JPS58189263A - Coating fluid for sio2 film formation - Google Patents

Abstract

PURPOSE:To provide a coating fluid for SiO2 film formation excellent in storage stability, workability, etc., by incorporating as a principal component hydroxysilane (oligomer) given by the reaction of tetraalkoxysilane with water in the presence of a phosphate in an org. solvent. CONSTITUTION:Tetraalkoxysilane (e.g., tetramethoxysilane, tetraisopropoxysilane) is reacted with water in the presence of a phosphate of formula I or II (wherein R is 1-6C alkyl, aryl) etc. in an org. solvent such as methanol, propylene glycol, or acetone. The resulting hydroxysilane and/or oligomers thereof, as principal components, and, if necessary, org. solvents, surfactants, etc. are blended to give the intended coating fluid for SiO2 film formation. Said coating film can be applied onto substrates such as glass, metallic materials or by roll-coating, offset printing, etc.

Description

[Detailed description of the invention] This invention applies to glass, ceramics, and plastics.

The present invention relates to a coating liquid for forming a 5iOz film on a substrate such as metal.

S i Ot film is widely used as a film to prevent alkali ion elution from the glass of liquid crystal display elements, an alignment control film, a passivation film for ICs, a diffusion film doped with B and P, and a surface-strengthened protective film for glass bottles, etc. has been done.

Vapor phase growth and coating methods are generally known as methods for forming this 5-inch film, but the former requires special equipment and is unsuitable for mass production. In the latter application method.

Large lid production is possible with a simple device, and (1) method using a reaction product of halogenated silane, carboxylic acid, and alcohol (Japanese Patent Publication No. 16488/1988, Japanese Patent Publication No. 16488/1983,
-20825), (2) alkoxysilane,
A method using a product of a lower carboxylic acid and an alcohol (% JP-A-55-34258) has been disclosed. However, in method (1), hydrogen halides and carboxylic acid halides are produced as by-products, and these halogen ions may remain in the coating solution. It has the disadvantage of corroding membranes and equipment. Method (2) can compensate for the drawbacks of (1), but
It requires an equivalent amount of carboxylic acid to the alkoxysilane, and from this carboxylic acid, a carboxylic acid ester is formed and remains in the coating solution.

It has the drawbacks of limited solvent systems and poor storage stability.

The object of the present invention is to produce uniform SiOs without the above-mentioned drawbacks.
The object of the present invention is to provide a coating liquid for forming a film using S i O.

The present invention provides S containing a hydroxysilane and/or an oligomer thereof obtained by reacting a tetraalkoxysilane and water in an organic solvent in the presence of a phosphoric acid ester.
i O, relating to a coating liquid for film formation.

Tetraalkoxysilane does not react when mixed with water, stirred or heated, but when a phosphoric acid ester is added, the reaction progresses with heat generated, making it possible to produce hydroxysilane and/or its oligomer. Phosphoric esters also act as stabilizers for hydroxysilane and/or their oligomers, and those to which phosphoric esters are added are
It does not gel even if left at 0°C for 2 months.

Examples of the tetraalkoxysilane used in the present invention include tetramethoxysilane, tetraethoxysilane, and tetralinepropoxysilane.

Tetrabutoxysilane, tetrapropoxysilane, tetrakis(2-ethylbutoxy)silane.

Tetrakis(2-methoxyethoxy)silane.

Tetraphenoxysilanes, mixtures thereof, oligomers of tetraalkoxysilanes (e.g.

Examples include Colcoat 40) manufactured by Nippon Colcoat Co., Ltd. The tetraalkoxysilane preferably has a tetraalkoxy content in the range of 10% from the viewpoint of practicality of the coating film and stability of the product.
Particularly preferred is a range C of 40 to 40 tqb.

The phosphoric acid ester used in the present invention includes:

(RO)sPO, (RO)sP(OH)t (RO)*
PO (OH).

(RO)PO(OH)□(Ro)sp, (I(o)sp
(OH).

(RO)PO (where R is Al having 1 to 6 carbon atoms, F)
(representing a p group or an ary group).

Particularly preferred are those containing hydroxyl groups in nine molecules.

The amount of the phosphoric acid ester added is preferably in the range of 0.01 to 10% by weight based on the tetraalkoxysilane in view of the effect of the addition of the phosphoric ester, S t O, and the properties of the film formed.

The organic solvent used in the present invention is methanol.

Ethanol, alcoholic acid, isopropyl alcohol, butyl alcohol, methyl cellosolve, ethyl cellosolve.

Cellosolves such as butylselonorp, carpitols such as methylcarpitol, ethylcarpitol, butylcarpitol, ethylene glycol, propylene glycol. Polyalcohols such as diethylene glycol and glycerin, esters such as methyl acetate, ethyl acetate, and butyl acetate, acetone, and methyl ethyl ketone.

Ketones such as acetylacetone, N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, dimethyl sulfoxide, etc. can be used, and mixtures thereof can be used. In particular, solvents containing alcohols, cellosolves, and calpitols as main components can be used. preferable. In addition, as organic solvents 5-, seronlupes, calpitols, N-
It is recommended to use methyl-2-pyrrolidone, dimethylacetamide, etc. as a solvent.

Since the drying speed of the coating film when the coating liquid is applied can be slowed down, coating methods such as Cicaroll Coater 9 flexo printing and offset printing, which provide good leveling of the coating film, can be used.

The water added in the present invention is preferably distilled water or ion-exchanged water, and the amount used is 1 mo of tetraalkoxysilane.
4 mol per liter is preferable.

