JP4324775B2 - Coating composition and structure for undercoating containing photocatalyst coating film - Google Patents

Description

  The present invention relates to a coating composition for undercoat of a photocatalyst-containing coating film, and more specifically, can prevent deterioration of a substrate due to a photocatalyst, and can provide a coating film having high hardness, excellent weather resistance and long-term durability adhesion. The present invention relates to a coating composition suitable for undercoating of a photocatalyst-containing coating film.

  In recent years, coating compositions that are excellent in weather resistance, stain resistance, and chemical resistance and that can form a coating film with high hardness have been demanded, and in the future, highly versatile ones will be demanded. So far, as a composition comprising a silyl group-containing vinyl resin and an organosilane compound, there are Patent Document 1 (Japanese Patent Laid-Open No. 01-69673) and Patent Document 2 (Japanese Patent Laid-Open No. 01-69674). In either case, the base material is limited. Moreover, although there exists patent document 3 (Unexamined-Japanese-Patent No. 04-108172), patent document 4 (Unexamined-Japanese-Patent No. 04-117473), etc., although all the object base materials are wide, it describes concretely about coating specifications. It is not done.

  Meanwhile, organosilane coating materials are being developed as maintenance-free coating materials with excellent weather resistance (light) resistance and contamination resistance. The performance requirements for such organosilane coating materials are becoming stricter. In recent years, coating film appearance, adhesion, weather resistance, heat resistance, alkali resistance, organic chemical resistance, moisture resistance, (temperature) There is a need for a coating material that is excellent in water resistance, insulation resistance, abrasion resistance, stain resistance, and the like and can form a coating film with high hardness.

  In particular, in order to improve the stain resistance, it is recognized that the surface of the coating film should be made hydrophilic. For example, a method of adding a hydrophilic substance or a water-soluble substance has been proposed. However, in such a method, it is difficult to maintain the hydrophilicity of the coating film surface at a sufficient level for a long time because the hydrophilic substance and the water-soluble substance are gradually deteriorated by light or washed away with water. is there.

  In recent years, many coating compositions containing a photocatalytic component have been proposed. Examples thereof include titanium oxides, hydrolysates of hydrolyzable silicon compounds (alkyl silicates or silicon halides), and solvents (water or alcohols). ) A titanium oxide coating film-forming composition for photocatalysts (Patent Document 5: JP-A-8-164334), a silicon compound having at least two alkoxy groups, a titanium compound having at least two alkoxy groups, or zirconium Surface treatment composition for imparting antibacterial and antifungal properties comprising a compound and a hydrophilic inorganic powder such as titanium oxide treated with alkoxysilane and / or polysiloxane having a guanidyl group (Patent Document 6: No. 8-176527), tetraalkoxysilane 2 ~ 200 parts by weight, trialkoxysilane 100 parts by weight and dialkoxysilane 0-60 parts by weight, mixing of an inorganic paint having a polystyrene equivalent weight average molecular weight of 900 or more prepared from the raw material and a powder having a photocatalytic function A method for forming an inorganic coating film (Patent Document 7: JP-A-8-259891) in which a coating film obtained from a solution is treated with an acid or an alkali is known.

  However, these coating-forming compositions and liquid mixtures are intended to be antibacterial / antifungal, deodorizing and decomposing harmful substances based essentially on the photocatalyst component or alkoxysilane and / or polysiloxane component having a guanidyl group. In addition to these functions, the coating performance including the hardness, adhesion, alkali resistance, organic chemical resistance, weather resistance, and contamination resistance required for organosilane coating materials is comprehensively studied. It has not been done.

  On the other hand, as a coating composition that satisfies the required performance for the organosilane coating material to some extent, a composition comprising an organosilane partial condensate, a colloidal silica dispersion, and a silicone-modified acrylic resin (Patent Document 8: JP-A-60) -135465), a condensate of organosilane, a chelate compound of zirconium alkoxide and a hydrolyzable silyl group-containing vinyl resin (Patent Document 9: Japanese Patent Laid-Open No. 64-1769), A composition in which a condensate, colloidal alumina, and a hydrolyzable silyl group-containing vinyl resin are arranged (Patent Document 10: US Pat. No. 4,904,721) and the like have been proposed.

  However, the coating film obtained from the composition described in Patent Document 8 (JP-A-60-135465) and Patent Document 10 (US Pat. No. 4,904,721) has a long time. There is a drawback that the gloss is lowered by ultraviolet irradiation. In addition, the composition described in Patent Document 9 (Japanese Patent Application Laid-Open No. 64-1769) has a problem that storage stability is not sufficient, and if the solid content concentration is increased, gelation is likely to occur in a short period of time. is doing.

  Further, the applicant of the present patent application has already obtained a hydrolyzate of organosilane and / or a partial condensate thereof, a hydrolyzable and / or vinyl-based resin having a silyl group having a silicon atom bonded to a hydroxyl group, a metal chelate compound, and β Has proposed a coating composition (Patent Document 11: JP-A-5-345877) containing a diketone and / or a β-ketoester, and the composition is required for an organosilane coating material. Although it is excellent in the balance of the coating film performance, further improvement is demanded for these performances.

By the way, when the coating composition containing the photocatalyst component as described above is directly applied to the base material, when the substrate is an organic substance such as plastic, the base material itself is likely to deteriorate due to the oxidation action of the photocatalyst. There is a problem that it is inferior in weather resistance and durability adhesion. In addition, when the substrate is an inorganic substance such as glass or metal, there are problems such as a decrease in photocatalytic ability due to migration of metal ions and poor adhesion. Furthermore, even when the base is preliminarily coated, the adhesion between the topcoat layer (photocatalyst layer) and the substrate may be insufficient.
Further, as an undercoating coating composition dedicated to a photocatalyst, there is Patent Document 12 (Patent No. 3038599), but when applied to an organic substrate that is particularly required to be flexible, the radical degradation resistance to a photocatalyst-containing coating film, In some cases, the long-term adhesion to the organic substrate cannot be balanced.

Japanese Patent Laid-Open No. 01-69673 Japanese Patent Laid-Open No. 01-69694 Japanese Patent Laid-Open No. 04-108172 Japanese Patent Laid-Open No. 04-117473 JP-A-8-164334 JP-A-8-176527 Japanese Patent Laid-Open No. 8-259891 JP-A-60-135465 JP-A 64-1769 U.S. Pat. No. 4,904,721 JP-A-5-345877 Japanese Patent No. 3038599

  The present invention can satisfy the conflicting demands of adhesion to organic substrates (organic properties) and radical degradation resistance (inorganic properties) to photocatalysts. An object of the present invention is to provide a coating composition that improves adhesion, is excellent in adhesion to a substrate, has long-term durability without impairing the photocatalytic ability of the overcoat layer, and is useful as an undercoat for a photocatalyst-containing coating film. And

In the presence of (b) a polymer containing a silyl group having a silicon atom bonded to a hydrolyzable group and / or a hydroxyl group (hereinafter also referred to as “(b) silyl group-containing polymer”),
(A) The following general formula (1)
(R ¹ ) _n Si (OR ² ) _4-n (1)
(In the formula, when two R ¹ are present, they are the same or different and each represents a monovalent organic group having 1 to 8 carbon atoms; R ² is the same or different and is an alkyl group having 1 to 5 carbon atoms or 1 carbon atom; At least one selected from the group consisting of an organosilane represented by -6, n being an integer of 0 to 2, a hydrolyzate of the organosilane, and a condensate of the organosilane
An organic-inorganic hybrid polymer that has been previously hydrolyzed / condensed, and (c) an average composition formula R ³ _p Si (OR ⁴ ) _q O _{(4-pq) / 2} (wherein R ³ has 1 to 18 carbon atoms ₎ Wherein R ⁴ is a hydrogen group or one or more of monovalent organic groups having 1 to 4 carbon atoms, and p and q is a number satisfying 0 ≦ p ≦ 1.8, 0 <q <3.3, 0 <p + q <4) (hereinafter also referred to as “(c) siloxane oligomer”)
The present invention relates to a coating composition for undercoating containing a photocatalyst containing coating (hereinafter also referred to as “coating composition” or “composition (I)”) .
In this case, the organic-inorganic hybrid polymer obtained from the component (a) and the component (b) has a weight ratio of (a) component (completely hydrolyzed condensate) / (b) component of 5/95 to 60/40 . is there.
Moreover, the siloxane oligomer which is 0 <= p <= 1 in the average compositional formula of the said (c) component is preferably used as an oligomer obtained from a tetrafunctional / 3 functional / 2 functional silane derivative.
Furthermore, the siloxane oligomer which consists of 1 type or 2 types or more of the siloxane oligomer which is p = 0 or 1 in the average composition formula of the said (c) component is preferably used as a tetrafunctional oligomer and / or a trifunctional oligomer.
Furthermore, in the average composition formula of the component (c), R ⁴ is one or more monovalent organic groups having 1 to ⁴ carbon atoms. Adhesiveness) and radical degradation resistance (undercoat layer / adhesiveness between photocatalyst-containing coating films) are preferred from the standpoint of compatibility.
The coating composition of the present invention may further contain (f) an inorganic filler.
The coating composition of the present invention may further contain (g) an ultraviolet absorber.
The coating composition of the present invention is a photocatalyst-containing coating composition used when forming an upper layer photocatalyst-containing coating film, which is produced from water-dispersed titanium oxide having an average particle size of 0.2 μm or less as a raw material. It may be applied in some cases.
In the coating composition of the present invention, the photocatalyst-containing coating composition used when forming the upper-layer photocatalyst-containing coating film was produced using a titanium oxide powder having an average particle size of 0.2 μm or less, or a titanium alkoxide as a raw material. The photocatalyst-containing coating composition containing 1% by weight or more of water based on the solid content of titanium oxide may be used.
Next, in the present invention, a coating film obtained from the coating composition for undercoating of the above-described photocatalyst-containing coating film of the present invention is provided on a substrate, and a coating film made of the photocatalytic coating composition containing water is formed thereon. Related to the structure.

  The coating composition of the present invention can satisfy the conflicting requirements of adhesion to organic substrates (organic properties) and radical degradation resistance (inorganic properties) to photocatalysts, can prevent degradation of the substrate due to photocatalysts, and weather resistance It is possible to obtain a cured product having excellent properties and excellent adhesion to the substrate and the photocatalyst layer.

In the coating composition of the present invention, the component (c), which is a siloxane oligomer, is added afterwards to suppress condensation reactivity at the time of curing the intermediate layer (undercoat layer) between the photocatalyst-containing coating film and the base material layer, Adhesion to the base material layer can be ensured, and the siloxane oligomer can be hydrolyzed and condensed during coating of the overcoat layer (photocatalyst-containing layer) to ensure adhesion with the overcoat layer.
The coating composition of the present invention can satisfy the conflicting requirements of adhesion to organic substrates (organic properties) and radical degradation resistance (inorganic properties) to photocatalysts, and has high hardness, weather resistance, and oxidation resistance. As an excellent coating composition for the undercoat of a photocatalyst-containing coating film, it has an excellent effect of improving the adhesion between the topcoat layer (photocatalyst-containing coating film) and the substrate and having excellent long-term durability by containing many silanol groups. Useful.
The coating composition of the present invention may be applied to a substrate a plurality of times, or another primer coating composition may be applied between the coating composition of the present invention and the substrate. May be used.
Hereinafter, the coating composition of the present invention will be described, and then the photocatalyst-containing coating film will also be described.

