JP2000144057A - Coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating composition for coating the surface of a substrate, which does not require a long period of time and high temperature conditions in curing and drying and, simultaneously, excels in durability and weatherability and also shelf stability and curing stability. SOLUTION: This coating composition comprises (a) 0.05-50 pts.wt. polymeric film precursor capable of forming a film containing, as the major component, a polymer having a zirconium atom as the skeleton, (b) 50-99.949 pts.wt. organic solvent, and (c) 0.001-5 pts.wt. water. It is preferred that the reaction of forming a film from the polymeric film precursor is the hydrolytic condensation polymerization reaction of a compound containing a zirconium atom or the partial reaction of the hydrolytic condensation polymerization reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a coating composition for coating a substrate surface.

[0002]

2. Description of the Related Art It is a basic function of a paint to provide durability, weather resistance, stain resistance, impact resistance, etc. by coating the surface of a base material. Is generally superior to a paint containing an organic material as a main component. One use of the paint containing the inorganic material as a main component is as an intermediate layer when a film containing a photocatalyst is formed on the surface of a substrate. It is known that a photocatalyst has properties such as antibacterial property, deodorant property, and antifungal property by a decomposition action utilizing its photoactivity. In addition, as disclosed in PCT / WO96 / 29375, when the photocatalyst-containing layer is formed on the surface of the substrate, the surface of the layer exhibits hydrophilicity in response to photoexcitation of the photocatalyst, whereby the glass, lens, It has been found that effects such as anti-fogging property of transparent members such as mirrors, improvement of visibility securing property, anti-fouling property of object surfaces such as automobile bodies and building materials, easy water washing property, rain washing property and self-cleaning property can be obtained. When a film containing such a photocatalyst is formed on the surface of a substrate, if the substrate is a substance which is easily decomposed by a photocatalyst such as plastic or organic paint, the substrate is prevented from being degraded by the decomposition action. In the case of glass, to prevent the alkali contained in the glass from diffusing into the photocatalyst layer and lowering the photoactivity,
It is also known to provide an intermediate layer between the photocatalyst layer and the substrate in order to improve the uniformity when the photocatalyst layer is difficult to form a uniform film on the substrate surface. .

[0003]

However, as a paint containing the above-mentioned inorganic material as a main component, a conventional amorphous silica or silicone resin (hereinafter referred to as amorphous silica, etc.) has been used.
These amorphous silicas and the like have the following drawbacks. Does amorphous silica take a long time to cure and dry?
Alternatively, a high-temperature heat treatment is required for curing / drying, so that the working time is prolonged, a special device is required for curing / drying, or the method cannot be applied to a substrate that cannot withstand the heat treatment. Amorphous silica or the like is inferior in durability and weather resistance, so that the life of the film may be shortened. In addition, various attempts have been made to improve durability and weather resistance by using a material mainly composed of zirconia atom, titanium atom and alumina atom in addition to silicon atom. The reaction speed at the time of curing was too high, and it was not possible to synthesize a coating material having stable storage stability and curing characteristics. The present invention has been made in view of the above circumstances, does not require long-term or high-temperature conditions for curing and drying, and has excellent durability and weather resistance, and excellent storage stability and curing stability,
It is an object to provide a coating composition for coating a substrate surface.

[0004]

According to the present invention, there is provided a polymer film precursor capable of forming a film containing a polymer containing a zirconium atom as a skeleton as a main component.
(B) 50 to 99.949 parts by weight of an organic solvent, (c) 0.001 to 5 parts by weight of water, and a coating composition for coating a substrate surface. .

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the components of the coating composition of the present invention will be described. Preferred as a polymer film precursor capable of forming a film containing a polymer containing a zirconium atom as a skeleton as a main component in the present invention is a polymer film precursor, wherein the polymer film precursor is a hydrolytic condensation polymerization reaction of a compound containing a zirconium atom. Alternatively, the film is formed by a partial reaction of the hydrolysis-condensation polymerization reaction. In this case, all or a part of the water required for hydrolysis is added as a raw material during the production of the coating composition, and if necessary, the remaining water is absorbed from the air after applying the coating composition to the substrate. Alternatively, it is added to the coating composition before application.

