JP2003160745A - Film-forming aqueous liquid having electroconductivity and photocatalytic property, its production method and structure equipped with film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film-forming aqueous liquid having high electroconductivity and a photocatalytic property which can exhibit various functions, such as photocatalytic, antibacterial, stainproof, antistatic and electromagnetic shielding properties, to the surfaces of various substrates, such as glasses, ceramics, metals and plastics, and to provide a production method thereof and a structure having the film. <P>SOLUTION: In any process in which a tetravalent titanium salt solution is reacted with a basic solution to obtain a titanium hydroxide, the resulting hydroxide is peroxidized with an oxidizing agent and further heated to convert into an anatase type titanium peroxide resulting in the liquid, an electroconductivity-improving substance fine particle is added and the liquid having the photocatalytic property and the electroconductivity is produced for forming the film containing the electroconductivity-improving substance fine particle and a titanium oxide fine particle with a surface resistance value less than 10<SP>11</SP>Ω/square. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a photocatalytic property and a surface conductivity on a surface of a film-forming object, which is obtained by applying a water solution for forming a film to a film-forming object only by forming a film by applying it or by heat treatment. And a method for producing the same, and a structure having the coating. More specifically, the surface resistance value of the coating is 10 ¹¹
The present invention relates to a water solution for forming a film having photocatalytic performance and electrical conductivity for forming a film having an Ω / □, a method for producing the same, and a structure provided with the film.

More specifically, many proposals and products have been developed in recent years, and various purifying functions such as antifouling, antibacterial, gas decomposition, and decomposition of harmful organic substances, which are exhibited by a photocatalytic function, and a conductive function are used. Aqueous liquid for forming a film having a combination of electric charge that develops, floating dust and gas adhesion, surface adhesion of decomposition intermediate products, electromagnetic shielding properties, and rust prevention performance, a method for producing the same, and a structure including the film. Regarding the body

[0003]

2. Description of the Related Art Titanium-containing substances are used for plate glass, white porcelain,
It is applied to the surface of various materials such as metal plates or building materials such as tiles to form a film made of titanium oxide (titania),
It has been performed for a long time to exhibit various functions such as protection of the surface of a substrate such as prevention of surface contamination, photocatalyst, dielectric, semiconductor, UV cut, and colored coating. As a method for forming the titanium oxide film, a method is known in which a dispersion liquid or titanium compound solution containing fine particles of titanium oxide is applied to the surface of the substrate, and after the application, drying or further low temperature baking is applied. .

It is known that not only titanium dioxide such as anatase-type or rutile-type titanium oxide but also titanium oxide having a peroxo group, that is, titanium peroxide can be used as the titanium oxide used for exhibiting photocatalytic performance. Has been. Regarding the titanium peroxide, it is also known that the amorphous type does not have a catalytic ability, and only the anatase type has a catalytic ability (JP-A-9-124865).

Since the anatase type titanium peroxide has photocatalytic performance as described above, it is also described in the above publication that it is used as a photocatalytic film by forming a film on the surface of the substrate of various structures. As described above, the amorphous type does not have catalytic performance but has excellent binding performance, and it has been proposed to use it as a binder for photocatalyst particles when forming a photocatalyst film (Japanese Patent Laid-Open No. 9-
No. 262481).

As described above, the coating film formed of anatase type titanium peroxide has a photocatalytic performance, and in addition to the photocatalyst composed of other titanium oxides, it also protects the surface of the substrate such as surface contamination prevention, the dielectric, Semiconductor, UV protection,
Although various functions such as a colored coating can be exhibited, it is difficult to say that the coating has sufficient conductivity and it is difficult to use it as an electromagnetic wave shield or an antistatic material.

In particular, it is in a high resistance state at the time of photoexcitation exhibiting photocatalytic performance, and it is very difficult to satisfy electromagnetic wave shielding property or antistatic property. In addition, the performances were not satisfactory even in the non-excitation state. As a result, the photocatalytic function surface tends to be charged, and molecules, intermediate products, or suspended dust decomposed by the photocatalyst are difficult to separate from the function surface, and are adsorbed, adhered, or remain on the function surface, and the photocatalytic activity decreases. There was a problem.

Further, in the case of a photocatalyst such as titanium oxide, H ₂ O in the air is decomposed due to its function when excited, and a hydroxyl group (O
H ^-) are said to produce, is the therein moisture adheres the superhydrophilic phenomenon occurs. At that time, in order to maintain the superhydrophilic phenomenon on the functional film surface and maintain high conductivity, it is premised that water adheres to the hydroxyl groups, but for that purpose, water sprinkling or rainwater on the functional surface is required. Landing is required.

However, when the water is fine, the water evaporates into the atmosphere and returns to its original state, and at the same time, the conductivity decreases, so water spraying is necessary to avoid the decrease, and adsorption and residue remain. The only way to reduce the pollution by water is to remove it by washing with water. Furthermore, it is necessary to wash with water even in places and structures where it is difficult to expect self-cleaning due to natural rainfall. As described above, the substrate surface protection performance based on photocatalytic activity such as surface contamination prevention is not satisfactory.

On the other hand, as a technique for imparting electric conductivity to the surface of the structure, a technique of mixing copper oxide, antimony oxide or the like in the glaze of a tile (Japanese Patent Publication No. 3-349),
There is a glaze in which a powder of tin oxide, iron oxide or the like is partly contained in a non-molten state on the glaze (Japanese Patent Publication No. 4-36229), but in order to obtain the required surface conductivity, The required amount of the material such as copper oxide mixed in becomes large. Further, the mixture of these affects the color development of the glaze, and the designability is restricted.

Other materials that exhibit conductivity include conductive polymers such as polyaniline and polypyrrole, which are electromagnetic wave shielding materials that shield electromagnetic waves generated from mobile phones, televisions, personal computers, home appliances and the like. , Battery electrodes, antistatic agents, capacitors, diodes, various electronic devices such as transistors,
Many researches and developments have been conducted with the expectation that they will be used in electrochromic devices and various sensors.

[0012] This conductive polymer is expected to be used for the above-mentioned applications, and although it has been attempted to form a coating film on the surface of the structure as a liquid agent for that purpose, it is an object of film formation alone. The structure has almost no binding force to the substrate, and in order to improve it, it is used in combination with an organic binder in which a binding component such as a resin is dissolved in an organic solvent, a silica sol, a silicone compound, or a binding aid such as ITO. , Even in that case, the binding property was not sufficient.

