JP5108222B2 - Amorphous titanium oxide-containing composite film-forming coating composition, its production method and use - Google Patents

Description

  The present invention relates to a coating composition for forming an amorphous titanium oxide-containing composite film, a method for producing the same, and a use thereof. More specifically, the present invention relates to a coating composition for forming an amorphous titanium oxide-containing composite film that maintains an amorphous state for a long period of time and is easily formed into a coating film, a method for efficiently producing the same, The present invention relates to a composite coating obtained using the composition, an article having the composite coating, and a method for inhibiting crystallization of a titanium alkoxide hydrolysis condensate.

  The hydrolyzed condensate of metal alkoxide can be synthesized at low temperature and has heat resistance, and is therefore used as a coating liquid for forming various coating films. In particular, silane alkoxides are most widely used in terms of ease of handling, cost, abundant types of alkoxides, and the like derived from their reactivity.

  However, a coating film made of a hydrolyzed condensate of silane alkoxide has poor water resistance, and the silica component tends to flow out of the coating film due to moisture, which makes it difficult to use in applications that require water resistance. Therefore, the use of a hydrolysis condensate of titanium alkoxide has been attempted for applications requiring water resistance.

  This titanium alkoxide and / or its partially hydrolyzed condensate is generally extremely reactive, and it is difficult to control the reaction when using an alcohol solvent such as methanol, ethanol, isopropanol or the like that is usually used as a reaction solvent. It tends to cause white precipitation and gelation and is often unsuitable for use as a coating agent component. In order to solve this problem, the present applicant previously used an alcohol having an ether oxygen having 3 or more carbon atoms as a solvent for the hydrolysis and condensation reaction of titanium alkoxide, so that the hydrolysis is relatively stable and has little change with time. An amorphous titanium oxide coating film using the titanium alkoxide hydrolyzed condensate was proposed, which enabled the production of a condensate.

  However, the stability of the hydrolyzed titanium alkoxide condensate obtained by this method is the transesterification reaction between the alcohol having an ether oxygen having 3 or more carbon atoms and the alkoxyl group of the titanium alkoxide and / or the coordination to the titanium atom. Since it relies only on the quasi-equilibrium effect of position-elimination, it was not necessarily sufficient in terms of stabilization.

  In addition, although the hydrolysis condensate of titanium alkoxide is amorphous, it is easily crystallized by the external environment and has higher reactivity (polymerization) and cohesion than silane alkoxide, etc. The pot life is short, the coating film is prone to cracking and whitening, and it is difficult to combine with other components.

On the other hand, Patent Document 1 proposes a coating agent in which a metal alkoxide is hydrolytically condensed in an organic solvent in the presence of an aluminum salt, and further contains an aluminum salt precipitation inhibitor. In this technique, when titanium alkoxide is used as the metal alkoxide, alkylene glycol or a monoether thereof is mixed for the purpose of improving the stability of the titanium alkoxide component. Originally used for the purpose of improving mechanical properties such as film hardness and adhesion when a film is formed, not intended to inhibit the crystallization of the film. It is not intended for the main purpose of controlling reactivity.
In addition, this technique requires that the metal alkoxide is hydrolyzed and condensed in the presence of an aluminum salt.

JP-A-2-258646

  Under such circumstances, the present invention provides a coating composition for forming an amorphous titanium oxide-containing composite film that maintains an amorphous state for a long period of time and can be easily formed into a coating film. It is an object of the present invention to provide a manufacturing method, a composite coating film obtained by using the coating composition, an article having the composite coating film, and a method for inhibiting crystallization of a titanium alkoxide hydrolysis condensate.

  As a result of intensive studies to achieve the above object, the present inventors include (A) a hydrolytic condensate of titanium alkoxide, and (B) a metal compound that can interact with the component (A). The coating liquid can meet the above-mentioned purpose as a coating composition for forming an amorphous titanium oxide-containing composite film, and this coating composition contains a hydrolysis condensate of titanium alkoxide by hydrolyzing titanium alkoxide. After preparing the liquid, it was found that the hydrolyzed condensate-containing liquid and a metal compound capable of interacting with the hydrolyzed condensate can be efficiently manufactured. The invention has been completed.

That is, the present invention
(1) Without containing hydrolyzate of silane alkoxide, (A) General formula (I)
TiR ¹ _x (OR ² ) _4-x (I)
(In the formula, R ¹ represents an alkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group or acyl group, R ² represents an alkyl group having 1 to 6 carbon atoms, and x represents an integer of 0 to 2)
A coating composition for forming an amorphous titanium oxide-containing composite film, comprising a hydrolyzed condensate of titanium alkoxide represented by: (B) aluminum nitrate, and (C) metal compound-based fine particles,
(2) The components (A) and (B) are represented by the following relational formula (II)
5 ≦ {aluminum atom in component (B) / [aluminum atom in component (B) + titanium atom in component (A)]} × 100 ≦ 60 (II)
A coating composition for forming an amorphous titanium oxide-containing composite film according to the above item (1),
(3) The coating composition for forming an amorphous titanium oxide-containing composite film according to the above (1), wherein the metal compound-based fine particles of component (C) are fine particles having a photocatalytic function and / or silica fine particles,
(4) Furthermore, (D) it contains an organic component that can be chemically bonded to amorphous titanium oxide, and the content of the amorphous titanium oxide component is inclined from the surface toward the substrate, and has a self-gradient property. The coating composition for forming an amorphous titanium oxide-containing composite film according to any one of (1) to (3) above, which forms a coating film,
(5) (a) a step of hydrolyzing the titanium alkoxide represented by the general formula (I) in an organic solvent to prepare a hydrolyzed condensate-containing liquid of titanium alkoxide,
(B) a step of mixing the hydrolysis condensate-containing liquid of titanium alkoxide obtained in the step (a) and aluminum nitrate; and (c) a metal compound-based fine particle in the mixture obtained in the step (b). A step of containing,
The method for producing a coating composition for forming an amorphous titanium oxide-containing composite film according to any one of the above items (1) to (4) , comprising:
(6) Amorphous titanium oxide composite obtained by using the coating composition for forming an amorphous titanium oxide-containing composite film according to any one of (1) to (4) above Coating,
(7) An article having the amorphous titanium oxide composite coating film described in (6) above on a substrate,
(8) The article according to (7) above, wherein the amorphous titanium oxide composite coating film is formed as an intermediate layer between an organic compound layer and an inorganic or metal compound layer,
(9) The article according to (7) above, wherein the amorphous titanium oxide composite coating film is on the outermost surface layer and exhibits a photocatalytic function,
(10) The amorphous titanium oxide composite coating film is on the outermost surface layer and exhibits a photocatalytic function, and also exhibits the solid acidity, and (11) a self-tilt as an intermediate layer The article according to (9) or (10), wherein an amorphous titanium oxide composite coating film having a property is provided,
Is to provide.

  According to the present invention, there are provided a coating composition for forming an amorphous titanium oxide-containing composite film that maintains an amorphous state for a long period of time and can be easily formed into a coating film, and a method for efficiently producing the same. be able to. Moreover, the composite coating film obtained using the said coating composition, the articles | goods which have this composite coating film, and the crystallization inhibition method of a titanium alkoxide hydrolysis-condensation product can be provided.

The coating composition for forming an amorphous titanium oxide-containing composite film of the present invention (hereinafter sometimes simply referred to as a coating composition) comprises (A) the general formula (I)
TiR ¹ _x (OR ² ) _4-x (I)
And (B) a metal-based compound capable of interacting with the component (A), comprising a hydrolysis condensate of titanium alkoxide represented by: and (B) at least one selected from inorganic salts, organic salts and alkoxides. It is characterized by including.

In the coating composition of this invention, the hydrolysis condensate of the titanium alkoxide represented by the said general formula (I) is contained as (A) component. In the general formula (I), R ¹ is an alkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group or acyl group, R ² is an alkyl group having 1 to 6 carbon atoms, and x is an integer of 0 to 2. . R ¹ is a non-hydrolyzable group, in which the alkyl group is preferably an alkyl group having 1 to 20 carbon atoms, and the alkenyl group and the alkynyl group are preferably those having 2 to 20 carbon atoms. The aryl group preferably has 6 to 20 carbon atoms, and the aralkyl group preferably has 7 to 20 carbon atoms. Furthermore, as an acyl group, a C2-C20 aliphatic acyl group and a C7-C20 aromatic acyl group (aroyl group) can be mentioned preferably.