Preferred compounds containing a zirconium atom in the present invention include zirconium tetramethoxide, zirconium tetraethoxide, zirconium tetra-n-propoxide, zirconium tetraisopropoxide, zirconium tetra-n-butoxide, zirconium tetra-t-butoxide, Zirconium tetraoctinate, zirconium tetraacetate, zirconium tetraacetylacetonate, zirconium butoxymonoacetylacetonate, zirconium butoxymonoacetylacetonate bisethylacetate, zirconium isopropoxide monoacetylacetonate, zirconium isopropoxide bisacetylacetonate, Zirconium isopropoxide triacetylacetonate,
Zirconium t-butoxymonoacetylacetonate,
Zirconium alkoxides such as zirconium isopropoxide monobenzoylacetonate, zirconium isopropoxide bisbenzoylacetonate, zirconium isopropoxide tribenzoylacetonate, zirconium acetate, zirconium chelate compounds, zirconium acylate compounds and partial hydrolyzates thereof And partially hydrolyzed polycondensates.

The organic solvent in the present invention is not particularly limited as long as it can stably disperse the polymer film precursor and form a uniform and smooth film on the substrate.
If a material having a boiling point of 200 ° C. or higher is used, it takes a long time to dry and may cause whitening of the film.
It is particularly preferred to use: Examples of preferred organic solvents include methanol, ethanol, n-propanol, isopropanol, t-butanol, isobutanol, n-butanol, 2-methylpropanol, pentanol, ethylene glycol, diacetone alcohol, ethylene glycol monomethyl ether, Hydroxy-4-methyl-2-pentanone, dipropylene glycol, propylene glycol, tripropylene glycol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-propoxy-2-propanol, propylene glycol monomethyl ether, Such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, and 2-butoxyethanol; Over and Le solvents, n- hexane, toluene, xylene, hydrocarbon solvents such as mineral spirits, methyl acetate, ethyl acetate, an ester solvent such as butyl acetate.

The weight ratio of the polymer film precursor, organic solvent and water is 0.05 to 50:50 to 99.94.
9: 0.001 to 5 is preferred. In addition, the weight ratio here means the weight ratio as a raw material,
For example, some or all of the water in the coating composition may be consumed for hydrolysis. When the ratio of the polymer film precursor is smaller than the lower limit or the ratio of the organic solvent is larger than the upper limit, it is difficult to form a uniform film, and the ratio of the polymer film precursor is larger than the upper limit or the ratio of the organic solvent is smaller than the lower limit. And the coating composition becomes viscous and uniform application becomes difficult. More preferably, the ratio of the polymer film precursor is 0.1 to 5 parts by weight, more preferably 0.3 to 100 parts by weight of the whole coating composition.
-5 parts by weight. Still more preferably, the ratio of the organic solvent is 95 to 100 parts by weight of the whole coating composition.
99.9 parts by weight, even more preferably 95-9 parts by weight
9.7 parts by weight. If the ratio of water is smaller than the lower limit, the coating composition cannot form a stable coating film. If the ratio is larger than the upper limit, the storage stability of the coating composition is impaired, such as precipitation of the coating composition.
A more preferred water ratio is 1 for the entire coating composition.
It is 0.01 to 0.5 parts by weight as 00 parts by weight.

The skeleton of the polymer contains a silicon atom in addition to the zirconium atom, so that the curing stability can be improved. In this case, a preferable polymer film precursor is one in which the polymer film precursor forms the film by a hydrolytic condensation polymerization reaction of a compound containing a zirconium atom and a compound containing a silicon atom or a partial reaction thereof. . Preferred compounds containing a silicon atom in the present invention include compounds represented by the general formula R _p SiX _4-p (where R is one or more selected from the group consisting of a hydrogen atom and an organic group, and X is One or two or more selected from the group consisting of an alkoxy group and a halogen atom, and p is 1 or 2) can be mentioned.

Preferred examples of the hydrolyzable silane derivative include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, and ethyltripropoxysilane. ,
Ethyl tributoxy silane, phenyl trimethoxy silane, phenyl triethoxy silane, phenyl tripropoxy silane, phenyl tributoxy silane, dimethyl dimethoxy silane, dimethyl diethoxy silane, dimethyl dipropoxy silane, dimethyl dibutoxy silane, diethyl dimethoxy silane, diethyl di Ethoxysilane, diethyldipropoxysilane, diethyldibutoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, phenylmethyldipropoxysilane, phenylmethyldibutoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane,
n-propyltripropoxysilane, n-propyltributoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, octadecyltriethoxysilane, vinyltriethoxysilane , Γ-aminopropyltrimethoxysilane, N-β
(Aminoethyl) γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, β-
(3,4 epoxycyclohexyl) ethyltrimethoxysilane and the like.

