JP2014012748A - Stain-resistant metallic coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stain-resistant metallic coating composition that can form coating films excellent in stain resistance to rainwater, weather resistance and processability, particularly a stain-resistant metallic coating composition suitable to form topcoat films on metal plates.SOLUTION: The stain-resistant metallic coating composition is a coating composition comprising: a particular polyester resin component; a cross-linker component, a melamine resin and/or a polyisocyanate compound; an organosilicate component and/or a surfactant component; and a metallic pigment component.

Description

  The present invention is a stain resistant metallic paint composition capable of forming a coating film excellent in stain resistance, weather resistance and processability against rainwater, etc., particularly a stain resistant metallic paint composition suitable for forming a top coat film of a coated metal plate, The present invention relates to a method for forming a coating film having excellent stain resistance using the coating composition, and a coated metal plate on which a cured coating film is formed from the coating composition.

  Conventionally, outdoor base materials (for example, buildings, display objects, guard fences, appliances, machines, etc.) have been coated with an outdoor paint excellent in weather resistance for the purpose of decoration or protection. Examples of paints used outdoors include polyurethane resin paints, fluororesin paints, silicon resin paints, acrylic resin paints, polyester paints, etc., but these paints are exposed outdoors. As a result, there has been a drawback that the surface of the coated material is easily soiled due to the influence of dust, iron powder, rain (acid rain), sunlight, and the like, and the appearance of the coating film is deteriorated.

  Further, in recent years, metallic appearances coated with a coating composition in which a certain amount or more of metallic pigments such as aluminum flakes are applied are particularly preferred in designs such as buildings, but metallic coating films containing metallic pigments. Is coated on the outermost surface, it is known that deterioration of the metallic coating due to corrosion of the metallic pigment or the like (weather resistance deterioration) is likely to occur.

  Therefore, the painting method of applying a clear paint on a metallic coating is a common technique for improving the weather resistance, mainly for the coating of automobile outer panels. A new paint coating facility must be added. In addition, since the number of processes and paints increase, it is difficult to use as a coating method for outdoor base materials from an economical viewpoint.

Various coating compositions for improving the weather resistance of metallic coating films have been studied so far, but many of the coating compositions with excellent weather resistance are inferior to the stain resistance and workability of the coating film. It was difficult to achieve both contamination resistance, weather resistance and processability. (The workability mentioned here means that when a coated metal plate coated with paint is processed, there is little damage to the coating film in processes such as bending, drawing and cutting.)
For example, Patent Document 1 includes two types of polyester resins that define a hydroxyl value, an acid value, and a number average molecular weight, a specific acrylic resin, and a blocked polyisocyanate compound. The topcoat coating composition for precoat is described, and it is disclosed that the topcoat film coated with the coating composition is excellent in workability and stain resistance. Furthermore, although it is also described in the specification that a metallic pigment such as aluminum can be contained in the coating composition, a coating composition containing a certain amount or more of the metallic pigment is not assumed, and due to corrosion of the metallic pigment. There was the fault that the weather resistance of a coating film will fall. Patent Document 2 discloses a composite composition of aluminum flakes, hindered amine light stabilizers and dehydrating agents added to a coating composition based on polyester, acrylic, silicone polyester and / or urethane resins. A metallic paint excellent in weather resistance and color stability, and a metallic pre-coated metal plate coated with the metallic paint are disclosed. However, although the color stability of the metallic paint and the weather resistance and workability of the coating film are excellent, the precoat metal plate has insufficient stain resistance.

JP 2008-201842 A JP 2007-217548 A

  The present invention is a contamination-resistant metallic paint composition capable of forming a coating film excellent in stain resistance and weatherability retention against rainwater, etc., and in particular, stain resistance suitable for forming a top coat film on a coated metal plate having excellent workability. It is to provide a metallic coating composition.

  As a result of intensive studies to solve the above-described conventional problems, the present inventors have developed a specific organosilicate component in a resin binder containing a polyester resin component containing a specific fatty acid-modified polyester resin and a crosslinking component. And / or a coating composition containing a surfactant component and a metallic pigment component has been found to be capable of forming a metallic coating having excellent stain resistance, weather resistance and processability against rainwater, etc. It came to be completed.

That is, this invention provides the following coating composition, the coating-film formation method using this coating composition, and the coating metal plate painted by this coating-film formation method.

1. The total content of the alicyclic polybasic acid (a1-1) obtained by the reaction of the polybasic acid component (a1), the alcohol component (a2) and the fatty acid (a3) and the polybasic acid component (a1) is A fatty acid-modified polyester resin having a number average molecular weight of 4000 to 25000, a hydroxyl value of 5 to 100 mgKOH / g, and an oil length of 3 to 35% in a range of 50 to 100 mol% based on the total amount of the polybasic acid component (a1) Polyester resin component (A) containing 50 to 100% by mass of (A1), Crosslinker component (B) containing 50 to 100% by mass of butyl etherified melamine resin (B1), general formula: (R1) n-Si- (OR2) 4-n (wherein R1 is an alkyl or phenyl group having 1 to 18 carbon atoms which may be substituted with an epoxy group or a mercapto group, and R2 is an alkyl having 1 to 6 carbon atoms) A coating composition containing an organosilicate component (C) and / or a surfactant component (D) having the following characteristics, and a metallic pigment component (E): And based on the total solid content of component (A) and component (B),
(A) Content of a component is 50-95 mass%,
(B) Content of a component is 5-50 mass%,
Content of (C) component and / or (D) component is 0.1-20 mass%,
(E) Content of component is 10 to 60% by mass
A contamination-resistant metallic paint composition characterized by
Surfactant component (D): anionic surfactant having at least one nonionic surfactant (D-1) selected from polyethylene glycol fatty acid ester, sorbitan fatty acid ester and glycerin fatty acid ester and / or sulfosuccinate group (D-2).
2. The content of 1,2-cyclohexanedicarboxylic acid and / or 1,2-cyclohexanedicarboxylic anhydride in the polybasic acid component (a1) is 50 to 100 mol based on the total amount of the polybasic acid component (a1). 2. The contamination-resistant metallic paint composition according to item 1, wherein the composition is in the range of%.
3. Item 3. The resistance according to Item 1 or 2, wherein the content of neopentyl glycol in the alcohol component (a2) is in the range of 25 to 100 mol% based on the total amount of the alcohol component (a2). Contaminated metallic paint composition.
4). An amino group or a quaternary ammonium base-containing polymerizable unsaturated monomer, a polymerizable unsaturated monomer having a nitrogen atom-containing heterocyclic ring, and N-substituted may be substituted (meth) with respect to the total amount of all the constituent monomers. A copolymer resin (F) comprising at least one polymerizable unsaturated monomer 20 to 70% by mass selected from acrylamide compounds and other polymerizable unsaturated monomer 30 to 80% by mass as a constituent component (A) The contamination-resistant metallic coating composition according to any one of Items 1 to 3, which is contained in an amount of 0.1 to 20% by mass based on the total amount of the solids of the component and the component (B).
5. 5. The contamination-resistant metallic material according to any one of the above items 1 to 4, wherein the metallic pigment component (E) is an aluminum pigment, and the average particle size of the aluminum pigment is in the range of 5 to 33 μm. Paint composition.
6). 6. The antifouling metallic paint composition, wherein the aluminum pigment according to item 5 is a resin-coated aluminum pigment.
7). 7. A contamination-resistant metallic coating composition, wherein the cured coating film obtained by heat-curing the coating composition according to any one of items 1 to 6 has a glass transition temperature of 30 to 100 ° C.
8). Item 8. The coating composition according to any one of Items 1 to 7, wherein the coating composition contains a matting agent, and a cured coating film obtained by heat-curing the coating composition has a 60 ° gloss value of less than 60%. Contamination resistant metallic paint composition.
9. The light transmittance of the cured coating film coated with the coating composition according to any one of the above items 1 to 8 at a film thickness of 15 μm and heat-cured is an average of 5% or less at a wavelength of 310 to 350 nm. A feature of a stain resistant metallic coating composition.
10. A primer coating film is formed on a metal plate, and the antifouling metallic coating composition according to any one of the above items 1 to 9 is applied onto the primer coating film so as to be overcoated with a film thickness of 5 to 50 μm. A method of forming a coating film, comprising forming a film.
11. Item 11. The method for forming a coating film according to Item 10, wherein the primer coating is a chromium-free primer coating that does not contain a chromium-based anticorrosive component.
12 The primer paint comprises (I) a bisphenol type epoxy resin modified with a soft organic component obtained by reacting 5 to 50% by mass of a soft organic component and 95 to 50% by mass of a bisphenol type epoxy resin, (II) a curing agent, and (III) A coating composition containing a rust preventive pigment, wherein the soft organic component in the resin (I) is an aliphatic polybasic acid having 4 to 36 carbon atoms and an acrylic resin having a glass transition temperature of -20 to 50 ° C Item 12. The method for forming a coating film according to Item 10 or 11, wherein the primer coating composition is at least one of a resin and a polyester resin having a glass transition temperature of -20 to 50 ° C.
13. A coated metal sheet having a multilayer coating film formed by the coating film forming method according to any one of Items 10 to 12.

  The contamination-resistant metallic coating composition of the present invention comprises a polyester resin component (A), a crosslinking agent component (B), an organosilicate component (C) and / or a surfactant component (D), and a metallic pigment component (E). It is a coating composition to be contained, and with this coating composition, it is possible to form a coating film excellent in stain resistance retention, weather resistance and workability with respect to rainwater or the like, particularly in a metallic coating film.

  Further, the specific fatty acid-modified polyester resin which is an essential component has good weather resistance and hydrolysis resistance because 50 mol% or more of the polybasic acid component is an alicyclic polybasic acid. In addition, the fatty acid-modified portion is usually improved in adsorption to the metallic pigment used in the antifouling metallic paint composition, and the sedimentation stability in the paint and the weather resistance of the coating film are improved.

  The reason why the metallic coating film by the contamination-resistant metallic coating composition of the present invention can form a coating film excellent in retention of stain resistance against rainwater and the like, and excellent in weather resistance and workability is not clear. However, I think as follows.

  The coating composition of the present invention contains an organosilicate component and / or a surfactant component as a stain resistance imparting component. The organosilicate component exhibits high hydrophilicity on the coating film surface by hydrolysis. As a result, it is possible to suppress the adhesion of oily contaminants and to wash the adhered contaminants with water droplets such as rain. In addition, the surfactant component is considered to have a stain resistance effect because it is difficult for the contaminants to adhere to the coating surface due to the antistatic effect.

  However, the stain-resistant coating film has a drawback that the coating film surface is easily deteriorated because the coating film surface is hydrophilic. Furthermore, metallic coatings and / or matting coatings containing metallic pigments have surface irregularities due to large particle size pigments, so water wettability is good, and the hydrolysis resistance of the polyester resin as the base resin is good. With regard to the above, since it is exposed to a more severe situation, when a general polyester paint system considering only conventional processability is used, deterioration of the coating surface (choking, etc.) is accelerated and it tends to be an unsightly appearance.

  Therefore, the metallic coating obtained by the contamination-resistant metallic coating composition of the present invention is excellent in weather resistance and hydrolysis resistance due to the fatty acid-modified polyester resin that uses a large amount of alicyclic polybasic acid, and adsorbs fatty acid-modified portions. The deterioration of the metallic pigment is also suppressed by the above, and further, by containing a stain resistance imparting component (organosilicate component and / or surfactant component), it is excellent while maintaining high processability as compared with the conventional polyester paint system. It is considered that the stain resistance and weatherability can be exhibited.