On the other hand, OR ² is a hydrolyzable group, and the alkyl group having 1 to 6 carbon atoms represented by R ² may be linear, branched or cyclic. Examples thereof include methyl Group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, cyclopentyl group, cyclohexyl group and the like. x is an integer of 0 to 2, when R ¹ are a plurality, each R ¹ may be mutually identical or different and, where OR ² there are a plurality, each OR ² is another May be the same or different.

  Among the titanium alkoxides represented by the general formula (I), titanium tetraalkoxide is preferable. Examples of the titanium tetraalkoxide include titanium tetramethoxide, titanium tetraethoxide, titanium tetra-n-propoxide, titanium tetraalkoxide. Preferable examples include isopropoxide, titanium tetra-n-butoxide, titanium tetraisobutoxide, titanium tetra-sec-butoxide, and titanium tetra-tert-butoxide. These may be used individually by 1 type and may be used in combination of 2 or more type.

  An organic solvent is used in the coating composition of the present invention. As the organic solvent, alcohols are preferable, and alcohols having an etheric oxygen having 3 or more carbon atoms are more preferable from the viewpoint of controlling the hydrolysis-condensation reaction and stabilizing the condensate. Examples of alcohols having ether oxygen having 3 or more carbon atoms include solvents having an interaction with titanium alkoxide, such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, and the like. Cellosolve solvents such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether . Among these, cellosolve solvents are particularly preferable. These solvents may be used singly or in combination of two or more.

  The hydrolysis-condensation reaction of titanium tetraalkoxide is preferably 4 to 20 times mol, more preferably 5 to 12 times mol of the alcohol, and preferably 0.5 or more and less than 4 times mol of titanium tetraalkoxide. More preferably, it is carried out at a temperature in the range of usually 0 to 70 ° C., preferably 20 to 50 ° C. in the presence of an acidic catalyst such as hydrochloric acid, sulfuric acid and nitric acid, using 1 to 3.0 moles of water. An acidic catalyst is 0.1-1.0 times mole normally with respect to titanium tetraalkoxide, Preferably it is used in 0.2-0.7 times mole.

  In the coating composition of the present invention, the component (B) contains at least one selected from inorganic salts, organic salts and alkoxides and contains a metal compound capable of interacting with the component (A). To do. This metal compound of component (B) is a component contained in order to express the reaction suppression and crystallization inhibitory action of the hydrolysis condensate of titanium alkoxide as component (A).

  Specific examples of the metal compound include salts of nitric acid, acetic acid, sulfuric acid, aluminum chloride and zirconium, hydrates of these inorganic salts, aluminum chelates such as aluminum triacetylacetonate, tetra-n-propoxy, and the like. Examples thereof include metal alkoxides such as zirconium, tetraethoxysilane, and phenyltrimethoxysilane, hydrolysates of these compounds, and condensates thereof. Of these, aluminum compounds are preferable, and aluminum nitrate and hydrates thereof are particularly preferable. The said metal type compound may be used individually by 1 type, and may be used in combination of 2 or more type.

  In the metal-based compound, a plate-like, rod-like, or particle-like sol having a certain size from the beginning is unlikely to exhibit the above action, and a molecular-level compound can effectively express the action.

  The metal compound is added after the hydrolysis condensate of titanium alkoxide has been generated. When a titanium alkoxide is subjected to a hydrolytic condensation reaction in the presence of the metal compound, the progress of the hydrolytic condensation reaction of the titanium alkoxide is greatly hindered, and a long time is required to cause the reaction to a desired molecular weight.

In the coating composition of the present invention, as the content ratio of the component (A) and the component (B), for example, when an aluminum compound such as aluminum nitrate is used as the component (B), the following relational formula (II)
5 ≦ {aluminum atom in component (B) / [aluminum atom in component (B) + titanium atom in component (A)]} × 100 ≦ 60 (II)
It is preferable that it is the ratio which satisfy | fills.

  When the value of the formula (II) is less than 5, it is difficult to obtain the reaction suppressing effect and crystallization inhibiting effect of the titanium alkoxide hydrolysis condensate. On the other hand, when it exceeds 60, the inherent properties of amorphous titanium oxide are impaired. May occur. A more preferable value of the ratio is in the range of 10-50.

In the coating composition of this invention, a metal compound type fine particle can be contained as (C) component as needed. Specifically, the metal compound-based fine particles are not particularly limited as long as they can withstand practical use, such as being chemically stable, readily available, and inexpensive, but TiO ₂ , SiO _{2 2} , Al ₂ O ₃ , WO ₃ , ZnO, SrTiO ₃ , CdS, GaP, InP, In ₂ O ₃ , GaAs, BaTiO ₃ , KNbO ₃ , Fe ₂ O ₃ , Ta ₂ O ₅ , SnO ₂ , Bi ₂ O ₃ , NiO, CuO, SiC, MoS ₂ , InPb, and the like.

These can be broadly classified into those having an anionic zeta potential in water with a pH of 7 as solid acidity and those showing a cationic property as solid basicity. Specifically, SiO ₂ , WO ₃ , TiO _{2 and the} like are listed as those showing solid acidity, and Al ₂ O _{3 and the} like are shown as showing solid basicity.

Particularly in the present invention, the metal compound-based fine particles include fine particles having a photocatalytic function and / or silica fine particles, particularly colloidal silica. The content is preferably in the range of 5 to 50% by mass of fine particles having a photocatalytic function and 25 to 75% by mass of colloidal silica. If the content of fine particles having a photocatalytic function is less than 5% by mass, the ability to decompose organic substances as a photocatalyst film and the ability to superhydrophilize cannot be sufficiently exhibited. On the other hand, if the content exceeds 50% by mass, the photocatalytic activity is improved. When other metal compound fine particles are used in combination, the content is relatively low. For example, in the case of using colloidal silica together, the removal ability by adsorption of basic substances is reduced, and the photocatalyst particles This is not practically useful because the ability to decompose is not fully utilized, or the ability to maintain superhydrophilicity in a dark place is likely to be low because water retention is reduced.
As the fine particles having a photocatalytic function, titanium oxide particles mainly composed of anatase type crystals can be preferably used.

  The titanium oxide fine particles containing the anatase crystal as a main component (hereinafter sometimes referred to as anatase crystal titanium oxide particles) are photocatalyst particles, and may contain a small amount of rutile crystals and have a silica surface. For example, it may be partially or wholly covered. Further, visible light responsive photocatalyst particles partially including titanium nitride, low-order titanium oxide, and the like can also be used. The average particle diameter of the anatase crystalline titanium oxide particles is preferably in the range of 1 to 500 nm, more preferably in the range of 1 to 100 nm, and most preferably in the range of 1 to 50 nm because of having an excellent photocatalytic function. The average particle diameter can be measured by a scattering method using laser light.

  Further, at least one selected from the group consisting of V, Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ag, Pt, and Au as the second component inside and / or on the surface of the titanium oxide particles. It is preferable to include a seed metal and / or metal compound because it has a higher photocatalytic function. Examples of the metal compound include metal oxides, hydroxides, oxyhydroxides, sulfates, halides, nitrates, and metal ions. The content of the second component is appropriately selected according to the type of the substance.

  The anatase crystalline titanium oxide particles can be produced by a conventionally known method, but it is advantageous to use the titanium oxide sol in the form of a titanium oxide sol so as to be homogeneously dispersed in the coating liquid. In order to produce the titanium oxide sol, for example, powdered anatase crystalline titanium oxide may be dissolved in the presence of an acid or alkali, or the particle diameter may be controlled by pulverization. In addition, the hydrous or neutralized decomposition of titanium sulfate or titanium chloride may be used to control the crystallite size and particle size by physical and chemical methods. Furthermore, a dispersion stabilizer can be used to impart dispersion stability in the sol solution.

  On the other hand, colloidal silica has a function of causing the photocatalytic film to exhibit superhydrophilicity maintaining performance even in a dark place.