If the amount is less than this, the condensation reaction of hydroxysilane will proceed and there is a tendency to produce insoluble matter. If it is more than this, unreacted water will remain in the reaction product, making it difficult for the coating solution to wet the substrate. affect.

The wettability tends to be poor.

In the method for producing silane and/or its oligomer in the present invention, it is preferable that tetraalcoxin 2 is present.

The reaction temperature is preferably from room temperature to 100°C, and if it is higher than this, gelation tends to occur.The reaction time for the alkoxysilane and water is preferably 0.5 to 5 hours.

The coating solution for forming a Sin film according to the present invention may be a composition obtained by reacting the above-mentioned coating material in an organic solvent, or may be prepared by adding the same or other organic solvent to the coating solution. You can also use it as In some cases, part of the organic solvent in the composition obtained by reacting the above materials may be removed.

S10 according to the present invention. In order to improve the wettability of the film-forming coating liquid to the substrate, it is also possible to add a surfactant. As a surfactant.

Nonionic surfactants are preferred. ! ,Ta. To change the properties of the film to Si, I P 1 B @ As + G
It is also possible to add compounds such as Flgsb, 'ri, In, A/, etc.

S i (% S using the coating liquid for film formation) according to the present invention
To form a film, the coating solution is preferably coated at room temperature by a conventionally disclosed method, such as a spinner method, a dipping/pulling method, a brush coating method, or flexographic printing.

This is carried out by applying the coating onto a substrate using a roll coater, offset printing, etc., and heat-treating preferably at 200 to 800°C. If the heat treatment temperature is low, Sin,
The hardness of the film is poor, and the higher the heat treatment temperature, the higher the hardness.
in, a membrane can be obtained. Examples of the substrate include plates and molded products made of glass, ceramic, plastic, metal, and the like.

The present invention will be explained below with reference to Examples.

Example 1 Tetraethoxysilane 23f and ethyl alcohol 68.
Add 0.177 of diethyl phosphate to the 88f mixture.

Furthermore, when 7.95 p of ion-exchanged water was added while stirring, the reaction occurred with an exotherm of about 10°C, and after about 3 hours of reaction, the amount remaining after heating was 9.0% by weight at 150°C.

It showed 7.0% by weight at 500°C. When this was coated on a glass substrate by dip coating at a pulling speed of 20 cm/mjn and baked at 500°C, a highly hard coating with a thickness of 9M and about 200 o'A could be obtained. Moreover, no gelation was observed even when this coating liquid was left in a constant temperature bath at 40° C. for 2 months.

Example 2 A mixture of 29.25 L of tetraisopropoxysilane and 62.62 F of propyl alcohol was mixed with 0.00 g of diptyl phosphate.
Add 23P. 7. Add ion-exchanged water while stirring.
When 959- is added, the reaction occurs with an exotherm of about 8°C.

The remaining amount of heating after about 5 hours of reaction is 9.5 at 150℃/30 minutes.
It showed 7.2% by weight at 500°C/30 minutes. Coat this on a glass substrate with a spinner at 4000 rpm, and
When fired at 00°C, a highly hard film with a thickness of 200 OA could be obtained. Furthermore, no gelation was observed even when this coating solution was placed in a constant temperature bath at 40° C. and left for two months.

Example 3 A mixture of 23 f of tetraethoxysilane, 6 fl of N-methyl-2-pyrrolidone, and 88 P was mixed with 0.0 ml of diethyl phosphate.
When 17 P was added and 7.951 ml of water was added with further stirring, the reaction occurred with an exotherm of about 15°C, and the amount remaining after 3 hours of reaction was 9.7% by weight at 150°C/30 minutes.

At 500°C/30 minutes, 7.2 folds of 1lii- were exhibited. When this was coated on a -9= glass substrate using a roll coater and baked at 500'C, a highly hard film with a film thickness of 220 oA could be obtained. Furthermore, no gelation was observed even when this coating solution was placed in a constant temperature bath at 40° C. and left for two months.

Comparative Example 1 Tetraethoxysilane 23p, ethyl alcohol 63p.
09 Added 5.97 p of acetic anhydride to the P mixture.

While stirring, water was added (7.95%).

No heat generation was observed, and 150" (,73
The remaining heating amount at 0 minutes was 0.95 weight fts. There it was. However, when this coating solution was left in a constant temperature bath at 40° C., gelation was observed within one month.

The coating solution for forming a SiOx film according to the present invention has excellent storage stability, and when a high boiling point solvent is used, it can be used with a roll coater or flexographic printing, making pattern formation easy. I can do it.

Procedural amendment (voluntary) June 116, 1980 1.1f Public Prosecutor's Office 1, Indication of the case 1982, (l'-1, ν Permit No. 277 No. 2 Title of invention 5102 Coating for film formation Solution 3: Relationship with background f'l to be amended Name of patent applicant: f44
fil II) r, Hisei 1-Sai Co., Ltd. 4, agent
Person 5 correction glue 1g! Contents of amendment in Column 6 of Detailed Description of the Invention of the Specification 1) r (RO)2P in the 5th line from the bottom of page 4 of the specification of the present application
(OH) F (RO) 2P (OT
-I), correct it as -L.

that's all

Claims (1)

[Claims] 1. Si containing hydroxysilane and/or its oligomer obtained by reacting tetraalkoxysilane and water in the presence of a phosphoric acid ester in an organic solvent
Coating liquid for forming Ox film. 2. S according to claim 1, wherein the phosphoric ester is a phosphoric ester having a hydroxyl group in the molecule.
i Coating liquid for Ox film formation.