  The contamination-resistant metallic coating composition of the present invention comprises the following polyester resin component (A), crosslinking agent component (B), organosilicate component (C) and / or surfactant component (D), and metallic pigment component (E ) Containing a coating composition.

Polyester resin component (A)
In the coating composition of the present invention, the polyester resin component (A) contains 50 to 100% by mass of the following fatty acid-modified polyester resin (A1).

Fatty acid-modified polyester resin (A1)
The fatty acid-modified polyester resin (A1) that is an essential component of the polyester resin component (A) is obtained by a reaction of the following polybasic acid component (a1), alcohol component (a2), and fatty acid (a3).

Polybasic acid component (a1)
In this invention, it is preferable to contain an alicyclic polybasic acid (a1-1) as a polybasic acid component (a1). The content of the alicyclic polybasic acid (a1-1) is in the range of 50 to 100 mol%, further 60 to 100 mol%, more particularly 70 to 100 mol%, based on the total amount of the polybasic acid component (a1). It is preferable to be within.

  The alicyclic polybasic acid (a1-1) is generally a compound having one or more alicyclic structures (mainly 4 to 6 membered rings) and two or more carboxyl groups in one molecule, Acid anhydrides and esterified products of the compounds, for example, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, Cycloaliphatic polyvalents such as 3-methyl-1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,3,5-cyclohexanetricarboxylic acid, etc. Carboxylic acid; anhydride of the alicyclic polyvalent carboxylic acid; lower alkyl esterified product of the alicyclic polyvalent carboxylic acid, and the like. Rhohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic anhydride, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, 4-cyclohexene-1,2- Dicarboxylic acid anhydride can be preferably used. The said alicyclic polybasic acid (a1-1) can be used individually by 1 type or in combination of 2 or more types.

  Among the above, from the viewpoint of hydrolysis resistance, 1,2-cyclohexanedicarboxylic acid and / or 1,2-cyclohexanedicarboxylic anhydride is particularly preferable, and the content in both polybasic acid components (a1) is as follows. Based on the total amount of the polybasic acid component (a1), it is preferably in the range of 50 to 100 mol%, further 60 to 100 mol%, more particularly 70 to 100 mol%.

  As the polybasic acid component, an aromatic polybasic acid (a1-2) and an aliphatic polybasic acid (a1-3) can be used in addition to the alicyclic polybasic acid (a1-1).

The aromatic polybasic acid (a1-2) is generally an aromatic compound having two or more carboxyl groups in one molecule, an acid anhydride of the aromatic compound, and an esterified product of the aromatic compound. For example, aromatic polyvalent carboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, trimellitic acid, pyromellitic acid; anhydride of the aromatic polyvalent carboxylic acid A lower alkyl esterified product of the aromatic polyvalent carboxylic acid. The said aromatic polybasic acid (a1-2) can be used individually by 1 type or in combination of 2 or more types.
Moreover, it is preferable not to use a phthalic acid, an isophthalic acid, and a terephthalic acid among viewpoints from viewpoints, such as a weather resistance.

  The aliphatic polybasic acid (a1-3) is generally an aliphatic compound having two or more carboxyl groups in one molecule, an acid anhydride of the aliphatic compound, and an esterified product of the aliphatic compound. Aliphatic polycarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid, octadecanedioic acid, citric acid; An anhydride of the aliphatic polyvalent carboxylic acid; a lower alkyl esterified product of the aliphatic polyvalent carboxylic acid, and the like. The said aliphatic polybasic acid can be used individually by 1 type or in combination of 2 or more types.

  As said aliphatic polybasic acid (a1-3), it is preferable to use the dicarboxylic acid which has a C4-C18 alkyl chain. Examples of the dicarboxylic acid having an alkyl chain having 4 to 18 carbon atoms include adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassic acid, and octadecanedioic acid. Among them, adipic acid can be preferably used.

Alcohol component (a2)
As the alcohol component (a2), a polyhydric alcohol having two or more hydroxyl groups can be suitably used. Examples of the polyhydric alcohol include dihydric alcohol (a2-1) and trihydric or higher polyhydric alcohol (a2-2).

  Examples of the dihydric alcohol (a2-1) include ethylene glycol, propylene glycol, diethylene glycol, trimethylene glycol, tetraethylene glycol, triethylene glycol, dipropylene glycol, 1,4-butanediol, and 1,3-butanediol. 2,3-butanediol, 1,2-butanediol, 3-methyl-1,2-butanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,2-pentanediol, 1, 5-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 2,3-dimethyltrimethylene glycol, tetramethylene glycol, 3-methyl-4,3-pentanediol, 3-methyl-1,5 -Pentanediol, 2,2,4-trimethyl-1,3- Nthanediol, 1,6-hexanediol, 1,5-hexanediol, 1,4-hexanediol, 2,5-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, tricyclodecane dimethanol, water Dihydric alcohols such as hydrogenated bisphenol A and hydrogenated bisphenol F; polylactone diols obtained by adding lactones such as ε-caprolactone to these dihydric alcohols; ester diols such as bis (hydroxyethyl) terephthalate; alkylene of bisphenol A Examples include oxide adducts, polyether diols such as polyethylene glycol, polypropylene glycol, and polybutylene glycol. The above dihydric alcohols can be used alone or in combination of two or more.

  Among the above, it is particularly preferable to use neopentyl glycol as a part of the alcohol component (a2). The content of the neopentyl glycol is 20 to 100 mol% based on the total amount of the alcohol component (a2). Further, it is preferable to be in the range of 25 to 90 mol%, more particularly 30 to 80 mol%.

  As the alcohol component, in addition to the dihydric alcohol (a2-1), a trihydric or higher polyhydric alcohol (a2-2) and a monoalcohol (a2-3) can be used.

  Examples of the trihydric or higher polyhydric alcohol (a2-2) include glycerin, trimethylolethane, trimethylolpropane, diglycerin, triglycerin, 1,2,6-hexanetriol, pentaerythritol, dipentaerythritol, Trihydric or higher alcohols such as sorbitol and mannitol; polylactone polyols obtained by adding lactones such as ε-caprolactone to these trihydric or higher alcohols; tris (2-hydroxyethyl) isocyanurate, tris (2- And tris (hydroxyalkyl) isocyanurate such as hydroxypropyl) isocyanurate and tris (2-hydroxybutyl) isocyanurate. The trihydric or higher polyhydric alcohols can be used singly or in combination of two or more.

  Among these, trimethylolpropane is particularly preferable from the viewpoint of increasing the molecular weight and improving the reactivity with the fatty acid (a3), and the content of the trimethylolpropane is based on the total amount of the alcohol component (a2). It is preferable to be within the range of 20 to 100 mol%, further 25 to 90 mol%, more particularly 30 to 80 mol%.

  Examples of the monoalcohol (a2-3) include monoalcohols such as methanol, ethanol, propyl alcohol, butyl alcohol, stearyl alcohol, and 2-phenoxyethanol; glycidyl esters of propylene oxide, butylene oxide, and synthetic highly branched saturated fatty acids (trade names) Examples thereof include alcohol compounds obtained by reacting a monoepoxy compound such as “Cardura E10” (made by HEXION Specialty Chemicals) with an acid. The said monoalcohol can be used individually by 1 type or in combination of 2 or more types.

Fatty acid (a3)
In the present invention, the fatty acid (a3) is a linear hydrocarbon monovalent carboxylic acid, such as coconut oil fatty acid, cottonseed oil fatty acid, hemp seed oil fatty acid, rice bran oil fatty acid, fish oil fatty acid, tall oil fatty acid, soybean oil fatty acid. Fatty acids such as linseed oil fatty acid, tung oil fatty acid, rapeseed oil fatty acid, castor oil fatty acid, dehydrated castor oil fatty acid, safflower oil fatty acid; lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, etc. Can be mentioned. The said fatty acid can be used individually by 1 type or in combination of 2 or more types.

  Of these, those having a low degree of unsaturation, specifically those having an iodine value of 20 or less, particularly 10 or less, are preferred from the viewpoint of weather resistance. The iodine value is a numerical value serving as an index representing the degree of unsaturation of the compound, and is represented by the number of g of iodine absorbed by 100 g of the sample. The measurement can be performed according to the standard of JIS K 5421.

  From the viewpoint of the degree of unsaturation, the fatty acid (a3) is preferably coconut oil fatty acid, lauric acid, myristic acid, palmitic acid, or stearic acid, and particularly preferably coconut oil fatty acid.

  The production of the fatty acid-modified polyester resin (A1) is not particularly limited, and can be performed according to a usual method. For example, the polybasic acid component (a1), the alcohol component (a2), and the fatty acid (a3) are reacted at 150 to 250 ° C. for 5 to 10 hours in a nitrogen stream to perform an esterification reaction or a transesterification reaction. A method is mentioned.

  The modification with the fatty acid (a3) is performed simultaneously with the esterification reaction or transesterification reaction of the polybasic acid component (a1) and the alcohol component (a2), or after the esterification reaction or after the transesterification reaction. Can do.

  The polybasic acid component (a1), alcohol component (a2), and fatty acid (a3) may be added at once, or may be added in several portions. Moreover, after synthesize | combining a carboxyl group-containing fatty acid modified polyester resin first, you may esterify this carboxyl group-containing fatty acid modified polyester resin using the said alcohol component (a2). Furthermore, after first synthesizing a hydroxyl group-containing fatty acid-modified polyester resin, the acid anhydride may be reacted to half-esterify the hydroxyl group-containing fatty acid-modified polyester resin.

  In the esterification or transesterification reaction, a catalyst may be used to promote the reaction. As the catalyst, known catalysts such as dibutyltin oxide, antimony trioxide, zinc acetate, manganese acetate, cobalt acetate, calcium acetate, lead acetate, tetrabutyl titanate, and tetraisopropyl titanate can be used.

  Further, the fatty acid-modified polyester resin (A1) can be modified with a monoepoxy compound during the preparation of the resin or after the preparation. As the monoepoxy compound, for example, a glycidyl ester of a synthetic highly branched saturated fatty acid (trade name “Cardura E10” manufactured by HEXION Specialty Chemicals) can be suitably used.

  The fatty acid-modified polyester resin (A1) preferably has a number average molecular weight within the range of 4,000 to 250,000, more preferably 5,000 to 22,000, and even more preferably 6,000 to 20,000, from the viewpoint of processability and smoothness of the resulting coating film.

  In addition, the fatty acid-modified polyester resin (A1) generally has a hydroxyl value in the range of 5 to 100 mgKOH / g, more preferably 10 to 90 mgKOH / g, more particularly 40 to 80 mgKOH / g, from the viewpoint of curability of the resulting coating film. It is preferable to have.

  The fatty acid-modified polyester resin (A1) preferably has an oil length in the range of 3 to 35%, further 5 to 30%, more particularly 5 to 25%, from the viewpoint of the weather resistance of the resulting coating film. . Here, the oil length is mass% of the fatty acid component (a3) with respect to the total amount of the acid component (a1), the alcohol component (a2) and the fatty acid component (a3) which are constituent components.

  In addition, the fatty acid-modified polyester resin (A1) preferably has a glass transition temperature in the range of 0 to 50 ° C., more preferably 10 to 40 ° C., from the viewpoint of the hardness and workability of the obtained coating film.