In the present invention, other preferable compounds containing a silicon atom include partial hydrolysis and dehydration-condensation polymerization of the above-mentioned hydrolyzable silane derivative, or a partial hydrolyzate of the above-mentioned hydrolyzable silane derivative, Those prepared by dehydration-condensation polymerization with a partial hydrolyzate such as methoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, and diethoxydimethysilane can be used.

The siloxane obtained by the partial hydrolysis / dehydration condensation polymerization is represented by the following average composition formula. R _p SiX _q O _{(4-pq) / 2} (wherein R is one or more selected from the group consisting of a hydrogen atom and an organic group, and X is a group consisting of an alkoxy group or a halogen atom. One or more than one is selected,
p is a number that satisfies 0 <p <2, and q is a number that satisfies 0 <q <4).

Further, another preferred compound containing a silicon atom in the present invention is represented by the general formula SiX ₄ (where X is one or more selected from the group consisting of an alkoxy group or a halogen atom). And a tetrafunctional hydrolyzable silane derivative.

Preferred specific examples of the tetrafunctional hydrolyzable silane derivative include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, diethoxydimethoxysilane, tetrachlorosilane, tetrabromosilane, silanol, dimethoxydimethoxysilane. Ethoxysilane and the like can be mentioned. Further, as another preferred compound containing a silicon atom in the present invention, a partially hydrolyzed and dehydrated polycondensate of the above-mentioned tetrafunctional hydrolyzable silane derivative can be mentioned.

The silicate obtained by the above partial hydrolysis / dehydration condensation polymerization is represented by the following average composition formula. SiX _q O _{(4-q) / 2} (where X is one or more selected from the group consisting of an alkoxy group and a halogen atom, and q is a number satisfying 0 <q <4) ). The addition amount of the compound containing a silicon atom is based on 1 part by weight of the compound containing a zirconium atom.
The amount is preferably 0.01 to 2 parts by weight, and if the amount is more than the upper limit, the curing rate of the coating composition may be slowed or the stability of the coating composition may be impaired. If the amount is less than the above, the film formability may be deteriorated, or the effect of the addition of the compound containing a silicon atom may not be sufficiently exerted. A more preferable addition amount of the compound containing a silicon atom is 0.1 to 2 parts by weight based on 1 part by weight of the compound containing a zirconium atom. Further, a hydrolysis regulator can be added to the coating composition of the present invention in order to improve the storage stability and the curing stability of the coating composition.

Preferred examples of the hydrolysis regulator include alkylamines such as methylamine, ethylamine and laurylamine; amines such as monoalkanolamine, dialkanolamine, trialkanolamine and ethylenediamine; β-diketone compounds such as acetylacetone; Examples include β-ketoester compounds such as ethyl acetate, α-diols, β-diols, ethylene glycol, propylene glycol, other glycol derivatives, acetic acid, p-toluenesulfonic acid, ammonia, and ammonium acetate. Particularly preferred hydrolysis regulators include ammonium acetate. The preferable content of the hydrolysis regulator is 0.001 to 10 parts by weight based on 100 parts by weight of the whole coating composition. If the content of the hydrolysis modifier is larger than the upper limit, the coating composition may become unstable, whereas if it is smaller than the lower limit, the effect of addition may not be sufficiently exhibited. A more preferred content of the hydrolysis regulator is 0.001 to 2 parts by weight based on 100 parts by weight of the whole coating composition.

