JP2004099879A - Composition for coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silane-based coating composition which contains metal fine particles and / or metal oxide fine particles, has good dispersibility even at a high concentration of these fine particles, and can provide a coating film having high transparency.
SOLUTION: (a) metal fine particles and / or metal oxide fine particles, (b) a titanium compound having a specific structure and / or (d) an organosiloxane oligomer having a specific structure, and (c) a silane having a specific structure. A coating composition containing a compound.
[Selection diagram] None

Description

The present invention relates to a coating film having good fine particle dispersibility and high transparency, and a silane-based coating composition for obtaining the coating film.

A coating material containing metal fine particles and / or metal oxide fine particles can be widely used for optical materials, catalyst materials, electronic materials, sensor materials, and the like. In addition, silane-based binders are preferably used as binders for metal fine particles and metal oxide fine particles particularly under ultraviolet light and high temperature because of their excellent durability compared to organic binders. As a method for producing a silane-based coating material containing the metal oxide fine particles and the like,
(1) A method in which metal fine particles and / or metal oxide fine particles are finely divided and dispersed in a solvent having good compatibility to form a sol state, and then mixed with a silane-based binder (Patent Document 1).
(2) After mixing the hydrolyzable silane as a raw material of the silane-based binder with the metal fine particles and / or the metal oxide fine particles, the hydrolyzable silane is increased in molecular weight in the presence of the metal fine particles and / or the metal oxide. Method (Patent Document 2)
And the like.

However, in these methods, especially when the content of the metal fine particles and / or metal oxide fine particles is increased, the dispersion stability is deteriorated, and the particles often aggregate to lower the transparency of the coating film. Cannot be applied to required applications. In particular, when the content of the metal fine particles and / or the metal oxide fine particles exceeds 25%, the decrease in transparency becomes remarkable.
JP-A-6-25600 JP 2000-246114 A

The present invention is intended to solve the problems associated with the prior art as described above, and contains metal fine particles and / or metal oxide fine particles, has good dispersibility of these fine particles, and has high transparency. An object of the present invention is to provide a silane-based coating composition from which a coating film can be obtained, and a coating film obtained from the coating composition.

The present inventors have intensively studied to solve the above problems, and in a coating composition containing a hydrolyzable silane and a titanium compound having a specific structure and / or an organosiloxane oligomer having a specific structure, The high content metal fine particles and / or metal oxide fine particles are well dispersed, and the dried coating film having a thickness of 0.2 μm obtained from this coating composition has high transparency with a total light transmittance of 80% or more. And found that the invention was completed.

That is, the first coating composition according to the present invention,
(A) metal fine particles and / or metal oxide fine particles,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(Wherein, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ² is an alkyl group having 1 to 6 carbon atoms) 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 a plurality of groups are present, they may be the same or different; m is an integer of 0 to 3 is there)
And at least one titanium compound selected from the group consisting of titanium alcoholate and its derivative represented by the above formula (1), and (c) the following formula (2) )
R ³ _n Si (OR ⁴ ) _4-n (2)
(Wherein, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when two or more are present, they may be the same or different; n is an integer of 0 to 3)
Wherein at least one silane compound selected from the group consisting of organosilanes and derivatives thereof is contained.

Further, the second coating composition according to the present invention,
(A) metal fine particles and / or metal oxide fine particles,
(C) Formula (2) below
R ³ _n Si (OR ⁴ ) _4-n (2)
(Wherein, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when two or more are present, they 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, having a weight average molecular weight of 300 to 100,000, and Equation (3)
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(Wherein, R ⁵ and R ⁶ represent an alkyl group having 1 to 5 carbon atoms, and when two or more are present, they may be the same or different; R ⁷ is a hydrogen atom or a carbon atom having 1 to 5 carbon atoms. Represents five alkyl groups, and p and q are numbers such that the value of p + q is 2 to 50)
Characterized by containing an organosiloxane oligomer having a structure represented by the following formula:

Further, three coating compositions according to the present invention,
(A) metal fine particles and / or metal oxide fine particles,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(Wherein, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ² is an alkyl group having 1 to 6 carbon atoms) 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 a plurality of groups are present, they may be the same or different; m is an integer of 0 to 3 is there)
A titanium alcoholate and a derivative thereof, and at least one titanium compound selected from the group consisting of a titanium acylate and a derivative thereof represented by the above formula (1),
(C) Formula (2) below
R ³ _n Si (OR ⁴ ) _4-n (2)
(Wherein, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when two or more are present, they 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, having a weight average molecular weight of 300 to 100,000, and Equation (3)
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(Wherein, R ⁵ and R ⁶ represent an alkyl group having 1 to 5 carbon atoms, and when two or more are present, they may be the same or different; R ⁷ is a hydrogen atom or a carbon atom having 1 to 5 carbon atoms. Represents five alkyl groups, and p and q are numbers such that the value of p + q is 2 to 50)
A coating composition comprising an organosiloxane oligomer having a structure represented by the formula:

第一 It is preferable that the first to third coating compositions according to the present invention further contain (f) a catalyst.

コ ー テ ィ ン グ The coating film according to the present invention can be obtained from the coating composition.

According to the present invention, there is provided a coating composition containing fine metal particles and / or fine metal oxide particles, which has good dispersibility and high transparency even when the fine metal particles and / or fine metal oxide particles have a high content. A coating composition capable of obtaining a high coating film can be obtained.

First, each component of the coating composition according to the present invention will be described in detail.

(A) Metal fine particles and metal oxide fine particles:
The metal fine particles and metal oxide fine particles (hereinafter, collectively referred to as “fine particles (a)”) used in the present invention may be a powder, water-based sol or colloid dispersed in water, or alcohol or the like. It may be in the form of an organic solvent sol or colloid dispersed in a polar solvent or a non-polar solvent such as toluene. When the fine particles (a) are an organic solvent-based sol or colloid, the fine particles (a) may be further diluted with water or an organic solvent according to the dispersibility thereof, and the fine particles (a) may be diluted to improve the dispersibility. The surface may be treated and used. The form of the fine particles (a) is appropriately determined according to the desired properties of the coating film. When the fine particles (a) are in the form of a sol or a colloid, the solid concentration is preferably 40% by weight or less.

