JP2005230661A - Photocatalyst composition for visible light and coating film containing photocatalyst for visible light - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photocatalyst composition for visible light which exhibits a sufficient photocatalytic action under a circumstance with few spectral components of under 400 nm and with more visible light, for example, even in a chamber and in a vehicle chamber having UV cutting glass, which gives a coating film excellent in transparency, and of which a dispersion is excellent in storing stability, and to provide a highly transparent coating film containing a photocatalyst for visible light. <P>SOLUTION: The photocatalyst composition for visible light contains a specified oxide semiconductor, a titanium compound having a specified structure, a hydrolyzate of an organosilane having a specified structure and an organosiloxane oligomer having a specified structure. Then, the coating film is prepared from the photocatalyst composition for visible light. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a visible light photocatalyst composition exhibiting a photocatalytic action by visible light, particularly to a visible light photocatalyst composition useful for coating and a visible light photocatalyst-containing coating film comprising the visible light photocatalyst composition.

  Active research has been conducted on oxide semiconductors (a) having visible light photocatalytic activity, and many oxide semiconductor fine particles having a photocatalytic action with visible light have been proposed. Moreover, in order to immobilize the semiconductor fine particles at a relatively low temperature, a coating material using a siloxane resin as a binder is also provided, but the haze when the dry coating film is 0.1 μm exceeds 2, It is often inferior in transparency. In particular, when stored for a long period of time, there are problems such as thickening, gelation and particle sedimentation, and a transparent coating film cannot be obtained. A visible light photocatalyst composition with better dispersion stability and storage stability is desired. It was rare.

On the other hand, photocatalyst coating compositions are proposed in Patent Documents 1 and 2. However, when new semiconductor fine particles that have been specially treated to exhibit photocatalytic activity under visible light are used as photocatalyst fine particles, the surface characteristics of the semiconductor fine particles are different, and conventional coating compositions are thickened, gelled, In some cases, sedimentation of particles was caused, and sufficient dispersion stability could not be ensured, and a transparent coating film having a haze of 2 or less when the dried coating film was 0.1 μm could not be obtained. In particular, when the content of the semiconductor fine particles exhibiting a photocatalytic action under visible light exceeds 25% in the solid content, the decrease in the transparency becomes remarkable, and a transparent coating film with more excellent dispersion stability and storage stability is obtained. A visible light photocatalytic composition has been desired.

JP 2001-192616 A JP 2002-371234 A

  The present invention is intended to solve the problems associated with the prior art as described above, and has an environment with a small amount of spectral components of less than 400 nm and a large amount of visible light, for example, an indoor environment or a vehicle interior having an ultraviolet cut glass, The present invention aims to provide a visible light photocatalyst composition that exhibits sufficient photocatalytic activity and is excellent in coating film transparency and dispersion storage stability, and a visible light photocatalyst-containing coating film comprising the visible light photocatalyst composition. Yes.

The visible light photocatalyst composition and the visible light photocatalyst-containing coating film of the present invention are as follows.
That is, the first visible light photocatalyst composition according to the present invention is:
(A) an oxide semiconductor having visible light photocatalytic activity,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(In the formula, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more exist, they may be the same or different, and R ² represents an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ¹ and R ² are the same Or m may be an integer of 0 to 3)
At least one titanium compound selected from the group consisting of a titanium alcoholate represented by the formula (1) and a titanium acylate represented by the above formula (1) and a derivative thereof; )
R ³ _n Si (OR ⁴ ) _4-n (2)
(In the formula, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when a plurality of R ³ are present, they may be the same or different, and R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when there are a plurality of them, they may be the same or different, and R ³ and R ⁴ may be the same or different; n is an integer of 0 to 3)
At least one silane compound selected from the group consisting of organosilanes and derivatives thereof,
And having photocatalytic activity under irradiation with visible light of 400 nm or more.

Further, the second visible light photocatalyst composition according to the present invention is (a) an oxide semiconductor having visible light photocatalytic activity,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(In the formula, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more exist, they may be the same or different, and R ² represents an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ¹ and R ² are the same Or m may be an integer of 0 to 3)
And at least one titanium compound selected from the group consisting of a titanium alcoholate represented by the formula (1) and a titanium acylate represented by the formula (1) and a derivative thereof, and (d) a Si-O bond. Having a weight average molecular weight of 300 to 100,000, and the following formula (3)
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(In the formula, R ⁵ and R ⁶ represent an alkyl group having 1 to 5 carbon atoms, which may be the same or different, and R ⁷ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. , P and q are numbers such that the value of p + q is 2 to 50)
An organosiloxane oligomer containing a structure represented by:
And having photocatalytic activity under irradiation with visible light of 400 nm or more.

Furthermore, the third visible light photocatalyst composition according to the present invention comprises (a) an oxide semiconductor having visible light photocatalytic activity,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(In the formula, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more exist, they may be the same or different, and R ² represents an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ¹ and R ² are the same Or m may be an integer of 0 to 3)
And at least one titanium compound selected from the group consisting of a titanium acylate represented by the above formula (1) and a derivative thereof,
(C) The following general formula (2)
R ³ _n Si (OR ⁴ ) _4-n (2)
(In the formula, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when a plurality of R ³ are present, they may be the same or different, and R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when there are a plurality of them, they may be the same or different, and R ³ and R ⁴ may be the same or different; n is an integer of 0 to 3)
And at least one silane compound selected from the group consisting of organosilanes and derivatives thereof, and (d) having a Si—O bond, a weight average molecular weight of 300 to 100,000, and the following formula: (3)
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(In the formula, R ⁵ and R ⁶ represent an alkyl group having 1 to 5 carbon atoms, which may be the same or different, and R ⁷ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. , P and q are numbers such that the value of p + q is 2 to 50)
An organosiloxane oligomer containing a structure represented by:
And having photocatalytic activity under irradiation with visible light of 400 nm or more.

Further, in the fourth visible light photocatalyst composition according to the present invention, in the first to third visible light photocatalyst compositions according to the present invention, (a) an oxide semiconductor having visible light photocatalytic activity is measured for diffuse reflection spectrum. The absorbance at 400 nm measured by the above is preferably 0.05 or more.
Further, in the fifth visible light photocatalyst composition according to the present invention, in the first to fourth visible light photocatalyst compositions according to the present invention, (a) an oxide semiconductor having visible light photocatalytic activity is oxidized with a brookite type. It is preferably at least one selected from the group consisting of titanium, ion-implanted titanium oxide, plasma-treated titanium oxide, oxygen-deficient titanium oxide, nitrogen-doped titanium oxide, sulfur-doped titanium oxide, and platinum-supported titanium oxide. .
The sixth visible light photocatalyst composition according to the present invention preferably further contains (f) a catalyst in the first to fifth visible light photocatalyst compositions according to the present invention.
Further, in the seventh visible light photocatalyst composition according to the present invention, the first to sixth visible light photocatalyst compositions according to the present invention have a haze of 2 or less when a dry coating film having a thickness of 0.1 μm is formed. It is preferable that

The visible light photocatalyst-containing coating film according to the present invention can be obtained from the visible light photocatalyst composition.

According to the present invention, the coating film exhibits a sufficient photocatalytic action and excellent transparency even in an environment having a small amount of spectral components of less than 400 nm and a large amount of visible light, for example, an indoor environment or a vehicle interior having an ultraviolet cut glass. In addition, a photocatalyst composition excellent in storage stability of the dispersion can be obtained. Moreover, the coating film obtained from such a photocatalyst composition can be suitably used for a wide range of applications utilizing photocatalytic performance such as organic matter decomposition.

