JP2001048538A - Titanium oxide-forming solution and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject solution useful as a titanium oxide coating agent or the like. SOLUTION: A method for producing this solution comprises the following procedure: a basic substance having hydroxyl group in an excess amount relative to that of the titanium is added to metallic titanium, or a solid titanium compound containing oxygen atom and/or hydrogen atom followed by addition of a hydrogen peroxide solution to form a solution, from which titanium ion, titanium-contg. ion and cations other than hydrogen ion are removed and an excess of the hydrogen peroxide solution in the solution is decomposed; the above operation is conducted plural times while keeping the solution at pH 3-10 until the total concentration of the above ions comes to <=1/2 of the titanium concentration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a titanium oxide forming solution and a method for producing the same, and more particularly, to a titanium oxide coating agent useful for forming a titanium oxide film on a substrate. Regarding the solution for forming an oxide and a method for producing the same, the solution for forming a titanium oxide obtained in the present invention is used for forming a protective film, a photocatalytic film, an ultraviolet cut film, a colored film, a dielectric film, a film type sensor, an oxidation film on various materials. It can be used for production of titanium sol and the like.

[0002]

2. Description of the Related Art Titanium oxide powder slurries, aqueous solutions of titanium chloride and titanium sulfate, sols prepared by hydrolysis of metal alkoxides, peroxotitanic acid solutions, peroxo groups Are known. The application method using titanium oxide powder is simple, but it is difficult to obtain a dense and good-adhesion film. In addition, since titanium oxide generally has a high synthesis temperature, it is limited to a substrate that can withstand firing at a high temperature. There is.

In order to obtain a dispersion liquid of fine particles of titanium oxide, an acid or an organic solvent is generally used.
An acid or an organic solvent may corrode the substrate itself to be applied, and a method of applying and baking an aqueous solution such as titanium chloride or titanium sulfate produces a substance having a problem in releasing to the atmosphere such as a halogen compound. In addition, the firing temperature needs to be several hundred degrees or more.

On the other hand, titanium oxide sols prepared by the sol-gel method can be applied or impregnated, can be applied over a large area, can be synthesized at low temperatures, and have many industrial advantages. However, titanium tetraisopropoxide, tetrabutyl titanate, etc. It is necessary to apply the organic metal by using the above organic metal, and there is a problem that the raw material is chemically unstable, is easily affected by temperature and atmosphere, and is difficult to handle, and further, these organic metal compounds are expensive.

In addition, the sol-gel method requires heating at 400 ° C. or higher to remove by baking since the raw material sol contains an acid or an organic substance, and is unsuitable for materials which are easily attacked by acid. Then it was easy to become porous. In addition, the sol-gel method needs to deal with the problem of corrosion of the substrate and the treatment of waste gas, as in the method using a chloride or the like as a raw material. Furthermore, if left at room temperature for several days, gelation or precipitation may occur, making it difficult to store for a long period of time. There was a problem with the use.

Further, the peroxotitanic acid solution and the anatase sol obtained by heat-treating the peroxotitanic acid solution can form an adherent coating film even at a low temperature, and cause little corrosion of the substrate and generation of harmful gases. It is known that it is excellent as a coating agent for titanium oxide.
However, the peroxotitanic acid solution was unstable, so that the synthesis conditions were limited. For example, JP-A-62-2
Japanese Patent No. 52319 discloses that in order to produce a high-purity titanium oxide film, a hydrogen peroxide solution is directly added to titanium hydride or alkoxytitanium to dissolve it, and finally a liquid containing titanium peroxide is prepared. A method of manufacture is described. However, titanium hydride or alkoxytitanium lacks chemical stability and is expensive, and when hydrogen peroxide water is applied, a considerable exothermic reaction occurs, resulting in an adverse effect such as abnormal thickening and white turbidity. there were. Therefore, when mass production is performed commercially, cooling cannot be performed sufficiently, so that peroxotitanic acid is polymerized and becomes very thick, and particles may grow to the extent that light transmission is interrupted and turbidity may occur. Therefore, there is a problem that the adhesion and the density of the coating film are reduced, and therefore, there is a problem that only a small amount can be manufactured.

JP-A-63-35419 and JP-A-1-224220 disclose titanyl ion hydrogen peroxide complexes prepared by adding aqueous hydrogen peroxide to a titanium hydroxide gel or sol. Alternatively, a method for producing an aqueous solution of titanic acid is described. However, if a hydrogen peroxide solution is directly added to titanium hydroxide, peroxo-formation and solution-formation occur at the same time, so there is a problem that heat generation is large and the particles grow and become cloudy due to thickening and polymerization. In this method, as in the other methods, when the production amount is large, it is difficult to adjust the temperature by cooling, and the solution may be thickened or clouded.

[0008] Further, since the peroxotitanic acid aqueous solution cannot be completely dissolved unless impurities are sufficiently removed, a titanium hydrate which is a gel or sol of titanium hydroxide produced in the process is not obtained. The precipitate must be thoroughly washed. A gel or sol of titanium hydrate such as titanium hydroxide is produced by adding a basic substance such as ammonia to an aqueous solution such as titanium chloride or titanium sulfate. Since precipitation of titanium occurs, cations such as ammonium ions and anions such as chlorine ions serving as impurities are taken in by adsorption or the like.

In particular, when the residual amount of anionic impurities such as chloride ions and sulfate ions is large, the polymerization of peroxotitanic acid generated after the addition of aqueous hydrogen peroxide is promoted, and a transparent aqueous solution may not be obtained. Or had caused thickening. In addition, impurity ions adsorbed on titanium hydrate are repeatedly washed with purified water to reduce the concentration,
A transparent solution of peroxotitanic acid can be prepared by the action of aqueous hydrogen peroxide, but if the concentration of impurities is low, it is difficult for titanium hydrate to precipitate, so that a very long time was required for cleaning. In addition, the present inventors have disclosed a patent
No. 875993 and Japanese Patent No. 2938376 propose liquids for forming a titania film. However, compared to these methods, the production method is easier and a stable titania film having excellent properties even when produced in large quantities. There was a need to provide a forming liquid.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a titanium oxide forming solution used for a titanium oxide coating agent and the like and a method for producing the same. It is an object of the present invention to provide a stable solution for forming a titanium oxide, which solves the problems of the production method for titanium oxide, and a new method for producing a dispersion sol of anatase fine particles obtained thereby. It is another object of the present invention to provide a production method in which a solution is promoted by adjusting impurity ions in a reaction process from a raw material to a titanium oxide forming solution.