Further, there are problems that treatment at a high temperature is required to improve the bonding force, or the fixing strength is not improved as expected. In addition, when an organic substance is used for forming the film, there is also a point that it is not convenient in handling because special consideration needs to be given to the work environment and the like. In addition, the conductive property also changes depending on the state, and the conductivity may not be sufficiently exhibited. As described above, there are various kinds of film forming technology that exhibits photocatalytic performance and film forming technology that exhibits conductive performance, but these are not satisfactory in performance as described above.

Further, not only a film forming technique for individually expressing photocatalytic performance and conductive property, but also a film forming technique for simultaneously expressing both properties has been proposed (Japanese Patent Laid-Open No. 11-3.
155921). The film forming technology is to form a film that exhibits photocatalytic performance and a film that exhibits conductive performance by stacking them, and imparts conductive performance and photocatalytic performance by devising the structure so that both coatings are exposed on the surface. It is a thing.

To further describe the structure, the coating exposed on the surface side has a structure having a large number of small missing portions, and the lower coating is exposed to the outside from the missing portions, so that the structure surface is exposed. It imparts conductivity and photocatalytic performance. For example, a coating that develops conductive performance is formed on the substrate side, and then a coating that develops photocatalytic performance is formed on the surface. At that time, many coatings that develop photocatalytic performance on the surface side are formed. It is necessary to form a small missing part of

As described above, the number of film forming steps is increased as compared with the case of forming a film on the entire surface of the substrate by one coating operation. In addition, in order to make the photocatalytic performance and the conductive performance appropriate, it is necessary to consider the even arrangement of the missing parts and the area ratio that exhibits both performances to be appropriate, and as a result, film formation. The process becomes complicated.

[0017]

As described above, since it is impossible to achieve with the conventional film-forming liquid,
In addition, the appearance of a water solution for forming a film, which can form a film having a conductive property and a photocatalytic property by a simple film forming operation such as coating or spraying, has been desired. Under such circumstances, it has been desired to develop a coating-forming aqueous solution which has a photocatalytic activity and which has a conductivity capable of exhibiting a predetermined performance in electromagnetic wave shielding or antistatic properties.

In particular, a substance such as titanium oxide exhibiting photocatalytic performance has a conductivity that is reduced when the photocatalytic performance is exhibited, and thus has a conductivity capable of exhibiting a predetermined function for electromagnetic wave shielding or antistatic in that state. The appearance of a water solution for forming a film is desired. The present inventor also paid attention to the high functionality and the workability of the titanium oxide, particularly titanium peroxide-containing coating and the coating liquid for forming the coating, and has been making diligent research and development for a long time. Proposes many achievements. Since then, we have continued to earnestly carry out research and development, and as a result, the invention that was proposed this time was successfully developed, and as a result, the above-mentioned problems could be solved.

Therefore, it is an object of the present invention to provide an aqueous solution for forming a film that exhibits the above-mentioned performance, and specifically, the surface resistance value of the film is 10
It is an object of the present invention to provide a water solution for forming a film, which has photocatalytic performance and conductive performance for forming a film having a resistance of less than ¹¹ Ω / □. Another object of the present invention is to provide a water solution for forming a film, which particularly forms a film having a surface resistance value of less than 10 ¹¹ Ω / □ when the photocatalytic performance is exhibited.

[0020]

In order to solve the above-mentioned problems, the present invention provides a film forming water solution, a method for producing the same, and a structure having the film, wherein the film forming water solution is Forming a film having a surface resistance value of less than 10 ¹¹ Ω / □, containing anatase type titanium oxide fine particles having a peroxo group and fine particles of a conductivity enhancing substance, and forming a film having photocatalytic performance and conductivity. belongs to.

The method for producing the film-forming aqueous solution is as follows:
A salt solution of tetravalent titanium is reacted with a basic solution to form titanium hydroxide, and the hydroxide is peroxidized with an oxidizing agent and further heat-treated to transform it into anatase-type titanium peroxide. In any of the steps of forming a water solution for forming a film by adding fine particles of a conductivity improving substance and containing the fine particles of a conductivity improving substance and fine particles of titanium oxide and having a surface resistance value of less than 10 ¹¹ Ω / □. A film forming water liquid having photocatalytic performance and conductivity for forming a film is produced. Furthermore, the structure has a coating film formed by the water solution.

The above is related to the technique of the water solution for forming a film containing the anatase type titanium oxide fine particles which is a preferred embodiment of the present invention. In the present invention, however, the amorphous type titanium oxide fine particles and the electroconductivity are used. It is possible to form a film having a surface resistance value of less than 10 ¹¹ Ω / □ and having photocatalytic performance and conductivity even when a water solution for forming a film containing fine particles of an enhancing substance is used. The technology is as follows. That is, the aqueous solution for forming a film contains amorphous titanium oxide fine particles having a peroxo group and fine particles of a conductivity improving substance, and a film having a surface resistance value of less than 10 ¹¹ Ω / □ by heat treatment after film formation. To form a film having photocatalytic performance and conductivity.

Further, the manufacturing method thereof is that a salt solution of tetravalent titanium is reacted with a basic solution to form a hydroxide of titanium, and this hydroxide is peroxoed with an oxidizing agent to form an amorphous peroxide. In any process of forming titanium, the conductivity improving substance fine particles are added to contain the conductivity improving substance fine particles and the titanium oxide fine particles, and the surface resistance value is 10 ¹¹ Ω / A water solution for forming a film having photocatalytic performance and electrical conductivity for forming a film of less than □ is produced. Further, the structure has a coating film formed by the aqueous solution and then heat-treated.

The anatase-type titanium oxide fine particles having a peroxo group and the electroconductivity-improving substance particles coexist in the film formed by the film-forming aqueous solution of the present invention. As a result, the photocatalyst is used. It is possible to exhibit both properties of high performance and high conductivity with a surface resistance value of less than 10 ¹¹ Ω / □ capable of appropriately exhibiting electromagnetic wave shielding or antistatic property.

That is, the function based on the photocatalytic ability expressed by the titanium oxide having a peroxo group, is a property of reducing charge, electromagnetic shielding property, antifouling property, antibacterial property, antifogging property, superhydrophilic property or degradability of organic substances. And the like, and in addition to these, the coexistence of a conductivity improving inorganic substance such as tin, silver, copper, indium, or a conductivity improving substance such as a conductive polymer causes the photocatalytic performance to develop. Even when it is being carried out, it is possible to develop high conductivity performance with a surface resistance value of less than 10 ¹¹ Ω / □, and as a result, it is possible to develop even more excellent performance in terms of antistatic properties, electromagnetic shielding properties, and the like.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention provides a water solution for forming a film, a method for producing the same, and a structure having the film as described above. The water solution for forming a film is anatase-type titanium having a peroxo group. Contains oxide fine particles and fine particles of conductivity improving substance, and has a surface resistance value of 10 ¹¹ Ω / □.
It forms a film having photocatalytic performance and electrical conductivity.