The primary particle diameter of the fine particles (a) is desirably 200 nm or less, preferably 100 nm or less. When the primary particle diameter exceeds the above range, the transparency of the coating film is reduced, and the total light transmittance when a dried coating film having a thickness of 0.2 μm is formed may be less than 80%.

Specific examples of the fine particles (a) used in the present invention include the following compounds. For example, 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, SiO 2, Al 2} 0 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, BaTi
_{O 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 _1.73 , Mg ₂ Si, β-B, BaC, BP, TiB ₂ , ZrB ₂ , HfB ₂ , Ru ₂ Si ₃ , TiO ₂ (rutile type, anatase 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, and a Sr ferrite. These compounds can be used alone or as a mixture of two or more kinds, and a compound obtained by combining these compounds can also be used. Further, a compound obtained by supporting another metal such as platinum on these compounds or a compound modified with another element can be used.

Among such compounds, anatase type TiO ₂ is suitably used for forming a photocatalytic coating film having an organic substance decomposing function or an antifouling function by superhydrophilization.

The fine particles (a) are present in the coating composition in an amount of from 1% to 90% by weight, preferably from 15 to 85% by weight, more preferably from 25 to 80% by weight, based on the total solids of the composition. Is desirably contained. If the total amount of the fine particles (a) is less than the lower limit relative to the total solid content of the coating composition, the characteristics of the fine particles (a) may not be exhibited, and if the total amount exceeds the upper limit, a coating film may be formed. In this case, chalking or the like may occur, and the film-forming property may be poor.

(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)
(Wherein, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ² is an alkyl group having 1 to 6 carbon atoms) 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 a plurality of groups are present, they may be the same or different; m is an integer of 0 to 3 is there)
And at least one titanium compound selected from the group consisting of titanium alcoholate and its derivative, and titanium acylate and its derivative represented by the above formula (1).

As the derivatives of titanium alcoholate, hydrolysates of the titanium alcoholate, condensates of the titanium alcoholate, chelate compounds of the titanium alcoholate, hydrolysates of the chelate compound of the titanium alcoholate, and the titanium alcoholate And a condensate of a chelate compound of the formula (1).

Further, as the derivative of titanium acylate, 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 A condensate of a chelate compound of an acylate is exemplified.

These titanium compounds may be used alone or in a mixture of two or more.

In the above formula (1), R ¹ is an organic group having 1 to 8 carbon atoms.
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, n-heptyl group, n-octyl group An alkyl group such as a 2-ethylhexyl group;
Acyl groups such as acetyl, propionyl, butyryl, valeryl, benzoyl, trioil and caproyl;
Examples 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.

Further, R ^{1 includes} a substituted derivative of the above organic group. 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 Ureido group, ammonium base and the like. However, the number of carbon atoms of R ¹ composed of these substituted derivatives is preferably 8 or less including 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, a methyl group, an 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, n-octyl group, 2-ethylhexyl group and the like. No.

Further, as R ² having 1 to 6 carbon atoms, an acetyl group, a propionyl group,
Examples thereof include a butyryl group, a valeryl group, a benzoyl group, a trioil group, and a caproyl group.

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, hydroxycarboxylate, keto alcohol and amino alcohol. It can be obtained by reacting with at least one compound (hereinafter, also referred to as a chelating agent). Further, the chelate compound of titanium acylate can be obtained by reacting the titanium acylate with the chelating agent. Among these chelating agents, β-diketones or β-ketoesters are preferably used. More specifically, acetylacetone, methyl acetoacetate, ethyl acetoacetate, n-propyl acetoacetate, i-propyl acetoacetate, n-butyl acetoacetate, sec-butyl acetoacetate, t-butyl acetoacetate , 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane-dione, 5-methyl-hexane-dione and the like. Used.

Specific examples of titanium alcoholate and the chelate compound of titanium alcoholate include tetra-i-propoxytitanium, tetra-n-butoxytitanium, tetra-t-butoxytitanium, and di-i-propoxybis (ethylacetoacetate). Titanium, di-i-propoxy bis (acetyl acetate) titanium, di-i-propoxy bis (lactate) titanium, di-i-propoxy bis (acetylacetonate) titanium, di-n-butoxy bis (tri Ethanolamine) titanium, di-n-butoxybis (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 (acetylacetonato ) Titanium is preferred.

Specific examples of titanium acylate and a chelate compound of titanium acylate include dihydroxytitanium dibutyrate, di-i-propoxytitanium diacetate, bis (acetylacetonato) titanium diacetate, and bis (acetylacetate). Nart) titanium dipropionate, di-i-propoxy titanium dipropionate, di-i-propoxy titanium dimallonate, di-i-propoxy titanium dibenzoylate, di-n-butoxy zirconium diacetate And di-i-propylaluminum monomalonate. Of these, dihydroxy titanium dibutyrate and di-i-propoxy titanium diacetate are preferred.

Titanium alcoholate hydrolyzate, titanium alcoholate chelate compound hydrolyzate, titanium acylate hydrolyzate, or titanium acylate chelate compound hydrolyzate is included 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 compound condensate, titanium acylate condensate, and titanium acylate chelate compound condensate are titanium alcoholate, titanium alcoholate chelate compound, titanium acylate, respectively. A Ti—OH group in a hydrolyzate produced by hydrolysis of a chelate compound of a rate and a titanium acylate forms 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 may be obtained by condensing a part of the Ti-OH groups, or by most (including all) Ti-OH groups. And also a mixture of condensates in which a Ti-OR group and a Ti-OH group are mixed.

In the present invention, the titanium compound (b) is more preferably used in order to control the reactivity and suppress gelation, and the condensation degree of the condensate is from dimer to decamer. Is particularly preferred. This condensate is titanium alcoholate, a chelate compound of titanium alcoholate, a titanium acylate, and a mixture of one or more titanium compounds selected from the group consisting of chelate compounds of titanium acylate, Hydrolyzed and condensed products may be used in advance, or commercially available condensates may be used. In addition, the condensate of titanium alcoholate or titanium acylate may be used as it is, or a product obtained by hydrolyzing a part or all of the OR ² group contained in the condensate, or the above-described chelate of the condensate. It may be used as a condensate of a chelate compound of titanium alcoholate or titanium acylate obtained by reacting with an agent.

