JP2002146295A - Topcoating material composition and coated product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a topcoating material composition which can form coating films having excellent weatherability, water resistance, chemical resistance, stain resistance, and mar resistance. SOLUTION: The topcoating material composition comprises, as the nonvolatile components, (a) 10-70 pts.mass curing agent component having a functional group capable reacting with hydroxyl group, (b) 30-90 pts.mass resin component having, in the molecule, two or more hydroxyl group-terminated chain atomic groups to be obtained by reacting a cyclic compound selected from an oxirane compound, a lactone compound, and an oxetane compound with hydroxyl group, and (c) 0.01-20 pts.mass compound having a hydrolyzable alkoxy or aryloxy group which is directly bonded to a silicon atom.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to weather resistance, water resistance,
The present invention relates to a novel topcoat composition capable of forming a coating film having excellent chemical resistance, stain resistance and scratch resistance, and a coated article obtained by applying the topcoat composition.

[0002]

2. Description of the Related Art In recent years, the demand for durability of a coating film formed on a top coating material used for forming a coating film on automobiles, building materials, plastic parts, and the like has increased, and heat, light, water, and the like have been demanded. It is required to maintain the initial coating appearance quality for as long as one year against external loads such as chemical substances, physical destruction, and stain adhesion. Based on such demands, conventionally, in order to improve the durability of the coating film, it has been mainly dealt with by applying a fluororesin coating. For example, JP-A-5-1058
No. 39 discloses a top coat paint composition containing a fluorine-containing copolymer containing no chlorine atom, a vinyl pivalate unit and a hydroxyalkyl vinyl ether unit, a melamine resin, and a blocked acid catalyst as main components. The article discloses that a top coat capable of maintaining excellent water repellency and weather resistance for a long period of time can be provided. JP-A-6-25592 discloses a coating resin composition comprising a hydroxyl group-containing fluororesin, a lactone-modified acrylic resin, and a curing agent capable of reacting with a hydroxyl group, and has weather resistance, water resistance, and stain resistance. ,
There is a description that a coating film excellent in solvent resistance, chemical resistance, transparency, gloss, flexibility, hardness, workability, and the like can be provided. Furthermore, International Publication WO-94 / 06870 discloses a coating composition comprising a specific organic coating composition and a specific organosilicate and / or a condensate thereof, which provides weather resistance and stain resistance. There is a description that a coating film having excellent properties can be formed.

[0003]

However, in the methods disclosed in JP-A-5-105839 and JP-A-6-25592, in each case, a fluorocarbon resin is used instead of a normal hydrocarbon resin. Although the durability of the film is improved, there is a problem that oily dirt, carbon dirt and the like are liable to adhere due to the lipophilicity inherent to fluorine atoms. In the method disclosed in International Publication WO-94 / 06870, a silicate condensate may be non-uniformly present in the inside of a cured coating film, and water resistance such as partial whitening of the coating film when exposed to water. There was a tendency to decrease. An object of the present invention is to provide a top coating composition capable of forming a coating film capable of maintaining high weather resistance, water resistance, chemical resistance, stain resistance, and scratch resistance over a long period of time immediately after coating film formation, And a coated article obtained by applying the overcoat composition.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to develop a coating composition having the above-mentioned preferable properties. As a result, (a) a curing agent component having a functional group capable of reacting with a hydroxyl group, (B) a resin component containing in a molecule two or more chain atomic groups having a hydroxyl group at a terminal obtained by reacting a cyclic compound selected from an oxirane compound, a lactone compound and an oxetane compound with a hydroxyl group; A compound having a hydrolyzable alkoxy group or an aryloxy group directly bonded to a silicon atom, and a top coating composition containing a non-volatile component containing a particle component of (d) an inorganic oxide sol optionally used in a specific ratio, The inventors have found that the object can be achieved, and have completed the present invention. That is, the present invention provides (a) 10 to 70 parts by mass of a curing agent component having a functional group capable of reacting with a hydroxyl group, and (b) a reaction between a hydroxyl compound and a cyclic compound selected from oxirane compounds, lactone compounds and oxetane compounds. 30 to 90 parts by mass of a resin component having two or more chain atomic groups having a hydroxyl group at the terminal to be obtained, and (c) a compound 0.01 having a hydrolyzable alkoxy group or aryloxy group directly bonded to a silicon atom It is intended to provide a top coating composition characterized by containing up to 20 parts by mass of a nonvolatile component.