  The adjustment of the number average molecular weight and the hydroxyl value of the fatty acid-modified polyester resin (A1) is, for example, equivalent of the carboxyl group in the polybasic acid component (a1) and the fatty acid component (a3) and the hydroxyl group in the alcohol component (a2). The ratio (COOH / OH) can be adjusted, or the reaction time in the esterification reaction or transesterification reaction can be adjusted.

  In addition, the equivalent ratio (COOH / OH) of the carboxyl group in the polybasic acid component (a1) to the hydroxyl group in the alcohol component (a2) is generally 0.5 to 0.98, more preferably 0.6 to 0. It is preferable to be within the range of .95.

  In addition, the number average molecular weight and the weight average molecular weight in this specification are based on the number average molecular weight and the weight average molecular weight measured with a gel permeation chromatograph (manufactured by Tosoh Corporation, “HLC8120GPC”) based on the molecular weight of standard polystyrene. It is a converted value. In this measurement, four columns of “TSKgel G-4000HXL”, “TSKgel G-3000HXL”, “TSKgel G-2500HXL”, and “TSKgel G-2000HXL” (both trade names, manufactured by Tosoh Corporation) were used as columns. The measurement conditions of mobile phase tetrahydrofuran, measurement temperature 40 ° C., flow rate 1 mL / min, detector RI were used.

  Moreover, in this specification, the glass transition temperature (Tg) of resin is based on a differential thermal analysis (DSC).

As the polyester resin component (A), in addition to the fatty acid-modified polyester resin (A1), a normal fatty acid-modified oil-free polyester resin (A2) and / or a fatty acid-modified product having an oil length of less than 3% by the fatty acid component (a3) Polyester resins can be used.
The oil-free polyester resin (A2) is a polyester resin that does not contain a fatty acid obtained by esterification or transesterification of the polybasic acid component (a1) and the alcohol component (a2) by a conventional method. (A1) and the alcohol component (a2) can be produced in the same manner as in the fatty acid-modified polyester resin (A1), using those exemplified in the fatty acid-modified polyester resin (A1). it can.

  In the present invention, the amount of the fatty acid-modified polyester resin (A1) is 50 to 100% by mass with respect to the total amount of the polyester resin component (A), from the viewpoint of weather resistance and corrosion resistance retention of the resulting coating film, It is preferable to be within the range of 60 to 100% by mass, more particularly 70 to 100% by mass. The amount of the oil-free polyester resin (A2) is in the range of 0 to 50% by mass, further 0 to 40% by mass, more particularly 0 to 30% by mass with respect to the total amount of the polyester resin component (A). Is preferred.

Crosslinker component (B)
In the coating composition of the present invention, the crosslinking agent component (B) contains 50 to 100% by mass of the following butyl etherified melamine resin (B1) based on the total solid content of the crosslinking agent component (B). is there. The crosslinking agent component (B) is a melamine resin (B2) and / or polyisocyanate compound (B3) other than the butyl etherified melamine resin (B1), based on the total solid content of the crosslinking agent component (B). 0.1-50 mass%. Furthermore, it can be contained within a range of 0.1 to 30% by mass, more particularly 0.1 to 20% by mass.

Butyl etherified melamine resin (B1)
The butyl etherified melamine resin is a part of the methylol group in the methylolated melamine resin, which is an addition reaction product of melamine and aldehyde components such as formaldehyde and paraformaldehyde (which may be either a monomer or a multimer). Alternatively, it is a melamine resin that is etherified with n-butyl alcohol or isobutyl alcohol, and has a number average molecular weight of 800 to 8000, particularly 1000 to 5000, in terms of the processability and stain resistance of the resulting coating film. It is preferable to be in the range. The butyl etherified melamine resin (B1) can be used alone or as a mixture of two or more.

  Commercially available products of butyl etherified melamine resin (B1) include, for example, Uban 20SE, 225 (all of which are manufactured by Mitsui Chemicals, Inc.), Super Becamine J820-60, L-117-60, L- 109-65, 47-508-60, L-118-60, G821-60 (all are manufactured by DIC Corporation).

  As the crosslinking agent component (B), in addition to the butyl etherified melamine resin, a melamine resin (B2) other than the butyl etherified melamine resin can be used.

  Examples of the melamine resin (B2) other than the butyl etherified melamine resin include addition reaction products of melamine and aldehyde components such as formaldehyde and paraformaldehyde (which may be either a monomer or a multimer). A melamine resin obtained by etherifying some or all of the methylol groups in the methylolated melamine resin with one or more alcohols other than n-butyl alcohol or isobutyl alcohol can be given. Examples of alcohols used for etherification include monohydric alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, 2-ethylbutanol, and 2-ethylhexanol.

  Examples of the melamine resin etherified with methyl alcohol include Sumimar M-100, M-40S, and M-55 (all trade names, manufactured by Sumitomo Chemical Co., Ltd.), Cymel 300, 303, 325, and 327. 350, 370, 730, 736, 736 (above, both are made by Mitsui Cytec Co., Ltd., trade name), Melan 522, 523 [above, both are made by Hitachi Chemical Co., Ltd.], Nicarak MS17, Methyl etherified melamines such as MS15, MS001, MX430, MX650 (all manufactured by Sanwa Chemical Co., Ltd., trade names), Resimin 740, 741 and 747 (all of which are manufactured by Monsanto Co., Ltd.) Resins can be mentioned.

  Examples of melamine resins etherified with methyl alcohol and butyl alcohol include Cymel 232, 235, 202, 238, 254, 266, 272, 1130, XV-514, XV805 (both Examples include methyl / butyl mixed etherified melamine resins such as Nippon Cytec Industries, Ltd. (trade name), Sumimar M66B (trade name, Sumitomo Chemical Co., Ltd.), Resimin 753, 755 (all of which are manufactured by Monsanto). be able to.

  In the present invention, the amount of the butyl etherified melamine resin (B1) is 50 to 100% by mass with respect to the total amount of the crosslinking agent component (B) from the viewpoint of the workability of the resulting coating film and the stain resistance retention. Furthermore, it is preferable that it is in the range of 70 to 100% by mass, more particularly 80 to 100% by mass.

  Moreover, in order to accelerate | stimulate hardening reaction with a polyester resin component (A) and a crosslinking agent component (B), a curing catalyst can be used as needed. As a curing catalyst for promoting this curing reaction, a sulfonic acid compound or a neutralized product of a sulfonic acid compound is generally used.

  Examples of the sulfonic acid compound include p-toluenesulfonic acid, dodecylbenzenesulfonic acid, dinonylnaphthalenesulfonic acid, dinonylnaphthalenedisulfonic acid, and the like. Examples of the neutralizing agent in the neutralized product of the sulfonic acid compound include basic compounds such as primary amine, secondary amine, tertiary amine, ammonia, caustic soda, and caustic potash.

Polyisocyanate compound (B3)
As a crosslinking agent component (B), a polyisocyanate compound (B3) can be contained. The polyisocyanate compound (B3) is a compound having two or more isocyanate groups in one molecule, and examples thereof include aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; hydrogenated xylylene diisocyanate and isophorone diisocyanate. Cycloaliphatic diisocyanates such as tolylene diisocyanate, aromatic diisocyanates such as 4,4′-diphenylmethane diisocyanate; triphenylmethane-4,4 ′, 4 ″ -triisocyanate, 1,3,5-triisocyanatobenzene , 2,4,6-triisocyanatotoluene, 4,4'-dimethyldiphenylmethane-2,2 ', 5,5'-tetraisocyanate and other polyisocyanates having three or more isocyanate groups Organic polyisocyanate itself such as a compound, or an adduct of each of these organic polyisocyanates and a polyhydric alcohol, a low molecular weight polyester resin or water, or the above-mentioned cyclized polymer of each organic polyisocyanate, Examples thereof include isocyanate and biuret compounds, etc. Among these, isocyanurate obtained by cyclopolymerization of hexamethylene diisocyanate can be preferably used.

  Moreover, a block polyisocyanate compound can also be used as a polyisocyanate compound.

  The blocked polyisocyanate compound is a compound obtained by blocking free isocyanate groups of a polyisocyanate compound with a blocking agent.

  Examples of the blocking agent include phenols such as phenol, cresol and xylenol; ε-caprolactam; lactones such as δ-valerolactam and γ-butyrolactam; methanol, ethanol, n-, i- or t-butyl alcohol, ethylene Alcohols such as glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, and benzyl alcohol; oximes such as formamidoxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, diacetyl monooxime, benzophenone oxime, cyclohexane oxime System: dimethyl malonate, diethyl malonate, diisopropyl malonate, ethyl acetoacetate, acetyl acetate The blocking agent such as active methylene, such as tons can be suitably used. By mixing the polyisocyanate compound and the blocking agent, free isocyanate groups of the polyisocyanate compound can be easily blocked.

  The polyisocyanate compound and the block polyisocyanate compound can be used singly or in combination of two or more.

  A curing catalyst can also be used to improve the curability of the polyisocyanate compound and the block polyisocyanate compound. Examples of the curing catalyst include tin octylate, dibutyltin di (2-ethylhexanoate), dioctyltin di (2-ethylhexanoate), dibutyltin dilaurate, dibutyltin oxide, dioctyltin oxide, and 2-ethyl. An organometallic catalyst such as lead hexanoate can be suitably used.

  In the antifouling metallic coating composition of the present invention, the ratio of the polyester resin component (A) and the crosslinking agent component (B) is based on the total solid content of the polyester resin component (A) and the crosslinking agent component (B). The polyester resin component (A) is 50 to 95% by mass, further 60 to 80% by mass, and the crosslinking agent component (B) is 5 to 50% by mass and further 10 to 40% by mass. From the viewpoints of curability, stain resistance, mechanical strength, workability, solvent resistance, corrosion resistance, weather resistance, and the like.

Organosilicate component (C)
The organosilicate component (C) of the present invention has a general formula: (R ¹ ) _n —Si— (OR ² ) _{4 -n} (wherein R ¹ is carbon number optionally substituted with an epoxy group or a mercapto group) 1 to 18 alkyl group or phenyl group, R ² is an alkyl group having 1 to 6 carbon atoms, and n is 0 or 1.), a condensate of the organosilicate Is also included in component (C).

  The component (C) used in the coating composition of the present invention is blended in order to efficiently exhibit a hydrophilic effect on the substrate surface after coating. From the viewpoint of this effect, the condensation of the above-described organosilicate. More preferred.

Specific examples of R ¹ in the above general formula include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, n-octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, Examples include tetradecyl, hexadecyl, octadecyl, glycidyl, methylglycidyl, mercaptomethyl, 2-mercaptoethyl, 2-mercaptopropyl, 3-mercaptopropyl, 4-mercaptobutyl, phenyl, and p-mercaptophenyl groups.

  Specific examples of the organosilicate of component (C) include tetrafunctional silanes such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraisobutoxysilane; methyltrimethoxysilane, methyl Triethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, methyltri-n-butoxysilane, methyltriisobutoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, phenyltriisopropoxysilane, phenyltri n-butoxysilane, phenyltriisobutoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, lauryltrimethoxysilane, lauryltrieth Shishiran, mercaptomethyl trimethoxysilane, mercaptoethyl trimethoxy silane, mercaptomethyl triethoxysilane, mercaptopropyl triethoxysilane, mercaptopropyl trimethoxysilane, include trifunctional silanes such as mercaptopropyltriethoxysilane. Examples of the condensate of the organosilicate include a condensate of one of these tetrafunctional or trifunctional silanes or a combination of two or more thereof.

