KR100398442B1 - Polyester based coating composition for anti-stain PCM outside panel - Google Patents

Abstract

The present invention relates to a polyester coating composition for non-pollution PCM exterior materials, and more particularly, to a hydroxy unsaturated polyester resin and a melamine curing agent, including secondary amine shielding or epoxy resin shielding sulfonic acid; Tertiary amine masked sulfonic acids; Isocyanate compounds masked with malonates; Tin curing catalysts; Polyalkylsilicates; In addition, since the alkoxy compound is contained in a certain content ratio, the surface density, fouling resistance, acid resistance and self-cleaning ability of the coating film are excellently improved, and the compatibility of the hydroxy unsaturated polyester resin and polyalkyl silicate is also improved. The present invention relates to a polyester coating composition for non-pollution PCM exterior material which obtains another effect of improving coating appearance properties and workability without additional defoaming agent and leveling agent.

Description

Polyester based coating composition for anti-stain PCM outside panel

The present invention relates to a polyester coating composition for non-pollution PCM exterior materials, and more particularly, to a hydroxy unsaturated polyester resin and a melamine curing agent, including secondary amine shielding or epoxy resin shielding sulfonic acid; Tertiary amine masked sulfonic acids; Isocyanate compounds masked with malonates; Tin curing catalysts; Polyalkylsilicates; In addition, since the alkoxy compound is contained in a certain content ratio, the surface density, fouling resistance, acid resistance and self-cleaning ability of the coating film are excellently improved, and the compatibility of the hydroxy unsaturated polyester resin and polyalkyl silicate is also improved. The present invention relates to a polyester coating composition for non-pollution PCM exterior material which obtains another effect of improving coating appearance properties and workability without additional defoaming agent and leveling agent.

Recently, high-functionalization technology related to the environment has attracted much attention, and accordingly, demands for PCMization of home appliances and special pollution indoors and outdoors are increasing in the PCM field. There is an increasing demand for contaminating paints.

Looking at the structure that is currently used as architectural exterior materials, it can be divided into high-end building for low-rise and low-end building for low-rise. In the case of high-rise buildings, long-term durability is required in consideration of the durability of the building. Therefore, paints using high-durability fluorine resin are mainly used, and because of the aesthetic value of the building, the building is continuously maintained by washing. It is true. On the other hand, in low-rise buildings with low floors, the durability of the building is set low from the beginning. Therefore, there is almost no function of maintaining the cleanliness of the building.In the case of low-rise buildings, polyester melamine-type coatings have a low durability. It is built using prepainted steel sheets. In this case, in addition to the durability of the coating film and the prevention of penetration of contamination, the property of maintaining the initial appearance of the building is very important. In other words, even if contaminants are deposited on the constructed steel sheet, there is an urgent need for a strong self-cleaning coating film that can be cleaned by rain.

In order to achieve the above object, the present applicant has developed a self-cleaning type PC steel sheet and has applied for a patent [Korea Patent Publication No. 2000-47283]. In addition, it was pointed out that the effect of the coating film was not excellent because the weatherability of the coating film was not excellent for more than two years. Also, due to the excessive content of the melamine crosslinking resin contained to improve the crosslinking density of the coating film, There are many cases where the change is large and the workability is poor, and when the coated steel plate collides with another iron plate, there is a disadvantage that a black mark is generated on the surface of the coating film.

As a conventional technique for preventing rain water pollution, tetramethoxysilane is hydrolyzed and condensed under a hydrolysis rate of less than 100% to obtain a molar ratio of silanol and methoxysilyl groups ([SiOH] / [SiOMe]) of 1/10 or less, Coating compositions comprising a partially hydrolyzed condensate of tetramethoxysilane containing tetramethoxysilane having a content of 2 to 8 monomers of 0 to 30% by weight and a weight average molecular weight of 1500 to 5000 are known [US Patent 6,013,721]. In general, in the case of a paint containing a silicate compound having a silanol group bonded thereto, the hydrophilic property facilitates the penetration of a water-soluble oxide such as a chemical into a metal substrate, thereby lowering chemical resistance and reducing the hydroxyl resistance of the resin and the silanol group (SiOH). Problems such as deterioration of storage stability due to rapid reaction and deterioration of MAGIC contamination are pointed out.

Thus, in the present invention, in order to improve the above problems, the hydroxy unsaturated polyester resin and melamine curing agent having excellent weather resistance are mainly composed of secondary amine shielding or epoxy resin shielding sulfonic acid; Tertiary amine masked sulfonic acids; Isocyanate compounds masked with malonates; Tin curing catalysts; Polyalkylsilicates; In addition, by containing alkoxy compound in a certain content ratio, it is very resistant to external pollutants and provides a polyester coating composition for non-contaminated PCM exterior material which can greatly improve the durability of coating by fundamentally preventing the infiltration of pollutants. Its purpose is to.

In addition, when the molecular weight of the hydroxy unsaturated polyester resin and the polyalkyl silicate contained in the coating composition of the present invention is adjusted to an appropriate range, the coating film appearance characteristics even without adding a defoaming agent and a leveling agent And workability improvement.

