JP2010116504A - Highly transparent photocatalytic membrane and article including the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photocatalytic membrane formed on a base material by one-coating process, having excellent hydrophilicity, rarely demonstrating decomposition activity, thereby suppressing degradation of an organic base material and having high transparency. <P>SOLUTION: A coating agent, which includes a composite obtained by hydrolytic condensation of titanium alkoxide and an organic polymeric compound, is applied onto an organic base material only once to provide an amorphus titanium oxide film, wherein a content of a hydrolytic condensate of titanium alkoxide continuously varies from the surface toward the depth. A highly transparent photocatalytic membrane is obtained by heat treatment of the surface of the amorphus titanium oxide film in the presence of moisture at the temperature ≤100°C. The highly transparent photocatalytic film includes, in addition to a photocatalytic particle, a smaller metal oxide particle having a particular particle size range and a larger metal oxide particle having a particular particle size range at a predetermined ratio, and has a hubbly surface. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a highly transparent photocatalytic film and an article having the same. More specifically, the present invention is a photocatalytic film formed on a substrate by a one-coating method, having excellent hydrophilic performance but showing almost no decomposition activity, and having high transparency, and an organic substrate. The present invention relates to an article having the photocatalytic film thereon.

In general, when a photocatalyst is irradiated with light having energy greater than its band gap, electrons are excited in the conduction band and holes are generated in the valence band. The excited electrons reduce the surface oxygen to generate superoxide anions (· O ²⁻ ), and the holes oxidize the surface hydroxyl groups to generate hydroxyl radicals (· OH). It is known that the reactive active oxygen species exhibit a strong oxidative decomposition function and decompose organic substances adhering to the surface of the photocatalyst film with high efficiency.

  By applying such photocatalytic functions, for example, deodorization, antifouling, antibacterial, sterilization, and decomposition / removal of various substances that cause environmental pollution in wastewater and waste gas are being studied. Yes.

  Further, as another function of the photocatalyst, when the photocatalyst is photoexcited, for example, as disclosed in Patent Document 1, the surface of the photocatalyst film exhibits superhydrophilicity with a contact angle of 10 degrees or less with water. It is also known to do. Applying such a superhydrophilic function of photocatalysts, for example, for the purpose of imparting antifogging properties, dripproofing properties, antifouling properties, frostproofing properties, and snow sliding properties, highway soundproof walls, road reflectors, various types For reflectors, street lights, automobile body coats, side mirrors or window films, building materials including window glass, road signs, roadside signs, freezer / refrigerated showcases, various lenses and sensors, etc. The use of a photocatalytic film has been studied.

  Many photocatalysts have been known so far, and titanium oxide is one of the typical examples. In addition to amorphous amorphous type, there are three typical crystal systems of anatase type, rutile type, and brookite type. Titanium oxide exhibits photocatalytic activity in these three crystal systems. It is famous for expressing hydrophilicity. In particular, it is generally known that the anatase type exhibits the highest activity.

  The anatase-type titanium oxide is usually a hydrolysis condensate obtained by a sol-gel method using an organic titanium compound such as titanium alkoxide as a starting material, or a hydrated oxide of an inorganic titanium compound salt such as titanium tetrachloride or titanyl sulfate. It can be obtained by heat treatment from the obtained amorphous titanium oxide. However, since these usually require heat treatment at a high temperature of 400 ° C. or higher, it is inevitable that the cost is high, and it is difficult to form a film on a substrate having poor heat resistance. It is accompanied.

  Therefore, various methods for obtaining a highly active anatase-type titanium oxide at a relatively low temperature have been tried and disclosed.

  For example, when a titanium oxide film is formed on a substrate by a physical film-forming method such as sputtering or vacuum deposition, by introducing a lot of hydroxyl groups into amorphous titanium oxide by introducing water vapor, atoms in the titanium oxide skeleton There has been proposed a method of increasing the mobility of the metal and facilitating the subsequent crystallization by heat treatment (see, for example, Patent Document 2). According to this, it is possible to lower the crystallization temperature to about 200 ° C.

  Further, from a solution containing silicon alkoxide and a hydrolyzable titanium compound, a gel film containing a composite metal oxide or hydroxide in which a titanium compound and silicon alkoxide are blended at a predetermined molar ratio is formed, A method for precipitating titania microcrystals belonging to anatase having a crystal diameter of about several tens to 100 nm by contacting with hot water of 100 ° C. or lower is disclosed (for example, see Patent Document 3).

  Certainly, according to the above-described method, it is considered that an amorphous titanium oxide can be directly formed on a material having low heat resistance such as a plastic substrate, and then an anatase-type titanium oxide can be formed through a low-temperature heat treatment step. . However, the anatase-type titanium oxide obtained by these methods, as clearly shown in that publication, exhibits high organic matter decomposition activity in addition to the expression of photoexcited superhydrophilicity as well as general anatase-type titanium oxide, When directly formed on a plastic substrate, the substrate is eroded in a short period of time due to its high organic matter decomposition activity, and the physical properties of the substrate deteriorate or the photocatalytic function deteriorates due to the removal of the photocatalyst film. Etc. are easily guessed. For this reason, each of the above methods requires a separate active blocking layer together with the anatase-type titanium oxide film, and can be cured at room temperature, for example, made by dispersing anatase-type titanium oxide fine particles in an inorganic binder. Compared with the method of applying the photocatalyst coating agent, no clear superiority was found.

  On the other hand, as a method for directly applying anatase-type titanium oxide onto an organic substrate such as plastic, for example, the surface energy of anatase-type titanium oxide fine particles is reduced by modifying the anatase-type titanium oxide surface with a fluorine-based silane coupling agent. A self-gradient photocatalytic coating agent that floats (segregates) on the surface of the coating film by weakening the interaction with the binder component is known (see Patent Document 4). In addition, a photocatalyst material having a mask melon shape has been proposed by coating the surface of titanium oxide with an inert inorganic material as a photocatalyst and providing numerous pores (see Patent Document 5).

  Since these can avoid that anatase type titanium oxide contacts a organic base material directly, it is thought that it can apply | coat to an organic base material directly. However, all of these require complex surface treatment to prevent the influence of the high oxidizing power of anatase-type titanium oxide on the substrate, and moreover, they are thick due to surface segregation of titanium oxide. There are many restrictions, such as the necessity of micron order and the fact that titanium oxide particles themselves can only be produced with a diameter of several microns.