  The organosilicate condensate can be produced by a conventional method. Examples of commercially available products include MKC silicate MS51, MS56, MS57, MS56S, MS56SB5, MS58B15, MS58B30, ES40, EMS31, and BTS (all of which are Mitsubishi. Chemical Co., Ltd., trade name), methyl silicate 51, ethyl silicate 40, ethyl silicate 40T, ethyl silicate 48 (all are trade names, manufactured by Colcoat Co., Ltd.), KR500, KR9218, X-41-1805, X-41-1810, X-41-1818, X-41-1053, X-41-1056 (all are trade names manufactured by Shin-Etsu Chemical Co., Ltd.) and the like. Further, these organosilicate condensates can be obtained by single hydrolysis or by partial hydrolysis condensation using a combination of two or more. The organosilicate condensate is a branched or linear condensate, preferably having a condensation degree of 2 to 100, more preferably 2 to 20. In the coating composition of the present invention, the organosilicate or organosilicate condensate of component (C) may be used alone or in combination of two or more.

In the organosilicate represented by the above general formula and / or its condensate, it has a methoxy group and an alkoxy group having 2 to 6 carbon atoms as an OR ² group, and a methoxy group / an alkoxy group having 2 to 6 carbon atoms; It is preferable from the viewpoint of the pot life after the preparation of the paint that the ratio of the number is in the range of 95/5 to 30/70.

  In the coating composition of the present invention, the content of the component (C) is 0.1 to 20% by mass, and further 0.5 to 15 based on the total solid content of the component (A) and the component (B). It is preferable that the content is 1% by mass, more particularly 1 to 10% by mass. (C) When the amount of component is in the above range, the effect of blending component (C) is exhibited, and the initial stain resistance of the coating film, retention of stain resistance, mechanical strength of the coating film, durability It is also preferable from the aspect.

Surfactant component (D)
In the coating composition of the present invention, the surfactant component (D) is at least one nonionic surfactant (D-1) selected from polyethylene glycol fatty acid ester, sorbitan fatty acid ester, and glycerin fatty acid ester, and / or sulfosuccinate. It is characterized by containing an anionic surfactant (D-2) characterized by containing an anionic surfactant (D-2-1) having an acid base.

  In the nonionic surfactant used in the coating composition of the present invention, the nonionic property is a property in which neither a k part nor an anionic part can be formed in the molecular structure in water. The ionicity expressed as means the property that a cation moiety or an anion moiety can exist in the molecular structure in water.

  The surfactant usually has an antistatic effect, and this antistatic effect can suppress the charging of the obtained coating film, and the nonionic surfactant uses an ionic surfactant. Compared to the case, it is possible to obtain a coating film having excellent resistance involving water load such as water resistance.

Nonionic surfactant component (D-1)
As a nonionic surfactant (D-1) that can be used in the coating composition of the present invention, for example,
Polyethylene glycol fatty acid esters such as POE monolaurate, POE dilaurate, POE monooleate, POE dioleate, POE monostearate, POE distearate, ethylene glycol distearate,
Sorbitan monooleate, sorbitan monostearate, sorbitan dioleate, sorbitan distearate, sorbitan tetraoleate, sorbitan caprylate, POE sorbitan monooleate, POE sorbitan monostearate, POE sorbitan distearate, POE sorbitan mono Sorbitan fatty acid esters such as myristylate, POE sorbitan dimyristate, POE sorbitan dioleate, POE sorbitan tetraoleate,
Sorbit fatty acid esters such as sorbite monolaurate, sorbite monooleate, sorbite pentaoleate, sorbite monostearate, POE sorbite monolaurate, POE sorbite monooleate, POE sorbite pentaoleate, POE sorbite monostearate,
Glycerol monomyristate, glycerol monostearate, glycerol monoisostearate, glycerol monooleate, glycerol distearate, glycerol diisostearate, polyglycerol monomyristate, diglycerol stearate, polyglycerol monostearate , Decaglycerol laurate, polyglycerol monoisostearate, polyglycerol monooleate, polyglycerol distearate, polyglycerol diisostearate, polyglycerol tristearate, polyglycerol pentaoxystearate, polyglycerol hepta stearate , Polyglycerol heptaoleate, POE glycerol monostearate, POE glycerol monooleate, POE glycerol triisostearate, etc. Serine fatty acid ester,
Can give.
These nonionic surfactants (D-1) can be used singly or in combination of two or more.
In the present specification, in the nonionic surfactant, “POE” is an abbreviation of “polyoxyethylene”.
As the nonionic surfactant, those having a melting point of 30 to 60 ° C. can be suitably used from the viewpoint of stain resistance and water resistance.
As the nonionic surfactant, those containing a hydroxyl group can be suitably used from the viewpoint of stain resistance and water resistance.
The number average molecular weight of the nonionic surfactant is preferably from 500 to 3000, particularly preferably from 1000 to 2500, from the viewpoint of stain resistance and appearance of the resulting coating film.

  If the number-average molecular weight of the nonionic surfactant is less than 500, the surfactant is likely to be washed away from the coating film due to the influence of rain water, etc. in the outdoor use environment, and the anti-staining effect is reduced due to the decrease in the antistatic effect. There is a case. Moreover, when it exceeds 3000, the external appearance of the coating film obtained may fall by the compatibility fall with (A) component, (B) component, or (C) component.

The appropriate range of the HLB value of the nonionic surfactant varies depending on the type of organosilicate and the selected nonionic surfactant, but from the viewpoint of stain resistance and various coating film performances, 3-12 In particular, it is preferably within the range of 4 to 10.
When the HLB value is less than 3, the nonionic surfactant is low in hydrophilicity, so that the antistatic effect of the surfactant is insufficient, and thus the stain resistance of the resulting coating film may be lowered.
On the other hand, when the HLB value exceeds 12, the nonionic surfactant has too high hydrophilicity, and thus the water resistance and the like of the resulting coating film may be lowered.

Anionic surfactant (D-2)
Examples of the anionic surfactant (D-2) that can be used in the coating composition of the present invention include various fatty acid salts, higher alcohol sulfates, alkylbenzene sulfonates, polyoxyethylene alkylphenyl ether sulfates, and polycarboxylic acids. Examples thereof include acid type polymer surfactants, and these can be used singly or in combination of two or more. In particular, an anionic surfactant (D-2-1) having a sulfosuccinate group can be preferably used.

Anionic surfactant having a sulfonate group (D-2-1)
Examples of the anionic surfactant (D-2-1) having a sulfosuccinic acid group include monoalkyl sulfosuccinic acid ester salts, dialkyl sulfosuccinic acid ester salts, sulfosuccinic acid alkyl disalts, polyoxyethylene alkyl sulfosuccinic acid disalts, Sodium alkylamine oxide bistridecyl sulfosuccinate, sodium dioctyl sulfosuccinate, sodium dihexyl sulfosuccinate, sodium dicyclohexylsulfosuccinate, sodium diamylsulfosuccinate, sodium diisobutylsulfosuccinate, disodium isodecylsulfosuccinate, disodium N-octadecylsulfosuccinate amide N- (1,2-dicarboxyethyl) -N-octadecylsulfosuccinic acid amide tetrasodium and the like. These anionic surfactants (D-2-1) having a sulfosuccinate group may be used alone or in combination of two or more. Further, the sulfosuccinic acid group referred to here is a state in which a part or all of the sulfosuccinic acid group is converted to a sulfosuccinic acid group by neutralization or the like, and a part of the sulfosuccinic acid group may exist.
Among the anionic surfactants (D-2-1) having the sulfosuccinate group, a dialkyl sulfosuccinate sodium salt having a structural formula represented by the following general formula (I) is particularly preferable for improving the stain resistance. .

(Wherein R ² and R ³ are the same or different and each represents an alkyl group having 1 to 15 carbon atoms)
Commercially available sulfosuccinic acid-based anionic surfactants include “Perex OT-P”, “Perex TR”, “Perex CS” and “Perex TA” manufactured by Kao Corporation; "Call 290-A", "New Call 290-M", "New Call 291-M", "New Call 291-PG", "New Call 291-GL", "New Call 292-PG", "New Call 293 "Neocoal SW-C", "Neocoal YSK", and "Neocoal P" manufactured by Daiichi Kogyo Seiyaku Co., Ltd. may be mentioned.

In the coating composition of the present invention, the content of the surfactant component (D) is 0.1 to 20% by mass based on the total solid content of the component (A) and the component (B), and is further preferably 0.00. 5 to 15% by mass, more particularly 1 to 10% by mass is preferable.
Moreover, also when the coating composition of this invention contains both (C) component and (D) component, 0.1-20 mass%, further 0.5-15 mass%, respectively 1-10 are especially preferable. It is preferable to contain within the range of mass%.

Metallic pigment component (E)
The metallic pigment component (E) used in the coating composition of the present invention is a pigment component that imparts a glittering glittering or light interference pattern to the coating film, and any known pigment component can be used without limitation.

  As the metallic pigment component (E), for example, aluminum, vapor-deposited aluminum, copper, zinc, brass, nickel, aluminum oxide, mica, titanium oxide or iron oxide-coated aluminum oxide, titanium oxide or iron oxide You can list mica. These metallic pigments can be used alone or in combination of two or more.

  The metallic pigment is preferably flake shaped. The average particle diameter of the metallic pigment is preferably about 5 to 33 μm, more preferably about 9 to 30 μm, and particularly preferably about 12 to 26 μm. The average particle size of the metallic pigment can be determined by calculating the volume average from the particle size distribution measured by a known particle size distribution measurement method such as a laser diffraction method, a micromesh sieve method, a Coulter counter method or the like.

  The average thickness of the metallic pigment is not particularly limited, but is preferably in the range of 0.1 to 5 μm, particularly 0.3 to 2.0 μm from the viewpoint of the finished appearance of the coating film.

  As the metallic pigment component (E), an aluminum pigment is particularly preferable. Moreover, as an aluminum pigment, the resin coating aluminum pigment which is excellent in a weather resistance etc. can be used conveniently. The resin-coated aluminum pigment here is an aluminum pigment whose surface is coated with a metal surface of a flake-like aluminum pigment. As a method of coating the metal surface of the aluminum pigment with a resin, a conventionally known surface coating can be used. Specific examples include the methods described in JP-A Nos. 51-137725, 57-35214, and 2002-105381.

  The resin-coated aluminum pigment is excellent in performance such as weather resistance, but is expensive and cannot be contained in a large amount from an economical viewpoint. However, since the coating composition of the present invention is excellent in weather resistance and hydrolysis resistance due to the fatty acid-modified polyester resin using a large amount of alicyclic polybasic acid, it is equivalent to a resin-coated aluminum pigment at a low price even with a normal aluminum pigment. It is possible to obtain the performance of

Moreover, the method of making the coating composition of this invention contain a phosphoric acid group containing acrylic resin, and adsorb | sucking and protecting an aluminum pigment with this phosphoric acid group containing acrylic resin can also be used conveniently. (International Publication WO2002 / 002660)
In the coating composition of the present invention, the content of the metallic pigment component (E) is 10 to 60% by mass, further 12 to 50% by mass, based on the total amount of the solids of the component (A) and the component (B). Further, it is particularly preferably 15 to 40% by mass.