The present invention relates to a polyester coating composition containing a hydroxy unsaturated polyester resin, a melamine curing agent, a curing accelerator, an auxiliary curing agent, an auxiliary curing accelerator, a storage stabilizer, and a curing catalyst.

Hydroxy unsaturated polyester resin 40 to 80% by weight; 5-50% by weight of melamine curing agent; 0.5 to 3 wt% secondary amine shielding or epoxy resin shielding sulfonic acid; 0.001 to 3 weight percent tertiary amine masked sulfonic acid; 1 to 10% by weight of isocyanate compounds masked with malonate; 0.1 to 2 wt% of a tin-based curing catalyst; 0.5 to 10% by weight of polyalkyl silicate represented by the following formula (1); And it characterized by the polyester coating composition for non-contamination PCM exterior materials which contains 1-5 weight% of alkoxy compounds.

In Formula 1, R ₁ , R ₂ , R ₃ , R ₄ , R _5, and R ₆ are the same as or different from each other and represent a lower alkyl group having 1 to 5 carbon atoms; n represents the integer of 5-80.

The present invention will be described in more detail as follows.

The present invention has a hydroxy unsaturated polyester resin and a melamine curing agent as a main component, and as the curing accelerator, secondary amine shielding or epoxy resin shielding sulfonic acid; Tertiary amine masked sulfonic acids as co-curing accelerators; Isocyanate compounds masked with malonates as co-curing agents; Tin curing catalysts; Polyalkyl silicates represented by Formula 1 as surface modifiers; In addition, by containing alkoxy compound as a storage stabilizer in a certain content ratio, it is very resistant to external contaminants, and prevents the internal penetration of contaminants, thereby greatly improving the durability of the coating film. It is about.

Hereinafter, the respective compositions contained in the coating composition according to the present invention will be described in more detail.

The hydroxy unsaturated polyester resin is a polyester resin having a hydroxyl group, and in the present invention, unsaturated polyesters, oil modified polyesters and urethane modified unsaturated polyesters or urethane modified oil modified polyesters thereof may be used. . The hydroxy unsaturated polyester resin according to the present invention preferably has a number average molecular weight of 1500 to 8,000, a glass transition temperature of -15 to 60 ° C, and a hydroxyl value (OH Value) of 15 to 180, more preferably. A hydroxy unsaturated polyester resin having a number average molecular weight of 2,000 to 7,000, a glass transition temperature of -5 to 45 ° C, and a hydroxyl group of 20 to 150 is used.

The oil-modified polyester of the present invention can be prepared by the reaction of a polybasic acid and a polyhydric alcohol, wherein the polybasic acid is alicyclic acid, phthalic anhydride, isophthalic acid, terephthalic acid, succinic acid, adipic acid, fumaric acid, maleic anhydride, tetra Hydrophthalic anhydride, hexahydro phthalic anhydride, and derivatives thereof may be used, and when excessive use of a compound having a double bond, such as isophthalic acid, may cause a problem of poor weather resistance when forming a film, preferably alicyclic acid, such as Preference is given to using linear acids without benzene rings. As the polyhydric alcohol, ethylene glycol, propylene glycol, diethylene glycol, butanediol, neopentyl glycol, 3-methylpentanediol, 1,4-hexanediol, 1,6-hexanediol, and the like are used. can do.

The urethane-modified polyester resin may be prepared by the reaction of the oil-modified polyester resin and a polyisocyanate compound. The polyisocyanate compound may be hexamethylene diisocyanate, isophorone diisocyanate, xylene diisocyanate, toluene die. Isocyanate, 4,4'- diphenylmethane diisocyanate, 4,4'- methylenebis (cyclohexyl isocyanate), 2,4,6-triisocyanate toluene, and derivatives thereof can be selected and used.

In the present invention, it is preferable to use the hydroxy unsaturated polyester resin in 40 to 80% by weight of the total coating composition, if the content is less than 40% by weight, the flexibility and impact resistance of the coating film is greatly reduced, 80% by weight If it exceeds, there exists a problem that the fouling resistance, solvent resistance, and hardness of a coating film fall rapidly.

In the present invention, a melamine resin is used as a curing agent, which may be a methoxy melamine resin having a molecular weight of 300 to 1000, or a methoxy / butoxy mixed type. The methoxy melamine resin is obtained by polymerization of methanol and formaldehyde. Examples of commercially available methoxy melamine resins used in the present invention include CYMEL-303, CYMEL-325, CYMEL-327, CYMEL-350, CYMEL-370 (CYTEC), RESIMINE-7550, RESIMINE-717, RESIMINE-730 , RESIMINE-747, RESIMINE-797 (SOLUTIA), BE -3717, BE-370, BE-3747 (BIP). Examples of the butoxy / methoxy mixed resin include RESIMINE-755, RESIMINE-757, RESIMINE-751 (SOLUTIA), CYMEL-1168, CYMEL-1170, and CYMEL-232 (CYTEC).