Further, in the method for producing the aqueous solution, a salt solution of tetravalent titanium is reacted with a basic solution to form a hydroxide of titanium, and the hydroxide is peroxo-ized with an oxidizing agent,
In any process of transferring to anatase-type titanium peroxide by heat treatment to form an aqueous solution for forming a film, the conductivity improving substance fine particles are added, and the conductivity improving substance fine particles and titanium oxide fine particles are added. A water solution for forming a coating, which has photocatalytic performance and conductivity for forming a coating having a surface resistance value of less than 10 ¹¹ Ω / □, is produced. Further, the structure has a coating film formed by the water solution.

The above is related to the technique of the water solution for forming a film containing the anatase type titanium oxide fine particles, which is a preferred embodiment of the present invention. In the present invention, the amorphous type titanium oxide fine particles and the electroconductivity are used. It is possible to form a film having a surface resistance value of less than 10 ¹¹ Ω / □ and having photocatalytic performance and conductivity even when a water solution for forming a film containing fine particles of an enhancing substance is used. The technology is as follows. That is, the aqueous solution for forming a film contains amorphous titanium oxide fine particles having a peroxo group and fine particles of a conductivity improving substance, and a film having a surface resistance value of less than 10 ¹¹ Ω / □ by heat treatment after film formation. To form a coating having photocatalytic performance and conductivity.

Further, the manufacturing method thereof is such that a salt solution of tetravalent titanium is reacted with a basic solution to form titanium hydroxide, and this hydroxide is peroxo-ized with an oxidizing agent to form an amorphous peroxide. In any process of forming titanium, the conductivity improving substance fine particles are added to contain the conductivity improving substance fine particles and the titanium oxide fine particles, and the surface resistance value is 10 ¹¹ Ω / A water solution for forming a film having photocatalytic performance and electrical conductivity for forming a film of less than □ is produced. Further, the structure has a coating film formed by the aqueous solution and then heat-treated.

Used in the production of the film-forming aqueous solution of the present invention
As a tetravalent titanium salt solution, ammonia water, caustic so can be used.
Orthotitanic acid when reacted with a basic solution such as da solution
(H _FourTiO_Four) Shaped titanium hydroxide gel, also called
Various titanium compounds can be used if they can be made,
For example, titanium tetrachloride, titanium sulfate, titanium nitrate
Or water-soluble inorganic acid salt of titanium such as titanium phosphate
is there. In addition, water-soluble organic acid salts such as titanium oxalate are also examples.
I can show you. Among these various titanium compounds,
Titanium in titanium compound in the produced water solution for film formation
Titanium tetrachloride is preferred because no other components remain.

Various basic solutions can be used as the basic solution to be reacted with the salt solution of tetravalent titanium as long as it can form a gel of titanium hydroxide by reacting with the salt solution of tetravalent titanium. Examples thereof include ammonia water, caustic soda solution, sodium carbonate solution, caustic potash solution, and the like, and ammonia water is preferable. As the oxidizing agent for oxidizing the titanium hydroxide formed thereafter, various oxidizing agents can be used without limitation as long as they can form a peroxodide after oxidation, but in the produced film forming solution,
Hydrogen peroxide that does not produce residues such as metal ions or acid ions is desirable.

The concentration of both the tetravalent titanium salt solution and the basic solution is not particularly limited as long as the concentration during the reaction is within the range in which a titanium hydroxide gel can be formed, but it is relatively dilute. A good solution is good. Specifically, the tetravalent titanium salt solution is preferably 5 to 0.01 wt%, and more preferably 0.9 to 0.3 wt%. Also, the basic solution is 10
~ 0.5 wt% is good, preferably 4.0-2.0w
t% is good. Particularly, when ammonia is used in the basic solution, the concentration is preferably 10 to 0.5 wt% within the above range, and more preferably 4.0 to 2.0 wt%.

As the conductivity improving substance, various substances such as metal salts can be used as long as the surface resistance value of the formed coating film is less than 10 ¹¹ Ω / □. In particular, the conductivity is lowered during photoexcitation, which is when the photocatalytic performance is exhibited, and it is desirable that the surface resistance of the film can be made less than 10 ¹¹ Ω / □ even at that time. Examples of the metal salt include aluminum, tin, chromium, nickel,
There are metal salts such as antimony, iron, silver, cesium, indium, cerium, selenium, copper, manganese, calcium, platinum, tungsten, zirconium, zinc, etc. A substance or an oxide can also be used.

More specifically, the substance names of these substances are aluminum chloride, stannous chloride and stannic chloride, chromium chloride, nickel chloride, ferrous and antimony chloride, ferrous and ferric chloride, and silver nitrate. Cesium chloride, indium trichloride, cerium chloride, selenium tetrachloride, cupric chloride,
Manganese chloride, calcium chloride, secondary platinum chloride, tungsten tetrachloride, tungsten oxydichloride, potassium tungstate, secondary gold chloride, zirconium oxychloride,
Various metal salts such as zinc chloride can be exemplified. Examples of compounds other than metal salts include indium hydroxide, silicotungstic acid, silica sol, calcium hydroxide and the like.

As the conductivity improving substance, other than the above-mentioned inorganic substances can be used, and examples thereof include conductive polymers such as polyaniline and polypyrrole. Many substances have already been developed for this conductive polymer, and in addition to the above-mentioned polyaniline and polypyrrole, polythiophene, polythiophene vinylene, polyisothianaphthene, polyacetylene, polyalkylpyrrole, and polyalkylthiophene. , Poly-p-phenylene,
Polyphenylene vinylene, polymethoxyphenylene, polyphenylene sulfide, polyphenylene oxide,
Examples thereof include polymers of polyanthracene, polynaphthalene, polypyrene, polyazulene and derivatives thereof, and any of these can be used. These conductivity improving substances can be used alone or as a mixture of two or more kinds.