  By the way, there is a method of providing a photocatalyst layer on the base material as a method for giving an organic base material typified by a plastic base material high hydrophilic performance and developing antifouling property. Therefore, a layer for protecting the organic base material has to be provided from the oxidative degradability of the reactive active species generated from the above, and thus a two-layer coating method is required, which has been a factor of high cost.

  The inventors of the present invention have made extensive studies in order to deal with such problems. First, the present invention exhibits excellent hydrophilic performance with a one-coat method on an organic base material, but suppresses deterioration of the base material. A technology for forming a photocatalyst layer that can be used was found and a patent was filed (Japanese Patent Application No. 2008-024479).

  This technology shows sufficient photoexcited superhydrophilicity under solar light source irradiation, but the antihydrophobic, dripproof, and antifogging properties brought about by this superhydrophilic property are the photoexcited type, so the time until functional development is achieved. It has been pointed out that it varies greatly depending on how sunlight hits. In particular, in anti-fogging properties, in some cases, it may be desired to develop excellent superhydrophilic properties in a short period of time, and lowering of the initial contact angle and improvement of the hydrophilization rate may be required more than ever. In addition, the photocatalytic film used for window materials, automobile side mirrors, curve mirrors, reflectors, and the like is required to have high transparency in addition to the hydrophilic performance.

International Patent Publication No. 96/29375 Pamphlet JP 2000-345320 A JP 2002-97013 A JP 2005-131640 A Japanese Patent No. 3484470

  Under such circumstances, the present invention has an excellent hydrophilic performance formed by a one-coating method on a substrate, which is suitable for a field where high hydrophilic performance and transparency are required. Since the activity is hardly exhibited, it is an object to provide a photocatalyst film having high transparency and an article having the photocatalyst film on the base material, which can suppress deterioration of the organic base material.

As a result of intensive studies to achieve the above object, the present inventors have obtained the following knowledge.
On the organic base material, a specific coating agent is applied by a one-coat method to form an amorphous titanium oxide film having a component gradient structure, and the surface of the amorphous titanium oxide film is subjected to specific conditions. By photocatalyzing or by photocatalytic treatment, a supercatalytic property is exhibited, but a photocatalytic film capable of effectively suppressing deterioration of the organic base material can be obtained while exhibiting almost no decomposition activity on organic substances. I found out.

In addition to the photocatalyst particles, the photocatalyst film includes irregularities on the surface thereof by containing metal oxide small particles having a specific particle size range and metal oxide large particles having a specific particle size range at a predetermined ratio. Was found to improve the hydrophilic performance and increase the transparency.
The present invention has been completed based on such findings.

That is, the present invention
(1) A hydrolysis condensate of titanium alkoxide provided by applying a coating agent containing a complex formed by hydrolysis and condensation of titanium alkoxide and an organic polymer compound only once on an organic base material. This is a photocatalytic film obtained by exposing the surface of an amorphous titanium oxide film in which the content ratio of the aqueous solution continuously changes from the surface to the depth direction to a temperature of 100 ° C. or lower in the presence of water vapor. In addition to the photocatalyst particles, (a) metal oxide particles A having an average particle size of less than 40 nm and (b) metal oxide particles B having an average particle size of 40 nm or more and less than 90 nm or metal oxide having an average particle size of 90 nm or more and less than 150 nm Product particles C or metal oxide particles D having an average particle size of 150 nm or more and less than 200 nm, and the mixing ratio thereof is expressed by the following relational expressions (1) to (3) on a mass basis:
80/20 ≦ A / B ≦ 45/55 (1)
97/3 ≦ A / C ≦ 70/30 (2)
97/3 ≦ A / D ≦ 88/12 (3)
And a highly transparent photocatalytic film characterized by having irregularities on the surface,
(2) Item (1) above, which is a photocatalytic film obtained by heat-treating the surface of an amorphous titanium oxide film coated on an organic base material at a temperature of 100 ° C. or less in the presence of moisture. A highly transparent photocatalytic film as described in
(3) The highly transparent photocatalyst film according to (1) or (2) above, wherein the haze value of the photocatalyst film itself measured in accordance with JIS K 7361 is less than 0.6%,
(4) The high transparency according to any one of (1) to (3) above, wherein the metal oxide particles A to D are at least one selected from silica, titania, zirconia, alumina, and magnesia. Photocatalytic membrane,
(5) The highly transparent photocatalyst film according to the above (4), wherein the metal oxide particles A to D are silica-based particles,
(6) In addition to the photocatalyst particles, as compared with a photocatalyst film containing only the metal oxide particles A, the hydrophilization rate is improved by 2 times or more, and any one of the above items (1) to (5) Highly transparent photocatalytic membrane,
(7) An article having the highly transparent photocatalyst film according to any one of (1) to (6) above on the surface of an organic base material, and (8) a highly transparent photocatalyst The article according to (7) above, further having a functional film on the surface of the film,
Is to provide.

  According to the present invention, it is formed by a one-coat method on an organic substrate suitable for fields requiring high hydrophilic performance and transparency, such as window materials, automobile side mirrors, curve mirrors, reflectors, and the like. Although it has excellent hydrophilic performance but exhibits almost no decomposition activity, it can suppress deterioration of the organic base material, and has a highly transparent photocatalytic film, and an article having the photocatalytic film on the organic base material Can be provided.

First, the highly transparent photocatalytic film of the present invention will be described.
The highly transparent photocatalytic film of the present invention was provided by applying a coating agent containing a complex formed by hydrolysis and condensation of a titanium alkoxide and an organic polymer compound only once on an organic base material. The surface of the amorphous titanium oxide film in which the content of the hydrolysis condensate of titanium alkoxide continuously changes from the surface in the depth direction is exposed to a temperature of 100 ° C. or less in the presence of water vapor. It is the obtained photocatalyst film.

[Properties of photocatalyst film]
The photocatalytic film of the present invention is an amorphous titanium oxide having a component gradient structure in which the content of the titanium alkoxide hydrolysis condensate provided on the organic base material continuously changes from the surface in the depth direction. The film surface is exposed to a temperature of 100 ° C. or lower in the presence of water vapor and photocatalyzed, or is heat-treated at a temperature of 100 ° C. or lower in the presence of moisture to obtain a photocatalyst. It has a characteristic that it exhibits super hydrophilicity but exhibits almost no decomposition activity on organic substances.