In the present invention, it is preferable to use the methoxy type melamine resin or the methoxy / butoxy mixed melamine resin as the melamine resin, but the butoxy melamine resin is used alone, or the methoxy melamine and the butoxy melamine resin mixed melamine resin When methoxy melamine and butoxy melamine resin are simply used in combination, the compatibility with polyester resin is drastically reduced, and the melamine is transferred to the upper layer of the paint, which lowers the non-pollution property of the coating film and also the gloss of the coating film. Will fall.

In the present invention, it is preferable to use the melamine curing agent in an amount of 5 to 50% by weight based on the total coating composition. If the content of the melamine curing agent is less than 5% by weight, the fouling resistance and solvent resistance are drastically lowered, and the content is 50% by weight. When it exceeds%, the softness and impact resistance of a coating film fall and it is unpreferable. Since the methoxy type melamine resin or the methoxy / butoxy mixed type melamine resin is smaller than the butoxy type in its molecular weight, it is easy to thicken the melamine on the surface, and thus the melamine self-condensation or the number of the surfaces when the tertiary amine dissociates. Hardening with a stratified layer is fulfilled, and an overall hardened coating film can be obtained.

In addition, in the present invention, by containing a curing accelerator to promote the curing of the polyester resin and melamine curing agent to improve the density of the coating film, wherein the curing accelerator may be a secondary amine shielding or epoxy resin shielded sulfonic acid. As the sulfonic acid, p-toluenesulfonic acid, dodecylbenzenedisulfonic acid, dinonylnaphthalenedisulfonic acid, dinonylnaphthalenesulfonic acid, and the like may be used, and among these, it is preferable to use p-toluenesulfonic acid or dinonylnaphrenylene sulfonic acid. The sulfonic acid is preferably shielded with a material that can be dissociated by heat, and as the shielding material, secondary amine or epoxy resin is used. In addition to secondary amines, primary or tertiary amines may be used as the sulfonic acid shielding material, but primary amines cause color changes such as yellowing in the coating film, and tertiary amines generally cause shrinkage of the coating film surface when used in excess. It is preferable to use a secondary amine as the shielding material of sulfonic acid because of the disadvantage. Examples of the secondary amine include diethylamine, diisopropylamine, diisopropanolamine, di-n-propylamine, di-n-butylamine, isobutylamine, di-secondary-butylamine, diallylamine Diamylamine, N-ethyl-1,2-dimethylpropylamine, N-methylhexylamine, di-n-octylamine, piperidine, 2-pipecoline, 3-piecholine, 4-pie Choline, morpholine, and the like, and by adding an effective amount of these to the composition, it was possible to greatly increase the stain resistance of the coating film.

In the present invention, the curing accelerator is contained in an amount of 0.5 to 3% by weight, preferably 0.5 to 2% by weight, of the total coating composition. If the content of the curing accelerator is less than 0.5% by weight, the curing of the coating film is insufficient according to the working conditions can not maintain the proper fouling resistance, if it exceeds 3% by weight the curing of the coating film occurs too rapidly to the coating film during painting work Popping occurs or shrinkage of the coating film occurs.

Among the pollutants of the coating film, a strong inorganic pollutant is embedded in the coating film. In order to remove such pollutants, densification of the coating film is required. However, if the coating is too dense, the flexibility is poor, which leads to the poor workability required for PCM (pre-coated metal). In order to solve this problem, it is necessary to form a coating structure, that is, a multi-layer structure, in which the coating film is flexible all over but has a dense surface.

In the present invention, by containing an auxiliary curing accelerator, while reducing the content of the melamine curing agent, by densifying the surface of the coating film, it is possible to improve the magic resistance of contamination and to prevent the generation of metal marks generated when metals collide with each other. As a result, when the dense property of the surface using the auxiliary curing accelerator and the hydrophilic property using the surface modifier are applied together, it is possible to prepare a paint having the property of simultaneously blocking the organic / inorganic pollution source in the flexible coating.

As the secondary curing accelerator, sulfonic acid shielded with tertiary amine is used. The volatility of the coating layer is increased by helping to rapidly cure at the surface due to high volatility. The sulfonic acid is of a kind similar to that described in the above curing accelerator, and tertiary amines include trimethylamine, triethylamine, and the like as the sulfonic acid shielding material.

In the present invention, the auxiliary curing accelerator contains 0.01 to 3% by weight of the total coating composition, when the content is less than 0.01% by weight, the effect of promoting the surface film hardening and the effect of preventing the metal mark is inhibited, 3% by weight If it exceeds, the surface of the coating film is contracted, and the effect disappears.

In the present invention, an isocyanate compound that is masked with malonate and masked so that room temperature curing does not occur is used as an auxiliary curing agent. Such co-curing agent blocks the chemical-resistant coating film formation and moisture material penetration through the urethane reaction with the resin. Isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HMDI), hexamethylene diisocyanate trimer (Trimer HMDI), etc. can be used as an isocyanate compound. It is preferable to use an isocyanate compound which does not have a yellowing phenomenon, that is, a double bond, is suitable for the thermosetting type, and such products include Desmodure BL 3575, BL1203 (manufactured by BAYER), R6711, R6730, R6720, R6710 (manufactured by KCC). Products). As the isocyanate compound used as the co-curing agent of the present invention may be severely yellowed in the coating film by an acid curing agent used together, it is preferable to use isocyanate masked with malonates such as ethyl malonate.