Coating composition of the present invention The coating composition of the present invention comprises as a main component an organic-inorganic hybrid polymer obtained by co-condensing the component (a) and the component (b) , and (c) a siloxane oligomer.
(A) component;
The component (a) is composed of an organosilane represented by the general formula (1) (hereinafter referred to as “organosilane (1)”), a hydrolyzate of organosilane (1), and a condensate of organosilane (1). At least one selected. That is, the component (a) may be only one of these three types, a mixture of any two types, or a mixture including all three types. Here, in the hydrolyzate of the organosilane (1), it is not necessary that all ² to 4 OR ² groups contained in the organosilane (1) are hydrolyzed. For example, only one hydrolyzate is hydrolyzed. Or two or more of them may be hydrolyzed, or a mixture thereof. Moreover, the condensate of the organosilane (1) is a product in which the silanol group of the hydrolyzate of the organosilane (1) is condensed to form a Si—O—Si bond. It is not necessary to condense all of them, and it is a concept including a mixture of a small part of silanol groups or a mixture of those having different degrees of condensation.

In the general formula (1), examples of the monovalent organic group having 1 to 8 carbon atoms of R ¹ include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, and an i-butyl group. Group, sec-butyl group, t-butyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group and other alkyl groups; acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group Acyl groups such as trioyl group and caproyl group; vinyl group, allyl group, cyclohexyl group, phenyl group, epoxy group, glycidyl group, (meth) acryloxy group, ureido group, amide group, fluoroacetamide group, isocyanate group, etc. In addition to these, substituted derivatives of these groups can be mentioned.

Examples of the substituent in the substituted derivative of R ¹ include a halogen atom, a substituted or unsubstituted amino group, a hydroxyl group, a mercapto group, an isocyanate group, a glycidoxy group, a 3,4-epoxycyclohexyl group, and a (meth) acryloxy group. Ureido group, ammonium base and the like. However, the carbon number of R ¹ composed of these substituted derivatives is 8 or less including the carbon atom in the substituent. In the general formula (1), when two R ^{1 s} are present, they may be the same as or different from each other.

Examples of the alkyl group having 1 to 5 carbon atoms of R ² include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, and n. -A pentyl group etc. can be mentioned, As a C1-C6 acyl group, an acetyl group, a propionyl group, a butyryl group, a valeryl group, a caproyl group etc. can be mentioned, for example.
A plurality of R ² present in the general formula (1) may be the same as or different from each other.

  Specific examples of such organosilane (1) include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, and tetra-n-butoxysilane; methyl Trimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, n-butyl Trimethoxysilane, n-butyltriethoxysilane, n-pentyltrimethoxysilane, n-hexyltrimethoxysilane, n-heptyltrimethoxysilane, n-octyltrimethoxysilane, vinyltrimethoxysilane, vinyltri Toxisilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane 3,3,3-trifluoropropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-hydroxyethyltrimethoxysilane, 2-hydroxyethyltriethoxysilane, 2-hydroxypropyl Trimethoxysilane, 2-hydroxypropyltriethoxysilane, 3-hydroxypropyltrimethoxysilane, 3-hydroxypropyltriethoxysilane, 3-mercaptopropyl Limethoxysilane, 3-mercaptopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) attaacryloxy Trialkoxysilanes such as propyltriethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane; dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, di Ethyldiethoxysilane, di-n-propyldimethoxysilane, di-n-propyldiethoxysilane, di-i-propyldimethoxysilane, di-i-propyldiethoxysilane, di-n-butyldimethoxysilane, di-n -Butyldiethoxysilane, di-n-pentyldimethoxysilane, di-n-pentyldiethoxysilane, di-n-hexyldimethoxysilane, di-n-hexyldiethoxysilane, di-n-heptyldimethoxysilane, di- n-heptyldiethoxysilane, di-n-octyldimethoxysilane, di-n-octyldiethoxysilane, di-n-cyclohexyldimethoxysilane, di-n-cyclohexyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, etc. In addition to dialkoxysilanes Triacetyl silane, and the like dimethyl acetyloxy silane.

  Of these, trialkoxysilanes and dialkoxysilanes are preferable, and as the trialkoxysilanes, methyltrimethoxysilane and methyltriethoxysilane are preferable, and as the dialkoxysilanes, dimethyldimethoxysilane, Dimethyldiethoxysilane is preferred.

  In the present invention, the organosilane (1) is particularly preferably a trialkoxysilane alone or a combination of trialkoxysilane 40 to 95 mol% and dialkoxysilane 60 to 5 mol%. By using dialkoxysilane in combination with trialkoxysilane, the resulting coating film can be softened and alkali resistance can be improved.

Organosilane (1) is used as it is or as a hydrolyzate and / or condensate. When organosilane (1) is used as a hydrolyzate and / or condensate, it can be hydrolyzed and condensed in advance and used as component (a). However, as described later, organosilane (1) When preparing the composition by mixing with the remaining components, the organosilane (1) is hydrolyzed and condensed by adding an appropriate amount of water [component (d), etc., described later], and the component (a) It is preferable to do.
When the component (a) is used as a condensate, the polystyrene-equivalent weight average molecular weight (hereinafter referred to as “Mw”) of the condensate is preferably 800 to 100,000, more preferably 1,000 to 50, 000.

Commercially available products of the hydrolysis / condensation product of component (a) include MKC silicate manufactured by Mitsubishi Chemical Corporation, ethyl silicate manufactured by Colcoat, silicone resin manufactured by Toray Dow Corning, Toshiba Silicone Co., Ltd. made in silicone resin, manufactured by Shin-Etsu Chemical Co., Ltd. silicone resin, manufactured by Dow Corning Asia Ltd. of hydroxyl group-containing dimethyl polysiloxane include Nippon Unicar Co., Ltd. silicone oligomer, used by condensing May be.

  In this invention, (a) component can be used individually or in mixture of 2 or more types.

(B) a silyl group-containing polymer;
Component (b) is a heavy chain having a hydrolyzable group and / or a silyl group having a silicon atom bonded to a hydroxyl group (hereinafter referred to as “specific silyl group”), preferably at the terminal and / or side chain of the polymer molecular chain. Composed of coalescence.
In the coating composition of the present invention, the component (b) is excellent when the hydrolyzable group and / or hydroxyl group in the silyl group co-condenses with the component (a) when the coating film is cured. It is a component that provides coating film performance.
The content of the specific silyl group in the component (b) is usually 0.001 to 20% by weight, preferably 0.01, based on the polymer before the introduction of the specific silyl group in terms of the amount of silicon atoms. ~ 15% by weight.
A preferred specific silyl group is a group represented by the following general formula (2).

(R ⁵ ) _3-i
│ ………… (2)
-Si-X _i
(Wherein X represents a hydrolyzable group such as a halogen atom, an alkoxyl group, an acetoxy group, a phenoxy group, a thioalkoxyl group, an amino group, or a hydroxyl group, and R ⁵ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or An aralkyl group having 1 to 10 carbon atoms; i is an integer of 1 to 3)

The component (b) can be produced by, for example, the following methods (a) and (b).
(A) A hydrosilane compound corresponding to the general formula (2) (hereinafter referred to as “hydrosilane compound (a)”) is a vinyl polymer having a carbon-carbon double bond (hereinafter referred to as “unsaturated vinyl polymer”). ) In which the carbon-carbon double bond is subjected to an addition reaction.

(B) The following general formula (3)
(R ⁵ ) _3-i
│ ………… (3)
R ⁶ -Si-X _i
Wherein, X, R ^5, i has the same meaning as X, R ^5, i, respectively, in formula (2), R ⁶ represents an organic group having a polymerizable double bond] silane compound represented by (Hereinafter referred to as “unsaturated silane compound (b)”) and another vinyl monomer.

  Examples of the hydrosilane compound (a) used in the above method (a) include halogenated silanes such as methyldichlorosilane, trichlorosilane, and phenyldichlorosilane; methyldimethoxysilane, methyldiethoxysilane, and phenyldimethoxy. Alkoxysilanes such as silane, trimethoxysilane, and triethoxysilane; Acyloxysilanes such as methyldiacetoxysilane, phenyldiacetoxysilane, and triacetoxysilane; Methyldiaminoxysilane, triaminoxysilane, dimethylaminoxysilane And aminoxysilanes. These hydrosilane compounds (a) can be used alone or in admixture of two or more.

Further, the unsaturated vinyl polymer used in the method (a) is not particularly limited as long as it is other than a polymer having a hydroxyl group. For example, the following methods (a-1) and (a-2) Or it can manufacture by these combinations.
(A-1) After (co) polymerizing a vinyl monomer having a functional group (hereinafter referred to as “functional group (α)”), the functional group (α) in the (co) polymer By reacting an unsaturated compound having a functional group capable of reacting with the group (α) (hereinafter referred to as “functional group (β)”) and a carbon / carbon double bond, carbon- A method for producing an unsaturated vinyl polymer having a carbon double bond.

  (A-2) A radical polymerization initiator having a functional group (α) (for example, 4,4-azobis-4-cyanovaleric acid) is used, or both radical polymerization initiator and chain transfer agent are functional. Using a compound having a group (α) (for example, 4,4-azobis-4-cyanovaleric acid and dithioglycolic acid), the vinyl monomer is (co) polymerized to form a polymer molecular chain. After synthesizing a (co) polymer having a functional group (α) derived from a radical polymerization initiator or chain transfer agent at one or both ends, the functional group (α) in the (co) polymer is functionalized. An unsaturated vinyl polymer having a carbon-carbon double bond at one or both ends of a polymer molecular chain is produced by reacting an unsaturated compound having a group (β) with a carbon / carbon double bond. how to.

  Examples of the reaction between the functional group (α) and the functional group (β) in the methods (a-1) and (ii-2) include esterification reaction between a carboxyl group and a hydroxyl group, a carboxylic anhydride group and a hydroxyl group. Ring-opening esterification reaction, carboxyl group and epoxy group ring-opening esterification reaction, carboxyl group and amino group amidation reaction, carboxylic acid anhydride group and amino group ring-opening amidation reaction, epoxy group Ring-opening addition reaction between a hydroxyl group and an amino group, urethanization reaction between a hydroxyl group and an isocyanate group, a combination of these reactions, and the like.