  The photocatalyst film of the present invention thus obtained preferably contains photo semiconductor particles, and the photo semiconductor particles preferably contain crystalline titanium oxide.

  The crystalline titanium oxide may be any of anatase type, rutile type, brookite type crystalline titanium oxide, or the above crystalline titanium oxide containing crystal defects and crystal distortion, A combination of two or more of these crystalline titanium oxides may be used.

  Further, the ratio of the crystalline titanium oxide having a crystal diameter in the range of 1 to 10 nm in the total crystalline titanium oxide contained in the photocatalytic film of the present invention is preferably 90% or more, and 100%. It is more preferable.

  In the present invention, the crystal diameter means the maximum length of lattice fringes of crystal grains when a cross section of crystalline titanium oxide is observed with a transmission electron microscope, and the crystal diameter is in the range of 1 to 10 nm. The content ratio of a certain crystalline titanium oxide can be obtained by calculating the ratio of the number of crystals having a crystal diameter in the range of 1 to 10 nm with respect to the total number of crystals when the cross section of the photocatalyst film is observed with a transmission electron microscope. .

  The photocatalyst film of the present invention preferably has at least 5 crystal grains, preferably 10 or more, by observing a cross section of the photocatalyst film in a 50 nm × 50 nm range with a transmission electron microscope. Is more preferable. When the number of crystal grains in the observation range is 5 or more, it is possible to obtain a photocatalyst film having a superhydrophilicity imparting function but having suppressed decomposition activity. The photocatalyst film of the present invention is preferably formed by dispersing crystalline titanium oxide in amorphous titanium oxide. In this case, for example, it is preferable that the crystallized titanium particles are scattered in islands in the amorphous titanium oxide sea when observed with a transmission electron microscope.

  The photocatalyst film of the present invention preferably has a limit contact angle with water of less than 20 degrees at the time of sunlight irradiation, more preferably 10 degrees or less.

In the photocatalyst film of the present invention, the degradation rate of methylene blue when irradiated with artificial sunlight of 3 mW / cm ² is 0.1 or less in terms of the rate of decrease in absorbance (decomposition activity) ΔABS / min at the maximum absorption wavelength of the applied methylene blue. Is preferably 0.05 or less, more preferably 0.01 or less, and even more preferably 0.0015 or less.

  The contact angle with water and the decomposition rate of methylene blue can be controlled, for example, by adjusting the crystal diameter and content ratio of crystalline titanium oxide.

  Furthermore, the photocatalyst film of the present invention has irregularities on the surface, exhibits excellent hydrophilic performance, has low reflectivity, and has high transparency.

  According to Wenzel's law, it is known that the wettability of the coating film is emphasized and the hydrophilic performance is improved by imparting a certain degree of unevenness to the coating film surface. The inventors of the present invention have improved the hydrophilic performance of the photocatalyst film effectively, and have conducted research on the unevenness that effectively lowers the reflectance and increases the transparency, thereby completing the present invention. .

That is, the photocatalyst film of the present invention includes, in addition to the photocatalyst particles, (a) metal oxide particles A having an average particle size of less than 40 nm and (b) metal oxide particles B having an average particle size of 40 nm or more and less than 90 nm or an average particle size. Including metal oxide particles C of 90 nm or more and less than 150 nm or metal oxide particles D having an average particle diameter of 150 nm or more and less than 200 nm, and the mixing ratio thereof is represented by the following relational expressions (1) to (3) on a mass basis:
80/20 ≦ A / B ≦ 45/55 (1)
97/3 ≦ A / C ≦ 70/30 (2)
97/3 ≦ A / D ≦ 88/12 (3)
And the surface has irregularities.

  Note that “80/20 ≦ A / B ≦ 45/55” in the relational expression (1) indicates that the mass ratio of A and B is in the range of 80:20 to 45:55. The same applies to the other relational expressions (2) and (3).

The ratio of the mass reference between the metal oxide particles A and the metal oxide particles B, C, or D satisfies the above relational expressions (1), (2), and (3), respectively. The haze value measured according to JIS K 7361 of the highly transparent photocatalyst film itself can be made less than 0.6%, and compared with the photocatalyst film containing only the metal oxide particles A in addition to the photocatalyst particles. The hydrophilization rate can be improved by 2 times or more.
The haze value and the hydrophilization rate of the photocatalyst film are values measured by the following method.

<Hydrophilic speed of photocatalyst film>
UV / visible light region of a sample that was formed on a colorless transparent acrylic plate (Mitsubishi Rayon Co., Ltd., “Acrylite L”) with a thickness of 100 nm and made sufficiently hydrophobic in the dark. The artificial solar light source (“XC-100BSS” manufactured by Celic) whose emission spectrum is similar to that of sunlight is used to irradiate pseudo-sunlight, and then a contact angle meter (“G-1-1000 manufactured by Elma Sales Co., Ltd.). )), The change with time of the contact angle with pure water was followed. The hydrophilization speed is obtained by plotting the reciprocal of the water contact angle value against the light irradiation time (min) and taking the slope of the linear approximation line.

<Haze value of photocatalyst film>
A photocatalyst film having a thickness of 100 nm is formed on a 2 mm-thick colorless transparent acrylic plate (described above), and a haze value is obtained according to JIS K 7361 using a Nippon Denshoku haze meter “NDH-2000”. . The haze value of the photocatalyst film itself was determined by subtracting the haze value of the acrylic plate alone from the haze value of the colorless and transparent acrylic plate described above on which the photocatalyst film was formed.

  Examples of the metal oxide particles A to D used in the present invention include silica, titania, zirconia, alumina, and magnesia. These may be used singly or in combination of two or more. Among them, the silica-based fine particles are used in view of the effect of reducing the haze value of the photocatalyst film and improving the hydrophilization rate. To preferred.

Further, the total amount of the metal oxide particles A and B or C or D contained in the photocatalyst film of the present invention is 10 to 10 from the viewpoint of the haze value reduction effect and the hydrophilization speed improvement effect of the photocatalyst film. The content is preferably 80% by mass, and more preferably 25 to 75% by mass.
In addition, the average particle diameter of each said metal oxide particle is a value measured by a laser scattering diffraction method.

