Titanium oxide-forming solution and its production

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a titanium oxide forming solution and a method for producing the same, and is particularly useful for a titanium oxide coating agent used for the purpose of forming a titanium oxide film on a substrate and the like. Regarding the production method, the titanium oxide forming solution obtained in the present invention is used for producing a protective film, a photocatalyst film, an ultraviolet cut film, a colored film, a dielectric film, a film type sensor, a titanium oxide sol, etc. for various materials. What you get.

【0002】

[Conventional technology]

Examples of the coating agent used for forming the titanium oxide film include titanium oxide powder slurry, an aqueous solution of titanium chloride and titanium sulfate, a sol prepared by hydrolyzing a metal alkoxide, a peroxotitanic acid solution, and anatase sol containing a peroxo group. It has been known. Although the coating method using titanium oxide powder is simple, it is difficult to obtain a dense and good-adhesive film, and 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.

【0003】

An acid or an organic solvent is generally used to obtain a dispersed liquid of fine particles of titanium oxide. Acids and organic solvents may corrode the substrate to be coated, and the method of coating and firing an aqueous solution of titanium chloride or titanium sulfate produces substances such as halogen compounds that have problems in being released into the atmosphere. At the same time, the firing temperature also requires several hundred degrees or more.

【0004】

On the other hand, titanium oxide sol produced by the sol-gel method can be coated and impregnated, can be coated over a large area, and can be synthesized at low temperature, and has many industrial advantages. However, organic metals such as titanium tetraisopropoxide and tetrabutyl titanate are available. There is also a problem that the raw material is chemically unstable, easily affected by temperature and atmosphere, and difficult to handle, and these organometallic compounds are expensive.

【0005】

In addition, since the sol-gel method contains acids and organic substances in the raw material sol, heating at 400 ° C or higher is required to remove it by firing, and it is not suitable for materials that are easily attacked by acid. It was easy to get quality. Further, in the sol-gel method, it is necessary to treat the problem of corrosion of the substrate and waste gas as in the method using 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. Impurities mixed from the substrate during coating cause gelation, etc., so on an industrial scale. There was a problem in using it.

【0006】

In addition, the anatase sol obtained by heat-treating the peroxotitanate solution and the peroxotitanate solution can form an adhesive coating film even at a low temperature, and since there is little corrosion of the substrate and generation of harmful gas, titanium oxidation It is known to be excellent as a coating agent for substances. However, the peroxotitanic acid solution was unstable, so that the synthetic conditions were limited. For example, Japanese Patent Application Laid-Open No. 62-252319 states that in order to prepare a high-purity titanium oxide film, hydrogen peroxide solution is directly added and dissolved in titanium hydride or alkoxytitanium, and finally peroxidation is performed. A method for producing a liquid containing titanium hydrogen peroxide is described. However, titanium hydride or alkoxytitanium lacks chemical stability and is expensive, and when hydrogen peroxide solution is applied, a considerable exothermic reaction occurs, which has the disadvantage of causing adverse effects such as abnormal thickening and clouding. there were. Therefore, in the case of commercial mass production, peroxotitanic acid may polymerize and become extremely thickened due to insufficient cooling, and particles may grow to the extent that light transmission is blocked, resulting in turbidity. Therefore, there is a problem that the adhesion and density of the coating film are lowered, and therefore, there is a problem that it can be manufactured only in small amounts.

【0007】

Further, in Japanese Patent Application Laid-Open No. 63-35419 and Japanese Patent Application Laid-Open No. 1-224220, a titanyl ion hydrogen peroxide complex or titanium acid prepared by adding a hydrogen peroxide solution to a titanium hydroxide gel or sol. A method for producing an aqueous solution of hydrogen peroxide is described. However, when hydrogen peroxide solution is directly added to titanium hydroxide, peroxolation and solution formation occur at the same time, so that heat generation is large, and there is a problem that particles may grow and become turbid due to thickening and polymerization. Similar to other methods, this method also makes it difficult to adjust the temperature by cooling when the production amount is large, and the solution may thicken or become cloudy.

【0008】

In addition, the peroxotitanic acid aqueous solution cannot be completely dissolved unless impurities are sufficiently removed. Therefore, a titanium hydrate precipitate, which is a titanium hydroxide gel or sol produced in the process, is produced. Thorough cleaning must be done. Gels or sols of titanium hydrates such as titanium hydroxide are produced by adding a basic substance such as ammonia to an aqueous solution such as titanium chloride or titanium sulfate. Since the precipitation of titanium occurs, cations such as ammonium ions and anions such as chlorine ions, which are impurities, are taken in by adsorption or the like.

