JPH05263045A - Film-forming coating liquid and its production - Google Patents

Abstract

PURPOSE:To provide the subject liq. which contains a reactional product of a silica sol prepd. by the hydrolysis and polycondensation of a specific alkoxysilane with the alkoxysilane or its partial hydrolyzate and forms a voidless and pinholeless dense film by specifying the ion concn. of the liq. CONSTITUTION:This coating liq. contains a reactional product of a silica sol prepd. by the hydrolysis and polycondensation of an alkoxysilane of the formula: RnSi(OR')4-n (wherein R and R' are each 1-8C alkyl, aryl, or vinyl; and (n) is 0-3) with the alkoxysilane or its partial hydrolyzate, and has an ion concn. of 1.0mmol/l or lower.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating solution for forming a coating film and a method for producing the same, and more specifically, a coating solution for forming a coating film and a method for producing the same for obtaining a dense coating film with few voids and pinholes. Regarding

[0002]

TECHNICAL BACKGROUND OF THE INVENTION In semiconductor insulating films, etc.,
It is required to have excellent adhesion to the base material, mechanical strength, chemical resistance, moisture resistance, insulation, etc. For this purpose, the smaller the number of voids and pinholes in the coating, the less Formation of a silica-based coating film having such excellent properties is desired when manufacturing a semiconductor device or the like.

Such a silica-based coating is formed by a coating solution as described in, for example, Japanese Patent Application Laid-Open No. 3-263476, that is, a general formula R _n Si (OR ') _4-n (wherein
R and R'represent an alkyl group having 1 to 8 carbon atoms, an aryl group or a vinyl group, and n is an integer of 0 to 3. ) Is formed by using a coating solution for forming a film, which contains a reaction product of a silica sol (A) obtained by hydrolytic polycondensation of an alkoxysilane represented by (4) and the alkoxysilane or a partial hydrolyzate (B) thereof. be able to.

The inventors of the present invention have made earnest studies to obtain a dense silica-based coating film having fewer voids and pinholes. As a result, when an alkoxysilane represented by the above formula is hydrolyzed and polycondensed, a silica sol is obtained. When an alkali used as a catalyst or an acid or an alkali used as a catalyst when partially hydrolyzing the alkoxysilane remains as ions in the coating liquid, the ions are formed from the coating liquid. It has been found that the coating has voids, pinholes, etc., or the coating characteristics such as insulation are deteriorated.

As a result of further studies, the present inventors have found that
It was found that when the concentration of ions contained in the coating liquid is lowered to 1.0 mmol / liter or less, a dense silica-based coating film with few voids and pinholes can be obtained, and the present invention is completed. I arrived.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. It is dense and has little voids, pinholes, etc., and has a high degree of adhesion, mechanical strength and chemical resistance. A coating solution for forming a film, which has excellent properties, moisture resistance, insulation properties, and can form a silica-based coating having a low relative dielectric constant, and a coating solution for forming a film having such excellent properties. It is an object of the present invention to provide a method for producing a coating liquid for forming a coating film which can be used.

[0007]

SUMMARY OF THE INVENTION A coating solution for forming a coating film according to the present invention has a general formula R _n Si (OR ') _4-n (wherein R and R'have 1 carbon atoms).
~ 8 represents an alkyl group, an aryl group or a vinyl group, and n is an integer of 0-3. ) A silica sol (A) obtained by hydrolytic polycondensation of an alkoxysilane represented by
And a reaction product of the above-mentioned alkoxysilane or a partial hydrolyzate thereof (B) with each other, wherein the ion concentration in the coating liquid is 1.0 mmol / liter or less. There is.

The coating liquid for forming a coating film contains the silica sol (A), the alkoxysilane or a partial hydrolyzate thereof (B) used as a raw material for the coating liquid for forming a coating film in the process of producing the coating liquid for forming a coating film. The cation exchange resin treatment and the anion exchange resin treatment are performed on either the liquid containing solution or the coating solution for forming a film to reduce the ion concentration in the coating solution for forming a film to 1.0 mmol / liter or less. It can be manufactured.

[0009]

DETAILED DESCRIPTION OF THE INVENTION The coating solution for forming a coating film and the method for producing the same according to the present invention will be specifically described below.