Examples of commercially available condensates of titanium alcoholate (from dimer to decamer) include A-10, B-2, B-4, B-7, and B-10 manufactured by Nippon Soda Co., Ltd. Can be

チ タ ン Such a titanium compound (b) may be used alone or in combination of two or more.

The amount of the titanium compound (b) used in the present invention is 1 to 50 parts by weight, preferably 2 to 40 parts by weight, in terms of a completely hydrolyzed condensate, based on 100 parts by weight of the solid content of the fine particles (a). Preferably 5 to 30 parts by weight is preferred. The term “completely hydrolyzed condensate” as used herein means that the OR ² group in the formula (1) is hydrolyzed 100% to form a Ti—OH group, and the Ti—OH group is completely condensed to form a Ti—O—Ti structure. Is formed.

チ タ ン It is considered that these titanium compounds (b) are adsorbed and bonded to the surface of the fine particles (a) and have an effect of reducing the dispersed particle diameter of the fine particles (a) and an effect of increasing the dispersibility.

(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)
(Wherein, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different, and R ⁴ may have 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when two or more are present, they may be the same or different; 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 organosilane (hereinafter, referred to as “organosilane (2)”) and a derivative thereof.

Examples of the organosilane (2) derivative include a hydrolyzate of the organosilane (2) and a condensate of the organosilane (2).

The silane compound (c) used in the present invention is at least one silane compound selected from the group consisting of an organosilane (2), a hydrolyzate of the organosilane (2), and a condensate of the organosilane (2). Thus, among these three silane compounds, only one silane compound may be used, two arbitrary silane compounds may be mixed and used, or all three silane compounds may be mixed and used. May be used.

In the above formula (2), R ³ is a monovalent organic group having 1 to 8 carbon atoms, and specifically, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group An alkyl group 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, propionyl, butyryl, valeryl, benzoyl, trioil and caproyl;
Examples 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.

Further, 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 Ureido group, ammonium base and the like. However, the number of carbon atoms of R ³ composed of these substituted derivatives is preferably 8 or less including 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 having an alkyl group having 1 to 5 carbon atoms, for example, a methyl group, an ethyl group, n
-Propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group and the like. Examples of the acyl group having 1 to 6 carbon atoms include an acetyl group. , Propionyl, butyryl, valeryl, caproyl and the like.

When a plurality of R ⁴ are present in the formula (2), they may be the same or different.

Specific examples of the 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) attacryloxypropyltriethoxysilane, 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;
Methyltriacetyloxysilane, dimethyldiacetyloxysilane and the like can be mentioned.

Of these, trialkoxysilanes and dialkoxysilanes are preferred, and more preferably, as trialkoxysilanes, methyltrimethoxysilane and methyltriethoxysilane are desirable, and as dialkoxysilanes, dimethyldimethoxysilane, dimethyldimethoxysilane Ethoxysilane is preferred.

は As the organosilane (2) used in the present invention, the above-mentioned 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 the dialkoxysilane and the trialkoxysilane in combination, the obtained coating film is softened and the alkali resistance can be improved.

In the present invention, the organosilane (2) may be used as it is as the silane compound (c), but a hydrolyzate and / or condensate of the organosilane (2) can be used.

The hydrolyzate of the organosilane (2) only needs to be hydrolyzed at least one of 2 to 4 OR ⁴ groups contained in the organosilane (2), for example, one OR ⁴ group May be hydrolyzed, or two or more OR ⁴ groups may be hydrolyzed, or a mixture thereof.

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

Such a hydrolyzate and / or condensate of organosilane (2) can be produced by previously hydrolyzing and condensing organosilane (2). Further, as described later, when preparing the coating composition, the organosilane (2) and water are hydrolyzed and condensed to prepare a hydrolyzate and / or condensate of the organosilane (2). You can also. This water may be added independently, or fine particles (a) or water (e) described later or water contained in an organic solvent may be used. The amount of the water is usually 0.5 to 3 mol, preferably 0.7 to 2 mol, per 1 mol of the organosilane (2).

Such an organosilane (2) condensate has a polystyrene-equivalent weight average molecular weight (hereinafter, referred to as “Mw”) of preferably 300 to 100,000, more preferably 400 to 70,000, and particularly preferably. 500-50,000 condensates are used.

は 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, silicon resin manufactured by Dow Corning Toray, silicon resin manufactured by Toshiba Silicone Co., Ltd., Shin-Etsu Chemical Co., Ltd. And a hydroxyl group-containing polydimethylsiloxane manufactured by Dow Corning Asia Co., Ltd., and a silicon oligomer manufactured by Nippon Yunika Co., Ltd. These commercially available silane compounds may be used as they are or may be used after condensation.

は Such a silane compound (c) may be used alone or as a mixture of two or more.

In the present invention, the silane compound (c) is at least 2% by weight, preferably at least 5% by weight, in terms of a complete hydrolyzed condensate, based on the solid content of the coating composition excluding the fine particles (a). , More preferably at least 10% by weight. Here, the completely hydrolyzed condensate is a product in which the OR ⁴ group in the formula (2) is hydrolyzed 100% to form a Si—OH group, and further 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 chalking or the like may occur.

(D) Organosiloxane oligomer:
The organosiloxane oligomer (d) used in the present invention has a Si—O bond, a weight average molecular weight of 300 to 100,000, and has the following formula (3) on the side chain and / or terminal.
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(Wherein, 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, p and q each represent Independently, it is a number such that the value of p + q is 2 to 50)
It contains the structure represented by

官能 As the functional group represented by the above formula (3), a polyoxyalkylene group such as a polyoxyethylene group, a polyoxypropylene group, and a poly (oxyethylene / oxypropylene) group can be given. When the organosiloxane oligomer (d) contains such a functional group, the polyoxyalkylene group portion in the functional group is easily adsorbed on the fine particles (a), and the dispersion stability of the fine particles (a) is improved.

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.

と し て Examples of the halogen atom include fluorine and chlorine.