In the present invention, the co-curing agent contains 1 to 10% by weight, preferably 3 to 7% by weight, of the total coating composition. When the content is less than 1% by weight, the effect of improving the acid resistance of the coating film is less than 10% by weight. This increases the raw material cost of the paint.

In the present invention, a tin-based catalyst is used as the curing catalyst, and the product includes DBTDL Stan BL (Japan catalyst product). The curing catalyst is contained in the total coating composition of 0.1 to 2% by weight, preferably 0.5 to 1% by weight. When the content of the curing catalyst is less than 0.1% by weight, the effect as a catalyst is lowered, and the effect of improving acid resistance is lowered. When used in excess of 2% by weight, yellowing occurs and the cost of the raw material of the paint is increased.

In addition, in the present invention, by containing a polyalkyl silicate represented by the formula (1) as a surface modifier of the coating film, by applying a hydrophilic group to the surface of the coating film to self-purification ability to float the contaminants on the surface of the water (Self There is a cleaning effect. Some conventional patents contain silicate compounds in which silanol groups (SiOH) and methoxysilyl groups (SiOMe) are present in a certain content ratio as surface modifiers in non-polluting PCM coating compositions. There is a problem in storage stability because it reacts with hydrophilic drugs or moisture in the air before. On the contrary, the polyalkyl silicate represented by Chemical Formula 1 used as the surface modifier of the present invention does not contain any silanol group (SiOH), so it is excellent in chemical resistance and storage stability, and after coating, It is also excellent in self-purifying ability because it is converted to hydrophilic material having hydroxyl group (OH) which lowers the water contact angle by rain water. In other words, the silicate is floated to the surface of the coating film as much as possible to block the penetration path of moisture. The molecular weight of the silicate is used in the 4,000 ~ 10,000, and when it is less than 4,000, the mixed with the resin is high, the surface injury effect and workability of the methoxysilyl group is lowered. Is lowered. In addition, if the compatibility of the hydroxy unsaturated polyester resin used as the main resin and the polyalkyl silicate represented by the formula (1) is properly adjusted, the coating film may be added even without adding a deforming additive and a leveling additive. Since the effect of improving the appearance characteristics and workability can be obtained, it is very advantageous industrially. These additives are generally low and non-responsive relative to the surface tension of the silicates and thus serve to counteract the surface injury of the silicates.

By maintaining the molecular weight ratio of the hardoxy unsaturated polyester resin and the polyalkyl silicate represented by the formula (1) in the range of 1: 0.8 to 3.0, it is possible to obtain an effect of improving the coating appearance properties and workability without a separate antifoaming agent and a leveling agent. have. If it is out of the above range, the problem of compatibility, workability degradation, chemical resistance degradation, paint entanglement, gloss degradation occurs.

The polyalkyl silicate represented by Formula 1 preferably has a degree of polymerization of 5 to 80 as a substance in which an alkyl group is substituted in the main chain and the side chain. If the degree of polymerization is less than 5, the surface modification effect is greatly reduced, and the degree of polymerization exceeds 80. If the paint storage stability and workability is poor. As the alkyl group introduced into the main chain and the side chain of the polyalkyl silicate, a methyl group or an ethyl group may be substituted. Examples of commercially available polyalkylsilicates which can be used in the present invention include methyl silicate 51 (Colcote), ethyl silicate 40 (Huls), methyl silicate 51, methyl silicate 56, methyl silicate 56 (S), methyl silicate 57 ( Mitsubishi Chemical Co., Ltd.), and it is preferable to use a methyl silicate system in the present invention.

In the present invention, the surface modifier is contained 0.5 to 10% by weight, preferably 1 to 7% by weight of the total coating composition. If the content of the polyalkyl silicate is less than 0.5% by weight, the self-cleaning effect of the coating film is significantly lowered. If the content of the polyalkyl silicate is more than 10% by weight, the raw material cost of the paint is increased and the stability of the paint is lowered.

The reaction rate between methoxy silyl groups (SiOMe) is stable when relatively no moisture, but there is a characteristic that a rapid reaction occurs in the presence of moisture or in the presence of a hydroxyl group (-OH) of the resin. Therefore, the hydroxyl group of the resin in the paint should be shielded or the moisture content should be minimized. In the present invention, it is necessary to shield the hydroxyl group (-OH) contained in the hydroxyl group (-OH) and other composition components of the main resin, and for this purpose, an alkoxy compound is contained as a storage stabilizer. When the alkoxy compound contains a mass average molecular weight of 100 to 1000, when the mass average molecular weight is less than 100, the storage stability is deteriorated. When the alkoxy compound exceeds 1000, an excess is added to cure the coating film. Inferior defects will occur. Examples of alkoxy compounds that can be used in the present invention include KBM 13, manufactured by Shin Nitsu, Japan, trimethyl ortho formate, Huyl, USA, triethyl ortho formate, trimethyl ortho acetate, and BAIDER, Germany. ADDITIVE TI.