【0009】

In particular, if the residual amount of anionic impurities such as chlorine ions and sulfate ions is large, the polymerization of peroxotitanic acid generated after the addition of hydrogen peroxide solution may be promoted, and a transparent aqueous solution may not be obtained. It was causing thickening. Further, the impurity ions adsorbed on the titanium hydrate can be repeatedly washed with purified water to reduce the concentration, and a hydrogen peroxide solution is allowed to act to prepare a transparent peroxotitanic acid solution, but the impurity concentration is high. When the amount was reduced, the titanium hydrate was less likely to precipitate, so that a very long time was required for washing. Further, the present inventors have proposed liquids for forming a titania film in Japanese Patent No. 287593 and Japanese Patent No. 2938376, but the manufacturing method is easier than these methods, and they are manufactured in large quantities. However, it has been required to provide a stable liquid for forming a titania film having excellent properties.

【0010】

[Problems to be Solved by the Invention]

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

【0011】

[Means for solving problems]

The present invention is a basic substance having an excess hydroxyl group with respect to the amount of titanium in a solid titanium compound containing metallic titanium or at least one of oxygen and hydrogen in a solution for forming titanium oxide. For forming titanium oxide, in which the concentration of cations other than titanium ions, titanium-containing ions and hydrogen ions in the solution is 1/2 or less of the titanium concentration. It is a solution. Further, in the method for producing a solution for forming a titanium oxide, a solid titanium compound containing at least one of metallic titanium or oxygen and hydrogen is basic with an excess hydroxyl group with respect to the amount of titanium. The pH of the solution was adjusted to 3 to 3 to remove the titanium ions, titanium-containing ions and cations other than hydrogen ions in the solution generated by adding the substance and further adding the hydrogen peroxide solution, and decomposing the excess hydrogen peroxide solution. This is a method for producing a solution for forming a titanium oxide, which is carried out a plurality of times while being held at 10. The method for producing a solution for forming a titanium oxide, wherein the solid titanium compound is a titanium hydrate produced by adding a basic substance to the titanium compound. This is the method for producing the above-mentioned titanium oxide forming solution, in which a basic substance having a hydroxyl group amount that is twice or more the amount of titanium is added.

【0012】

Further, in the method for producing a solution for forming a titanium oxide, a solid titanium compound containing at least one of metallic titanium, oxygen, and hydrogen has a basicity having an excess hydroxyl group with respect to the amount of titanium. A solution for forming a titanium oxide that is dissolved by adding a hydrogen peroxide solution after adding a substance to precipitate and separate the titanium compound and then washing it to remove cations other than titanium ions, titanium-containing ions and hydrogen ions. It is a manufacturing method.

【0013】

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

【0014】

Further, in the method for producing a titanium oxide coating agent, a basic substance having an excess hydroxyl group with respect to the amount of titanium in a solid titanium compound containing at least one of metallic titanium or oxygen and hydrogen. To remove titanium ions, titanium-containing ions and cations other than hydrogen ions and decompose excess hydrogen peroxide solution in the solution generated by adding hydrogen peroxide solution to 3 to 10 pH of the solution. By performing this multiple times while holding it, the concentration of cations other than titanium ions, titanium-containing ions and hydrogen ions is reduced to less than half of the titanium concentration, and then heat-treated at a temperature of 80 ° C or higher to anatase particles. This is a method for producing a titanium oxide coating agent that precipitates.

【0015】

BEST MODE FOR CARRYING OUT THE INVENTION

In the present invention, a specific raw material is used as a raw material for producing a titanium compound, and a titanium oxide having excellent characteristics is obtained by combining a solution of a novel titanium compound and a step of forming a titanium oxide in the solution. It provides a titanium oxide forming solution that can be used for forming and the like, and a method for producing the same. That is, a solution produced by adding a basic substance having an excess hydroxyl group to the amount of titanium to metallic titanium or a titanium compound containing at least one of oxygen and hydrogen, and further reacting with a hydrogen peroxide solution to dissolve the solution. Therefore, by reducing the basic substance to a predetermined concentration or less without lowering the yield of titanium, a solution for forming a titanium oxide suitable as a titanium oxide coating agent having a stable peroxo group can be obtained. I found that I could do it.

【0016】

In particular, at least one of titanium, hydrogen, and oxygen such as metallic titanium, titanium hydride, and titanium oxide, which have not been generally used as a raw material for a dispersant made of a titanium oxide coating agent, and titanium. By using the compound of the above, a method for producing an aqueous solution of peroxotitanium acid, which is useful as a stable titanium oxide coating agent or the like, is provided.