Examples of the organic group having 1 to 15 carbon atoms include an alkyl group, an acyl group, an alkoxyl group, an alkoxysilyl group, a vinyl group, an allyl group, an acetoxyl group, an acetoxysilyl group, a cycloalkyl group, a phenyl group, a glycidyl group, and (meth) acryl. Examples include an oxy group, a ureido group, an amide group, a fluoroacetamide group, an isocyanate group, and the like.

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 and the like. Can be

ア シ ル Examples of the acyl group having 1 to 15 carbon atoms include an acetyl group, a propionyl group, a butyryl group, a valeryl group, a benzoyl group, and a toluoyl group.

ア ル コ キ シ 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.

ア ル コ キ シ 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.

基 These groups may be partially hydrolyzed / condensed or substituted derivatives. Examples of the substituent of the substituted derivative 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, Examples include an ammonium base and a ketoester group.

Among these, an organosiloxane oligomer (d) having a structure in which a silicon atom of a silyl group is bonded to a hydrolyzable group and / or a hydroxyl group is preferably used. For example, a condensate of chlorosilane or a condensate of alkoxysilane is used. Can be Such an organosiloxane oligomer (d) is fixed by co-condensing with the titanium compound (b) and the silane compound (c) when the coating composition according to the present invention is cured, so that a stable coating film is obtained. Can be obtained. When the organosiloxane oligomer (d) has a glycidyl group, the adhesion to the substrate and the undercoat layer is improved. In particular, when an organosiloxane oligomer (d) having a structure in which a silicon atom of a silyl group is bonded to a hydrolyzable group and / or a hydroxyl group and a glycidyl group in one molecule is used, the resulting coating film becomes tough, Adhesion with the substrate is further improved.

The weight average molecular weight (hereinafter, also referred to as “Mw”) of the organosiloxane oligomer (d) in terms of polystyrene is 300 to 100,000, preferably 600 to 50,000, and particularly preferably 1,000 to 20,000. When the weight average molecular weight is less than the above lower limit, the flexibility of the obtained coating film is insufficient, and when it exceeds the above upper limit, the storage stability of the obtained coating composition is reduced.

に お い て In the present invention, the organosiloxane oligomer (d) may be used alone or as a mixture of two or more. As an organosiloxane oligomer (d) in which two or more kinds are mixed, a mixture of an organosiloxane oligomer having an Mw of 400 to 2,800 and an organosiloxane oligomer having an Mw of 3,000 to 50,000, or having a different functional group 2 Mixtures of different organosiloxane oligomers.

In the present invention, commercially available organosiloxane oligomers can be used as the organosiloxane oligomer (d). For example, modified silicone oil manufactured by Toray Dow Corning Co., and modified silicone oil manufactured by Toshiba Silicone Co., Ltd. And modified silicone oligomers manufactured by Shin-Etsu Chemical Co., Ltd., and modified silicone oligomers manufactured by Nippon Yunika. These organosiloxane oligomers may be used as they are, or may be used after condensation.

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 60 parts by weight, based on 100 parts by weight of the solid content of the fine particles (a). Part is desirable. If the amount of the organosiloxane oligomer (d) is less than the above lower limit, the dispersion stability may be poor. If the amount exceeds the above upper limit, the formed coating film may be brittle and chalking may occur.

(E) water and / or organic solvent:
The coating composition according to the present invention 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,
Examples of aromatic hydrocarbons include benzene, toluene, xylene, and the like,
Examples of ethers include tetrahydrofuran, dioxane, and the like,
As ketones, acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone and the like,
Examples of the esters include ethyl acetate, propyl acetate, butyl acetate, propylene carbonate, methyl lactate, ethyl lactate, normal propyl lactate, isopropyl lactate, methyl 3-ethoxypropionate, and ethyl 3-ethoxypropionate.

These organic solvents may be used alone or as a mixture of two or more.

(F) catalyst:
The coating composition according to the present invention preferably contains a catalyst (f). 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 collectively referred to as an organometallic compound and / or a partial hydrolyzate thereof) And "organometallic compounds".

酸性 Examples of the acidic compound include acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, alkyltitanic acid, p-toluenesulfonic acid, and phthalic acid. Of 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 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-aminopropyltrimethoxy. 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, quaternary ammonium salts. Further, various modified amines used as a curing agent for the epoxy resin can also be used. Of these, 3-aminopropyl-trimethoxysilane, 3-aminopropyl-triethoxysilane, and 3- (2-aminoethyl) -aminopropyl-trimethoxysilane are preferred.

Examples of the organometallic compounds include the following formula (4)
M (OR ⁸ ) _r (R ⁹ COCHCOR ¹⁰ ) _s (4)
(Wherein 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 an ethyl group, an n-propyl group, an i- Represents a monovalent hydrocarbon group having 1 to 6 carbon atoms such as a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, a cyclohexyl group, and a phenyl group. , R ¹⁰ is the monovalent hydrocarbon group having 1 to 6 carbon atoms or a methoxy group, an ethoxy group, n- propoxy group, i- propoxy, n- butoxy group, sec- butoxy group, t- Represents an alkoxyl group having 1 to 16 carbon atoms such as a butoxy group, a lauryloxy group, a stearyloxy group, and r and s are each independently an integer of 0 to 4, and (r + s) = (valence of M )connection of Satisfy)
(Hereinafter referred to as "organometallic compound (4)"),
An organometallic compound of tetravalent tin 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.

チ タ ン Further, as the organometallic compounds, the above-mentioned titanium compound (b) can be used.

As the organometallic compound (4), for example, tetra-n-butoxyzirconium, tri-n-butoxyethylacetoacetate zirconium, di-n-butoxybis (ethylacetoacetate) zirconium, n-butoxytris (ethylacetate) Acetate) zirconium, tetrakis (n-propylacetoacetate) zirconium, tetrakis (
Organic zirconium compounds such as acetylacetoacetate) zirconium and tetrakis (ethylacetoacetate) zirconium;
Organic titanium compounds such as tetra-i-propoxytitanium, di-i-propoxybis (ethylacetoacetate) titanium, di-i-propoxybis (acetylacetate) titanium, di-i-propoxybis (acetylacetone) titanium ;
Aluminum tri-i-propoxy, aluminum di-i-propoxy ethyl acetoacetate, aluminum di-i-propoxy acetylacetonate, aluminum i-propoxy bis (ethyl acetoacetate), i-propoxy bis (acetyl acetonate) A) aluminum, tris (ethylacetoacetate) aluminum, tris (acetylacetonate) aluminum, and organic aluminum compounds such as monoacetylacetonatobis (ethylacetoacetate) aluminum.