Examples of vinyl monomers having a functional group (α) include unsaturated carboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid; maleic anhydride, itaconic anhydride and the like. Unsaturated carboxylic acid anhydrides; hydroxyl groups such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, N-methylol (meth) acrylamide, 2-hydroxyethyl vinyl ether -Containing vinyl monomers; amino group-containing vinyl monomers such as 2-aminoethyl (meth) acrylate, 2-aminopropyl (meth) acrylate, 3-aminopropyl (meth) acrylate, 2-aminoethyl vinyl ether; 1,1,1-trimethylamine (meth) acrylimide 1-methyl-1-ethylamine (meth) acrylimide, 1,1-dimethyl-1- (2-hydroxypropyl) amine (meth) acrylimide, 1,1-dimethyl-1- (2′-phenyl-2 ′) -Aminoimide group-containing vinyl monomers such as -hydroxyethyl) amine (meth) acrylimide, 1,1-dimethyl-1- (2'-hydroxy-2'-phenoxypropyl) amine (meth) acrylimide; glycidyl ( Examples thereof include epoxy group-containing vinyl monomers such as (meth) acrylate and allyl glycidyl ether.
These vinyl monomers having a functional group (α) can be used alone or in admixture of two or more.

Examples of other vinyl monomers copolymerizable with a vinyl monomer having a functional group (α) include:
(A) Styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methoxystyrene, 2-hydroxymethylstyrene, 4-ethylstyrene, 4-ethoxystyrene, 3,4- Dimethylstyrene, 3,4-diethylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-chloro-3-methylstyrene, 4-t-butylstyrene, 2,4-dichlorostyrene, 2,6-dichlorostyrene, Aromatic vinyl monomers such as 1-vinylnaphthalene;

  (B) Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, amyl (meth) acrylate, i-amyl (meth) acrylate , (Meth) acrylate compounds such as hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, cyclohexyl methacrylate;

  (C) Divinylbenzene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol Di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, butanediol di (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, penta Multifunctional monomers such as erythritol tetra (meth) acrylate;

(D) (Meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N'-methylenebisacrylamide, diacetone acrylamide, maleic acid amide Acid amide compounds such as maleimide;
(E) Vinyl compounds such as vinyl chloride, vinylidene chloride and fatty acid vinyl esters;
(F) 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-neopentyl-1,3-butadiene, 2-chloro-1,3-butadiene , Substituted linear conjugated pentadienes substituted with substituents such as 2-cyano-1,3-butadiene, isoprene, alkyl groups, halogen atoms, cyano groups, and aliphatic such as linear and side chain conjugated hexadienes Conjugated dienes;

(G) Vinyl cyanide compounds such as acrylonitrile and methacrylonitrile;
(H) Fluorine atom-containing monomers such as trifluoroethyl (meth) acrylate and pentadecafluorooctyl (meth) acrylate;
(Li) 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy -Piperidine monomers such as 1,2,2,6,6-pentamethylpiperidine;
Other examples include dicaprolactone.
These can be used alone or in combination of two or more.

  As an unsaturated compound having a functional group (β) and a carbon / carbon double bond, for example, a vinyl monomer similar to a vinyl monomer having a functional group (α), or the above hydroxyl group-containing vinyl system An isocyanate group-containing unsaturated compound obtained by reacting a monomer and a diisocyanate compound in an equimolar amount can be exemplified.

Moreover, as a specific example of the unsaturated silane compound (b) used in the method (b),
_{CH 2 = CHSi (CH 3)} (OCH 3) 2, CH 2 = CHSi (OCH 3) 3,
CH ₂ = CHSi (CH ₃ ) Cl ₂ , CH ₂ = CHSiCl ₃ ,
_{CH 2 = CHCOO (CH 2)} 2 Si (CH 3) (OCH 3) 2,
CH ₂ = CHCOO (CH ₂ ) ₂ Si (OCH ₃ ) ₃ ,
_{CH 2 = CHCOO (CH 2)} 3 Si (CH 3) (OCH 3) 2,
_{CH 2 = CHCOO (CH 2)} 3 Si (OCH 3) 3,
CH ₂ = CHCOO (CH ₂ ) ₂ Si (CH ₃ ) Cl ₂ ,
CH ₂ = CHCOO (CH ₂ ) ₂ SiCl ₃ , CH ₂ = CHCOO (CH ₂ ) ₃ Si (CH ₃ ) Cl ₂ ,
CH ₂ = CHCOO (CH ₂ ) ₃ SiCl ₃ ,
_{CH 2 = C (CH 3)} COO (CH 2) 2 Si (CH 3) (OCH 3) 2,
_{CH 2 = C (CH 3)} COO (CH 2) 2 Si (OCH 3) 3,
_{CH 2 = C (CH 3)} COO (CH 2) 3 Si (CH 3) (OCH 3) 2,
_{CH 2 = C (CH 3)} COO (CH 2) 3 Si (OCH 3) 3,
_{CH 2 = C (CH 3)} COO (CH 2) 2 Si (CH 3) Cl 2,
CH ₂ ═C (CH ₃ ) COO (CH ₂ ) ₂ SiCl ₃ ,
_{CH 2 = C (CH 3)} COO (CH 2) 3 Si (CH 3) Cl 2,
CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₃ SiCl ₃ ,

And so on.
These can be used alone or in combination of two or more.
Examples of the other vinyl monomer copolymerized with the unsaturated silane compound (b) include, for example, vinyl monomers having the functional group (α) exemplified for the method (b-1) and others. One or more types of vinyl monomers may be mentioned.

Examples of the polymerization method for producing the component (b) include a method in which a monomer is added all at once and polymerized, and after the polymerization of a part of the monomer, the remainder is continuously or intermittently. Or a method of continuously adding the monomer from the beginning of the polymerization.
Moreover, the polymerization method which combined these polymerization methods is also employable.
A preferred polymerization method includes solution polymerization. As the solvent used for the solution polymerization, usual solvents can be used, and among them, ketones and alcohols are preferable. In this polymerization, known polymerization initiators, molecular weight regulators, chelating agents, and inorganic electrolytes can be used.

Other examples of the component (b) include specific silyl group-containing epoxy resins, specific silyl group-containing polyester resins, and specific silyl group-containing fluororesins.
Examples of the specific silyl group-containing epoxy resin include epoxy groups in epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, aliphatic polyglycidyl ether, and aliphatic polyglycidyl ester. And aminosilanes having a specific silyl group, vinylsilanes, carboxysilanes, glycidylsilanes, and the like.
The specific silyl group-containing polyester resin is produced, for example, by reacting a carboxyl group or a hydroxyl group contained in the polyester resin with aminosilanes, carboxysilanes, glycidylsilanes or the like having a specific silyl group. Can do.
Furthermore, the specific silyl group-containing fluororesin includes, for example, aminosilanes, carboxysilanes, glycidylsilanes, etc., having a specific silyl group in the carboxyl group or hydroxyl group contained in a (co) polymer such as fluorinated ethylene. Can be made to react.

  (B) The polystyrene conversion weight average molecular weight (hereinafter referred to as “Mw”) of the component is preferably 2,000 to 100,000, more preferably 3,000 to 50,000.

  In this invention, (b) component can be used individually or in mixture of 2 or more types obtained as mentioned above.

In the present invention, the components (a) to (b) are used as an organic-inorganic hybrid polymer obtained by subjecting the component (a) to hydrolysis / condensation treatment in the presence of the component (b) . Furthermore, an organic-inorganic hybrid polymer in which the weight ratio of component (a) (in terms of complete condensate) / component (b) is 5/95 to 60/40 is preferable.
The organic-inorganic hybrid polymer used in the coating composition of the present invention is obtained by co-condensing the components (a) to (b). For example, the components (a) to (b) are co-condensed with the components (a) to (b) by adding (d) a hydrolysis / condensation catalyst and (e) water.

(D) hydrolysis / condensation catalyst;
The component (d) is a catalyst that accelerates the hydrolysis / condensation reaction of the component (a) and the component (b).
By using the component (d), the curing rate of the resulting coating film is increased, and the molecular weight of the polysiloxane resin produced by the polycondensation reaction of the organosilane component used is increased, resulting in strength, long-term durability, etc. An excellent coating film can be obtained, and the coating film can be thickened and painted easily.

As such component (d), acidic compounds, alkaline compounds, salt compounds, amine compounds, organometallic compounds and / or partial hydrolysates thereof (hereinafter referred to as organometallic compounds and / or partial hydrolysates thereof are combined. (Referred to as “organometallic compound etc.”).
Examples of the acidic compound include acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, alkyl titanic acid, p-toluenesulfonic acid, phthalic acid, and the like, preferably acetic acid.
Examples of the alkaline compound include sodium hydroxide and potassium hydroxide, and sodium hydroxide is preferable. Examples of the salt compounds include alkali metal salts such as naphthenic acid, octylic acid, nitrous acid, sulfurous acid, aluminate, and carbonic acid.

  Examples of the amine compound include ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, piperidine, piperazine, m-phenylenediamine, p-phenylenediamine, ethanolamine, triethylamine, and 3-aminopropyl. Trimethoxysilane, 3-aminopropyl triethoxysilane, 3- (2-aminoethyl) -aminopropyl trimethoxysilane, 3- (2-aminoethyl) -aminopropyl triethoxysilane, 3- (2 -Aminoethyl) -aminopropyl-methyl-dimethoxysilane, 3-anilinopropyl-trimethoxysilane, alkylamine salts, quaternary ammonium salts, as well as various curing agents for epoxy resins Aminopropyl trimethoxysilane - like it can be mentioned sex amines, preferably, 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 3- (2-aminoethyl).

  Examples of the organometallic compound include a compound represented by the following general formula (4) (hereinafter referred to as “organometallic compound (4)”), an alkyl having 1 to 10 carbon atoms bonded to the same tin atom. Examples thereof include tetravalent tin organometallic compounds having 1 to 2 groups (hereinafter referred to as “organotin compounds”), partial hydrolysates of these compounds, and the like.

M (OR ⁷ ) _r (R ⁸ COCHCOR ⁹ ) _s (4)
[In the formula, M represents zirconium, titanium, or aluminum, and R ⁷ and R ⁸ are the same or different and each represents an ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, t -A monovalent hydrocarbon group having 1 to 6 carbon atoms such as a butyl group, an n-pentyl group, an n-hexyl group, a cyclohexyl group, and a phenyl group, and R ⁹ is the same carbon number as R ⁷ and R ^8. 1-6 monovalent hydrocarbon groups, methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, sec-butoxy group, t-butoxy group, lauryloxy group, stearyloxy Represents an alkoxyl group having 1 to 16 carbon atoms such as a group, and r and s are integers of 0 to 4, and (r + s) = (valence of M). ]

Specific examples of the organometallic compound (4) include
(I) Tetra-n-butoxyzirconium, tri-n-butoxyethylacetoacetatezirconium, di-n-butoxybis (ethylacetoacetate) zirconium, n-butoxytris (ethylacetoacetate) zirconium, tetrakis (n Organic zirconium compounds such as propylacetoacetate) zirconium, tetrakis (acetylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium;

(B) Tetra-i-propoxy titanium, di-i-propoxy bis (ethylacetoacetate) titanium, di-i-propoxy bis (acetylacetate) titanium, di-i-propoxy bis (acetylacetone) titanium, etc. Organic titanium compounds;
(C) Tri-i-propoxyaluminum, di-i-propoxyethyl acetoacetate aluminum, di-i-propoxy acetylacetonate aluminum, i-propoxy bis (ethylacetoacetate) aluminum, i-propoxy bis ( Organoaluminum compounds such as acetylacetonato) aluminum, tris (ethylacetoacetate) aluminum, tris (acetylacetonato) aluminum, monoacetylacetonate bis (ethylacetoacetate) aluminum;
And so on.