【0017】

The solution prepared by adding a basic substance and a hydrogen peroxide solution to titanium, titanium hydride, titanium oxide, etc. depends on the type and amount of the basic substance used for dissolution, or the amount of the hydrogen peroxide solution added. However, although the solution remains in a transparent state for several minutes to several days after the solution is formed, the solution becomes cloudy or gels with the passage of time and is unstable. In addition, although it can be stored by cooling, there is a problem in terms of long-term storage. Focusing on the fact that the cause of the instability of such a titanium-containing solution is the residual basic substance and hydrogen peroxide, the basic substance should be removed below a predetermined concentration and the hydrogen peroxide should be decomposed. To obtain a stable titanium-containing compound.

【0018】

Titanium dissolved in a titanium-containing solution prepared by adding an excess of basic substance and hydrogen peroxide to titanium exists in the form of an anion composed of a complex in which a hydroxyl group is bonded. Therefore, if these substances are removed after adding substances that exchange or supplement cations such as cation exchange resins and zeolites to the solution, they are present in the solution without affecting the dissolved titanium. It is possible to remove cations derived from basic substances.

【0019】

However, when cations derived from a basic substance are removed with a cation exchange resin or the like, the pH of the solution changes due to ion exchange between the cations derived from the basic substance and hydrogen ions. When the pH becomes smaller 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 cations derived from the basic substance in the solution at pH 3 or higher, and more preferably the pH is 4 or higher.

【0020】

Further, it is necessary to decompose hydrogen peroxide excessively added to the solution, but if hydrogen peroxide is rapidly decomposed, problems such as an increase in pH and precipitation of dissolved titanium compounds occur. It is necessary that the pH is not raised above 10 and more preferably not above 9. Therefore, in the method of the present invention, in order to keep 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 by performing disassembly in multiple times.

【0021】

In the present invention, the concentration of cations in the solution does not mean the concentration of dissociated substances in the solution, but means the total amount of those measured in the analysis of non-dissociated substances, coordinated substances, etc. To do. Similarly, the titanium concentration means the total amount of titanium present in the solution regardless of the form of existence in the solution.

【0022】

An example of a method for removing cations derived from a basic substance and decomposing hydrogen peroxide will be described below. 1. A cation exchange resin is added to a titanium-containing solution obtained by adding a basic substance and a hydrogen peroxide solution to a metallic titanium or a titanium compound containing at least one of titanium, hydrogen and oxygen, and pH 3 It is kept within the range of weak acid or neutral range of about 6 to remove cations derived from basic substances. 2. Next, the titanium-containing solution is left as it is, stirred, ultrasonically irradiated, or heat-treated to decompose hydrogen peroxide. At that time, the pH of the titanium-containing solution rises within the range of pH 7 to 10. To do. 3. Again, in the same manner as in 1 above, add a small amount of cation exchange resin to the titanium-containing solution to deionize, and remove cations derived from basic substances within a weak acid or neutral range of about pH 3 to 6. Continue the same processing as in 2.

【0023】

In the above steps, in the first step of removing cations derived from the first basic substance, since a large amount of hydrogen peroxide is present in the solution, the cations cannot be sufficiently removed, so that the pH is high. It is preferably in the range of about 3 to 6 and preferably in the range of 4 to 6. In the subsequent decomposition step of hydrogen peroxide, when a large amount of hydrogen peroxide is decomposed, a precipitate of peroxotitanium hydrate may be precipitated. Therefore, the decomposition of hydrogen peroxide has a pH in the range of about 7 to 9. It is necessary to do it within.

【0024】

Then, the subsequent removal of cations derived from basic substances and the decomposition of hydrogen peroxide are carried out, such as titanium in the titanium oxide forming solution being lost in the cation removal step, peroxotitanium forming a polymer and precipitation, etc. It is necessary to prevent the occurrence of. The concentration of cations derived from the basic substance in the obtained titanium oxide-forming solution is preferably less than the titanium concentration, and is preferably half or less. By setting such a concentration, it can be stably present as a coating agent.

【0025】

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

【0026】

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

【0027】

As the titanium-containing substance used as a raw material for the solution for forming a titanium oxide, metallic titanium obtained from titanium minerals or the like, or a titanium compound containing any one of hydrogen and oxygen can be used, but titanium tetrachloride and the like can be used. To remove anions such as chloride ions from titanium hydrate, titanium oxide, etc. obtained by adding a basic substance such as ammonia water after adding hydrogen peroxide solution to the aqueous solution of the soluble titanium compound of. You may use the one obtained by. In the present invention, the removal of cations derived from a basic substance may be carried out by a method such as electrodialysis, dialysis or reverse osmosis using an ion exchange membrane, in addition to the method using a cation exchange resin or zeolite. ..