Among these organometallic compounds (4) and partial hydrolysates thereof, tri-n-butoxyethylacetoacetate zirconium, di-i-propoxybis (acetylacetonato) titanium, di-i-propoxyethylacetate Acetate aluminum, tris (ethylacetoacetate) aluminum, or a partial hydrolyzate thereof is preferably used.

と し て As an organotin compound, for example,

Carboxylic acid type organotin compounds such as;

Mercaptide-type organotin compounds such as;

Sulfide-type organotin compounds such as;

Chloride-type organotin compounds such as;
(C ₄ H ₉ ) ₂ SnO,
(C ₈ H ₁₇ ) ₂ SnO
Organic tin oxides such as;
Reaction products of these organic tin oxides and ester compounds such as silicate, dimethyl maleate, diethyl maleate, and dioctyl phthalate are exemplified.

触媒 Such a catalyst (f) may be used alone or in combination of two or more, or may be used in combination with a zinc compound or another reaction retarder.

The catalyst (f) may be blended in the step of preparing the coating composition according to the present invention, or may be blended in the coating composition in the step of forming a coating film. It may be blended in both the step of preparing the composition and the step of forming the coating film.

The amount of the catalyst (f) used in the present invention is usually 10 mol or less, preferably 0.001 to 7 mol, more preferably 0.1 mol, per 1 mol of the OR ⁴ group contained in the silane compound (c). 001 to 5 mol is desirable. If the amount of the catalyst (f) exceeds the above upper limit, the storage stability of the coating composition may decrease, or cracks may occur in the coating film.

(4) The catalyst (f) promotes a 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 generated by the polycondensation reaction of the silane compound (c) or the organosiloxane oligomer (d) increases, and the curing rate of the obtained coating film is reduced. As a result, a coating film having excellent strength and durability can be obtained, and the thickness of the coating film can be increased.

(G) Stability improver:
The coating composition according to the present invention may contain a stability improver (g) as necessary. The stability improver (g) used in the present invention has the following formula (5)
R ¹¹ COCH ₂ COR ¹² (5)
(Wherein, R ¹¹ represents an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, a cyclohexyl group, a phenyl R ¹² represents a monovalent hydrocarbon group having 1 to 6 carbon atoms such as a group,
Carbon number such as a divalent hydrocarbon group or a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, a sec-butoxy group, a t-butoxy group, a lauryloxy group, a stearyloxy group Represents 1 to 16 alkoxyl groups)
And 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, n-propyl acetoacetate, i-propyl acetoacetate, n-butyl acetoacetate, acetoacetate-sec- Butyl, t-butyl acetoacetate, 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, Onin, such as salicylic aldehyde, and the like. Of these, acetylacetone and ethyl acetoacetate are preferred.

The stability improver (g) is particularly preferably used when an organometallic compound is used as the titanium compound (b) or the catalyst (f). Further, the stability improver (g) may be used alone or as a mixture of two or more.

By using the stability improver (g), the stability improver (g) coordinates to the metal atom of the organometallic compound, and this coordination is caused by the silane compound (c) or the organosiloxane oligomer (d). It is considered that the accelerating action of the organometallic compound on the co-condensation reaction can be appropriately adjusted to further improve the storage stability of the obtained coating composition.

量 The amount of the stability improver (g) used in the present invention is usually 2 mol or more, preferably 3 to 20 mol, per 1 mol of the organometallic compound of the above-mentioned organometallic compounds. When the amount of the stability improver (g) is less than the above lower limit, the effect of improving the storage stability of the obtained composition may be insufficient in a coating composition having a high solid content concentration.

(H) filler:
In the coating composition according to the present invention, a filler can be added and dispersed as necessary for coloring and thickening the obtained coating film.

As the filler used in the present invention, water-insoluble organic pigments and inorganic pigments; ceramics, metals or alloys other than particulate, fibrous or scaly 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 blue, navy blue, pigment green, rock ultramarine, cobalt blue, cerulean blue, copper borate, molybdenum blue , Copper sulfide, cobalt purple, mars purple, man Purple, pigment violet, lead suboxide, calcium lead oxide, zinc yellow, lead sulfide, chrome yellow, loess, cadmium yellow, strontium yellow, titanium yellow, litharge, pigment yellow, cuprous oxide, cadmium red, selenium red, chrome bar Million, Bengala, zinc white, antimony white, basic lead sulfate, titanium white, lithopone, lead silicate, zircon oxide, tungsten white, lead, zinc white, vantisone 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 combination of two or more.

The amount of the filler is preferably 300 parts by weight or less based on 100 parts by weight of the total solid content of the coating composition.

(I) Other additives:
The coating composition according to the present invention, if necessary,
Known dehydrating agents such as methyl orthoformate, methyl orthoacetate, and 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;
Celluloses such as methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose and hydroxypropylmethylcellulose;
Thickeners such as castor oil derivatives and ferrosilicates;
Inorganic blowing agents such as ammonium carbonate, ammonium bicarbonate, ammonium nitrite, sodium borohydride, calcium azide;
Organic blowing agents such as azo compounds such as azobisisobutyronitrile, hydrazine compounds such as diphenylsulfone-3,3'-disulfohydrazine, semicarbazide compounds, triazole compounds and N-nitroso compounds;
Surfactant;
A dye or the like can be blended.

In order to further improve the coating property (also referred to as film-forming property) of the composition according to the present invention, a leveling agent can be blended. Examples of such a leveling agent include BM1000 (trade name, hereinafter the same) and BM1100 manufactured by BM-CHEMIE; Efka 772 and Efka 777 manufactured by Efka Chemicals; Floren series manufactured by Kyoeisha Chemical Co., Ltd .; Fluorine leveling agent such as FC series of 3M Co., Ltd .;
BYK series of Big Chemie; Sshmego series of Shmegmann; Leveling agent;
Carfinol manufactured by Nissin Chemical Industry Co., Ltd .; ether-based or ester-based leveling agents such as Emulgen and Homogenol manufactured by Kao Corporation.