The atoms capable of forming a polymer skeleton other than zirconium and silicon include titanium, aluminum, boron, germanium, tin, zinc, gallium, and the like.
Indium and the like can be mentioned, and a compound containing these atoms can be added as a raw material of the coating composition of the present invention. Further, as a curing catalyst for the coating composition of the present invention, alkyl titanate, tin octylate,
Metal salts of carboxylic acids such as dibutyltin dilaurate, dioctyltin dimaleate, amine salts such as dibutylamine-2-hexoate, dimethylamine acetate, ethanolamine acetate, tetraethylpentamine, monoethanolamine, N, N-dimethylbenzylamine
Amines such as hexylamine, tributylamine, ethylenediamine, hexanediamine, diethylenetriamine and triethylenetetramine; amine-based silane coupling materials such as N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane; P-toluenesulfonic acid Acids such as phthalic acid, acetic acid, hydrochloric acid, nitric acid, sulfuric acid, propionic acid, maleic acid, adipic acid, fumaric acid, valeric acid, lactic acid, butyric acid, citric acid, malic acid, picric acid, formic acid, and carbonic acid, aluminum chelate Aluminum compounds such as aluminum, aluminum acetylacetonate, aluminum perchlorate, aluminum chloride, aluminum isobutoxide, aluminum isopropoxide; titanium compounds such as tetraisopropyl titanate and tetrabutyl titanate; Lithium, sodium hydroxide, potassium hydroxide, sodium methylate, sodium acetate, sodium formate, potassium acetate, potassium formate, potassium propionate, tetramethylammonium chloride, tetramethylammonium hydroxide,
Basic compounds such as ammonia; tin compounds such as tin acetylacetonate and dibutyltin octylate; cobalt octylate, cobalt acetylacetonate;
Metal-containing compounds such as iron acetylacetonate can also be added.

Further, as a leveling agent of the coating composition in the present invention, diacetone alcohol, ethylene glycol monomethyl ether, 4-hydroxy-4
-Methyl-2-pentanone, dipropylene glycol,
Tripropylene glycol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, propylene glycol monomethyl ether, 1-propoxy-2-
It is also possible to add propanol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monoethyl ether, acetylene alcohol, and the like. The addition of a leveling agent is particularly advantageous when applying the composition according to the invention to large articles.

In the coating composition of the present invention, as a surfactant, a polyoxyethylene alkylphenyl ether ammonium sulfonate, a sodium salt of polyoxyethylene alkylphenyl ether sulfonate, a sodium soap of a fatty acid, a potassium soap of a fatty acid,
Sodium dioctyl sulfosuccinate, alkyl sulfate, alkyl ether sulfate, alkyl sulfate soda salt, alkyl ether sulfate soda salt, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl ether sulfate soda salt, alkyl sulfate TEA salt, polyoxyethylene alkyl ether sulfate TEA salt, 2-
Ethylhexyl alkyl sulfate sodium salt, sodium acylmethyltaurate, sodium lauroylmethyltaurate, sodium dodelsylbenzenesulfonate, disodium lauryl sulfosuccinate, disodium lauryl polyoxyethylene sulfosuccinate,
Polycarboxylic acid, oleoyl sarcosine, amide ether sulfate, lauroyl sarcosine, sulfo F
Anionic surfactants such as sodium salt of A ester; polyoxyethylene lauryl ether, polyoxyethylene tridecyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene alkyl ether, polyoxyethylene Oxyethylene alkyl ester, polyoxyethylene alkyl phenol ether,
Polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene laurate, polyoxyethylene stearate, polyoxyethylene alkyl phenyl ether, polyoxyethylene oleate, sorbitan alkyl ester,
Polyoxyethylene sorbitan alkyl ester, polyether modified silicone, polyester modified silicone, sorbitan laurate, sorbitan stearate,
Sorbitan palmitate, sorbitan oleate, sorbitan sesquioleate, polyoxyethylene sorbitan laurate, polyoxyeletin sorbitan stearate, polyoxyethylene sorbitan palmitate, polyoxyethylene sorbitan oleate, glycerol stearate, polyglycerin fatty acid ester , Alkylalkylolamide, lauric acid diethanolamide, oleic acid diethanolamide, oxyethylene dodecylamine, polyoxyethylene dodecylamine, polyoxyethylene alkylamine, polyoxyethylene octadecylamine, polyoxyethylene alkylpropylenediamine, polyoxyethyleneoxy Nonionic surfactants such as propylene block polymer and polyoxyethylene stearate Agent; dimethyl alkyl betaine,
Amphoteric surfactants such as alkylglycine, amidobetaine and imidazoline, octadecyldimethylbenzylammonium chloride, alkyldimethylbenzylammonium chloride, tetradecyldimethylbenzylammonium chloride, dioleyldimethylammonium chloride, 1-hydroxyethyl-2-alkylimidazoline quaternary Salt, alkylisoquinolinium bromide,
Polymeric amine, octadecyltrimethylammonium chloride, alkyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, behenyltrimethylammonium chloride, alkylimidazoline quaternary salt, dialkyldimethylammonium chloride, octadecylamine acetate, tetradecylamine acetate Cationic surfactants such as salts, alkyl propylene diamine acetate, and didecyl dimethyl ammonium chloride can also be added.