Further, the present invention provides the above top coating composition, further comprising: (d) a particle component of inorganic oxide sol.
It is intended to provide a top coating composition containing 5 to 30 parts by mass. The present invention also provides a topcoat composition wherein the component (a) contains at least one selected from an amino resin, a polyisocyanate compound, a blocked polyisocyanate compound and a carbamate compound in the above topcoat composition. Is what you do. Further, the present invention provides the above top coating composition, wherein the component (b) is 1 to 10 mol of a cyclic compound selected from oxirane compounds, lactone compounds and oxetane compounds and 1
It is an object of the present invention to provide a top coating composition which is an acrylic resin component containing two or more chain atomic groups having a hydroxyl group at a terminal obtained by a mole reaction in one molecule. In the present invention, the component (c) may be a compound represented by the general formula (1):

[0006]

(R ¹ ) _n -Si- (OR ² ) _4-n (1) (wherein, R ¹ and R ² are each a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkyl group having 6 to 10 carbon atoms) Wherein at least one of R ² is an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms,
A plurality of R ² may be the same or different,
n is 0 or 1. The present invention provides an overcoat composition which is an organosilicate represented by the formula (1) and / or a condensate thereof. Further, the present invention provides the above top coating composition, wherein the component (d) is at least one inorganic material selected from among aluminum oxide sol, silicon oxide sol, zirconium oxide sol, antimony oxide sol, zinc oxide sol and titanium oxide sol. An object of the present invention is to provide a top coating composition which is a particle component of an oxide sol. Furthermore, the present invention provides a coated article obtained by applying the above top coating composition.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The component (a) used in the present invention is a curing agent component having a functional group capable of reacting with a hydroxyl group,
By mainly performing a curing reaction with the resin component (b), a coating film having excellent durability can be formed. Examples of such a curing agent component include an amino resin, a polyisocyanate compound, a blocked polyisocyanate compound and a carbamate compound, and they can be used alone or as a mixture of two or more. Examples of the amino resin include a melamine resin, a guanamine resin, a urea resin, and a glycoluril resin. Among them, a melamine resin is more preferably used. Specific examples of the melamine resin include, for example, Uban series (trade name, manufactured by Mitsui Chemicals, Inc.), Super Beckamine series (trade name, manufactured by Dainippon Ink and Chemicals, Inc.), Melan series (trade name, Hitachi Butylated melamine resin or isobutylated melamine resin such as Kasei Kogyo Co., Ltd., Cymel series (trade name, Mitsui Cytec Co., Ltd.)
Melamine resin, such as Nicarac series (trade name, manufactured by Sanwa Chemical Co., Ltd.), alkylated melamine resin mixed with methylbutyl or alkylated melamine resin mixed with methylisobutyl.

Examples of polyisocyanate compounds include toluene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, hydrogenated diphenylmethane diisocyanate, and hydrogenated xylene diisocyanate. And / or adducts, burettes and isocyanurates thereof. Among them, preferred are adducts, burettes, or isocyanurates of non-yellowing polyisocyanate compounds such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and isophorone diisocyanate.

As the blocked polyisocyanate compound, the above-mentioned polyisocyanate compounds can be used, for example, phenols such as phenol, m-cresol, xylerol and thiophenol, alcohols such as methanol, ethanol, butanol, 2-ethylhexanol and cyclohexanol. Compounds, active hydrogen-containing compounds such as ethyl acetoacetate and diethyl malonate, azoles such as 3,5-dimethylpyrazole and triazole, oximes such as methyl ethyl ketone oxime and cyclohexanone oxime, and those blocked with caprolactam and the like. it can. Among them, preferred are an adduct of a non-yellowing type polyisocyanate compound such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and isophorone diisocyanate; an active hydrogen-containing compound such as ethyl acetoacetate of a burette or isocyanurate; and diethyl malonate; ,
It is a block formed by azoles such as 5-dimethylpyrazole and triazole, and methyl ethyl ketone oxime. Further, as the carbamate compound, for example, a compound represented by the general formula (2)

[0010]

## STR3 ## _{C 3 N 3 (NHCOOR) 3} (2) ( wherein, R is an alkyl group, an aryl group or an aralkyl group having 7 to 20 carbon atoms having 1 to 20 carbon atoms, plural R
May be the same or different. 1,3)
5-triazine-2,4,6-tris-carbamic acid ester can be mentioned.

The 1,3,5- represented by the general formula (2)
Specific examples of R in triazine-2,4,6-tris-carbamic acid ester include a methyl group, an ethyl group,
n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group,
C 1-20 such as decyl group, undecyl group, dodecyl group, tetradecyl group, heptadecyl group, icosyl group
An alkyl group, a phenyl group, a tolyl group, a naphthyl group, an anthryl group, an aryl group having 6 to 20 carbon atoms such as a substituted aryl group in which an aromatic ring of these groups is substituted by the alkyl group, a benzyl group, a phenethyl group, And an aralkyl group having 7 to 20 carbon atoms, such as a substituted aralkyl group in which the above-mentioned alkyl group is substituted on the aromatic ring of the above group. Further, these 1,3,5-triazine-2,4,6-tris-
Among the carbamic acid esters, compounds in which R is an alkyl group having 1 to 8 carbon atoms are preferable, and particularly, C ₃ N ₃ (N
2,4,6-tris- represented by HCOOCH ₃ ) ₃
2, represented by (methoxycarbonylamino) -1,3,5-triazine, C ₃ N ₃ (NHCOOC ₄ H ₉ ) ₃
4,6-tris- (butoxycarbonylamino) -1,
3,5-Triazine and mixtures thereof are preferred.
Furthermore, 1,3,5-triazine-2,4,6-tris
-An oligomer in which a carbamate is partially condensed with a diol can be used. The diols used here include, for example, ethylene glycol, diethylene glycol, propylene glycol, propane diol, butane diol, pentane diol, hexane diol, neopentyl diol and the like.