Hereinafter, each component of the visible light photocatalyst composition according to the present invention will be described in detail.
(A) Oxide semiconductor having visible light photocatalytic activity:
The oxide semiconductor having visible light photocatalytic activity used in the present invention is an oxide semiconductor (hereinafter referred to as “oxide semiconductor (a)”) from which a visible light photocatalytic composition having photocatalytic activity can be obtained under irradiation with visible light of 400 nm or more. If it says, it will not specifically limit.

Examples of the oxide semiconductor (a) include titanium oxide, tin oxide, zinc oxide, strontium titanate, tungsten oxide, zirconium oxide, niobium oxide, iron oxide, copper oxide, iron titanate, nickel oxide, and bismuth oxide. Examples include oxide semiconductors that have been subjected to a modification treatment so as to act on visible light. More preferable examples include brookite type titanium oxide, ion-implanted type titanium oxide, plasma-treated titanium oxide, oxygen-deficient titanium oxide, nitrogen-doped titanium oxide, sulfur-doped titanium oxide, platinum-supported titanium oxide, and the like.

These oxide semiconductors (a) have an absorbance at 400 nm measured by diffuse reflection spectrum measurement of 0.05 or more, more preferably 0.07 or more, and particularly preferably 0.10 or more. The photocatalytic activity of the photocatalytic composition obtained by using the semiconductor (a) is effectively expressed under visible light irradiation. The absorbance by the diffuse reflection spectrum measurement can be measured by, for example, a spectrophotometer V-570 manufactured by JASCO Corporation.

The form of the oxide semiconductor (a) is not limited, but for example, powder, an aqueous sol or colloid dispersed in water, or an organic solvent sol dispersed in a polar solvent such as alcohol or a nonpolar solvent such as toluene. Or the form of a colloid etc. is mentioned. When the oxide semiconductor (a) is an organic solvent-based sol or colloid, it may be further diluted with water or an organic solvent depending on its dispersibility, and the oxide semiconductor may be used to improve dispersibility. The surface of (a) may be treated. The form of the oxide semiconductor (a) is appropriately determined according to the desired properties of the coating film. When the oxide semiconductor (a) is in the form of sol or colloid, the solid content concentration is preferably 40% by weight or less. The primary particle diameter of the oxide semiconductor (a) is preferably 200 nm or less, particularly preferably 100 nm or less. When the primary particle size exceeds 200 nm, the transparency is inferior, and when the coating film has a thickness of 0.1 μm, the haze may exceed 2.

  In the visible light photocatalyst composition, the oxide semiconductor (a) is 1% to 90% by weight, preferably 15 to 85% by weight, more preferably 25 to 80% by weight based on the total solid content of the composition. It is desirable to contain in the amount of%. If the amount of the oxide semiconductor (a) is less than the lower limit with respect to the total solid content of the visible light photocatalyst composition, the visible light photocatalytic action may not be exhibited, and if the upper limit is exceeded, a coating film is formed. When doing so, choking or the like may occur, and the film forming property may be inferior.

(B) Titanium compound:
The titanium compound (b) used in the present invention has the following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(In the formula, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more exist, they may be the same or different, and R ² represents an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ¹ and R ² are the same Or m may be an integer of 0 to 3)
And at least one titanium compound selected from the group consisting of the titanium acylate represented by the above formula (1) and the derivative thereof.

Examples of the titanium alcoholate derivative include a hydrolyzate of the titanium alcoholate, a condensate of the titanium alcoholate, a chelate compound of the titanium alcoholate, a hydrolyzate of the chelate compound of the titanium alcoholate, and the titanium alcoholate. And a condensate of the above chelate compound.
Further, the titanium acylate derivative includes a hydrolyzate of the titanium acylate, a condensate of the titanium acylate, a chelate compound of the titanium acylate, a hydrolyzate of the chelate compound of the titanium acylate, and the titanium. Examples include condensates of acylate chelate compounds.

In the above formula (1), R ¹ is an organic group having 1 to 8 carbon atoms, specifically, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec- Alkyl groups such as butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group;
Acyl groups such as formyl group, acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group, trioyl group, caproyl group;
Examples thereof include a vinyl group, an allyl group, a cyclohexyl group, a phenyl group, an epoxy group, a glycidyl group, a (meth) acryloxy group, a ureido group, an amide group, a fluoroacetamide group, and an isocyanate group.

Furthermore, examples of R ¹ include substituted derivatives of the above organic groups. Examples of the substituent of 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, a (meth) acryloxy group, A ureido group, an ammonium base, etc. are mentioned. However, the number of carbon atoms of R ¹ composed of these substituted derivatives is preferably 8 or less including the carbon atoms in the substituent. When a plurality of R ¹ are present in the formula (1), they may be the same or different.

As R ² which is an alkyl group having 1 to 6 carbon atoms, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t -Butyl group, n-hexyl group, n-heptyl group, etc. are mentioned.

Examples of R ² which is an acyl group having 1 to 6 carbon atoms include formyl group, acetyl group, propionyl group, butyryl group, valeryl group, trioyl group, caproyl group and the like.
When a plurality of R ² are present in the formula (1), they may be the same or different.

  The chelate compound of titanium alcoholate is selected from the group consisting of the titanium alcoholate and β-diketones, β-ketoesters, hydroxycarboxylic acid, hydroxycarboxylate, hydroxycarboxylic acid ester, ketoalcohol and aminoalcohol. It can be obtained by reacting with at least one compound (hereinafter also referred to as chelating agent). A chelate compound of titanium acylate can be obtained by reacting the titanium acylate with the chelating agent. Of these chelating agents, β-diketones or β-ketoesters are preferably used. More specifically, acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate-sec-butyl, acetoacetate-t-butyl 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane-dione, 5-methyl-hexane-dione, etc. Used.

  Specific examples of titanium alcoholate and titanium alcoholate chelate compounds include tetra-i-propoxytitanium, tetra-n-butoxytitanium, tetra-t-butoxytitanium, and di-i-propoxybis (ethylacetoacetate). Titanium, di-i-propoxy bis (acetylacetate) titanium, di-i-propoxy bis (lactate) titanium, di-i-propoxy bis (acetylacetonato) titanium, di-n-butoxy bis (tri Ethanolaminato) titanium, di-n-butoxy bis (acetylacetonato) titanium, tetrakis (2-ethylhexyloxy) titanium and the like.

Of these, tetra-i-propoxytitanium, tetra-n-butoxytitanium, tetra-t-butoxytitanium, di-i-propoxybis (acetylacetonato) titanium, di-n-butoxybis (acetylacetonate) ) Titanium is preferred.
Specific examples of titanium acylate and titanium acylate chelate compounds include dihydroxy / titanium dibutyrate, di-i-propoxy / titanium diacetate, bis (acetylacetonate) / titanium diacetate, and bis (acetylacetate). Nato) -titanium dipropionate, di-i-propoxy-titanium dipropionate, di-i-propoxy-titanium dimalonate, di-i-propoxy-titanium dibenzoylate, di-n-butoxy-zirconium diacetate , Di-i-propyl aluminum monomalonate and the like. Of these, dihydroxy titanium dibutyrate and di-i-propoxy titanium diacetate are preferred.

Titanium alcoholate hydrolyzate, titanium alcoholate chelate hydrolyzate, titanium acylate hydrolyzate, or titanium acylate chelate hydrolyzate is contained in titanium alcoholate or titanium acylate at least one of oR ² groups need only be hydrolysed, for example those in which one oR ² group is hydrolyzed, those two or more oR ² group is hydrolyzed, or a mixture thereof May be.