  A photocatalyst exhibits the property of decomposing an organic substance existing on the surface thereof by irradiation with light such as ultraviolet rays and superhydrophilicity, but generally does not exhibit such a photocatalytic function in a dark place. However, by incorporating colloidal silica in the photocatalyst film as in the present invention, the photocatalyst film exhibits superhydrophilic maintenance performance even in a dark place.

  In addition, the coating composition of the present invention contains anatase-type titanium oxide fine particles and colloidal silica as the component (C), and uses its photocatalytic function to purify waste liquid particularly for the purpose of removal by adsorption of basic substances. When used for applications or the like, colloidal silica preferably has a zeta potential of less than −20 mV, more preferably less than −40 mV in the neutral region. On the other hand, a zeta potential in the neutral region of −20 mV or higher can be understood as having a low surface energy. These also have good wettability in organic solvents with low surface energy, and since the surface charge is small, the interaction with the hydrolysis condensate of titanium alkoxide is weak, and it is relatively difficult in organic solvent coating liquids. Stability is considered high. However, on the other hand, since the surface charge is small, there arises a problem that the ability to remove the basic substance after coating is poor.

  In addition, when aiming at imparting antifouling properties utilizing the superhydrophilic function, there is no particular problem since the water retention is sufficient even when the zeta potential of the colloidal silica is -20 mV or higher. When obtaining a composite coating film having a component gradient structure in which the content of the metal compound fine particles continuously changes in the depth direction from the surface of the coating film, titanium alkoxide hydrolysis such as colloidal silica having a zeta potential of -20 mV or more. The composite coating film can be easily produced by selecting one having a small interaction with the condensate.

This colloidal silica is a product in which high-purity silicon dioxide (SiO ₂ ) is dispersed in water or an alcohol solvent to form a colloid, and the average particle size is usually in the range of 1 to 200 nm, preferably 5 to 50 nm. It is. In the hydrolysis condensate of silicon alkoxide, since the reaction is not terminated, it is easily eluted with water, and the photocatalytic film containing it is inferior in water resistance. On the other hand, colloidal silica is a reaction-terminated fine particle, so it is difficult to elute with water, and a photocatalyst film containing it has good water resistance.

  In addition to the effect of improving the strength and hardness of the coating film, this colloidal silica may also exhibit the effect of making the surface uneven.

  When the photocatalytic function is imparted to the coating composition of the present invention, the liquid containing the hydrolysis condensate of titanium alkoxide (A) and the metal compound (B) is added as the component (C). It can be prepared by adding a predetermined amount of anatase crystalline titanium oxide sol and optionally colloidal silica and uniformly dispersing.

  The coating composition having the photocatalytic function prepared in this manner is applied to a suitable substrate by a known method such as dip coating, spin coating, spray coating, bar coating, knife coating, roll coating. The desired photocatalyst film can be obtained by coating by a blade coating method, a die coating method, a gravure coating method, and the like, followed by natural drying or heat drying. In the case of heat drying, a temperature of 200 ° C. or lower can be adopted. Thus, after the film formation, the formed photocatalyst film can exhibit a sufficient photocatalytic function by holding treatment at a low temperature, and as a substrate, for example, heat resistance of ceramics, glass, metal, alloy, etc. In addition to an inorganic base material excellent in heat resistance, an organic base material inferior in heat resistance can also be suitably used.

  In this way, by using amorphous titanium oxide as the binder component of the photocatalyst film, the crystallization of the binder component is suppressed even when exposed to the accelerated weathering test, resulting in a decrease in mechanical properties and generation of cracks. In addition, a decrease in transparency is suppressed.

  The coating composition of the present invention further includes (D) an organic component that can chemically bond with amorphous titanium oxide, and the content of the amorphous titanium oxide component is inclined from the surface toward the substrate. It can be set as the composition which can form the coating film which has a self-inclination property.

  Examples of the organic component that can be chemically bonded to the amorphous titanium oxide (D) include (a) an ethylenically unsaturated monomer containing no metal and (b) a coupling silicon-containing group. Preferable examples include organic polymer compounds obtained by copolymerizing with ethylenically unsaturated monomers.

  Examples of the ethylenically unsaturated monomer containing no metal as the component (D) (a) include, for example, the general formula (III)

（式中、Ｒ^３は水素原子またはメチル基、Ｘは一価の有機基である。）
で表されるエチレン性不飽和単量体、好ましくは一般式（III−ａ）

(In the formula, R ³ is a hydrogen atom or a methyl group, and X is a monovalent organic group.)
An ethylenically unsaturated monomer represented by the formula (III-a)

（式中、Ｒ^３は水素原子またはメチル基、Ｒ^４は一価の炭化水素基またはエポキシ基、ハロゲン原子若しくはエーテル結合を有する炭化水素基を示す。）
で表されるエチレン性不飽和単量体を一種または二種以上混合して使用しても良い。

(In the formula, R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a monovalent hydrocarbon group, an epoxy group, a halogen atom or a hydrocarbon group having an ether bond.)
One or a mixture of two or more ethylenically unsaturated monomers represented by

In the ethylenically unsaturated monomer represented by the general formula (III-a), the hydrocarbon group represented by R ⁴ includes a linear or branched alkyl group having 1 to 10 carbon atoms, carbon number Preferable examples include 3 to 10 cycloalkyl groups, aryl groups having 6 to 10 carbon atoms, and aralkyl groups having 7 to 10 carbon atoms. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and various butyl groups, pentyl groups, hexyl groups, octyl groups, and decyl groups. Examples of the cycloalkyl group having 3 to 10 carbon atoms include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, and a cyclooctyl group. Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group, a tolyl group, and a xylyl group. Examples of the aralkyl group having 7 to 10 carbon atoms, such as a group, a naphthyl group, and a methylnaphthyl group, include a benzyl group, a methylbenzyl group, a phenethylyl group, and a naphthylmethyl group. Examples of the hydrocarbon group having an epoxy group, a halogen atom or an ether bond include a linear or branched alkyl group having 1 to 10 carbon atoms and a cycloalkyl group having 3 to 10 carbon atoms having an atom or a bond. Preferred examples include an aryl group having 6 to 10 carbon atoms and an aralkyl group having 7 to 10 carbon atoms. A chlorine atom etc. are mentioned as a halogen atom of the said substituent.

  Examples of the ethylenically unsaturated monomer represented by the general formula (III-a) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl ( (Meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, glycidyl (meth) acrylate, 3-glycidoxypropyl (meth) acrylate, 2- ( 3,4-epoxycyclohexyl) ethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-bromoethyl (meth) acrylate, and the like. These may be used alone or in combination of two or more.

  In addition to these, the ethylenically unsaturated monomer represented by the general formula (III) includes styrene, α-methylstyrene, α-acetoxystyrene, m-, o- or p-bromostyrene, m -, O- or p-chlorostyrene, m-, o- or p-vinylphenol, 1- or 2-vinylnaphthalene and the like, and stabilizers for polymerizable polymers having an ethylenically unsaturated group, for example, ethylenic Antioxidants, ultraviolet absorbers and light stabilizers having an unsaturated group can also be used. These may be used alone or in combination of two or more.

  On the other hand, as the ethylenically unsaturated monomer having a coupling silicon-containing group as component (D) (b), for example, the general formula (IV)

（式中、Ｒ^５は水素原子またはメチル基、Ａは炭素数１〜４のアルキレン基、Ｒ^６はメチル基又はエチル基を示す。）
で表される化合物を好ましく挙げることができる。前記一般式（IV）において、３つのＲ^６はたがいに同一でも異なっていてもよい。

(In the formula, R ⁵ represents a hydrogen atom or a methyl group, A represents an alkylene group having 1 to 4 carbon atoms, and R ⁶ represents a methyl group or an ethyl group.)
Preferred examples include compounds represented by: In the general formula (IV), three R ⁶ may be the same or different.

Examples of the ethylenically unsaturated monomer represented by the general formula (IV) include 2- (meth) acryloxyethyltrimethoxysilane, 2- (meth) acryloxyethyltriethoxysilane, γ- (meta ) Acryloxypropyltrimethoxysilane, γ- (meth) acryloxypropyltriethoxysilane, and the like.
The ethylenically unsaturated monomer having a coupling silicon-containing group as component (b) may be used alone or in combination of two or more.