[0011]

The present invention relates to a method for forming a titanium oxide, comprising the steps of: adding a titanium metal or a solid titanium compound containing at least one of oxygen and hydrogen to a titanium oxide solution; And adding a basic substance having an excess of hydroxyl groups, and further adding a hydrogen peroxide solution to form a solution. The concentration of cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution is 1/1/1 of the titanium concentration. It is a solution for forming a titanium oxide of 2 or less. Further, in the method for producing a solution for forming a titanium oxide, the basic titanium compound having an excess hydroxyl group with respect to the amount of titanium may be added to the titanium metal or the solid titanium compound containing at least one of oxygen and hydrogen. The process of removing the cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution formed by adding the substance and further adding the hydrogen peroxide solution and decomposing the excess hydrogen peroxide solution is performed by adjusting the pH of the solution to 3 to 3.
This is a method for producing a titanium oxide forming solution, which is performed a plurality of times while holding at 10. The method for producing a solution for forming a titanium oxide as described above, wherein the solid titanium compound is a titanium hydrate formed by adding a basic substance to the titanium compound. This is a method for producing a titanium oxide-forming solution, wherein a basic substance having a hydroxyl group amount twice or more the amount of titanium is added.

In the method for producing a solution for forming a titanium oxide, the method comprises the steps of: adding titanium metal or a solid titanium compound containing at least one of oxygen and hydrogen;
After adding a basic substance having a hydroxyl group in excess with respect to the amount of titanium and precipitating and separating the titanium compound, washing and removing cations other than titanium ions, titanium-containing ions and hydrogen ions, hydrogen peroxide This is a method for producing a titanium oxide forming solution that is dissolved by adding water.

The concentration of cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution is 1% of the titanium concentration.
/ 2 or less. This is the method for producing a titanium oxide forming solution described above, wherein the solution contains peroxotitanium.

[0014] In the method for producing a titanium oxide coating composition, the metal titanium or the solid titanium compound containing at least one of oxygen and hydrogen has an excessive hydroxyl group with respect to the amount of titanium. The removal of titanium ions, titanium-containing ions and cations other than hydrogen ions and the decomposition of excess hydrogen peroxide in the solution formed by adding a basic substance and further adding aqueous hydrogen peroxide are performed by p
By performing H several times while maintaining H at 3 to 10,
A method for producing a titanium oxide coating composition in which the concentration of cations other than titanium ions, titanium-containing ions and hydrogen ions is reduced to half or less of the titanium concentration, and then heat-treated at a temperature of 80 ° C. or more to precipitate anatase particles. It is.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention uses a specific raw material as a raw material for producing a titanium compound, and combines a solution of a novel titanium compound with a step of forming a titanium oxide in a solution to obtain a characteristic. It is intended to provide a solution for forming a titanium oxide which can be used for the formation of a titanium oxide and the like, and a method for producing the same. That is, a solution formed after adding an excess of a basic substance having a hydroxyl group with respect to the amount of titanium to a metal titanium or a titanium compound containing at least one of oxygen and hydrogen, and further reacting and dissolving with a hydrogen peroxide solution. Thus, by lowering the basic substance to a predetermined concentration or less without lowering the yield of titanium, a titanium oxide forming solution suitable as a titanium oxide coating agent having a stable peroxo group is obtained. It is found that it can be done.

In particular, at least one of titanium, hydrogen, and oxygen, such as titanium metal, titanium hydride, and titanium oxide, which has not conventionally been generally used as a raw material of a dispersant comprising a titanium oxide coating agent. It is an object of the present invention to provide a method for producing an aqueous solution of peroxotitanic acid which is useful as a stable titanium oxide coating agent or the like by using a compound of a seed and titanium.

A solution obtained by adding a basic substance and aqueous hydrogen peroxide to titanium, titanium hydride, titanium oxide, or the like and dissolving the same is based on the type and amount of the basic substance used for dissolution or the addition of the aqueous hydrogen peroxide. Although it varies depending on the amount, it remains a transparent solution for several minutes to several days after the solution is generated, but as the time elapses, the solution becomes cloudy or gels and becomes unstable. . In addition, it can be stored by cooling, but there is a problem in long-term storage. Focusing on the cause of the instability of such a titanium-containing solution being the remaining basic substance and hydrogen peroxide, while removing the basic substance to a predetermined concentration or less,
It is intended to obtain a stable titanium-containing compound by decomposing hydrogen peroxide.

Titanium dissolved in a titanium-containing solution prepared by adding an excess of a basic substance and hydrogen peroxide to titanium is present in the form of an anion composed of a complex having a hydroxyl group bonded thereto. Therefore, if these substances are removed after adding substances that exchange or supplement cations such as cation exchange resin and zeolite in the solution, the dissolved titanium is present in the solution without affecting the titanium. Cations derived from basic substances can be removed.

However, when cations derived from a basic substance are removed by a cation exchange resin or the like, the pH of the solution changes due to ion exchange between cations derived from the basic substance and hydrogen ions. When the pH is lower than a certain value, titanium-containing ions such as peroxotitanate ions in the solution become cations such as titanium ions and are captured by the cation exchange resin, so that titanium in the solution is lost. Therefore, it is necessary to remove the cation derived from the basic substance in the solution at pH 3 or more, and more preferably at pH 4 or more.

In addition, it is necessary to decompose hydrogen peroxide excessively added to the solution. However, when hydrogen peroxide is rapidly decomposed, there are problems such as an increase in pH and precipitation of a dissolved titanium compound. Occurs. It is necessary not to raise the pH to 10 or more, and more preferably not to 9 or more. Therefore, in the method of the present invention, in order to maintain the pH of the solution in the process of removing the basic substance and the process of decomposing hydrogen peroxide within a predetermined range, the removal of cations derived from the basic substance and the removal of hydrogen peroxide are performed. It is characterized in that the decomposition is performed a plurality of times.

In the present invention, the concentration of the cation in the solution does not mean the concentration of the dissociated one in the solution, but the concentration of the cation measured in the analysis of the undissociated one or the coordinated one. Means the whole amount. Similarly, the titanium concentration means the total amount of titanium present in the solution, regardless of the form in which the titanium exists.