Coating Solution for Forming a Film The coating solution for forming a film according to the present invention has the general formula R _n Si
(OR ') _4-n (In the formula, R and R'represent an alkyl group having 1 to 8 carbon atoms, an aryl group or a vinyl group, and n is 0 to
It is an integer of 3. ), A reaction product of the silica sol (A) obtained by hydrolytic polycondensation of an alkoxysilane and the alkoxysilane or a partial hydrolyzate thereof (B).

In the coating liquid for forming a coating film according to the present invention, the ion concentration in the coating liquid is 1.0 mmol / liter or less, preferably 0.6 mmol / liter or less. This ion concentration means the total ion concentration of the cations and anions in the coating liquid, and in the present invention, the cation concentration and the anion concentration are measured as follows.

10 ml of the coating liquid for forming a film was mixed with 90 ml of purified pure water, stirred at room temperature for 1 hour, filtered, and 100 ml of purified pure water was passed through the filter medium after filtration to collect the filtrate. ..

The metal ion concentration contained in this recovered filtrate is measured by the atomic absorption method, and the ammonium ion concentration and the anion concentration are measured by the ion chromatography method. In the present invention, the ion concentration in the coating solution for forming a coating is extremely low, 1.0 mmol / liter or less, so that there are few voids and pinholes as compared with the conventional coating, and it is dense and adheres well. It is possible to form a silica-based coating having excellent properties, mechanical strength, chemical resistance, moisture resistance, insulation, etc., and having a low relative dielectric constant.

That is, the coating solution for forming a film containing the reaction product of the silica sol (A) and the alkoxysilane or its partial hydrolyzate (B) is the acid or alkali used as a catalyst during the hydrolysis of the alkoxysilane. And are present as ions in the coating liquid for forming a film.

These acids or alkalis act as a polycondensation catalyst when the polycondensation of the alkoxysilane contained in the coating liquid proceeds further to form a film.
As a result, the polycondensation rate of the alkoxysilane contained in the coating solution becomes faster during film formation, and the film is formed with the acid or alkali in the coating solution or part of the organic solvent incorporated. May progress. Some of these acids or alkalis or organic solvents are gasified and removed when the coating formed on the substrate is heated and cured, but the traces may become voids or pinholes,
For this reason, the denseness of the coating is lowered.

Even after the coating is heated and cured, if some of the above acids or alkalis or metal ions remain in the coating, they act as impurities, and, for example, insulative properties. The properties of the coating may deteriorate.

In the present invention, ions contained in the coating solution such as acid ions or alkali ions remaining in the coating solution as described above, and trace amounts of metal ions used as a catalyst or remaining as impurities. By removing the, the cause of generation of voids, pinholes, etc. at the time of forming the film is removed, and at the same time the insulating property is improved and a film having a low relative dielectric constant can be obtained.

Method for producing coating liquid for forming film The coating liquid for forming a coating film according to the present invention as described above is a silica sol (A) used as a raw material for the coating liquid for forming a film in the process of producing the coating liquid for forming a film. , And a liquid containing alkoxysilane or a partial hydrolyzate thereof (B), and a coating liquid for forming a film obtained from these raw materials are treated with a cation exchange resin and an anion exchange resin. Then, it can be produced by setting the ion concentration in the coating liquid for forming a film to 1.0 mmol / liter or less.

When the treatment with the cation exchange resin and the treatment with the anion exchange resin are performed, the cation exchange resin and the anion exchange resin may be alternately treated, or the cation exchange resin and the cation exchange resin may be used. It may be treated with a mixed resin with an anion exchange resin.

The silica sol (A) used as a raw material for the coating liquid for forming a film can be obtained by the following method. That is, the silica sol (A) is obtained by subjecting an alkoxysilane represented by the following general formula to hydrolysis polycondensation in the presence of water, an organic solvent and an alkali catalyst. A known method can be adopted.

R _n Si (OR ') _{4-n In the} formula, n represents an integer of 0 to 3, and R and R'have 1 carbon atoms.
Represents an alkyl group, an aryl group or a vinyl group of 8;

Specific examples of such alkoxysilanes include tetramethoxysilane, tetraethoxysilane,
Tetraisopropoxysilane, tetrabutoxysilane,
Tetraoctylsilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane,
Examples thereof include methyltriisopropoxysilane, methyltributoxysilane, octyltriethoxysilane, phenyltrimethoxysilane, vinyltrimethoxysilane, dimethyldimethoxysilane, diethyldiethoxysilane, trimethylmonomethoxysilane, and triethylmonoethoxysilane.