【0028】

A method for producing a target solution from a solution for forming a titanium oxide obtained by adding a basic substance to metallic titanium or a titanium-containing compound and further adding a hydrogen peroxide solution to obtain a solution without performing an operation such as precipitation. Not only that, the solution in which titanium or the titanium compound is dissolved is left as it is, or it is heated to precipitate a precipitate of the titanium compound, and then washed to wash the cations derived from the basic substance to the desired concentration or less. It is also possible to prepare a solution for forming a titanium oxide by further allowing a hydrogen peroxide solution to act after reducing the amount to.

【0029】

Further, after decationizing the cation concentration derived from the basic substance in the titanium oxide forming solution prepared by the above method to 1/2 or less, preferably 1/4 or less of the titanium concentration, 80 A titanium oxide coating agent consisting of an anatase sol in which anatase fine particles are dispersed can be prepared by heating to a temperature of ° C or higher or by heat-treating under pressure in an autoclave.

【0030】

In addition, the ratio of hydrogen peroxide / titanium is the amount of hydrogen peroxide solution added in the process of peroxodisulfurication of the titanium compound in which the titanium compound is precipitated again from the titanium oxide forming solution. If 1 or more is required, and if it is less than 1, it is difficult to completely peroxoize, and decomposition may occur without the added hydrogen peroxide solution reacting, so the ratio of hydrogen peroxide / titanium is more than 1. It is preferable to add. The reaction temperature may be either normal temperature or heating, but when a stable raw material such as an oxide is used, the higher the temperature, the faster the reaction can proceed. However, when the temperature is high, volatile basic substances such as ammonia easily escape, and the added hydrogen peroxide itself easily decomposes, causing turbidity, gelation, and precipitation before the raw material is completely solubilized. May be generated. If a large amount of basic substances are contained, titanium oxides such as anatase rarely crystallize even if the reaction temperature is raised, but it is preferable to react at 80 ° C or lower. In addition, the reaction can be promoted by stirring.

【0031】

The aqueous solution for forming a titanium oxide of the present invention can form an amorphous titanium oxide film by applying it on a substrate and then heating it at a temperature of less than 200 ° C. In addition, a dense crystalline titanium oxide film can be produced by heating to 200 ° C or higher. These films have excellent acid resistance and can be used as various corrosion-resistant coatings. Further, since the dispersion of anatase sol prepared from the aqueous solution for forming titanium oxide of the present invention can form a crystalline titania film only by coating, it is useful as a coating agent for a material that cannot be heat-treated. Further, the dispersion of anatase sol can be mixed with the stable titanium oxide forming solution of the present invention at an arbitrary ratio and used as a coating agent, thereby forming an anatase film having excellent adhesion. it can. Further, after applying the titanium oxide forming solution of the present invention on a substrate such as a synthetic resin using both a stable titanium oxide forming solution and an anatase sol dispersion, an anatase sol dispersion is applied thereto. Is applied to form a layer, the photocatalytic action of the titanium oxide layer on the surface causes decomposition of organic substances in the base material, and the coated titanium oxide layer can be prevented from peeling off from the base material.

【0032】

The solution for forming a titanium oxide of the present invention can be used for purposes such as forming a protective film and a photocatalyst layer, and a film having 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 have excellent dispersibility, and are mixed with various solid fine particles in advance, dispersed by an ultrasonic disperser, a ball mill, or the like, and then applied. It is also possible to prepare a composite in which other fine particles are supported or dispersed in the titanium oxide film obtained by drying and firing. Further, as the substrate to be coated, 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 powder can also be performed.

【0033】

[Example]

Hereinafter, the present invention will be described with reference to Examples and Comparative Examples. Example 1 Titanium dioxide was used as the titanium raw material. Weigh 0.8 g of titanium dioxide (titanium dioxide P25 manufactured by Nippon Aerodil Co., Ltd.), add 15 ml of a 2-fold diluted solution of 25 wt% ammonia water, add 40 ml of 30 wt% hydrogen peroxide solution to make 100 ml of distilled water. The mixture was stirred and allowed to stand at 25 ° C. for 2 days to dissolve and obtain a transparent yellow solution. The titanium concentration was 0.1 mol / l and the ammonium concentration was 1.1 mol / l.

【0034】

Then, H washed with distilled water.⁺ 30 g of a substituted cation exchange resin (Amberlite IR118 manufactured by Organo Corporation) was gradually added to the obtained solution and stirred to adjust the pH to 5. After separating the added cation exchange resin, 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.

【0035】

Furthermore, after setting the pH of the solution to 5 by the same operation as the removal of cations with the cation exchange resin, the decomposition of hydrogen peroxide and the removal of cations with the cation exchange resin were performed twice each to pH 5 An aqueous solution for forming a titanium oxide was obtained. The ammonium concentration in the obtained solution was 0.01 mol / l.