  Titanium alcoholate condensate, titanium alcoholate chelate condensate, titanium acylate condensate, and titanium acylate chelate condensate are titanium alcoholate, titanium alcoholate chelate, titanium acylate, respectively. The Ti—OH group in the hydrolyzate produced by hydrolysis of the rate and the chelate compound of titanium acylate is condensed to form a Ti—O—Ti bond. In the present invention, it is not necessary that all of the Ti—OH groups are condensed, and the condensate is obtained by condensing a small part of Ti—OH groups, and most (including all) Ti—OH groups. In addition, a mixture of a condensate in which a Ti—OR group and a Ti—OH group are mixed is also included.

In the present invention, the titanium compound (b) preferably uses the condensate in order to control the reactivity and suppress gelation, and the condensation degree of the condensate ranges from a dimer to a 20-mer. More preferred is a condensation degree of 2 to 10 mer. This condensate is composed of titanium alcoholate, titanium alcoholate chelate compound, titanium acylate, and one compound selected from the group consisting of titanium acylate chelate compounds or a mixture of two or more titanium compounds. Those previously hydrolyzed and condensed may be used, or commercially available condensates may be used. In addition, a titanium alcoholate or a titanium acylate condensate may be used as it is, a product obtained by hydrolyzing a part or all of the OR ² group contained in the condensate, or the chelate obtained by chelating the condensate. You may use as a condensate of the chelate compound of titanium alcoholate or titanium acylate obtained by making it react with an agent.

  Examples of commercially available titanium alcoholate condensates (from dimer to 10-mer) include A-10, B-2, B-4, B-7, and B-10 manufactured by Nippon Soda Co., Ltd. Such a titanium compound (b) may be used individually by 1 type, or 2 or more types may be mixed and used for it.

The amount of the titanium compound (b) used in the present invention is 1 to 50 parts by weight, preferably 2 to 45 parts by weight in terms of complete hydrolysis condensate, based on 100 parts by weight of the solid content of the oxide semiconductor (a). More preferably, the amount is 3 to 40 parts by weight. Here, the completely hydrolyzed condensate means that the OR ² group in the formula (1) is 100% hydrolyzed to become a Ti—OH group, and further, the Ti—OH group is completely condensed to form a Ti—O—Ti structure. Is what formed. These titanium compounds (b) adsorb or bind to the surface of the oxide semiconductor (a), improve the affinity of the oxide semiconductor (a) to the solvent, and reduce the dispersed particle size and dispersibility. It is thought that there is an action which raises.

(C) Silane compound:
The silane compound (c) used in the present invention has the following formula (2)
R ³ _n Si (OR ⁴ ) _4-n (2)
(In the formula, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when a plurality of R ³ are present, they may be the same or different, and R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when there are a plurality of them, they may be the same or different, and R ³ and R ⁴ may be the same or different; n is an integer of 0 to 3)
At least one silane compound selected from the group consisting of an organosilane (hereinafter referred to as “organosilane (2)”) and derivatives thereof.

Examples of the organosilane (2) derivative include hydrolyzate of organosilane (2) and condensate of organosilane (2).
The silane compound (c) used in the present invention is at least one silane compound selected from the group consisting of organosilane (2), hydrolyzate of organosilane (2), and condensate of organosilane (2). Of these three silane compounds, only one silane compound may be used, any two silane compounds may be mixed, or all three silane compounds may be mixed. May be used.

In the above formula (2), R ³ is a monovalent organic group having 1 to 8 carbon atoms, specifically, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group. Alkyl groups such as i-butyl group, sec-butyl group, t-butyl group, n-hexyl group, n-heptyl group, n-octyl group and 2-ethylhexyl group;
Acyl groups such as acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group, trioyl group, caproyl group;
Examples thereof include a vinyl group, an allyl group, a cyclohexyl group, a phenyl group, an epoxy group, a glycidyl group, a (meth) acryloxy group, a ureido group, an amide group, a fluoroacetamide group, and an isocyanate group.

Furthermore, examples of R ³ include substituted derivatives of the above organic groups. Examples of the substituent of the substituted derivative of R ³ 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, a (meth) acryloxy group, A ureido group, an ammonium base, etc. are mentioned. However, the number of carbon atoms of R ³ composed of these substituted derivatives is preferably 8 or less including the carbon atoms in the substituent. When a plurality of R ³ are present in the formula (2), they may be the same or different.

As R ⁴ which is an alkyl group having 1 to 5 carbon atoms, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group, 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. are mentioned, for example.

Moreover, as for R < ⁴ > which is a C1-C6 acyl group, the C1-C6 acyl group as described in (b) titanium compound is mentioned. When a plurality of R ⁴ are present in the formula (2), they may be the same or different.
Specific examples of such organosilane (2) include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, and tetra-n-butoxysilane;
Methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, n- Butyltrimethoxysilane, n-butyltriethoxysilane, n-pentyltrimethoxysilane, n-hexyltrimethoxysilane, n-heptyltrimethoxysilane, n-octyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, Cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-hydroxyethyltrimethoxy Silane, 2-hydroxyethyltriethoxysilane, 2-hydroxypropyltrimethoxysilane, 2-hydroxypropyltriethoxysilane, 3-hydroxypropyltrimethoxysilane, 3-hydroxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycid Cypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- Trialkoxysilanes such as (meth) acrylicoxypropyltriethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane;
Dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-n-propyldimethoxysilane, di-n-propyldiethoxysilane, di-i-propyldimethoxysilane, di-i-propyldiethoxy Silane, di-n-butyldimethoxysilane, di-n-butyldiethoxysilane, di-n-pentyldimethoxysilane, di-n-pentyldiethoxysilane, di-n-hexyldimethoxysilane, di-n-hexyldi Ethoxysilane, di-n-heptyldimethoxysilane, di-n-heptyldiethoxysilane, di-n-octyldimethoxysilane, di-n-octyldiethoxysilane, di-n-cyclohexyldimethoxysilane, di-n-cyclohexyl Diethoxysilane, diphenyl Silane, dialkoxy silanes such as diphenyl diethoxy silane;
Monoalkoxysilanes such as trimethylmethoxysilane, trimethylethoxysilane, triethylmethoxysilane, triethylethoxysilane;
Examples thereof include methyltriacetyloxysilane and dimethyldiacetyloxysilane.

Of these, trialkoxysilanes and dialkoxysilanes are preferable, and methyltrimethoxysilane and methyltriethoxysilane are more preferable as trialkoxysilanes, and dimethyldimethoxysilane and dimethyldisilane are preferable as dialkoxysilanes. Ethoxysilane is preferred.
As the organosilane (2) used in the present invention, the above organosilane (2) may be used alone or in combination of two or more. For example, trialkoxysilane alone or a mixture of trialkoxysilane 40 to 95 mol% and dialkoxysilane 60 to 5 mol% is particularly preferably used. By using dialkoxysilane and trialkoxysilane in combination, the resulting coating film can be softened and alkali resistance can be improved.

In the present invention, organosilane (2) may be used as it is as silane compound (b), but hydrolyzate and / or condensate of organosilane (2) can be used.
The hydrolyzate of organosilane (2) is sufficient if at least one of 1-4 OR ⁴ groups contained in organosilane (2) is hydrolyzed, for example, one OR ⁴ group. In which two or more OR ⁴ groups are hydrolyzed, or a mixture thereof.

  The condensate of organosilane (2) is a product in which silanol groups in the hydrolyzate produced by hydrolysis of organosilane (2) are condensed to form Si—O—Si bonds. In the present invention, it is not necessary that all of the silanol groups are condensed, and the condensate may be one obtained by condensing a small part of silanol groups, one containing most (including all) silanol groups, And mixtures thereof.