[Production of photocatalytic film]
As described above, the photocatalyst film of the present invention contains crystalline titanium oxide which is a photo semiconductor particle, and has a specific particle size range in addition to the photocatalyst particle, in order to give unevenness to the surface. Product particles A and metal oxide particles B, C, or D. Further, titanium alkoxide is hydrolyzed and condensed with the organic polymer compound to form a complex whose content continuously changes from the surface in the depth direction.

  Specific examples of the titanium alkoxide include titanium tetraalkoxide described below, and specific examples of the organic compound include an organic polymer compound having a hydrolyzable metal-containing group described below.

  The photocatalytic film of the present invention preferably further comprises at least one metal compound selected from inorganic metal salts, organic metal salts, and alkoxides of metals other than titanium and silicon. Specific examples of the metal compound are as described later, and aluminum nitrate is particularly preferable.

  The photocatalytic film of the present invention is obtained by subjecting an amorphous titanium oxide film to heat treatment at a temperature of 100 ° C. or lower in the presence of water vapor or by exposure to a temperature of 100 ° C. or lower in the presence of moisture. Manufactured by. In this case, it is preferable to produce the photocatalyst in an environment having a temperature of 100 ° C. or lower and a relative humidity of 5% or higher.

Further, in the present invention, in the above environment, it is preferable to produce in the presence of light including ultraviolet light while further having a wavelength in an arbitrary region selected from a wavelength region of 250 to 1200 nm. One suitable manufacturing condition is that the temperature is 30 to 60 ° C. and the relative humidity is 50 to 80% while irradiating under an illuminance of 5 to 400 W / m ² .

The light having an arbitrary region selected from the wavelength region of 250 to 1200 nm and including the ultraviolet light preferably includes at least light having a wavelength of 250 to 260 nm, 290 to 315 nm, and 350 to 1200 nm. It is further preferable to irradiate under the condition of irradiance of 200 to 400 W / m ² .

  In the present invention, it is preferable to spray water at least once. There are no particular restrictions on the equipment and equipment used in the present invention, but typically, various equipment that can provide a constant temperature and humidity environment, carbon arc type sunshine weather meter, xenon weather meter, metering weather meter, dew panel A weather meter can be exemplified.

  In addition, the photocatalyst film of the present invention can be similarly produced by exposure in an outdoor environment in which the same conditions as described above are obtained.

  The photocatalyst film of the present invention comprises (A) a titania sol obtained by hydrolytic condensation of titanium alkoxide, and (B) a metal-containing group that can be bonded to titanium oxide by hydrolysis in the molecule (referred to as a hydrolyzable metal-containing group). And (C) a coating agent containing metal oxide particles for forming irregularities, and this film is produced by photocatalysis under the production conditions described above. The

  In the preparation of titania sol obtained by hydrolytic condensation of titanium tetraalkoxide as component (A), titanium tetraalkoxide having about 1 to 4 carbon atoms of the alkoxyl group is used as the raw material titanium tetraalkoxide. In this titanium tetraalkoxide, the four alkoxyl groups may be the same or different, but the same one is preferably used from the viewpoint of availability. Examples of the titanium tetraalkoxide include titanium tetramethoxide, titanium tetraethoxide, titanium tetra-n-propoxide, titanium tetraisopropoxide, titanium tetra-n-butoxide, titanium tetraisobutoxide, titanium tetra-sec-butoxide and An example is titanium tetra-tert-butoxide. These may be used individually by 1 type and may be used in combination of 2 or more type.

  The titanium tetraalkoxide is hydrolyzed and condensed to prepare a titania sol solution. This hydrolysis-condensation reaction of the titanium tetraalkoxide is preferably carried out by using water having an alcohol having an ether-based oxygen having 3 or more carbon atoms as a solvent and allowing water to act on the titanium tetraalkoxide.

  Examples of the alcohols having ether oxygen having 3 or more carbon atoms include solvents having an interaction with titanium tetraalkoxide, such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether. Cellosolve solvents such as ethylene glycol mono-t-butyl ether, 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, etc. It can be mentioned. Among these, a cellosolve solvent having a strong interaction with titanium tetraalkoxide is particularly preferable. These solvents may be used singly or in combination of two or more.

  By using a solvent having such an interaction with titanium tetraalkoxide as a solvent, the titania sol solution obtained by the hydrolysis-condensation reaction of titanium tetraalkoxide can be stabilized, and the condensation reaction can proceed. However, gelation and particle formation are less likely to occur.

  The hydrolysis-condensation reaction of titanium tetraalkoxide is about 4 to 20 times mol, preferably 5 to 12 times mol of the above alcohols and about 0.5 times mol to less than 4 times mol of titanium tetraalkoxide, preferably 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 or 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.

  The organic polymer compound having a hydrolyzable metal-containing group as the component (B) includes, for example, (x) an ethylenically unsaturated monomer having a hydrolyzable metal-containing group, and (y) an ethylenic compound not containing a metal. It can be obtained by copolymerizing unsaturated monomers.

  Examples of the ethylenically unsaturated monomer having a hydrolyzable metal-containing group as the component (B) (x) include those represented by the general formula (4)

（式中、Ｒ^１は水素原子またはメチル基、Ａはアルキレン基、好ましくは炭素数１〜４のアルキレン基、Ｒ^２は加水分解性基または非加水分解性基であるが、その中の少なくとも１つは加水分解により、（Ａ）成分と化学結合しうる加水分解性基であることが必要であり、また、Ｒ^２が複数の場合には、各Ｒ^２はたがいに同一であってもよいし、異なっていてもよく、Ｍ^１はケイ素、チタン、ジルコニウム、インジウム、スズ、アルミニウムなどの金属原子、ｋは金属原子Ｍ^１の価数である。）
で表されるものを挙げることができる。

Wherein R ¹ is a hydrogen atom or a methyl group, A is an alkylene group, preferably an alkylene group having 1 to 4 carbon atoms, and R ² is a hydrolyzable group or a non-hydrolyzable group, the first is hydrolysis, it is required to be a hydrolyzable group capable of binding the component (a) and the chemical, and when R ² is plural, each R ² is also a mutually identical M ¹ is a metal atom such as silicon, titanium, zirconium, indium, tin, and aluminum, and k is the valence of the metal atom M ¹ .
Can be mentioned.