In addition, the coating composition according to the present invention may contain, as additives, fillers such as silica, alumina, talc, clay and calcium carbonate; thickeners such as polyethylene glycol and cellulose; coloring agents such as iron oxide; An antioxidant such as hydroxytoluene and butylhydroxyanisole can also be used. Further, an ultraviolet absorber and a radical scavenger for paint can be added.

The method of applying the coating composition of the present invention to the surface of a substrate may be appropriately selected. Examples thereof include a spray coating method using an air gun, an airless gun, an aerosol spray, etc., a dip coating method, a flow coating method, and a spin coating method. Method, roll coating method, brush coating, sponge coating and the like can be suitably used.

The preferable coating amount of the coating composition on the surface of the base material is 0.005 to 0.1 kg / m ² in terms of the weight per unit area of the base material. If it is larger, a uniform coating film may not be formed. A more preferable application amount is 0.001 to 0.01 k in the case of applying with a brush, a sponge, a cloth, or the like.
g / m ² , and in the case of spray application, 0.01 to 0.1 g / m ² .
It is 1 kg / m ² . After being applied to the substrate surface, the coating composition is dried or cured to form a thin film. In the present invention, drying or curing means that a compound containing a zirconium atom or the like forms a polymer containing a zirconium atom or the like as a skeleton by a hydrolysis-condensation polymerization reaction or a partial reaction thereof while the organic solvent is evaporated. It is. Therefore, drying or curing may be performed by any means such as natural drying, heating, infrared irradiation and ultraviolet irradiation.
From the viewpoint that a special apparatus is not required for drying, it is preferable that heating is performed at a temperature of 80 ° C. or less, and it is more preferable to employ a means of air drying. In the coating composition of the present invention, a compound containing a zirconium atom is mainly used. This can be achieved by using it as a component. However, the coating composition of the present invention is at 80 ° C.
Even if it is to be dried and cured by the following heating or natural drying, if drying and curing are required to be very short or if the durability of the coating film is large,
Heating at a temperature of 80 ° C. or more may be performed.

The curing time of the coating composition in the present invention is desirably as short as possible in order to increase the working efficiency. The curing time as used herein does not necessarily mean the time until all the hydrolysis-condensation polymerization reactions are completed, and the time until the coating composition is applied and the coating composition becomes usable, and the top coat layer containing the photocatalyst. When used as an intermediate layer, it is a time until the top coat layer can be applied, and in the present invention, by using a compound containing a zirconium atom as a main component, the curing time is 5 minutes to 60 minutes by natural drying. Can be shortened. However, even when the coating composition of the present invention is dried and cured in a time period of 5 to 60 minutes by natural drying, it is not required that drying and curing be performed in a short time, If the demand is large, the curing time can be longer than 60 minutes.

The preferable average thickness of the film containing a polymer containing a zirconium atom as a skeleton formed on the substrate in this manner is preferably from 10 nm to 5 μm. If it is larger than the upper limit, the film may become non-uniform, transparency may be impaired, or a defect may occur in appearance. In order to prevent the occurrence of interference fringes, the average thickness of the film is more preferably 0.5 μm to 3 μm or 10 nm to 200 n.
m, and particularly when the thickness is 10 nm to 200 nm, stable coating film performance can be obtained.

When the coating composition of the present invention is used as an intermediate layer for a photocatalyst layer, an optical semiconductor is applied on the intermediate layer formed by applying or drying or curing the coating composition on the surface of a substrate. The containing top coat layer is formed. Preferred as the optical semiconductor are photocatalyst particles containing a metal oxide as a main component, and preferred metal oxides are anatase-type titanium oxide, rutile-type titanium oxide, zinc oxide, tin oxide, ferric oxide, and trioxide. Mention can be made of bismuth, tungsten trioxide, and strontium titanate. The combination of the intermediate layer and the top coat layer causes phenomena such as deterioration of the base material due to the optical activity of the optical semiconductor contained in the top coat layer and decrease in the optical activity of the optical semiconductor due to diffusion of substances such as alkali from the base material. The surface of the base material can be provided with properties such as antibacterial properties, deodorization control, and antifungal properties without occurrence of cracks. The combination of the intermediate layer and the top coat layer is particularly effective for imparting hydrophilicity to the surface of the base material, thereby exhibiting antifogging property, antifouling property, easy water washing property and self-cleaning property.