  Such hydrolyzate and / or condensate of organosilane (2) can be produced by hydrolyzing and condensing organosilane (2) in advance. As will be described later, when preparing the visible light photocatalyst composition, hydrolyzate and / or condensate of organosilane (2) is prepared by hydrolyzing and condensing organosilane (2) and water. You can also In addition, you may add this water independently, and you may use the oxide semiconductor (a) or the water contained in the (e) water or organic solvent mentioned later. The amount of water when added independently is usually 0.5 to 5 mol, preferably 0.7 to 3 mol, particularly preferably 0.7 to mol, per 1 mol of organosilane (2). desirable.

Such a condensate of organosilane (2) has a polystyrene-reduced weight average molecular weight (hereinafter referred to as “Mw”) by GPC method, preferably 300 to 100,000, more preferably 500 to 50,000. A condensate is used.
As the silane compound (c) in the present invention, the above silane compound may be prepared, or a commercially available silane compound may be used. Commercially available silane compounds include MKC silicate manufactured by Mitsubishi Chemical Corporation, ethyl silicate manufactured by Colcoat, silicone resin manufactured by Toray Dow Corning Silicone, silicon resin manufactured by GE Toshiba Silicone, Shin-Etsu Chemical Co., Ltd. Silicone resin, hydroxyl group-containing polydimethylsiloxane manufactured by Dow Corning Asia, and silicon oligomer manufactured by Nihon Unicar. These commercially available silane compounds may be used as they are, or may be used after being condensed.

Such a silane compound (c) may be used individually by 1 type, or 2 or more types may be mixed and used for it.
In the present invention, the silane compound (c) is 5% by weight or more in terms of complete hydrolysis condensate based on the solid content of the visible light photocatalyst composition excluding the oxide semiconductor (a), preferably It is desirable to use it in an amount of 10% by weight or more, more preferably 20% by weight or more. Here, the completely hydrolyzed condensate is a product in which the OR ⁴ group in the formula (2) is hydrolyzed to become a Si—OH group, and the Si—OH group is completely condensed to form a siloxane structure. Say. When the content of the silane compound (c) is less than the above lower limit, the formed coating film is brittle, and choking or the like may occur.

(D) Organosiloxane oligomer:
The organosiloxane oligomer (d) used in the present invention has a Si—O bond, has a weight average molecular weight of 300 to 100,000, and has the following formula (3) in the side chain and / or terminal.
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(In the formula, R ⁵ and R ⁶ each independently represent an alkyl group having 1 to 5 carbon atoms, R ⁷ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and p and q are respectively Independently, the value of p + q is 2 to 50)
The structure represented by these is contained.

  Examples of the functional group represented by the above formula (3) include polyoxyalkylene groups such as a polyoxyethylene group, a polyoxypropylene group, and a poly (oxyethylene / oxypropylene) group. When the organosiloxane oligomer (d) contains such a functional group, the polyoxyalkylene group portion in the functional group is easily adsorbed to the oxide semiconductor (a), and the dispersion stability of the oxide semiconductor (a) Is thought to improve.

The main chain of the organosiloxane oligomer (d) may be substituted with a hydroxyl group, a halogen atom, or a functional group containing an organic group having 1 to 15 carbon atoms.
Examples of the halogen atom include fluorine and chlorine.
As an organic group having 1 to 15 carbon atoms, an alkyl group, acyl group, alkoxyl group, alkoxysilyl group, vinyl group, allyl group, acetoxyl group, acetoxysilyl group, cycloalkyl group, phenyl group, glycidyl group, (meth) acrylic Examples thereof include an oxy group, a ureido group, an amide group, a fluoroacetamide group, and an isocyanate group.

  Examples of the alkyl group having 1 to 15 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, and n-hexyl. Group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, hexadecyl group, heptadecyl group, octadecyl group, 2-ethylhexyl group, etc. It is done.

Examples of the acyl group having 1 to 15 carbon atoms include formyl group, acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group, and toluoyl group.
Examples of the alkoxyl group having 1 to 15 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.
Examples of the alkoxysilyl group having 1 to 15 carbon atoms include a methoxysilyl group, an ethoxysilyl group, a propoxysilyl group, and a butoxysilyl group.

  These groups may be partially hydrolyzed / condensed or substituted derivatives. Examples of substituents of substituted derivatives include halogen atoms, substituted or unsubstituted amino groups, hydroxyl groups, mercapto groups, isocyanate groups, glycidoxy groups, 3,4-epoxycyclohexyl groups, (meth) acryloxy groups, ureido groups, and ammonium. Examples include bases and ketoester groups.

  Of these, the organosiloxane oligomer (d) containing a structure in which a silicon atom of a silyl group is bonded to a hydrolyzable group and / or a hydroxyl group is particularly preferably used. For example, a chlorosilane condensate or an alkoxysilane condensate is used. Used. Such an organosiloxane oligomer (d) is immobilized by cocondensation with the titanium compound (b) and / or the silane compound (c) when the visible light photocatalyst composition according to the present invention is cured. A stable coating film can be obtained.

  The weight average molecular weight (hereinafter also referred to as “Mw”) in terms of polystyrene by the GPC method of the organosiloxane oligomer (d) is 300 to 100,000, preferably 600 to 50,000. If the weight average molecular weight is less than the above lower limit, the resulting coating film may not have sufficient flexibility, and if it exceeds the above upper limit, the resulting coating composition may not have sufficient storage stability. is there.

  In the present invention, the organosiloxane oligomer (d) may be used alone or in combination of two or more. As an organosiloxane oligomer (d) in which two or more kinds are mixed, a mixture of an organosiloxane oligomer having Mw = 400 to 2,800 and an organosiloxane oligomer having Mw = 3,000 to 50,000, or 2 having different functional groups Mention may be made of mixtures of different organosiloxane oligomers.

  In the present invention, a commercially available organosiloxane oligomer can be used as the organosiloxane oligomer (d). For example, a modified silicone oil manufactured by Toray Dow Corning Silicone, a modified silicone oil manufactured by GE Toshiba Silicone Examples thereof include silicone oil, modified silicone oil manufactured by Shin-Etsu Chemical Co., Ltd., and modified silicon oligomer MAC-2101 manufactured by Nihon Unicar. These organosiloxane oligomers may be used as they are or after being condensed.

  The amount of the organosiloxane oligomer (d) used in the present invention is 1 to 200 parts by weight, preferably 5 to 100 parts by weight, more preferably 10 to 10 parts by weight based on 100 parts by weight of the solid content of the oxide semiconductor (a). 80 parts by weight is desirable. If the amount of the organosiloxane oligomer (d) is less than the above lower limit, sufficient dispersion stability may not be obtained, and if the amount exceeds the above upper limit, the formed coating film may be brittle and choking may occur. .

(E) Water and / or organic solvent:
The visible light photocatalyst composition according to the present invention preferably contains (e) water and / or an organic solvent. As the organic solvent, known organic solvents can be used, and examples thereof include alcohols, aromatic hydrocarbons, ethers, ketones, and esters.

  More specifically, as alcohols, 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, and aromatic hydrocarbons as Examples include benzene, toluene, xylene, etc. Examples of ethers include tetrahydrofuran, dioxane, etc. Examples of ketones include acetone, methyl ethyl ketone, methyl isobutyl ketone, and diisobutyl ketone. Examples of esters include ethyl acetate, propyl acetate, butyl acetate, propylene carbonate, methyl lactate, ethyl lactate, normal propyl lactate, isopropyl lactate, Examples include methyl 3-ethoxypropionate and ethyl 3-ethoxypropionate. These organic solvents may be used individually by 1 type, or 2 or more types may be mixed and used for them.