  In the presence of a radical polymerization initiator, the ethylenically unsaturated monomer containing no metal of the component (a) and the ethylenically unsaturated monomer having a coupling silicon-containing group of the component (b), By radical polymerization, an organic polymer compound having a coupling silicon-containing group used as a component of the component (D) can be obtained.

  In the present invention, a solution obtained by dissolving the organic polymer compound having a coupling silicon-containing group as component (D) thus obtained in an appropriate solvent such as alcohol, ketone, ether, and the like, By mixing the hydrolyzed condensate of the titanium alkoxide as the component (A), the metal compound as the component (B), and a liquid containing the metal compound fine particles as the component (C) if necessary. Coupling silicon-containing group in organic polymer compound hydrolyzes, reacts selectively with hydrolysis condensate of titanium alkoxide in reaction liquid of component (A), and coating for coating film formation having self-gradient property A composition is obtained. In this case, as a diluting solvent for the reaction solution containing the hydrolysis condensate of titanium alkoxide used, it is desirable to use a solvent containing an alcohol having an ether oxygen having 3 or more carbon atoms for the reason described above.

  By using such a coating composition, when applied to an organic substrate and dried, the organic substrate side is substantially an organic polymer compound component and the opposite side is an amorphous titanium oxide component. A coating film having a good component gradient structure in which the content ratio continuously changes in the film thickness direction can be stably formed.

  This self-grading coating film contains an amorphous titanium oxide component as an inorganic component, so that crystallization of the inorganic component is suppressed even when exposed under an accelerated weathering test, resulting in a decrease in mechanical properties, cracks, and the like. Occurrence of, and a decrease in transparency are suppressed.

  In order to form a coating film having a self-gradient property on an organic substrate, the coating composition of the present invention thus obtained has a dry coating thickness of usually 5 μm or less, preferably 0. Dip coating method, spin coating method, spray coating method, bar coating method, knife coating method, roll coating method, blade coating method so as to be in the range of 01 to 1.0 μm, more preferably 0.02 to 0.7 μm. It is applied by a known means such as a die coating method or a gravure coating method, and the solvent is evaporated to form a coating film.

  Examples of the organic base material include acrylic resins such as polymethyl methacrylate, styrene resins such as polystyrene and ABS resins, olefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, and 6-nylon. Examples include substrates made of polyamide resins such as 1,6,6-nylon, polyvinyl chloride resins, polycarbonate resins, polyphenylene sulfide resins, polyphenylene ether resins, polyimide resins, and cellulose resins such as cellulose acetate. be able to.

  These organic base materials can be subjected to surface treatment by an oxidation method, an unevenness method, or the like, if desired, in order to further improve the adhesion with the coating film having a self-gradient according to the present invention. Examples of the oxidation method include corona discharge treatment, chromic acid treatment (wet), flame treatment, hot air treatment, ozone / ultraviolet irradiation treatment and the like, and examples of the unevenness method include sand blast method and solvent treatment method. Is mentioned. These surface treatment methods are appropriately selected according to the type of substrate.

  In addition, the organic base material in this invention has an organic coating film on the surface of the base material which consists of materials other than organic type materials, for example, metal-type material, glass, ceramics-type material, and other various inorganic type or metal-type materials. Also included.

  In addition, confirmation of the inclined structure of the coating film can be achieved by, for example, sputtering the coating film surface to scrape the film and measuring the carbon atom and titanium atom content on the film surface over time by X-ray photoelectron spectroscopy. Can be done.

  Although there is no restriction | limiting in particular as content of the metal component in the coating film which has this self-gradient property, Usually 5 to 98 weight% in conversion of a metal oxide, Preferably it is 20 to 98 weight%, Most preferably, it is 50 to 95 weight%. % Range. The degree of polymerization and the molecular weight of the organic polymer compound are not particularly limited as long as they can be formed into a film, and may be appropriately selected according to the kind of polymer compound and desired coating film properties.

Next, the method for producing a coating composition for forming an amorphous titanium oxide-containing composite film of the present invention comprises:
(A) a step of hydrolyzing the titanium alkoxide represented by the general formula (I) in an organic solvent to prepare a hydrolyzed condensate-containing liquid of titanium alkoxide; and (b) obtained in the step (a). A liquid containing a hydrolyzed condensate of titanium alkoxide and a metal compound comprising at least one selected from inorganic salts, organic salts and alkoxides and capable of interacting with the hydrolyzed condensate of titanium alkoxide. Mixing,
It is characterized by including.

  In the step (a), as the organic solvent used for the hydrolysis-condensation reaction of titanium alkoxide, alcohols having ether-based oxygen having 3 or more carbon atoms exemplified above are suitable. The hydrolysis-condensation conditions are as described above.

  In the method of the present invention, in the next step (b), the titanium alkoxide hydrolyzed condensate-containing liquid obtained in the step (a) and a metal compound capable of interacting with the hydrolyzed condensate, preferably Is mixed with an aluminum compound such as aluminum nitrate.

  In the step (a), when the hydrolysis-condensation reaction of the titanium alkoxide is performed in the presence of the metal compound, the progress of the hydrolysis-condensation reaction of the titanium alkoxide is largely hindered, and the reaction is performed to a desired molecular weight. Therefore, a long time is required.

  In the method of the present invention, the coating composition obtained as described above is optionally added to the metal compound fine particles described as the component (C) and / or the amorphous oxide described as the component (D). An organic component that can be chemically bonded to titanium can be contained.

  The present invention also provides an amorphous titanium oxide composite coating film obtained using the above-described coating composition for forming an amorphous titanium oxide-containing composite film of the present invention, and the amorphous titanium oxide composite on a substrate. Articles having a coating are also provided.

  The article preferably has an amorphous titanium oxide composite coating film formed as an intermediate layer between an organic compound layer and an inorganic or metal compound layer.

  Further, an article having an amorphous titanium oxide composite coating film on the outermost surface layer and exhibiting a photocatalytic function is preferable, and in particular, an amorphous titanium oxide composite coating film is present on the outermost surface layer and exhibiting a photocatalytic function. In addition, an article exhibiting solid acidity is suitable from the viewpoint of, for example, waste liquid purification use.

  Furthermore, in an article in which the outermost surface layer has a photocatalytic function, it is preferable that an amorphous titanium oxide composite coating film having a self-gradient property is provided as an intermediate layer.

  In this case, the coating composition of the present invention having the photocatalytic function described above is applied on the composite coating film having the self-gradient property formed using the coating composition of the present invention, and the film is formed at a temperature of 200 ° C. or lower. A photocatalyst layer can be provided by holding treatment at temperature. The thickness of this photocatalyst layer is usually selected in the range of 10 nm to 5 μm. If the thickness is less than 10 nm, the photocatalytic function is not sufficiently exerted, and if it exceeds 5 μm, the effect of improving the photocatalytic function is not recognized for the thickness, but rather causes cracking. A preferred thickness is 20 nm to 2 μm, and a range of 20 nm to 1 μm is particularly preferable.

  The photocatalyst layer formed in this way is particularly excellent in photocatalytic functions such as superhydrophilicity and superhydrophilicity maintenance performance in a dark place, and has good water resistance and mechanical strength. It has good durability that can be held over.

  In the present invention, by using the amorphous titanium oxide as an inorganic component of a composite coating film having a self-gradient property or a binder component of a photocatalyst layer, the inorganic component or binder is exposed even under an accelerated weathering test. Since the crystallization of the component is suppressed, it is possible to greatly suppress the deterioration of mechanical properties. Moreover, generation | occurrence | production of a crack is suppressed and long-term transparency can be maintained.

  There are no particular restrictions on the type of substrate used in the article of the present invention, and both organic and inorganic substrates can be used. However, when providing a composite coating film having self-gradient properties, as described above. An organic substrate is used.

  The present invention also comprises (A) the hydrolysis condensate of titanium alkoxide represented by the general formula (I), comprising (B) at least one selected from inorganic salts, organic salts and alkoxides, and There is also provided a method for inhibiting crystallization of a hydrolysis condensate of titanium alkoxide, which comprises mixing a metal compound capable of interacting with the component (A).