An example of a method for removing cations derived from basic substances and decomposing hydrogen peroxide will be described below. 1. Metallic titanium, or titanium and hydrogen, a titanium-containing solution obtained by adding a basic substance and aqueous hydrogen peroxide to a titanium compound containing at least one of oxygen,
A cation exchange resin is added, and the pH is maintained within a range of weak acid or neutral range of about 3 to 6 to remove cations derived from basic substances. 2. Then, the hydrogen peroxide is decomposed by leaving the titanium-containing solution as it is, stirring, irradiating with an ultrasonic wave, or performing a heat treatment.
The range is from H7 to H10. 3. Again, a small amount of a cation exchange resin is added to the titanium-containing solution and deionized in the same manner as in 1 above to remove weak acids having a pH of about 3 to 6 or cations derived from basic substances within a neutral range. The same processing is performed.

In the above steps, in the first step of removing the cations derived from the basic substance, the cations cannot be sufficiently removed because a large amount of hydrogen peroxide is present in the solution. , The pH is in the range of about 3 to 6,
It is preferably in the range of 6 to 6. In the subsequent hydrogen peroxide decomposition step, when a large amount of hydrogen peroxide is decomposed, a precipitate of hydrated peroxotitanium may be deposited, so that the decomposition of hydrogen peroxide is carried out at a pH in the range of about 7 to 9. It is necessary to do within.

Then, the subsequent removal of the cation derived from the basic substance and the decomposition of the hydrogen peroxide, the titanium in the titanium oxide forming solution is lost in the cation removal step, or the peroxotitanium forms a polymer. It is necessary to prevent precipitation from occurring. The concentration of the cation derived from the basic substance in the obtained titanium oxide forming solution is preferably lower than the titanium concentration, and more preferably less than half. With such a concentration, it can be stably present as a coating agent.

In the present invention, as a basic substance used for dissolving titanium or a titanium compound, aqueous ammonia, an aqueous alkali metal hydroxide solution, an aqueous tetraalkylammonium solution and the like can be used. When forming a coating film of titanium oxide by using as a coating agent, ammonia water which is easily removed by volatilization and decomposition, preferably does not contain a metal element such as tetraalkylammonium, particularly preferably ammonia water .

The amount of the basic substance used for dissolving titanium or the titanium compound is preferably at least twice, more preferably at least four times, the number of moles of titanium. In the case of a titanium compound containing no hydroxyl group, the amount is preferably 4 times or more, more preferably 6 times or more. Dissolution with a basic substance and aqueous hydrogen peroxide is possible at room temperature, but the reaction may be promoted by heating.

The titanium-containing substance used as the raw material of the titanium oxide forming solution is metallic titanium obtained from a titanium mineral or the like,
Alternatively, a titanium compound containing any one of hydrogen and oxygen can be used. However, a hydrogen peroxide solution is added to an aqueous solution of a soluble titanium compound such as titanium tetrachloride, and then a basic substance such as ammonia water is added. Those obtained by removing anions such as chloride ions from titanium hydrate, titanium oxide or the like obtained by the above method may be used. In the present invention, the removal of cations derived from a basic substance may be performed by a method such as electrodialysis using an ion exchange membrane, dialysis, or reverse osmosis, in addition to the method using a cation exchange resin or zeolite. .

A basic solution is added to titanium metal or a titanium-containing compound, and a hydrogen peroxide solution is further added to dissolve the target solution without performing operations such as precipitation from a titanium oxide forming solution. Not only the preparation method, but also a solution in which titanium or a titanium compound is dissolved is allowed to stand as it is or is heated to precipitate a titanium compound, and then washed to remove cations derived from a basic substance. After reducing the concentration to not more than the concentration of hydrogen peroxide, a solution for forming titanium oxide can be prepared by further applying a hydrogen peroxide solution.

The concentration of the cation derived from the basic substance in the titanium oxide forming solution prepared by the above method is less than half, preferably one quarter, of the titanium concentration.
A titanium oxide coating composition comprising an anatase sol in which anatase fine particles are dispersed can be prepared by heating to a temperature of 80 ° C. or higher after decationization or by heating under an autoclave under pressure.

Further, after the titanium compound is precipitated from the titanium oxide forming solution, the amount of the hydrogen peroxide solution added during the peroxo-forming step of the titanium compound in which the titanium compound is re-solved is hydrogen peroxide / titanium. Is required to be 1 or more, and below it, it is difficult to completely peroxotify,
Since decomposition may occur without the added aqueous hydrogen peroxide reacting, it is preferable to add the hydrogen peroxide / titanium ratio in excess of 1. The reaction temperature may be either normal temperature or heating. However, when a stable material such as an oxide is used as the raw material, a higher temperature allows the reaction to proceed faster. However, when the temperature is high, volatile basic substances such as ammonia easily escape, and the added hydrogen peroxide is easily decomposed, so that the raw material becomes cloudy, gels or precipitates before completely turning the solution into solution. May be generated. When a large amount of a basic substance is contained, titanium oxide such as anatase rarely crystallizes even if the reaction temperature is increased.
Preferably, the reaction is carried out at a temperature of not more than ℃. The reaction can be promoted by stirring.

The aqueous solution for forming a titanium oxide of the present invention can be applied to a substrate and then heated at less than 200 ° C. to form an amorphous titanium oxide film. Further, by heating to 200 ° C. or more, a crystalline and dense titanium oxide film can be manufactured. These films have excellent acid resistance and can be used as various corrosion-resistant coatings. Further, a dispersion of anatase sol prepared from the aqueous solution for forming a titanium oxide of the present invention can form a crystalline titania film only by coating, and thus is useful as a coating agent for a material that cannot be subjected to heat treatment. Further, the dispersion liquid of anatase sol can be used as a coating agent by mixing with a stable titanium oxide forming solution of the present invention at an arbitrary ratio, thereby forming an anatase film having excellent adhesion. it can. Further, after applying the titanium oxide forming solution of the present invention onto a substrate such as a synthetic resin using both the stable titanium oxide forming solution and the anatase sol dispersion, the anatase sol dispersion Is applied to form a layer, the photocatalytic action of the titanium oxide layer on the surface causes decomposition or the like of the organic substance of the substrate to occur, thereby preventing the applied titanium oxide layer from peeling off from the substrate.