In the present invention, these alkoxysilanes may be used alone or in combination of two or more. Examples of the organic solvent include alcohols, ketones, ethers, esters and the like. More specifically, for example, alcohols such as methanol, ethanol, propanol, butanol, etc., ethylene glycol ethers such as methyl cellosolve, ethyl cellosolve, etc. Examples thereof include glycols such as ethylene glycol and propylene glycol, and ethers such as methyl acetate, ethyl acetate and methyl lactate.

As the alkali catalyst, compounds showing alkalinity in an aqueous solution such as ammonia, amine, alkali metal catalyst, quaternary ammonium compound and amine coupling agent are used, and the pH of the reaction mixture is preferably 7 to 12. Is used in an amount such that it is 8-11.

The method for preparing the silica sol (A) will be described in more detail. For example, while stirring a water-alcohol mixed solvent, an alkoxysilane and an alkali catalyst such as aqueous ammonia are added to the mixed solvent. React with alkoxysilane.

At this time, water is 5 to 50 mol, preferably 5 to 1 mol per 1 mol of Si-OR groups contained in the alkoxysilane.
The amount of the alkali catalyst used is such that the above-mentioned pH is reached, for example, 0.01-1.0.
It is blended in an amount such that it is mol / SiO ₂ mol, preferably 0.05 to 0.8 mol / SiO ₂ mol.

The hydrolysis polycondensation reaction of the alkoxysilane is usually carried out at a temperature not higher than the boiling point of the solvent used under normal pressure, preferably at a temperature 5 to 10 ° C. lower than this boiling point. It can also be carried out under pressure in a pressure vessel, and in this case, it is carried out at a temperature higher than the boiling point of the solvent under normal pressure.

When the alkoxysilane is hydrolyzed under such conditions, polycondensation of the alkoxysilane proceeds three-dimensionally, silica particles are produced, and the produced silica particles grow.

In this way, silica particles are produced.
After the growth, the heat treatment may be performed at a temperature equal to or higher than the boiling point of the solvent used for a certain period of time. By performing such heat treatment, polycondensation of alkoxysilane is further promoted, and a silica sol in which silica particles having a high density are dispersed can be obtained.

A silica sol is thus obtained,
The silica sol (A) used in the present invention has an average particle size of about 50 to 500 angstroms, particularly 100 to 5 angstroms.
A silica sol in which uniform silica particles of 00 angstrom are dispersed in a solvent is preferable. When the particle size is less than 50 angstroms, when a film is formed using a coating solution for forming a film obtained by using silica sol containing such silica particles as a raw material, cracks may occur on the formed film surface, Further, when the average particle diameter of silica particles contained in the silica sol exceeds 500 angstroms, voids in the coating often occur and a dense coating may not be obtained.

In the present invention, it is desirable that the silica particles are contained in the silica sol in an amount of about 50% by weight or less, preferably 40% by weight or less in terms of SiO ₂ . If the content of silica particles contained in this silica sol exceeds 50% by weight, gelation tends to occur.

In the present invention, the unpurified silica sol obtained by the above method can be used as it is, but the reaction between the silica sol (A) and the alkoxysilane or its partial hydrolyzate (B) as described below is carried out. Before carrying out, it is preferable to replace the solvent from the mixed solvent of water and the organic solvent with water in advance by means such as ultrafiltration from silica sol.

Such solvent replacement operation may be carried out before the above-mentioned heat treatment of the silica sol. In the present invention, the silica sol obtained as described above may be subjected to a deionization treatment with a cation exchange resin and an anion exchange resin.

A reaction product obtained by reacting the silica sol (A) thus obtained with an alkoxysilane or a partial hydrolyzate (B) thereof is used in the coating solution for forming a film of the present invention. ..

Used in the reaction with the above silica sol (A)
Alkoxysilane as a raw material for silica sol (A)
Similar to the used alkoxysilane, the general formula R_nSi (O
R ') _4-n(In the formula, R and R'are alkyl having 1 to 8 carbons.
Represents a group, an aryl group or a vinyl group, and n is 0 to 3
It is an integer. ) Alkoxysilane
Selected as a raw material for silica sol (A)
It does not have to be the same as the alkoxysilane used.