These conductive polymers are doped
It is possible to improve the conductivity by this doping.
However, as a result, the electromagnetic wave shielding property is improved.
Then, it is preferable to dope. With that dopant
As a result, alkali metals such as Li, Na, K, and Ca
Donor type dopant such as Lucari earth metal, or Cl
₂, Br₂, I₂Such as halogen, PF₃, AsF_Five, BF₃etc
Lewis acid, HF, HCl, HNO₃, H₂SO_Four, HC
10_FourProtic acid such as FeCl₃, FeOCl₂, Ti
Cl_Four, WCl₃Transition metal compounds such as Cl^-, Br^-, I
^-, ClO_Four ^-, PF₃ ^-, BF₃ ^-, AsF₃ ^-Electrolyte such as
Nion acceptor type dopants can be used
It

The characteristic of the conductivity of these conductive polymers is that the oxidation or reduction reaction, especially the electric redox reaction,
It is also known to change by reaction with an acid or a base. In particular, a conductive polymer having the functions of an electron donor and an electron acceptor exhibits changes in electrical characteristics due to these reactions. For example, polyaniline is known to change according to the reaction formula of the following Formula 1 by an oxidation or reduction reaction or a reaction with an acid or a base (“New Polymer One Point-5 Conductive Polymer”, Yoshimura). Susumu, The Polymer Society of Japan, pp. 17-18).

[0038]

[Chemical 1]

As a result, when polyaniline is oxidized, its electrical conductivity is metallic and its color is green, and when it is reduced, its electrical conductivity is insulating and changes from blue to colorless and transparent. When it is acidified by reacting with an acid, the conductivity is improved and becomes green, and when it is made basic by reacting with a base, the conductivity is decreased and the color is blue.

Further, substances other than the above can be used as the conductivity improving substance, and there is a group of substances called ion conductive type which adsorb moisture in the air and move electricity by ions. Specifically, there are inorganic substances such as potassium chloride, sodium chloride, or siloxane, and glycerin fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene alkyl amine, alkyl sulfonic acid, which is an antistatic surfactant. There are organic substances such as salts, tetraalkylammonium salts, alkylbetaines, those having a polyether group having a polyethylene oxide chain as a hydrophilic group component, and copolymers.

In the production of the water solution for forming a coating film of the present invention, first, a salt solution of tetravalent titanium is reacted with a basic solution to form a titanium hydroxide gel. The concentration and temperature of the reaction solution at that time are not particularly limited, but it is preferable to carry out the reaction in a dilute solution and at room temperature. This reaction is a neutralization reaction, and it is desirable to carry out the reaction until it is confirmed that the pH becomes 7 from acidic to neutral. After the reaction, the formed titanium hydroxide gel is preferably subjected to solid-liquid separation by gravity settling or centrifugation, and after separation, the gel is preferably washed with water.

The conductivity-improving substance used in the present invention is preferably made to coexist when a salt solution of tetravalent titanium is reacted with a basic solution to form titanium hydroxide, and for that purpose, a hydroxide is formed. It is preferable to add it to a salt solution of tetravalent titanium before the reaction by addition or to add it to the reaction system during the reaction. By doing so, depending on the conductivity-enhancing substance added, a hydroxide can be formed and coprecipitated during the hydroxide formation reaction, similar to titanium hydroxide.

The titanium hydroxide obtained as described above is added with an oxidizing agent such as hydrogen peroxide and peroxidized to form amorphous titanium peroxide of ultrafine particles having conductivity. The particle size is 2 nm
-10 nm. The aqueous solution for forming a film containing the amorphous titanium peroxide thus obtained can form a film excellent in fixing force as it is, but has no catalytic performance.

However, the surface resistance value is 10 ¹¹ Ω / □ by using an aqueous solution containing amorphous titanium peroxide.
It is also possible to form a coating having a photocatalytic performance and a conductive performance at less than, in that case, also in the same manner as in the case of a water solution for forming a coating containing anatase type titanium peroxide, the conductivity improving substance fine particles and titanium oxide. It is necessary to coexist with fine particles of a substance, and for that reason, it is necessary to add fine particles of a conductivity improving substance in the process until an aqueous solution containing amorphous titanium peroxide is prepared as shown in FIG. is necessary.

Using this, the surface resistance value is 10 ¹¹ Ω.
In order to form a film having a photocatalytic performance and a conductive property of less than / □, it is necessary to perform heat treatment after forming a film by coating, unlike the case of a water solution for forming a film containing anatase type titanium peroxide. Is. The heat treatment at that time is
It is for transferring amorphous titanium peroxide to anatase type, and is 5 to 6 at a temperature of 150 to 650 ° C.
It is better to carry out for 0 minutes, preferably at a temperature of 200 to 550.
It is good to carry out at 30 degreeC for 15 to 30 minutes.

On the other hand, in order to produce a water solution for forming a coating film containing anatase-type titanium peroxide, which is a preferred embodiment of the present invention, the ultrafine particle amorphous titanium titanium dispersion liquid formed above is prepared. Is heated, thereby transferring to the anatase form. The heating temperature at that time is 80 to 20.
0 ° C is good, and heating at atmospheric pressure is particularly convenient and preferable,
The water solution for film formation thus obtained has high transparency. Therefore, the formed film has high transparency, is suitable for applications requiring visual performance or decorative performance, and exhibits hydrophilicity even in a dark place. Further, the coating film has a surface resistance value of less than 10 ¹¹ Ω / □ and has photocatalytic performance and conductive performance.

In particular, when producing a water solution for forming a film,
During the reaction between the conductivity improving compound and the salt solution of tetravalent titanium with the basic solution, both are co-precipitated as hydroxides, then the titanium oxides are oxidized to peroxo, and then heated to transform into anatase type. With this, a highly transparent dispersion can be formed, and when a film is formed using this, a highly transparent hydrophilic film can be formed, and as a result, visibility or decorativeness is important for buildings. It is suitable for a transparent transparent substrate such as a window glass, an optical glass or a plastic plate. When copper chloride and ferric chloride are used as the conductivity improving substance, it is preferable to add the compounds after peroxolation.

Hereinafter, embodiments of the method for producing a water solution for forming a coating film of the present invention will be described in more detail with reference to the drawings, focusing on preferred embodiments. The film forming aqueous solution of the present invention is produced via amorphous titanium peroxide, and can be produced in various modes shown in FIG. In producing the amorphous titanium peroxide, first, a high-concentration titanium tetrachloride solution and ammonia water are diluted. Dilution has a concentration of 5.
It is preferable to carry out so as to be 0 to 0.01% by weight and 10.0 to 0.5% by weight, preferably 0.7 to
It is preferable to make it 0.3% by weight and 4.0 to 2.0% by weight.