The solution for forming a titanium oxide of the present invention can be used for the purpose of forming a protective film or a photocatalyst layer, and a film having a high density and good adhesion can be obtained at a relatively low temperature. Further, the titanium oxide fine particles obtained from the titanium oxide forming solution of the present invention are excellent in dispersibility, and are mixed with various solid fine particles in advance, and then dispersed by an ultrasonic dispersing device, a ball mill or the like, and then coated. It is also possible to produce a composite in which other fine particles are supported or dispersed in a titanium oxide film obtained by drying and firing.
In addition, as a substrate to be applied, ceramics, ceramics,
Metals, plastics, fibers, building materials, and the like can be used, and the inside of the porous body and the surface treatment of the powder can be performed.

[0033]

The present invention will be described below with reference to examples and comparative examples. Example 1 Titanium dioxide was used as a titanium raw material. 0.8% titanium dioxide (Titanium dioxide P25 manufactured by Nippon Aerosil Co., Ltd.)
g, and 15 ml of a two-fold dilution of 25% by weight ammonia water was added.
and stirred with distilled water to make 100 ml.
The solution was left standing at 2 ° C. for 2 days to obtain a yellow transparent solution. The titanium concentration is 0.1 mol / l and the ammonium concentration is 1.1
mol / l.

Next, an H ⁺ -substituted cation exchange resin washed with distilled water (Amberlite IR118 manufactured by Organo)
30 g was gradually added to the obtained solution, and the mixture was stirred.
H5. After the added cation exchange resin was separated, it was irradiated with ultrasonic waves to decompose hydrogen peroxide until the pH reached 8. The decomposition of hydrogen peroxide can be confirmed by the generation of bubbles from the liquid.

Further, after the pH of the solution was adjusted to 5 by the same operation as the cation removal with the cation exchange resin,
The operations of decomposing hydrogen peroxide and removing cations with a cation exchange resin were performed twice, respectively, to obtain an aqueous solution for forming a titanium oxide having a pH of 5. The ammonium concentration in the obtained solution was 0.01 mol / l.

A powder obtained by drying the obtained solution at 25 ° C. was subjected to an X-ray diffractometer (RAD-B manufactured by Rigaku Corporation) using a copper target at an acceleration voltage of 30 kV and a current of 15 kV.
The measurement was performed under mA measurement conditions, and the results are shown in FIG. The obtained liquid was amorphous. The powder dried at 25 ° C. was mixed with potassium bromide to form tablets, and the powder was measured by a potassium bromide tablet method using a Fourier transform infrared absorption spectrometer (FT / IR-5300 manufactured by JASCO Corporation) by a transmission method. The result is shown in FIG. 900cm ^-1
Absorption was observed in the vicinity, and it was confirmed that a peroxo group was present. In addition, no precipitate was deposited even after standing at 25 ° C. for 30 days, and there was no change in the properties of the solution.

In all Examples and Comparative Examples, the titanium concentration and the ammonium concentration were measured by the following measuring methods. (Measurement method of titanium concentration) An arbitrary amount of a sample is sampled, diluted 200 times with distilled water, and, using an ICP emission spectrophotometer (ICPS-2000 manufactured by Shimadzu Corporation), a titanium standard solution is used to obtain (Wako Pure Chemical Industries, Ltd.) The concentration of titanium was measured from a calibration curve prepared from standard solutions having concentrations of 10 ppm, 20 ppm, and 40 ppm prepared from the product (concentration: 1000 ppm).

(Method for Measuring Ammonium Concentration) An arbitrary amount of a sample is sampled, and if hydrogen peroxide is contained, it is completely decomposed and then diluted 10-fold, and 1 ml thereof is sampled in a container and distilled. 20 ml of water and 1 ml of an aqueous solution of zinc sulfate having a concentration of 0.35 mol / l were added, and an alkaline solution obtained by dissolving 30 g of sodium hydroxide and 25 g of sodium carbonate in 200 ml of distilled water was added to adjust the pH to 10.5. Next, 10 ml of a 1.3 mol / l sodium phenolate solution and 1 ml of a 0.15 mol / l disodium ethylenediaminetetraacetate solution were added, followed by stirring, 5 ml of a 1% by volume aqueous sodium hypochlorite solution was added, and distilled water was added. The mixture was stirred at 50 ml and filtered after 30 minutes. The absorbance at 630 nm of the obtained filtrate was measured with a spectrophotometer (UV-2100 manufactured by Shimadzu Corporation). Also,
A standard solution was prepared by dissolving and diluting ammonium chloride (special grade reagent), and a standard curve was prepared by measurement in the same manner as the test solution to determine the concentration of the test solution.

Example 2 Metallic titanium was used as a titanium raw material. 0.48 g of titanium metal powder (metal titanium powder manufactured by Wako Pure Chemical Industries) is weighed,
7 ml of a 2 times diluted solution of 25% by weight aqueous ammonia was added, 20 ml of 30% by weight aqueous hydrogen peroxide was added, and the mixture was stirred with distilled water to 100 ml. Was obtained. The titanium concentration is 0.1 mol / l and the ammonium concentration is 0.6 mol / l.
l.

Next, an H ⁺ -substituted cation exchange resin washed with distilled water (Amberlite IR118 manufactured by Organo)
And slowly stirred into the resulting solution to obtain pH
After the separation of the cation exchange resin added when reaching 5,
Decompose hydrogen peroxide by irradiating ultrasonic waves, and when the pH becomes 8, add 5 g of cation exchange resin again and p
H was set to 4.

Further, the operation of decomposing hydrogen peroxide and the operation of removing cations with a cation exchange resin were performed twice, respectively, to obtain an aqueous solution for forming a titanium oxide having a pH of 5. The titanium concentration was 0.1 mol / l and the ammonium concentration was 0.01 mol / l.

The powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer to find that it was amorphous. Further, when measured by a Fourier transform infrared absorption spectrum measuring apparatus in the same manner as in Example 1, absorption was observed at around 900 cm ^-1 , confirming that a peroxo group was present.