In the reaction process of the reaction between the silica sol (A) and the alkoxysilane or its partial hydrolyzate (B), the growth of silica particles or the formation of new silica particles does not occur in the silica sol, and On the surface of the silica particles contained therein, a binding reaction between the silica particles and a new alkoxysilane or a partial hydrolyzate (B) thereof occurs, and as a result, a coating solution meeting the object of the present invention can be obtained.

As described above, a reaction product of silica sol (A) and an alkoxysilane can be used in the coating solution for forming a coating film of the present invention, but a reaction product of silica sol (A) and a partial hydrolyzate of alkoxysilane is used. It is preferable to use a reactant. When the silica sol (A) and the partial hydrolyzate of the alkoxysilane are mixed and reacted as described above, gelation due to aggregation of the sol tends not to occur.

When the partial hydrolysis of the alkoxysilane is carried out, water, an organic solvent, an acid or an alkali catalyst is usually used. Examples of the organic solvent and the alkali catalyst include those mentioned above. As the acid catalyst, specifically, inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid, organic acids such as acetic acid and oxalic acid, or compounds showing acidity in an aqueous solution such as metal soap are used.

The amount of water used for partial hydrolysis of the alkoxysilane is usually the Si contained in the alkoxysilane.
0.1 to 2 mol, preferably 0.5 per mol of the OR group.
~ 2 moles. When an acid catalyst is used in the partial hydrolysis of alkoxysilane, the pH of the reaction solution is usually 0 to 6, preferably 1 to 3, and when an alkali catalyst is used. The reaction solution is used in such an amount that the pH of the reaction solution is usually 7 to 10, preferably 7 to 8.

The molecular weight of the partially hydrolyzed alkoxysilane obtained under the above conditions is about 100 to 10,000, preferably 500 to 5, in terms of polystyrene equivalent molecular weight.
000 is desirable.

In the present invention, the partial hydrolyzate of the alkoxysilane is obtained by such a method, but it can also be obtained by the following method. 1) General formula R ¹ _n Si (OR ² ) _4-n (In the formula, R ¹ represents an alkyl group having 1 to 8 carbon atoms, an aryl group or a vinyl group, and R ² represents an alkyl group having 1 to 4 carbon atoms. , An aryl group or a vinyl group, and n is an integer of 0 to 3.)
One or more of alkoxysilanes represented by
A method in which partial hydrolysis is carried out in the presence of an organic solvent, water and an alkali catalyst, and then the resulting partially hydrolyzed product is further partially hydrolyzed in the presence of water and an acid catalyst.
54279).

2) General formula R ¹ _n Si (OR ² ) _4-n (In the formula, R ¹ represents an alkyl group having 1 to 8 carbon atoms, an aryl group or a vinyl group, and R ² has 1 to 4 carbon atoms. Which represents an alkyl group, an aryl group or a vinyl group, and n is an integer of 0 to 3) is partially hydrolyzed in the presence of an organic solvent, water and an acid catalyst. A method of decomposing, then contacting the obtained partial hydrolyzate with an alkali, and adding an acid to the solution thus obtained to make it acidic (JP-A-3-115379).

Examples of the organic solvent, acid catalyst and alkali catalyst used in the above method include those mentioned above. In the present invention, the liquid containing the partially hydrolyzed product of the alkoxysilane obtained as described above may be subjected to deionization treatment with a cation exchange resin and an anion exchange resin.

When the coating solution for forming a coating film according to the present invention is produced, the silica sol (A) as described above and the alkoxysilane or its partial hydrolyzate (B) are contained in the silica sol (A). in terms of SiO ₂ by weight of the silica particles that are (W _a) / alkoxysilane or a partial hydrolyzate thereof calculated as SiO ₂ calculated weight of _(B) (W B) is 0.1 to 1
It is preferable to mix them in a weight ratio of 0.0, preferably 0.25 to 4.0.

When the weight ratio (W _A / W _B ) exceeds 10.0, a coating for forming a film containing a reaction product of such a silica sol (A) and an alkoxysilane or a partial hydrolyzate (B) thereof. The coating film formed from the liquid has excellent heat resistance and moisture resistance, but when the film thickness increases, cracks tend to easily occur, while on the other hand, when the weight ratio (W _A / W _B ) is less than 0.1, The heat resistance and moisture resistance of the film tend to be poor.

