JPH09111187A - Silicone varnish, its production, and prepreg impregnated with silicone varnish - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a highly heat-resistant silicone varnish having a good shelf stability and an excellent curability (reactivity) and a prepreg impregnated with the silicone varnish. SOLUTION: This varnish consists of a silicone oligomer (A) having an intrinsic viscosity at 25 deg.C of 0.1-10cm<3> /g and obtained by the condensation through dehydration by heating of a dialkoxysilane having one or two kinds of groups selected among phenyl and 1-3C alkyl groups and having 1-4C alkoxy groups, a phenyltrialkoxysilane or a methyltrialkoxysilane having 1-4C alkoxy groups, an inorganic acid that does not contain metal and contains at least one of chlorine atom and phosphorus atom or an organic acid having a PKa value of 0.8 to 6, and water or a solvent mixture comprising water and a water-soluble organic solvent except an aliphatic monohydric alcohol, a component (B) comprising an aliphatic monohydric alcohol or a solvent mixture containing it, and a condensation catalyst (C) containing a metal atom.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention has a continuous heat resistance of 300 ° C. or higher, is excellent in flexibility and moldability, and therefore has a coating agent, a laminated plate, a heat insulating material, a protective material, a molded body, an interlayer insulating film. Belongs to the technical field of producing and using a silicone varnish that can be used as a material for a printed circuit board and an impregnated prepreg using the same.

[0002]

2. Description of the Related Art In the case of conventional organic materials, continuous heat resistance of 300 ° C. or higher cannot be obtained. On the other hand, in the case of inorganic materials, baking at 1000 ° C. or higher is required to obtain the inorganic material. Since it lacks flexibility, the bending strength is weak even if it is made into a composite.

As a method for improving the drawbacks of the above-mentioned inorganic materials, many examples of synthesizing an inorganic polymer by using polycondensation of alkoxysilane have been disclosed (for example, Japanese Patent Laid-Open No. 4-204).
No. 65477, No. 4-106172, No. 6-240143, and No. 63-278.
977).

On the other hand, coating agents in which bifunctional and trifunctional alkoxysilanes are combined are well known in the art, and the amount of residual silanol groups can be controlled by adjusting the polycondensation reaction during the production of this coating agent. It is known that the viscosity can be adjusted by adjusting the viscosity (for example, JP-A-2-254976 and JP-A-4-180977).

In this case, as the polycondensation reaction catalyst, an alkoxytitanium or an organic acid metal salt having a strong condensation accelerating ability is used as seen in JP-A-2-284976.

[0006]

However, when a polycondensation catalyst having a strong ability to accelerate polycondensation is used, gelation is likely to occur during polycondensation while adjusting the amount of silanol groups. Further, if the catalyst is still contained, the storage stability is poor, and it must be neutralized and removed. Therefore,
Currently commercially available products having a high molecular weight are of a type in which a polycondensation catalyst is added immediately before use.

On the other hand, when a catalyst such as hydrochloric acid or phosphoric acid having a relatively weak ability to accelerate condensation is used, the storage stability of the varnish is good but the curing speed is slow and the network formation does not proceed sufficiently.

The present invention provides a highly heat-resistant silicone varnish whose viscosity can be easily adjusted during gel condensation polymerization, gelation hardly occurs, storage stability is good, and curability (reactivity) is excellent, and a composite material using the same. , To provide a printed circuit board.

[0009]

Means for Solving the Problems As a result of intensive studies made by the present inventors in order to improve the above-mentioned problems, as a result of obtaining a monomer having a predetermined viscosity without causing gelation during the condensation polymerization of alkoxysilane, a monomer It has been found that it is preferable to use a blend of bifunctional and trifunctional alkoxysilanes as the solvent, a water-soluble organic solvent excluding the aliphatic monohydric alcohol as the solvent, and a metal-free hydrolytic acid catalyst as the catalyst. .

After obtaining a desired viscosity, it is preferable to add an organic solvent containing an aliphatic monohydric alcohol solvent from the viewpoint of storage stability. To accelerate curing, a hydrolyzed acid containing no metal is used. It has been found that the catalyst alone is insufficient, and the addition of an organic acid metal salt or titanium alkoxide is effective.