In the present invention, the storage stabilizer is contained in 1 to 5% by weight of the total coating composition, when the content is less than 1% by weight, the storage stability effect is insignificant, and when used in excess of 5% by weight, a dense coating film causes the price increase and hardening inhibition There is a disadvantage that can not form.

On the other hand, the polyester coating composition for PCM packaging material according to the present invention containing a composition component as described above may be used as a transparent coating without using a pigment, it may be formed by using an organic or inorganic pigment. . As the pigment used as the colored paint, it is preferable to use a pigment capable of imparting heat resistance and chemical resistance suitable for PCM paint. In addition, the basic particles of the pigment should also be considered sufficiently, such pigments include cyanine blue, titanium oxide white, iron oxide red, carbon black, chrome yellow and the like. In addition, sieving pigment, minusil, talc, cray, silica compounds and the like can be used.

Cold rolled steel, zinc hot dipping steel, electro-zinc steel, alloy-plate steel, copper sheet and tin-plate steel, etc. may be used as the material used for the coating in the present invention, and the material used mainly as a master Cold rolled steel (CR), electro zinc steel (EGI), zinc hot dipping steel (GI), alloy plate steel (GA) and the like.

In addition, phosphate, chromate, or the like may be used as a pretreatment of the material used, and as the degree of material adhesion, an epoxy type primer, a polyester type primer, an acrylic type primer, or a modified form thereof may be used. Among them, epoxy type primers are most preferred.

As the coating method of the paint according to the present invention, curtain coating, roll coating, immersion coating, spray coating, and the like can be used, and the coating thickness used for coating is preferably 5 to 25 µm. In addition, the baking time can be changed according to the baking conditions, it is preferable to bake for 35 to 40 seconds in the atmosphere conditions of 250 ~ 280 ℃ in the painting conditions of the PCM.

When the present invention is described in detail based on the following examples, the present invention is not limited to the examples.

Examples 1-16 and Comparative Examples 1-6

The polyester coating composition was formulated according to the compositions and contents of the following Tables 1a and 1b, and EJ2751-Y005 (Korea Chemical Products), an epoxy-modified polyester primer, was coated with a thickness of 5 to 7 μm, and the baking condition was 280 ° C. It was painted at 2 m x 22 seconds and the wind speed, and the maximum temperature of the sobush was adjusted to 210-216 ° C. At this time, the coating method was a bar coating, and bar No. # 14 was used. In the case of baking, the automatic drying oven manufactured by Korea Taesung Engineering was used as the baking. The material used for painting was a 0.45 mm galvanize iron (GI) material manufactured by POSCO Gwangyang Bay, and the zinc content of the material was 87 mg / m 2. The material pretreatment of the GI material was subjected to NRC (Non Rinse Chromate; manufactured by Faragaising Co., Ltd.), the throughput was applied to 20 ~ 40 mg / ㎡.

In addition, the composition of the following Table 1a and Table 1b was prepared based on the solid content, the solvent used in the paint was excluded. Solvents used in paints were used to control the fluidity and viscosity required to prepare the paints.

Manufacture of M / B (Mill / Base)

To each polyester resin, add 1/1 mixed solution of cyclohexane (Kodak product) / Cocosol # 100 (KOCOSOL) (porous product) as a solvent to make 70% solids, and add TiO ₂ (Ishihara, Japan or DuPont) and dispersant NUOSPERSE 657 (3 g, BYK) were placed in a 1 L tin container, and then 1 to 2 mm glass beads (GLASS BEAD) were mixed in the solution, and a shake type disperser (Korea Chemical Co., Ltd., product name) RED DEVIL) for 1 hour 30 minutes. The particle size after dispersion was adjusted to 5 μm or less.

Manufacture of L / D (Let / Down)

The ratio of pigment / resin was added to M / B prepared above by adding resin / curing agent / curing accelerator / secondary curing accelerator / curing catalyst / surface modifier / storing stabilizer in accordance with the combination of Table 1a and Table 1b. The viscosity of the final paint was adjusted to 100 seconds / Ford Cup # 4, 25 ° C.

Furtherance product name Example (g) Comparative Example (g) One 2 3 4 5 6 7 8 One 2 3 Polyester resin Lexorex C906-85 ¹⁾ 70 80 70 85 Chempol 11-1645-A ²⁾ 50 70 SN-830 ³⁾ 60 80 SN-805 ⁴⁾ 75 75 60 Melamine curing agent cymel 303 ⁸⁾ 30 25 25 40 20 cymel 325 20 30 cymel 1168 ⁹⁾ 50 30 15 cymel 370 ¹⁰⁾ 40 Curing accelerator Nacure 1953 ²⁵⁾ 3 3 2 2.5 2.5 One Nacure 1419 ²⁶⁾ 3 3 One 2.5 3.5 3 Auxiliary curing accelerator Nacure 2107 ²⁷⁾ 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Auxiliary hardener R6711 ²¹⁾ 5 5 5 5 5 5 5 5 5 R6730 ²²⁾ 5 BL3175 ²³⁾ 5 Curing catalyst DBTDL ³⁰⁾ 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Surface modifier MS-51 ¹⁶⁾ 10 10 20 10 MS-56 ¹⁷⁾ 10 10 12 10 12 5 ACZ42631 ¹⁸⁾ 10 Storage stabilizer TEOF ³¹⁾ 2 3 3 3 TMOA ³²⁾ 2 2 2 KBM-13 ³³⁾ 3 3 3 Leveling agent Polyfolw 90-50 ³⁵⁾ One Dispalon L1980 ³⁶⁾ One One Pigment Per party 125 125 125 125 125 125 125 125 125 125 125