(F) Catalyst:
The visible light photocatalyst composition according to the present invention preferably contains a catalyst (f) in order to promote hydrolysis / condensation reaction of the silane compound (c), the organosiloxane oligomer (d) and the like. As the catalyst (f) used in the present invention, an acidic compound, an alkaline compound, a salt compound, an amine compound, an organometallic compound and / or a partial hydrolyzate thereof (hereinafter referred to as an organometallic compound and / or a partial hydrolyzate thereof are summarized. And “organic metal compounds”).

Examples of the acidic compound include acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, alkyl titanic acid, p-toluenesulfonic acid, and phthalic acid, and among these, acetic acid is preferable.
Examples of the alkaline compound include sodium hydroxide and potassium hydroxide, and among these, sodium hydroxide is preferable.

Examples of the salt compound include naphthenic acid, octylic acid, nitrous acid, sulfurous acid, aluminate, and alkali metal salts such as carbonic acid.
Examples of the amine compound include ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, piperidine, piperazine, m-phenylenediamine, p-phenylenediamine, ethanolamine, triethylamine, 3-aminopropyl trimethoxy. Silane, 3-aminopropyl-triethoxysilane, 3- (2-aminoethyl) -aminopropyl-trimethoxysilane, 3- (2-aminoethyl) -aminopropyl-triethoxysilane, 3- (2-aminoethyl) ) -Aminopropyl-methyl-dimethoxysilane, 3-anilinopropyl-trimethoxysilane, alkylamine salts, and quaternary ammonium salts. Various modified amines used as a curing agent for epoxy resins can also be used. Of these, 3-aminopropyl / trimethoxysilane, 3-aminopropyl / triethoxysilane, and 3- (2-aminoethyl) -aminopropyl / trimethoxysilane are preferable.

Examples of the organometallic compounds include the following formula (4):
M (OR ⁸ ) _r (R ⁹ COCHCOR ¹⁰ ) _s (4)
(In the formula, M represents at least one metal atom selected from the group consisting of zirconium, titanium and aluminum, and R ⁸ and R ⁹ are each independently a methyl group, an ethyl group, or an n-propyl group. , Monovalent hydrocarbon having 1 to 6 carbon atoms such as i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, cyclohexyl group and phenyl group R ¹⁰ represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, or a sec-butoxy group. Represents an alkoxyl group having 1 to 16 carbon atoms such as t-butoxy group, lauryloxy group, stearyloxy group, and r and s are each independently an integer of 0 to 4, and (r + s) = (M Atoms Value))
(Hereinafter referred to as “organometallic compound (4)”),
A tetravalent tin organometallic compound in which one or two alkyl groups having 1 to 10 carbon atoms are bonded to one tin atom (hereinafter referred to as “organotin compound”), or
These partial hydrolysates are exemplified.

Moreover, the above-described titanium compound (b) can be used as the organometallic compounds.
Examples of the organometallic compound (4) include tetra-n-butoxyzirconium, tri-n-butoxyethylacetoacetatezirconium, di-n-butoxybis (ethylacetoacetate) zirconium, n-butoxytris (ethylacetoacetate). Organic zirconium compounds such as acetate) zirconium, tetrakis (n-propylacetoacetate) zirconium, tetrakis (acetylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium;
Organic titanium compounds such as tetra-i-propoxy titanium, di-i-propoxy bis (ethylacetoacetate) titanium, di-i-propoxy bis (acetylacetate) titanium, di-i-propoxy bis (acetylacetone) titanium ;
Tri-i-propoxyaluminum, di-i-propoxyethyl acetoacetate aluminum, di-i-propoxy acetylacetonate aluminum, i-propoxy bis (ethylacetoacetate) aluminum, i-propoxy bis (acetylacetonate) And organoaluminum compounds such as aluminum, tris (ethylacetoacetate) aluminum, tris (acetylacetonato) aluminum, monoacetylacetonatobis (ethylacetoacetate) aluminum.

  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 thereof is preferably used.

As an organic tin compound, for example,
(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) Sn (} OCOC 11 H 23) 3,
(C ₄ H ₉ ) 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 ) Sn = S
｜
S
｜
(C ₄ H ₉ ) 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 SnCl
｜
S
｜
(C ₄ H ₉ ) ₂ SnCl
Chloride-type organotin compounds such as;
Reaction of organotin oxides such as (C ₄ H ₉ ) ₂ SnO, (C ₈ H ₁₇ ) ₂ SnO, and ester compounds such as silicates, dimethyl maleate, diethyl maleate and dioctyl phthalate Product;
Etc.

Such a catalyst (f) may be used singly or in combination of two or more, or may be used by mixing with a zinc compound or other reaction retarder.
The catalyst (f) may be blended in the step of preparing the visible light photocatalyst composition according to the present invention, or may be blended in the visible light photocatalyst composition in the step of forming a coating film. You may mix | blend both in the preparation process of a visible light photocatalyst composition, and the formation process of a coating film.

The amount of the catalyst (f) used in the present invention is usually 10 moles or less, preferably 0.001 to 7 moles, more preferably 0.8 moles per mole of OR ⁴ group contained in the silane compound (c). 001-5 mol is desirable. When the amount of the catalyst (f) exceeds the above upper limit, the storage stability of the visible light photocatalyst composition may be lowered, or cracks may be generated in the coating film.

  The catalyst (f) promotes hydrolysis / condensation reaction of the silane compound (c), the organosiloxane oligomer (d) and the like. Therefore, by using the catalyst (f), for example, the molecular weight of the polysiloxane resin produced by the polycondensation reaction of the organosiloxane oligomer (d) is increased, and the curing rate of the resulting coating film is improved. A coating film excellent in durability and the like can be obtained, and the coating film can be made thicker, so that the painting work is facilitated.

(G) Stability improver:
The visible light photocatalyst composition according to the present invention may contain a stability improver (g) in order to improve storage stability and the like as necessary. The stability improver (g) used in the present invention is represented by the following formula (5).
R ¹¹ COCH ₂ COR ¹² (5)
(In the formula, R ¹¹ is methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, cyclohexyl group) R 1 represents a monovalent hydrocarbon group having 1 to 6 carbon atoms such as a group or a phenyl group, and R ¹² represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a methoxy group, an ethoxy group, n -Represents an alkoxyl group having 1 to 16 carbon atoms such as propoxy group, i-propoxy group, n-butoxy group, sec-butoxy group, t-butoxy group, lauryloxy group, stearyloxy group)
At least one compound selected from the group consisting of β-diketones, β-ketoesters, carboxylic acid compounds, dihydroxy compounds, amine compounds and oxyaldehyde compounds.

  Examples of such a stability improver (g) 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, methi Nin, such as salicylic aldehyde, and the like. Of these, acetylacetone and ethyl acetoacetate are preferred.

Such a stability improver (g) is particularly preferably used when an organometallic compound is used as the titanium compound (b) or the catalyst (f). Moreover, a stability improver (g) may be used individually by 1 type, or may mix and use 2 or more types.
By using the stability improver (g), the stability improver (g) is coordinated to the metal atom of the organometallic compound, and this coordination is achieved by the silane compound (c) or the organosiloxane oligomer (d). It is considered that the storage stability of the resulting visible light photocatalyst composition can be further improved by appropriately adjusting the promoting action of the organometallic compounds for the cocondensation reaction.