The coating solution for forming a coating used for forming the silica-based coating is about 100 ° C. or lower after mixing the silica sol (A) and the alkoxysilane or its partial hydrolyzate (B) as described above. It is preferably obtained by performing heat treatment at a temperature of preferably 80 ° C. or lower for usually 0.5 to 5 hours, preferably 1 to 3 hours. The lower limit of this heat treatment is not particularly limited, but the lower the temperature, the longer the reaction time and the lower the productivity. On the other hand, 1
If the temperature exceeds 00 ° C, the hydrolysis reaction of the alkoxysilane proceeds too much, which is not preferable.

Next, the coating solution for forming a film thus obtained is subjected to a deionization treatment with a cation exchange resin and an anion exchange resin, and the ion concentration in the coating solution is adjusted to a specified value or less. As described above, the silica sol (A) and the alkoxysilane partial hydrolyzate (B) are used.
If the cation-exchange resin and anion-exchange resin have been previously deionized with a solution containing, and the ion concentration of the coating liquid for film formation obtained using these is below the specified value, the film is formed again. It is not necessary to subject the coating solution for deionization as described above.

In the present invention, the coating liquid for forming a coating film having an ion concentration of 1.0 mmol / liter or less is thus obtained. When a coating film is formed on a substrate using the coating liquid for forming a coating film of the present invention, a spray method, a spin coating method, a dipping method, a roll coating method is applied to the surface of the substrate such as glass, plastic, or ceramic. The silica-based coating was formed by applying the coating liquid for film formation obtained as described above by various methods such as a screen printing method and a transfer printing method, and then drying and baking the obtained coating film. A substrate is obtained.

The above firing temperature is usually 150 ° C. to 80 ° C.
The temperature is 0 ° C, preferably about 200 ° C to 800 ° C. Further, after the coating step, the drying step, or during the drying step, the uncured film is irradiated with an electromagnetic wave having a wavelength shorter than visible light, such as ultraviolet rays, electron beams, or X-rays, or The coating can be cured by heating in a gas atmosphere that promotes curing, for example, a gas atmosphere of ammonia, ozone, or the like.

The film thickness of the film thus formed is
It is usually 0.05 to 2 μm, preferably 0.1 to 1 μm. The coating film obtained from the coating liquid for forming a coating film according to the present invention as described above has almost no defects such as voids and pinholes, excellent adhesion, excellent chemical resistance, excellent moisture resistance, etc. It has a very low dielectric constant and does not generate cracks. Therefore, the coating liquid for forming a coating film according to the present invention is suitable for forming various protective films, insulating films for semiconductors, and the like.

In a device such as a liquid crystal display device in which an electrode film such as an ITO film is formed on a glass substrate, the coating liquid for forming a film according to the present invention is used between the glass substrate and the electrode film. Forming the coating by using the above method can prevent an alkali attack, that is, an alkali component such as Na contained in the glass substrate from entering the electrode film, and is therefore suitable as a so-called alkali passivation film.

[0052]

EFFECT OF THE INVENTION According to the coating solution for forming a coating film of the present invention, there are almost no voids, pinholes, etc., and it is dense and has excellent adhesion, mechanical strength, chemical resistance, moisture resistance, insulation, etc. A silica-based coating film which is excellent and has a low relative dielectric constant can be formed on a substrate.

Further, according to the method for producing a coating liquid for forming a coating film of the present invention, a coating liquid for forming a coating film capable of forming a coating film having such excellent properties can be easily and reliably produced.

[0054]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0055]

Example 1 —Preparation of silica sol— 110.4 g of ethyl silicate-28 (SiO ₂ concentration; 28% by weight, manufactured by Tama Chemical Industry Co., Ltd.) was added to a mixed solution of 101.5 g of pure water and 406.1 g of methanol. After the addition, 89.5 g of 5% aqueous ammonia was added over 3 hours while the liquid was heated to maintain the temperature of the liquid at 65 ° C., whereby silica particles were generated in the liquid. The liquid after the addition was maintained at the same temperature for 1 hour to age the silica particles in the liquid. Then, from the liquid containing the silica particles, unreacted ethyl silicate, methanol and ammonia contained in the liquid were removed by ultrafiltration, and pure water was added at the same time, and the SiO ₂ concentration was 5% by weight.
A silica sol A in which silica particles having an average particle diameter of 100 Å were dispersed was obtained.