Copolymer resin (F)
When the resin composition of the present invention contains an anionic surfactant (D-2), it is particularly preferable from the viewpoint of stain resistance to contain a copolymer resin component (F) having a nitrogen atom-containing group. . This is because the anionic surfactant (D-2) and the copolymer resin component (F) having a nitrogen atom-containing group interact with each other in the obtained coating film. This is because the anionic surfactant (D-2) can be prevented from flowing out of the coating film due to rain water or the like, and the durability of the stain resistance can be ensured.

  The copolymer resin (F) of the present invention has a nitrogen atom-containing group, specifically, an amino group or a quaternary ammonium base-containing polymerizable unsaturated monomer (f1-1), a nitrogen atom-containing group. At least one polymerizable unsaturated monomer (f1) selected from a polymerizable unsaturated monomer having a heterocyclic ring (f1-2) and an N-substituted (meth) acrylamide compound (f1-3), and It is a copolymer resin (F) obtained by copolymerizing a monomer mixture of another polymerizable unsaturated monomer (f2). Further, the copolymer resin (F) can be used after neutralization.

  Hereinafter, an amino group or quaternary ammonium base-containing polymerizable unsaturated monomer (f1-1), a polymerizable unsaturated monomer having a nitrogen atom-containing heterocyclic ring (f1-2), and N-substituted (meta) ) At least one polymerizable unsaturated monomer (f1) selected from acrylamide compounds (f1-3) may be referred to as “polymerizable unsaturated monomer (f1)”.

  Examples of the amino group or quaternary ammonium base-containing polymerizable unsaturated monomer (f1-1) include aminoethyl (meth) acrylate, Nt-butylaminoethyl (meth) acrylate, N, N-dimethylaminoethyl ( (Meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dipropylaminoethyl (meth) acrylate, N, N-dibutylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) Amino group-containing alkyl (meth) acrylate monomers such as acrylate and N, N-dimethylaminobutyl (meth) acrylate; N, N-dimethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N , N-diethylaminoethyl (meta Amino group-containing (meth) acrylamide monomers such as acrylamide and N, N-dipropylaminoethyl (meth) acrylamide; quaternary ammonium such as methacryloyloxyethyltrimethylammonium chloride (acrylic ester DMC, trade name, manufactured by Mitsubishi Rayon Co., Ltd.) Examples thereof include a base-containing unsaturated monomer.

  Examples of the polymerizable unsaturated monomer (f1-2) having a nitrogen atom-containing heterocyclic ring include (1) vinylpyropidones such as 1-vinyl-2-pyrrolidone and 1-vinyl-3-pyrrolidone, ( 2) For example, vinyl pyridines such as 2-vinyl pyridine, 4-vinyl pyridine, 5-methyl-2-vinyl pyridine, 5-ethyl-2-vinyl pyridine, etc. (3) For example, 1-vinyl imidazole, 1-vinyl Vinylimidazoles such as 2-methylimidazole, (4) vinylquinolines such as 2-vinylquinoline, (5) vinylpiperidines such as 3-vinylpiperidine, N-methyl-3-vinylpiperidine, (6) For example, morpholine of acryloyl morpholine, methacryloyl morpholine, etc. can be mentioned.

  Examples of the (meth) acrylamide compound (f1-3) which may be N-substituted include acrylamide, methacrylamide, N-methylacrylamide, N-methylmethacrylamide, N-methylolacrylamide butyl ether, and N-methylolmethacrylamide. Butyl ether, N-ethylacrylamide, N-ethylmethacrylamide, Nn-propylacrylamide, Nn-propylmethacrylamide, N-isopropylacrylamide, N-isopropylmethacrylamide, N-cyclopropylacrylamide, N-cyclopropylmethacrylate Amides, diacetone acrylamide, diacetone methacrylamide, N-hydroxymethyl acrylamide, N-hydroxymethyl methacrylamide, N-hydroxyethyl Acrylamide, N-hydroxyethylmethacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N, N-diethylacrylamide, N, N-diethylmethacrylamide, N-methyl, N-ethylacrylamide, N- Methyl, N-ethyl methacrylamide, N-methylol acrylamide methyl ether, N-methylol methacrylamide methyl ether, N-methylol acrylamide ethyl ether, N-methylol methacrylamide ethyl ether, N-methylol acrylamide propyl ether, N-methylol methacrylamide Examples thereof include propyl ether, N-methylol acrylamide butyl ether, N-methylol methacrylamide butyl ether and the like. In addition, the N-substituted (meth) acrylamide compound (f1-3) is a monomer having no amino group. These monomers can be used singly or in combination of two or more.

  Examples of other polymerizable unsaturated monomer (f2) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate. C2-C8 hydroxyalkyl ester of acrylic acid or methacrylic acid, monoesterified product of polyhydric alcohol such as polyethylene glycol mono (meth) acrylate and acrylic acid or methacrylic acid, polyether polyol such as polybutylene glycol Monoether of a hydroxyl group-containing polymerizable unsaturated monomer such as 2-hydroxyethyl (meth) acrylate; ε-caprolactone-modified vinyl obtained by ring-opening polymerization of ε-caprolactone to 2-hydroxyethyl (meth) acrylate Nil monomer (for example, “Placcel FA-1”, “Placcel FA-2”, “Placcel FA-3”, “Placcel FA-4”, “Placcel FA-5”, “Placcel FM-1”, “Placcel FM-” Hydroxyl group-containing polymerizable unsaturated monomers such as “2”, “Placcel FM-3”, “Placcel FM-4”, “Placcel FM-5” (all of which are trade names, manufactured by Daicel Chemical Co., Ltd.); , Methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, n -Octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acryl Rate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate “Osaka Organic Chemical Co., Ltd.”, cyclohexyl (meth) acrylate, isobornyl (meth) Acrylic acid esters or methacrylic acid esters which may contain a ring structure having 1 to 24 carbon atoms such as acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, benzyl (meth) acrylate; Aromatic ring-containing vinyl compounds such as styrene, vinyl toluene and α-methylstyrene; vinyl esters such as vinyl propionate and vinyl acetate; nitriles of acrylonitrile and methacrylonitrile; glycidyl (meth) acrylic , 3,4-epoxycyclohexylmethyl (meth) acrylate, vinylcyclohexene monoepoxide, N-glycidyl acrylamide, allyl glycidyl ether and other epoxy group-containing vinyl compounds; acrylic acid, methacrylic acid, maleic acid, fumaric acid, itacone Examples thereof include carboxyl group-containing vinyl compounds such as acids; acid anhydride group-containing vinyl compounds such as maleic anhydride, itaconic anhydride, and hymic anhydride. These can be used individually by 1 type or in combination of 2 or more types.

The blending amount of the polymerizable unsaturated monomer (f1) and the other polymerizable unsaturated monomer (f2) when the copolymer resin (F) is produced is the total monomer component constituting the copolymer resin (F). Polymerizable unsaturated monomer (f1): 20 to 70% by mass, preferably 30 to 65% by mass, other polymerizable unsaturated monomer (f2): 30 to 80% by mass, preferably 35% to the total amount It is desirable for it to exist in the range of 70 mass% for the coating-film performance improvement.
In particular, the copolymer resin (F) preferably contains an amino group or a quaternary ammonium base-containing polymerizable unsaturated monomer (f1-1), and all monomers constituting the copolymer resin (F). The polymerizable group having an amino group or quaternary ammonium base-containing polymerizable unsaturated monomer (f1-1) 1 to 30% by mass, preferably 5 to 25% by mass, and a nitrogen atom-containing heterocyclic ring Saturated monomers (f1-2) 0 to 60% by mass, preferably 10 to 55% by mass, N-substituted (meth) acrylamide compound (f1-3) 0 to 20% by mass, preferably 0 to 15% by mass (“0% by mass” means not blended), and other polymerizable unsaturated monomer (f2) 30 to 80% by mass, preferably 35 to 70% by mass, Antifouling in coatings Sexual Persistence and coating film hardness, it is preferred from the viewpoint of processability.

As a method for obtaining a copolymer resin (F) by copolymerizing a monomer mixture comprising the polymerizable unsaturated monomer (f1) and the other polymerizable unsaturated monomer (f2), a known radical polymerization method can be used. A bulk polymerization method, a solution polymerization method, a bulk-suspension two-stage polymerization method in which suspension polymerization is performed after the bulk polymerization can be preferably used.
In the production of the copolymer resin (F), as the polymerization initiator, a polymerization initiator generally used in a production method of an acrylic polymer or the like is used, and the amount thereof is usually a polymerizable unsaturated monomer (f1). And it is in the range of 0.1-20 mass% with respect to the total amount of other polymerizable unsaturated monomer (f2).

Examples of the polymerization initiator include azo polymerization initiators such as 2,2′-azobisisobutylnitrile, azobis-2-methylbutyronitrile, azobisdivaleronitrile; t-butylperoxyisobutyrate, t -Butylperoxy-2-ethylhexanoate, t-amylperoxy 3,5,5-trimethylhexanoate, t-butylperoxyisopropyl carbonate, 2,2-bis (4,4-di-t-butyl Peroxycyclohexyl) propane and other organic peroxide polymerization initiators.
As a method for obtaining the copolymer resin (F), any known method can be used, and the solution polymerization method is particularly preferable. Examples of the method by the solution polymerization method include a method in which the monomer mixture is dissolved or decomposed in an organic solvent and heated in the presence of a polymerization initiator with stirring at a temperature of usually about 80 ° C to 160 ° C. . The reaction time is usually 1 to 10 hours.

Examples of the organic solvent include hydrocarbon solvents such as heptane, toluene, xylene, octane and mineral spirit; ester solvents such as ethyl acetate, n-butyl acetate, isobutyl acetate, ethylene glycol monomethyl ether acetate, and diethylene glycol monobutyl ether acetate; Ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclohexanone; alcohol solvents such as methanol, ethanol, isopropanol, n-butanol, sec-butanol, isobutanol; n-butyl ether, dioxane, ethylene glycol monomethyl ether, ethylene Ether solvents such as glycol monoethyl ether; SWAZOL 310, SWAZOL 1000, SWAZOL 1500 manufactured by Cosmo Oil Co., Ltd. Aromatic petroleum solvents such as
These organic solvents can be used individually by 1 type or in combination of 2 or more types. At the time of copolymerization, the organic solvent is usually used in an amount of 400% by mass or less based on the total amount of the polymerizable unsaturated monomer (f1) and the other polymerizable unsaturated monomer (f2).

  In the copolymerization reaction for obtaining the copolymer resin (F), the method for adding the monomer component and the polymerization initiator is not particularly limited, but the polymerization initiator is used from the initial stage of polymerization to the late stage of polymerization rather than being charged all at the initial stage of polymerization. It is preferable to divide and drop over the range from the viewpoint of suppressing the formation of defective cross-linked products.

The copolymer resin (F) obtainable by the copolymerization reaction has a weight average molecular weight of 5,000 to 30,000, more preferably 7,000 to 20,000. It is suitable from the viewpoint of easy handling (resin viscosity not very high), coating film hardness, and workability.
A hydroxyl value of 5 to 70 mgKOH / g, preferably 10 to 50 mgKOH / g, is appropriate from the viewpoint of processability. The amine value is 5 to 90 mgKOH / g, preferably 10 to 60 mgKOH / g, from the viewpoint of storage stability.
The blending amount of such copolymer resin (F) is 0.1 to 20 parts by mass, preferably 1 to 15 based on the total solid content of the polyester resin component (A) and the crosslinking agent component (B). A mass part, more preferably 2 to 10 parts by mass, is suitable because a coating film excellent in stain resistance, coating film hardness and workability can be obtained.