After the dilution, both solutions are mixed to form a titanium hydroxide gel, and it is preferable that the conductivity improving substance coexist in the reaction system during the reaction, and therefore, the titanium tetrachloride solution is mixed in the titanium tetrachloride solution before the mixing. It is preferable to mix a conductivity enhancing substance with the above. As the conductivity improving substance, various substances can be used as described above, but copper chloride, first and second tin chlorides, first and second iron chlorides, zinc chloride, indium trichloride and the like are preferable. When the conductivity improving substance is mixed at the above-mentioned time point, depending on the conductivity improving substance to be mixed, a hydroxide is formed in the same manner as titanium hydroxide during the hydroxide forming reaction and coprecipitates.

The reaction liquid temperature of the titanium oxide forming reaction is not particularly limited, but it is preferably carried out at room temperature. This reaction is a neutralization reaction, and it is desirable to carry out the reaction to the extent that it can be confirmed that the pH becomes 7 from acidic to neutral. After the reaction, the titanium hydroxide gel formed is subjected to solid-liquid separation by gravity sedimentation or centrifugation,
After separation, it is preferable to wash with water to remove coexisting anions such as chlorine ions from the gel.

Next, the titanium oxide will be peroxo-oxidized by the oxidizing agent, but it is preferable to cool it before that. Cooling at that time is preferably performed so that titanium hydroxide has a temperature of 1 to 5 ° C. Hydrogen peroxide is preferably used as an oxidizing agent for peroxidation, and the concentration thereof is not particularly limited, but is preferably 30 to 40%. The oxidizing agent is not limited to hydrogen peroxide,
As described above, various compounds can be used as long as they can form a peroxo compound, that is, a titanium peroxide.

By mixing titanium oxide and hydrogen peroxide as described above, the peroxonation reaction gradually progresses,
A dispersion of amorphous titanium peroxide is formed. The resulting dispersion is usually yellow, but depending on the conductivity-enhancing substance used, it is affected by the substance and becomes green or blue. In addition, in order to obtain a dispersion having excellent transparency, the particle size of the ultrafine particles is preferably about 2 nm to 20 nm.
When the thickness is less than or equal to nm, the transparency becomes high, which is desirable.

The coating formed by this amorphous titanium peroxide-containing dispersion is hydrophobic, and as a result, a coating having a strong adhesion force can be formed not only on the hydrophilic substrate but also on the hydrophobic substrate. Also, the coating has no catalytic performance, so that the substrate can avoid oxidative degradation due to light. Therefore, this dispersion is preferably used as a primer when forming a film on a plastic with the water solution for forming a film of the present invention.

Even when a film is formed using this dispersion, titanium peroxide can be transferred from the amorphous type to the anatase type by heat treatment after film formation as described above. When the electroconductivity-improving substance coexists, the coating film can have a surface resistance value of less than 10 ¹¹ Ω / □ and have photocatalytic performance and conductive performance, which is the coating liquid of the present invention.

The conversion of amorphous titanium peroxide in the dispersion liquid produced as described above to the anatase type is
This can be done by heating the dispersion. The heating temperature at that time may be 80 to 200 ° C., preferably 9
0-120 degreeC is good. Further, the heating can be performed only by electricity or combustion heat, but it is preferable to use heating by electromagnetic waves in combination with these to shorten the heating time as much as possible.

When the combined heating is adopted, the transition from the amorphous type to the anatase type can be shortened, the growth and aggregation of the particle size of the ultrafine particles can be suppressed, and the peroxo group can be reduced and H ₂ can be reduced. A transparent dispersion liquid that does not weaken the repulsive force (Zeta potential) with O is obtained. The particle size of the ultrafine particles of the anatase-type titanium peroxide thus obtained is preferably 2 to 20 nm, and more preferably 10 nm or less.

Regarding the timing of addition of the conductivity improving substance in the method for producing a water solution for forming a coating film of the present invention, as described above, it may be before or during the reaction between the salt solution of tetravalent titanium such as titanium tetrachloride and the basic solution. As described above, it is preferable that excellent properties can be obtained with respect to various properties such as transparency, conductivity, and stickiness.

However, regarding the addition timing,
A water solution for forming a film can be produced by adopting a time other than the above, and as the time, a concentration adjusting film after ultrafiltration performed after precipitation gel formation after solid-liquid separation before washing with water and after peroxidation reaction is performed. For example, it may be the time of manufacturing the forming solution or the time of manufacturing the concentration-adjusting film forming solution after ultrafiltration performed after the anatase-type transition.

As the object of use of the water solution for forming a coating film of the present invention, those which are required to exhibit both photocatalytic performance and high conductive performance are preferable. Regarding their performance,
More specifically, performance based on photocatalytic performance includes antibacterial performance, antifouling performance, gas decomposition performance, antifogging performance, etc., and performance based on high conductivity performance includes antistatic performance and rust resistance. It has electromagnetic shielding properties.

Therefore, the object to be used is preferably various materials or structures which are required to exhibit the above-mentioned specific performance based on both the photocatalytic performance and the high conductive performance. Examples of these materials include plate glass, ceramics, metal plates such as stainless steel and aluminum, plastic plates such as acrylic, polycarbonate and PET, cotton cloth and fibers.

As the structure, a building, a window glass of an automobile, a vehicle exterior material of an automobile, a tank, various aquariums for ornamental use, pipes of metal, plastic, etc., sanitary ware, glasses, lenses, lenses Examples thereof include a filter, a hot water storage device, a bathtub device, a washbasin device, a sink, a door handle, a water faucet, a road mirror, a semiconductor material such as a substrate, and various parts such as internal parts of a copying machine.

As described above, the film formed from the water solution for forming a film of the present invention is excellent in conductivity, and as a result, when a film is formed on the inner surface of a pipe such as metal or plastic which is hard to exhibit photocatalytic activity. Also, contaminants such as soft or hard scale, slime or iron rust hardly form or adhere to the inner surface of the pipe, and have excellent antifouling performance.
In particular, when it is used for a water pipe, scale, slime or rust hardly occurs, which is preferable.

Although the amorphous titanium peroxide dispersion produced in the process of producing the anatase-type titanium peroxide-containing water solution for forming a film of the present invention can form a film excellent in adhesion to various structures. However, as described above, there is no photocatalytic ability just by forming a film. As a result, even when the structure substrate is plastic, there is no danger of decomposition by sunlight, and when a film is formed on the plastic by the water solution for forming a film of the present invention, the film formed by the dispersion liquid is used as a base film (primer film). ) Is preferable.

Further, since the coating film formed by the coating liquid and the dispersion liquid of the present invention is excellent in durability, binding property and transparency, it can be used for window glass or acrylic, polycarbonate, PET. In the case of a transparent plastic plate or container such as the above, it is preferable because it has excellent visual performance as well as antifouling performance and antifogging performance.