  Among these organometallic compounds (4) and partial hydrolysates thereof, tri-n-butoxy ethylacetoacetate zirconium, di-i-propoxy bis (acetylacetonato) titanium, di-i-propoxy ethylacetate Acetate aluminum, tris (ethyl acetoacetate) aluminum, or a partial hydrolyzate of these compounds is preferred.

Specific examples of the organic tin compound include (C ₄ H ₉ ) ₂ Sn (OCOC ₁₁ H ₂₃ ) ₂ , (C ₄ H ₉ ) ₂ Sn (OCOCH═CHCOOCH ₃ ) ₂ , (C ₄ H ₉ ) _2. Sn (OCOCH = CHCOOC ₄ H ₉ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOC ₈ H ₁₇ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOC ₁₁ H ₂₃ ) ₂ , (C ₈ H ₁₇ ) _{2 Sn (OCOCH = CHCOOCH 3) 2} , (C 8 H 17) 2 Sn (OCOCH = CHCOOC 4 H 9) 2, (C 8 H 17) 2 Sn (OCOCH = CHCOOC 8 H 17) 2, (C 8 H 17 ) ₂ Sn (OCOCH = CHCOOC ₁₆ H ₃₃ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH = CHCOOC ₁₇ H ₃₅ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH = CHCOOC ₁₈ H ₃₇ ) ₂ , ( C ₈ H ₁₇ ) ₂ Sn (OCOCH═CHCOOC ₂₀ H _{41 2}

(C ₄ H ₉ ) ₂ SnOCOCH ₃
│
O
│
(C ₄ H ₉ ) ₂ SnOCOCH ₃ ,
(C ₄ H ₉ ) ₂ Sn (OCOC ₁₁ H ₂₃ ) ₃ ,
(C ₄ H ₉ ) ₂ Sn (OCONa) ₃
Carboxylic acid type organotin compounds such as;

_{(C 4 H 9) 2 Sn} (SCH 2 COOC 8 H 17) 2,
_{(C 4 H 9) 2 Sn} (SCH 2 CH 2 COOC 8 H 17) 2,
_{(C 8 H 17) 2 Sn} (SCH 2 COOC 8 H 17) 2,
_{(C 8 H 17) 2 Sn} (SCH 2 CH 2 COOC 8 H 17) 2,
_{(C 8 H 17) 2 Sn} (SCH 2 COOC 12 H 25) 2,
_{(C 8 H 17) 2 Sn} (SCH 2 CH 2 COOC 12 H 25) 2,
_{(C 4 H 9) Sn (} SCOCH = CHCOOC 8 H 17) 3,
_{(C 8 H 17) Sn (} SCOCH = CHCOOC 8 H 17) 3,

(C ₄ H ₉ ) ₂ Sn (SCH ₂ COOC ₈ H ₁₇ )
│
O
│
(C ₄ H ₉ ) ₂ Sn (SCH ₂ COOC ₈ H ₁₇ )
Mercaptide-type organotin compounds such as

(C ₄ H ₉ ) ₂ Sn = S, (C ₈ H ₁₇ ) ₂ Sn = S,
(C ₄ H ₉ ) ₂ Sn = S
│
O
│
(C ₄ H ₉ ) ₂ Sn = S
Sulfide-type organotin compounds such as;

(C ₄ H ₉ ) SnCl ₃ , (C ₄ H ₉ ) ₂ SnCl ₂ , (C ₈ H ₁₇ ) ₂ SnCl ₂ ,
_{(C 4 H 9) 2 Sn} -Cl
│
O
│
_{(C 4 H 9) 2 Sn} -Cl
Chloride-type organotin compounds such as: organotin oxides such as (C ₄ H ₉ ) ₂ SnO, (C ₈ H ₁₇ ) ₂ SnO, and these organotin oxides and silicates, dimethyl maleate, diethyl maleate, phthalic acid Reaction products with ester compounds such as dioctyl;
And so on.

  (D) A component can be used individually or in mixture of 2 or more types, and can also be used in mixture with a zinc compound and another reaction retarder.

The component (d) is blended when preparing an organic-inorganic hybrid polymer that is a cocondensate of the components (a) to (b) of the present invention. You may mix | blend in both of these steps.
The amount of component (d) used is usually 0 to 100 parts by weight, preferably 0.01 to 100 parts by weight of organosilane (1) in component (a), except for organometallic compounds. 80 parts by weight, more preferably 0.1 to 50 parts by weight. In the case of an organometallic compound, etc., usually 0 to 100 parts by weight with respect to 100 parts by weight of the organosilane (1) in the component (a). The amount is preferably 0.1 to 80 parts by weight, and more preferably 0.5 to 50 parts by weight. In this case, when the amount of the component (f) used exceeds 100 parts by weight, the storage stability of the composition tends to be reduced, and cracks tend to occur in the coating film.

(E) water;
The coating composition of the present invention essentially comprises the above components (a) to (b) and (c) a siloxane oligomer, and optionally contains components (f) to (h) which will be described later. In preparing the composition, (e) water causes hydrolysis / condensation reaction of the organosilane (1), or an organic-inorganic hybrid polymer is obtained from the components (a) to (b). It is added to disperse the particulate component.
The amount of (e) water used in the present invention is usually 0.5 to 3 mol, preferably about 0.7 to 2 mol, per 1 mol of organosilane (1) in component (a).
In addition, the said (e) water includes the water which may be contained in an organic solvent or a postscript (f)-(h) component.

In addition, the composition of this invention can also use an organic solvent together with (e) water.
The organic solvent is mainly composed of the components (a) to (b) and the organic-inorganic hybrid polymer composed of the components (a) to (b), the component (c), and the components (f) to (h) described later. It is used to mix and adjust the total solids concentration of the composition, while making it applicable to various coating methods, and to further improve the dispersion stability and storage stability of the composition.

  Such an organic solvent is not particularly limited as long as the above components can be mixed uniformly, and examples thereof include alcohols, aromatic hydrocarbons, ethers, ketones, esters and the like. . Among these organic solvents, specific examples of alcohols include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, sec-butyl alcohol, t-butyl alcohol, n-hexyl alcohol, n -Octyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene monomethyl ether acetate, diacetone alcohol and the like.

Specific examples of aromatic hydrocarbons include benzene, toluene and xylene, specific examples of ethers include tetrahydrofuran and dioxane, and specific examples of ketones include acetone, methyl ethyl ketone, and methyl isobutyl ketone. Specific examples of esters such as diisobutylketone and the like include ethyl acetate, propyl acetate, butyl acetate, and propylene carbonate. These organic solvents can be used alone or in admixture of two or more.
In addition, the said organic solvent includes the organic solvent which may be contained in said (a)-(b) component and a postscript (f)-(h) component.

In the coating composition of the present invention, an appropriate amount of water [component (d)] is added to the organosilane (1), and the organosilane (1) is hydrolyzed / condensed in the presence of the component (b) to form an organic An inorganic hybrid polymer is preferred.
Moreover, as above-mentioned, the hydrolyzate and / or condensate of organosilane (1) can also be used as (a) component.

In the present invention, an organic-inorganic hybrid polymer is prepared by adding (d) a hydrolysis / condensation catalyst and (e) water to components (a) to (b), and combining components (a) to (b). For example, the following preparation methods (1) to (3) are preferable.
(1) In a solution comprising the organosilane (1) constituting the component (a), (b) a silyl group-containing polymer, and (d) a hydrolysis / condensation catalyst, 0.1 to 0.1 mol of the organosilane A composition containing an organic-inorganic hybrid polymer comprising the components (a) to (b) by adding 3 moles of (e) water and co-condensing the mixture at a temperature of 40 to 80 ° C. for a reaction time of 0.5 to 12 hours. Then, if necessary, other additives such as component (h) to be described later are added.
(2) 0.1-3 mol of (e) water is added to 1 mol of the organosilane (1) constituting the component (a), the temperature is 40-80 ° C., the reaction time is 0.5-12 hours, and the hydrolysis is performed.・ Condensation reaction is performed, and then (b) a silyl group-containing polymer and (d) a hydrolysis / condensation catalyst are added and mixed. Further, the temperature temperature is 40 to 80 ° C., the reaction time is 0.5 to 12 hours, and the condensation reaction is performed. After preparing the composition containing the organic-inorganic hybrid polymer comprising the components (a) to (b), other additives such as the component (h) described below are further added as necessary.
(3) The organosilane (1) and (b) silyl group-containing polymer constituting the component (a) are added to a solution obtained by adding (d) a hydrolysis / condensation catalyst and a component (h) described later to the organosilane. 0.01 to 3 mol of (e) water is added to 1 mol of silane, and a hydrolysis / condensation reaction is performed at a temperature of 40 to 80 ° C. for a reaction time of 0.5 to 12 hours. After preparing the composition containing the organic-inorganic hybrid polymer which consists of b) component, other additives, such as a postscript (h) component, are further added.

The blending ratio of the components (a) to (b) in the organic-inorganic hybrid polymer used in the coating composition of the present invention is such that the weight ratio of the component (a) (completely hydrolyzed product) / (b) component is 5/95. It is -70/30, Preferably it is 5 / 95-60 / 40, More preferably, it is 10 / 90-50 / 50.
Here, the completely hydrolyzed condensate of the component (a) refers to a product in which the R ² O— group of the organosilane is hydrolyzed to become a SiOH group and further condensed to a siloxane.
When the blending ratio of the component (b) in the organic-inorganic hybrid polymer is less than 30% by weight, the adhesion to the substrate may be inferior, or the resulting coating film itself may be inferior in alkali resistance. On the other hand, if it exceeds 95% by weight, the proportion of the organic component constituting the component (b) in the composition increases, and for example, the organic component deteriorates due to radicals generated from the photocatalyst contained in the overcoat layer, and contains a photocatalyst. Long-term adhesion with the coating film decreases.