配合 By blending such a leveling agent, the finished appearance of the coating film can be improved and a uniform thin film can be prepared.

に お い て In the present invention, the leveling agent is used in an amount of preferably 0.01 to 5% by weight, more preferably 0.02 to 3% by weight, based on the whole composition.

The method of blending the leveling agent may be blended in the step of preparing the coating composition according to the present invention, or may be blended in the coating composition in the step of forming a coating film. It may be blended in both the step of preparing the composition and the step of forming the coating film.

<Coating composition>
The coating composition according to the present invention is a composition containing fine particles (a), a titanium compound (b) and / or an organosiloxane oligomer (d), and a silane compound (c). Such a coating composition can be produced by hydrolyzing and condensing the silane compound (c) in the presence of at least the fine particles (a), the titanium compound (b) and / or the organosiloxane oligomer (d). it can. Specifically, the following method is mentioned.

(1) When the fine particles (a) are a sol:
After adding the titanium compound (b) and / or the organosiloxane oligomer (d) to the fine particles (a) and stirring the mixture, the silane compound (c) and, if necessary, (e) water and / or an organic solvent, And / or a catalyst (f) for hydrolysis and condensation.

(2) When the fine particles (a) are powder:
After adding (e) water and / or an organic solvent, a titanium compound (b) and / or an organosiloxane oligomer (d) to the fine particles (a) and dispersing them by, for example, a disperser, the silane compound (c) (E) Water and / or an organic solvent and / or a catalyst (f) are added according to the above, followed by hydrolysis and condensation.

に お い て 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 components having low compatibility with the fine particles (a). Here, “lump addition” means adding one kind of component at a time, and “sequential addition” means adding one kind of component over an arbitrary time. When the components (b) to (d) are added all at once, the components (b) to (d) may be added all at once, but the compatibility with the fine particles (a) is taken into consideration. Then, each component may be independently added.

分散 Examples of the dispersing machine used in the production method (2) include an ultrasonic dispersing machine, a ball mill, a sand mill (beads mill), a homogenizer, an ultrasonic homogenizer, a nanomizer, a propeller mixer, and a high shear mixer.

By adding the titanium compound (b) and / or the organosiloxane oligomer (d) to the fine particles (a), the titanium compound (b) and / or the organosiloxane oligomer (d) is adsorbed and / or reacted with the fine particles (a). In addition, the dispersion stability of the fine particles (a) is ensured. In particular, when the fine particles (a) have a strong cohesive force and are hardly dispersed, it is preferable to use the titanium compound (b) and the organosiloxane oligomer (d) in combination.

に お い て In the production method (2), by dispersing the fine particles (a) by a disperser in the presence of the titanium compound (b), the secondary particle size of the fine particles (a) is reduced. Further, the fine particles (a) are adsorbed on the structure represented by the formula (3) of the organosiloxane oligomer (d), so that the particles are fixed in the organosiloxane oligomer (d) and the dispersion stability is secured.

(4) By adding the silane compound (c), the silane compound (c) functions as a binder, and a film can be formed without chalking even when the content of the fine particles (a) is large.

全 The total solid content in the coating 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, storage stability may decrease.

The coating composition according to the present invention can be usually further appropriately prepared according to the purpose of use.For example, it 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. it can.

<Coating film>
The coating film according to the present invention can be formed by forming the coating composition on, for example, the following substrate.

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

These substrates may be subjected to a surface treatment in advance for the purpose of adjusting the base, improving the adhesion, filling the porous substrate, smoothing, and patterning.

Polishing, degreasing, plating, chromate treatment, flame treatment, coupling treatment, etc. as surface treatment for metal-based substrates;
Blasting, chemical treatment, degreasing, flame treatment, oxidation treatment, steam treatment, corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, ion treatment, etc. as surface treatment for plastic base materials;
Polishing, filling, patterning, etc. as surface treatment for inorganic ceramics base materials;
Polishing, filling, insect repellent treatment, etc. as a surface treatment for wood base materials;
Surface treatment for paper base material, such as sealing and insect repellent treatment;
Keren etc. are mentioned as a surface treatment with respect to a deteriorated coating film.

各種 In addition, various primers may be used to ensure adhesion to the base material.

(Coating film forming method)
The method of forming a coating film according to the present invention includes, for example, a method of forming the coating composition on a substrate and then drying the coating film.

As a method of forming the coating composition on a substrate, for example, application using a brush, a roll coater, a bar coater, a flow coater, a centrifugal coater, an ultrasonic coater, a (micro) gravure coater, or the like; dip coating; Coating, spraying, screen process, electrodeposition, vapor deposition and the like.

After forming a coating composition on a base material by these methods, 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 stable coating film is obtained. Can be formed.

When the coating 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 single coating and a dry film thickness of about 0.1 to 40 μm in the case of two coatings is formed. Can be formed.

<Example>
Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to the examples. Parts and% in Examples and Comparative Examples are based on weight unless otherwise specified. The coating composition was evaluated by the following method.

(1) Storage stability:
The coating composition was sealed and stored in a polyethylene bottle at room temperature for one month, and the presence or absence of gelation was visually determined. Viscosity of the non-gelled product was measured using a BM viscometer manufactured by Tokyo Keiki Co., Ltd. The storage stability of the coating composition was evaluated according to the following criteria.

：: The rate of change in viscosity before and after sealed storage is 20% or less ○: The rate of change in viscosity before and after sealed storage exceeds 20% ×: Gel formed after sealed storage (2) Transparency:
The coating composition was diluted with i-propyl alcohol to a solid content concentration of 5%, and ROD. NO. 3 was applied by a bar coater (manufactured by Nippon Cedars Service Co., Ltd.) so that the dry film thickness became 0.2 μm, and then dried at 150 ° C. for 1 hour. The total light transmittance 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.