[0065]

EXAMPLES Examples for producing the water solution for forming a film of the present invention and comparative examples for producing a comparative control aqueous solution will be described below. In addition, a conductivity evaluation test and a photocatalytic performance evaluation test are performed using the evaluation samples formed by using the examples and the comparative examples in combination, and the evaluation test procedures and results thereof will be described, but the present invention is not limited to these. It is needless to say that the present invention is not limited by the examples and the evaluation test, and is specified by the description of the claims.

[Example 1] Purity of 99.9 in 500 ml of pure water
9% InCl ₃ · xH ₂ O (manufactured by Soegawa Rikagaku Co., Ltd.) 0.77
To a solution in which 2 g was completely dissolved, 10 g of 50% titanium tetrachloride solution (Sumitomo Sitix Co., Ltd.) was further added, and pure water was added to 1000 ml to prepare a solution. 25% ammonia water (manufactured by Takasugi Pharmaceutical Co., Ltd.) was diluted 10 times, and the pH was adjusted to 7.0 by adding ammonia water to precipitate a mixture of indium hydroxide and titanium hydroxide.

Washing the precipitate with pure water until the conductivity in the supernatant liquid was 0.8 mS / m or less, and when the conductivity was 0.724 mS / m, the washing was completed. 308g of liquid containing 64wt% hydroxide
Was made. Then, while cooling the contained liquid to 1 to 5 ° C, 56% of 35% hydrogen peroxide (Taiki Yakuhin Kogyo Co., Ltd.) was added.
When g was added and stirred for 16 hours, 360 g of a dispersion liquid of yellow-brown transparent indium-doped amorphous titanium peroxide having a concentration of 0.73 wt% was obtained.

100 g of the obtained amorphous titanium peroxide dispersion was weighed and heated at 100 ° C. for 5 hours to obtain 66 g of a 1.1 wt% concentration of the pale yellow indium-doped anatase titanium peroxide sol. Was given. This is diluted with pure water to form a film containing anatase type titanium peroxide at a concentration of 0.85 wt% (Ti equivalent, unless otherwise specified, titanium equivalent is used in the present specification) 88 g of the water solution was prepared.

[Example 2] To 500 g of pure water, 2.5 g of 30 wt% silica sol and 10 g of 50 wt% titanium tetrachloride solution (manufactured by Sumitomo Sitix Corporation) were added, and pure water was added to 1000 g.
Prepare the solution. Ammonia water obtained by diluting 25% ammonia water (manufactured by Takasugi Pharmaceutical Co., Ltd.) 10 times was added dropwise to the mixture to adjust the pH to 6.9 to precipitate a mixture of silica and titanium hydroxide. This precipitate was continuously washed with pure water until the conductivity in the supernatant became 0.8 mS / m or less, and when the conductivity was 0.688 mS / m, the washing was completed. The solution containing hydroxide of 350
g produced.

Next, while cooling the contained liquid to 1 to 5 ° C., 25% hydrogen peroxide (Taiki Yakuhin Kogyo Co., Ltd.) was added to 25%.
After adding g and stirring for 16 hours, 370 g of a dispersion of silica-doped amorphous titanium peroxide having a concentration of 1.05 wt% was obtained. 100 g of the obtained amorphous titanium peroxide dispersion was weighed and heated at 100 ° C. for 5 hours to obtain 60 g of silica-doped anatase titanium peroxide sol at a concentration of 1.72 wt%.

Then, this was diluted with pure water to prepare 120 g of a dispersion liquid having an anatase type titanium peroxide concentration of 0.85 wt%. This anatase type titanium peroxide 0.85wt
The concentration of silver nitrate is 0.005 with respect to 60 g of the dispersion having a concentration of 0.5%.
0.050 g was added so as to be mol / l to prepare an anatase type titanium peroxide dispersion liquid for forming a film, which was doped with silica and silver.

[Example 3] 10 g of 50 wt% titanium tetrachloride solution (manufactured by Sumitomo Sitix Co., Ltd.) was added to 500 g of pure water, and pure water was added to 1000 g to prepare a solution. 2 to this
Diluted ammonia water prepared by diluting 5% ammonia water (manufactured by Takasugi Pharmaceutical Co., Ltd.) 10 times was added dropwise to adjust the pH to 6.9 to precipitate titanium hydroxide. This precipitate is continuously washed with pure water until the conductivity of the supernatant liquid becomes 0.8 mS / m or less, and when the conductivity is 0.738 mS / m, the washing is terminated and water having a concentration of 0.73 wt% is added. 430 g of an oxide-containing liquid was prepared.

Next, while cooling this contained liquid to 1 to 5 ° C., 25% hydrogen peroxide (Taiki Yakuhin Kogyo Co., Ltd.) was added to 25%.
Add g and stir for 16 hours to give 0.86 wt% of light yellowish brown
450 g of an amorphous titanium peroxide dispersion having a concentration was obtained. 100 g of this titanium peroxide dispersion was weighed and
When heated at 0 ° C. for 5 hours, 55 g of a pale yellow anatase type titanium peroxide dispersion was obtained at a concentration of 1.52 wt%.

This was diluted with pure water to prepare 98 g of a dispersion liquid having a concentration of 0.85 wt% of anatase type titanium peroxide.
This dispersion contains 4 wt% of conductive polymer polyaniline with respect to the Ti content (D1500 manufactured by Olmecon, Germany).
W) was mixed such that titanium: polyaniline = 1: 4 (weight ratio) to prepare an anatase-type titanium peroxide dispersion liquid doped with polyaniline.

Comparative Example 1 10 g of a 50 wt% titanium tetrachloride solution (manufactured by Sumitomo Sitix Co., Ltd.) was added to 500 g of pure water, and pure water was added to 1000 g to prepare a solution. 2 to this
Ammonia water diluted 10 times with 5% ammonia water (manufactured by Takasugi Pharmaceutical Co., Ltd.) was added dropwise to adjust the pH to 6.9 to precipitate titanium hydroxide.

The precipitate was washed with pure water until the conductivity in the supernatant became 0.8 mS / m or less, and when the conductivity was 0.738 mS / m, the washing was completed. 430 g of the liquid containing 73 wt% hydroxide
Was made. Next, while cooling the contained liquid to 1 to 5 ° C, 25% hydrogen peroxide (Taiki Yakuhin Kogyo Co., Ltd.)
After adding g and stirring for 16 hours, 450 g of a dispersion liquid of amorphous titanium peroxide having a light yellowish brown color of 0.86 wt% concentration was obtained.