(C) a siloxane oligomer;
(C) component, the average compositional formula _{^{R 3 p Si (OR 4)}} q O (4-pq) / 2 ( wherein, R ³ is one or two monovalent organic group having 1 to 18 carbon atoms R ⁴ is a hydrogen group or one or more monovalent organic groups having 1 to 4 carbon atoms, and p and q are 0 ≦ p ≦ 1.8, 0 <Q <3.3 and 0 <p + q <4).
(C) Component is a condensation reaction at the time of hardening of the undercoat layer which consists of a composition obtained by post-adding to the organic-inorganic hybrid polymer which consists of (a)-(b) component or (a)-(b) component The adhesiveness to an organic base material can be secured. In addition, when coating a photocatalyst-containing composition that is an overcoating layer in excess of water, the OR ⁴ group is hydrolyzed and condensed by moisture in the overcoating composition or moisture in the air, and adhesion to this overcoating layer Can be secured.
In addition, in the average composition formula of the component (c), 0 ≦ p ≦ 1 and a siloxane oligomer obtained from a tetrafunctional / trifunctional / bifunctional silane derivative is preferable because adhesion is improved.
In addition, in the average composition formula of component (c), the siloxane oligomer composed of one or more siloxane oligomers where P = 0 and / or 1 is a tetrafunctional oligomer and / or a trifunctional oligomer, This is preferable from the viewpoint of containing a large number of OR ⁴ groups for improving the properties.
Further, R ⁴ is particularly preferably one or more of monovalent organic groups having 1 to 4 carbon atoms. R ⁴ is one or two or more monovalent organic groups having 1 to 4 carbon atoms, thereby suppressing condensation reactivity at the time of curing the undercoat coating composition of the present invention, and an organic base material layer. In addition, the siloxane oligomer can be hydrolyzed and condensed during coating of the overcoat layer (photocatalyst-containing layer) to ensure adhesion with the overcoat layer. Further, it is particularly preferable that water is contained in the topcoat layer because the hydrolysis and condensation of the component (c) further progresses during coating of the topcoat layer, and the adhesion with the topcoat layer becomes stronger.
In addition, as component (c), the use of at least one siloxane oligomer having one or two or more monovalent organic groups having 2 to ⁴ carbon atoms as R ⁴ suppresses hydrolysis during long-term storage. It is preferable because storage stability can be secured.

The component (c) is composed of, for example, an uncured siloxane oligomer formed by partially hydrolyzing / condensing a hydrolyzable silane derivative monomer. The uncured siloxane oligomer has a general formula R ₂ SiX ₂ (wherein R is a monovalent organic group having 1 to 18 carbon atoms, X is chlorine, bromine, or an alkoxy group having 1 to 4 carbon atoms). A hydrolyzable bifunctional silane derivative represented by the general formula RSiX ₃ , and a hydrolyzable tetrafunctional silane derivative represented by the general formula SiX ₄ Prepared from

Hydrolyzable silane derivative constituting the component (c) to ensure the OR ⁴ available to co-condensation with the photocatalyst layer has a three hydrolyzable groups X per trifunctional silane derivative (molecules, each silicon A monomer that forms a trifunctional siloxane bond in which three oxygen atoms are bonded to each other), and / or a tetrafunctional silane derivative (four hydrolyzable groups X (chlorine, bromine, or alkoxy groups) per molecule; It is preferable to form a tetrafunctional siloxane bond in which four oxygen atoms are bonded to each silicon atom.
In this way, this film-forming element composed of an uncured siloxane oligomer formed by partially hydrolyzing / condensing a hydrolyzable silane derivative monomer has an average composition formula R ³ _p Si (OR ⁴ ) _Q O _{(4-pq) / 2} (wherein R ³ is a functional group consisting of one or more monovalent organic groups having 1 to 18 carbon atoms, and R ⁴ is a hydrogen group, or , One or more monovalent organic groups having 1 to 4 carbon atoms, and p and q satisfy 0 ≦ p ≦ 1.8, 0 <q <3.3, and 0 <p + q <4 It is a number to do).
As the component (c), two or more different siloxane oligomers can be used.

Examples of hydrolyzable trifunctional silane derivatives include methyltrichlorosilane, methyltribromosilane, ethyltrichlorosilane, ethyltribromosilane, vinyltribromosilane, vinyltrichlorosilane, trichlorohydrosilane, tribromohydrosilane, methyltrimethoxysilane, Methyltriethoxysilane, methyltriisopropoxysilane, methyltrit-butoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, trimethoxyhydrosilane, triethoxyhydrosilane Can be mentioned.
Examples of hydrolyzable tetrafunctional silane derivatives include tetrachlorosilane, tetrabromosilane, tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, and dimethoxydiethoxysilane.
Examples of hydrolyzable bifunctional silane derivatives include dimethyldichlorosilane, dimethyldibromosilane, dimethyldimethoxysilane, and dimethyldiethoxysilane.

  Suitable hydrolyzable trifunctional silane derivative monomers having an organic group having 3 or more carbon atoms include n-propyltrichlorosilane, n-propyltribromosilane, n-hexyltrichlorosilane, n-hexyltribromosilane, and phenyltrichloro. Silane, phenyltribromosilane, trifluoropropyltrichlorosilane, trifluoropropyltribromosilane, trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, heptadecafluorooctyltrimethoxysilane, heptadecafluorooctyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltriisopropoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, n Decyltrimethoxysilane, n-decyltriethoxysilane, n-octadecyltrimethoxysilane, n-octadecyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycid Xylpropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, γ- (meth) acryloxypropyltrimethoxysilane, γ- There are (meth) acryloxypropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane.

  Suitable hydrolyzable bifunctional silane derivative monomers having an organic group having 3 or more carbon atoms include diphenyldichlorosilane, diphenyldibromosilane, phenylmethyldibromosilane, diphenyldimethoxysilane, diphenyldiethoxysilane, and phenylmethyldiphenyl. Chlorosilane, heptadecafluorooctylmethyldimethoxysilane, heptadecafluorooctylmethyldiethoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxy Silane, γ- (meth) acryloxypropylmethyldimethoxysilane, γ- (meth) acryloxypropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-amino It is propyl methyl diethoxy silane.

  (C) As a component, it is the weight average molecular weight of polystyrene conversion, and is 200-100,000 normally, Preferably it is 300-50,000.

Moreover, the commercially available products of the component (c), manufactured by Mitsubishi Chemical Corporation MKC silicate Colcoat Co. ethyl silicate, manufactured by Dow Corning Toray Co. silico - down resin, Toshiba Silicone Co., Ltd. Silicone resin, Shin-Etsu Chemical Co. There are silicone resins manufactured by Dow Corning Asia Co., Ltd., hydroxyl group-containing polydimethylsiloxane manufactured by Dow Corning Asia, silicone oligomers manufactured by Nihon Unicar Company, etc., and these may be used as they are.

  The use ratio of the above (a), (b) and (c) siloxane oligomer is 1 to 100 in terms of solid content, with respect to 100 parts by weight of the total of (a) component and (b) component. % By weight, preferably 2 to 70% by weight. If the amount of component (c) used is less than 1 part by weight, the adhesion of the topcoat layer to the photocatalyst-containing coating film will be inferior. On the other hand, if it exceeds 100 parts by weight, whitening may occur during film formation, or overcoating The undercoat layer obtained from the composition of the present invention may be dissolved during coating of the photocatalyst-containing coating material of the layer.

  The following components (f) to (h) can be further blended in the coating composition of the present invention. Hereinafter, these components will be described.

(F) inorganic fillers;
(F) Examples of the inorganic filler include powders and / or sols or colloids of inorganic compounds, which are blended according to the desired properties of the coating film. When the component (f) is sol or colloid, the average particle size is usually about 0.005 to 100 μm.

Specific examples of the compound constituting the component _{(f), SiO 2, Al 2 O 3} , AlGaAs, Al (OH) 3, Sb 2 O 5, Si 3 N 4, Sn-In 2 O 3, Sb-In 2 O ₃ , MgF, CeF ₃ , CeO ₂ , 3Al ₂ O ₃ .2SiO ₂ , BeO, SiC, AlN, Fe, Co, Co—FeO _x , CrO ₂ , Fe ₄ N, BaTiO ₃ , BaO—Al ₂ O ₃ -SiO _2, Ba _{ferrite, SmCO 5, YCO 5, CeCO} 5, PrCO 5, Sm 2 CO 17, Nd 2 Fe 14 B, Al 4 O 3, α-Si, SiN 4, CoO, Sb-SnO 2, Sb ₂ O ₅ , MnO ₂ , MnB, Co ₃ O ₄ , Co ₃ B, LiTaO ₃ , MgO, MgAl ₂ O ₄ , BeAl ₂ O ₄ , ZrSiO ₄ , ZnSb, PbTe, GeSi, FeSi ₂ , CrSi ₂ , CoSi ₂ , MnSi _{1.7 3} , Mg ₂ Si, β-B, BaC, BP, TiB ₂ , ZrB ₂ , HfB ₂ , Ru ₂ Si ₃ , TiO ₂ (rutile type), TiO ₃ , PbTiO ₃ , Al ₂ TiO ₅ , Zn ₂ SiO _{4 , Zr 2 SiO 4, 2MgO 2} -Al 2 O 3 -5SiO 2, Nb 2 O 5, Li 2 O-Al 2 O 3 -4SiO 2, Mg ferrite, Ni ferrite, Ni-Zn ferrite, Li ferrite, Sr ferrite And so on.
These components (f) can be used alone or in admixture of two or more.

  Component (f) is present in the form of a powder, an aqueous sol or colloid dispersed in water, a polar solvent such as isopropyl alcohol, or a solvent sol or colloid dispersed in a nonpolar solvent such as toluene. In the case of a solvent-based sol or colloid, depending on the dispersibility of the semiconductor, it may be further diluted with water or a solvent, or may be used after a surface treatment to improve the dispersibility.

When the component (f) is an aqueous sol or colloid, or a solvent sol or colloid, the solid content concentration is preferably 40% by weight or less.
The component (f) of the present invention is particularly preferably colloidal silica. Examples of the colloidal silica include aqueous colloidal silica in which the dispersion solvent is water, and examples of the dispersion solvent include alcohols such as i-propyl alcohol, n-propyl alcohol, and methanol, and ketone-based organic solvent colloidal silica such as methyl ethyl ketone. .

  As a method of blending the component (f) in the composition, it may be added after the preparation of the composition, or added during the preparation of the composition, and the component (f) is added to the component (a), ( You may make it co-hydrolyze and condense with b) component or the said condensate.

  (F) The usage-amount of a component is 10-900 weight part with respect to 100 weight part of solid content of (a) + (b) + (c) in conversion of solid content, Preferably it is 20-300 weight part. If it is less than 10 parts by weight, it may be deteriorated by radicals in the photocatalyst layer. On the other hand, if it exceeds 900 parts by weight, it may become brittle as a coating film and may have poor film forming properties.