The component (a) of the present invention comprises 10 to 70 parts by mass, preferably 15 to 60 parts by mass, more preferably 20 parts by mass.
It is used in the range of ５０50 parts by mass. Here, when the amount of the component (a) is less than 10 parts by mass, the solvent resistance of the cured coating film is unfavorably deteriorated. The component (b) used in the present invention comprises, in a molecule, two or more chain atomic groups having a hydroxyl group at a terminal obtained by reacting a cyclic compound selected from an oxirane compound, a lactone compound and an oxetane compound with a hydroxyl group. It is a resin component having.
The component (b) has good compatibility with the component (c), so that the component (c) is uniformly present and good water resistance can be maintained. The chain atomic group having a hydroxyl group at the terminal in the component (b) is effective for imparting rubber elasticity to the cured coating film and improving scratch resistance.

The hydroxyl group which reacts with a cyclic compound selected from oxirane compounds, lactone compounds and oxetane compounds is preferably a hydroxyl group bonded to an organic group. A compound having an organic group bonded to a hydroxyl group, that is,
Preferred examples of the hydroxyl group-containing organic compound include resins such as a hydroxyl group-containing vinyl resin, a hydroxyl group-containing polyester resin, and a hydroxyl group-containing polyester resin, and a hydroxyl group-containing vinyl resin is particularly preferable. The chain atomic group having a hydroxyl group at the terminal may be linear or branched. The chain atomic group having a hydroxyl group at the terminal is an oxirane compound, a lactone compound and a molar ratio of a hydroxyl group which reacts with a cyclic compound selected from oxetane compounds, and a cyclic compound is 1 to 10 mol per 1 mol of a hydroxyl group. And those obtained by reaction. Here, when the cyclic compound is less than 1 mol per 1 mol of the hydroxyl group, the water resistance and scratch resistance of the cured coating film decrease, and when it exceeds 10 mol, the solvent resistance of the cured coating film decreases. Is not preferred.

The vinyl resin component (b) is a cyclic compound selected from an oxirane compound, a lactone compound and an oxetane compound with respect to 1 mol of the hydroxyl group of the hydroxyl group-containing vinyl monomer. After copolymerizing the compound obtained by ring-opening addition with another vinyl monomer, or copolymerizing a vinyl monomer having a hydroxyl group with another vinyl monomer, The compound can be obtained by ring-opening addition of 1 to 10 mol of a cyclic compound selected from oxirane compounds, lactone compounds and oxetane compounds to 1 mol of hydroxyl groups. Examples of the cyclic compound oxirane compound include, for example, ethylene oxide and propylene oxide.
Examples of the lactone compound include β-methyl-δ-valerolactone, γ-valerolactone, δ-valerolactone, δ-caprolactone, γ-caprolactone, ε-caprolactone, β-propiolactone, γ-butyrolactone, and the like. Examples of the oxetane compound include oxetane and alkylated oxetane.

Examples of the hydroxyl group-containing vinyl monomer include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate and -3-acrylic acid.
Hydroxypropyl, 4-hydroxybutyl acrylate, 6-hydroxyhexyl acrylate, adduct of acrylic acid and glycidyl versatate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, methacrylic acid-3 One or a mixture of two or more of -hydroxypropyl, 4-hydroxybutyl methacrylate, 6-hydroxyhexyl methacrylate, an adduct of methacrylic acid and glycidyl versatate, and the like. As other vinyl monomers, for example, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, t-butyl acrylate , Hexyl acrylate, cyclohexyl acrylate,
2-ethylhexyl acrylate, octyl acrylate,
Lauryl acrylate, stearyl acrylate, isobornyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, t-methacrylate Butyl, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, lauryl methacrylate, stearyl methacrylate, isobornyl methacrylate, acrylic acid, methacrylic acid, trimethoxysilyl acrylate, trimethoxysilyl methacrylate Propyl, perfluoroalkyl acrylate, perfluoroalkyl methacrylate, adamantyl acrylate, adamantyl methacrylate, Jill, glycidyl methacrylate,
Benzyl acrylate, benzyl methacrylate, phenyl acrylate, phenyl methacrylate, -N-acrylic acid
Dimethylaminoethyl, N-dimethylaminoethyl methacrylate, maleic anhydride, itaconic anhydride, maleic ester, fumaric ester, styrene, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, trimethoxypropyl acrylate, methacrylic acid One or a mixture of two or more of trimethoxypropyl, vinyl acetate and the like can be mentioned. Such a vinyl monomer can be made into a copolymer by ordinary radical solution polymerization using a conventional polymerization initiator, for example, an organic peroxide or an azo compound.

