JPS5958054A - Silicone resin solution and its preparation - Google Patents

Abstract

PURPOSE:To obtain a resin solution useful as an insulating material of a semiconductor having improved shelf stability from which a very small amount of hydrochloric acid is removed, by dissolving a polycondensate prepared by hydrolyzing a tetraalkoxysilane and subjecting it to polycondensation and a polysilsesquioxane prepolymer in a specific organic solvent, treating the polycondensate under reduced pressure. CONSTITUTION:A polycondensate obtained by hydrolyzing a tetraalkoxysilane and subjecting it to polycondensation and a polysilsesquioxane prepolymer are dissolved in an organic solvent having >=110 deg.C boiling point are dissolved, and treated under reduced pressure at <=5mm.Hg, preferably at <=3mm.Hg, to give a resin solution having <=10ppm content of a hydrogen halide. Or the polycondensate obtained after the hydrolysis of the monomer is dissolved in the solvent, treated in reduced pressure, and blended with the polysilsesquioxane prepolymer or a solution of the polysilsesquioxane prepolymer in an organic solvent and dissolved in it. Treatment under reduced pressure is carried out at <=40 deg.C, preferably at 5-28 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a silicone resin solution for coating and a method for producing the same. (2) Background of the technology and problems with the prior art Hydrolyzed polymer of tetraalkoxysilane (PDAS)
A mixed solution of the solution and a hydrolyzate of alkyltrialkoxysilane (JP-A-48-81928, or JP-A-48-81928)
26822) is used, for example, as a protective material for the surface m1 of plastics, and is a useful resin composition solution. Furthermore, by mixing the PDAS solution with a solution of polysilsesquioxane prepolymer (hereinafter referred to as PLO8 (abbreviation of polylada organosiloxane)) or a solution, the composite resin solution can be treated at a high temperature of 300°C or higher after application. It is used as an insulating material between protective layers such as half fences, bubble memories, etc. (Japanese Patent Laid-Open No. 54-171005
) Also, by using cellosolve acetates such as butyl cellosolve acetate, ethyl cellolyl acetate, and butanol as the organic solvent used in the above mixed solution, a uniform coating film can be obtained with a spin cord (Japanese Patent Application No. 55-158114).

Devices that are likely to suffer from electrolytic corrosion, such as semi-solid or bubble memory, should be used at high altitudes. Even if the insulating material used therein contains WI amount of impurities, it may cause electrical corrosion defects.

In addition, To permalloy such as Fe2O3 is corroded by acid.
When used to protect fragile membranes, the inclusion of a trace amount of acid may not be fatal. Therefore, the presence of even a small amount of acid in the insulating material is not allowed.

Trace amounts of acid are present in the reaction steps described below. 1, that is, a hydrolyzed condensation polymer solution of tetraalkoxysilane s+(oR)4 [where R is an alkyl group] is generally obtained according to the reaction of the following formulas (1) and (2): St
(OR)4+2H,O→ S I (OR) t (OH)! +2ROM
(1) nsi(OR)1 (OH)2 → l0-(: SI (OR)tO+, H+(n-1)H
,0(2)In addition to the reaction of equation (2), a membrane alcohol condensation reaction also occurs! Ill hook it.

and tl et al.'s anti-btu;
Since it contains a 5i-OH group in addition to the -OH group, it is easy to cause a three-dimensional crosslinking reaction even if it is left alone, so it is often removed using a measuring scale F11 in an alcohol solvent. 005 to 05% acid is added to the silane monomer as an accelerator for the reaction in formula (2).As the acid, hydrochloric acid is used as it evaporates and is removed when the coating film is heat treated. It appears that almost all of this hydrochloric acid has been volatilized and removed, and even if a mixed solution of PDAS and PLOS polymer is directly applied on the aluminum wiring for 4 hours, no electrolytic corrosion of the aluminum is detected. However, when a long-term bias test was conducted, it was found that one person had poor eating habits.