In the general formula (4), examples of the hydrolyzable group that can chemically bond to the component (A) by hydrolysis of R ² include halogen atoms such as alkoxyl groups, isocyanate groups, and chlorine atoms, oxyhalogen groups, An acetylacetonate group, a hydroxyl group, etc. are mentioned, On the other hand, as a non-hydrolyzable group which does not chemically bond with (A) component, a lower alkyl group etc. are mentioned preferably, for example.

Examples of the metal-containing group represented by -M ¹ R ² _k-1 in the general formula (4) include a trimethoxysilyl group, a triethoxysilyl group, a tri-n-propoxysilyl group, a triisopropoxysilyl group, Tri-n-butoxysilyl group, triisobutoxysilyl group, tri-sec-butoxysilyl group, tri-tert-butoxysilyl group, trichlorosilyl group, dimethylmethoxysilyl group, methyldimethoxysilyl group, dimethylchlorosilyl group, methyl Dichlorosilyl group, triisocyanatosilyl group, methyldiisocyanatosilyl group, trimethoxytitanium group, triethoxytitanium group, tri-n-propoxytitanium group, triisopropoxytitanium group, tri-n-butoxytitanium group, Triisobutoxy titanium group, tri-s ec-butoxytitanium group, tri-tert-butoxytitanium group, trichlorotitanium group, trimethoxyzirconium group, triethoxyzirconium group, tri-n-propoxyzirconium group, triisopropoxyzirconium group, tri-n-butoxy Zirconium group, triisobutoxyzirconium group, tri-sec-butoxyzirconium group, tri-tert-butoxyzirconium group, trichlorozirconium group, or even dimethoxyaluminum group, diethoxyaluminum group, di-n-propoxyaluminum group, Diisopropoxyaluminum group, di-n-butoxyaluminum group, diisobutoxyaluminum group, di-sec-butoxyaluminum group, di-tert-butoxyaluminum group, Such as chloro aluminum group.

  One type of the ethylenically unsaturated monomer of component (x) may be used, or two or more types may be used in combination.

  On the other hand, examples of the ethylenically unsaturated monomer not containing a metal as the component (y) include, for example, the general formula (5).

（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（５−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 formula (5-a)

（式中、Ｒ^３は前記と同じであり、Ｒ^４は炭化水素基を示す。）
で表されるエチレン性不飽和単量体、あるいは上記一般式（５−ａ）で表されるエチレン性不飽和単量体と、必要に応じて添加される密着性向上剤としての一般式（５−ｂ）

(In the formula, R ³ is the same as described above, and R ⁴ represents a hydrocarbon group.)
Or an ethylenically unsaturated monomer represented by the above general formula (5-a), and a general formula ( 5-b)

（式中、Ｒ^５は水素原子またはメチル基、Ｒ^６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との混合物を挙げることができる。

(In the formula, R ⁵ represents a hydrogen atom or a methyl group, and R ⁶ represents an epoxy group, a halogen atom or a hydrocarbon group having an ether bond.)
And a mixture with an ethylenically unsaturated monomer represented by the formula:

In the ethylenically unsaturated monomer represented by the general formula (5-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 ethylenically unsaturated monomer represented by the general formula (5-a) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl ( Examples include meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, and benzyl (meth) acrylate. These may be used alone or in combination of two or more.

In the ethylenically unsaturated monomer represented by the general formula (5-b), the epoxy group represented by R ⁶ , the halogen atom, or the hydrocarbon group having an ether bond is a linear chain having 1 to 10 carbon atoms. Preferred examples include a straight or branched alkyl group, a cycloalkyl group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, and an aralkyl group having 7 to 10 carbon atoms. The halogen atom for the substituent is preferably a chlorine atom or a bromine atom. Specific examples of the hydrocarbon group include the same groups as those exemplified in the description of R ⁴ in the general formula (5-a).

  Examples of the ethylenically unsaturated monomer represented by the general formula (5-b) include glycidyl (meth) acrylate, 3-glycidoxypropyl (meth) acrylate, and 2- (3,4-epoxycyclohexyl). ) Ethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-bromoethyl (meth) acrylate and the like can be preferably exemplified.

  In addition to these, the ethylenically unsaturated monomer represented by the general formula (5) 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.

  When the ethylenically unsaturated monomer represented by the general formula (5-a) and the ethylenically unsaturated monomer represented by the general formula (5-b) are used in combination, the former ethylenic monomer It is preferable to use the latter ethylenically unsaturated monomer in a proportion of 1 to 100 mol% with respect to the unsaturated monomer.

  In the presence of a radical polymerization initiator, an ethylenically unsaturated monomer having a hydrolyzable metal-containing group as the component (x) and an ethylenically unsaturated monomer not containing a metal as the component (y) By copolymerization, an organic polymer compound having a hydrolyzable metal-containing group as component (B) is obtained.

  On the other hand, as described above, the metal oxide particles for forming irregularities as the component (C) are (a) metal oxide particles A having an average particle size of less than 40 nm, and (b) average particle size of 40 nm or more. The metal oxide particles B having an average particle diameter of 90 nm or more and less than 150 nm or the metal oxide particles D having an average particle diameter of 150 nm or more and less than 200 nm are used.

  The use ratio of the metal oxide particles A and the metal oxide particles B, C, or D is as shown by the relational expressions (1) to (3).

  As the metal oxide particles A to D, at least one selected from silica, titania, zirconia, alumina, and magnesia is preferably used, and among these, silica-based fine particles are preferable. As the silica-based fine particles, colloidal silica is preferable.

  In the present invention, the titania sol solution (A) obtained as described above and the organic polymer compound having a hydrolyzable metal-containing group (B) component are dissolved in an appropriate polar solvent. A coating solution can be obtained by adjusting the mixed solution of the solution thus prepared and the metal oxide particles for forming irregularities as the component (C) to a viscosity suitable for coating. At this time, if necessary, water and / or an acidic catalyst may be added to the coating solution.

  By including the component (C) in the coating liquid, irregularities are imparted to the surface of the resulting photocatalyst film, and the hydrophilic performance and transparency of the photocatalyst film are improved.