[Comparative Example 2] 100 g of the amorphous titanium peroxide dispersion obtained in Comparative Example 1 was weighed and heated at 100 ° C. for 5 hours.
When heated for 55 hours, 55 g of a pale yellow anatase type titanium peroxide dispersion was obtained at a concentration of 1.52 wt%. This was diluted with pure water to prepare 98 g of anatase-type titanium peroxide dispersion liquid for forming a film having a concentration of 0.85 wt%.

Comparative Example 3 0.15 mol of a conductive surfactant (Prophan 128EX): Sanyo Kasei Co., Ltd. was added to 1 L of the anatase type titanium peroxide 0.85 wt% concentration dispersion liquid obtained in Comparative Example 2. Then, an anatase type titanium peroxide dispersion liquid for forming a film was prepared.

Comparative Example 4 Anatase-type titanium peroxide dispersion obtained in Comparative Example 2 and silica sol (Nissan Chemical Co., Ltd.)
Was mixed with each other in a weight ratio of 1: 1 to prepare a silica-mixed anatase-type titanium peroxide dispersion for forming a film.

[Outline of Performance Evaluation Test of Film Formed by Water for Forming Film] Using the water liquid for film formation of the above-mentioned Examples and Comparative Examples, samples for performance evaluation were prepared. The performance was evaluated. The conductive performance was evaluated by measuring the surface resistance value of the formed film. The measurement was carried out under the condition that the photocatalytic performance was exhibited and under the condition that the photocatalytic performance was not exhibited.

[Preparation of Evaluation Sample] Except for Samples 4 and 5, evaluation samples were prepared as follows. Ie 1
A float transparent glass plate having a thickness of 00 × 100 mm and a thickness of 4 mm was coated with the water solution for forming a coating film of the above-mentioned Example or Comparative Example to form a film, and then dried at 100 ° C. for 10 minutes to form a film, and an evaluation sample was prepared. It was made. Table 1 shows the water solution for film formation used in the preparation, the thickness of the formed film, and the like.

[0082]

[Table 1]

In the sample 4 out of the excluded samples, the film-forming substrate is not a plate glass but a polycarbonate plate (50 × 90 m) which may be decomposed by a photocatalytic reaction.
m) was used to form a film having a two-layer laminated structure. The specific preparation method is as follows. First, the amorphous titanium peroxide dispersion obtained in Comparative Example 1 was diluted into the polycarbonate plate to prepare a dispersion of amorphous titanium peroxide having a concentration of 0.4 wt%.
100 cm ² (wet) was applied, and a film was formed to a thickness of 0.07 μm.

Next, the anatase-type titanium peroxide dispersion liquid doped with silica and silver obtained in Example 2 was diluted to give anatase-type titanium peroxide with an anatase-type titanium peroxide concentration of 0.40 wt%. A titanium dispersion was prepared. 0.25 g / 100 cm ² (wet) of this dispersion liquid
After coating, a film is formed to have a thickness of 0.15 μm when dried, and 10
It was dried at 0 ° C. for 10 minutes.

In the same manner as in the case of the sample 4 other than the sample 4, the sample 5 uses the float method transparent plate glass as the film forming substrate, and the indium doped in the intermediate step of Example 1 is added to the sample. A dispersion liquid of amorphous titanium peroxide having a concentration of 96 wt% was added to 0.6 g / 100 cm ² (we
and then dried at room temperature (film thickness after drying was 0.3 μm).
After drying, it was heat-treated in an electric furnace at 200 ° C. for 15 minutes to be transferred to an anatase type film to form an anatase type coating film doped with indium, which was used as an evaluation sample 5.

[Conductivity Evaluation Test] Conductivity performance evaluation test was carried out as follows. That is, the surface resistance value of each sample was measured in the following two modes. (1) The sample prepared above was again heat-dried at 80 ° C. for 15 minutes to remove surface moisture (2) Immediately after drying, a black light (irradiation wavelength UV360
Irradiation is continued at a position of 20 mm apart from 15 W.

In the above measurement, the surface resistance value is measured while the black light irradiation is being continued, because the reason is to measure the photocatalytic performance manifestation state, that is, the conductivity at the time of photoexcitation. Also, for the measurement, Lorester G
P and Lorester UP were used. At this time, two types of measuring instruments are used as described above because one type of measuring instrument cannot cover the entire range, and LORESTER GP has a surface resistance value in the range of 10 ⁻³ to 10 ⁷ and LORESTER UP. Is 10 ⁴ ~
It is used in the range of 10 ¹³ .

[Catalyst Performance Evaluation Test] The catalyst performance evaluation test is
For each sample, a dye having an organic compound as a pigment (red ink manufactured by Pilot Co., Ltd. (commercial product)) was applied to the surface of the sample with pure water.
Dilute twice and spray it with 0.5g / 100cm
^The sample surface was colored by spraying with ² . After that, it was dried and exposed to direct sunlight at a temperature of 16 ° C. and a humidity of 60%, and the time until decoloring was measured to evaluate the redox power of the photocatalyst with respect to an organic bond.

[Results of Conductive Performance Evaluation Test] The results of the conductive performance evaluation test are shown in Table 2. According to the results, Samples 1 to 1 having a coating film formed from the coating liquid according to the present invention were used.
No. 5 has a surface resistance value of less than 10 ¹¹ Ω / □ immediately after removing moisture and during black light irradiation, that is, while developing photocatalytic activity. It is also found that the coating film formed by the present invention has a smaller difference in surface resistance value between when the catalytic ability is being expressed and when the catalytic ability is not being expressed, as compared with the coating film formed by the comparative example. Further, it can be seen that the coating of Sample 2 formed from the anatase type titanium peroxide dispersion liquid doped with silica and silver has particularly excellent conductivity.

[0090]

[Table 2]

Sample 4 was obtained by forming an amorphous titanium peroxide film having no photocatalytic performance on a polycarbonate plate which is a plastic, and then forming an anatase type titanium peroxide film having photocatalytic performance.
Also in this case, the anatase type titanium peroxide coating on the surface is
It can be seen that it has the conductivity specified in the present invention. In addition,
By adopting such a laminated structure, it is possible to suppress decomposition of the plastic plate which is the substrate by the photocatalyst. Further, Sample 5 is an amorphous titanium peroxide coating film formed by heat treatment after film formation and converted to anatase type, and it can be seen that even in that case, it has the conductivity specified in the present invention.