By mixing a metal compound capable of interacting with the component (A), the present invention has the following effects.
(1) The hydrolysis condensate of titanium alkoxide becomes difficult to crystallize and can maintain an amorphous state.
(2) The hydrolysis condensate of titanium alkoxide becomes difficult to be polymerized.
(3) By the above (2), the rapid contraction generated in the coating film after forming the coating liquid is prevented, cracks are hardly generated, and the coating agent can be stably formed into a film.
(4) By the above (2), the hydrolysis condensate of titanium alkoxide in the coating liquid is stabilized, and the pot life of the liquid is prolonged.
(5) According to the above (2), even if a third component that reacts with the hydrolysis condensate of titanium alkoxide is combined in the coating solution, it becomes difficult to react and integrate.
(6) According to the above (5), when a metal oxide fine particle such as silica is added to form a film, the metal oxide fine particle surface is not covered with a hydrolysis condensate of titanium alkoxide. Can be present on the outermost surface of the membrane.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.

Various characteristics were determined according to the following methods.
(1) Light Scattering Intensity Measurement of Titanium Alkoxide Hydrolysis Condensate The light scattering intensity of the titanium alkoxide hydrolysis condensate was measured using a zeta potential measuring device “ELS-8000” manufactured by Otsuka Electronics Co., Ltd.
The light scattering intensity is represented by the following formula (a) (I _S = light scattering intensity, I _O = incident light intensity, n = refractive index of solvent, M _W = weight average molecular weight of solute, c = solute concentration) , (dn / dc) = refractive index increment per increase the concentration of the solute, lambda _O = incident light wavelength, the distance from r = sample to the detector, _{N a} = Avogadro's number), molecular size corresponding to _{M W,} i.e. A value proportional to the growth of the sol is observed.

(2) Z potential of metal compound-based fine particles After diluting a metal compound-based fine particle dispersion 100 times with pure water, pH is adjusted with 0.01 mol / L hydrochloric acid aqueous solution or 0.01 mol / L sodium hydroxide aqueous solution. = 7. Thereafter, the surface potential of the fine particles was measured using a zeta potential measuring device (“ELS-8000” manufactured by Otsuka Electronics Co., Ltd.).

(3) Stability of coating solution After preparing the coating solution, leave it at room temperature (15-20 ° C), observe the state of the coating solution after 3 days, and if precipitation or gelation occurs X: No precipitation or gelation, but white turbidity or chromaticity is evaluated as △, slight turbidity or chromaticity is evaluated as ◯, and evaluation is evaluated as ◎ when almost no change is observed. did.

(4) Adsorption characteristic of methylene blue of photocatalyst-containing film Using the basic dye methylene blue, the adsorption characteristic of the photocatalyst-containing film to a basic substance was evaluated.
Specifically, the prepared photocatalyst-containing supported glass mat was put in a petri dish having a diameter of 8 cm, 50 mL of a 100 ppm concentration of methylene blue aqueous solution was added, and the mixture was allowed to stand in the dark for 3 days while being covered and stirred. Thereafter, the aqueous solution in the petri dish was taken out, and the concentration C of the methylene blue aqueous solution was measured by the ABS method. Based on the obtained results, the distribution coefficient K was determined according to the following equation (b). If the analyte has a strong adsorption characteristic for methylene blue, the partition coefficient K increases, and an excellent adsorption characteristic is exhibited when K ≧ 10.
Partition coefficient K = (100 ppm−concentration Cppm) / concentration Cppm (b)

(5) Adsorption characteristics of sunset yellow of photocatalyst-containing film Using the acid dye Sunset Yellow, the adsorption characteristics of the photocatalyst-containing film to acidic substances were evaluated.
Specifically, the prepared photocatalyst-containing supported glass mat was put in a petri dish having a diameter of 8 cm, 50 mL of a sunset yellow aqueous solution having a concentration of 100 ppm was added, and the mixture was allowed to stand in the dark for 3 days while being covered and stirred. Thereafter, the aqueous solution in the petri dish was taken out, and the concentration C of the sunset yellow aqueous solution was measured by the ABS method. Based on the obtained results, the distribution coefficient K was determined according to the following equation (c). If the analyte has a strong adsorption characteristic for sunset yellow, the distribution coefficient K increases, and an excellent adsorption characteristic is exhibited when K ≧ 10.
Partition coefficient K = (100 ppm-concentration Cppm) / concentration Cppm (c)

(6) Gradient About the gradient structure of the component gradient film, using XPS (“PHI-5600” manufactured by ULVAC-PHI Co., Ltd.), argon sputtering 4 kV is applied at intervals of 3 minutes, and the film surface is carbonized. The content of atoms and metal atoms was examined by measuring by X-ray electron spectroscopy.

(7) Weather resistance evaluation After a 1500-hour accelerated weather resistance test using a carbon arc sunshine weather meter (SWM) was performed on a PET film in which a component gradient film and a photocatalyst-containing film were sequentially laminated, the haze value of the film before and after the accelerated weather resistance test The degree of increase (according to JISK 7361) was examined. The SWM test conditions are shown below. In general, a proportional correlation is recognized between the degree of occurrence of cracks in the coating film and the haze value. It is thought that cracks are mainly caused by shrinkage in the surface direction accompanying the reaction of amorphous titanium oxide.

<SWM test conditions>
(Device name) Suga Test Instruments Co., Ltd. “Sunshine Weather Meter S300”
(Measurement conditions) Illuminance: 255 ± 25 W / m ² , cycle: 102 minutes of irradiation, 2 hours and 1 cycle of irradiation + rainfall 18 minutes, BPT: 63 ± 3 ° C., relative humidity: 55 ± 5% RH

Synthesis Example 1 Synthesis of Titanium Alkoxide Hydrolysis Condensate To 149 g of ethyl cellosolve, 75.7 g of titanium tetraisopropoxide (trade name: A-1, manufactured by Nippon Soda Co., Ltd.) was slowly added dropwise with stirring to a solution ( A) was obtained. To this solution (A), a mixed solution of 58.3 g of ethyl cellosolve, 4.55 g of distilled water and 12.6 g of 60 mass% concentrated nitric acid was added dropwise with stirring to obtain a solution (B). The solution (B) was then stirred at 30 ° C. for 4 hours to obtain a titanium alkoxide hydrolysis-condensation liquid (C).
The light scattering intensity of this solution was measured and found to be about 13000 cps.

Synthesis Example 2 Synthesis of Organic Components To a 1 L separable flask, 424.0 g of methyl isobutyl ketone, 200.0 g of methyl methacrylate, and 25.3 g of methacryloxypropyltrimethoxysilane were added in a nitrogen atmosphere, and the temperature was raised to 60 ° C. A methyl isobutyl ketone solution in which 1.9 g of azobisisobutyronitrile was dissolved was dropped into this mixed solution to start the polymerization reaction, and the mixture was stirred for 30 hours to obtain an organic component solution (G).

Reference Example 1 Measurement of Light Scattering Intensity of Hydrolysis Condensation Solution of Titanium Alkoxide Mixed with Aluminum Nitrate / Nohydrate Hydrolysis Condensation Solution (C) Prepared in Synthesis Example 1 and Aluminum Nitrate / Ninehydrate (Purity 99% , Manufactured by Wako Pure Chemical Industries, Ltd.), the solid content obtained from the former is regarded as TiO ₂ , and the solid content obtained from the latter is regarded as Al (NO ₃ ) _3. Thus, the liquid diluted with ethyl cellosolve was prepared, and the light scattering intensity after stirring at room temperature for 70 hours was measured.

  The results are shown in Test Example No. 1 in Table 1. As shown in 1 to 7, it was found that the addition of aluminum nitrate nonahydrate suppresses the increase in light scattering intensity (≈sol growth) of the hydrolysis condensate of titanium alkoxide. Here, Test Example No. Since Nos. 4 to 6 are systems containing a hydrolysis condensate of titanium alkoxide and aluminum nitrate nonahydrate, they correspond to the examples of the present invention.

  In the system containing only aluminum nitrate nonahydrate (Test Example 7), the light scattering intensity showed a value of 1000 cps or less, and almost no increase in the value was observed. Normally, even when only a clean solvent is measured, the light scattering intensity is 1000 cps or less. That is, it can be interpreted that aluminum nitrate nonahydrate is not observed in the measurement. In other words, it is considered that the increase in the light scattering intensity captures only the growth of the hydrolysis condensate of titanium alkoxide.