Example 3 Titanium tetrachloride was used as a titanium raw material. To a solution obtained by diluting 5 ml of a 60% by weight aqueous solution of titanium tetrachloride to 500 ml with distilled water, a 10-fold diluted solution of 25% by weight aqueous ammonia was dropped to adjust the pH to 7, and a white gel-like titanium hydroxide was precipitated. After filtration and washing, the filtration residue was adjusted to a total volume of 150 ml with distilled water. Next, 25 ml of a 4-fold diluted solution of 25% by weight aqueous ammonia and 20 ml of 30% by weight aqueous hydrogen peroxide and distilled water were added and left to stand. After 12 hours, 250 ml of a yellow liquid containing titanium was obtained. The titanium concentration of the obtained titanium-containing solution was 0.1 mol / l, the ammonium concentration was 0.38 mol / l, and the chlorine concentration was 0.1 mol / l.
It was 0086 mol / l.

Next, 50 g of an H ⁺ -substituted cation exchange resin (Amberlite IR118 manufactured by Organo) washed with distilled water was added to the obtained solution, and left for 1 hour to remove ammonium ions. The ion-exchange resin was separated and removed, and 10 ml of a 30% by weight hydrogen peroxide solution was added while keeping the solution at 7 ° C. to obtain a yellow transparent aqueous peroxotitanic acid solution. The ammonium concentration in this solution was 0.011 mol / l.

The powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer to find that it was amorphous. Further, when measured by a Fourier transform infrared absorption spectrum measuring apparatus in the same manner as in Example 1, absorption was observed at around 900 cm ^-1 , confirming that a peroxo group was present.

Example 4 Titanium tetrachloride was used as a titanium raw material. To a solution obtained by diluting 5 ml of a 60% by weight aqueous solution of titanium tetrachloride to 500 ml with distilled water, a 10-fold diluted solution of 25% by weight aqueous ammonia was dropped to adjust the pH to 7, and a white gel-like titanium hydroxide was precipitated. After filtration and washing, the residue was made up to a total volume of 150 ml with distilled water, and the solution was cooled to 10 ° C. or lower with ice water, and 20 ml of a 30% by weight hydrogen peroxide solution was added thereto.
The reaction was carried out for 2 hours to obtain a yellow translucent solution for forming a titanium oxide.

An anion exchange resin (Amberlite IRA410 manufactured by Organo) was added to the obtained titanium oxide forming solution.
It was washed after 1 hour with 1N sodium hydroxide, OH ^- after 3 hours left to put 30g those with substituted, concentration after separation of the anion exchange resin 25 wt%
25 ml of a 4 times dilution of aqueous ammonia and 10 ml of a 30% by weight aqueous solution of hydrogen peroxide were added and allowed to stand. After 12 hours, 250 ml of a yellow liquid containing titanium was obtained. Titanium concentration 0.1mol / l, ammonium concentration 0.39mo
l / l and the chlorine concentration were 0.0039 mol / l.

Next, an H ⁺ -substituted cation exchange resin washed with distilled water (Amberlite IR118 manufactured by Organo)
50 g was put into the obtained solution and allowed to stand for 1 hour to remove the remaining ammonium ions. Then, the added cation exchange resin was separated and removed.
10% hydrogen peroxide at a concentration of 30% by weight while maintaining
1 to give a clear yellow solution. The ammonium concentration in the solution was 0.013 mol / l.

The powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer to find that it was amorphous. Further, when measured by a Fourier transform infrared absorption spectrum measuring apparatus in the same manner as in Example 1, absorption was observed at around 900 cm ^-1 , confirming that a peroxo group was present.

Example 5 Titanium tetrachloride was used as a titanium raw material. A solution obtained by diluting 5 ml of a 60% by weight aqueous solution of titanium tetrachloride to 500 ml with distilled water and 20 ml of a 30% by weight aqueous hydrogen peroxide solution were added.
The mixture was stirred to produce a brown transparent liquid, and a 10-fold diluted solution of 25% by weight ammonia water was added dropwise to this solution to add p
H was set to 7 to prepare a yellow transparent solution, which was allowed to stand at 25 ° C. for 24 hours to precipitate a yellow precipitate. After washing by filtration, the filtration residue was made up to 150 ml with distilled water.

Next, an anion exchange resin (Amberlite IRA41 manufactured by Organo) was added to the obtained titanium compound dispersion.
0) and washed after 1 hour with 1N sodium hydroxide, OH ^- after left to put 30g which was substituted 30 minutes, separate the added anion exchange resin using a synthetic resin net To remove chlorine ions, and then add 1
80 ml, 25 ml of a 4 times diluted ammonia water having a concentration of 25% by weight, 20 ml of a hydrogen peroxide solution having a concentration of 30% by weight, and distilled water were added thereto. After 12 hours, 250 ml of a transparent yellow liquid of a titanium compound was obtained. The titanium concentration of the obtained solution was 0.1 mol / l, the ammonium concentration was 0.41 mol / l, and the chlorine concentration was 0.005 m.
ol / l.

Next, 50 g of an H ⁺ -substituted cation exchange resin (Amberlite IR118, manufactured by Organo) washed with distilled water was added to the obtained solution, and left for 1 hour to remove ammonium ions. The ion-exchange resin was separated and removed, and the solution was cooled and kept at 7 ° C., and 10 ml of a 30% by weight hydrogen peroxide solution was added to obtain a yellow transparent solution. The ammonium ion concentration in this solution was 0.011 mol / l.

The powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer to find that it was amorphous. Further, when measured by a Fourier transform infrared absorption spectrum measuring apparatus in the same manner as in Example 1, absorption was observed at around 900 cm ^-1 , confirming that a peroxo group was present.

Example 6 50 ml of the liquid obtained in Example 2 was sealed in a glass container and heated at 100 ° C. for 5 hours to obtain a pale yellow translucent liquid. The powder obtained by drying this liquid was converted into X in the same manner as in Example 1.
Examination by a line diffraction confirmed that crystalline anatase was generated, and that the obtained liquid was an anatase sol.

Example 7 Metallic titanium was used as a titanium raw material. 0.48 g of titanium metal powder (manufactured by Wako Pure Chemical Industries) was weighed into four containers, and five, ten, and fifteen ml of a four-fold dilution of 25% by weight ammonia water was added to three containers. ,
Further, to all the containers, 40 ml of a 30% by weight aqueous hydrogen peroxide solution and distilled water were added to stir to 100 ml, followed by stirring at 25 ° C. for 20 hours.