It was thought that the problem was caused by the extremely harmful hydrochloric acid that could not be removed. This is because electrolytic corrosion defects were reduced by removing as much hydrochloric acid from the resin liquid as possible.
1. Removal of water-soluble uncombined substances in the fat solution is carried out by washing with water. However, in the case of a mixed solution of PDAS and PLOS prepolymers, this is difficult.

Why is S 1-OH in PDAS not 8l-OH?
It is easy to change into a base, and if too much SlO■■ is present, it may gel or lose its storage stability and become a gel. Furthermore, PDAS, PT, and OS are distributed in the washing water layer, probably due to the organic solvent that dissolves in the water during washing to remove hydrochloric acid. When a water-miscible solvent such as ethanol is used as the organic solvent, washing with water itself is impossible and gelation occurs immediately. It cannot be used in solvents that are difficult to mix with water, such as benzene, because PDAS and PLO8 are too easily dissolved. Further, to remove volatile impurities, for example, in order to improve the purity of the solvent, a method of heating and separating by distillation is adopted, but this method is also not applicable to PDA, S solutions. This is because gelation becomes easier as the molecular weight increases.

Pvhbl. Since L alone is unstable and gels in a short period of time, it must always be dissolved in the frame solvent. The solvent must also have such a vapor pressure that a large portion of the hydrochloric acid remains even after it has been removed.

(3) Object and Structure of the Invention The object of the present invention is to solve these conventional problems and provide a silicone resin solution that is stable in storage, from which trace amounts of hydrochloric acid have been removed, and a method for producing the same. shall be.

That is, the silicone resin solution of the present invention has a boiling point of 110
Hydrogen halide-containing 101)I) made by dissolving a hydrolyzed condensation polymer of tetraalkoxysilane and a polysilsesquioxane prepolymer in an organic solvent having a temperature of ℃ or above.
m or less is considered a threat. Furthermore, a method for producing a silicone resin solution according to another invention is to mix a hydrolyzed condensation polymer solution of tetraalkoxysilane, a polysilsesquioxane prepolymer, and an organic solvent having a boiling point of 110° C. or higher, and then heat the mixture under a pressure of 5 wHgLJ. It is characterized by being treated under reduced pressure under reduced pressure, or alternatively, a hydrolyzed polymer of tetraalkoxysilane is dissolved in an organic solvent with a boiling point of 110°C or higher, and the resulting solution is sm
It is characterized in that the treatment is carried out under a reduced pressure of HgJJ, and a polysilsesquioxane prepolymer or an organic solvent solution of a polysilsesquioxane prepolymer is further mixed and dissolved in the treatment solution.

The PLO8 (polysilsesquioxane) prepolymer used in the present invention is not particularly limited.
, into a starting monomer and t,..., n sugar ces as a starting monomer, and after adding a hydrochloric acid acceptor such as triethylamine to j+n. Add water, convert to R'3i(OH)s, heat, condensate and polymerize, wash with water and concentrate.
Unless a precipitant such as methanol is added, it can be easily obtained as a white powder of F(O+FJ!S iO+,s +T,lH).

In addition, when R sugar (OR)s is used as a starting monomer, MI
Add a hydrochloric acid aqueous solution dissolved in BK, heat aggregate, and concentrate and remove the water-washed MIBK. Ro-+ R's becomes a white powder.
101. a When you get 9R, you can make a sword. Or, R
A small amount of alcohol and an aqueous hydrochloric acid solution are added to 'S i (OR)s, heated, and the alcohol, hydrochloric acid, and water are removed by evaporation, and polymerization is then carried out. In this case no cleaning is necessary.

The molecular structure of the PLO8 prepolymer obtained by the above polymerization method using R'S S (u) as a starting monomer has a relatively complete ladder structure as shown in formula (3) (% 53-88099) R'5i (O
The molecular structure of the PLOS prepolymer obtained by the above polymerization method using R) as a starting monomer has a partially ladder structure as shown by formula (4) (Shibe Takeda et al., Chemical Society of Japan). Proceedings of the 44th Autumn Annual Meeting 11.582 (Showa 56).