<Investigation of the effect of water addition during titanium alkoxide hydrolysis condensation>
Reference example 2
To 453 g of ethyl cellosolve, 230 g of titanium tetraisopropoxide (trade name: A-1, manufactured by Nippon Soda Co., Ltd.) was slowly added dropwise with stirring to obtain a solution. While this solution was stirred in a 30 ° C. warm bath, a mixed solution of 177 g of ethyl cellosolve, 13.8 g of distilled water and 38.4 g of 60% by mass concentrated nitric acid was added dropwise to obtain a solution (S1).
When the light scattering intensity of this solution was measured, the value immediately after preparation was about 9000 cps, and the solution (S1 ′) after stirring for 4 hours showed a value of about 14500 cps, and the increase in light scattering intensity was 1375 cps / h.

Reference example 3
A titanium alkoxide hydrolytic condensate (S2) was obtained in the same manner as in Reference Example 2 except that the distilled water was changed to 20.7 g.
When the light scattering intensity of this solution was measured, the value immediately after preparation was about 9500 cps, and the solution after stirring for 4 hours (S2 ′) showed a value of about 23500 cps, and the increase in light scattering intensity was 3500 cps / h.
From the results of Reference Example 2 and Reference Example 3, it is clear that the addition rate of water greatly affects the hydrolysis condensation reaction of titanium alkoxide.
Therefore, in the following Reference Examples 4 and 5, the amount of water added was the same for both, and the light scattering intensity of the obtained reaction products was compared. In addition, since the aluminum nitrate used here is a nonahydrate and it is thought that this moisture content is also concerned in reaction, the addition amount of water was adjusted also considering the moisture content.

<Influence of timing of addition of aluminum nitrate>
Reference example 4
A solution obtained by dissolving 16 g of aluminum nitrate nonahydrate in 30 g of ethyl cellosolve was added to the solution (S1 ′) obtained in Reference Example 2, and the mixture was further stirred for 11 hours, and stirred for a total of 15 hours. (T3) was obtained. (The final amount of water added in this case is 20.7 g).
The light scattering intensity of this solution was measured and found to be about 16500 cps. Stirring was further continued, and stirring was carried out for a total of 30 hours. As a result, it was 18000 cps.

Reference Example 5
To 453 g of ethyl cellosolve, 230 g of titanium tetraisopropoxide (trade name: A-1, manufactured by Nippon Soda Co., Ltd.) was slowly added dropwise with stirring to obtain a solution. While this solution was stirred in a 30 ° C. warm bath, a mixed solution of 177 g of ethyl cellosolve, 6.9 g of distilled water, 38.4 g of 60 mass% concentrated nitric acid, and 16 g of aluminum nitrate nonahydrate was added dropwise. (S4) was obtained. (The amount of water added at this stage is 13.8 g).
When the light scattering intensity of this solution was measured, it was about 9000 cps immediately after the preparation, and the light scattering intensity of the solution (S4 ′) after stirring for 4 hours was about 12400 cps.

Further, 30 g of ethyl cellosolve and 6.9 g of distilled water were added dropwise to this solution, and the mixture was further stirred for 11 hours, and stirred for a total of 15 hours to obtain a solution (T4). (The final amount of water added in this case is 20.7 g).
The light scattering intensity of this solution was measured and found to be about 15000 cps. Stirring was further continued, and stirring was carried out for a total of 30 hours. As a result, it was 17800 cps.

The results of Reference Examples 4 and 5 are shown in Table 2.
From the above results, when the hydrolysis-condensation reaction of titanium alkoxide is carried out in the presence of aluminum nitrate, it takes a lot of time to grow to a certain size. When the content of aluminum nitrate in Reference Examples 4 and 5 is calculated according to the formula (II), both are 5 mol%, but it goes without saying that if the content is higher than this, more reaction time is required. come.

Example 1
(1) Preparation of coating solution 1.23 g of aluminum nitrate nonahydrate (purity 99%, manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 35.1 g of ethyl cellosolve, and then prepared in Synthesis Example 1. 3.66 g of the synthesis liquid (C) was added and stirred well to obtain a solution (D-1).
34 g of the solution (D-1) was added to a mixed solvent of 332 g of ethyl cellosolve and 365 g of 1-propanol and stirred well. Next, 7.56 g of distilled water and 3.36 g of 60 mass% concentrated nitric acid were added and stirred well, followed by anatase type photocatalytic titanium oxide sol (trade name PC-203, concentration 20 mass%, manufactured by Titanium Industry Co., Ltd.). 14.3 g was added and stirred well to obtain a solution (E-1).
43.8 g of silica sol (trade name Snowtex OXS, concentration 10 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −50 mV at pH = 7.0 may be added to the solution (E-1). The mixture was stirred to prepare a photocatalyst-containing coating liquid (F-1).
When the coating liquid (F-1) was allowed to stand at room temperature for 3 days, no abnormality was observed except that the cloudiness was slightly increased.

(2) Production and Evaluation of Photocatalyst-Containing Film-Supporting Glass Mat Glass mat produced by the needle punch method (weight per unit of 750 g / m ² , thickness 12 mm, manufactured by Chubu Kogyo Co., Ltd.) is cut into a square 5 cm long and 5 cm wide (mass) About 2 g) and treated at 400 ° C. for 1 day. After the heat treatment, the glass mat cooled to room temperature was immersed in the photocatalyst-containing coating liquid (F-1) for 10 minutes, and squeezed with a roller so that the glass mat containing the coating liquid became 8 g.
The glass mat was dried at 120 ° C. for 12 hours, then exposed to an atmosphere of 80 ° C. and 80% humidity for 24 hours, and then dried again at 120 ° C. for 15 hours to obtain a sample.
As a result of examining methylene blue adsorption characteristics of the produced photocatalyst-containing film-supported glass mat, the distribution coefficient K was 16.

Example 2
(1) Preparation of coating solution 0.50 g of aluminum nitrate nonahydrate (purity 99%, manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 23.5 g of ethyl cellosolve, and then prepared in Synthesis Example 1. 6.04 g of the synthesis solution (C) was added and stirred well to obtain a solution (D-2).
To a mixed solvent of 342 g of ethyl cellosolve and 365 g of 1-propanol, 23.7 g of the solution (D-2) was added and stirred well. Next, 7.84 g of distilled water and 3.29 g of 60 mass% concentrated nitric acid were added and stirred well, followed by anatase type photocatalytic titanium oxide sol (trade name PC-203, concentration 20 mass%, manufactured by Titanium Industry Co., Ltd.). 14.3 g was added and stirred well to obtain a solution (E-2).
To the solution (E-2), 43.8 g of silica sol (trade name Snowtex OXS, concentration 10 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −50 mV at pH = 7.0 may be added. The mixture was stirred to prepare a photocatalyst-containing coating liquid (F-2).
When the coating liquid (F-2) was allowed to stand at room temperature for 3 days, no abnormality was observed except that the cloudiness was slightly increased.

(2) Production and Evaluation of Photocatalyst-Containing Film-Supported Glass Mat Using the produced photocatalyst-containing coating liquid (F-2), the methylene blue adsorption characteristics of the photocatalyst-containing film-supported glass mat produced by the same method as in Example 1 were examined. As a result, the distribution coefficient K was 11.

Example 3
(1) Preparation of coating solution 1.80 g of aluminum nitrate nonahydrate was dissolved in 45.9 g of ethyl cellosolve, and 2.32 g of synthetic solution (C) was added and stirred well to prepare solution (D-3). Obtained.
40.8 g of the solution (D-3) was added to a mixed solvent of 326 g of ethyl cellosolve and 365 g of 1-propanol, and stirred well. Next, 7.32 g of distilled water, 60% by mass
Concentrated nitric acid 3.42g was added and stirred well, then 14.3g of titanium oxide sol (trade name PC-203, manufactured by Titanium Industry Co., Ltd.) was added and stirred well to obtain a solution (E-3).
To the solution (E-3), 43.8 g of silica sol (trade name Snowtex OXS, concentration 10 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −50 mV at pH = 7.0 may be added. The mixture was stirred to prepare a photocatalyst-containing coating liquid (F-3).
No abnormality was observed in the coating solution (F-3) which was allowed to stand at room temperature for 3 days, except that the cloudiness was slightly increased.