  Furthermore, the coating agent used for forming an amorphous titanium oxide film having a component gradient structure includes an inorganic metal salt, an organic metal salt, and a metal other than titanium and silicon as a substance that regulates crystal formation of amorphous titanium oxide. At least one metal-based compound selected from the alkoxides can be contained. Specifically, aluminum nitrate, aluminum acetate, aluminum sulfate, aluminum chloride, each salt such as zirconium nitrate, zirconium acetate, zirconium sulfate, zirconium chloride, and hydrates of these inorganic salts, aluminum triacetylacetonate, etc. And metal alkoxides such as tetra-n-propoxyzirconium, tetraethoxysilane, and phenyltrimethoxysilane, and hydrolysates or condensates of these compounds. Of these, aluminum nitrate and hydrates thereof are particularly preferred. The said crystal formation regulator may be used individually by 1 type, and may be used in combination of 2 or more type.

  As described above, by including the crystal formation adjusting substance in the coating agent, it is possible to adjust the microcrystal formation behavior (for example, crystal formation rate, crystal growth rate, etc.) of titanium oxide in the formed photocatalytic film. . In addition, it is possible to control the time until the onset of super hydrophilicity according to the environment used and the required performance, and to contribute to the adjustment of the stability of the film, such as suppressing the occurrence of cracks due to shrinkage. You can also.

  In the present invention, the coating liquid obtained as described above on the organic base material has a dry coating thickness of usually 0.01 to 1 μm, preferably 0.03 to 0.3 μm. The coating is performed by a known means such as a dip coating method, a spin coating method, a spray coating method, a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, and a solvent. It is preferable to volatilize and 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, 6- Substrates made of polyamide resins such as nylon and 6,6-nylon, polyvinyl chloride resins, polycarbonate resins, polyphenylene sulfide resins, polyphenylene ether resins, polyimide resins, cellulose resins such as cellulose acetate, etc. Can be mentioned.

  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 to the component gradient film 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 the present invention, as the organic substrate, an organic coating film is formed on the surface of a substrate made of a material other than an organic material, for example, a metal material, glass, a ceramic material, or other various inorganic or metal materials. The thing which has is included.

  In the present invention, the coating film formed in this way is usually subjected to a heat treatment at a temperature of 0 to 200 ° C., preferably 15 to 150 ° C., thereby forming a component gradient structure with irregularities on the surface. An amorphous titanium oxide film is formed.

The component gradient structure is confirmed, for example, by performing sputtering on the obtained film surface and measuring the content of carbon atoms and titanium atoms on the film surface over time by X-ray photoelectron spectroscopy or the like. be able to.
Next, the article of the present invention will be described.

[Goods]
The article of the present invention is characterized by having the highly transparent photocatalytic film of the present invention on the surface of an organic base material.
Furthermore, the article of the present invention can further be provided with a functional film having a thickness of 500 nm or less on the surface of the photocatalyst film as long as the function of the photocatalyst film of the present invention is not impaired.

  Examples of the function of the functional film include hydrophilicity retention in a dark place, conductivity, chargeability, hard coat property, reflection characteristic control, refractive index control, and the like. In addition, specific constituent components of the functional film include metal oxide compounds such as silica, alumina, zirconia, ITO, and zinc oxide. In particular, it is preferable to contain silica for the purpose of maintaining hydrophilicity at night when sunlight is not applied.

  In the article of the present invention, examples of the organic base material on which the highly transparent photocatalytic film is formed include the same organic base materials as exemplified above, and are provided on the same as described above. In order to improve the adhesion to the photocatalyst film, a surface treatment can be performed by an oxidation method, an unevenness method, or the like.

  As articles of the present invention, sound barriers for highways, road reflectors, various reflectors, street lamps, body coats and side mirrors for automobiles including automobiles, films for windows, building materials including window glass, road signs, There are roadside signs, freezer / refrigerated showcases, various lenses and sensors.

  Moreover, an agricultural film can also be mentioned as an article of the present invention. In recent years, agricultural films have been actively used for house cultivation and tunnel cultivation, and in such cultivation, when agricultural films are spread and used, they prevent fogging caused by water droplet adhesion. Therefore, after spreading, a drip-proof agent (anti-fogging agent) was sprayed on the inner surface, but this drip-proof agent (anti-fogging agent) lost the drip-proof effect in a short period of time. On the other hand, the agricultural film having the photocatalytic film of the present invention on the surface can maintain hydrophilicity for a long period of time, so that it is possible to continue the farm work without requiring recoating.

  As described above, the article of the present invention has a superhydrophilicity imparting function, but has a photocatalyst film with suppressed decomposition activity, so that the surface of the article can be made hydrophilic without eroding the organic base material. It becomes possible to become.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
In addition, the performance of the photocatalyst film formed in each example was measured according to the following method.

(1) Hydrophilization speed The hydrophilization speed was measured according to the method described in the main text of the specification, and the value of the photocatalyst film of Comparative Example 1 was taken as 1 and indicated as an index.
(2) Haze value The haze value was measured according to the method described in the specification text. The lower the haze value, the better the transparency.

Synthesis Example 1 Preparation 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 added dropwise with stirring, and the solution (A ) 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). Thereafter, the solution (B) was stirred at 30 ° C. for 4 hours to obtain a hydrolytic condensation liquid (C) of titanium alkoxide.

Synthesis Example 2 Preparation of Organic Polymer Component Solution In a 2 L separable flask, 704 g of methyl isobutyl ketone, 332 g of methyl methacrylate and 42.0 g of methacryloxypropyltrimethoxysilane were added under a nitrogen atmosphere, and the temperature was raised to 60 ° C. To this mixed solution, 103 g of methyl isobutyl ketone in which 3.2 g of azobisisobutyronitrile was dissolved was dropped to start the polymerization reaction, and stirred for 30 hours to obtain an organic polymer component solution (D).

Example 1
1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 8.57 g of ethyl cellosolve, and then the hydrolytic condensate (C) of titanium alkoxide prepared in Synthesis Example 1 was dissolved in 11 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Product name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.09 g, Colloidal silica B (Product name: IPA-ST-L (average particle size 50 nm), Nissan Chemical Industries, Ltd.) Made in order of 0.70 g, and then stirred in a warm bath at 33 ° C. for 24 hours, and a gradient film coating solution of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component ( H). At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.

  After that, the coating liquid (H) is applied to a 2 mm-thick colorless and transparent acrylic plate (Mitsubishi Rayon, “Acrylite L”) with a wet thickness of about 10 μm using a spin coater so that the dry thickness becomes 100 nm. It was applied to. Next, this coating film was photocatalyzed for 15 hours in a constant temperature and humidity chamber at 85 ° C. and 95% RH.