The present invention has been made based on the above findings, and has (A) (1) a phenyl group and one or two kinds of alkyl groups having 1 to 3 carbon atoms, and Dialkoxysilane having 1 to 4 alkoxy groups, (2) carbon number 1
Phenyltrialkoxysilane or methyltrialkoxysilane having an alkoxy group of ~ 4, (3) an inorganic acid not containing a metal and containing at least one kind of chlorine atom and phosphorus atom, or having a PKa value of 0.8 to 6 Some organic acids,
And (4) the intrinsic viscosity at 25 ° C. obtained by dehydration condensation of water or a mixture of water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol under heating is 0.1 to 10 c.
m ³ / g of a silicone oligomer, (B) an aliphatic monohydric alcohol or a mixed solvent containing the same, and (C) a silicone varnish comprising a condensation catalyst containing a metal atom (claim 1), water or water and an aliphatic The silicone varnish according to claim 1, wherein the solvent (4) consisting of a water-soluble organic solvent excluding the monohydric alcohol is a glycol ether-containing solvent (claim 2), containing no metal and having a small amount of chlorine atoms and phosphorus atoms. Inorganic acid or PKa containing both
The organic acid (3) having a value of 0.8 to 6 is phosphoric acid, hydrochloric acid,
Oxalic acid, acetic acid or formic acid, The silicone varnish according to claim 1 or 2 (claim 3), the condensation catalyst (C) containing a metal atom is an organic acid tin salt, an organic acid lead salt, an organic acid cobalt salt, an organic acid. Acid zinc salt, organic acid manganese salt, organic acid iron salt, or alkoxy group having 1 to 4 carbon atoms or 1 to 1 carbon atom
4. The silicone varnish according to claim 1, 2 or 3, which is a monotitanium compound containing an alkoxy group and an acetoxy group of 4, and the organic acid is heptanoic acid, octanoic acid, nonanoic acid or naphthenic acid (claim 4). A silicone varnish-impregnated prepreg obtained by impregnating a reinforcing cloth, a non-woven fabric or a filament with the silicone varnish according to 1, 2, 3 or 4 and drying it until tack-free (claim 5),
A composite material obtained by stacking a plurality of silicone varnish-impregnated prepregs according to claim 5 and thermosetting them (claim 6),
A composite material obtained by covering or winding a silicone varnish-impregnated prepreg according to claim 5 on a base material and thermally curing the same (claim 7), and a printed board having a metal layer provided on both or one side of the composite material according to claim 6. A laminated board for use (claim 8), 2 to 15 printed boards having a circuit formed on one side or both sides produced using the laminated board for a printed board according to claim 8, and an interlayer according to claim 5. A printed board having a multilayer structure obtained by sandwiching a silicone varnish impregnated prepreg and performing hot press molding (claim 9), the silicone varnish according to claim 1, 2, 3 or 4, and an inorganic powder, particles or whiskers. A composite molded article obtained by molding a film-like material obtained by heating and desolvating the mixture, or crushing a solid (claim 10),
A build-up multilayer substrate for an electronic circuit module using the cured product of the silicone varnish according to any one of claims 1, 2, 3 or 4 (claim 11), (A) (1) a phenyl group and 1 to 3 carbon atoms. A dialkoxysilane having one or two of the above alkyl groups and having an alkoxy group having 1 to 4 carbon atoms, (2) having 1 carbon atom
Phenyltrialkoxysilane or methyltrialkoxysilane having an alkoxy group of ~ 4, (3) an inorganic acid not containing a metal and containing at least one kind of chlorine atom and phosphorus atom, or having a PKa value of 0.8 to 6 Some organic acids,
And (4) the intrinsic viscosity at 25 ° C. obtained by dehydration condensation of water or a mixture of water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol under heating is 0.1 to 10 c.
A method for producing a silicone varnish, which comprises adding (B) an aliphatic monohydric alcohol or a mixed solvent containing the same and (C) a condensation catalyst containing a metal atom after obtaining m ³ / g of a silicone oligomer (claim 12). ), Water or a solvent (4) comprising water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol is a glycol ether solvent (claim 13), a method for producing a silicone varnish (claim 13), containing no metal And at least 1 of chlorine and phosphorus atoms
The method for producing a silicone varnish according to claim 12 or 13, wherein the inorganic acid containing a seed or the organic acid (3) having a PKa value of 0.8 to 6 is phosphoric acid, hydrochloric acid, oxalic acid, acetic acid or formic acid. 14), the condensation catalyst (C) containing a metal atom is
Organic acid tin salt, organic acid lead salt, organic acid cobalt salt, organic acid zinc salt, organic acid manganese salt, organic acid iron salt or carbon number 1
A monotitanium compound containing an alkoxy group having 4 to 4 or an alkoxy group having 1 to 4 carbon atoms and an acetoxy group,
The method for producing a silicone varnish according to claim 12, 13 or 14 (claim 15), and claim 1, wherein the organic acid is heptanoic acid, octanoic acid, nonanoic acid or naphthenic acid.
Silicone varnish according to 2, 3 or 4 and an inorganic powder,
A method for producing a composite molded article, which comprises heating a mixture of particles or whiskers to remove the solvent and crushing the obtained film-like material or a solid, and molding the mixture by a hot press or a molding machine (claim 16). ) Concerning.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The silicone oligomer (A) contained in the silicone varnish of the present invention comprises (1) a phenyl group and an alkyl group having 1 to 3 carbon atoms (specifically, a methyl group, an ethyl group, an ethyl group, Propyl group) and one or two of them, and a dialkoxysilane having an alkoxy group having 1 to 4 carbon atoms (specifically, methoxy group, ethoxy group, propoxy group, butoxy group), (2) carbon Number 1-4
Alkoxy group (specifically, methoxy group, ethoxy group,
Phenyltrialkoxysilane or methyltrialkoxysilane having a propoxy group, butoxy group),
(3) an inorganic acid containing no metal and at least one kind of chlorine atom and phosphorus atom, or an organic acid having a PKa value of 0.8 to 6, and (4) water or water and an aliphatic monohydric alcohol Is a silicone oligomer having an intrinsic viscosity of 0.1 to 10 cm ³ / g at 25 ° C., which is obtained by dehydration condensation of a mixture of a solvent consisting of a water-soluble organic solvent except the above.