The type of the substrate to which the present invention can be applied is not limited, and can be applied to substrates of any material. Particularly, when used as an intermediate layer for imparting photocatalytic hydrophilicity to the substrate, Especially for applications where transparent materials such as glass, mirrors, lenses, films, etc. are given anti-fog properties and visibility, and anti-fouling, easy-cleaning and self-cleaning properties are given to the surface of objects such as automobile bodies and building materials. It is valid. In order to take advantage of the characteristic of the coating composition of the present invention that it dries or cures at a low temperature and in a short time, it is effective to apply it to the field of on-site construction, for example, a service station or an automobile constructed by a car owner. As an intermediate layer to impart durability and weather resistance and to impart photocatalytic hydrophilicity by applying it to body and glass of building or to building materials such as window glass and wall materials of existing buildings When it is used, the field of imparting antifouling property and self-cleaning property can be mentioned.

[0027]

EXAMPLES Comparative Example 1 1.7 parts by weight of tetrabutoxyzirconium, 0.5 parts by weight of methyltrimethoxysilane, 0.1 parts by weight of polymethoxypolysiloxane, 1 part by weight of 1-butanol and 1 part by weight of 2-propanol Was mixed with 97.7 parts by weight of a solvent mixture to obtain a coating composition. Example 1 A mixed solvent of 1.7 parts by weight of tetrabutoxyzirconium, 0.5 parts by weight of methyltrimethoxysilane, and 0.1 parts by weight of polymethoxypolysiloxane, 1 part by weight of 1-butanol and 1 part by weight of 2-propanol The mixture was mixed with 97.55 parts by weight, and 0.15 parts by weight of water was added to obtain a coating composition.

When Comparative Example 1 and Example 1 were spray-coated on a black acrylic melamine-based coated steel sheet at 25 g / m ^{2, the} coating of Example 1 was transparent, whereas the coating of Comparative Example was cloudy. . After the coating film of Example 1 was left at room temperature for 15 minutes, a photocatalytic top coat solution (0.2 parts by weight of anatase type titanium oxide having a particle diameter of about 10 nm and 0.2 parts by weight of amorphous silica) was formed thereon. Part, 1-propanol 7
9.68 parts by weight, 19.92 parts by weight of propylene glycol monomethyl ether, nitric acid (about 100 ppm))
5 g / m ^{2 was} spray applied. The appearance of the coating film was transparent and glossy, and a uniform film was obtained. Subsequently, the hydrophilic properties of the coating film were evaluated. The initial contact angle with water was 55 °. After three days of outdoor exposure, when the contact angle with water was measured again, it was reduced to 20 °.

Examples 2 to 11 As shown in Table 1, 0.1% by weight of an additive was added to the coating composition of Example 1.

[0030]

[Table 1]

0.5% by weight of water was added to the obtained composition.
0% by weight of each was added, and the state of the solution was observed with time from immediately after the addition to after standing at 50 ° C. overnight. The results are shown in Table 1. It has been found that these additives improve the stability to water.

Examples 12 to 15 As shown in Table 2, 0.02 to 0.3% by weight of ammonium acetate was added to the coating composition of Example 1.

[0033]

[Table 2]

1.0% by weight of water was added to the obtained composition.
0% by weight of each was added, and the state of the solution was observed with time from immediately after the addition to after standing at 50 ° C. overnight. The results are shown in Table 2. It was found that there was an optimum range for the amount of ammonium acetate added to the coating composition.

Examples 16 to 19

[0036]

[Table 3]

Water was added to the coating compositions shown in Table 3
After 0% by weight was added and left at 50 ° C. overnight, the state of the liquid was observed. The results are shown in Table 3. It was found that the water stability of the coating composition was also affected by the zirconium butoxide / methyltrimethoxysilane ratio.

[0038]

According to the present invention, it is possible to obtain a coating composition for forming a film having excellent storage / curing stability and excellent durability on the surface of a substrate without requiring high-temperature conditions for curing.