As the radical polymerization initiator, for example, 2,
2'-azobisisobutyronitrile, 2,2'-azobis-2,4-dimethylvaleronitrile, 4,4'-azobis-4-cyanovaleric acid, 1-azobis-1-cyclohexanecarbonitrile, dimethyl- Azo compounds such as 2,2'-azobisisobutyrate, methyl ethyl ketone peroxide, cyclohexanone peroxide, 3,5,5-trimethylhexanone peroxide, 1,1-bis (t-butylperoxy) -3,3,5-trimethyl Cyclohexane, 1,1-bis (t-butylperoxy) -cyclohexane, 2,2-bis (t-butylperoxy) octane,
t-butyl hydroperoxide, diisopropylbenzene hydroperoxide, dicumyl peroxide, t-butylcumyl peroxide, isobutyl peroxide, lauroyl peroxide, benzoyl peroxide, diisopropylperoxydicarbonate, t-butylperoxy 2-ethylhexanoate, t -Butyl peroxy neodecanoate, t-butyl peroxy laurate, t
Organic peroxides such as -butylperoxybenzoate and t-butylperoxysopropyl carbonate. A single radical polymerization initiator may be used,
Alternatively, a plurality of types may be used.

Further, two or more chain-like atomic groups having a hydroxyl group at a terminal obtained by reacting a cyclic compound selected from oxirane compounds, lactone compounds or oxetane compounds with hydroxyl groups are contained in one molecule. The upper limit of the number of such chained atomic groups in one molecule is not particularly limited,
It is preferably 50 or less, particularly preferably 2 to 20. When the number of chain atomic groups is less than 2 in one molecule, the solvent resistance of the cured coating film is undesirably reduced. The hydroxyl value of the component (b) is
30 to 200 mgKOH / g is preferable, and 50 to 150 mgKOH / g is preferable.
mgKOH / g is particularly preferred. Hydroxyl value is 30mgK
If it is less than OH / g, the solvent resistance of the cured coating film tends to decrease. When the hydroxyl value exceeds 200 mgKOH / g,
The weather resistance of the cured coating film tends to decrease. The acid value of the component (b) is preferably from 0 to 50 mgKOH / g, and from 0 to 30 mgKOH / g.
mgKOH / g is particularly preferred. Acid value is 50mgKOH
/ G, the water resistance of the cured coating film tends to decrease. The weight average molecular weight of the component (b) is from 1,000 to 200.
000 is preferable, and 2000 to 100,000 is particularly preferable. If the weight average molecular weight is less than 1,000, the weather resistance of the cured coating film tends to decrease. Weight average molecular weight of 200
If it exceeds 000, the appearance of the cured coating film tends to decrease. The component (b) of the present invention is used in the range of 30 to 90 parts by mass, preferably 35 to 85 parts by mass, more preferably 40 to 80 parts by mass. Here, when the component (b) is less than 30 parts by mass, the weather resistance of the cured coating film is unfavorably reduced, and when it exceeds 90 parts by mass, the solvent resistance of the cured coating film is undesirably reduced. The component (c) used in the present invention is a compound having a hydrolyzable alkoxy group or a hydrolyzable aryloxy group directly bonded to a silicon atom, and represented by the general formula (1)

[0018]

Embedded image (R ¹ ) _n —Si— (OR ² ) _4-n (1) (wherein, R ¹ and R ² are each a hydrogen atom or an alkyl group having 1 to 10 carbon atoms or 6 to 10 carbon atoms) Wherein at least one of R ² is an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms,
A plurality of R ² may be the same or different,
n is 0 or 1. ) And / or a condensate thereof. Preferred specific examples of the organosilicate represented by the general formula (1) include, for example, tetrahydroxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, tetraphenoxysilane, dimethoxydiethoxysilane, methyltrimethoxysilane. Methoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, butyltrimethoxysilane,
Hexyltrimethoxysilane, decyltrimethoxysilane, ethoxytrimethoxysilane, propoxytrimethoxysilane, butoxytrimethoxysilane and the like can be mentioned.

The organosilicate condensate is a branched or linear condensate of the organosilicates represented by the above general formula (1), and has a weight average molecular weight in the range of 200 to 2,000. Certain are preferred, and those in the range of 300-1500 are particularly preferred. Commercially available condensates of organosilicates include M
KC silicate MS51, MS56, MS57, MS5
6S, MS56SB5, ES40, EMS31, BTS
(All trade names, manufactured by Mitsubishi Chemical Corporation), methyl silicate 51, ethyl silicate 40, ethyl silicate 4
0t, ethyl silicate 48 (all trade names, manufactured by Colcoat Co., Ltd.) and ethyl silicates 40 and 45 (both trade names, manufactured by Tama Chemical Industry Co., Ltd.) and the like.
In the present invention, the component (c) is necessary immediately after the formation of the coating film in order to make the surface of the coating film hydrophilic and exhibit a high degree of stain resistance. The component (c) is contained in an amount of 0.01 to 20 parts by mass, preferably 0.05 to 15 parts by mass, and more preferably 0.1 to 20 parts by mass.
It is used in the range of 10 to 10 parts by mass. Here, when the component (c) is less than 0.01 part by mass, it is not preferable because the stain resistance cannot be exhibited, and when it exceeds 20 parts by mass, the water resistance of the cured coating film is undesirably reduced.