  The amount of the stability improver (g) used in the present invention is usually 2 moles or more, preferably 3 to 20 moles per mole of the organometallic compound of the organometallic compounds. When the amount of the stability improver (g) is less than the above lower limit, the visible light photocatalyst composition having a high solid content concentration may be insufficient in improving the storage stability of the resulting composition.

(H) Filler:
In the visible light photocatalyst composition according to the present invention, it is also preferable to add and disperse a filler as necessary in order to color the coating film to be obtained and to increase the thickness of the coating film.
Fillers used in the present invention include water-insoluble organic pigments and inorganic content; ceramics, metals or alloys other than particulate, fibrous or scale-like pigments, and oxides, hydroxides and carbides of these metals , Nitrides and sulfides.
Specifically, iron, copper, aluminum, nickel, silver, zinc, ferrite, carbon black, stainless steel, silicon dioxide, titanium oxide for pigments, 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, Shale green, Green earth, Manganese green, Pigment green, Ultramarine, Bitumen, Pigment blue, Rock ultramarine, Cobalt blue, Cerulean blue, Copper borate, Molybdenum blue , Copper sulfide, cobalt purple, mars purple, manga 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, Chrome Vermilion , 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, bone Black, diamond black, thermatomic black, vegetable black, potassium titanate whisker, molybdenum disulfide and the like.
These fillers can be used alone or in admixture of two or more.
The amount of the filler used is preferably 300 parts by weight or less with respect to 100 parts by weight of the total solid content of the visible light photocatalyst composition of the present invention.

(I) Other additives:
In the visible light photocatalyst composition according to the present invention, if necessary,
Known dehydrating agents such as methyl orthoformate, methyl orthoacetate, tetraethoxysilane;
Polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polycarboxylic acid type polymer surfactant, polycarboxylate, polyphosphate, polyacrylate, polyamide ester salt, polyethylene glycol, etc. A dispersant can be blended.

Moreover, in order to improve the coating property (it is also called film forming property) of the composition which concerns on this invention, a leveling agent can be mix | blended. Examples of such leveling agents include BM-CHEMIE BM1000 (trade names, the same shall apply hereinafter), BM1100; Fuka Chemicals Fuka 772, Fuka 777; Kyoeisha Chemical Co., Ltd. Floren series; Sumitomo 3M Fluorine leveling agents such as Toho Chemical's Fluoronal TF series;
BYK series from Big Chemie; Sshmego series from Sshmegmann; Silicone series such as Fuka 30, Fuka 31, Fuka 34, Fuka 35, Fuka 36, Fuka 39, Fuka 83, Fuka 86, and Fuka 88 from Fuka Chemicals Leveling agents;
Carfinol manufactured by Nissin Chemical Industry Co., Ltd .; ether-based or ester-based leveling agents such as emulgen and homogenol manufactured by Kao Corporation.

By blending such a leveling agent, the finished appearance of the coating film is improved and a uniform thin film can be prepared.
In the present invention, the leveling agent is preferably used in an amount of 0.01 to 5% by weight, more preferably 0.02 to 3% by weight, based on the total composition.
The method of blending the leveling agent may be blended in the step of preparing the visible light photocatalyst composition according to the present invention, may be blended in the visible light photocatalyst composition in the step of forming a coating film, and You may mix | blend both in the preparation process of a visible light photocatalyst composition, and the formation process of a coating film.

<Method for producing visible light photocatalyst composition>
Specific examples of the method for producing the visible light photocatalyst composition according to the present invention include the following methods.

(1) When the oxide semiconductor (a) is a powder:
(E) Water and / or an organic solvent, (b) a titanium compound and / or (d) an organosiloxane oligomer are added to the oxide semiconductor (a) and dispersed, for example, by a disperser. ) A silane compound and, if necessary, (e) water and / or an organic solvent and / or (f) a catalyst are added to cause hydrolysis and condensation.

(2) When the oxide semiconductor (a) is a sol:
(B) a titanium compound and / or (d) an organosiloxane oligomer is added to the sol of the oxide semiconductor (a) and stirred, and then (c) a silane compound and, if necessary, (e ) Water and / or an organic solvent and / or (f) a catalyst are added to cause hydrolysis and condensation.

  In the production methods (1) and (2), the components (b) to (f) may be added all at once or sequentially. In particular, it is preferable to sequentially add a component having low compatibility with the oxide semiconductor (a). Here, “collective addition” means adding one kind of component at a time, and “sequential addition” means adding one kind of component over an arbitrary time. Furthermore, when components (b) to (f) are added all at once, components (b) to (f) may be added all at once, but are compatible with the oxide semiconductor (a). In consideration of the above, each component may be added independently.

By adding titanium compound (b) and / or organosiloxane oligomer (d) to oxide semiconductor (a), titanium compound (b) and / or organosiloxane oligomer (d) is adsorbed on oxide semiconductor (a). And / or reacts to ensure dispersion stability of the oxide semiconductor (a). In particular, when the cohesive force of the oxide semiconductor (a) is strong and difficult to disperse, it is preferable to use the titanium compound (b) and the organosiloxane oligomer (d) in combination.
Examples of the disperser used in the production method (1) include an ultrasonic disperser, a ball mill, a sand mill (bead mill), a homogenizer, an ultrasonic homogenizer, a nanomizer, a propeller mixer, and a high shear mixer.
In the production method (1), the secondary particle size (dispersed particle size) of the oxide semiconductor (a) is obtained by dispersing the oxide semiconductor (a) with a disperser in the presence of the titanium compound (b). Decreases. Furthermore, the oxide semiconductor (a) is adsorbed in the organosiloxane oligomer (d) by adsorbing with the structure represented by the formula (3) of the organosiloxane oligomer (d), thereby ensuring dispersion stability.
And by adding a silane compound (c) as needed, a silane compound plays the role of a binder, and even when there is much content of an oxide semiconductor (a), it can form into a film without choking.
The total solid concentration in the visible light photocatalyst composition according to the present invention is usually 1 to 50% by weight, preferably 3 to 40% by weight. When the total solid content exceeds the above upper limit, the storage stability may be lowered.

The visible light photocatalyst composition according to the present invention can usually be appropriately prepared according to the purpose of use. For example, the visible light photocatalyst composition can be used as a material for a coating film to be formed on a substrate or a material for repainting a deteriorated coating film. Can do.
<Coating film>
The coating film according to the present invention can be formed by forming the visible light photocatalyst composition on, for example, the following substrate.

(Base material)
Examples of the base material include metals such as iron, aluminum, and stainless steel;
Inorganic ceramic materials such as cement, concrete, lightweight concrete (ALC), flexible board, mortar, slate, gypsum, ceramics, bricks;
Plastic molded products such as phenol resin, epoxy resin, acrylic resin, polyester, polycarbonate, polyethylene, polypropylene, ABS resin (acrylonitrile-butadiene-styrene resin), thermoplastic norbornene resin;
Plastic films such as polyethylene, polypropylene, polyvinyl alcohol, polycarbonate, polyethylene terephthalate, polyurethane, polyimide, polyacryl, polyvinyl chloride, thermoplastic norbornene resin;
Examples thereof include inorganic materials such as silicon wafer, quartz glass, and glass, wood, and paper.