【0036】

In addition, the powder obtained by drying the obtained solution at 25 ° C was measured by an X-ray diffractometer (RAD-B manufactured by Rigaku Denki) using a copper target under the measurement conditions of an acceleration voltage of 30 kV and a current of 15 mA, and the results were obtained. Is shown in Fig. 1. The obtained liquid was amorphous. In addition, the powder was dried at 25 ° C and mixed with potassium bromide to form tablets, which was measured by the transmission method using a Fourier transform infrared absorption spectrum measuring device (FT / IR-5300 manufactured by JASCO Corporation). The results are shown in Fig. 2. 900cm^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group. In addition, at 25 ° C, there was no precipitation of precipitates even after being left for 30 days, and there was no change in the properties of the solution.

【0037】

Moreover, in all Examples and Comparative Examples, the titanium concentration and the ammonium concentration field were measured by the following measuring methods. (Measurement method of titanium concentration) Take an arbitrary amount of sample, dilute it 200 times with distilled water, and use an ICP emission spectroscopic analyzer (ICPS-2000 manufactured by Shimadzu Corporation) from a titanium standard solution (Wako Pure Chemical Industries, Ltd.). The titanium concentration was measured from the calibration curve prepared with the standard solutions having concentrations of 10 ppm, 20 ppm and 40 ppm prepared from the production concentration of 1000 ppm).

【0038】

(Measuring method of ammonium concentration) Take an arbitrary amount of the sample, and if it contains hydrogen peroxide, completely decompose it, dilute it 10 times, collect 1 ml of it in a container, and add 20 ml of distilled water. 1 ml of a zinc sulfate aqueous solution having a concentration of 0.35 mol / l was added, and an alkaline solution prepared 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, add 10 ml of 1.3 mol / l sodium phenolate solution and 1 ml of 0.15 mol / l disodium ethylenediamine tetraacetate and stir, add 5 ml of 1 volume% sodium hypochlorite aqueous solution, and add distilled water to make 50 ml. The mixture was stirred and filtered after 30 minutes. The absorbance of the obtained filtrate at 630 nm was measured with a spectrophotometer (UV-2100 manufactured by Shimadzu Corporation). In addition, ammonium chloride (special grade reagent) was dissolved and diluted to prepare a standard solution, which was measured by the same method as the test solution to prepare a calibration curve, and the concentration of the test solution was determined.

【0039】

Example 2 Metallic titanium was used as the titanium raw material. Weigh 0.48 g of metallic titanium powder (Metal titanium powder manufactured by Wako Pure Chemical Industries, Ltd.), add 7 ml of a 2-fold diluted solution of 25 wt% ammonia water, add 20 ml of 30 wt% hydrogen peroxide solution, and add 100 ml of distilled water. And this was left to stand at 25 ° C. for 24 hours to dissolve, and a yellow transparent solution was obtained. The titanium concentration was 0.1 mol / l and the ammonium concentration was 0.6 mol / l.

【0040】

Then, H washed with distilled water.⁺ 30 g of a substituted cation exchange resin (Amberlite IR118 manufactured by Organo) was gradually added to the obtained solution, stirred, and when the pH reached 5, the added cation exchange resin was separated and then irradiated with ultrasonic waves. The hydrogen peroxide was decomposed, and when the pH reached 8, 5 g of a cation exchange resin was added again to adjust the pH to 4.

【0041】

Further, the above operation of decomposing hydrogen peroxide and the operation of removing cations with a cation exchange resin were carried out twice 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.

【0042】

Moreover, when the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer, it was amorphous. Further, as in Example 1, when measured by a Fourier transform infrared absorption spectrum measuring device, it was 900 cm.^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group.

【0043】

Example 3 Titanium tetrachloride was used as the titanium raw material. A 10-fold diluted solution of 25 wt% ammonia water was added dropwise to a solution obtained by diluting 5 ml of a 60 wt% titanium tetrachloride aqueous solution to 500 ml with distilled water to adjust the pH to 7, and white gel-like titanium hydroxide was precipitated. , Filtering and washing was performed, and the total volume of the residue by filtration was adjusted to 150 ml with distilled water. Next, 25 ml of a 4-fold diluted solution of 25 wt% ammonia water and 20 ml of a 30 wt% hydrogen peroxide solution having a concentration and distilled water were added and left to stand, and after 12 hours, 250 ml of a yellow liquid containing titanium was obtained. The titanium-containing solution obtained had a titanium concentration of 0.1 mol / l, an ammonium concentration of 0.38 mol / l, and a chlorine concentration of 0.0086 mol / l.

【0044】

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

【0045】

Moreover, when the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer, it was amorphous. Further, as in Example 1, when measured by a Fourier transform infrared absorption spectrum measuring device, it was 900 cm.^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group.