The titanium concentration was 0.1 mol / l, and the ammonium concentrations were 0, 0.18, 0.37, and 0.55, respectively.
mol / l. Ammonium concentration 0.18mo
Samples of 1 / l or less could not be completely dissolved, and slightly insoluble matter remained. In the case of 0.37 mol / l or more, it was completely transparent and dissolved.

In the obtained solution, H ⁺ washed with distilled water was added.
Substitution type cation exchange resin (Amberlite I manufactured by Organo)
30 g of R118) was gradually added thereto, and the mixture was stirred to adjust the pH to 5. Next, after the added cation exchange resin was separated, ultrasonic waves were irradiated by an ultrasonic irradiation device to decompose hydrogen peroxide, and the pH increased with the decomposition of hydrogen peroxide. When the pH reaches 8, cation exchange resin 5g again
Was added and stirred to adjust the pH to 5, and then the cation exchange resin was separated. Next, the decomposition of hydrogen peroxide by ultrasonic irradiation and the treatment with a cation exchange resin were repeated twice to obtain p.
A clear yellow aqueous solution of H5 was obtained. The ammonium concentration in the obtained liquid was 0.01 mol / l.

When the obtained solution was dried in the same manner as in Example 1, the powder obtained was measured by an X-ray diffractometer to find that it was amorphous. Further, when measured by a Fourier transform infrared absorption spectrum measuring apparatus in the same manner as in Example 1, absorption was observed at around 900 cm ^-1 , confirming that a peroxo group was present.

Example 8 Titanium dioxide was used as a titanium raw material. 0.8 g of titanium dioxide (titanium dioxide P25, manufactured by Nippon Aerosil Co., Ltd.) was weighed into each of three containers, and 4, 10, and 15 ml of a 4-fold diluted solution of 25% by weight ammonia water were added thereto, and a 30% by weight excess was added. Hydrogen oxide water (40 ml) was added, and the mixture was stirred at 100 ml with distilled water and stirred. Next, the mixture was heated at 60 ° C. for 5 minutes and then left at 25 ° C. for 30 hours to dissolve.
The titanium concentration was 0.1 mol / l and the ammonium concentrations were 0.18, 0.37, and 0.55 mol / l, respectively. A sample having an ammonium ion concentration of 0.37 mol / l or less cannot be completely dissolved, and a sample without addition of ammonia hardly dissolves titanium oxide powder,
Only a white opaque suspension was obtained.

In the obtained solution, H ⁺ washed with distilled water was added.
Substitution type cation exchange resin (Amberlite I manufactured by Organo)
Then, 30 g of R118) was gradually added and stirred to adjust the pH to 5, and then the cation exchange resin was separated. Next, ultrasonic waves were irradiated by an ultrasonic irradiation device to partially decompose hydrogen peroxide. When the pH increased with the decomposition of hydrogen peroxide, and the pH reached 8, the cation exchange resin was again charged with 5 g of cation exchange resin and stirred to adjust the pH to 5, and then the cation exchange resin was separated. Next, the decomposition of hydrogen peroxide by ultrasonic irradiation and the treatment with a cation exchange resin were repeated twice to obtain a yellow transparent aqueous solution having a pH of 5. The ammonium concentration in the obtained liquid was 0.01 mol / l.

Example 9 A 20 ml portion of the transparent solution obtained in the same manner as in Example 2 was fractionated, and aqueous ammonia was added to adjust the ammonium ion concentration in the solution to 0.0136, 0.021, and 0.1. 028
4, 0.0358, 0.0423 mol / l and 0.1.
055 mol / l, put in a closed container
Heat at 00 ° C. for 6 hours.

The solution obtained by drying this solution at 25 ° C. was measured for its powder by an X-ray diffractometer in the same manner as in Example 1. The result is shown in FIG. FIG. 4 shows a Fourier transform infrared absorption spectrum of the same powder measured in the same manner as in Example 1.
Those having an ammonium concentration of 0.0284 mol / l or more were amorphous as a result of X-ray diffraction, and were examined by Fourier transform infrared spectroscopy. As a result, absorption was observed at around 900 cm ⁻¹ , and a peroxo group was present. I was able to confirm that.

On the other hand, those having a concentration of 0.021 mol / l or less contained anatase crystals and were found to be in a sol state as a result of X-ray diffraction. That is, anatase sol was obtained only when the ammonium concentration was lower than the titanium concentration. On the other hand, in the case of adding only ammonia without heat treatment at 100 ° C., 0.0423 mol / l
The following materials were transparent at room temperature for one month or more and remained unchanged, while those having a concentration of 0.055 mol / l were turbid and unstable. Also, a stable aqueous peroxotitanic acid solution was obtained only when the ammonium concentration was 1/2 or less of the titanium concentration, and there was no long-term stability at higher concentrations.

Example 10 A titanium concentration of 0.1 mol obtained in the same manner as in Example 2.
/ L of the yellow transparent solution was heated at 70 ° C for 3 hours to precipitate a yellow gel precipitate. After washing this gel with distilled water,
The solution was made up to 80 ml with distilled water, cooled and kept at 7 ° C., and 20 ml of a 30% by weight aqueous hydrogen peroxide solution was added to obtain a yellow and transparent titanium compound solution. The ammonium concentration in this solution was 0.02 mol / l.

The powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer to find that it was amorphous. Further, when measured by a Fourier transform infrared absorption spectrum measuring apparatus in the same manner as in Example 1, absorption was observed at around 900 cm ^-1 , confirming that a peroxo group was present.

Example 11 Metal titanium was used as a titanium raw material. 0.48 g of metal titanium powder (metal titanium powder manufactured by Wako Pure Chemical Industries) was collected,
7 ml of a 2 times diluted solution of 25% by weight aqueous ammonia was added, 20 ml of 30% by weight aqueous hydrogen peroxide was added, and the mixture was stirred with distilled water to 100 ml. Was obtained. Titanium concentration is 0.1 mol / l, ammonium ion concentration is 0.6 m
ol / l.

Next, 30 g of an H ⁺ -substituted cation exchange resin (Amberlite IR118 manufactured by Organo) was gradually charged into the obtained solution, stirred, and when the pH reached 5, the added cation exchange resin was separated. Thereafter, ultrasonic irradiation was performed to decompose hydrogen peroxide to obtain a solution 1. Next, 2 g of the cation exchange resin was added to the solution 1 again, and when the pH reached 5, the cation exchange resin was separated, followed by ultrasonic irradiation to decompose hydrogen peroxide to obtain a solution 2. Further, 2 g of the cation exchange resin was added to the solution 2, and when the pH reached 5, the ion exchange resin was separated and irradiated with ultrasonic waves to decompose hydrogen peroxide to obtain a solution 3.