These substrates may be subjected to surface treatment in advance for the purpose of adjusting the foundation, improving adhesion, sealing the porous substrate, smoothing, patterning, and the like.
As surface treatment for metal base materials, polishing, degreasing, plating treatment, chromate treatment, flame treatment, coupling treatment, etc .;
Surface treatments for plastic base materials include blast treatment, chemical treatment, degreasing, flame treatment, oxidation treatment, steam treatment, corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, ion treatment, etc .;
As surface treatment for inorganic ceramic base materials, polishing, sealing, patterning, etc .;
Polishing, sealing, insect repellent treatment, etc.
As surface treatment for paper-based substrates, sealing, insect-proofing, etc .;
Examples of the surface treatment for the deteriorated coating film include keren.

Various primers may be used to ensure adhesion with the substrate.
(Coating film forming method)
Examples of the method of forming the coating film according to the present invention include a method of forming the visible light photocatalyst composition on a substrate and then drying the coating film.
As a method for forming the visible light photocatalyst composition on a substrate, for example, coating using a brush, roll coater, bar coater, flow coater, centrifugal coater, ultrasonic coater, (micro) gravure coater, etc .; dip coating; Spray coating; spraying; screen process; electrodeposition;

After forming a visible light photocatalyst composition on a substrate by these methods, the coating is stable by drying at room temperature, or by heating and drying at a temperature of about 30 to 200 ° C. for usually 1 to 60 minutes. A film can be formed.
When the visible light photocatalyst composition according to the present invention is formed, a coating film having a dry film thickness of about 0.05 to 20 μm in the case of one coating and a dry film thickness of about 0.1 to 40 μm in the case of two coatings. Can be formed.

The coating film which concerns on this invention contains the said oxide semiconductor (a), poly titanoxane, and polysiloxane. This polytitanoxane is assumed to be derived from the titanium compound (b). The polysiloxane is considered to be derived from the silane compound (c) and / or the organosiloxane oligomer (d).
It is desirable that the oxide semiconductor (a) is dispersed in the polysiloxane adjacent to the polytitanoxane and via the polytitanoxane.
The oxide semiconductor (a) is considered to have an action of reducing the dispersed particle size of the oxide semiconductor (a) and an action of improving dispersibility by being bonded to the polysiloxane via the polytitanoxane. Further, the polysiloxane has an effect of stabilizing the coating film.
The coating film concerning this invention is 1-50 weight part normally with respect to 100 weight part of solid content of the said oxide semiconductor (a), Preferably it is 2-45 weight part, More preferably, it is 3-40 weight. It is desirable to contain a part. When the content of polytitanoxane is less than the above lower limit, bond stability and dispersibility may be inferior, and when the upper limit is exceeded, the photocatalytic function with visible light may be impaired. Moreover, it is desirable that polysiloxane is contained in the coating film in an amount of usually 1 to 200 parts by weight, preferably 5 to 100 parts by weight, and more preferably 10 to 80 parts by weight. If the polysiloxane content is less than the above lower limit, sufficient dispersion stability may not be obtained. If the polysiloxane content exceeds the above upper limit, the formed coating film may be brittle, and choking may occur.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited at all by this Example. In the examples and comparative examples, parts and% are based on weight unless otherwise limited. Moreover, the photocatalyst composition was evaluated by the following method.
(1) Storage stability:
The photocatalyst composition was sealed in a polyethylene bottle at 40 ° C. for 3 months, and the presence or absence of gelation was determined visually. About what did not gelatinize, the viscosity measurement was performed with the BM type | mold viscosity meter by Tokyo Keiki Co., Ltd. The storage stability of the photocatalyst composition was evaluated according to the following criteria.

◎: Viscosity change rate before and after sealed storage is 20% or less ○: Viscosity change rate before and after sealed storage exceeds 20% ×: Gel formed after sealed storage (2) Transparency:
The photocatalyst composition was diluted with i-propyl alcohol to a solid content concentration of 5%, and ROD. NO. 3 was applied with a bar coater to a dry film thickness of 0.1 μm, and then dried at 150 ° C. for 30 minutes to prepare a photocatalyst-containing coating film. Haze of the coating film was measured using a haze tester (haze-gard plus illuminant CIE-C) manufactured by Gardner. The transparency of the coating film was evaluated according to the following criteria.
◎: Haze of 1 or less ○: Haze of more than 1 and 2 or less ×: Haze of more than 2

(3) Photocatalytic performance under visible light irradiation (visible light photocatalytic activity):
The photocatalyst composition was applied to a 100 cm ² aluminum plate by spray coating so as to have a dry film thickness of 10 μm, and dried at 150 ° C. for 30 minutes. When the obtained aluminum plate having a photocatalyst-containing coating film is placed in a glass bell jar and a 400 W xenon lamp (made by USHIO INC.) Is used and a glass filter that cuts off ultraviolet rays of less than 400 nm is used as visible light irradiation did. After exhausting the aldehyde in the system sufficiently, 1000 ppm of isopropanol was injected into a glass bell jar. After isopropanol reached the adsorption equilibrium, light irradiation was performed for 100 minutes, and acetone produced in the system was analyzed by gas chromatography (FID), and the photocatalytic performance under visible light irradiation was evaluated according to the following criteria.
◎: More than 100 ppm ○: More than 50 ppm and less than 100 ppm Δ: More than 1 ppm and less than 50 ppm x: Less than 1 ppm

<Example 1>
100 parts of oxygen defect type titanium dioxide having an absorbance at 400 nm of 0.06 as measured by diffuse reflection spectrum measurement as an oxide semiconductor (a), and a tetramer of tetra-n-butoxytitanium as a titanium compound (b) ( Nippon Soda Co., Ltd., trade name: B-10): 56 parts, methyltrimethoxysilane: 96 parts as the silane compound (c), and isopropyl alcohol: 700 parts as the organic solvent (e) are placed in a container. 3 mm zirconia beads: 600 parts were added, and the mixture was stirred and dispersed for 1 hour using a bead mill. Then, after removing the beads, 4 parts of di-i-propoxy / ethyl acetoacetate aluminum and 12 parts of water (e) were added as catalyst (f), and the mixture was heated and stirred at 60 ° C. for 4 hours, followed by isopropyl alcohol. The photocatalyst composition A was obtained by adjusting the solid concentration to about 10%. The composition A obtained had a storage stability of ◎, a transparency of ○, and a visible light photocatalytic activity of ◎.

<Example 2>
100 parts of oxygen-deficient type titanium dioxide having an absorbance at 400 nm of 0.10 measured by diffuse reflection spectrum measurement as an oxide semiconductor (a), and a tetramer of tetra-n-butoxytitanium as a titanium compound (b) (Japan) Soda Co., Ltd., trade name: B-10): 56 parts, methyltrimethoxysilane as a silane compound (c): 96 parts, organosiloxane oligomer (d) as MAC-2101 (manufactured by Nihon Unicar): 46 parts, organic As a solvent (e), 720 parts of isopropyl alcohol was placed in a container, 600 parts of zirconia beads having a particle diameter of 0.3 mm was added, and the mixture was stirred and dispersed for 1 hour using a bead mill. Then, after removing the beads, 4 parts of di-i-propoxy / ethyl acetoacetate aluminum and 6 parts of water (e) were added as catalyst (f), and the mixture was heated and stirred at 60 ° C. for 4 hours, followed by isopropyl alcohol. The photocatalyst composition B was obtained by adjusting the solid content concentration to about 10%. The resulting composition B had storage stability ◎, transparency 透明, and visible light photocatalytic activity ◎.