【0046】

Example 4 Titanium tetrachloride was used as the titanium raw material. A 10-fold diluted solution of 25 wt% ammonia water was added dropwise to a solution obtained by diluting 5 ml of a 60 wt% titanium tetrachloride aqueous solution to 500 ml with distilled water to adjust the pH to 7, and white gel-like titanium hydroxide was precipitated. , Filter and wash, make the total volume of the residue with distilled water to 150 ml, cool this solution to 10 ° C or less with ice water, add 20 ml of 30 wt% aqueous hydrogen peroxide solution, and react for 12 hours to make it yellow translucent. A solution for forming titanium oxide was obtained.

【0047】

The obtained titanium oxide forming solution was treated with an anion exchange resin (Amberlite IRA410 manufactured by Organo) for 1 hour with 1N sodium hydroxide, washed, and OH.^- After adding 30 g of the replacement type and leaving it for 3 hours, after separating the anion exchange resin, add 25 ml of a 4-fold diluted solution of 25 wt% ammonia water and 10 ml of 30 wt% hydrogen peroxide solution and leave it. Then, after 12 hours, 250 ml of a yellow liquid containing titanium was obtained. The titanium concentration was 0.1 mol / l, the ammonium concentration was 0.39 mol / l, and the chlorine concentration was 0.0039 mol / l.

【0048】

Then, H washed with distilled water.⁺ 50 g of a substituted cation exchange resin (Amberlite IR118 manufactured by Organo) was added to the obtained solution and left to stand for 1 hour to remove residual ammonium ions, and then the added cation exchange resin was separated and removed. , The solution was cooled and kept at 7 ° C., and 10 ml of 30 wt% hydrogen peroxide was added to obtain a transparent yellow solution. The ammonium concentration in the solution was 0.013 mol / l.

【0049】

Moreover, when the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer, it was amorphous. Further, as in Example 1, when measured by a Fourier transform infrared absorption spectrum measuring device, it was 900 cm.^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group.

【0050】

Example 5 Titanium tetrachloride was used as the titanium raw material. To a solution obtained by diluting 5 ml of a 60 wt% titanium tetrachloride aqueous solution to 500 ml with distilled water, 20 ml of a 30 wt% hydrogen peroxide solution was added and stirred to prepare a brown transparent liquid, and the concentration was 25 wt% in this solution. A 10-fold diluted solution of aqueous ammonia was added dropwise to adjust the pH to 7, and a transparent yellow solution was prepared and left at 25 ° C. for 24 hours to precipitate a yellow precipitate. After filtering and washing this, the filtration residue was made up to 150 ml with distilled water.

【0051】

Next, the obtained titanium compound dispersion was treated with an anion exchange resin (Amberlite IRA410 manufactured by Organo) for 1 hour with 1N sodium hydroxide, washed, and OH.^- After adding 30 g of the substituted compound and leaving it for 30 minutes, the added anion exchange resin was separated using a synthetic resin net to remove chlorine ions, and then 180 ml was made with distilled water to make the concentration as the ammonia concentration. 25 ml of a 4-fold diluted solution of 25 wt% aqueous ammonia, 20 ml of a concentrated 30 wt% hydrogen peroxide solution and distilled water were added to obtain 250 ml of a transparent yellow liquid of a titanium compound after 12 hours. 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 mol / l.

【0052】

Then, H washed with distilled water in the obtained solution.⁺ Add 50 g of a substituted cation exchange resin (Organo Amberlite IR118) and leave it for 1 hour to remove ammonium ions, then separate and remove the added cation exchange resin, and cool the solution to 7 ° C. While holding the solution, 10 ml of a 30 wt% hydrogen peroxide solution was added to obtain a transparent yellow solution. The ammonium ion concentration in this solution was 0.011 mol / l.

【0053】

Moreover, when the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer, it was amorphous. Further, as in Example 1, when measured by a Fourier transform infrared absorption spectrum measuring device, it was 900 cm.^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group.

【0054】

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. When the powder obtained by drying this liquid was examined by X-ray diffraction in the same manner as in Example 1, it was confirmed that crystalline anatase was produced and that the obtained liquid was an anatase sol.

【0055】

Example 7 Metallic titanium was used as the titanium raw material. Weigh 0.48 g of metallic titanium powder (manufactured by Wako Pure Chemical Industries, Ltd.) into four containers, and add 5, 10, and 15 ml of 4-fold diluted solution of 25 wt% ammonia water to each of the three containers. Further, 40 ml of 30 wt% hydrogen peroxide solution and distilled water were added to all the containers to make 100 ml, and the mixture was stirred and then left at 25 ° C. for 20 hours.

【0056】

The titanium concentration was 0.1 mol / l, and the ammonium concentration was 0, 0.18, 0.37, and 0.55 mol / l, respectively. Samples with an ammonium concentration of 0.18 mol / l or less could not be completely dissolved, and a slight amount of insoluble matter remained. When it was 0.37 mol / l or more, it was completely transparently dissolved.