Other additives In the coating composition of the present invention , in addition to the components (A), (B), (C), (D), (E) and (F), a hydrolysis accelerator, a coloring pigment, Conventionally used in paints such as extender pigments such as silica fine particles, organic resin powders, inorganic aggregates, pigment dispersants, UV absorbers, UV stabilizers, paint additives such as antifoaming agents and surface conditioners, solvents, etc. Known materials can also be used.

  Examples of the extender pigment include silica fine particles, talc, mica powder, and barita. The amount of the extender pigment is 0.1 to 20% by mass, further 0.5 to 15% by mass, more particularly 1 to 10% by mass, based on the total amount of the solids of the component (A) and the component (B). Preferably there is.

  In addition, the metallic paint composition of the present invention contains a metallic pigment having a relatively large particle size, so that the finished appearance is a matte or semi-glossy coating, but further the gloss adjustment of the resulting coating A matting agent can be used for this purpose. The matting agent is used to lower the gloss of the resulting coating film, and may be either an organic matting agent or an inorganic matting agent, and these may be used alone. Alternatively, two or more types can be used in combination.

  The contamination-resistant metallic coating composition of the present invention can form a coating film particularly excellent in stain resistance retention in a metallic-tone coating film with reduced gloss such as matte or semi-gloss.

  Examples of the organic matting agent include organic resin fine particles that are not completely melted by baking at the time of coating film formation. The organic resin fine particles usually have an average particle diameter of 3 to 80 μm, preferably 5 to 60 μm, from the viewpoint of coating film appearance, coating workability, and the like. Examples of organic matting agents include fluorine resins such as polyvinylidene fluoride and polytetrafluoroethylene, polyamides, acrylic resins, polyurethanes, phenol resins, silicone resins, polypropylene, and polyamides such as nylon 11 and nylon 12. be able to.

  Examples of the inorganic matting agent include silica, mica, alumina, talc, clay, calcium carbonate, barium sulfate and the like.

As a result of adjusting the gloss by adding the matting agent to the coating composition of the present invention, the 60 ° gloss value of the cured coating film obtained by heating and curing the coating composition is within a range of less than 60%. Preferably, it is in the range of 30 to 50%. Actually, it is around 50%. Here, the 60 ° gloss value means that the coating material composition is coated on a glass plate with a bar coater so that the dry film thickness is about 15 μm, and the maximum material temperature reaches 230 ° C. It is a value measured by using a gloss meter (manufactured by Big Chemie, Micro Trigloss).
Moreover, it is preferable that the compounding quantity of a matting agent (D) is 0.1-30 mass% with respect to the total amount of the said (A) component and (B) component, especially 0.5-20 mass%.

  The coating composition of the present invention is produced by uniformly mixing the components (A), (B), (E) and (C) and / or (D), and if necessary, the other components. be able to. Preferably, a pigment component other than the metallic pigment component (E) is mixed and dispersed in advance with a part of the resin component (A) and / or a pigment dispersant to prepare a pigment paste, and the pigment paste is used as the remaining components. It can be manufactured by mixing.

  The coating composition of the present invention can also be a one-pack type coating, but when it contains an organosilicate component (C) component, component (C) is separated from other components and immediately before use. It can also be made a two-component paint by mixing.

Coating film forming method The coating film forming method of the present invention comprises forming a primer coating film by coating a primer coating on one or both surfaces of a metal plate, and forming the primer coating film on at least one side of the primer coating film according to the present invention. It is a coating film forming method characterized by forming a top coating film with a contamination-resistant metallic paint composition.

  Examples of the metal plate to be coated in the coating film forming method of the present invention include cold rolled steel plate, hot dip galvanized steel plate, electrogalvanized steel plate, alloy galvanized steel plate (iron-zinc, aluminum-zinc, nickel-zinc, etc. Alloy galvanized steel plate), aluminum plate, stainless steel plate, copper plate, copper plated steel plate, tin plated steel plate and the like.

  When painting on metals, the metal surface, which is the material to be coated, may be painted as it is if it is not contaminated with oil or other pollutants, but it is well known for improving adhesion and corrosion resistance with the coating film. It is desirable to apply a metal surface treatment. These known surface treatment methods include phosphate surface treatment, chromate surface treatment, zirconium surface treatment and the like.

  As a primer coating for forming a primer coating on a metal plate, a known primer used in the field of colored color steel sheet coating, industrial machine coating, metal parts coating, etc. can be applied. Therefore, it is preferable to use a chromium-free primer coating that does not contain a chromium-based rust preventive component.

  The chrome-free primer coating is appropriately selected depending on the type of material to be coated and the type of metal surface treatment. Epoxy-based and polyester-based primer coatings and their modified primer coatings are particularly suitable, and workability is particularly required. In this case, a polyester primer paint is suitable.

  In addition, when adhesion with a lower layer coating such as a primer coating is particularly required, an epoxy primer coating, particularly a modified epoxy resin primer coating is preferred. Specific examples of the modified epoxy resin primer include, for example, (I) a bisphenol type modified with a soft organic component obtained by reacting 5 to 50% by mass of a soft organic component and 95 to 50% by mass of a bisphenol type epoxy resin. A coating composition containing an epoxy resin, (II) a curing agent, and (III) a rust preventive pigment, wherein the soft organic component in the resin (I) is an aliphatic polybasic acid having 4 to 36 carbon atoms, glass transition A primer coating composition characterized in that it is at least one of an acrylic resin having a temperature of -20 to 50 ° C and a polyester resin having a glass transition temperature of -20 to 50 ° C (see JP2009-256634) Can be mentioned.

  The primer coating is applied by a known coating method such as roll coating or spray coating so that the primer coating thickness is 1 to 30 μm, preferably 2 to 20 μm, and it is usually at an ambient temperature of 80 to 300 ° C. for 5 seconds. When pre-coating is applied for about 1 hour, it is preferably cured by heating for 15 seconds to 120 seconds under the condition that the maximum material reaching temperature is 140 to 250 ° C.

  The primer coating film may be a single layer or two layers in which a second primer coating film (intermediate coating film) is formed on the first primer coating film. When the primer film has two layers, the first primer film has an anticorrosion function, and the second primer film (intermediate film) has processability and chipping resistance. The primer coating can also have different functions.

  In the coating film forming method of the present invention, the stain-resistant metallic coating composition of the present invention is applied on at least one surface of the primer coating film. After adjusting the coating composition to the desired viscosity by adding an organic solvent, etc., if necessary, mention curtain coating, roll coater coating, dip coating, brush coating, bar coater coating, applicator coating, spray coating, etc. Usually, the coating film thickness after drying is 5 to 50 μm, preferably 7 to 30 μm.

  When the coating composition of the present invention is pre-coated, the coating method is not limited, but curtain coating and roll coater coating are recommended in view of the economy of pre-coated steel sheet coating. When roll coater coating is applied, the bottom feed method (so-called natural reverse coating or natural coating) with a normal two-roll is practically performed, but the uniformity of the coating surface is best. Therefore, a top feed or bottom feed method using three rolls can be performed. The curing condition of the top coat film by the coating composition of the present invention is usually about 15 seconds to 30 minutes at a material maximum temperature of 120 to 260 ° C. In the field of pre-coating, which is applied by coil coating or the like, it is usually carried out at a raw material maximum temperature of 160 to 260 ° C. for a baking time of 15 to 90 seconds.

In the visible light region having a wavelength of 310 to 350 nm, the light transmittance of the cured coating film coated with the coating composition of the present invention with a film thickness of 15 μm and cured by heating is 5% or less on average, 2% or less on average, and more particularly average It is preferable that it is 0.5% or less from a viewpoint of the weather resistance of a coating film.
In addition, from the viewpoints of weather resistance, water resistance and processability of the coating film, the glass transition temperature of the cured coating film is in the range of 30 to 100 ° C., further 45 to 90 ° C., more particularly 60 to 80 ° C. Is preferred.

  Hereinafter, the present invention will be described more specifically with reference to production examples and examples. The present invention is not limited to the following examples. Hereinafter, “parts” and “%” are based on mass.

Production and production example 1 of polyester resin
The following raw materials were charged into a flask equipped with a thermometer, a stirrer, a heating device, and a rectifying tower.
1,2-cyclohexanedicarboxylic anhydride 150.9 parts (0.98 mol)
Neopentyl glycol 42.0 parts (0.40 mol)
4.8 parts (0.03 mol) of butylethylpropanediol
77.8 parts (0.57 mol) of trimethylolpropane
Coconut fatty acid 44.1 parts (0.21 mol)
Dibutyltin oxide (catalyst) 0.03 part Next, the temperature was raised to 160 ° C. while stirring the contents, the temperature was gradually raised from 160 ° C. to 230 ° C. over 3 hours, and the reaction was continued at 230 ° C. for 30 minutes. In order to replace the rectification column with a water separator and promote removal of by-product condensed water, 5% xylene was added to the total charge, and the reaction was further proceeded at 230 ° C., with an acid value of 4 mgKOH / When it became g, the heating was stopped, and swathol 1500 (hydrocarbon solvent) was added to dilute to obtain a fatty acid-modified polyester resin (A1-1) solution having a solid content of 65%.

  The obtained resin has a number average molecular weight of 15,000, a hydroxyl value (mg number of potassium hydroxide required to neutralize 1 g of resin) 75 mgKOH / g, oil length 14.7%, iodine value 5>. It was.

Production Examples 2 to 13
In the same manner as in Production Example 1 with the formulation shown in Table 1 below, solutions of each fatty acid-modified polyester resin (A1-2) to (A1-13) having a solid content of 65% were obtained. The composition ratio of each component in Table 1 is a molar ratio.
Table 1 shows the number average molecular weight, hydroxyl value, oil length, and iodine value of each resin. In addition, the fatty acid modified polyester resins (A1-7) to (A1-13) in Production Examples 7 to 13 are resins for comparative examples.

Production and production example 14 of copolymer resin (F)
In a flask equipped with a thermometer, a reflux condenser, and a stirrer, 28 parts of Swazol 1000 (manufactured by Cosmo Oil Co., Ltd., aromatic hydrocarbon organic solvent) and 85 parts of toluene were added, and then N, N-dimethylamino was added. A mixture of 10 parts of ethyl methacrylate, 50 parts of 1-vinyl-2-pyrrolidone, 10 parts of 2-hydroxyethyl methacrylate, 30 parts of 2-ethylhexyl methacrylate and 4 parts of azobismethylbutyronitrile is reacted at 110 ° C. under nitrogen gas. I let you. Next, the solid content was adjusted with toluene to obtain a copolymer resin (F-1) solution having a solid content of 55% by mass. The copolymer resin (F-1) solution had an amine value of 35 mgKOH / g, a hydroxyl value of 43 mgKOH / g, and a weight average molecular weight of 11,000.

Production Example 15
In a flask equipped with a thermometer, a reflux condenser, and a stirrer, 28 parts of Swazol 1000 (manufactured by Cosmo Oil Co., Ltd., aromatic hydrocarbon organic solvent) and 85 parts of toluene were added, and then N, N-dimethylamino was added. A mixture of 15 parts of ethyl methacrylate, 25 parts of methyl methacrylate, 10 parts of 2-hydroxyethyl methacrylate, 50 parts of 2-ethylhexyl methacrylate and 4 parts of azobismethylbutyronitrile was reacted at 110 ° C. under nitrogen gas. Next, the solid content was adjusted with toluene to obtain a copolymer resin (F-2) solution having a solid content of 55% by mass. The copolymer resin (F-2) solution had an amine value of 52 mgKOH / g, a hydroxyl value of 43 mgKOH / g, and a weight average molecular weight of 10,000.