<Example 3>
Platinum-supported titanium dioxide having an absorbance at 400 nm of 0.08 measured by diffuse reflection spectrum measurement as an oxide semiconductor (a): 100 parts, tetramer of tetra-n-butoxytitanium as a titanium compound (b) ( Nippon Soda Co., Ltd., trade name: B-10): 60 parts, organosiloxane oligomer (d) as MAC-2101 (manufactured by Nihon Unicar): 56 parts, organic solvent (e) as isopropyl alcohol: 720 parts in a container Then, 600 parts of zirconia beads having a particle diameter of 0.3 mm were added, and the mixture was stirred and dispersed for 1 hour using a bead mill. Then, after removing the beads, 4 parts of di-i-propoxy / ethyl acetoacetate aluminum and 12 parts of water (e) were added as catalyst (f), and the mixture was heated and stirred at 60 ° C. for 4 hours, followed by isopropyl alcohol. The solid content concentration was adjusted to about 10% to obtain a photocatalyst composition C. The composition C thus obtained had storage stability ◎, transparency 透明, and visible light photocatalytic activity ◎.

<Example 4>
100 parts of platinum-supported titanium dioxide having an absorbance at 400 nm of 0.15 measured by diffuse reflection spectrum measurement as an oxide semiconductor (a): Tetrai-propoxytitanium decamer as titanium compound (b) (Japan) Soda Co., Ltd., trade name: A-10): 56 parts, silane compound (c) as methyltrimethoxysilane: 96 parts, organosiloxane oligomer (d) as MAC-2101 (manufactured by Nihon Unicar): 46 parts, organic As a solvent (e), 720 parts of isopropyl alcohol was placed in a container, 600 parts of zirconia beads having a particle diameter of 0.3 mm was added, and the mixture was stirred and dispersed for 1 hour using a bead mill. Then, after removing the beads, 4 parts of di-i-propoxy / ethyl acetoacetate aluminum and 12 parts of water (e) were added as catalyst (f), and the mixture was heated and stirred at 60 ° C. for 4 hours, followed by isopropyl alcohol. The solid content concentration was adjusted to about 10% to obtain a photocatalyst composition D. The resulting composition D had storage stability ◎, transparency 透明, and visible light photocatalytic activity ◎.

<Example 5>
100 parts of platinum-supported titanium dioxide having an absorbance at 400 nm of 0.15 measured by diffuse reflection spectrum measurement as an oxide semiconductor (a): tetramer of tetra-n-butoxytitanium as a titanium compound (b) (Japan) Soda Co., Ltd., trade name: B-7): 56 parts, silane compound (c) as methyltrimethoxysilane: 96 parts, organosiloxane oligomer (d) as MAC-2101 (manufactured by Nihon Unicar): 46 parts, organic As a solvent (e), 720 parts of isopropyl alcohol was placed in a container, 600 parts of zirconia beads having a particle diameter of 0.3 mm was added, and the mixture was stirred and dispersed for 1 hour using a bead mill. Then, after removing the beads, 4 parts of di-i-propoxy / ethyl acetoacetate aluminum and 12 parts of water (e) were added as catalyst (f), and the mixture was heated and stirred at 60 ° C. for 4 hours, followed by isopropyl alcohol. The solid content concentration was adjusted to about 10% to obtain a photocatalyst composition D. The resulting composition D had storage stability ◎, transparency 透明, and visible light photocatalytic activity ◎.

<Comparative example 1>
Prepared in the same manner as in Example 1 except that anatase-type titanium oxide (trade name: ST-01, manufactured by Ishihara Sangyo Co., Ltd.) having an absorbance at 400 nm of less than 0.02 measured by diffuse reflection spectrum measurement was used as the component (a). did. The storage stability of the obtained composition was ◎, the transparency was ◎, and the visible light photocatalytic activity was x.

<Comparative example 2>
It was prepared in the same manner as in Example 4 except that the titanium compound (b) and the organosiloxane oligomer (d) were not used. The storage stability of the obtained composition was x (sediment separation in 10 minutes after standing), and the transparency was x.

<Comparative Example 3>
Prepared in the same manner as in Example 5 except that the titanium compound (b) was not used. The storage stability of the obtained composition was x (sediment separation in 10 minutes after standing), and the transparency was x.

Claims (8)

(A) an oxide semiconductor having visible light photocatalytic activity,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(In the formula, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more exist, they may be the same or different, and R ² represents an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ¹ and R ² are the same Or m may be an integer of 0 to 3)
And at least one titanium compound selected from the group consisting of a titanium acylate represented by the above formula (1) and a derivative thereof,
And (c) the following general formula (2)
R ³ _n Si (OR ⁴ ) _4-n (2)
(In the formula, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when a plurality of R ³ are present, they may be the same or different, and R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when there are a plurality of them, they may be the same or different, and R ³ and R ⁴ may be the same or different; n is an integer of 0 to 3)
At least one silane compound selected from the group consisting of organosilanes and derivatives thereof,
And a photocatalytic activity under irradiation with visible light of 400 nm or more. (A) an oxide semiconductor having visible light photocatalytic activity,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(In the formula, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more exist, they may be the same or different, and R ² represents an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ¹ and R ² are the same Or m may be an integer of 0 to 3)
And at least one titanium compound selected from the group consisting of a titanium alcoholate represented by the formula (1) and a titanium acylate represented by the formula (1) and a derivative thereof, and (d) a Si-O bond. Having a weight average molecular weight of 300 to 100,000 and the following formula (3)
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(In the formula, R ⁵ and R ⁶ represent an alkyl group having 1 to 5 carbon atoms, which may be the same or different, and R ⁷ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. , P and q are numbers such that the value of p + q is 2 to 50)
An organosiloxane oligomer containing a structure represented by:
And a photocatalytic activity under irradiation with visible light of 400 nm or more. (A) an oxide semiconductor having visible light photocatalytic activity,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(In the formula, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more exist, they may be the same or different, and R ² represents an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ¹ and R ² are the same Or m may be an integer of 0 to 3)
And at least one titanium compound selected from the group consisting of a titanium acylate represented by the above formula (1) and a derivative thereof,
(C) The following general formula (2)
R ³ _n Si (OR ⁴ ) _4-n (2)
(In the formula, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when a plurality of R ³ are present, they may be the same or different, and R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when there are a plurality of them, they may be the same or different, and R ³ and R ⁴ may be the same or different; n is an integer of 0 to 3)
And at least one silane compound selected from the group consisting of organosilanes and derivatives thereof, and (d) having a Si—O bond, a weight average molecular weight of 300 to 100,000, and the following formula: (3)
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(In the formula, R ⁵ and R ⁶ represent an alkyl group having 1 to 5 carbon atoms, which may be the same or different, and R ⁷ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. , P and q are numbers such that the value of p + q is 2 to 50)
An organosiloxane oligomer containing a structure represented by:
And having a photocatalytic activity under irradiation with visible light of 400 nm or more. (A) The visible light photocatalytic composition according to any one of claims 1 to 3, wherein the oxide semiconductor having visible light photocatalytic activity has an absorbance at 400 nm of 0.05 or more as measured by diffuse reflection spectrum measurement. (A) An oxide semiconductor having visible light photocatalytic activity is brookite-type titanium oxide, ion-implanted type titanium oxide, plasma-treated titanium oxide, oxygen-deficient titanium oxide, nitrogen-doped titanium oxide, sulfur-doped titanium oxide and platinum The visible light photocatalyst composition according to claim 1, which is at least one selected from the group consisting of supported titanium oxide. Furthermore, (f) a catalyst is contained, The visible light photocatalyst composition in any one of Claims 1-5 characterized by the above-mentioned. The visible light photocatalyst composition according to any one of claims 1 to 6, wherein the haze is 2 or less when a dry coating film having a thickness of 0.1 µm is formed. The visible light photocatalyst containing coating film obtained from the visible light photocatalyst composition in any one of Claims 1-7.