(2) Production and Evaluation of Photocatalyst-Containing Film-Supported Glass Mat Using the prepared photocatalyst-containing coating liquid (F-3), the methylene blue adsorption characteristics of the photocatalyst-containing film-supported glass mat produced by the same method as in Example 1 were examined. As a result, the distribution coefficient K was 3.

Example 4
(1) Preparation of coating solution 6.12 g of aluminum nitrate nonahydrate (purity 99%, manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 42.9 g of ethyl cellosolve, and then prepared in Synthesis Example 1. 55.2 g of the synthesis solution (C) was added and stirred well to obtain a solution (D-4). Subsequently, 1.46 g of the organic component solution (G) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.8 g of ethyl cellosolve, 20.82 g of the solution (D-4) described above, and pH = 7. Silica sol (trade name Snowtex IPA-ST, concentration 30% by mass, manufactured by Nissan Chemical Industries, Ltd.) 2.78 g in which Z potential characteristic at 0 is approximately −20 mV was mixed in the order of component gradient coating liquid (F− 4) was produced.
Even when the coating solution (F-4) was allowed to stand at room temperature for 3 days, almost no change was observed.

(2) Evaluation of gradient of component gradient film Using component gradient coating liquid (F-4) which was allowed to stand at room temperature for 3 days, a polyethylene terephthalate (PET) film with a weathering agent layer (trade name TP-60, Toray Industries, Inc. After the film was formed with a Meyer bar to a thickness of about 100 nm, the component gradient was examined by XPS. The component gradient between Si and Ti and the component gradient between Ti and organic were good. .
FIG. 1 is a graph showing the relationship between the sputtering time and the content of each element.

Example 5
(1) Preparation of coating solution 6.12 g of aluminum nitrate nonahydrate (purity 99%, manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 42.9 g of ethyl cellosolve, and then prepared in Synthesis Example 1. 55.2 g of the synthesis solution (C) was added and stirred well to obtain a solution (D-5). Subsequently, 1.46 g of the organic component solution (G) prepared in Synthesis Example 2, 47.08 g of methyl isobutyl ketone, 22.2 g of ethyl cellosolve, 20.82 g of the solution (D-5) described above, and pH = 7. Silica sol having a Z potential characteristic at 0 of about -50 mV (trade name Snowtex OXS, concentration 10% by mass, manufactured by Nissan Chemical Industries, Ltd.) 8.34 g in order and mixed with a component gradient coating liquid (F-5) Was made.
When the coating liquid (F-5) was allowed to stand at room temperature for 3 days, no abnormality was observed except that the yellowish color was slightly increased.

(2) Evaluation of gradient of component gradient film Using component gradient coating liquid (F-5) which was allowed to stand at room temperature for 3 days, a PET film with a weathering agent layer (trade name TP-60, manufactured by Toray Industries, Inc.) After forming a film with a Meyer bar to a thickness of about 100 nm, the component gradient was examined by XPS. Ti and organic component gradients were good, but Si and Ti were mixed somewhat homogeneously. It was.
FIG. 2 is a graph showing the relationship between the sputtering time and the content of each element.

Example 6
In 62.6 g of ethyl cellosolve, 1.34 g of aluminum nitrate nonahydrate (purity 99%, manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved, and then the synthetic solution (C) prepared in Synthesis Example 1 was 16. 1 g was added and stirred well to obtain a solution (D-6).
67 g of the solution (D-6) was added to a mixed solvent of 297 g of ethyl cellosolve and 357 g of 1-propanol and stirred well. Next, 51.8 g of distilled water and 2.78 g of 60% by mass concentrated nitric acid were added and stirred well, followed by anatase type photocatalytic titanium oxide sol (trade name PC-203, concentration 20% by mass, manufactured by Titanium Industry Co., Ltd.). 7.7 g was added and stirred well to obtain a solution (E-6).
16.0 g of silica sol (trade name Snowtex IPA-ST, concentration 30 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −20 mV at pH = 7.0 is added to the solution (E-6). The mixture was thoroughly stirred to prepare a photocatalyst-containing coating liquid (F-6).
When the coating liquid (F-6) was allowed to stand at room temperature for 3 days, no abnormality was observed except that the cloudiness was slightly increased.
By laminating the photocatalyst-containing coating solution (F-6) on the weathered PET with the component gradient film prepared in Example 4 so that the thickness of the film after drying with a Meyer bar is about 40 nm, A film was prepared and a SWM test was performed.
The degree of haze increase (ΔHz) after SWM 1500 h was 1.5%.

Example 7
(1) Preparation of coating solution In Example 1, silica sol (trade name Snowtex OXS, concentration: 10% by mass, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −50 mV at pH = 7.0. Instead, 4.39 g of tungsten oxide fine particles (manufactured by Junsei Chemical Co., Ltd.) having a Z potential characteristic of about −40 mV at pH = 7.0 and 39.4 g of distilled water were added and stirred well, and the photocatalyst-containing coating solution was added. A photocatalyst-containing coating solution (F-7) was prepared in the same manner as in Example 1 except that (F-7) was prepared.
The coating liquid (F-7) which was allowed to stand at room temperature for 3 days showed no particular abnormality except that the cloudiness was slightly increased.

(2) Production and Evaluation of Photocatalyst-Containing Film-Supporting Glass Mat Using the produced photocatalyst-containing coating liquid (F-7), the methylene blue adsorption characteristics of the photocatalyst-containing film-supporting glass mat produced by the same method as in Example 1 were examined. As a result, the distribution coefficient K was 14.

Example 8
(1) Preparation of coating solution In Example 1, silica sol (trade name Snowtex OXS, concentration: 10% by mass, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −50 mV at pH = 7.0. Instead, a solution obtained by diluting alumina sol (trade name: Alumina Sol-520, concentration 20% by mass, manufactured by Nissan Chemical Co., Ltd.) having a Z potential characteristic of about +35 mV at pH = 7.0 with pure water by 43 times was used. A photocatalyst-containing coating solution (F-8) was prepared in the same manner as in Example 1, except that .8 g was added and stirred well to prepare a photocatalyst-containing coating solution (F-8).
When the coating liquid (F-8) was allowed to stand at room temperature for 3 days, no abnormality was observed except that the cloudiness was slightly increased.

(2) Production and Evaluation of Photocatalyst-Containing Film-Supporting Glass Mat Using the produced photocatalyst-containing coating liquid (F-8), sunset yellow adsorption characteristics of the photocatalyst-containing film-supporting glass mat produced by the same method as in Example 1 As a result of the examination, the distribution coefficient K was 11.

Comparative Example 1
(1) Preparation of coating liquid 10.1 g of the synthetic liquid (C) prepared in Synthesis Example 1 was added to 19.9 g of ethyl cellosolve and stirred well to obtain a solution (d-1).
To a mixed solvent of 349 g of ethyl cellosolve and 364 g of 1-propanol, 16.8 g of the solution (d-1) was added and stirred well. Next, 7.56 g of distilled water and 3.36 g of 60 mass% concentrated nitric acid were added and stirred well, followed by anatase type photocatalytic titanium oxide sol (trade name PC-203, concentration 20 mass%, manufactured by Titanium Industry Co., Ltd.). 14.3 g was added and stirred well to obtain a solution (e-1).
To the solution (e-1), 43.8 g of silica sol (trade name Snowtex OXS, concentration 10 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −50 mV at pH = 7.0 may be added. The mixture was stirred to prepare a photocatalyst-containing coating liquid (f-1).
When the coating liquid (f-1) was allowed to stand at room temperature for 3 days, precipitation occurred.

Comparative Example 2
(1) Preparation of coating solution 1.46 g of organic component solution (G) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.8 g of ethyl cellosolve, and synthesis solution (C) prepared in Synthesis Example 1 20. 8 g and silica sol (trade name Snowtex IPA-ST, concentration 30 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −20 mV at pH = 7.0 were mixed in the order of 2.78 g. The component inclination coating liquid (f-2) was produced.
When the coating liquid (f-2) was allowed to stand at room temperature for 3 days, precipitation and gelation did not occur, but the yellowness was strong.

(2) Evaluation of gradient of component gradient film Using component gradient coating liquid (f-2) which was allowed to stand at room temperature for 3 days, a PET film with a weathering agent layer (trade name TP-60, manufactured by Toray Industries, Inc.) After forming a film with a Meyer bar to a thickness of about 100 nm, the component gradient was examined by XPS. The component gradient between Si and Ti and the component gradient between Ti and organic were good.
FIG. 3 is a graph showing the relationship between the sputtering time and the content of each element.