Each solution was yellow and transparent, and the ammonium ion concentration was as follows: solution 1: 0.058 mol / l;
Solution 2: 0.043 mol / l, Solution 3: 0.020 m
ol / l. The solution 2 and the solution 3 did not change for one month or more, but the solution 1 became cloudy from the second day after standing at 25 ° C., and a solid substance precipitated.

Further, the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer to find that it was amorphous. Further, when measured by a Fourier transform infrared absorption spectrum measuring apparatus in the same manner as in Example 1, absorption was observed at around 900 cm ^-1 , confirming that a peroxo group was present.

Example 12 Metallic titanium was used as a titanium raw material. 0.48 g of titanium metal powder (metal titanium powder manufactured by Wako Pure Chemical Industries) is weighed,
50 g of 4 g of sodium hydroxide (special grade reagent, manufactured by Wako Pure Chemical Industries)
g of distilled water, 20 ml of 30 wt% hydrogen peroxide solution was added, and the mixture was stirred with distilled water to 100 ml. The mixture was allowed to stand at 25 ° C. for 15 hours to dissolve the yellow transparent solution. Obtained. The titanium concentration was 0.1 mol / l and the sodium concentration was 1 mol / l.

Next, 60 g of an H ⁺ -substituted cation exchange resin (Amberlite IR118 manufactured by Organo) was gradually introduced into the obtained solution, stirred, and when the pH reached 5, the ion exchange resin was separated. When sonication was performed to decompose hydrogen peroxide to reach pH 8, 4 g of the cation exchange resin was added again, and when the pH reached 5, the added cation exchange resin was separated. When the hydrogen oxide was decomposed to pH 8, the cation exchange resin was again charged and sonicated, and 4 g was charged to adjust the pH to 5. After the separation of the resin, ultrasonic treatment and treatment with a cation exchange resin were repeated three times to adjust the pH to 6, and a yellow transparent titanium oxide forming solution was obtained. The sodium ion concentration in this solution was 0.01 mol / l.

The powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer to find that the powder was amorphous. Further, when measured by a Fourier transform infrared absorption spectrum measuring apparatus in the same manner as in Example 1, absorption was observed at around 900 cm ^-1 , confirming that a peroxo group was present.

Example 13 and Comparative Example 1 Metallic titanium was used as a titanium raw material. 0.48 g of metal titanium powder (metal titanium powder manufactured by Wako Pure Chemical Industries) was collected,
7 ml of a 2 times diluted solution of 25% by weight aqueous ammonia was added, 20 ml of 30% by weight aqueous hydrogen peroxide was added, and the mixture was stirred with distilled water to 100 ml. Was obtained. The titanium concentration is 0.1 mol / l and the ammonium concentration is 0.6 mol / l.
l.

Then, after stirring while changing the input amount of the H ⁺ substituted cation exchange resin (Amberlite IR118 manufactured by Organo), the pH, titanium concentration, The ammonium ion concentration was measured, and the results are shown in Table 1. Hydrogen peroxide remained in all the samples and foaming continued, and after 3 days, the foaming stopped and the pH increased, and turbidity and precipitation occurred in all samples.

[0075]

Table 1 Cation 3 days later Exchange resin pH pH Titanium concentration Ammonium concentration Input amount (g) (mol / l) (mol / l) Sample 1 15 7 11 0.1 0.10 Sample 2 20 5 9 0.096 0.065 sample 3 25 47 0.094 0.058 sample 4 35 3.5 6 0.084 0.045 sample 5 45 3 4 0.055 0.033 sample 6 55 2.54 0.014 0. 017 Sample 7 65 2.5 4 0.004 0.011

Comparative Example 2 The titanium oxide forming solution prepared in Example 1 without performing the treatment with a cation exchange resin was left at 25 ° C. for 5 days to form a yellowish cloudy gel. The liquid obtained in Example 1 did not change even when left at room temperature for 30 days.

[0077]

According to the present invention, a basic substance in a titanium oxide forming solution dissolved by a basic substance and a hydrogen peroxide solution, using metal titanium or a compound containing only metal titanium and either hydrogen or oxygen as a raw material. By removing the derived cations and hydrogen peroxide stepwise, the titanium oxide forming solution can be stabilized, and a coating material for forming titanium oxide having excellent properties can be produced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the result of X-ray diffraction of a powder obtained by drying a titanium oxide forming solution obtained in Example 1.

FIG. 2 is a view for explaining the measurement results of a titanium oxide forming solution obtained in Example 1 by a Fourier transform infrared absorption spectrum measuring apparatus.

FIG. 3 is a diagram illustrating an X-ray diffraction result of a powder obtained by drying a titanium oxide forming solution obtained in Example 9.

FIG. 4 is a diagram illustrating the results of measurement of a titanium oxide forming solution obtained in Example 9 by a Fourier transform infrared absorption spectrum measuring apparatus.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission Date] April 7, 2000 (200.4.7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

[0011]

SUMMARY OF THE INVENTION The present invention relates to a method for forming a titanium oxide, which comprises adding a solid titanium compound comprising metal titanium, titanium oxide or titanium hydrate to a titanium oxide in an excess amount relative to the amount of titanium. A basic substance having a hydroxyl group is added, and a hydrogen peroxide solution is further added to form a solution. The concentration of cations other than titanium ions, titanium-containing ions, and hydrogen ions in the solution is １ ／ or less of the titanium concentration. This is a titanium oxide forming solution. Further, in the method for producing a solution for forming a titanium oxide, metallic titanium, titanium oxide, or a solid titanium compound comprising titanium hydrate, a basic substance having an excess of hydroxyl groups relative to the amount of titanium, Further, the pH of the solution was maintained at 3 to 10 in the steps of removing cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution formed by adding aqueous hydrogen peroxide and decomposing excess hydrogen peroxide water. This is a method for producing a titanium oxide forming solution that is performed a plurality of times in a state. The method for producing a solution for forming a titanium oxide as described above, wherein the solid titanium compound is a titanium hydrate formed by adding a basic substance to the titanium compound. This is a method for producing a titanium oxide-forming solution, wherein a basic substance having a hydroxyl group amount twice or more the amount of titanium is added.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