The component (d) used in the present invention is a particle component of an inorganic oxide sol. As the inorganic oxide sol, one or a mixture of two or more of aluminum oxide sol, silicon oxide sol, zirconium oxide sol, antimony oxide sol, zinc oxide sol, and titanium oxide sol is selected. It is used when it is desired to maintain the scratch resistance and stain resistance for a longer period of time. Such an inorganic oxide sol is generally often produced as an aqueous dispersion, but it can be used in the overcoat composition of the present invention by inverting it to a desired organic solvent. Preferred organic solvents used are methanol,
Ethanol, n-propanol, isopropanol, n-butanol, isobutanol, pentanol, hexanol, 2-ethylhexanol, alcohol solvents such as cyclohexanol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate , Glycol ether solvents such as diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, methyl amyl ketone , Methyl isoamido It is a ketone-based solvent such as luketone and cyclohexanone. As the phase inversion method, for example, a method of adding a water-soluble organic solvent in an aqueous dispersion and repeating the operation of distilling off water to thereby invert the phase in a desired organic solvent may be used. it can.

The dispersion of the silicon oxide sol can be obtained by a method such as adding silicon tetrahalide to water, adding an acid to an aqueous solution of sodium silicate, or condensing an alkoxysilane compound in water. As commercial products, for example, Snowtex 40, Snowtex O, Snowtex C, Snowtex N, Snowtex IPA-
ST, Snowtex EG-ST, Snowtex XB
A-ST, Snowtex MIBK-ST (all trade names, manufactured by Nissan Chemical Industries, Ltd.), Cataloid S-30
H, Cataloid SI-30, Cataloid SN, Cataroid SA, Oscar 1132, Oscar 1232, Oscar 1332 (all trade names, Catalyst Chemical Industry Co., Ltd.)
Adelite AT30, Adelite AT20N, Adelite AT20A, Adelite AT20Q (all trade names, manufactured by Asahi Denka Kogyo Co., Ltd.), Silica Doll 30, Silica Doll 20A, Silica Doll 20B (all trade names, Nippon Chemical Industry ( Alumina sol 100, alumina sol 200, alumina sol 520 (all trade names, manufactured by Nissan Chemical Industries, Ltd.), alumina clear sol, aluminum sol 10, aluminum sol 2
0, aluminum sol SV102, aluminum sol SH5, aluminum sol CSA55, aluminum sol CSA11AD (all trade names, manufactured by Kawaken Fine Chemical Co., Ltd.), etc .; A-1150, A-2550, sun colloid ATL130, sun colloid AMT-130 ( Both can be obtained as antimony oxide sols such as trade names, manufactured by Nissan Chemical Industry Co., Ltd .; zirconium oxide sols, such as NZS-30A, NZS-30B (both trade names, manufactured by Nissan Chemical Industry Co., Ltd.). it can.

The particle component of the inorganic oxide sol is as follows:
By performing a coupling treatment with a silane coupling agent such as γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, methyltrimethoxysilane, the component (a) It may be used in a form in which compatibility with the component (b) is enhanced. The component (d) of the present invention comprises:
It is used in the range of 0 to 30 parts by mass, preferably 3 to 20 parts by mass, more preferably 5 to 15 parts by mass. Here, when the amount of the component (d) exceeds 30 parts by mass, the flexibility of the cured coating film decreases, which is not preferable. The stain-resistant coating composition of the present invention, as it is, or as needed, acrylic resin, polyester resin, other resin such as fluororesin, coloring pigment, bright pigment, filler, solvent, ultraviolet absorber, radical scavenger , Antioxidants, anti-armpit agents, surface conditioners,
An anti-sagging agent, a fluidity adjusting agent, a curing catalyst, a surfactant antistatic agent, a fragrance and the like can also be added.

The top coating composition of the present invention comprises a solvent-free coating composition,
It can be used preferably in a solvent-based state. When used in a solvent-free or solvent-based state, the water content is preferably 5% by mass or less, particularly preferably 2% by mass or less. Suitable solvents include n-hexane, cyclohexane, methylcyclohexane, ethylcyclohexane, terpenes, aliphatic hydrocarbon solvents such as aliphatic naphtha, benzene, toluene, xylene, ethylbenzene, cumene, aromatic hydrocarbons such as aromatic naphtha Solvent, ethyl acetate, propyl acetate, acetic acid n
-Butyl, isobutyl acetate, n-pentyl acetate, n-acetic acid
And carboxylic acid esters such as -hexyl.
Further, an organic solvent used at the time of phase conversion of the component (d) can also be suitably used. The temperature and time required for curing the top coating composition of the present invention are not particularly limited. For example, curing is completed by drying at a temperature in the range of room temperature to 300 ° C. for about 10 seconds to 1 week. I do.