Furtherance product name Example (g) Comparative Example (g) 9 10 11 12 13 14 15 16 4 5 6 Polyester resin Lexorex C906-85 ¹⁾ 70 70 CRF0003 ⁵⁾ 80 70 60 85 Wire diameter A960 ⁶⁾ 60 75 60 80 R3310 ⁷⁾ 70 Melamine curing agent Resimine 747 ¹²⁾ 30 20 40 40 40 15 Resimine 7512 ¹³⁾ 30 Resimine 797 ¹⁴⁾ 30 30 25 Beetle BE630 ¹⁵⁾ 30 Curing accelerator Nacure 1953 ²⁵⁾ 3 3 2 3 1.5 2 Nacure XP-383 ²⁸⁾ 3 3 One 3 3 Auxiliary curing accelerator Taycacure AC3401 ²⁹⁾ 0.2 0.2 0.2 0.2 0.2 Nacure 2107 ²⁷⁾ 0.1 0.1 0.1 0.1 0.1 0.1 Auxiliary hardener R6711 ²¹⁾ 5 5 5 5 5 5 5 5 5 B-1370 ²⁴⁾ BL3175 ²³⁾ 5 Curing catalyst DBTDL ³⁰⁾ 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Surface modifier MS-56 (S) ¹⁹⁾ 10 10 20 MS-57 ²⁰⁾ 10 10 12 10 12 10 5 ACZ42631 ¹⁸⁾ 10 Storage stabilizer KBM-13 ³³⁾ 3 3 3 TEOF ³¹⁾ 3 3 3 3 3 ADDITIVE TI ³⁴⁾ 2 2 3 Leveling agent Polyfolw 90-50 ³⁵⁾ One One Dispalon L1980 ³⁶⁾ One Pigment Per party 125 125 125 125 125 125 125 125 125 125 125

(week)

1) Leolex C906-85: product manufactured by Inolex, Tg -10 ℃, hydroxyl value (OH Value) 90, number average molecular weight 1500

2) CHEMPOL 11-1645-A: product made by CCP, Tg -5 ℃, hydroxyl value (OH Value) 60, number average molecular weight 4500

3) SN-830: DSM's product, Tg 32 ℃, OH value 40, number average molecular weight 4500

4) SN-805: DSM's product, Tg 0 ℃, OH value 85, number average molecular weight 3000

5) CRF00031: manufactured by KCC, Tg 38 ℃, hydroxyl value (OH Value) 55, number average molecular weight 4000

6) Wire diameter A960: Product of wire diameter, Tg 20 ℃, OH value 20, number average molecular weight 8000

7) R3310: manufactured by KCC, Tg 35 ℃, hydroxyl value (OH Value) 60, number average molecular weight 3500

8) CYMEL 303: A product of CYTEC, a melamine resin of FULL METHOXY MELAMINE TYPE having a molecular weight of 1000 or less and a solid content of 98%.

9) CYMEL 325: CYTEC Co., Ltd., a methoxymelamine resin of HIGH IMINO TYPE with 80% solids.

10) CYMEL 1168: A methoxy-butoxy mixed melamine resin with 95% solids, manufactured by CYTEC.

11) CYMEL 370: Melamine resin manufactured by CYTEC, having methoxymethyl-methylol group with 88% solids.

12) RESIMINE 747: A SOLUTIA product, a melamine resin of FULL METHOXY MELAMINE TYPE with a molecular weight of 1000 or less and a solid content of 98%.

13) RESIMINE 7512: SOLUTIA product, melamine resin of FULL BUTHOXY MELAMINE TYPE with 95% solids.

14) RESIMINE 797: SOLUTIA, a methoxymelamine resin modified with highly reactive 20% styrene allyl alcohol. Modified METHOXY MELAMINE resin, SOLUTIA product.

15) BEETLE BE630: A melamine resin of FULL BUTHOXY MELAMINE TYPE, made by BEETLE, 95% of solid content.

16) MS-51: manufactured by Colcoat or Mithubith Chemical of Japan, methyl silicate represented by the formula (1), polymerization degree of about 5 to 10.

17) MS-56: manufactured by Mithubith Chemical of Japan, methyl silicate represented by the formula (1), polymerization degree of about 10 to 20.

18) ACZ42631: Kumkang Korea Chemical Co., Ltd., ethyl silicate / ethylsilane (SiOH), polymerization degree of about 20 to 30.

19) MS-56 (S): manufactured by Mithubith Chemical of Japan, methyl silicate represented by the formula (1), polymerization degree of about 30 to 40.