  The haze value of this photocatalyst film itself was 0.30%, and the hydrophilization rate was 2.19 times that of Comparative Example 1. In addition, using an XPS apparatus “PHI-5600” [manufactured by ULVAC-PHI Co., Ltd.], argon sputtering (4 kV) was applied at intervals of 3 minutes to scrape the film, and the content of carbon atoms and metal atoms on the film surface was determined by X-ray photoelectron. As a result of measurement by spectroscopic method and investigation of the gradient, it was confirmed that it has a component gradient structure in which the content of metal atoms continuously decreases in the depth direction from the surface.

Example 2
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Product name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 1.39 g, colloidal silica B (product name: IPA-ST-L (average particle size 50 nm), Nissan Chemical Industries, Ltd.) (Product made) In the order of 1.39 g, and then stirred for 24 hours in a hot bath at 33 ° C., a gradient film coating solution of a titanium alkoxide hydrolyzate mixed with colloidal silica and aluminum nitrate and an organic polymer component ( H) was produced. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of this photocatalyst film itself was 0.29%, and the hydrophilization rate was 2.02 times that of Comparative Example 1.

Example 3
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Trade name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.64 g, colloidal silica C (trade name: IPA-ST-ZL (average particle size 100 nm), Nissan Chemical Industries, Ltd.) (Product made) 0.14 g in order, then stirred in a warm bath at 33 ° C. for 24 hours, and a gradient film coating solution of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component ( H) was produced. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of the photocatalyst film itself was 0.23%, and the hydrophilization rate was 2.48 times that of Comparative Example 1.

Example 4
1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 8.57 g of ethyl cellosolve, and then the hydrolytic condensate (C) of titanium alkoxide prepared in Synthesis Example 1 was dissolved in 11 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Product name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.09 g, Colloidal silica C (Product name: IPA-ST-ZL (average particle size 100 nm), Nissan Chemical Industries, Ltd.) Made in order of 0.70 g, and then stirred in a warm bath at 33 ° C. for 24 hours, and a gradient film coating solution of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component ( H) was produced. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of the photocatalyst film itself was 0.34%, and the hydrophilization rate was 3.43 times that of Comparative Example 1.

Example 5
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Trade name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.64 g, colloidal silica D (trade name: MP-2040 (average particle size 190 nm), manufactured by Nissan Chemical Industries, Ltd.) Mixing in order of 0.10 g, and then stirring in a warm bath at 33 ° C. for 24 hours, a gradient film coating solution (H) of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component Was made. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of this photocatalyst film itself was 0.32%, and the hydrophilization rate was 2.02 times that of Comparative Example 1.

Example 6
1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 8.57 g of ethyl cellosolve, and then the hydrolytic condensate (C) of titanium alkoxide prepared in Synthesis Example 1 was dissolved in 11 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Product name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.50 g, colloidal silica D (Product name: MP-2040 (average particle size 190 nm), manufactured by Nissan Chemical Industries, Ltd.) Mixing in the order of 0.21 g, and then stirring in a warm bath at 33 ° C. for 24 hours, a gradient film coating solution (H) of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component Was made. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of this photocatalyst film was 0.51%, and the hydrophilization rate was 2.75 times that of Comparative Example 1.

Comparative Example 1
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Product name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.78 g in this order, and then stirred in a 33 ° C. warm bath for 24 hours to mix colloidal silica and aluminum nitrate An inclined film coating solution (H) of the hydrolyzed titanium alkoxide and the organic polymer component was prepared. At this time, the amount of colloidal silica A in the coating liquid (H) solid content was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of the photocatalyst film itself was 0.12%.

Comparative Example 2
1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 8.57 g of ethyl cellosolve, and then the hydrolytic condensate (C) of titanium alkoxide prepared in Synthesis Example 1 was dissolved in 11 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica B ( Product name: IPA-ST-L (average particle size 50 nm), manufactured by Nissan Chemical Industries, Ltd. 2.78 g in this order, then stirred in a 33 ° C. warm bath for 24 hours, colloidal silica and aluminum nitrate A gradient film coating solution (H) of a hydrolyzate of titanium alkoxide and an organic polymer component was prepared. At this time, the amount of colloidal silica B in the coating liquid (H) solid content was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of the photocatalyst film itself was 0.35%, and the hydrophilization rate was 0.34 times that of Comparative Example 1.

Comparative Example 3
1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 8.57 g of ethyl cellosolve, and then the hydrolytic condensate (C) of titanium alkoxide prepared in Synthesis Example 1 was dissolved in 11 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica C ( Trade name: IPA-ST-ZL (average particle size 100 nm), manufactured by Nissan Chemical Industries, Ltd.) 2.78 g in order, then stirred in a hot bath at 33 ° C. for 24 hours, colloidal silica and aluminum nitrate A gradient film coating solution (H) of a hydrolyzate of titanium alkoxide and an organic polymer component was prepared. At this time, the amount of colloidal silica C in the coating liquid (H) solid content was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of the photocatalyst film itself was 0.74%, and the hydrophilization rate was 0.35 times that of Comparative Example 1.

Comparative Example 4
1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 8.57 g of ethyl cellosolve, and then the hydrolytic condensate (C) of titanium alkoxide prepared in Synthesis Example 1 was dissolved in 11 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica D ( Product name: MP-2040 (average particle diameter 190 nm), manufactured by Nissan Chemical Industries, Ltd. 2.09 g in order, then stirred in a 33 ° C. warm bath for 24 hours to mix colloidal silica and aluminum nitrate An inclined film coating solution (H) of the hydrolyzed titanium alkoxide and the organic polymer component was prepared. At this time, the amount of colloidal silica D in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of this photocatalyst film itself was 1.69%, and the hydrophilization rate was 0.25 times that of Comparative Example 1.

Comparative Example 5
1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 8.57 g of ethyl cellosolve, and then the hydrolytic condensate (C) of titanium alkoxide prepared in Synthesis Example 1 was dissolved in 11 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Trade name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.64 g, colloidal silica B (trade name: IPA-ST-L (average particle size 50 nm), Nissan Chemical Industries, Ltd.) (Product made) 0.14 g in order, then stirred in a warm bath at 33 ° C. for 24 hours, and a gradient film coating solution of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component ( H) was produced. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of this photocatalyst film was 0.39%, and the hydrophilization rate was 1.45 times that of Comparative Example 1.