The dialkoxysilane (1) having one or two kinds of the phenyl group and the alkyl group having 1 to 3 carbon atoms and having the alkoxy group having 1 to 4 carbon atoms has 1 to 2 carbon atoms. It is a component that reacts with phenyltrialkoxysilane or methyltrialkoxysilane (hereinafter, also referred to as phenyl or methyltrialkoxysilane) having an alkoxy group of 4 (2) to form a silicone oligomer, and a dialkoxysilane is contained in the silicone oligomer. Since the unit derived from (1) is present, flexibility is imparted to the cured product and mechanical strength is increased.
Since a unit derived from phenyl or methyltrialkoxysilane (2) is present in the silicone oligomer,
Since the heat resistance is improved and the cured product has a branched structure, it becomes solid at room temperature after drying. Further, unlike the case where the system contains a tetrafunctional alkoxysilane, gelation does not occur rapidly, so that the polycondensation reaction can be easily controlled.

Specific examples of dialkoxysilane (1) include dimethyldialkoxysilane, phenylmethyldialkoxysilane, methyl n-propyldialkoxysilane, ethylmethyldialkoxysilane and ethylphenyldialkoxysilane. The alkoxy group is preferably a methoxy group, an ethoxy group or a propoxy group. The hydrolyzable strength is in this order. These dialkoxysilanes may be used alone or in combination of two or more. Of these, dimethyldialkoxysilane and phenylmethyldialkoxysilane are preferable from the viewpoint of improving heat resistance, and methyl n-propylalkoxysilane and ethylmethyldialkoxysilane are preferable from the viewpoint of improving flexibility.

Specific examples of phenyl or methyltrialkoxysilane (2) include phenyltrimethoxysilane, phenyltriethoxysilane, methyltrimethoxysilane, and methyltriethoxysilane. These may be used alone or in combination of two or more. Of these, phenyltrimethoxysilane and methyltrimethoxysilane are preferable because they have a high hydrolysis rate and are effective in improving the heat resistance of the cured product.