In the method for producing a solution for forming a titanium oxide, the solid titanium compound comprising titanium metal, titanium oxide or titanium hydrate may contain a basic substance having an excess of hydroxyl groups relative to the amount of titanium. And further hydrogen peroxide solution was added to form a solution, and the titanium compound was precipitated and separated, and then washed to remove cations other than titanium ions, titanium-containing ions and hydrogen ions, and then hydrogen peroxide solution was added. This is a method for producing a titanium oxide forming solution that dissolves in water.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

Further, in the method for producing a titanium oxide coating agent, a basic substance having an excess of hydroxyl groups with respect to the amount of titanium is added to a solid titanium compound comprising titanium metal, titanium oxide or titanium hydrate. In addition, the removal of titanium ions, titanium-containing ions, and cations other than hydrogen ions in the solution formed by further adding aqueous hydrogen peroxide and the decomposition of excess hydrogen peroxide are maintained at a pH of the solution of 3 to 10. By performing the heat treatment at a temperature of 80 ° C. or more after reducing the concentration of cations other than titanium ions, titanium-containing ions, and hydrogen ions to half or less of the titanium concentration, to precipitate anatase particles. This is a method for producing a titanium oxide coating agent.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction contents]

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention uses a specific raw material as a raw material for producing a titanium compound, and combines a solution of a novel titanium compound with a step of forming a titanium oxide in a solution to obtain a characteristic. It is intended to provide a solution for forming a titanium oxide which can be used for the formation of a titanium oxide and the like and a method for producing the same. That is, after adding a basic substance having a hydroxyl group in excess of the amount of titanium to a solid titanium compound composed of titanium metal, titanium oxide, or titanium hydrate, and further dissolving it with a hydrogen peroxide solution, From the resulting solution, by lowering the basic substance to a predetermined concentration or less without lowering the yield of titanium, a titanium oxide forming agent suitable as a titanium oxide coating agent having a stable peroxo group, etc. It has been found that a solution can be obtained.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

In particular, use of a solid titanium compound composed of titanium metal, titanium oxide, or titanium hydrate, which has not conventionally been generally used as a raw material of a dispersant composed of a titanium oxide coating agent. Accordingly, the present invention provides a method for producing an aqueous solution of peroxotitanic acid which is useful as a stable titanium oxide coating agent or the like.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction contents]

A solution obtained by adding a basic substance and aqueous hydrogen peroxide to titanium, titanium oxide, titanium hydrate, or the like and dissolving the same depends on the type and amount of the basic substance used for dissolution or the amount of aqueous hydrogen peroxide. Although it depends on the amount added, it remains a transparent solution for several minutes to several days after the solution is formed, but as the time elapses, the solution becomes cloudy or gels and becomes unstable. is there. In addition, it can be stored by cooling, but there is a problem in long-term storage. Focusing on the cause of the instability of such a titanium-containing solution being the remaining basic substance and hydrogen peroxide, while removing the basic substance to a predetermined concentration or less,
It is intended to obtain a stable titanium-containing compound by decomposing hydrogen peroxide.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0077

[Correction method] Change

[Correction contents]

[0077]

According to the present invention, a solid titanium compound comprising titanium metal, titanium oxide, or titanium hydrate is used as a raw material.
It is possible to stabilize the titanium oxide forming solution by gradually removing cations and hydrogen peroxide derived from the basic substance in the titanium oxide forming solution dissolved by the basic substance and the hydrogen peroxide solution. Thus, a coating agent for forming a titanium oxide having excellent characteristics can be produced.

[Procedure amendment 9]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4

Claims (8)

[Claims] In a titanium oxide forming solution, a basic titanium compound containing an excess of hydroxyl groups with respect to the amount of titanium is added to metallic titanium or a solid titanium compound containing at least one of oxygen and hydrogen. A solution obtained by adding a substance and further adding a hydrogen peroxide solution, and the concentration of cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution is not more than 1/2 of the concentration of titanium. Solution for forming titanium oxide. 2. A method for producing a solution for forming a titanium oxide, comprising: adding an excess of hydroxyl groups to the amount of titanium to metallic titanium or a solid titanium compound containing at least one of oxygen and hydrogen. Adding a basic substance having, and further removing hydrogen ions and adding cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution produced by adding hydrogen peroxide solution, and decomposing excess hydrogen peroxide solution, A plurality of times while maintaining the temperature at 3 to 10 to produce a titanium oxide forming solution. 3. The method for producing a solution for forming a titanium oxide according to claim 2, wherein the solid titanium compound is a titanium hydrate formed by adding a basic substance to the titanium compound. 4. The method for producing a solution for forming a titanium oxide according to claim 3, wherein a basic substance having a hydroxyl group amount twice or more the amount of titanium is added. 5. A method for producing a solution for forming a titanium oxide, wherein an excess of hydroxyl groups with respect to the amount of titanium is added to titanium metal or a solid titanium compound containing at least one of oxygen and hydrogen. After adding a basic substance and depositing and separating the titanium compound, washing and removing cations other than titanium ions, titanium-containing ions and hydrogen ions, hydrogen peroxide water is added and dissolved. Of producing a titanium oxide forming solution. 6. The solution according to claim 2, wherein the concentration of cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution is not more than の of the titanium concentration.
The method for producing a titanium oxide-forming solution according to any one of the above items. 7. The solution according to claim 2, wherein the solution contains peroxotitanium.
4. The method for producing a solution for forming a titanium oxide according to claim 1. 8. The method for producing a titanium oxide coating composition, wherein the metal titanium or the solid titanium compound containing at least one of oxygen and hydrogen has an excessive hydroxyl group with respect to the amount of titanium. Add a basic substance,
Removal of cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution formed by further adding hydrogen peroxide solution and decomposition of excess hydrogen peroxide solution while maintaining the pH of the solution at 3 to 10. A plurality of times to reduce the concentration of cations other than titanium ions, titanium-containing ions and hydrogen ions to half or less of the titanium concentration, and then heat-treat at a temperature of 80 ° C. or more to precipitate anatase particles. A method for producing a titanium oxide coating composition, characterized in that: