony trioxide was added, a vacuum decompression apparatus was connected to the reaction vessel, and a reduced pressure polycondensation reaction was performed at 235 ° C. and 2.8 kPa for 30 minutes. Subsequently, the reduced pressure state was released, the reaction system was cooled to 150 ° C., 52.5 parts of trimellitic anhydride was charged into the reaction system, and the temperature was kept for 1 hour. Next, 470.4 parts of methyl isobutyl ketone (MIBK) was added to the system, the non-volatile content was 67%, the number average molecular weight was 4000, the hydroxyl value was 16.6, the acid value was 33.2, and the glass transition temperature was 17 A solution of polymer (b) at 0 ° C. was obtained.

Comparative production example 3
In a flask similar to Production Example 1, 366.3 parts of isophthalic acid, 668.7 parts of sebacic acid, 244.6 parts of ethylene glycol, and 298.4 parts of neopentyl glycol were charged, and the reaction system was heated with stirring. These were melted. Next, 0.16 part of antimony trioxide was added, a vacuum decompression apparatus was connected to the reaction vessel, and a reduced pressure polycondensation reaction was performed at 235 ° C. and 2.8 kPa for 1 hour. Subsequently, the reduced pressure state was released, the reaction system was cooled to 150 ° C., 52.5 parts of trimellitic anhydride was charged into the reaction system, and the temperature was kept for 1 hour. Next, 470.4 parts of MIBK was added to the system, and a polymer having a nonvolatile content of 67%, a number average molecular weight of 10,000, a hydroxyl value of 8.6, an acid value of 33.2, and a glass transition temperature of −20 ° C. ) Was obtained.

Comparative production example 4
In a flask similar to Production Example 1, 478.5 parts of terephthalic acid, 402.1 parts of isophthalic acid, 87.6 parts of azelaic acid, 255.7 parts of ethylene glycol, 353.9 parts of 1,6-hexanediol, and glycerin 23 parts were charged and the reaction system was heated with stirring to melt them. Subsequently, 0.16 part of antimony trioxide was added, a vacuum decompression apparatus was connected to the reaction vessel, and a reduced pressure polycondensation reaction was performed at 235 ° C. and 0.7 kPa for 2 hours. Subsequently, the reduced pressure state was released, the reaction system was cooled to 150 ° C., 52.5 parts of trimellitic anhydride was charged into the reaction system, and the temperature was kept for 1 hour. Next, 470.4 parts of methyl isobutyl ketone (MIBK) was added to the system, the non-volatile content was 67%, the number average molecular weight was 22000, the hydroxyl value was 3.6, the acid value was 33.2, and the glass transition temperature was 20 A solution of polymer (d) at 0 ° C. was obtained.

<Preparation of composition (1), etc.>
Example 1
In a flask similar to Production Example 1, 600 parts of the polymer (A-1) solution, tetramethoxysilane partial condensate (manufactured by Tama Chemical Co., Ltd., trade name “methyl silicate 51”, average number of Si 4) 49 Part, MIBK 64.4 parts, and 1 part dibutyltin laurate were added, and methanol removal reaction was carried out at 90-100 ° C. with stirring under a nitrogen stream. During the reaction, methanol was distilled off from the reaction system using a water separator, and when the amount reached about 4 parts, the reaction system was cooled. The time required from the temperature rise to the start of cooling was 6 hours. Next, after the reaction system was cooled to 50 ° C., methanol remaining in the system was removed at 13 kPa for about 15 minutes by connecting a vacuum line. During this time, about 2 parts of methanol were removed. Subsequently, 402 parts of methyl ethyl ketone (MEK) was added, the flask was cooled to room temperature, and a composition (1-1) having a nonvolatile content of 40% and a silica (SiO ₂ ) content of 5.8 wt% was obtained. The value of 5.8% by weight is a calculated value.