【0057】

H washed with distilled water in the obtained solution⁺ 30 g of a substituted cation exchange resin (Amberlite IR118 manufactured by Organo) was gradually added and stirred to adjust the pH to 5. Next, after separating the added cation exchange resin, ultrasonic waves were irradiated with an ultrasonic irradiation device to decompose hydrogen peroxide, and the pH increased with the decomposition of hydrogen peroxide. When the pH reached 8, 5 g of the cation exchange resin was added again and stirred to adjust the pH to 5, and then the cation exchange resin was separated. Then, decomposition of hydrogen peroxide by ultrasonic irradiation and treatment with a cation exchange resin were repeated twice to obtain a transparent yellow aqueous solution having a pH of 5. The ammonium concentration in the obtained liquid was 0.01 mol / l.

【0058】

Moreover, when the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer, it was amorphous. Further, as in Example 1, when measured by a Fourier transform infrared absorption spectrum measuring device, it was 900 cm.^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group.

【0059】

Example 8 Titanium dioxide was used as the titanium raw material. Weigh 0.8 g of titanium dioxide (titanium dioxide P25 manufactured by Nippon Aerodil Co., Ltd.) in 3 containers, add 5, 10 and 15 ml of 4-fold diluted solution of 25 wt% ammonia water, and add 30 wt% peroxidation. 40 ml of hydrogen water was added, and the mixture was stirred with distilled water to make 100 ml. Then, after heating at 60 ° C for 5 minutes, it was left to dissolve at 25 ° C for 30 hours. The titanium concentration was 0.1 mol / l, and the ammonium concentration was 0.18, 0.37, and 0.55 mol / l, respectively. Samples with an ammonium ion concentration of 0.37 mol / l or less could not be completely dissolved, and those without ammonia were hardly dissolved in titanium oxide powder, and only a white opaque suspension was obtained. It was.

【0060】

H washed with distilled water in the obtained solution⁺ 30 g of a substituted cation exchange resin (Amberlite IR118 manufactured by Organo) was gradually added and stirred to adjust the pH to 5, and then the cation exchange resin was separated. Next, a part of hydrogen peroxide was decomposed by irradiating ultrasonic waves with an ultrasonic irradiation device. When the pH increased with the decomposition of hydrogen peroxide and the pH reached 8, 5 g of the cation exchange resin was added again and stirred to adjust the pH to 5, and then the cation exchange resin was separated. Then, decomposition of hydrogen peroxide by ultrasonic irradiation and treatment with a cation exchange resin were repeated twice to obtain a transparent yellow aqueous solution having a pH of 5. The ammonium concentration in the obtained liquid was 0.01 mol / l.

【0061】

Example 9 20 ml each of the transparent solution obtained in the same manner as in Example 2 was dispensed, aqueous ammonia was added, and the ammonium ion concentrations in the solution were 0.0136, 0.021, 0.0284, 0.0358, 0.0423 mol / l and 0.055 mol /. The mixture was placed in a closed container and heated at 100 ° C for 6 hours.

【0062】

The powder obtained by drying this solution at 25 ° C. was measured by an X-ray diffractometer in the same manner as in Example 1, and the result is shown in FIG. Further, FIG. 4 shows a Fourier transform infrared absorption spectrum obtained by measuring the same powder in the same manner as in Example 1. Those with an ammonium concentration of 0.0284 mol / l or more are amorphous as a result of X-ray diffraction, and 900 cm as a result of examination by Fourier transform infrared spectroscopy.^-1Absorption was observed in the vicinity, and it was confirmed that a peroxo group was present.

【0063】

On the other hand, those with 0.021 mol / l or less contained anatase crystals as a result of X-ray diffraction and were found to be in a sol state. That is, anatase sol was obtained only when the ammonium concentration was lower than the titanium concentration. In addition, when ammonia was only added without heat treatment at 100 ° C, those with 0.0423 mol / l or less were transparent at room temperature for 1 month or more and did not change, but those with 0.055 mol / l became turbid. It was unstable. In addition, a stable peroxotitanic acid aqueous 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 a concentration higher than that.

【0064】

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

【0065】

Moreover, when the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer, it was amorphous. Further, as in Example 1, when measured by a Fourier transform infrared absorption spectrum measuring device, it was 900 cm.^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group.

【0066】

Example 11 Metallic titanium was used as the titanium raw material. Collect 0.48 g of metallic titanium powder (metal titanium powder manufactured by Wako Pure Chemical Industries, Ltd.), add 7 ml of a 2-fold diluted solution of 25 wt% ammonia water, add 20 ml of 30 wt% hydrogen peroxide solution, and 100 ml with distilled water. And this was left to stand at 25 ° C. for 24 hours to dissolve, and a yellow transparent solution was obtained. The titanium concentration was 0.1 mol / l and the ammonium ion concentration was 0.6 mol / l.