The inorganic acid containing no metal and containing at least one of chlorine and phosphorus atoms or the organic acid (3) having a PKa value of 0.8 to 6 is dialkoxysilane (1) and phenyl. Alternatively, it is a catalyst used for promoting the hydrolysis of the methyltrialkoxysilane (2) (hydrolysis of an alkoxy group) to form a silanol group. An inorganic acid containing no metal and at least one kind of chlorine atom and phosphorus atom or an organic acid (3) having a PKa value of 0.8 to 6 is difficult to form a network, so that the reaction condition is suitable, for example, 100 ° C. , 14 hours or 15
If the conditions are 0 ° C. and 6 hours, the alkoxysilane can be polycondensed with almost no gelation.

An acid having a PKa value of less than 0.8 has a low effect of promoting hydrolysis, so that the rate of hydrolysis of alkoxysilane is slow and is not practical. In addition, an organic acid having a PKa value of more than 6.0 is effective in accelerating the hydrolysis rate, but has a large ability to accelerate the polycondensation of silanol groups, so that gelation occurs immediately in the varnish manufacturing process, and the molecular weight is increased. (Intrinsic viscosity) cannot be increased. It is unclear why an inorganic acid containing at least one kind of chlorine atom and phosphorus atom is preferable, but such a result is obtained as an experimental result.

An inorganic acid containing no metal and containing at least one kind of chlorine atom and phosphorus atom, or having a PKa value of 0.8.
Specific examples of the organic acid (3) which is ˜6 include phosphoric acid, hydrochloric acid, oxalic acid, acetic acid, formic acid and the like. These may be used alone or in combination of two or more. Of these, phosphoric acid, oxalic acid, and acetic acid are preferable from the viewpoint of preventing gelation.

Other examples of the hydrolysis catalyst include sulfuric acid, sulfonic acid, nitric acid and the like. These have a strong hydrolyzing power, but the accelerating power of the polycondensation reaction is too strong. It is difficult to control the polycondensation reaction, and as a result, it easily gels in the reaction vessel and cannot be used. Hydrochloric acid preferably used in the present invention also tends to be gelated as described above, but at low temperature (about 100 ° C or lower)
By causing the polycondensation reaction to occur, gelation can be avoided.

The solvent (4) consisting of water or water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol is dialkoxysilane (1) and phenyl or methyltrialkoxysilane (2) containing no metal and A solvent used when forming a silicone oligomer by hydrolysis with an inorganic acid containing at least one kind of chlorine atom and phosphorus atom or an organic acid (3) having a PKa value of 0.8 to 6,
It is preferable to dissolve these components, and it is preferable that the dialkoxysilane (1) and the phenyl or methyltrialkoxysilane (2) are hydrolyzed, and that those obtained by polycondensation of these are dissolved. preferable. When such a solvent (4) comprising water or water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol is used, the OH group contained in the solvent does not inhibit polycondensation, and Since the alkoxysilane after hydrolysis and the oligomer after condensation polymerization are dissolved, condensation polymerization proceeds in a homogeneous system, and as a result, a uniform target product is obtained.

In these polycondensation reactions, the aliphatic monohydric alcohol exhibits basicity and easily nucleophilically attacks the Si group of the silanol group, so that the polycondensation of silanol groups is prevented. On the other hand, a dihydric or higher alcohol is suitable as a polycondensation solvent because it is difficult to exhibit basicity because atoms are attracted in both directions and hardly interferes with polycondensation of silanol groups.

Specific examples of the water-soluble organic solvent excluding the aliphatic monohydric alcohol include methyl cellosolve, ethyl cellosolve, ethylene glycol isopropyl ether,
Butyl cellosolve, carbitol, butyl carbitol, diethylene glycol acetate, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, methoxymethoxyethanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, glycol ether solvents such as ethylene glycol monoacetate, Examples thereof include glycol solvents such as ethylene glycol, tetraethylene glycol, propylene glycol and dipropylene glycol, nitrogen-containing solvents such as N-methylpyrrolidone, dimethylformamide and dimethylacetamide, and dimethylsulfoxide. When these are used, they may be used alone or in combination of two or more. Of these, glycol ether solvents are preferred because of their good solubility in hydrolyzed alkoxysilanes and their condensates.