-Preparation of Partial Hydrolyzate of Alkoxysilane- Concentrated nitric acid was added to a mixed solution of 357.1 g of ethyl silicate-28, 402.9 g of ethanol and 240.0 g of pure water to adjust the pH of the mixed solution to 1 Adjusted to .5.
The alkoxysilane partial hydrolyzate a was obtained by heating this mixed solution at 50 ° C. for 1 hour.

-Preparation of coating liquid-Silica sol A obtained as described above and alkoxysilane partial hydrolyzate a were mixed at a solid content weight ratio of 7/3 and then at 50 ° C for 1 hour. By heating, the silica sol and the partial hydrolysis product of the alkoxysilane were reacted. . Then, a liquid containing this reaction product is mixed with an equal amount of a cation exchange resin and an anion exchange resin (AG501,
Deionization treatment was performed by passing through a column packed with Bio-Red Co., Ltd.).

Then, the water and alcohol contained in this solution were distilled off by a rotary evaporator, and then replaced with propylene glycol monopropyl ether to obtain Si.
A coating solution having an O ₂ concentration of 20% by weight was obtained.

-Evaluation of coating- The ion concentration of the coating liquid thus obtained is measured, and this coating liquid is applied to a glass substrate by a spinner method, dried, and then baked at 350 ° C for 30 minutes. To form a coating film having a thickness of about 2.0 μm, and the following evaluation was performed.

(1) Presence or absence of cracks; judged by visual observation. (2) Denseness; 50% HF and 60% HNO ₃
Immersed in a mixed acid with (HF / HNO ₃ = 5/100 weight ratio) for 1 minute and measure the change in film thickness.

(3) Alkali resistance: Immersed in a 5 wt% NaOH aqueous solution at 40 ° C. for 20 minutes, and measured the change in film thickness. (4) Insulation: Measured with an insulation resistance meter.

(5) Alkali passivation property: After the NESA film is formed by the CVD method on the surface of the silica-based coating of the glass substrate with the silica-based coating obtained as described above,
This silica-coated glass substrate was heat-treated at 450 ° C., and evaluated by the difference in surface resistance of the silica-based coating before and after heating.

(6) Relative permittivity; The coating liquid is applied to the surface of a silicon wafer by a spinner method and dried, and then 3
It is baked in a nitrogen stream for 0 minutes to form a film having a thickness of about 1 μm, and an aluminum film is formed on the surface of this film by a sputtering method, and the relative dielectric constant is measured.

Table 1 shows the ion concentration of the coating liquid and the above evaluation results. The ion concentration of the coating solution was measured by the method shown on page 3 above.

[0065]

Example 2 —Preparation of silica sol— 126.4 g of methyl silicate-51 (SiO ₂ concentration; 51% by weight, manufactured by Tama Chemical Industry Co., Ltd.) was added to a mixed solution of 203.0 g of pure water and 812.2 g of methanol. After the addition, 150 g of 5% aqueous ammonia was added over 5 hours while heating the liquid to keep the temperature of the liquid at 45 ° C.
This produced silica particles in the liquid. The liquid after the addition was maintained at the same temperature for 1 hour to age the silica particles in the liquid. Then, the unreacted ethyl silicate, methanol and ammonia contained in the liquid are removed from the liquid containing the silica particles by ultrafiltration, and pure water is added at the same time, and the SiO ₂ concentration is 5% by weight. To obtain a silica sol B in which silica particles having a particle size of 110 Å were dispersed.

-Preparation of partial hydrolysis product of alkoxysilane- 196.1 g of methyl silicate-51, ethanol 6
1% ammonia water was added to a mixed solution of 83.9 g and pure water 120.0 g to adjust the pH of the mixed solution to 8.0. This mixed solution was heated at 50 ° C. for 1 hour to hydrolyze methyl silicate, and then the pH was adjusted to 2. with concentrated nitric acid.
It was adjusted to 5 and further heated at 50 ° C. for 30 minutes to obtain an alkoxysilane partial hydrolyzate b.

-Preparation of coating liquid-Same as in Example 1 except that the silica sol B thus obtained and the alkoxysilane partial hydrolyzate b were mixed in a solid content weight ratio of 1/1. Then, the reaction between the silica sol and the partial hydrolyzate of alkoxysilane, the deionization treatment of the solution containing the obtained reaction product and the solvent substitution were sequentially carried out to obtain a coating solution having a SiO ₂ concentration of 20% by weight.