Comparative Example 6
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Product name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 0.47 g, colloidal silica B (product name: IPA-ST-L (average particle size 50 nm), Nissan Chemical Industries, Ltd.) (Product made) In order of 2.31 g, and then stirred in a warm bath at 33 ° C. for 24 hours, a gradient film coating liquid of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component ( H) was produced. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of the photocatalyst film itself was 0.19%, and the hydrophilization rate was 0.74 times that of Comparative Example 1.

Comparative Example 7
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Product name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.75 g, colloidal silica C (product name: IPA-ST-ZL (average particle size 100 nm), Nissan Chemical Industries, Ltd.) Made in order of 0.03 g, then stirred in a warm bath at 33 ° C. for 24 hours, and a gradient membrane coating solution of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component ( H) was produced. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of this photocatalyst film itself was 0.21%, and the hydrophilization rate was 1.58 times that of Comparative Example 1.

Comparative Example 8
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Trade name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 1.39 g, colloidal silica C (trade name: IPA-ST-ZL (average particle size 100 nm), Nissan Chemical Industries, Ltd.) (Product made) In the order of 1.39 g, and then stirred for 24 hours in a hot bath at 33 ° C., a gradient film coating solution of a titanium alkoxide hydrolyzate mixed with colloidal silica and aluminum nitrate and an organic polymer component ( H) was produced. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of this photocatalyst film itself was 0.25%, and the hydrophilization rate was 0.72 times that of Comparative Example 1.

Comparative Example 9
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Product name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.75 g, colloidal silica D (Product name: MP-2040 (average particle size 190 nm), manufactured by Nissan Chemical Industries, Ltd.) Mix in the order of 0.02 g, and then stir in a warm bath at 33 ° C. for 24 hours to prepare a gradient film coating solution (H) of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component. Was made. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of this photocatalyst film itself was 0.28%, and the hydrophilization rate was 1.75 times that of Comparative Example 1.

Comparative Example 10
Dissolve 1.22 g of aluminum nitrate nonahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 8.57 g of ethyl cellosolve. 0.03 g was added and stirred well to obtain a solution (G). Subsequently, 1.46 g of the organic polymer component solution (D) prepared in Synthesis Example 2, 47.15 g of methyl isobutyl ketone, 27.78 g of ethyl cellosolve, 20.82 g of the solution (G) described above, and colloidal silica A ( Trade name: IPA-ST (average particle size 20 nm), manufactured by Nissan Chemical Industries, Ltd. 2.36 g, colloidal silica D (trade name: MP-2040 (average particle size 190 nm), manufactured by Nissan Chemical Industries, Ltd.) Mixing in order of 0.31 g, and then stirring in a warm bath at 33 ° C. for 24 hours, a gradient film coating solution (H) of a hydrolyzate of titanium alkoxide mixed with colloidal silica and aluminum nitrate and an organic polymer component Was made. At this time, the total amount of colloidal silica in the solid content of the coating liquid (H) was 30% by mass.
Then, the same operation as Example 1 was performed and the photocatalyst film | membrane which has a photocatalyst layer on the inclined film surface was produced. The haze value of the photocatalyst film itself was 0.65%, and the hydrophilization rate was 2.75 times that of Comparative Example 1.
The results of Examples 1 to 6 and Comparative Examples 1 to 10 are shown in Table 1 above.

As can be seen from Table 1, each of the photocatalyst films of the present invention (Examples 1 to 6) has a hydrophilization rate index of 2 or more, and the haze value of the photocatalyst film itself is less than 0.6%. is there.
On the other hand, Comparative Examples 1 to 9 all have a hydrophilization rate of less than 2. In Comparative Example 10, the hydrophilization rate is as high as 2.75, but the haze value of the photocatalyst film itself is as high as 0.65%.

  The photocatalyst film of the present invention has excellent hydrophilic performance, but exhibits almost no decomposition activity, can suppress the deterioration of the organic base material, has high transparency, has a window material, an automobile side mirror, and a curve. It is suitably used for mirrors, reflectors and the like.

Claims (8)

Content of hydrolysis condensate of titanium alkoxide provided by applying a coating agent containing a complex formed by hydrolysis and condensation of titanium alkoxide and organic polymer compound only once on an organic base material Is a photocatalytic film obtained by exposing the surface of an amorphous titanium oxide film whose surface continuously changes in the depth direction from the surface to a temperature of 100 ° C. or less in the presence of water vapor, In addition to the particles, (a) metal oxide particles A having an average particle size of less than 40 nm and (b) metal oxide particles B having an average particle size of 40 nm or more and less than 90 nm or metal oxide particles C having an average particle size of 90 nm or more and less than 150 nm Or a metal oxide particle D having an average particle size of 150 nm or more and less than 200 nm, and the mixing ratio thereof is expressed by the following relational expressions (1) to (3) on a mass basis.
80/20 ≦ A / B ≦ 45/55 (1)
97/3 ≦ A / C ≦ 70/30 (2)
97/3 ≦ A / D ≦ 88/12 (3)
And a highly transparent photocatalyst film characterized by having irregularities on the surface.   The highly transparent film according to claim 1, which is a photocatalyst film obtained by heat-treating the surface of an amorphous titanium oxide film coated on an organic base material at a temperature of 100 ° C or lower in the presence of moisture. Photocatalytic membrane.   The highly transparent photocatalyst film according to claim 1 or 2, wherein the haze value of the photocatalyst film itself measured in accordance with JIS K 7361 is less than 0.6%.   The highly transparent photocatalyst film according to any one of claims 1 to 3, wherein the metal oxide particles A to D are at least one selected from silica, titania, zirconia, alumina, and magnesia.   The highly transparent photocatalyst film according to claim 4, wherein the metal oxide particles A to D are silica-based particles.   The highly transparent photocatalyst film according to any one of claims 1 to 5, wherein the hydrophilization speed is improved by 2 times or more as compared with a photocatalyst film containing only the metal oxide particles A in addition to the photocatalyst particles.   An article having the highly transparent photocatalyst film according to any one of claims 1 to 6 on the surface of an organic base material.   The article according to claim 7, further comprising a functional film on the surface of the highly transparent photocatalytic film.