Instead of the water-soluble organic solvent excluding the aliphatic monohydric alcohol in the solvent (4) consisting of water or water and the water-soluble organic solvent excluding the aliphatic monohydric alcohol, methanol, ethanol, isopropyl alcohol, n −
When an aliphatic monohydric alcohol such as propanol is used, it is difficult to control the polycondensation reaction because it easily binds or solvates with the silanol group to inhibit polycondensation, and it flows out of the system in the subsequent polycondensation process. Therefore, it is preferable to use an organic solvent other than the aliphatic monohydric alcohol. In the condensation polymerization step, it is preferable that the aliphatic monohydric alcohol produced by the hydrolysis of dialkoxysilane (1) and phenyl or methyltrialkoxysilane (2) is allowed to flow out of the system.

When a solvent consisting of water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol is used, the proportion of water is 0.5 to 0.5 with respect to the alkoxy group of the alkoxysilane contained in the system. The amount of 3.0 equivalents is preferable from the viewpoint that the reaction rate is high and the homogeneity of the system is maintained. If the proportion of water is higher than the above range, layers tend to separate in the system.

When the silicone oligomer solution is produced from the above-mentioned dialkoxysilane (1) to water or a solvent (4) consisting of water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol, the proportion of each component used is as follows: Phenyl or methyl trialkoxysilane (2) 150 to 50 per 100 parts of dialkoxysilane (1) (parts by weight, the same applies hereinafter)
00 parts, and more preferably 165 to 1650 parts are preferable from the viewpoint of improving the mechanical strength and heat resistance of the cured product. Based on 100 parts by total of these, no metal is contained and at least 1 atom of chlorine atom and phosphorus atom is contained. Species-containing inorganic acid or PKa
Organic acid having a value of 0.8 to 6 (3) 0.1 to 10.0
Parts, more preferably 0.2 to 2.0 parts are preferable from the viewpoint of easy control of the condensation polymerization reaction. Then, as described above (1) to (2)
0.5-3. With respect to the amount of the alkoxy groups contained in the component.
The reaction rate is faster when water is added so that the amount becomes 0 equivalent.
It is preferable from the viewpoint of maintaining the uniformity of the system. It is not always necessary to add a water-soluble organic solvent excluding the aliphatic monohydric alcohol, but if it is necessary to slow the polycondensation reaction, obtain a high molecular weight product, or lower the viscosity by dilution, add it. Is preferred. For example, the intrinsic viscosity is 3 cm ³ / g (25
When the oligomer of (℃) is obtained, the initial concentration of the component is 25 ~
It is preferable to dilute it to 60%.

The silicone oligomer (A) used in the present invention has an intrinsic viscosity of 0.1 to 10 cm at 25 ° C. obtained by dehydration condensation of a mixture of the above components (1) to (4) under heating. ³ / g, and further 0.5 to 7 cm ³ /
g, toluene / isopropanol = 1/1 as solid content of 50% (% by weight, the same applies hereinafter) using an E type rotational viscometer
The viscosity obtained by measuring (by weight) as a solvent at 25 ° C. is 5 to 5000 mPa · s, and further 10
It is preferably 2000 mPa · s.

When the silicone oligomer is used as a solution, it is preferably a solution containing the silicone oligomer in a concentration of 10% or more, further 30% or more. The solvent must be compatible with the added aliphatic monohydric alcohol and should dissolve the obtained oligomer.

The conditions for dehydration condensation under heating will be described in the method for producing a silicone varnish described later.

The intrinsic viscosity was measured by using a Uberode viscometer in a constant temperature layer at 25 ° C., toluene / isopropanol = 1/1.
It is a value measured using a dilute solution (based on weight). When the intrinsic viscosity is within the range, it becomes solid (tack free) when dried, and can be melted or softened by heating to be molded. However, if it deviates from the above range, it remains liquid even when dried, or melts even at high temperature, does not soften, and cannot be molded.

The silicone varnish of the present invention contains the above-mentioned silicone oligomer solution (A), an aliphatic monohydric alcohol or a mixed solvent (B) containing the same, and a condensation catalyst (C) containing a metal atom.

The aliphatic monohydric alcohol or the mixed solvent (B) containing the same is added to the obtained silicone oligomer solution (A) to improve the storage stability of the silicone varnish containing the silicone oligomer solution (A). It is an ingredient for doing.