-Evaluation of Coating- The coating solution obtained as described above was measured for ionic concentration in the same manner as in Example 1, and the coating was evaluated in the same manner as in Example 1.

The results are shown in Table 1.

[0070]

Example 3 —Preparation of Silica Sol— Silica sol A obtained in Example 1 was subjected to deionization treatment in the same manner as in the coating liquid of Example 1 to obtain silica sol C.

-Preparation of Partial Hydrolyzate of Alkoxysilane-Partial Hydrolyzate of Alkoxysilane Obtained in Example 2
The solution containing the same was subjected to deionization treatment in the same manner as the coating solution of Example 1 to obtain an alkoxysilane partial hydrolyzate c.

-Preparation of coating liquid- The silica sol C thus obtained and the alkoxysilane partial hydrolyzate c were mixed at a solid content weight ratio of 3/7, and the same conditions as in Example 1 were applied. It was made to react with. Then, the liquid containing this reaction product was subjected to the same deionization treatment as in Example 1, the water and alcohol contained in this liquid were distilled off by a rotary evaporator, and then replaced with ethyl lactate to obtain SiO 2. ₂ A coating solution having a concentration of 20% by weight was obtained.

-Evaluation of coating- The ion concentration of the coating liquid obtained as described above was measured in the same manner as in Example 1, and the coating was evaluated in the same manner as in Example 1.

The results are shown in Table 1.

[0075]

[Example 4] -Preparation of silica sol-While maintaining a mixed solution of 139.1 g of pure water and 169.9 g of methanol at 60 ° C while heating, a mixed solution of ethyl silicate-28 in water / methanol (ethyl) was added to the mixed solution. Silicate; 532.5 g, water / methanol mixed solvent; 2450 g, water / methanol weight ratio; 1/4) 2
982.5 g and 596.4 g of 0.25% aqueous ammonia were simultaneously added over 52 hours, thereby forming silica particles in the mixed solution. The liquid after the addition was maintained at the same temperature for 3 hours to age the silica particles in the liquid. Then, unreacted ethyl silicate, methanol and ammonia contained in the liquid are removed from the liquid containing the silica particles by ultrafiltration, and at the same time pure water is added,
A silica sol D having a SiO ₂ concentration of 10% by weight and having silica particles having an average particle diameter of 250 Å dispersed therein was obtained.

-Preparation of partial hydrolyzate of alkoxysilane-454.5 g of methyltrimethoxysilane, ethanol 1
Concentrated nitric acid was added to a mixed solution of 85.5 g and pure water 360.0 g to adjust the pH of the mixed solution to 1.0. This mixed solution is heated at 50 ° C. for 2 hours to partially hydrolyze the alkoxysilane.
Aqueous ammonia was added to adjust the pH to 7.0, and this solution was heated at 50 ° C. for 2 hours to obtain an alkoxysilane partial hydrolyzate d.

-Preparation of coating liquid- Silica sol D obtained as described above and alkoxysilane partial hydrolyzate d were mixed at a solid content weight ratio of 7/3, and the same as in Example 3. Reaction of silica sol with partial hydrolysis product of alkoxysilane, deionization treatment of the liquid containing the obtained reaction product, and solvent replacement are sequentially carried out, and Si
A coating solution having an O ₂ concentration of 20% by weight was obtained.

-Evaluation of coating film- The ion concentration of the coating liquid obtained as described above was measured in the same manner as in Example 1, and the coating film was evaluated in the same manner as in Example 1.

The results are shown in Table 1.

[0080]

Example 5-Preparation of silica sol-In place of ethyl silicate-28, 169.4 g of methyltrimethoxysilane and 266.3 g of ethyl silicate-28 were used.
A silica sol was prepared in the same manner as in Example 4 except that the SiO ₂ concentration was 10 wt% and the average particle size was 25.
Silica sol E having 0 angstrom silica particles dispersed therein was obtained.

-Preparation of partial hydrolyzate of alkoxysilane- 17.3% ammonia water was added to a mixed solution of 227.3 g of methyltrimethoxysilane, 357.1 g of ethyl silicate-28, 175.0 g of ethanol and 240.0 g of pure water. The pH of the mixed solution was adjusted to 8.5. The mixed solution is heated at 50 ° C. for 2 hours to partially hydrolyze the alkoxysilane, and then a 95% aqueous acetic acid solution is added to adjust the pH to 4 and then the solution is adjusted to 5
By heating at 0 ° C. for 5 hours, an alkoxysilane partial hydrolyzate e was obtained.