Example 2-4, Comparative Example 1-8
According to the composition shown in Tables 2 and 3, according to Example 1, compositions (1-2) to ( 1-4 ) and comparative compositions (e) to ( o ) were obtained. Comparative Examples 4 and 7 are mixed solutions obtained by simply mixing the components having the compositions shown in Table 3 without causing them to react.

Example 5
(Preparation of coating composition)
To 67.3 parts of the composition (1-1), 1.5 parts of triethylamine (TEA) was added and neutralized to obtain a resin solution. Next, 7.7 parts of trimethylolpropane-tris- (β-aziridinylpropionate) (trade name “TAZM” manufactured by Mutual Yakuhin Co., Ltd.) was added to the solution, and methyl ethyl ketone 23.5 was further added. The coating composition was obtained by diluting with parts.

Examples 6 to 8 and Comparative Examples 9 to 16
A coating composition was prepared according to Example 5 with the combinations shown in Table 2.

<Transparency>
The coating composition of Example 5 was applied to a polyethylene terephthalate (PET) film (product name “Lumirror T60”, manufactured by Toray Industries, Inc., 75 μm thick, untreated on both sides) using a bar coater # 2. The obtained PET film was dried (120 ° C., 1 minute) in a smooth air dryer to obtain a PET film having a cured coating film. Subsequently, the haze value of the obtained PET film was measured using a color haze meter (product name “Haze Meter HM150”, manufactured by Murakami Color Research Laboratory Co., Ltd.) and evaluated according to the following criteria. (In the evaluation, correction was performed based on the haze value of the polyethylene terephthalate (PET) film itself as a base). Moreover, the coating composition which concerns on another Example and a comparative example formed the coating film similarly, and evaluated it. The results are shown in Tables 4 and 5.
○: Less than 1.5% △: 1.5% or more and less than 3.0% ×: 3.0% or more

<Processability>
The coating composition of Example 5 was applied to an aluminum plate (product name “A1050P”, manufactured by Nippon Test Panel Co., Ltd., thickness 0.8 mm) using a bar coater # 6, and the resulting aluminum plate Was dried (120 ° C., 1 minute) in a smooth air dryer to obtain an aluminum plate having a cured coating film. Next, the aluminum plate obtained was subjected to a 7 mm overhanging test using an Erichsen testing machine. The degree of cracking and peeling of the processed part was observed with a 50 × magnifier. Moreover, the coating composition which concerns on another Example and a comparative example formed the coating film similarly, and evaluated it. The results are shown in Tables 4 and 5.
○… No cracking / peeling on the coating film △… Slight cracking on the coating film ×… Major cracking / peeling on the coating film

<Coating hardness>
The coating composition of Example 5 was applied to a glass plate using a bar coater # 2, and the resulting glass plate was dried (120 ° C., 1 minute) in a forward air dryer to obtain a cured coating. A glass plate provided with a membrane was obtained. In addition, all the cured coating films were in a state where they did not feel stickiness due to finger touch (tack free). Subsequently, the obtained glass plate was subjected to a hardness (scratch property) test using a Mitsubishi pencil “Uni” according to JIS-K-5600-5-4. Moreover, the coating composition which concerns on another Example and a comparative example formed the coating film similarly, and evaluated it. The results are shown in Tables 4 and 5.

<Adhesion>
The coating composition of Example 5 was applied to Lumirror T60 using a bar coater # 2, and the obtained PET film was dried (120 ° C., 1 minute) in a smooth air dryer to be cured. A PET film provided with a coating film was obtained. Next, for the obtained PET film, according to JIS K5600-5-6, 100 mm of 1 mm square was created on each coating film, adhesive tape was applied, and this was peeled off rapidly in the vertical direction Based on the following criteria, the adhesion of the coating film was evaluated based on the remaining amount of the coating film. Moreover, the coating composition which concerns on another Example and a comparative example formed the coating film similarly, and evaluated it. The results are shown in Tables 4 and 5.
○: 80% or more of the coating film remained Δ: 20% or more and less than 80% of the coating film remained ×: Only less than 20% of the coating film remained