The reason why the storage stability of the silicone varnish containing the silicone oligomer solution (A) is improved by adding the aliphatic monohydric alcohol or the mixed solvent (B) containing the same is clearly understood. But not
It is speculated that this may be because the silanol groups remaining in the silicone oligomer after polycondensation are capped or solvated.

Specific examples of the aliphatic monohydric alcohol or the aliphatic monohydric alcohol in the mixed solvent (B) containing the same include methanol, ethanol, isopropanol,
Examples include normal propanol, isobutanol, tertiary butanol, and normal butanol. These may be used alone or in combination of two or more.
Of these, methanol, ethanol, isopropanol, and normal propanol are preferable from the viewpoint of storage stability and solubility of the condensation polymerization catalyst.

The condensation catalyst (C) containing a metal atom contains the silicone varnish of the present invention, and when the solvent is volatilized and heated, the formation of the network of the silicone oligomer immediately progresses, gels, and is tough. It is a component that allows a cured product to be obtained in a short time.

Specific examples of the condensation catalyst (C) containing a metal atom include various salts of tin, lead, zinc, cobalt, manganese, iron such as naphthenic acid, octenoic acid, heptanoic acid, nonanoic acid, and the like. 4 alkoxy groups (specifically methoxy, ethoxy, isopropoxy, normal propoxy,
Normal butoxy, isobutoxy and the like) or monotitanium compounds including the same alkoxy having 1 to 4 carbon atoms and acetoxy as mentioned above and the like. Specific examples thereof include zinc naphthenate, tin naphthenate, iron naphthenate, cobalt naphthenate, lead naphthenate, manganese naphthenate, zinc octenoate, cobalt octenoate,
Lead octenoate, tin octenoate, zinc heptanoate, cobalt heptanoate, lead heptanoate, zinc nonanoate, lead nonanoate, tin nonanoate, cobalt nonanoate, tetramethoxytitanium, tetraethoxytitanium, tetraisopropoxytitanium, tetra Examples thereof include normal propoxy titanium, tetranormal butoxy titanium, tetraisobutoxy titanium, dinormal propoxydiacetoxy titanium, diisopropoxydiacetoxy titanium, dieoxydiacetoxy titanium, and dimethoxydiacetoxy titanium.
These may be used alone or in combination of two or more. Among these, zinc naphthenate, tin naphthenate, iron naphthenate, cobalt naphthenate, lead naphthenate, manganese naphthenate, zinc octenoate, cobalt octenoate, lead octenoate, tin octenoate, tetramethoxytitanium, tetra Ethoxytitanium, tetraisopropoxytitanium, tetranormalpropoxytitanium, and tetranormalbutoxytitanium are preferred because of their large catalytic effect on silanol polycondensation.

The content of the silicone oligomer (A), the aliphatic monohydric alcohol or the mixed solvent (B) containing the same and the condensation catalyst (C) containing a metal atom in the silicone varnish of the present invention is as follows. ) 20 to 500 parts, more preferably 25 to 300 parts, of an aliphatic monohydric alcohol or a solvent (B) containing the same per 100 parts (solid content) is preferable from the viewpoint of storage stability and drying rate of the oligomer solution, and It is preferable to use a mixed solvent because an oligomer having a high intrinsic viscosity becomes difficult to dissolve in an aliphatic monohydric alcohol. Further, 0.04 to 1.6 parts of the condensation catalyst (C) containing a metal atom, and further 0.08 to 0.
8 parts is preferable from the viewpoint of reaction efficiency and heat resistance of the cured product.

Next, a method for producing the silicone varnish of the present invention will be described.

The method for producing the silicone oligomer solution (A) is not particularly limited, but heat is generated when the dialkoxysilane (1) and the phenyl or methyltrialkoxysilane (2) are hydrolyzed, so that the liquid temperature is 40. It is preferable to control the addition rate according to the production scale and to introduce a cooling device so that the temperature does not rise above 0 ° C.

The alkoxysilanes may be collectively hydrolyzed and used, or may be preliminarily hydrolyzed and used in separate containers, but it is preferable to preliminarily hydrolyze and use them in separate containers.
It is preferable in that the heterogeneity of the system and the heterogeneous condensation due to the difference in the hydrolysis reaction rate are prevented, and the end point of the hydrolysis (the point at which the heat generation ends and the system becomes uniform) can be clearly understood. When they are put together, the one with strong hydrolyzability will be decomposed first, and the one with strong hydrolyzability will tend to be condensed first due to the heat of reaction during hydrolysis of the one with weak hydrolyzability. .