Continued on the front page (72) Inventor Masahiro Shibado 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Prefecture Inside Totoki Equipment Co., Ltd. (72) Inventor Masazumi Uematsu 1-1-1 Minamiasama-cho, Nishi-ku, Yokohama-shi, Kanagawa-ken F-term (reference) in Yokohama Yushi Kogyo Co., Ltd. 4J038 DM021 GA15 HA156 HA216 HA246 JA05 JA17 JA25 JA45 JA56 JB01 KA04 KA06 NA03 NA05 NA06 NA25 NA26 PC02 PC03

Claims (16)

[Claims] (1) 0.05 to 50 parts by weight of a polymer film precursor capable of forming a film mainly composed of a polymer containing a zirconium atom as a skeleton; and (b) 50 to 99.949 parts by weight of an organic solvent. (C) A coating composition for coating the surface of a substrate, comprising 0.001 to 5 parts by weight of water. 2. The reaction for forming the film from the polymer film precursor is a hydrolysis-condensation polymerization reaction of a compound containing a zirconium atom or a partial reaction of the hydrolysis-condensation polymerization reaction. The coating composition according to claim 1. 3. The compound containing a zirconium atom includes a zirconium alkoxide, a partially hydrolyzed product of a zirconium alkoxide, a partially hydrolyzed condensation polymer of a zirconium alkoxide, a zirconium chelate compound, a partially hydrolyzed product of a zirconium chelate compound, and a zirconium chelate compound. A partially hydrolyzed condensed polymer, a zirconium acylate compound, a partially hydrolyzed zirconium acylate compound, and a partially hydrolyzed condensed polymer of a zirconium acylate compound. 3. The coating composition according to 2. 4. The coating composition according to claim 1, wherein said skeleton further contains a silicon atom. 5. The reaction for forming the film from the polymer film precursor is a hydrolysis-condensation polymerization reaction of the compound containing a zirconium atom and the compound containing a silicon atom or a part of the hydrolysis-condensation polymerization reaction. The coating composition according to claim 4, which is a reaction. 6. The compound containing a silicon atom is selected from the group consisting of: (a) a compound represented by the general formula R _p SiX _4-p (where R is one or more selected from the group consisting of a hydrogen atom and an organic group) , X is one or more selected from the group consisting of an alkoxy group and a halogen atom, and p is 1 or 2.) (b) Average composition formula R _p SiX _q O _{(4-pq) / 2} (where
R is one or more selected from the group consisting of a hydrogen atom and an organic group; X is one or more selected from the group consisting of an alkoxy group and a halogen atom; A siloxane represented by <p <2 and q is a number satisfying 0 <q <4, respectively. (C) General formula SiX ₄ (wherein X is one of a group consisting of an alkoxy group and a halogen atom or (D) average composition formula SiX _q O _{(4-q) / 2} (where X is an alkoxy group and a halogen atom) One or more members are selected from the group, and q is a number satisfying 0 <q <4). 6. The coating composition according to 5. 7. The content of the compound containing a silicon atom is 0.01 to 1 part by weight of the compound containing a zirconium atom.
The coating composition according to any one of claims 5 to 6, wherein the amount is from 2 to 2 parts by weight. 8. The coating composition according to claim 1, wherein said coating composition further comprises a hydrolysis regulator. 9. The coating composition according to claim 8, wherein said hydrolysis regulator is selected from the group consisting of acids, bases and amines. 10. The coating composition according to claim 8, wherein the hydrolysis modifier is ammonium acetate. 11. The content of the hydrolysis regulator is 0.001 to 10 with respect to 100 parts by weight of the whole coating composition.
The coating composition according to any one of claims 8 to 10, wherein the coating composition is part by weight. 12. The coating composition according to claim 1, wherein said coating composition is a coating composition used for coating a substrate surface and forming a top coat layer containing an optical semiconductor thereon. A coating composition according to claim 1. 13. The coating composition according to claim 12, wherein the optical semiconductor is a photocatalyst particle containing a metal oxide as a main component. 14. The metal oxide is selected from the group consisting of anatase type titanium oxide, rutile type titanium oxide, zinc oxide, tin oxide, ferric oxide, bismuth trioxide, tungsten trioxide, and strontium titanate. The coating composition according to claim 13, wherein 15. The coating composition according to claim 12, wherein said top coat layer exhibits photocatalytic hydrophilicity. 16. The coating composition according to claim 1, wherein the coating composition can be cured at a temperature of 80 ° C. or less, more preferably by natural drying.