The topcoat composition of the present invention is used as a topcoat for use in a method for preparing an article having a single-layer topcoat or a multilayered coating (composite coating) composed of a colored base coat and a clear topcoat. It can be used, for example, paints for automobiles and other road vehicles, paints for road materials, paints for construction materials, paints for structures, paints for outdoor articles,
It can be used for marine paints, railway paints, aircraft paints, resin material paints, and the like. When used in these paints, the pigment can be blended in an amount of from 0 to 200 parts by mass per 100 parts by mass of all the non-volatile components of the components (a) to (d). It is preferable to mix parts by mass. As the pigment, organic pigments, inorganic pigments, metal pigments, and other pigments used in ordinary paints such as plastic pigments can be used without any limitation. Examples of the composite coating film include, for example, applying a colored film-forming composition on a substrate to form a base coat film, and then forming a clear film-forming composition, which is the top coating composition of the present invention, on the base coat film. Is applied. At this time, the colored film-forming composition may be in any of a solvent-based or water-based form. Furthermore, after applying the colored film-forming composition, it is possible to apply the clear film-forming composition, which is the top coating composition of the present invention, after heating and curing, or after applying the colored film-forming composition. Alternatively, it is also possible to apply the clear film-forming composition, which is the top coating composition of the present invention, without curing, and to cure two layers simultaneously. Furthermore, the topcoat composition of the present invention can be used as an overcoat clear on a coating film that has already been completed up to the topcoat.

The film thickness of the coating film formed by applying the top coating composition of the present invention is not limited at all, and may be, for example, air sprayed so as to be in the range of 1 to 100 μm, usually 10 to 50 μm. The coating is performed using a conventional coating machine such as airless spray, electrostatic air spray, electrostatic rotary atomization coating, dip coating, and roll coating. Examples of the coated article obtained by applying the top coating composition of the present invention include structures, wooden products, metal products, plastic products, rubber products, processed paper, ceramic products, glass products, and the like. More specifically, automobiles, metal plates such as steel plates,
Examples include resin parts for automobiles, motorcycles, ships, railway vehicles, aircraft, furniture, musical instruments, home appliances, building materials, containers, office supplies, sporting goods, toys, and the like.

[0026]

EXAMPLES Next, the present invention will be described in more detail with reference to Production Examples, Examples and Comparative Examples, but the present invention is not limited to these Examples. Production Examples 1 to 4 Production of Component (b) Xylene shown in Table 1 was charged into a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a dropping funnel, and the temperature was raised to 140 ° C. Subsequently, a mixture of the monomer and the polymerization initiator shown in Table 1 was dropped at a constant speed from the dropping funnel over 2 hours. After completion of the dropwise addition, the content was cooled to 100 ° C. while maintaining the reflux temperature for 1 hour. After cooling to 100 ° C, Table 1
The indicated polymerization initiator (additional catalyst) was dropped at a constant speed in 30 minutes. Thereafter, when the temperature of 100 ° C. was maintained for 3 hours, the reaction was terminated, and a copolymer B having the properties shown in Table 1 was obtained.
-1 to B-4 solutions were obtained. The unit of each component of the dropped component and the additional catalyst in Table 1 is parts by mass.

[0027]

[Table 1]

Note, superscripts in the table mean the following. 1): Trade name, manufactured by Daicel Chemical Industries, Ltd., a vinyl monomer obtained by adding 2 mol of ε-caprolactone to 2-hydroxyethyl methacrylate 2): Trade name, manufactured by Daicel Chemical Industries, Ltd., methacryl Vinyl monomer obtained by adding 4 mol of ε-caprolactone to 2-hydroxyethyl acid 3): Trade name, manufactured by NOF Corporation, methacrylic acid-2-
Vinyl monomer with 4 moles of propylene oxide added to hydroxypropyl

Examples 1 to 6 The components and amounts shown in Table 2 were mixed to prepare clear coatings.

[Table 2]

Note, superscripts in the table mean the following. 1): Trade name, manufactured by Asahi Kasei Corporation, isocyanurate of hexamethylene diisocyanate, nonvolatile content 100
wt% (mixed immediately before painting) 2): Trade name, manufactured by Sumitomo Bayer Urethane Co., Ltd., blocked isocyanate compound solution, non-volatile content 75 wt% 3): Trade name, manufactured by Mitsui Chemicals, Inc., butylated melamine resin solution 4): Trade name, manufactured by Cytec Co., Ltd., tris (methyl butyl mixed alkylated carbonylamino) triazine solution, non-volatile content 50 wt% 5): Trade name, manufactured by Mitsubishi Chemical Corporation, condensate of methyl silicate, Effective component 100 wt% 6): Trade name, manufactured by Colcoat Co., Ltd., condensate of ethyl silicate, active component 100 wt% 7): Trade name, manufactured by Nissan Chemical Industries, Ltd., silica sol dispersion, nonvolatile content 30 wt% 8 ): 10 wt% xylene solution of Tinuvin 900 (trade name) manufactured by Ciba Specialty Chemicals 9): Sanol L (trade name) manufactured by Sankyo Co., Ltd. 292 10
wt% xylene solution 10): Trade name, manufactured by Monsanto, leveling agent