20) MS-57: The product made by Mithubith Chemical of Japan, the methyl silicate represented by General formula (1), and the polymerization degree about 20-30.

21) Kisogang Korea Chemical Co., Ltd., isophorone diisocyanate (IPDI) blocked with ethyl malonate.

22) Hexamethylene diisocyanate (HMDI) in trimer form blocked with Methyl ethyl ketone, Kumgang Korea Chemical Co., Ltd.

23) Hexamethylenediisocyanate (HMDI) in trimer form blocked with Methylethylketone from BAYER.

24) Isophorone diisocyanate (IPDI) blocked with methyl ethyl ketone from HULS.

25) Nacure 1953: dinonylsulfonic acid masked with secondary amine, dissociation temperature of above 140 ° C.

26) Nacure 1419: DINONYL Sulfonic acid masked by KING, epoxy resin, dissociation temperature is more than 160 ℃.

27) Nacure 2107: product of KING, p-toluenesulfonic acid masked with tertiary amine, dissociation temperature of more than 115 ℃.

28) Nacure XP-383: A product of KING, a dinonylsulfonic acid masked with epoxy resin, whose dissociation temperature is over 120 ℃.

29) Taycacure AC3401: Dodecyl benzenesulfonic acid masked with tertiary amine, manufactured by Tayca, Japan, with dissociation temperature of 140 ° C or higher.

30) DBTDL: Tin catalyst based on Songwon Industrial Co., Ltd.

31) TEOF: Triethyl orthoformate, manufactured by HULS, USA.

32) TMOA: Trimethyl ortho acetate, manufactured by HULS, USA.

33) KBM-13: Methyltrimethoxysilane, manufactured by Shin-Nitsu, Japan.

34) ADDITIVE TI: 4-toluenesulfonyl isocyanate, manufactured by Bayer, Germany.

35) Polyflow No 90-50: Japanese level company, acrylic leveling agent.

36) Dispalon L-1980: Made in Japan by Gusumoto, Acrylic Leveling Agent.

Experimental Example: Property Test

After coating the coating compositions of Examples 1 to 16 and Comparative Examples 1 to 6 (Bar # 26), a coating film was prepared by baking in an automatic discharge oven for 30 seconds at 280 ° C. The physical properties of each coating film were measured by the following method, and the results are shown in the following Tables 2a and 2b.

[Experimental method]

1. Gloss (GLOSS 60 °): 60 ° gloss was measured using a BYK or SHEEN company.

2. Hardness: Scratch of coating film was evaluated using Japan Mitubishi Uni Pensil.

3. Magic pollution: 1 hour after coating on the surface using Monami magic, and wiped the surface with methanol to evaluate △ E of the remaining traces.

4. Workability: Two sheets of material having the same thickness as the material were put at room temperature and processed 180 °, and the peeled state and the crack state were evaluated by winding the processed part with Scotch tape.

(Score: no crack 5 ←, → 1 crack is generated and peeled off entirely)

5. Acid resistance: 5% hydrochloric acid solution was applied to the coating film, the surface was covered and the surrounding was shielded with petroleum jelly, which was left at 25 ℃ for 24 hours, the state of the coating film was evaluated.

(Score: no trace 5 ←, → 1 peeling)

6. Base resistance: 5% sodium hydroxide solution was applied to the coating film, the surface was covered and the surrounding was shielded with petrolatum, it was left at 25 ℃, 24 hours, and the state of the coating film was evaluated.

(Score: no trace 5 ←, → 1 peeling)

7. Carbon pollution: After mixing and stirring 10% of carbon black in distilled water, it was sprayed on the coating film and left for 24 hours at 80 ℃. The specimen thus left was cooled and then washed with running water with a soft brush to record the color difference (ΔE).

8. Evaluation of QUV 500 hours gloss retention: Using a QUV-se device manufactured by US Q-PANEL, the UV wavelength was adjusted to B Type (313 nm), and the cycle was irradiated at 60 ° C. for 8 hours and 40 ° C. for 4 hours. The retention rate was evaluated by condensing and comparing the gloss after the initial gloss test of the coating film.

9. Storage stability: After measuring the initial viscosity of the paint and left in an oven at 60 ℃ for 7 days, after evaluating the viscosity change of the stored paint, the change in the degree of coating film curing was evaluated.

10. Outdoor exposure pollution resistance test: The coating film was turned 45 ° and then exposed to the outdoors, and the contamination status after exposure was compared to evaluate ΔE.