Production of primer coating composition
Soft acrylic modified epoxy resin primer coating composition (PR1)
Production Example 16
To 200 parts of the following modified bisphenol-type epoxy resin solution (80 parts by solid content), 20 parts of vanadium pentoxide, 20 parts of calcium metasilicate, 20 parts of calcium phosphate, 20 parts of titanium white, 20 parts of barita and mixed solvent 3 [Swazole 1500 / A suitable amount of cyclohexanone = 1/1 (mass ratio)] was mixed, and the pigment was dispersed until the tube (particle diameter of the coarse pigment particles) became 20 microns or less. Next, 26.7 parts (20 parts by solid content) of Desmodur BL-3175 (manufactured by Sumika Bayer Urethane Co., Ltd., HDI isocyanurate type polyisocyanate compound solution blocked with methyl ethyl ketoxime, solid content of about 75%) was added to this dispersion. ), Takenate TK-1 (manufactured by Takeda Pharmaceutical Co., Ltd., organotin blocking agent dissociation catalyst, solid content of about 10%), and uniformly mixed, and further mixed solvent 2 and viscosity of about 80 seconds (Ford Cup # 4/25 ° C.) to obtain a soft acrylic-modified epoxy resin primer coating composition (PR1).

Modified bisphenol type epoxy resin solution: In a flask equipped with a stirrer, a condenser and a thermometer, 60 parts of cyclohexanone and 90 parts of jER1007 (bisphenol A type epoxy resin by Japan Epoxy Resin, epoxy equivalent of about 1800) are blended, and the temperature is 130 ° C. And the epoxy resin was dissolved. After confirming that the epoxy resin was completely dissolved, an epoxy resin solution having a solid content of 60% was obtained. To 150 parts of the obtained epoxy resin solution having a solid content of 60%, 20 parts of the following 50% soft acrylic resin solution (10 parts in solid content) and 0.5 part of tetraethylammonium bromide are added, and the temperature is maintained at 130 ° C. The reaction was performed for 3 to 4 hours. Confirm that the resin acid value is 1 or less, and add mixed solvent 1 [cyclohexanone / swazol 1000 (manufactured by Maruzen Petrochemical Co., Ltd., high boiling aromatic petroleum solvent) = 1/2 (mass ratio)] A resin solution having a solid content of 40% was obtained.
Soft acrylic resin solution: 65.0 parts of Swazol 1000 (manufactured by Maruzen Petrochemical Co., Ltd., high-boiling aromatic petroleum-based solvent) is put into a flask equipped with a stirrer, a condenser, a thermometer, a nitrogen introducing tube and a dropping device. While stirring, the temperature in the reaction vessel was raised to 110 ° C. and maintained at a temperature of 110 ° C., while 18.4 parts of styrene, 31.2 parts of methyl methacrylate, 37.5 parts of n-butyl acrylate, acrylic acid A mixture of 11.0 parts of 2-hydroxyethyl, 1.9 parts of acrylic acid and 1.7 parts of 2,2′-azobisisobutyronitrile was added dropwise over 3 hours. After completion of the dropwise addition, 0.5 part of 2,2′-azobisisobutyronitrile was further added, the mixture was further reacted at the same temperature for 2 hours, 35.0 parts of cyclohexanone was added, and a soft acrylic resin having a solid content of 50% was added. A resin solution was obtained. The obtained soft acrylic resin had an acid value of 15 mgKOH / g, a hydroxyl value of 53 mgKOH / g, a glass transition temperature of 5 ° C., and a number average molecular weight of about 10,000.
Polyester-modified epoxy resin primer coating composition (PR2)
Production Example 17
To 200 parts of the following modified bisphenol-type epoxy resin solution (80 parts by solid content), 20 parts of vanadium pentoxide, 20 parts of calcium metasilicate, 20 parts of calcium phosphate, 20 parts of titanium white, 20 parts of barita and mixed solvent 3 [Swazole 1500 / A suitable amount of cyclohexanone = 1/1 (mass ratio)] was mixed, and the pigment was dispersed until the tube (particle diameter of the coarse pigment particles) became 20 microns or less. Next, 26.7 parts (20 parts by solid content) of Desmodur BL-3175 (manufactured by Sumika Bayer Urethane Co., Ltd., HDI isocyanurate type polyisocyanate compound solution blocked with methyl ethyl ketoxime, solid content of about 75%) was added to this dispersion. ), Takenate TK-1 (manufactured by Takeda Pharmaceutical Co., Ltd., organotin blocking agent dissociation catalyst, solid content of about 10%), and uniformly mixed, and further mixed solvent 2 and viscosity of about 80 seconds (Ford Cup # 4/25 ° C.) to obtain a polyester resin primer coating composition (PR2).

Modified bisphenol-type epoxy resin solution: Into a flask equipped with a stirrer, a condenser and a thermometer, 60 parts of cyclohexanone and 80 parts of jER1007 (Japan Epoxy Resin bisphenol A-type epoxy resin, epoxy equivalent of about 1800) are blended, and the temperature is 130 ° C. And the epoxy resin was dissolved. After confirming that the epoxy resin was completely dissolved, an epoxy resin solution having a solid content of 60% was obtained. To 150 parts of the obtained epoxy resin solution with a solid content of 60%, 28.6 parts of the following 70% polyester resin solution (20 parts in terms of solid content) and 0.5 part of tetraethylammonium bromide are added and maintained at a temperature of 130 ° C. And reacted for 3 to 4 hours. Confirm that the resin acid value is 1 or less, and add mixed solvent 1 [cyclohexanone / swazol 1000 (manufactured by Maruzen Petrochemical Co., Ltd., high boiling aromatic petroleum solvent) = 1/2 (mass ratio)] A modified bisphenol type epoxy resin solution having a solid content of 40% was obtained.
Polyester resin solution: In a reactor equipped with a stirring device, a heating device, a thermometer, a separation device and a distillate storage tank, 105 parts of neopentyl glycol, 354 parts of 1,6-hexanediol, 564 parts of hexahydrophthalic anhydride and A raw material mixture of 123 parts of adipic acid was added and heating was started. When stirring became possible after the start of heating, stirring was started, the temperature was raised to 240 ° C. while removing condensed water, and the reaction was continued at the same temperature. When the outflow of water stopped after about 1.5 hours, 40 parts of xylene was added to promote the reaction, dehydration condensation was continued, and the reaction was continued until the acid value reached 52. Next, the mixture was cooled and 417 parts of cyclohexanone was added for dilution to obtain a polyester resin solution having a solid content of 70%. The obtained resin had a glass transition temperature of −19 ° C. and a number average molecular weight of 2100.

Production and Performance Test of Antifouling Metallic Coating Composition Examples 1-36, Comparative Examples 1-14 and Reference Example 1
A paint was formed with the composition shown in Table 2 below, and each of the anti-stain metallic coating compositions No. 1-49 were obtained. Contamination resistant metallic paint composition No. Nos. 35 to 48 are for a comparative example, a contamination-resistant metallic coating composition No. 49 is a coating composition for reference examples. -
As shown in Table 2, KP color 8510 primer (trade name, manufactured by Kansai Paint Co., Ltd., pre-coated on a molten 55% aluminum-zinc plated steel plate (galvalume steel plate) having a thickness of 0.35 mm subjected to chemical conversion treatment Epoxy resin-based strontium chromate primer for steel sheet), soft acrylic-modified epoxy resin-based non-chrome primer coating composition (PR1) described in Production Example 16 or polyester-modified epoxy resin-based non-chrome primer coating composition described in Manufacturing Example 17 (PR2) was coated so that the dry film thickness was 5 μm, heated so that the maximum material arrival temperature was 220 ° C., and baked for 40 seconds to obtain a primer-coated steel sheet. Each primer-coated steel coating composition obtained as described above is coated on this primer-coated steel sheet with a bar coater so that the dry film thickness is about 15 μm, and heated so that the maximum material temperature reaches 230 ° C. Then, each coated steel sheet was obtained by baking for 50 seconds. The following performance test was done about each obtained coated steel plate.

  The test results are also shown in Table 2. In addition, the quantity of each component in Table 2 is solid content mass. A mixed solvent of cyclohexanone / swazol 1500 (manufactured by Maruzen Petroleum Co., Ltd., aromatic high-boiling solvent) = 60/40 (mass ratio) was used for adjusting the viscosity of the coating composition. During coating, the viscosity of the coating composition was adjusted to about 100 seconds (25 ° C.) with Ford Cup # 4.

  In Table 2, (Note 1) to (Note 25) are as follows.

  Uban 20SE-60 (Note 1): trade name, manufactured by Mitsui Chemicals, butyl etherified melamine resin, weight average molecular weight of about 4000.

  Super Becamine J820-60 (Note 2): trade name, manufactured by DIC Corporation, n-butyl etherified melamine resin solution.

  Super Becamine L-118-60 (Note 3): trade name, manufactured by DIC Corporation, n-butyl etherified melamine resin solution.

  Cymel 303 (Note 4): Product name, manufactured by Nippon Cytec Industries Co., Ltd., low molecular weight methylated melamine resin. The content of hexakis (methoxymethyl) melamine is 60% by weight or more.

  Sumidur BL3175 (Note 5): Trade name, manufactured by Sumika Bayer Urethane Co., Ltd., a methyl ethyl ketone oxime block compound of trimethylolpropane adduct type hexamethylene diisocyanate.

  MS56S (Note 6): Trade name, manufactured by Mitsubishi Chemical Corporation, trade name “MKC silicate MS56S”, methyl esterified silicate which is a condensate of tetramethoxysilane.

  MS58B30 (Note 7): Trade name, manufactured by Mitsubishi Chemical Corporation, trade name “MKC silicate MS58B30”, methyl / butyl mixed esterified silicate which is a condensate of tetraalkoxysilane, and the ratio of methyl / butyl number is 70/30.

  X-41-1805 (Note 8): Trade name, manufactured by Shin-Etsu Chemical Co., Ltd., trade name, condensate of mercaptoalkyl group-containing trialkoxysilane, mercaptoalkyl group has 18 or less carbon atoms, alkoxy group has 6 carbon atoms It is as follows.

  New Coal 210 (Note 9): Trade name, manufactured by Nippon Emulsifier, dodecylbenzenesulfonate.

  New Coal 291-GL (Note 10): trade name, manufactured by Nippon Emulsifier Co., Ltd., dialkylsulfosuccinic acid sodium salt.

  New Coal 292-PG (Note 11): trade name, manufactured by Nippon Emulsifier Co., Ltd., dialkylsulfosuccinic acid sodium salt.

  New Coal 293 (Note 12): trade name, manufactured by Nippon Emulsifier Co., Ltd., monoalkylsulfosuccinic acid disodium salt.

  Riquemar S-71-D (Note 13): trade name, manufactured by Riken Vitamin Co., Ltd., diglycerin stearate, HLB value 5.7.

  Riquemar C250 (Note 14): trade name, manufactured by Riken Vitamin Co., sorbitan caprylate, HLB value 10.6.

  Aluminum paste M-301 (Note 15): trade name, manufactured by Asahi Kasei Chemicals Corporation, aluminum pigment, average particle size 19 μm.

  Aluminum paste 1100M (Note 16): trade name, manufactured by Toyo Aluminum Co., Ltd., aluminum pigment, average particle size 26.3 μm.