◎: Total light transmittance of more than 80% ○: Total light transmittance of 60 to 80% ×: Total light transmittance of less than 60% (3) Adhesion:
The coating film produced in the above-described transparency test was subjected to a tape peeling test three times in accordance with a grid test (100 squares) of JIS K5400, and evaluated by an average value of the number of squares that were not peeled.

(4) Superhydrophilization by photocatalysis:
The coating film produced in the above-mentioned transparency test was irradiated with light using a 1.0 mW / cm ² black light fluorescent lamp for 72 hours, and then the contact angle of water was measured.

60 parts of anatase-type titanium oxide as the fine particles (a), 32 parts of a tetra-n-butoxytitanium decamer (trade name: B-10, manufactured by Nippon Soda Co., Ltd.) as the titanium compound (b), and a silane compound (c) ), 200 parts of methyltrimethoxysilane and 41 parts of γ-methacryloxypropyltrimethoxysilane, and 44 parts of isopropyl alcohol as the organic solvent (e) are placed in a container, 300 parts of 0.3 mm zirconia beads are added, and the mixture is bead milled at 1500 rpm. The mixture was stirred and dispersed for one hour. After adding 577 parts of i-propyl alcohol as the organic solvent (e) and removing the beads, 10 parts of di-i-propoxyethyl acetoacetate aluminum and 50 parts of water (e) were added as the catalyst (f), The mixture was heated and stirred at 60 ° C. for 4 hours to obtain a coating composition A having a solid content of about 20%. The storage stability of the obtained composition A is ◎,
The transparency of the coating film was A, the average value of the squares not peeled was 100, and the contact angle of water was 4 degrees.

300 parts of rutile-type titanium oxide having a solid content of about 20% dispersed in isopropyl alcohol as fine particles (a), and dimethylsiloxane oligomer containing alkoxysilyl group / poly (oxyethylene / oxypropylene) group as organosiloxane oligomer (d) ( 29 parts of MAC2101 manufactured by Nippon Unicar Co., Ltd., 200 parts of methyltrimethoxysilane and 19 parts of γ-glycidoxypropyltrimethoxysilane as the silane compound (c), and 413 parts of isopropyl alcohol as the organic solvent (e) After stirring at room temperature for 1 hour, 10 parts of di-i-propoxyethyl acetoacetate aluminum and 43 parts of water (e) were added as a catalyst (f), and the mixture was heated and stirred at 60 ° C. for 4 hours to give a solid content concentration. About 20% of coating composition B was obtained. The storage stability of the obtained composition B was ◎, the transparency of the coating film was ◎, and the average value of the squares not peeled was 100.

60 parts of white conductive titanium oxide (SnO ₂ / Sb-coated TiO ₂ ) as the fine particles (a) and a tetramer of tetra-i-propoxytitanium as a titanium compound (b) (A-10 manufactured by Nippon Soda Co., Ltd.) 32 Parts, 200 parts of methyltrimethoxysilane and 47 parts of dimethyldimethoxysilane as the silane compound (c), and 44 parts of isopropyl alcohol as the organic solvent (e) are placed in a container, and 300 parts of 0.3 mm zirconia beads are added. For 1 hour. After adding 567 parts of i-propyl alcohol as an organic solvent (e) and removing beads, 10 parts of aluminum di-i-propoxyethyl acetoacetate and 50 parts of water (e) were added as a catalyst (f), The mixture was heated and stirred at 60 ° C. for 4 hours to obtain a coating composition C having a solid content of about 20%. The storage stability of the obtained composition C was ◎, the transparency of the coating film was ◎, and the average value of the squares not peeled was 100.

80 parts of cerium oxide as fine particles (a), 42 parts of heptamer of tetra-n-butoxytitanium (B-7 manufactured by Nippon Soda Co., Ltd.) as titanium compound (b), and methyltrimethoxysilane as silane compound (c) 134 parts, 36 parts of an alkoxysilyl group / poly (oxyethylene / oxypropylene) group-containing dimethylsiloxane oligomer (MAC2101 manufactured by Nippon Unicar Co., Ltd.) as an organosiloxane oligomer (d), and isopropyl alcohol 57 as an organic solvent (e) Then, 400 parts of 0.3 mm zirconia beads were added, and the mixture was stirred and dispersed at 1500 rpm for 1 hour by a bead mill. After adding 610 parts of i-propyl alcohol as the organic solvent (e) and removing the beads, 10 parts of di-i-propoxyethylacetoacetate aluminum as the catalyst (f) and 30 parts of water (e) were added. The mixture was heated and stirred at 60 ° C. for 4 hours to obtain a coating composition D having a solid content of about 20%. The storage stability of the obtained composition D was ◎, the transparency of the coating film was ◎, and the average value of the squares not peeled was 100.

80 parts of zirconium oxide as fine particles (a), 42 parts of di-n-butoxybis (acetylacetonato) titanium as titanium compound (b), 134 parts of methyltrimethoxysilane as silane compound (c), and organosiloxane oligomer (d) ), 36 parts of an alkoxysilyl group / poly (oxyethylene / oxypropylene) group-containing dimethylsiloxane oligomer (MAC2101 manufactured by Nippon Unicar Co., Ltd.) and 57 parts of isopropyl alcohol as an organic solvent (e) were placed in a container. 400 parts of 3 mm zirconia beads were added, and the mixture was stirred and dispersed at 1500 rpm for 1 hour by a bead mill. After adding 577 parts of i-propyl alcohol as the organic solvent (e) and removing the beads, di-i-propyl was used as the catalyst (f).
10 parts of propoxyethyl acetoacetate aluminum and 30 parts of water (e) were added, and the mixture was heated and stirred at 60 ° C. for 4 hours to obtain a coating composition E having a solid content of about 20%. The storage stability of the obtained composition E was ◎, the transparency of the coating film was ◎, and the average value of the squares not peeled was 100.