(G) UV absorber and / or UV stabilizer The photocatalyst-containing coating undercoating composition of the present invention is for the purpose of protecting the UV degradation of the organic substrate and improving long-term weather resistance and durability adhesion. UV absorbers, UV stabilizers, and the like may be blended.
Examples of ultraviolet absorbers include inorganic semiconductors such as ZnO, TiO ₂ (not showing a photocatalytic function), and CeO ₂ ; organic ultraviolet absorbers such as salicylic acid, benzophenone, benzotriazole, cyanoacrylate, and triazine Is mentioned. Moreover, piperidine type | system | group etc. are mentioned as a ultraviolet stabilizer.
In particular, when colloidal silica is used as the component (e), it is preferable to use an inorganic semiconductor ultraviolet absorber in view of preventing bleeding from the coating film and preventing deterioration.
The usage-amount of a ultraviolet absorber and / or a ultraviolet stabilizer is 5-90 weight% in conversion of solid content, Preferably it is 10-80 weight%.

(H) component;
The component (h) is represented by the following general formula (5)
R ⁶ COCH ₂ COR ⁷ (5)
Wherein, R ⁶ and R ^7, the organometallic compound is synonymous with each R ⁶ and R ⁷ in each of the general formulas in (4)] β- diketones represented by and β- ketoesters, carboxylic acid It is at least one selected from the group consisting of a compound, a dihydroxy compound, an amine compound, and an oxyaldehyde compound.
Such a component (h) is preferably used in combination when an organometallic compound or the like is used as the component (d).

  The component (h) acts as a stability improver for the composition. That is, the component (h) is coordinated to a metal atom such as the organometallic compound, and the action of promoting the cocondensation reaction between the component (a) and the component (b) by the organometallic compound is moderately controlled. Therefore, it is presumed that the resulting composition further improves the storage stability.

Specific examples of the component (h) include acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate-sec-butyl, acetoacetate -T-butyl, hexane-2,4-dione, heptane-2,4-dione, heptane-3,5-dione, octane-2,4-dione, nonane-2,4-dione, 5-methylhexane- 2,4-dione, malonic acid, oxalic acid, phthalic acid, glycolic acid, salicylic acid, aminoacetic acid, iminoacetic acid, ethylenediaminetetraacetic acid, glycol, catechol, ethylenediamine, 2,2-bipyridine, 1,10-phenanthroline, diethylenetriamine, 2-ethanolamine, dimethylglyoxime, dithizone, methionine, salicylua Or the like can be mentioned dehydrogenase. Of these, acetylacetone and ethyl acetoacetate are preferred.
(H) A component can be used individually or in mixture of 2 or more types.

  (H) The usage-amount of a component is 2 mol or more normally with respect to 1 mol of organometallic compounds in the said organometallic compound etc., Preferably it is 3-20 mol. In this case, if the amount of component (h) used is less than 2 mol, the effect of improving the storage stability of the resulting composition tends to be insufficient.

Other additives;
In addition, a filler can be separately added and dispersed in the composition of the present invention for coloring or thickening the resulting coating film. Examples of such fillers include water-insoluble organic pigments and inorganic pigments, particulate, fibrous or scale-like ceramics, metals or alloys other than pigments, and oxides and hydroxides of these metals. , Carbides, nitrides, sulfides and the like.

Specific examples of the other fillers include iron, copper, aluminum, nickel, silver, zinc, ferrite, carbon black, stainless steel, silicon dioxide, titanium oxide for pigment, aluminum oxide, chromium oxide, manganese oxide, iron oxide. , Zirconium oxide, cobalt oxide, synthetic mullite, aluminum hydroxide, iron hydroxide, silicon carbide, silicon nitride, boron nitride, clay, diatomaceous earth, slaked lime, gypsum, talc, barium carbonate, calcium carbonate, magnesium carbonate, barium sulfate, Bentonite, mica, zinc green, chrome green, cobalt green, viridian, guinea green, cobalt chrome green, chellet green, green earth, manganese green, pigment green, ultramarine, bitumen, rock ultramarine, cobalt blue, cerulean blue, copper borate , Molybdenum blue, copper sulfide, cobalt purple, mars purple, man Purple, Pigment Violet, Lead Oxide, Calcium Leadate, Zinc Yellow, Lead Sulfide, Chrome Yellow, Ocher, Cadmium Yellow, Strontium Yellow, Titanium Yellow, Resurge, Pigment Yellow, Cuprous Oxide, Cadmium Red, Selenium Red, Chromium Bar Million, Bengala, zinc white, antimony white, basic lead sulfate, titanium white, lithopone, lead silicate, zircon oxide, tungsten white, lead, zinc white, bunchison white, lead phthalate, manganese white, lead sulfate, graphite, Examples include bone black, diamond black, thermatomic black, vegetable black, potassium titanate whisker, and molybdenum disulfide.
These other fillers can be used alone or in admixture of two or more.
The amount of the other filler used is usually 300 parts by weight or less with respect to 100 parts by weight of the total solid content of the composition.

  Furthermore, the composition of the present invention may optionally contain a known dehydrating agent such as methyl orthoformate, methyl orthoacetate, tetraethoxysilane; polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, Dispersants such as polycarboxylic acid type polymer surfactant, polycarboxylate, polyphosphate, polyacrylate, polyamide ester salt, polyethylene glycol; methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, etc. Thickeners such as celluloses, castor oil derivatives, ferrosilicates; ammonium carbonate, ammonium bicarbonate, ammonium nitrite, sodium borohydride, calcium azide In addition to inorganic foaming agents, azo compounds such as azobisisobutyronitrile, hydrazine compounds such as diphenylsulfone-3,3'-disulfohydrazine, organic foaming agents such as semicarbazide compounds, triazole compounds, and N-nitroso compounds In addition, other additives such as a surfactant, a silane coupling agent, a titanium coupling agent, and a dye may be blended.

  Moreover, a leveling agent can be mix | blended in order to improve the coating property of the composition of this invention more. Among such leveling agents, examples of the fluorine-based leveling agent (trade name; hereinafter the same) include BM1000 and BM1100 of BM-CHEMIE; Fuka 772 and Fuka 777 of Fuka Chemicals; Kyoeisha Chemical Co., Ltd. Fluoren series manufactured by Sumitomo 3M Co., Ltd .; Fluoronal TF series manufactured by Toho Chemical Co., Ltd. and the like. Examples of silicone leveling agents include BYK series manufactured by BYK Chemie; (Sshmegmann) Sshmego series; EFKA Chemicals EFKA 30, EFKA 31, EFKA 34, EFKA 35, EFKA 36, EFKA 39, EFKA 83, EFKA 86, EFKA 88, etc., ether type or ester System The coupling agent, for example, Kafinoru of Nissin Chemical Industry Co., Kao Corp. Emulgen, and the like Homogenol.

  By blending such a leveling agent, the finished appearance of the coating film is improved, and it can be uniformly applied as a thin film. The amount of the leveling agent used is preferably 0.01 to 5% by weight, more preferably 0.02 to 3% by weight, based on the total composition.

  As a method of blending the leveling agent, it may be blended when preparing the composition, or may be blended into the composition at the stage of forming the coating film, and further, preparation of the composition and formation of the coating film. And may be blended in both stages.

  In addition, you may blend other resin with the coating composition of this invention. Examples of other resins include acrylic-urethane resins, epoxy resins, polyesters, acrylic resins, fluororesins, acrylic resin emulsions, epoxy resin emulsions, polyurethane emulsions, and polyester emulsions.

  In preparing the composition of the present invention, it is preferable to use a method in which (h) component is added to (a) to (h) after obtaining a mixture excluding (h) component. The

  The total solid concentration for the coating composition of the present invention is usually 50% by weight or less, preferably 40% by weight or less, and is appropriately adjusted according to the type of substrate, coating method, and coating film thickness. .

Photocatalyst-containing coating film The photocatalyst-containing coating film provided on the upper part of the coating film obtained from the coating composition of the present invention is usually obtained by applying a coating composition containing a photocatalyst and drying it. The coating composition is not particularly limited as long as it is a coating composition containing a photocatalyst. For example, conventional coating compositions such as organosilane compounds (and / or condensates thereof) and silyl group-containing polymers. And a composition containing a photocatalyst and a coating composition containing a conventionally proposed photocatalyst component. Specific examples thereof include various compositions listed in the “prior art” of the present invention (see paragraphs “0002” to “0009”).
In particular, the coating composition (II) or (III) having the following composition is preferred.

(II)
(A) The following general formula (1)
(R ¹ ) _n Si (OR ² ) _4-n (1)
(Wherein R ¹ is the same or different when two are present, and represents a monovalent organic group having 1 to 8 carbon atoms; R ² is the same or different and is an alkyl group or carbon having 1 to 5 carbon atoms; At least 1 selected from the group consisting of organosilanes, hydrolysates of the organosilanes, and condensates of the organosilanes represented by formulas 1 to 6 and n is an integer of 0 to 2. seed,
(B) a polymer containing a hydrolyzable group and / or a silyl group having a silicon atom bonded to a hydroxyl group, and (i) a coating composition containing a photocatalyst (hereinafter also referred to as “composition (II)”).
(III) A coating composition containing the component (a) and (i) a photocatalyst (hereinafter also referred to as “composition (III)”).

In the coating film obtained from the composition (II) and the composition (III), usually, (i) the photocatalyst has a bond with the component (a), etc., and the coating film has hydrophilicity and stain resistance. Sustained for a long time.
Here, the types and composition ratios of the component (a) and the component (b) in the composition (II) and the composition (III) are the same as those in the coating composition (I) of the present invention, and thus are omitted.
In addition, the components (f) to (h) may be blended in the composition (II) and the composition (III). The types and composition ratios of the components (f) to (h) are the same as those of the coating composition (I) of the present invention.

(I) a photocatalyst;
A preferable photocatalyst used for the photocatalyst coating film includes a semiconductor having photocatalytic activity. Examples of the semiconductor having photocatalytic activity include TiO ₂ , TiO ₃ , SrTiO ₃ , FeTiO ₃ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , In ₂ O ₃ , ZnO, Fe ₂ O ₃ , RuO ₂ , CdO, CdS, CdSe, GaP, GaAs, CdFeO ₃ , MoS ₂ , LaRhO ₃ , GaN, CdP, ZnS, ZnSe, ZnTe, Nb ₂ O ₅ , ZrO ₂ , InP, GaAsP, InGaAlP, AlGaAs, PbS, InAs, PbSe, InSb Of these, preferred are TiO ₂ and ZnO, and particularly preferred is anatase-type TiO ₂ .