Each of the obtained clear paints was thinner (Solvesso # 100 (trade name, aromatic hydrocarbon manufactured by Esso)).
/ Butyl acetate = 80/20 (mass ratio)) and diluted with Ford cup # 4 so that the outflow time was 23 seconds (20 ° C.). The curing agent of the component (a) in Examples 1 and 2 was mixed immediately before dilution with a thinner, and the mixture was applied within one hour after mixing. Each of the diluted clear paints had a water content of 1% by mass or less. Subsequently, a test plate was prepared by the following method, and the coating film performance was evaluated. In Examples 1 and 2, a primer paint Primac No. 1500 (trade name, Nippon Oil & Fat BA) was applied to a degreased polypropylene plate in advance.
SF Coatings Co., Ltd.) by air spray coating to a dry film thickness of 8 μm, and set at room temperature for 4 minutes.
Subsequently, base coat paint Primac No. 5600 silver metallic (trade name, manufactured by NOF BASF Coatings Co., Ltd.) was applied by air spray coating to a dry film thickness of 15 μm. Then, the mixture was set at room temperature for 3 minutes, and the diluted clear paint of Examples 1 and 2 was dried to a film thickness of 40 μm.
m, set at room temperature for 15 minutes, and then held and dried the test plate at 80 ° C. for 30 minutes. In Examples 3 and 4, the cationic electrodeposition paint Casoguard 200 (trade name, manufactured by BASF) was applied to the mild steel sheet treated with zinc phosphate.
Was electrodeposited to a dry film thickness of 20 μm and baked at 175 ° C. for 25 minutes.
00 middle coat (trade name, manufactured by NOF BASF Coatings Co., Ltd.) was applied by air spray coating to a dry film thickness of 30 μm, and baked at 140 ° C. for 30 minutes. Further, a solvent-type base coat paint Bellcoat No. 6000 silver metallic (Nippon Oil & Fats BASF Coatings Co., Ltd.)
Is spray-coated to a dry film thickness of 15 μm, set at room temperature for 3 minutes, air-coated with the above diluted clear paint, and baked at 140 ° C. for 30 minutes.
A test plate was obtained. Further, in Examples 5 and 6, the cationic electrodeposition paint Casoguard 200 (trade name, manufactured by BASF) was electrodeposited on a zinc phosphate-treated mild steel sheet so as to have a dry film thickness of 20 μm, and baked at 175 ° C. for 25 minutes. Intercoat paint High Epico No.500 middle coat (trade name, NOF B
ASF Coatings Co., Ltd.) was applied by air spray coating to a dry film thickness of 30 μm and baked at 140 ° C. for 30 minutes. Furthermore, water-based base coat paint Aqua BC-3
Silver metallic (manufactured by NOF BASF Coatings Co., Ltd.) is applied by air spraying so as to have a dry film thickness of 15 μm, flashed at 80 ° C. for 3 minutes, and then air-coated with the above diluted clear paint, and applied at 140 ° C. for 30 minutes. Baking was performed to obtain a test plate. Table 3 shows the test results.
In any case, coating film appearance, weather resistance, acid resistance, water resistance,
A coating film excellent in stain resistance, scratch resistance and solvent resistance was obtained.

[0032]

[Table 3]

(1) Coating appearance: The fluorescent lamp image reflected on the test plate was visually judged based on the following criteria. ：: The image of the fluorescent lamp is clearly visible. Δ: The image of the fluorescent lamp is slightly blurred. X: The image of the fluorescent lamp is difficult to see. (2) Weather resistance: 3000 using a sunshine carbon arc lamp accelerated weather resistance tester (JIS K-5400 (1990) 9.8.1).
After the time exposure, the state of the coating film was visually determined. (3) Acid resistance: 0.2 mL of a sulfuric acid aqueous solution having a pH of 3 was placed on a test plate in the form of a spot, heated at 60 ° C. for 1 hour and washed with water, and the degree of occurrence of spots was visually determined based on the following criteria. ：: No stain marks are visible at all. Δ: Some stain marks are visible. ×: Stain marks are clearly visible.

(4) Water resistance: The test plate was placed in warm water of 40 ° C.
After immersion for 40 hours, the state of the coating film was visually determined. (5) Stain resistance: JIS K-5400 (1990)
After exposure for 3 months outdoors according to 9.9 weather resistance, the color of the unwashed surface of the coating film (JIS K-5400 (1990) 7.
4.2 measurement method), and the ΔL value was calculated by subtracting the unexposed L value from the exposed L value, and was determined based on the following criteria. △: Δ value is less than 3 Δ: Δ value is 3 or more and less than 6 ×: ΔL value is 6 or more (6) Scratch resistance: muddy water (JIS Z-890)
1-84 8 kinds of dust / water / neutral detergent = 2/97/1 mass ratio) were applied with a brush, and then the car wash brush was rotated at 150 rpm for 10 seconds with an automobile car washer, and the sample was washed with running water. Wash with. After the above operation was repeated four times, the damage of the test plate was visually determined based on the following criteria. ：: Scratch is hardly visible. Δ: Slight damage is observed. X: The damage is remarkably seen. (7) Solvent resistance: The test piece was immersed in petroleum benzene,
After standing at 24 ° C. for 24 hours, the abnormality of the coating film was visually judged.