Test Items Example (g) Comparative Example (g) One 2 3 4 5 6 7 8 One 2 3 GLOSS (60 °) 94 95 86 97 94 90 92 93 91 86 96 Hardness (Mit-Uni Pencil) 2H 2H H H 2H H 2H 2H H H H Magic pollutant △ E (monami) 0.5 0.8 1.3 1.2 0.5 1.0 0.6 0.3 0.3 0.5 4.6 Machinability (2T, Taping) 4 4 5 4 4 4 4 4 4 4 4 HCl 5% 24 hours 5 5 5 5 5 5 5 5 4 4 4 NaOH 5% 24 hours 5 5 5 5 5 5 5 5 4 4 4 Carbon Pollutant △ E 0.3 0.5 1.1 1.0 0.4 1.0 0.5 0.3 3.8 3.0 4.6 Q.U.V 500 hours GR (%) 44 35 40 45 40 45 45 40 45 40 35 Storage stability O ◎ ◎ ◎ O O ◎ ◎ X X O Outdoor exposure pollution resistance (△ E) 1.7 0.5 1.9 1.0 1.6 1.2 1.5 1.4 7.8 3.2 0.9

Test Items Example (g) Comparative Example (g) 9 10 11 12 13 14 15 16 4 5 6 GLOSS (60 °) 94 84 85 86 94 90 92 93 91 45 40 Hardness (Mit-Uni Pencil) 2H H H F 2H H 2H 2H F H HB Magic pollutant △ E (monami) 0.4 0.7 0.5 1.2 0.5 1.0 0.4 0.2 0.8 3.8 2.0 Machinability (2T, Taping) 4 5 5 5 4 4 4 3 5 5 5 HCl 5% 24 hours 5 5 5 5 5 4 5 5 2 4 4 NaOH 5% 24 hours 5 5 5 5 5 5 5 5 3 4 4 Carbon Pollutant △ E 0.3 0.5 1.2 1.3 0.4 1.0 0.3 0.1 4.0 3.5 4.6 Q.U.V 500 hours GR (%) 43 95 95 20 44 45 47 45 25 26 28 Storage stability ◎ ◎ ◎ O O ◎ ◎ ◎ O X ◎ Outdoor exposure pollution resistance (△ E) 0.3 0.5 1.5 0.5 0.5 0.1 1.5 1.4 7.8 5.5 9.9

As described above, the polyester coating composition for non-pollution PCM exterior material according to the present invention is a PCM coating composition mainly comprising a high weather-resistant hydroxy unsaturated polyester resin and a melamine curing agent using an acid monomer without benzene ring. Secondary amine masked or epoxy resin masked sulfonic acids; Tertiary amine masked sulfonic acids; Isocyanate compounds masked with malonates; Tin curing catalysts; Polyalkylsilicates; In addition, since the alkoxy compound is contained in a predetermined content ratio, it is useful for painting steel sheets of building exterior materials for PCs because of excellent pollution resistance, acid resistance, weather resistance, and self-cleaning ability. In particular, if the molecular weight range of the hydroxy unsaturated polyester resin used as the main resin and the polyalkyl silicate used as the surface modifier is properly maintained, the coating film appearance characteristics and workability can be improved without the addition of a separate antifoaming agent and a leveling agent. do.

Claims (7)

A polyester coating composition containing a hydroxy unsaturated polyester resin, a melamine curing agent, a curing accelerator, an auxiliary curing agent, an auxiliary curing accelerator, a storage stabilizer, and a curing catalyst, Hydroxy unsaturated polyester resin 40 to 80% by weight; 5-50% by weight of melamine curing agent; 0.5 to 3 wt% secondary amine shielding or epoxy resin shielding sulfonic acid; 0.001 to 3 weight percent tertiary amine masked sulfonic acid; 1 to 10% by weight of isocyanate compounds masked with malonate; 0.1 to 2 wt% of a tin-based curing catalyst; 0.5 to 10% by weight of polyalkyl silicate represented by the following formula (1); And 1 to 5% by weight of the alkoxy compound. Formula 1 In Formula 1, R ₁ , R ₂ , R ₃ , R ₄ , R _5, and R ₆ are the same as or different from each other and represent a lower alkyl group having 1 to 5 carbon atoms; n represents the integer of 5-80. The method of claim 1, wherein the hydroxy unsaturated polyester resin has a number average molecular weight (Mn) of 800 to 15,000, a glass transition temperature (Tg) of -15 ℃ to 60 ℃, the hydroxyl value (OH Value) of 15 ~. Polyester coating composition for non-pollution PCM exterior material, characterized in that 180. The polyester coating composition of claim 1, wherein the melamine curing agent is a methoxy melamine resin or a methoxy / butoxy mixed melamine resin. The isocyanate compound masked with malonate is an isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HMDI) or hexamethylene diisocyanate trimer. (Trimer HMDI) polyester coating composition for non-pollution PCM exterior material, characterized in that. According to claim 1, wherein the number average molecular weight (Mn) of the hydroxy unsaturated polyester resin is in the range of 800 to 15,000 and at the same time by adjusting the molecular weight of the polyalkyl silicate represented by the formula (1) in the range of 5,000 to 10,000 further leveling agent and Polyester coating composition for non-pollution PCM exterior material characterized in that the antifoaming agent is not added. The non-polluting agent according to claim 1, wherein the hydroxy unsaturated polyester resin and the molecular weight ratio of the polyalkyl silicate represented by the formula (1) are adjusted in the range of 1: 0.8 to 3.0 so as not to add a leveling agent and an antifoaming agent. Polyester coating composition for PCM exterior material. Steel sheet, characterized in that the coating composition of claim 1 is coated.