【0067】

Then H⁺ 30 g of a substituted cation exchange resin (Amberlite IR118 manufactured by Organo) was gradually added to the obtained solution, stirred, and when the pH reached 5, the added cation exchange resin was separated and then ultrasonically irradiated. The hydrogen peroxide was decomposed to obtain Solution 1. Then, 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, and then ultrasonic irradiation was performed to decompose hydrogen peroxide to obtain the 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 then ultrasonic irradiation was performed to decompose hydrogen peroxide to obtain the solution 3.

【0068】

Each solution was yellow and transparent, and the ammonium ion concentration was 1: 0.058 mol / l for solution, 0.043 mol / l for solution, and 0.020 mol / l for solution. Solution 2 and Solution 3 did not change for more than 1 month, but Solution 1 became turbid and solids precipitated from the second day after being left at 25 ° C.

【0069】

Moreover, when the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer, it was amorphous. Further, as in Example 1, when measured by a Fourier transform infrared absorption spectrum measuring device, it was 900 cm.^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group.

【0070】

Example 12 Metallic titanium was used as the titanium raw material. Weigh 0.48 g of metallic titanium powder (Metal titanium powder manufactured by Wako Pure Chemical Industries, Ltd.), put 4 g of sodium hydroxide (special grade reagent manufactured by Wako Pure Chemical Industries, Ltd.) into a solution dissolved in 50 g of distilled water, and peroxidize at a concentration of 30% by weight. 20 ml of hydrogen water was added, and the mixture was stirred with distilled water to make 100 ml, and this was left at 25 ° C. for 15 hours to dissolve and obtain a transparent yellow solution. The titanium concentration was 0.1 mol / l and the sodium concentration was 1 mol / l.

【0071】

Then H⁺ 60 g of a substituted cation exchange resin (Amberlite IR118 manufactured by Organo) was gradually added to the obtained solution, stirred, and when the pH reached 5, the ion exchange resin was separated and then ultrasonically irradiated to hydrogen peroxide. When the pH reached pH 8, 4 g of the cation exchange resin was added again to separate the added cation exchange resin when the pH reached 5, and then ultrasonic irradiation was performed to decompose hydrogen peroxide to pH 8. At that point, the cation exchange resin was added again, ultrasonic treatment was performed, and 4 g was added to bring the pH to 5. After the resin was separated, sonication and treatment with a cation exchange resin were repeated 3 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.

【0072】

Moreover, when the powder obtained by drying the obtained solution in the same manner as in Example 1 was measured by an X-ray diffractometer, it was amorphous. Further, as in Example 1, when measured by a Fourier transform infrared absorption spectrum measuring device, it was 900 cm.^-1Absorption was observed in the vicinity, confirming the presence of a peroxo group.

【0073】

Example 13 and Comparative Example 1 Metallic titanium was used as the titanium raw material. Collect 0.48 g of metallic titanium powder (metal titanium powder manufactured by Wako Pure Chemical Industries, Ltd.), add 7 ml of a 2-fold diluted solution of 25 wt% ammonia water, add 20 ml of 30 wt% hydrogen peroxide solution, and 100 ml with distilled water. And this was left to stand at 25 ° C. for 24 hours to dissolve, and a yellow transparent solution was obtained. The titanium concentration was 0.1 mol / l and the ammonium concentration was 0.6 mol / l.

【0074】

Then H⁺ After stirring by changing the input amount of the substituted cation exchange resin (Organo Amberlite IR118), the pH, titanium concentration, and ammonium ion concentration of the solution from which the added cation exchange resin was removed 10 minutes later were measured. The results are shown in Table 1. Hydrogen peroxide remained in all the samples and foaming continued, and after 3 days, the foaming subsided and the pH increased, and turbidity and precipitation occurred in all the 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 4 7 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 2.5 4 0.014 0.017 Sample 7 65 2.5 4 0.004 0.011 [0076]

Comparative example 2 In Example 1, the titanium oxide-forming solution prepared without performing the treatment operation with the 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】

[Effect of the invention]

Metallic titanium, or a compound containing only one of metallic titanium and hydrogen or oxygen as a raw material, and cations derived from the basic substance in a solution for forming a titanium oxide dissolved by a basic substance and a hydrogen peroxide solution. By removing hydrogen peroxide stepwise, the solution for forming titanium oxide can be stabilized, and a coating agent for forming titanium oxide having excellent characteristics can be produced.

[Simple explanation of drawings]

[Figure 1]

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

[Figure 2]

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

[Fig. 3]

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

[Fig. 4]

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