-Preparation of coating liquid-Same as in Example 3 except that the silica sol E thus obtained and the alkoxysilane partial hydrolyzate e were mixed at a solid content weight ratio of 4/1. The silica sol was partially reacted with the alkoxysilane partially hydrolyzed product, and the solution containing the obtained reaction product was sequentially subjected to deionization treatment and solvent substitution to obtain a coating liquid having a SiO ₂ concentration of 20% by weight.

-Evaluation of coating film- The ion concentration of the coating liquid obtained as described above was measured in the same manner as in Example 1, and the coating film was evaluated in the same manner as in Example 1.

The results are shown in Table 1.

[0085]

[Comparative Examples 1 to 4] A coating solution was prepared in the same manner as in Examples 1, 2, 4, and 5 except that the coating solution was not deionized, and the ion concentration of the resulting coating solution was determined in Example 1. The coating was evaluated in the same manner as in Example 1 and the same as in Example 1.

The results are shown in Table 2.

[0087]

[Table 1]

[0088]

[Table 2]

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[Procedure amendment]

[Submission date] March 25, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0064

[Correction method] Change

[Correction content]

Table 1 shows the ion concentration of the coating liquid and the above evaluation results. The ion concentration of the coating liquid was measured by the method shown on page 4 .

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0065

[Correction method] Change

[Correction content]

[0065]

Example 2 —Preparation of silica sol— 121.6 g of methyl silicate-51 (SiO ₂ concentration; 51 wt%, manufactured by Tama Chemical Industry Co., Ltd.) in a mixed solution of 203.0 g of pure water and 812.2 g of methanol. After that, 150 g of 5% aqueous ammonia was added over 5 hours while maintaining the temperature of the liquid at 45 ° C. by heating the liquid,
This produced silica particles in the liquid. The liquid after the addition was maintained at the same temperature for 1 hour to age the silica particles in the liquid. Then, the unreacted ethyl silicate, methanol and ammonia contained in the liquid are removed from the liquid containing the silica particles by ultrafiltration, and pure water is added at the same time, and the SiO ₂ concentration is 5% by weight. To obtain a silica sol B in which silica particles having a particle size of 110 Å were dispersed.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0080

[Correction method] Change

[Correction content]

[0080]

Example 5 - Preparation of silica sol - Echirushirike over preparative -28 methyltrimethoxysilane 169.4g and Echirushirike over preparative -28 instead of 266.
A silica sol was prepared in the same manner as in Example 4 except that 3 g was used to obtain silica sol E in which silica particles having a SiO ₂ concentration of 10% by weight and an average particle diameter of 250 Å were dispersed.

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0081

[Correction method] Change

[Correction content]

-Preparation of partial hydrolyzate of alkoxysilane- 227.3 g of methyltrimethoxysilane, ethylsilike
A 28% 357.1 g of ethanol, 175.0 g of ethanol, and 240.0 g of pure water were added to 1% aqueous ammonia to adjust the pH of the mixed solution to 8.5. The mixed solution is heated at 50 ° C. for 2 hours to partially hydrolyze the alkoxysilane.
An aqueous acetic acid solution was added to adjust the pH to 4, and this solution was heated at 50 ° C. for 5 hours to obtain an alkoxysilane partial hydrolyzate e.

Claims (2)

[Claims] 1. The general formula R _n Si (OR ′) _4-n (wherein
R and R'represent an alkyl group having 1 to 8 carbon atoms, an aryl group or a vinyl group, and n is an integer of 0 to 3. ) A silica sol (A) obtained by hydrolytic polycondensation of an alkoxysilane represented by the formula (1), and the alkoxysilane or a partial hydrolyzate thereof (B).
A coating solution for forming a coating film containing a reaction product with the coating liquid, wherein the coating solution has an ion concentration of 1.0 mmol / liter or less. 2. A cation is added to any of a liquid containing at least the silica sol (A), the alkoxysilane or a partial hydrolyzate thereof (B) and a coating liquid for forming a film in the process of producing the coating liquid for forming a film. The film formation according to claim 1, wherein the treatment with the exchange resin and the treatment with the anion exchange resin are carried out to adjust the ion concentration in the obtained coating liquid for film formation to 1.0 mmol / liter or less. For producing coating liquid for use in cosmetics.