(R' is a relatively small hydrocarbon group such as methyl, ethyl, and propyl butyl, but R' is a monovalent organic group such as methyl, ethyl, vinyl, propyl, and phenyl. Legs m and n are positive integers, and mt
j: often a small number of 10 or less including 0) and straw P T,, The mixing ratio of the OS prepolymer and PDAS is not particularly limited. This is because, regardless of the mixing ratio, the PDAS solution contains hydrochloric acid, which needs to be removed.

As the organic solvent used in the present invention, any solvent can be used as long as it dissolves PDAS and has a boiling point of 110° C. or higher, such as alcohol, cellosolve acetate, ketone, ether, and cellosolve gas.

For example, n-butanol (117,7°C), n-amyl alcohol (138,3°C), n-hexanol (15
7,9℃), n-buty7t, ether (140,9℃)
, shrimp chlorohydrin (117℃), methyl-n-butyl ketone (127.2℃) methyl cellosolve acetate)
(144.5-145.1°C) etc. are mentioned as an example. Note that the fact that a solvent with a high boiling point has a low evaporation rate at room temperature does not mean that there is a difference in weight. It is advantageous to use a solvent with a high boiling point as the solvent used in the present invention. For example, when comparing methyl cellosolve acetate, ethyl ecep solp acetate, and butyl cellosolve acetate, the boiling points are 1445-145.1℃ and 1563℃, respectively.
℃, 191.5℃ (according to "Solvent Handbook" edited by Asahara et al., Kodansha, published in 1975),! l) When hydrochloric acid in an ethyl alcohol solution of PDAS containing 0.1% HC, t3 is treated under reduced pressure to a level K that cannot be detected even with silver nitrate, the remaining cellosolve acetate is Tokyo: 48% and 76%, respectively.
%, 90%. Of course, it is possible to compensate for the liquid gap by adding. Solvents with too high a boiling point, such as 2-phenoxyethyl acetate (boiling point 2
597°C), which may be advantageous during vacuum treatment, but the solvent left in the film during coating and curing may cause pinholes to form over time. In the present invention, it is also possible to use a mixed solvent; for example, a solvent such as toluene or xylene that does not dissolve PDAS alone may be used in combination with an alcoholic solvent such as n-butyl alcohol.

For example, in the case of n-butyl alcohol/xylene mixed solvent, it can be used in the range of 1010 to 8/2 in terms of weight ratio, and in the case of n-butyl alcohol/tene-based mixed solvent, it can be used in the range of 1010 to 6/4. It can be used within the range of. However, these ranges vary somewhat depending on the concentration of the PDAS stock solution and the concentration of PDAS after the reduced pressure treatment. This is thought to be due to the fact that xylene has a wider range than that of Remotolue 7 (D), which causes more volatilization during depressurization treatment.

In the present invention, the lower the pressure during the reduced pressure treatment of the mixed resin solution, the more advantageous it is because the treatment can be carried out in the shortest possible time.
3 tn ) Ig II or lower is preferred. But 0.5I
! It is actually usable even if it is more than l1lIg. High humidity during depressurization treatment can be disturbed and controlled in a short time, but PT)A
In order to avoid the V quality of s, it is necessary to carry out the process at 40°C or lower.

The temperature is preferably 28°C or lower and 5°C or higher.

The amount of PDAS solution to be treated during the wave pressure treatment required, P
Although it cannot be generally specified because it depends on the concentration of hydrochloric acid contained in the DAS solution, continuous depressurization treatment can be carried out using, for example, a rotary evaporator. In that case, the required processing time depends on the angle of the rotary evaporator, the number of revolutions, the shape and size of the flask, etc.

By performing the depressurization process in this way, the PDA
It is possible to lower the hydrochloric acid concentration in the S solution to a level that cannot be detected using silver nitrate, and is estimated to be less than 1 ppm. In other words, the measurement limit is at least lQpp.
It was not detected by the analytical method of m.

(4) Examples of the invention The present invention will be further explained below with reference to Examples.