Comparative Examples 1 and 2 The components and amounts shown in Table 4 were mixed together to prepare clear coatings. The other components in Table 4 are the same as the other components in Table 2.

[Table 4]

Each of the obtained clears was thinner (Solvesso # 100 (trade name, manufactured by Esso, aromatic hydrocarbon)) /
(Butyl acetate = 80/20 mass ratio) with Ford cup # 4
At 23 ° C. (20 ° C.). Subsequently, test plates were prepared in the same manner as in Examples 3 and 4, and the coating film performance was evaluated. That is, a cationic electrodeposition paint Casogard 200 (trade name, manufactured by BASF) is electrodeposited on a zinc phosphate-treated mild steel sheet so as to have a dry film thickness of 20 μm.
Baking at 25 ° C for 25 minutes,
An o.500 middle coat (trade name, manufactured by NOF BASF Coatings Co., Ltd.) was applied by air spray coating to a dry film thickness of 30 μm, and baked at 140 ° C. for 30 minutes. Further, a solvent-type base coat paint Bellcoat No. 6000 silver metallic (manufactured by NOF BASF Coatings Co., Ltd.) is applied by air spray coating so as to have a dry film thickness of 15 μm, and after setting at room temperature for 3 minutes, the diluted clear paint described above is applied. The test plate was obtained by air spray coating and baking at 140 ° C. for 30 minutes. Table 5 shows the test results. In Comparative Example 1, since the component (c) was not contained, the stain resistance of the coating film was inferior. In Comparative Example 2, the component (b) contained the oxirane compound, the lactone compound or the oxetane compound. And a chain atom group having a hydroxyl group at a terminal obtained by the reaction of a cyclic compound selected from the above with a hydroxyl group was not contained, so that the coating film was poor in water resistance and scratch resistance.

[0037]

[Table 5] 1) to 7): Same as Table 3.

[0038]

The overcoat composition of the present invention has weather resistance,
A coating film having excellent water resistance, chemical resistance, stain resistance, scratch resistance and appearance can be formed.

Continued on the front page F term (reference) 4J038 CG141 CH121 DA141 DA161 DA171 DG261 DG301 DL022 DL032 GA03 GA06 GA07 GA09 GA10 HA216 HA446 JA69 JB36 KA18 LA06 MA07 MA10 MA14 NA03 NA04 NA05 NA11 PA07 PA19 PB02 PB04 PB05 PB07 PC08 PC02 PC02

Claims (7)

[Claims] (1) 10 to 70 parts by mass of a curing agent component having a functional group capable of reacting with a hydroxyl group, and (b) a reaction between a hydroxyl compound and a cyclic compound selected from oxirane compounds, lactone compounds and oxetane compounds. 30 to 90 parts by mass of a resin component having two or more chain atomic groups having a hydroxyl group at the terminal to be obtained, and (c) a compound 0.01 having a hydrolyzable alkoxy group or aryloxy group directly bonded to a silicon atom An overcoating composition comprising from 20 to 20 parts by mass of a nonvolatile component. 2. The top coating composition according to claim 1, further comprising (d) 0.5 to 30 parts by mass of a particle component of the inorganic oxide sol. 3. The top coating composition according to claim 1, wherein the component (a) contains at least one selected from an amino resin, a polyisocyanate compound, a blocked polyisocyanate compound and a carbamate compound. 4. A method according to claim 1, wherein the component (b) comprises a chain atom group having a terminal hydroxyl group obtained by reacting 1 to 10 mol of a cyclic compound selected from oxirane compounds, lactone compounds and oxetane compounds with 1 mol of a hydroxyl group. The topcoat composition according to any one of claims 1 to 3, which is an acrylic resin component containing two or more in the molecule. 5. The component (c) is a compound represented by the general formula (1): ## STR1 ## (R ¹ ) _n -Si- (OR ² ) _4-n (1) wherein R ¹ and R ² are each a hydrogen atom Or an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms, wherein at least one of R ² is an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms,
A plurality of R ² may be the same or different,
n is 0 or 1. 5. The topcoat coating composition according to claim 1, which is an organosilicate represented by the formula (1) and / or a condensate thereof. 6. The component (d) is a particle component of at least one inorganic oxide sol selected from aluminum oxide sol, silicon oxide sol, zirconium oxide sol, antimony oxide sol, zinc oxide sol and titanium oxide sol. The top coat composition according to any one of claims 2 to 5. 7. A coated article obtained by applying the top coating composition according to any one of claims 1 to 6.