The semiconductor is preferably used in the form of powder and / or sol. Specifically, it is desirable to take any one of three modes: powder, an aqueous sol dispersed in water, and a polar solvent such as isopropyl alcohol and an organic solvent sol dispersed in a nonpolar solvent such as toluene. In the case of a solvent-based sol, depending on the dispersibility of the semiconductor, it may be further diluted with water or a solvent. The average particle size of the semiconductor in these existing forms is preferably as small as possible from the viewpoint of photocatalytic activity, and is preferably 0.3 μm or less. Particularly preferably, it is 0.2 μm or less. In this case, when the average particle diameter of the semiconductor exceeds 0.3 μm, the coating film becomes opaque due to the light concealing action of the semiconductor. Moreover, a coating film will become transparent as it is 0.3 micrometer or less. Therefore, the average particle diameter of the semiconductor can be appropriately selected according to the use of the composition.
A particularly preferred component (i) is a titanium oxide sol dispersed in water. Moreover, even if it is an organic solvent type | system | group sol manufactured using the powdered titanium oxide and titanium alkoxide as a raw material, in photocatalyst containing coating composition (II) or (III), Preferably it is 1 weight with respect to titanium oxide solid content. % Or more, more preferably 2% by weight or more of water is desirable.
Thus, by containing water in the photocatalyst-containing coating composition coated on the undercoat coating composition of the present invention, the hydrolysis condensation of the component (c) in the undercoat composition proceeds, Adhesion is improved by forming a silanol bond between the undercoat layer and the overcoat layer.
In particular, when R ^{4 of} component (c) is a monovalent organic group having 1 to ⁴ carbon atoms, it is preferable to contain moisture in the photocatalyst-containing coating composition.

  In the composition (II) and the composition (III), when the component (i) is an aqueous sol or a solvent sol, the solid content concentration is preferably 50% by weight or less, more preferably 40% by weight or less. .

As a method of blending the component (i) in the composition (II) and the composition (III), the above components (a) to (b), or the component (a), and the components (f) to (h) May be added after the preparation of the composition comprising, or added during the preparation of the composition, and in the presence of the component (i), the components (a) to (b), or the component (a), etc. Can also be hydrolyzed and condensed.
When the component (i) is added during the preparation of the composition, the semiconductor compound in the component (i) can be co-condensed with the components (a) to (b) or the component (a), etc. Long-term durability is particularly improved. In addition, when the component (i) is an aqueous sol, it is preferably added at the time of preparing the composition. Further, when the viscosity in the system increases due to the blending of the component (h), (i) It is preferable to add the component at the time of preparing the composition.
Furthermore, when the composition used in the present invention is used as an enamel containing a coloring component, the color may be adjusted after adding the component (i) to the composition, and the component (i) You may add a coloring component to a composition simultaneously.

In this invention, (i) component can be used individually or in mixture of 2 or more types.
The usage-amount of (i) component in a photocatalyst containing coating film is 10-90 weight% normally in conversion of solid content, Preferably, it is 20-80 weight%. If it is less than 10% by weight, the antifouling effect due to the photocatalytic reaction may be insufficient. On the other hand, if it exceeds 90% by weight, the film formability may be deteriorated.

  Moreover, the total solid concentration of the composition (II) and the composition (III) is preferably 50% by weight or less, and is appropriately adjusted according to the purpose of use. For example, when it is intended to impregnate a thin film forming substrate, it is usually 0.1 to 10% by weight. When it is used for the purpose of forming a thick film, it is usually 10 to 50% by weight, preferably 10 to 10% by weight. 30% by weight. When the total solid concentration of the composition exceeds 50% by weight, the storage stability tends to decrease.

Structure The structure obtained by using the coating composition of the present invention includes a base material / a coating film comprising the coating composition of the present invention (coating composition for undercoat) / a photocatalyst-containing coating film, or a base material. / Primer / Coating film comprising the coating composition of the present invention (coating composition for undercoat) / Photocatalyst-containing coating film.
When applying the composition of the present invention to a substrate, a brush, a roll coater, a flow coater, a centrifugal coater, an ultrasonic coater, etc. are used, dip coating, flow coating, spraying, screen process, electrodeposition, vapor deposition, etc. As a dry film thickness, it is possible to form a coating film having a thickness of about 0.05 to 20 μm by one coating and a thickness of about 0.1 to 40 μm by two coatings. Thereafter, the coating film can be formed by drying at room temperature or by heating for about 1 to 60 minutes and drying at a temperature of about 30 to 200 ° C.
In addition, the photocatalyst-containing coating film can form a coating film having a dry thickness of about 0.05 to 20 μm by one coating and a thickness of about 0.1 to 40 μm by two coatings. Thereafter, the coating film can be formed on the undercoat layer by drying at room temperature or by heating and drying at a temperature of about 30 to 200 ° C. for about 1 to 60 minutes. The total film thickness of the undercoat layer and the topcoat layer is a dry film thickness and is usually about 0.1 to 80 μm, and preferably about 0.2 to 60 μm.

In the structure of the present invention, the coating film (undercoat layer) or the photocatalyst-containing coating film made of the coating composition of the present invention can be a so-called gradient material whose composition changes sequentially in the film thickness direction.
The gradient material is, for example, (1) a method in which the coating composition or the photocatalyst-containing coating film of the present invention is applied in multiple layers, and the composition of each layer is sequentially changed; After coating the substrate by spin coating or the like, place the coated substrate in parallel with the ground or reverse 180 degrees and leave it for a certain period of time, for example, inorganic filling as component (c) The agent can be formed by a method such as settling in the direction of gravity.

The substrate capable of applying the composition of the substrate present invention, for example, iron, aluminum, metal such as stainless steel; cement, concrete, ALC, flexible boards, mortar, slate, gypsum, ceramics, inorganic ceramic-based, such as bricks In addition to materials, organic base materials such as phenol resin, epoxy resin, polyester, polycarbonate, polyethylene, polypropylene, ABS resin (acrylonitrile-butadiene-styrene resin), etc .; polyethylene, polypropylene, polyvinyl alcohol, polycarbonate, polyethylene Examples thereof include plastic films such as terephthalate, polyurethane, and polyimide, wood, paper, and glass. The composition of the present invention is also useful for recoating a deteriorated coating film.

  These base materials can be subjected to surface treatment in advance for the purpose of adjusting the foundation, improving adhesion, sealing the porous base material, smoothing, patterning, and the like. Examples of the surface treatment for the metal base material include polishing, degreasing, plating treatment, chromate treatment, flame treatment, coupling treatment, and the like. Examples of the surface treatment for the plastic base material include blast treatment, Chemical treatment, degreasing, flame treatment, oxidation treatment, steam treatment, corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, ion treatment, and the like. Examples of surface treatments for inorganic ceramic base materials include polishing, Examples of the surface treatment for the wood base material include, for example, polishing, sealing, and insect repellent treatment. Examples of the surface treatment for the paper base material include, for example, sealing, Insect repellent treatment and the like, and as surface treatment for a deteriorated coating film, for example, keren can be mentioned. .

  Application | coating operation by the composition of this invention changes with the kind and state of a base material, and the application | coating method. For example, in the case of a metal-based substrate, if it is necessary to prevent rust, in addition to the coating composition of the present invention, a primer is used. In the case of an inorganic ceramic-based substrate, the characteristics of the substrate (surface roughness, impregnation, alkaline Etc.), the primer may be used because the concealability of the coating differs. In the case of recoating a deteriorated coating film, a primer is used when the deterioration of the old coating film is significant. In the case of other substrates such as plastic, wood, paper, glass, etc., a primer may or may not be used depending on the application.

  The kind of primer is not particularly limited, and any primer may be used as long as it has an effect of improving the adhesion between the base material and the composition, and is selected according to the kind of base material and the purpose of use. The primer can be used alone or in admixture of two or more, and may be an enamel containing a coloring component such as a pigment or a clear containing no coloring component.

  Examples of primer types include alkyd resins, amino alkyd resins, epoxy resins, polyesters, acrylic resins, urethane resins, fluororesins, acrylic silicone resins, acrylic resin emulsions, epoxy resin emulsions, polyurethane emulsions, and polyester emulsions. Can do. These primers can also be provided with various functional groups when adhesion between the substrate and the coating film under severe conditions is required. Examples of such a functional group include a hydroxyl group, a carboxyl group, a carbonyl group, an amide group, an amine group, a glycidyl group, an alkoxysilyl group, an ether bond, and an ester bond. Further, the primer may contain an ultraviolet absorber, an ultraviolet stabilizer and the like.

  In addition, the surface of the coating film formed from the composition of the present invention has, for example, US Pat. No. 3,986,997, US Pat. It is also possible to form a clear layer made of a siloxane resin-based paint such as a stable dispersion of colloidal silica and siloxane resin described in US Pat. No. 4,027,073.

Hereinafter, the embodiments of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.
In the examples and comparative examples, parts and% are based on weight unless otherwise specified.
Various measurements and evaluations in Examples and Comparative Examples were performed by the following methods.

(1) Storage stability It evaluated by the liquid external appearance and viscosity after storing at 40 degreeC for 3 months. The liquid appearance was evaluated according to the following criteria, and the viscosity evaluation was performed on the samples with ◯.
Liquid appearance evaluation criteria: Observed by visual observation and evaluated by ○ and ×.
○: No change from initial stage ×: Separation and sedimentation Viscosity evaluation criteria: Evaluated with B-type viscometer ◎: Viscosity change rate is less than initial value ± 20%
Δ: Viscosity change rate exceeds initial value ± 50% ×: Gelation

(2) Each composition was coated on quartz glass so as to have a dry film thickness of 2 μm, and then the visible light transmittance was measured and evaluated according to the following criteria.
A: The transmittance exceeds 80%.
○: Transmittance of 60-80%
Δ: Transmittance is less than 60%

(3) Warm water adhesion The sample which apply | coated each composition was immersed in 60 degreeC warm water, and adhesiveness was evaluated by the tape peeling test. The evaluation criteria are shown below.
◎: No tape peeling after 1 week immersion ○: No tape peeling after 4 days immersion, but tape peeling after 1 week immersion Δ: No tape peeling after 1 day immersion, but tape peeling after 4 days immersion ×: 1 day Tape stripping after immersion

(4) Hydrophilicity After irradiating the sample with a 1.0 mW / cm ² black light fluorescent lamp for 1 week, the contact angle (unit: degree) of water was measured.

(5) Weather resistance According to JIS K5400, an irradiation test was conducted for 3,000 hours with a sunshine weather meter, and visual appearance and adhesion were evaluated.
Visual appearance: Visual observation was performed and evaluated according to the following criteria.
○: No peeling of the film, no change from the initial stage ×: Peeling of the film Adhesion: A tape peeling test was conducted and evaluated according to the following criteria.
(Double-circle): There is no peeling of a film | membrane on the tape pasting part whole surface.
○: Less than 5% peeling at the tape applying part △: At least 5 and 50% peeling at the tape applying part ×: More than 50% peeling at the tape applying part

Reference Example 1 [Synthesis of component (b)]
In a reactor equipped with a reflux condenser and a stirrer, 55 parts of methyl methacrylate, 5 parts of 2-ethylhexyl acrylate, 5 parts of cyclohexyl methacrylate, 10 parts of γ-methacryloxypropyltrimethoxysilane, 20 parts of glycidyl methacrylate, 4- (meth) After adding and mixing 5 parts of acryloyloxy-2,2,6,6-tetramethylpiperidine, 75 parts of i-butyl alcohol, 50 parts of methyl ethyl ketone and 25 parts of methanol, the mixture was heated to 80 ° C. with stirring. A solution prepared by dissolving 3 parts of azobisisovaleronitrile in 8 parts of xylene was added dropwise over 30 minutes, and reacted at 80 ° C. for 5 hours. After cooling, 35 parts of methyl ethyl ketone was added to obtain a polymer solution (hereinafter referred to as “(b-1)”) having a solid content concentration of about 35% and Mw of 6,000.