  Aluminum paste 1109M (Note 17): trade name, manufactured by Toyo Aluminum Co., Ltd., aluminum pigment, average particle size of 34.6 μm.

  Aluminum paste FZ-N30 (Note 18): trade name, manufactured by Toyo Aluminum Co., Ltd., resin-coated aluminum pigment, average particle diameter of 17.9 μm.

  Alpest FX-1440 (Note 19): trade name, manufactured by Toyo Aluminum Co., Ltd., resin-coated aluminum pigment, average particle size of 28.5 μm.

  Thyroid 161W (Note 20): trade name, manufactured by GRACE GMBH, trade name, finely treated silica fine powder, oil absorption 170 ml / 100 g.

  Nacure 5225 (Note 21): Trade name, manufactured by King Industries, USA, an isopropanol solution of a secondary amine neutralized product of dodecylbenzenesulfonic acid. The degree of neutralization of dodecylbenzenesulfonic acid / amine is about 1.1 (molar ratio). The active ingredient is about 33% by weight, of which dodecylbenzenesulfonic acid / amine (mass ratio) is about 8/25. The numerical values in the table are parts by mass of solid content of dodecylbenzenesulfonic acid.

  Formate TK-1 (Note 22): Trade name, manufactured by Takeda Pharmaceutical Co., Ltd., a curing catalyst that is an organic tin solution, and a dissociation catalyst for a blocked polyisocyanate compound.

  Desparon L1982 (Note 23): Trade name, manufactured by Enomoto Kasei Co., Ltd., acrylic resin surface conditioner.

  BYK1790 (Note 24): trade name, manufactured by Big Chemie, a polyethylene antifoaming agent.

  KP Color 8510 Primer (Note 25): Trade name, manufactured by Kansai Paint Co., Ltd., epoxy resin-based strontium chromate primer for pre-coated steel sheets.

  The performance test in Table 2 was conducted according to the following method and evaluation criteria.

  60 ° gloss value: Each stain-resistant metallic paint composition is coated on a glass plate with a bar coater so that the dry film thickness is about 15 μm, and heated so that the maximum material temperature reaches 230 ° C. for 50 seconds. After baking, a 60 ° gloss value was measured using a gloss meter (manufactured by Big Chemie, Micro Trigloss).

Light transmittance: Each paint composition was applied to a tin plate so as to have a dry film thickness of 15 μm, baked for 50 seconds so that the maximum material temperature reached 230 ° C., and then the coating film peeled off by the mercury amalgam method, Measurements were made using a visible to ultraviolet spectrophotometer. At a wavelength of 310 to 350 nm, the transmittance with respect to a blank (air) was measured and ranked according to the following.
A: 0.5% or less B: Over 0.5% to 2% or less C: Over 2% to 5% or less D: Over 5%

Glass transition temperature: Each paint composition was applied to a tin plate so as to have a dry film thickness of 70 μm, baked for 50 seconds so that the maximum material reaching temperature was 230 ° C., and then the coating film peeled off by the mercury amalgam method, It is a dynamic glass transition temperature (° C.) of a coating film measured using an FT rheology spectrumr “Rheogel E-400” (manufactured by UBM Co., Ltd.) at a frequency of 110 Hz and a heating rate of 4 ° C./min. Ranking according to the following.
A: Less than 30 ° C B: 30 ° C or more and less than 60 ° C C: 60 ° C or more and less than 80 ° C D: 80 ° C or more.

Workability: In a room at 20 ° C., the test plate was bent 180 degrees with three sheets of the same thickness as the test plate inside the bent portion with the coated surface facing outside. The result was evaluated by the ratio of the crack length to the processed part.
◎: There is no cracking in the coating film of the processed part ○: There is cracking in the coating film in the processing part (length of cracking: less than 25%)
Δ: Cracks in the coating film of the processed part (length of cracks: 25% or more and less than 50%)
X: There is crack in the coating film of the processed part (length of crack: 50% or more).

Outdoor exposure test: An outdoor exposure test specimen (100 x 300 mm) is mounted on the installation stand that models the eaves so that the coating film faces the north side, and exposed on the roof of Kansai Paint Co., Ltd. in Kanzaki-cho, Amagasaki City. The test was conducted, and the stain resistance and rain-stain stain resistance (rain-stained stains) were evaluated according to the following criteria. Contamination resistance was measured by using a multi-light source spectrocolorimeter MSC-5N manufactured by Suga Test Instruments Co., Ltd., based on JIS Z8370, the color difference (ΔE) before and after exposure. Rain resistance stain resistance was judged visually.
<Contamination resistance>
Evaluation was made according to the following criteria by ΔE before and after the outdoor exposure test.
：: ΔE is less than 2, ◯: ΔE is 2 or more and less than 3, Δ: ΔE is 3 or more and less than 5, x: ΔE is 5 or more.
<Rain-stain stain resistance>
The rain streak after the outdoor exposure test was evaluated according to the following criteria.
A: Rain traces are not observed, ○: Rain traces are slightly observed, Δ: Rain traces are considerably observed, X: Rain traces remain dark.

Boiling water resistance: Each test coating plate cut to a size of 5 cm × 10 cm was immersed in boiling water at about 100 ° C. for 5 hours, and then pulled up so that the appearance of the coating film on the surface side was compared with the test plate before boiling water immersion. The color difference (ΔE) was measured and evaluated according to the following criteria.
A: ΔE is less than 0.5 B: ΔE is 0.5 or more and less than 2.0 Δ: ΔE is 2.0 or more and less than 5.0 x: ΔE is 5.0 or more.

Salt spray resistance: The appearance of the coating film after 1000 hours of salt spray test was evaluated according to the following criteria.
A: No abnormality is observed. B: Slight swelling is observed. Or, when the cellophane tape is peeled off from the coated plate in the cellophane tape adhesion test, a slight amount of rust adhesion is observed.
Δ: Swelling is observed. Or, when the cellophane tape is peeled off from the coated plate in the cellophane tape adhesion test, the coating film is slightly peeled off.
X: Remarkable swelling is recognized. Or, when the cellophane tape is peeled off from the coated plate in the cellophane tape adhesion test, peeling of the coating film is observed.

Accelerated weather resistance: xenon accelerated weathering tester 3000 test appearance after test (measure color difference (ΔE) from test plate before test) and adhesion (cross grid (2 mm x 2 mm is 100) cellophane The tape peeling test was evaluated according to the following criteria.
<Appearance change>
A: ΔE is less than 1.5 ○: ΔE is 1.5 or more and less than 3.0 Δ: ΔE is 3.0 or more and less than 7.0 ×: ΔE is 7.0 or more <Adhesiveness>
A: No separation is observed B: 90 or more grids remain.
Δ: 50 or more and less than 90 grids remain.
X: Less than 50 grids remain.

Claims (13)

The total content of the alicyclic polybasic acid (a1-1) obtained by the reaction of the polybasic acid component (a1), the alcohol component (a2) and the fatty acid (a3) and the polybasic acid component (a1) is A fatty acid-modified polyester resin having a number average molecular weight of 4000 to 25000, a hydroxyl value of 5 to 100 mgKOH / g, and an oil length of 3 to 35% in a range of 50 to 100 mol% based on the total amount of the polybasic acid component (a1) Polyester resin component (A) containing 50 to 100% by mass of (A1), Crosslinker component (B) containing 50 to 100% by mass of butyl etherified melamine resin (B1), general formula: (R ¹ ) _n -Si — (OR ² ) _4-n (wherein R ¹ is an alkyl or phenyl group having 1 to 18 carbon atoms which may be substituted with an epoxy group or a mercapto group, and R ² has 1 to 6 carbon atoms) No A coating composition containing an organosilicate component (C) and / or a surfactant component (D) having the following characteristics, and a metallic pigment component (E): And based on the total solid content of component (A) and component (B),
(A) Content of a component is 50-95 mass%,
(B) Content of a component is 5-50 mass%,
Content of (C) component and / or (D) component is 0.1-20 mass%,
(E) Content of component is 10 to 60% by mass
A contamination-resistant metallic paint composition characterized by
Surfactant component (D): anionic surfactant having at least one nonionic surfactant (D-1) selected from polyethylene glycol fatty acid ester, sorbitan fatty acid ester and glycerin fatty acid ester and / or sulfosuccinate group (D-2). The content of 1,2-cyclohexanedicarboxylic acid and / or 1,2-cyclohexanedicarboxylic anhydride in the polybasic acid component (a1) is 50 to 100 mol based on the total amount of the polybasic acid component (a1). % Antifouling metallic paint composition according to claim 1, characterized in that it is in the range of%. The content of neopentyl glycol in the alcohol component (a2) is in the range of 25 to 100 mol% based on the total amount of the alcohol component (a2), and the resistance to resistance according to claim 1 or 2. Contaminated metallic paint composition. An amino group or a quaternary ammonium base-containing polymerizable unsaturated monomer, a polymerizable unsaturated monomer having a nitrogen atom-containing heterocyclic ring, and N-substituted may be substituted (meth) with respect to the total amount of all the constituent monomers. A copolymer resin (F) comprising at least one polymerizable unsaturated monomer 20 to 70% by mass selected from acrylamide compounds and other polymerizable unsaturated monomer 30 to 80% by mass as a constituent component (A) The antifouling metallic coating composition according to any one of claims 1 to 3, which is contained in an amount of 0.1 to 20% by mass based on the total amount of the solid content of the component and the component (B). The metallic pigment component (E) is an aluminum pigment, and the average particle diameter of the aluminum pigment is in the range of 5 to 33 µm, The contamination-resistant metallic material according to any one of claims 1 to 4, Paint composition. The aluminum pigment according to claim 5 is a resin-coated aluminum pigment. The glass transition temperature of the cured coating film which heat-cured the coating composition of any one of Claims 1-6 is 30-100 degreeC, The antifouling metallic coating composition characterized by the above-mentioned. The coating composition according to any one of claims 1 to 7 contains a matting agent, and a 60 ° gloss value of a cured coating film obtained by heating and curing the coating composition is less than 60%. Contamination resistant metallic paint composition. The light transmittance of the cured coating film coated with the coating composition according to any one of claims 1 to 8 at a film thickness of 15 μm and heat-cured is an average of 5% or less at a wavelength of 310 to 350 nm. A feature of a stain resistant metallic coating composition.   A primer coating film is formed on a metal plate, and the antifouling metallic coating composition according to any one of claims 1 to 9 is applied onto the primer coating film to form an overcoat having a thickness of 5 to 50 µm. A method of forming a coating film, comprising forming a film.   The coating film forming method according to claim 10, wherein the primer coating is a chromium-free primer coating that does not contain a chromium-based anticorrosive component.   The primer paint comprises (I) a bisphenol type epoxy resin modified with a soft organic component obtained by reacting 5 to 50% by mass of a soft organic component and 95 to 50% by mass of a bisphenol type epoxy resin, (II) a curing agent, and (III) A coating composition containing a rust preventive pigment, wherein the soft organic component in the resin (I) is an aliphatic polybasic acid having 4 to 36 carbon atoms and an acrylic resin having a glass transition temperature of -20 to 50 ° C The method for forming a coating film according to claim 10 or 11, wherein the primer coating composition is at least one of a resin and a polyester resin having a glass transition temperature of -20 to 50 ° C. The coating metal plate which has a multilayer coating film formed by the coating-film formation method of any one of Claims 10-12.