Example 1 Weight average molecular weight (hereinafter, M%V value converted to standard polystyrene by Nigel permutation chromatography), the functional groups are methoxy and silanol, and the molar ratio is about 2
It contains 11.4% by weight of PDAS, which is 1:1, and the solvent is a mixture of methyl ethyl ketone and methyl alcohol (mixing ratio is about 7:3 by weight), and PDAS containing 0.05% by weight of hydrochloric acid. 1,100 g of the solution, 20" g of butyl cellosolve acetate, and 6 g of n-butyl alcohol were collected in an eggplant-shaped flask. This eggplant-shaped flask was connected to a rotary evaporator and set at an angle of 45 degrees.
It was rotated at a rotation speed of 6 Orpm. The flask was then placed in a water bath with a bath temperature of 25° C., and the pressure was reduced to 2.0 Ow+Hg using a vacuum pump, and the pressure was treated under reduced pressure for 4 hours. 86.1g of solvent was trapped in the trap using ethanol cooled with dry ice as a refrigerant, and the concentration of the solution in the Nasugata flask was 9.
It was 84g. Add 1.6 g of butyl cellosolve acetate to make PDAS solution-11.

Into this PDAS solution (2), a PLOS prepolymer with Min of 1060 (') and R' expressed by the formula (4) is added.
is methyl, R is ethyl and silanol, and the ratio is about 1%N
, 1.4 g of PLO8 with an average value of 2.1 and 5.8 g of butyl alcohol were added and dissolved.
S-1) LO8 mixed solution was obtained.

Pour 1 g of this PDAS-PLO8 mixture into a recording tube.
．． When 2 g of a 1% silver nitrate solution was shaken, a white gelled substance eventually formed on the 9 walls of the organic layer, but the aqueous layer had the brownish color of the rented silver, but no white precipitate. There was no. The PllAS-PLO8fli liquid was extracted and washed with water, and the detection limit was 10 pp.
m or less.

A pr, os brevolimer represented by the formula (4) where i is 6500, R' is methyl and phenyl in a molar ratio of 2:1, the average value of m is 34, and R is enoxy The molar ratio of t-silanol is 1f! +2 to 1 P, LO8
Pour 31 g of XPDAS melt into 2 + 10 g and 93 g of a mixed solvent of butyl cellosolve aceput and butyl cellosolve aceput (mixing ratio is 1:1 in diluted η゛) into a 11-well eggplant-shaped flask, and after dissolving M, process in the same manner as in Example 1. did. However, the solution in the flask was 130 g, which was treated under reduced pressure at a rotational speed of 32 rpm, and 25 g of methyl cellosolve acetate was added to drain the PDAS-PLO8 mixture. Detection of chlorine in this liquid was carried out in the same manner as in Example 1, but the amount of chlorine in the liquid was very low.

patent applicant Fujimae Co., Ltd. patent application agent Patent attorney Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney Yukio Uchida Keiri Mt. fl [, r 357-

Claims (1)

[Scope of Claims] 1. Hydrogen halide containing 10 ppm obtained by dissolving a hydrolyzed condensation polymer of tetraalkoxysilane and a polysilsesquioxane prepolymer in an organic solvent having a boiling point of 11011 or more. Silicone resin solution below a. 2. Mixing a solution of a hydrolyzed condensation polymer of tetraalkoxysilane, a polysilsesquioxane prepolymer, and a specific solvent having a boiling point of 0°C or higher, and subjecting the mixture to vacuum treatment under a pressure of 5+nn+Hg or less is 1+! i9. A method for producing a silicone resin solution as b. 3. Dissolve a hydrolyzed condensation polymer of tetraalkoxysilane in a specific solvent having a boiling point of 110° C. or higher, treat the resulting solution under reduced pressure at a pressure of 5 rv +) Hg or less, and add polysilsesquioxide to the treated solution. A method for producing a silicone resin solution, which involves mixing and dissolving a solvent solution of sample polymer or polysilsesquioxane prepolymer.