Example 1 (Preparation of the composition of the present invention)
In a reactor equipped with a stirrer and a reflux condenser, 25 parts of methyltrimethoxysilane and 9 parts of dimetholdimethoxysilane as component (a), 50 parts of (b-1) having a solid content of 35% as component (b), (D) 7 parts of i-propyl alcohol as component, 3 parts of di-i-propoxy ethylacetoacetate aluminum 30% diluted solution as component (e) were added and mixed, and stirred at 50 ° C. The temperature was raised to. As the component (e), 7 parts of water was added in 30 minutes and reacted at 60 ° C. for 4 hours. Next, 1 part of acetylacetone as component (h) was added and stirred for 1 hour, and then cooled to room temperature. Next, under stirring, 150 parts of i-propyl alcohol and 150 parts of methyl ethyl ketone were added as component (e), and then ethyl silicate 48 (a tetrafunctional silane oligomer having a terminal ethoxy group; -1)) was added in an amount of 10 parts to obtain a composition I-1 of the present invention. Each of the prepared components is shown in Table 1 together with the storage stability evaluation result and the transparency evaluation result.

Examples 2-6
Example 1 was the same as Example 1 except that each composition was listed in Table 1. The results are shown in Table 1 together with the storage stability evaluation results and the transparency evaluation results.

c-1: Ethyl silicate 48 manufactured by Colcoat Co.
(Terminal ethoxy group tetrafunctional silane oligomer)
c-2: Silicon oligomer (X40-9225) manufactured by Shin-Etsu Chemical Co., Ltd.
(Methyl group-containing terminal alkoxy group silicon oligomer)
c-3: Silicone resin (YR3370) manufactured by Toshiba Silicone
[Trifunctional / bifunctional silicone resin containing methyl group (terminal silanol)]
IPA: isopropyl alcohol MIBK: methyl isobutyl ketone

Comparative Example 1
In a reactor equipped with a stirrer and a reflux condenser, 25 parts of methyltrimethoxysilane and 9 parts of dimetholdimethoxysilane as component (a), 50 parts of (b-1) having a solid content of 35% as component (b), (C) 10 parts of component (c-1) as component, 7 parts of i-propyl alcohol as component (e), 30% dilution of i-propyl alcohol of di-i-propoxyethylacetoacetate aluminum as component (d) 3 parts of the liquid was added and mixed, and the temperature was raised to 50 ° C. with stirring. As the component (e), 7 parts of water was added in 30 minutes and reacted at 60 ° C. for 4 hours. Next, 1 part of acetylacetone as component (h) was added and stirred for 1 hour, and then cooled to room temperature. Next, under stirring, 150 parts of i-propyl alcohol and 150 parts of methyl ethyl ketone were added as component (e) to obtain a composition (x-1) of a comparative example. As a result of storage stability evaluation, it was liquid appearance ×, viscosity ×, and transparency ○.

Preparation Example 1 [Preparation of Topcoat Composition (Coating Material Forming Photocatalyst Containing Layer)]
In a reactor equipped with a stirrer and a reflux condenser, 157 parts of water-dispersed titanium oxide having a solid concentration of about 24%, 8 parts of 3-glycidoxypropyltrimethoxysilane, terminal alkoxysilyl group / poly (oxyethylene / oxy) 11 parts of propylene) group-containing dimethyldimethoxysilane oligomer (Mw about 10,000) and 22 parts of i-propyl alcohol were added and mixed, and stirred at room temperature for 1 hour. Thereafter, 60 parts of methyltrimethoxysilane and 23 parts of the (b-B) component having a solid concentration of about 35% were added and stirred at room temperature for 1 hour. Next, 36 parts of i-propyl alcohol was added and mixed, followed by stirring at 30 ° C. for 1 hour. Thereafter, di-i-propoxyethyl acetoacetate aluminum: 2 parts dissolved in 18 parts of i-propyl alcohol were added and mixed, and a co-condensation reaction was carried out at 60 ° C. for 4 hours with stirring. After cooling to room temperature, 600 parts of i-propyl alcohol was added to obtain a composition ≡-1 having a solid concentration of about 10%.

Preparation Example 2
13 parts of an aqueous dispersion titanium oxide having a solid content concentration of 30%, 6 parts of ethyl silicate 48 manufactured by Colcoat Co., 30 parts of i-propanol-dispersed colloidal silica having a solid content concentration of about 10%, and 51 parts of i-propanol were added. An overcoating composition ≡-2 having a solid content of about 10% was obtained.

Examples 7-12
3 parts of i-butyl alcohol solution of dioctyltin dimaleate ester (solid content concentration of about 10%) was added to 100 parts of the coating composition of the present invention, and well-stirred was modified acrylic (Merinex 505, manufactured by Teijin DuPont). The same applies hereinafter) A surface-treated PET (polyethylene terephthalate) film was applied to a dry coating film of 1 μm and dried to obtain a cured product. The hot water adhesion of the obtained sample was evaluated. The results are shown in Table 2.

Comparative Example 2
3 parts of i-butyl alcohol solution of dioctyltin dimaleate ester (solid content concentration of about 10%) was added to 100 parts of the composition prepared in Comparative Example 1, and the well-stirred one was surface-treated with a modified acrylic resin. It apply | coated and dried so that it might become a dry coating film 1 micrometer on PET film, and it was set as the hardening body. The hot water adhesion of the obtained sample was evaluated. The results are shown in Table 2.

Examples 13-28
In each substrate listed in Table 3, 5 parts of i-butyl alcohol solution of dioctyltin dimaleate ester (solid content 15%) to 100 parts of the undercoat coating composition (I-1 to I-6) of the present invention Was added and stirred well (applied to a dry film thickness of 1 μm) and dried (80 ° C. × 10 minutes). Furthermore, 3 parts of i-propyl alcohol solution of dibutyltin diacetate (solid content 15%) was added to 100 parts of the coating composition for top coating, and the well-stirred coating was applied to a dry coating thickness of 0.1 μm and dried. (80 ° C. × 60 minutes) to obtain a cured product.
The obtained cured product was evaluated for hydrophilicity and weather resistance. The results are also shown in Table 3.

Comparative Examples 3-4
To each base material described in Table 4, 5 parts of i-butyl alcohol solution (solid content 15%) of dioctyltin dimaleate ester was added to 100 parts of (x-1) prepared in Comparative Example 1, and stirred well. The coated product was applied and dried (80 ° C. × 10 minutes) to a dry film thickness of 1 μm. Furthermore, 3 parts of i-propyl alcohol solution of dibutyltin diacetate (solid content 15%) was added to 100 parts of the coating composition for top coating, and the well-stirred coating was applied to a dry coating thickness of 0.1 μm and dried. (80 ° C. × 60 minutes) to obtain a cured product.
The obtained cured product was evaluated for hydrophilicity and weather resistance. The results are also shown in Table 4.

The coating composition of the present invention is useful as an undercoat for a photocatalyst-containing coating film (an intermediate layer between a substrate and a photocatalyst-containing coating film), and adheres to an organic substrate (organic properties) and radical deterioration with respect to the photocatalyst. It can satisfy the conflicting requirements of resistance (inorganic properties), can prevent deterioration of the substrate due to photocatalyst, and can provide a coating material with high hardness, excellent weather resistance and long-term durability adhesion, Suitable for undercoating.

Claims (10)

(b) in the presence of a polymer containing a hydrolyzable group and / or a silyl group having a silicon atom bonded to a hydroxyl group,
(A) The following general formula (1)
(R ¹ ) _n Si (OR ² ) _4-n (1)
(In the formula, when two R ¹ are present, they are the same or different and each represents a monovalent organic group having 1 to 8 carbon atoms; R ² is the same or different and is an alkyl group having 1 to 5 carbon atoms or 1 carbon atom; At least one selected from the group consisting of an organosilane represented by -6, n being an integer of 0 to 2, a hydrolyzate of the organosilane, and a condensate of the organosilane
An organic-inorganic hybrid polymer that has been previously hydrolyzed / condensed, and (c) an average composition formula R ³ _p Si (OR ⁴ ) _q O _{(4-pq) / 2} (wherein R ³ has 1 to 18 carbon atoms ₎ Wherein R ⁴ is a hydrogen group or one or more of monovalent organic groups having 1 to 4 carbon atoms, and p and q is a number satisfying 0 ≦ p ≦ 1.8, 0 <q <3.3, and 0 <p + q <4). . (A) component and (b) an organic-inorganic hybrid polymer obtained from component, component (a) (the product of complete hydrolysis and condensation terms) / (b) claims the weight ratio of the components is 5 / 95-60 / 40 2. A coating composition for undercoating of the photocatalyst-containing coating film according to 1. The coating composition for undercoating of the photocatalyst-containing coating film according to claim 1, wherein 0 ≦ p ≦ 1 in the average composition formula of component (c). The photocatalyst-containing composition according to any one of claims 1 to 3 , wherein in the average composition formula of component (c), one type of siloxane oligomer having p = 0 or 1 or a siloxane oligomer composed of two or more types is used as component (c). A coating composition for undercoating of a coating film. (C) In the average composition formula components for the undercoat of the photocatalyst-containing coating according to claim 1 or R ⁴ is one or more than one monovalent organic group having 1 to 4 carbon atoms Coating composition. Furthermore, the coating composition for undercoat of the photocatalyst containing coating film in any one of Claims 1-5 containing (f) inorganic filler. Furthermore, the coating composition for undercoat of the photocatalyst containing coating film in any one of Claims 1-6 containing an ultraviolet absorber (g). Claims applied when the photocatalyst-containing coating composition used for forming the upper layer photocatalyst-containing coating film is produced from water-dispersed titanium oxide having an average particle size of 0.2 µm or less. The coating composition for undercoat of the photocatalyst containing coating film in any one of 1-7 . The photocatalyst-containing coating composition used when forming the upper layer photocatalyst-containing coating film is produced using a titanium oxide powder having an average particle size of 0.2 μm or less or a titanium alkoxide as a raw material, The coating composition for undercoating of the photocatalyst-containing coating film according to any one of claims 1 to 7, which is applied in the case of a photocatalyst-containing coating composition containing 1% by weight or more of water per minute. A coating film obtained from the coating composition for undercoating of the photocatalyst-containing coating film according to any one of claims 1 to 9 is provided on a substrate, and a coating film made of the photocatalyst coating composition containing water is formed thereon. Structure.