120 parts of anatase-type titanium oxide as the fine particles (a), 28 parts of a tetramer of tetra n-butoxytitanium (B-10 manufactured by Nippon Soda Co., Ltd.) as the titanium compound (b), and methyl as the silane compound (c) 64 parts of trimethoxysilane, 36 parts of a dimethylsiloxane oligomer containing an alkoxysilyl group / poly (oxyethylene / oxypropylene) group (MAC2101 manufactured by Nippon Unicar Co., Ltd.) as an organosiloxane oligomer (d), and an organic solvent (e) 72 parts of propylene glycol monopropyl ether was placed in a container, 500 parts of 0.3 mm zirconia beads were added, and the mixture was stirred and dispersed at 1500 rpm for 1 hour by a bead mill. After adding 660 parts of i-propyl alcohol as the organic solvent (e) and removing the beads, 5 parts of di-i-propoxyethylacetoacetate aluminum and 15 parts of water (e) were added as the catalyst (f), The mixture was heated and stirred at 60 ° C. for 4 hours to obtain a coating composition F having a solid content of about 20%. The storage stability of the obtained composition F was ◎, the transparency of the coating film was ◎, the average value of the squares not peeled was 100, and the contact angle of water was 2 °.

140 parts of anatase-type titanium oxide as the fine particles (a), 28 parts of a tetramer of tetra n-butoxytitanium (B-10 manufactured by Nippon Soda Co., Ltd.) as the titanium compound (b), and methyl as the silane compound (c) 31 parts of trimethoxysilane, 15 parts of γ-methacryloxypropyltrimethoxysilane, and a dimethylsiloxane oligomer containing an alkoxysilyl group / poly (oxyethylene / oxypropylene) group as an organosiloxane oligomer (d) (MAC2101 manufactured by Nippon Unicar Co., Ltd.) ) 24 parts and 72 parts of isopropyl alcohol as an organic solvent (e) were placed in a container, and 600 parts of 0.3 mm zirconia beads were added, and the mixture was stirred and dispersed at 1500 rpm for 1 hour by a bead mill. After adding 680 parts of i-propyl alcohol as an organic solvent (e) and removing the beads, 4 parts of aluminum di-i-propoxyethylacetoacetate and 10 parts of water (e) were added as a catalyst (f), The mixture was heated and stirred at 60 ° C. for 4 hours to obtain a coating composition G having a solid content of about 20%. The storage stability of the obtained composition G was ◎, the transparency of the coating film was ◎, the average value of the squares not peeled was 100, and the contact angle of water was 2 degrees.

<Comparative example>
Container containing 60 parts of anatase type titanium oxide as fine particles (a), 200 parts of methyltrimethoxysilane and 41 parts of γ-methacryloxypropyltrimethoxysilane as silane compound (c), and 44 parts of isopropyl alcohol as organic solvent (e) And 300 parts of 0.3 mm zirconia beads were added, and the mixture was stirred and dispersed at 1500 rpm for 1 hour by a bead mill. After adding 545 parts of i-propyl alcohol as an organic solvent (e) and removing beads, 10 parts of aluminum di-i-propoxyethylacetoacetate and 50 parts of water (e) were added as a catalyst (f), The mixture was heated and stirred at 60 ° C. for 4 hours to obtain a coating composition a having a solid content of about 20%. The storage stability of the obtained composition a was very poor, and it separated and settled after 1 hour of standing (storage stability: x). The transparency of the coating film was x.

塗膜 The coating film formed using the coating composition according to the present invention has high transparency and can be used in a wide range of fields such as optical materials, catalyst materials, electronic materials, sensor materials, and photocatalytic materials.

Claims (5)

(A) metal fine particles and / or metal oxide fine particles,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(Wherein, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ² is an alkyl group having 1 to 6 carbon atoms) 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 a plurality of groups are present, they may be the same or different; m is an integer of 0 to 3 is there)
And at least one titanium compound selected from the group consisting of titanium alcoholate and a derivative thereof represented by the above formula (1), and (c) the following formula (2) )
R ³ _n Si (OR ⁴ ) _4-n (2)
(Wherein, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when two or more are present, they may be the same or different; n is an integer of 0 to 3)
A coating composition comprising at least one silane compound selected from the group consisting of organosilanes and derivatives thereof represented by the formula: (A) metal fine particles and / or metal oxide fine particles,
(C) Formula (2) below
R ³ _n Si (OR ⁴ ) _4-n (2)
(Wherein, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when two or more are present, they 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, having a weight average molecular weight of 300 to 100,000, and Equation (3)
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(Wherein, R ⁵ and R ⁶ represent an alkyl group having 1 to 5 carbon atoms, and when two or more are present, they may be the same or different; R ⁷ is a hydrogen atom or a carbon atom having 1 to 5 carbon atoms. Represents five alkyl groups, and p and q are numbers such that the value of p + q is 2 to 50)
A coating composition comprising an organosiloxane oligomer having a structure represented by the formula: (A) metal fine particles and / or metal oxide fine particles,
(B) The following formula (1)
R ¹ _m Ti (OR ² ) _4-m (1)
(Wherein, R ¹ represents an organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ² is an alkyl group having 1 to 6 carbon atoms) 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 a plurality of groups are present, they may be the same or different; m is an integer of 0 to 3 is there)
A titanium alcoholate and a derivative thereof, and at least one titanium compound selected from the group consisting of a titanium acylate and a derivative thereof represented by the above formula (1),
(C) Formula (2) below
R ³ _n Si (OR ⁴ ) _4-n (2)
(Wherein, R ³ represents a monovalent organic group having 1 to 8 carbon atoms, and when two or more are present, they may be the same or different; R ⁴ has 1 to 5 carbon atoms. Represents an alkyl group or an acyl group having 1 to 6 carbon atoms, and when a plurality of groups are present, they 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, having a weight average molecular weight of 300 to 100,000, and Equation (3)
_{^{- (R 5 O) p -}} (R 6 O) q -R 7 (3)
(Wherein, R ⁵ and R ⁶ represent an alkyl group having 1 to 5 carbon atoms, and when two or more are present, they may be the same or different; R ⁷ is a hydrogen atom or a carbon atom having 1 to 5 carbon atoms. Represents five alkyl groups, and p and q are numbers such that the value of p + q is 2 to 50)
A coating composition comprising an organosiloxane oligomer having a structure represented by the formula: The coating composition according to any one of claims 1 to 3, further comprising a catalyst (f). A coating film obtained from the coating composition according to any one of claims 1 to 4.