Comparative Example 3
1.46 g of the organic component solution (G) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 22.2 g of ethyl cellosolve, 20.8 g of the synthesis solution (C) prepared in Synthesis Example 1, and pH = 7.0 Silica sol (trade name Snowtex OXS, concentration 10% by mass, manufactured by Nissan Chemical Industries, Ltd.) 8.34 g in this order was mixed in the order of Z-potential property at about -50 mV and the component gradient coating liquid (f-3) was added. Produced.
When the coating liquid (f-3) was allowed to stand at room temperature for 3 days, gelation occurred.

Comparative Example 4
The photocatalyst-containing coating liquid (F-6) prepared in Example 6 is laminated on the weathered PET with a component gradient film prepared in Comparative Example 2 so that the film thickness after drying with a Meyer bar is about 40 nm. As a result, a photocatalytic film was prepared and a SWM test was performed.
The degree of haze increase (ΔHz) after SWM 1500 h was 25%.

Comparative Example 5
26.8 g of the synthesis solution (C) prepared in Synthesis Example 1 was added to 53.2 g of ethyl cellosolve, and the mixture was stirred well to obtain a solution (d-5).
67 g of the solution (d-5) was added to a mixed solvent of 297 g of ethyl cellosolve and 357 g of 1-propanol and stirred well. Next, 51.8 g of distilled water and 2.78 g of 60% by mass concentrated nitric acid were added and stirred well, followed by anatase type photocatalytic titanium oxide sol (trade name PC-203, concentration 20% by mass, manufactured by Titanium Industry Co., Ltd.). 7.7 g was added and stirred well to obtain a solution (e-5).
16.0 g of silica sol (trade name Snowtex IPA-ST, concentration 30 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −20 mV at pH = 7.0 is added to the solution (e-5). The mixture was thoroughly stirred to prepare a photocatalyst-containing coating solution (f-5).
When the coating liquid (f-5) was allowed to stand at room temperature for 3 days, precipitation did not occur but white turbidity was strong.
By laminating the above-mentioned photocatalyst-containing coating liquid (f-5) on the weathered PET with the component gradient film prepared in Comparative Example 2 so that the film thickness after drying with a Meyer bar is about 40 nm, the photocatalyst A film was prepared and a SWM test was performed.
The degree of haze increase (ΔHz) after SWM 1500 h was 30%.

Comparative Example 6
In Comparative Example 1, instead of silica sol (trade name Snowtex OXS, concentration 10 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −50 mV at pH = 7.0, pH = 7.0 4.38 g of tungsten oxide fine particles (manufactured by Junsei Chemical Co., Ltd.) having a Z potential characteristic of about −40 mV and 39.4 g of distilled water were added and stirred well to prepare a photocatalyst-containing coating liquid (f-6). Except for the above, a photocatalyst-containing coating solution (f-6) was produced in the same manner as in Comparative Example 1.
When the coating liquid (f-6) was allowed to stand at room temperature for 3 days, precipitation occurred.

Comparative Example 7
(1) Preparation of coating solution In Comparative Example 1, silica sol (trade name Snowtex OXS, concentration: 10 mass%, manufactured by Nissan Chemical Industries, Ltd.) having a Z potential characteristic of about −50 mV at pH = 7.0. Instead, a solution obtained by diluting alumina sol (trade name: Alumina Sol-520, concentration 20% by mass, manufactured by Nissan Chemical Co., Ltd.) having a Z potential characteristic of about +35 mV at pH = 7.0 with pure water by 43 times was used. A photocatalyst-containing coating solution (f-7) was prepared in the same manner as in Comparative Example 1, except that .8 g was added and stirred well to prepare a photocatalyst-containing coating solution (f-7).
When the coating liquid (f-7) was allowed to stand at room temperature for 3 days, precipitation and gelation did not occur, but white turbidity was strong.

(2) Production and Evaluation of Photocatalyst-Containing Film-Supported Glass Mat Using the produced photocatalyst-containing coating liquid (f-7), sunset yellow adsorption characteristics of the photocatalyst-containing film-supported glass mat produced by the same method as in Example 1 As a result of the examination, the distribution coefficient K was 7.

Example 9
By laminating the photocatalyst-containing coating solution (f-5) of Comparative Example 5 on the weathered PET with the component gradient film prepared in Example 4 so that the film thickness after drying with a Meyer bar is about 40 nm. A photocatalytic film was prepared and a SWM test was performed.
The degree of haze increase (ΔHz) after SWM 1500 h was 3.1%.
The results of Examples and Comparative Examples are shown in Table 3 and Table 4. Table 5 shows the contents of the composition of the photocatalyst liquid described in Table 4.

  The coating composition for forming an amorphous titanium oxide-containing composite film of the present invention maintains an amorphous state for a long period of time. For example, a coating agent for forming a photocatalytic film, a coating agent for forming a coating film having an automatic gradient, etc. Can be used as

6 is a graph showing the relationship between the sputtering time and the content of each element in the component gradient film formed in Example 4. 6 is a graph showing the relationship between the sputtering time and the content of each element in the component gradient film formed in Example 5. 10 is a graph showing the relationship between the sputtering time and the content of each element in the component gradient film formed in Comparative Example 2.

Claims (11)

Without containing the hydrolyzate of silane alkoxide, (A) General formula (I)
TiR ¹ _x (OR ² ) _4-x (I)
(In the formula, R ¹ represents an alkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group or acyl group, R ² represents an alkyl group having 1 to 6 carbon atoms, and x represents an integer of 0 to 2)
A coating composition for forming an amorphous titanium oxide-containing composite film, comprising: a hydrolysis condensate of titanium alkoxide represented by formula (B): aluminum nitrate; and (C) metal compound-based fine particles. The component (A) and the component (B) are represented by the following relational formula (II)
5 ≦ {aluminum atom in component (B) / [aluminum atom in component (B) + titanium atom in component (A)]} × 100 ≦ 60 (II)
The coating composition for forming an amorphous titanium oxide-containing composite film according to claim 1, which is contained in a ratio satisfying the above. The coating composition for forming an amorphous titanium oxide-containing composite film according to claim 1, wherein the metal compound-based fine particles of component (C) are fine particles having a photocatalytic function and / or silica fine particles. Further, (D) a coating film having a self-tilting property, which contains an organic component that can chemically bond with amorphous titanium oxide, and the content of the amorphous titanium oxide component is tilted from the surface toward the substrate. The coating composition for forming an amorphous titanium oxide-containing composite film according to any one of claims 1 to 3. (A) In an organic solvent, the general formula (I)
TiR ¹ _x (OR ² ) _4-x (I)
(In the formula, R ¹ represents an alkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group or acyl group, R ² represents an alkyl group having 1 to 6 carbon atoms, and x represents an integer of 0 to 2)
Hydrolyzing the titanium alkoxide represented by the step of preparing a liquid containing a hydrolyzed condensate of titanium alkoxide,
(B) a step of mixing the hydrolysis condensate-containing liquid of titanium alkoxide obtained in the step (a) and aluminum nitrate; and (c) a metal compound-based fine particle in the mixture obtained in the step (b). A step of containing,
The manufacturing method of the coating composition for amorphous | non-crystalline titanium oxide containing composite film formation of any one of Claims 1-4 characterized by the above - mentioned . An amorphous titanium oxide composite coating film obtained by using the coating composition for forming an amorphous titanium oxide-containing composite film according to any one of claims 1 to 4. An article comprising the amorphous titanium oxide composite coating film according to claim 6 on a substrate. The article according to claim 7, wherein the amorphous titanium oxide composite coating film is formed as an intermediate layer between an organic compound layer and an inorganic or metal compound layer. The article according to claim 7, wherein the amorphous titanium oxide composite coating film is on the outermost surface layer and exhibits a photocatalytic function. The article according to claim 7, wherein the amorphous titanium oxide composite coating film is on the outermost surface layer, exhibits a photocatalytic function, and exhibits solid acidity. The article according to claim 9 or 10, wherein an amorphous titanium oxide composite coating film having a self-gradient property is provided as an intermediate layer.

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