<Solvent resistance>
The coating composition of Example 5 was applied to Lumirror T60 using a bar coater # 2, and the obtained PET film was dried (120 ° C., 1 minute) in a smooth air dryer to be cured. A PET film provided with a coating film was obtained. Next, the obtained PET film was rubbed with a gauze containing methyl ethyl ketone, and the solvent resistance was evaluated according to the following criteria based on the number of times until the film substrate was exposed (one round trip). . Moreover, the coating composition which concerns on another Example and a comparative example formed the coating film similarly, and evaluated it. The results are shown in Tables 4 and 5.
○: 40 times or more
Δ: 10 times or more and less than 40 times
X: Less than 10 times

<Boiling water resistance>
The coating composition of Example 5 was applied to Lumirror T60 using a bar coater # 2, and the obtained PET film was dried (120 ° C., 1 minute) in a smooth air dryer to be cured. A PET film provided with a coating film was obtained. Subsequently, the obtained PET film was boiled in boiling water for 60 minutes, and the state of the coating film was visually evaluated according to the following criteria. Moreover, the coating composition which concerns on another Example and a comparative example formed the coating film similarly, and evaluated it. The results are shown in Tables 4 and 5.
○: No whitening of the coating film and no blistering occurred Δ: The coating film was slightly whitened and slight blistering occurred ×: The coating film was strongly whitened and , Blister has occurred remarkably

<Blocking resistance>
By applying the coating composition of Example 5 to Lumirror T60 "using a bar coater # 2, and drying the obtained PET film in a smooth air dryer (120 ° C, 1 minute), A PET film provided with a cured coating film was obtained. Next, each PET film was covered with an uncoated PET film, applied with a load of ² kg / cm ² , and left in an atmosphere of 60 ° C. and 65% RH for 24 hours. Thereafter, blocking (attachment) when the films were peeled apart was evaluated according to the following criteria. Moreover, the coating composition which concerns on another Example and a comparative example formed the coating film similarly, and evaluated it. The results are shown in Tables 4 and 5.
○: No blocking △: There is blocking on a part of the coating film surface ×: There is significant blocking over the entire coating film surface

<Vapor deposition (aluminum adhesion)>
The coating composition of Example 5 was applied to Lumirror T60 using a bar coater # 2, and the obtained PET film was dried (120 ° C., 1 minute) in a smooth air dryer to be cured. A PET film provided with a coating film was obtained. Next, after vacuum-depositing aluminum on the obtained PET film, according to JIS K5600-5-6, 100 mm of 1 mm squares were formed on each coating film, and adhesive tape was affixed. The adhesiveness was evaluated based on the following criteria based on the remaining amount of the deposited aluminum film when it was peeled rapidly in the direction. The results are shown in Tables 4 and 5.
○: 80% or more of the aluminum deposited film remained Δ: 20% or more and less than 80% of the aluminum deposited film remained ×: Less than 20% of the aluminum deposited film remained

Claims (4)

Dicarboxylic acids (a1), diols (a2), triols (a3), and tricarboxylic acids (a4) containing 60 to 100 mol% of aromatic dicarboxylic acid are subjected to a condensation reaction, and the number average molecular weight is 5,000 to 5,000. It is represented by the following general formula (I) (wherein n represents an integer of 2 to 100) with respect to 100 parts by weight (in terms of solid content) of the polymer (A) having a carboxyl group and a hydroxyl group in the molecule, which is 20000. A composition (1) containing a carboxyl group-containing modified polyester resin obtained by reacting 10 to 20 parts by weight of the polymethoxysilane partial condensate (B).
The composition (1) according to claim 1, wherein the component (A) has a hydroxyl value of 5 to 20 mgKOH / g. The composition (1) according to claim 1 or 2, further comprising an organic solvent (C). The coating composition containing the composition (1) in any one of Claims 1-3, and the aziridine type hardening | curing agent (2) which has at least 3 aziridylyl group.