[Results of Photocatalyst Performance Evaluation Test] The results of the photocatalyst performance evaluation test are shown in Table 3. According to the results,
It can be seen that, except for Sample 6 in which the amorphous titanium peroxide coating film was formed, the anatase-type titanium peroxide coating film was exposed and formed in all the samples, and thus each sample has photocatalytic performance. In particular, the coating film formed from the anatase type titanium peroxide dispersion liquid doped with silica and silver has the best photocatalytic performance. It can be seen from Tables 2 and 3 that this coating is excellent in both photocatalytic performance and conductivity.

[0093]

[Table 3]

Sample 5 was prepared by forming an amorphous titanium peroxide coating film and then transferring it to the anatase type. It can be seen that the photocatalytic activity is also exhibited in that case. Further, Sample 4 is a sample in which an amorphous titanium peroxide coating having no photocatalytic ability was formed first, and then an anatase titanium peroxide coating having photocatalytic performance was formed, because of concern about decomposition of the plastic plate by the photocatalyst as described above. However, as compared with the film of Sample 2 in the case where the film was formed by itself, it has a decoloring time nearly four times, and it seems that the photocatalytic activity is considerably reduced.

In particular, the coating film of sample 2 is a coating film formed from the anatase type titanium peroxide dispersion liquid doped with silica and silver of example 2, and the coating film of sample 2 formed alone.
In the case of, even though the photocatalytic activity was the best, the water solution for forming a film of Example 2 was diluted on the amorphous titanium peroxide film formed using the water solution of Comparative Example 1. In the case of the sample 4 formed by laminating the coating film formed by using the anatase type titanium peroxide dispersion liquid, in the case of the sample corresponding to the present invention formed by using the coating liquid other than Example 2 It is needless to say that the photocatalytic activity is lower than that of the sample having the photocatalytic activity formed by using the water solution for film formation of the comparative example.

[0096]

EFFECTS OF THE INVENTION The water solution for forming a coating film of the present invention has a photocatalytic property and at the same time a highly conductive coating film having a surface resistance value of less than 10 ¹¹ Ω / □ is applied to a plate glass, a ceramic such as a tile, a metal plate or a plastic plate. Etc. can be formed on the surface of various substrates. Therefore, this coating can exhibit photocatalytic performance and high conductivity, and can decompose harmful substances such as microorganisms, antibacterial performance, antifouling performance of tiles or glass surfaces, antifogging performance, antistatic performance in copiers, etc. Various excellent functions such as electromagnetic shielding property can be exhibited.

As a result, it can be suitably used for applications requiring both high conductivity and photocatalytic ability, and examples of such applications include window glass, lenses, sensor protection glass, and plasma display masks. Further, the formed coating film has not only a photocatalytic ability, but also is transparent and hydrophilic, and is excellent in stability and adhesion. Therefore, a film having conductivity, antifouling property and antifogging property, and at the same time excellent in transparency can be formed stably and with strong bonding, and as a result, it is suitable for use in a substrate requiring visual performance such as window glass. .

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a method for producing a water solution for forming a coating film of the present invention.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) B01J 23/50 B01J 23/50 M 31/38 31/38 M 35/02 35/02 J B32B 7/02 104 B32B 7/02 104 C01G 23/04 C01G 23/04 C C09D 5/00 C09D 5/00 Z 5/24 5/24 7/12 7/12 (72) Inventor Yoshimitsu Matsui Ureshino, Fujitsu-gun, Saga Iwaya Kawauchi 425-2 Sustainable Technology Co., Ltd. Saga Research Institute F-term (reference) 4F100 AA21B AB02B AB17B AB18B AB21B AK01B AT00A BA02 BA03 BA07 BA10A BA10B EJ65C GB90 JC00 JG01B JG04B A01A0A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02A02 AA08 BA02B BA04B BA21B BA48A BC22B BC32B EA08 FB09 4H011 AA02 BA01 BB18 4J038 DC002 DJ012 HA186 HA201 HA246 HA256 HA326 HA366 MA08 NA02 NA05 NA20 PC02 PC03 PC08

Claims (8)

[Claims] 1. Containing anatase-type titanium oxide fine particles having a peroxo group and fine particles of a conductivity enhancing substance,
A water solution for forming a film, which has photocatalytic performance and conductivity for forming a film having a surface resistance value of less than 10 ¹¹ Ω / □. 2. A photocatalyst containing amorphous titanium oxide fine particles having a peroxo group and fine particles of a conductivity enhancing substance, which are subjected to heat treatment after film formation to form a film having a surface resistance value of less than 10 ¹¹ Ω / □. A water solution for forming a film having performance and conductivity. 3. The water solution for forming a film according to claim 1, wherein the conductivity improving substance is a salt of copper, tin, iron, zinc, indium or silver, or a conductive polymer. 4. A tetravalent titanium salt solution is reacted with a basic solution to form titanium hydroxide, which is peroxidized with an oxidizing agent and further heat-treated to obtain anatase-type peroxide. In any process of transferring to titanium oxide, fine particles of the conductivity improving substance are added to form a film containing the fine particles of the conductivity improving substance and the titanium oxide fine particles and having a surface resistance value of less than 10 ¹¹ Ω / □. For producing a water solution for forming a film, which has photocatalytic performance and electrical conductivity. 5. A method in which a salt solution of tetravalent titanium is reacted with a basic solution to form a hydroxide of titanium, and the hydroxide is peroxo-oxidized with an oxidizing agent to form amorphous titanium peroxide. In the process, a fine particle of the conductivity improving substance is added to contain the fine particle of the conductivity improving substance and the fine particles of titanium oxide, and a film having a surface resistance value of less than 10 ¹¹ Ω / □ is formed by heat treatment after film formation. A method for producing an aqueous solution for forming a film, which has photocatalytic performance and electrical conductivity for forming. 6. A substrate having a surface resistance value of 10 ¹¹ Ω /, which is formed on the substrate by the coating liquid according to claim 1.
A structure having a coating having a photocatalytic performance of less than □ and conductivity. 7. A photocatalytic performance and a conductivity of which surface resistance is less than 10 ¹¹ Ω / □, which is obtained by forming a film on the substrate using the water solution for forming a film according to claim 2, 3 or 5, and then subjecting the film to heat treatment. A structure having a coating with. 8. A primer layer having no photocatalytic performance is provided on a substrate.
A coating form according to any one of claims 1 to 3, further comprising:
The surface resistance value formed by the working water solution is 10 ¹¹Ω / □
Photodegradation resistance with a coating having full photocatalytic performance and conductivity
Structure that is resistant to light or deteriorated by light.