Hydrolysis of the alkoxysilane is carried out by using an inorganic acid containing no water, no metal and containing at least one of chlorine atom and phosphoric acid atom, or an organic acid having a PKa value of 0.8 to 6. In the meantime, it is preferable to add an alkoxysilane in a container mixed with a water-soluble organic solvent excluding the aliphatic monohydric alcohol according to the amount of heat generation, from the viewpoint of preventing gelation and cyclization due to temperature rise (specifically, Liquid temperature is 20
Try to maintain ~ 40 ° C).

When the water-soluble organic solvent excluding the aliphatic monohydric alcohol is used, the water-soluble organic solvent excluding the aliphatic monohydric alcohol may be added in the entire amount from the beginning, or the addition of the alkoxysilane. However, it is preferable to add the entire amount from the beginning because the initial temperature control is easier and the work is easier.

The hydrolysis reaction is started when the liquid temperature rises after the alkoxysilane is added. Specifically, it is preferable to maintain the liquid temperature at 20 to 40 ° C. The alcohol produced by the hydrolysis is removed from the system during the condensation polymerization.

When the dialkoxysilane (1) and the phenyl or methyltrialkoxysilane (2) are hydrolyzed separately, the two hydrolyzed solutions are mixed at a predetermined ratio and then again. When the hydrolysis of the dialkoxysilane (1) and the phenyl or methyltrialkoxysilane (2) is carried out all at once, it may be directly transferred to the next condensation polymerization step.

In the polycondensation step, it is preferable that the alcohol produced by the decomposition of the alkoxy group is allowed to flow out of the system. Therefore, a reaction vessel having a liquid reservoir attached to the end of the cooling pipe is attached to allow the alcohol to flow out of the system. .

The polycondensation temperature is 60 to 180 ° C., and further 9
0-150 degreeC is preferable. When the polycondensation temperature is lower than 60 ° C., it takes a long time to carry out the polycondensation, which is not practical. When the polycondensation temperature exceeds 180 ° C., gelation tends to occur, and control of the molecular weight becomes difficult.

Since the polycondensation reaction temperature is affected by the boiling points of the volatile components contained in the system, when, for example, methoxysilane is used, the methanol produced is volatilized and the liquid temperature in the reaction vessel is about 80.degree. Once stabilized, the temperature of the methanol starts to rise outside the system, the temperature starts to rise again, and the temperature rises to the target temperature (for example, about 150 ° C.). After the temperature has risen to the target temperature, it is preferable to control the temperature precisely (for example, to a temperature not exceeding 155 ° C.). The temperature rising rate depends on the structure of the reaction vessel and the scale.

When methyl cellosolve is used as the reaction solvent, the produced methanol is volatilized so that the temperature stabilizes once at around 80 ° C., and the temperature rises gradually as the methanol flows out of the system to 150 ° C. Get nervous.

The polycondensation time varies depending on the degree of polymerization of the desired silicone oligomer, the reaction amount, the temperature, the reaction temperature and the like.

When the desired degree of polymerization (or viscosity) is reached, the reaction may be stopped and cooled. If you want to obtain a polymer with a high degree of polymerization, the viscosity of the product is high and the workability is not good, so add a solvent with low solubility in water, such as toluene, during the reaction and add it to the Dean Stark (DEAN Stark) reactor. By adding a (STARK) separating tube and refluxing only the toluene layer into the reaction vessel, it is possible to prevent an increase in the solid content concentration of the solution in the reaction vessel.

After cooling, the aliphatic monohydric alcohol or the mixed solvent (B) containing it is added.

The amount of the aliphatic monohydric alcohol or the mixed solvent (B) containing the same to be added is preferably at least 1/4 times the equivalent of the charged alkoxy groups from the viewpoint of the storage stability of the solution. It is preferably 1/3 times equivalent or more.

There is no problem if the solvent to be added is only an alcohol solvent, but it is preferable that the obtained polycondensation product can be dissolved. Therefore, it may be used in combination with another solvent. .

Specific examples of the other solvent include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, methylene chloride, chloroform, cyclohexanone, carbitol, methyl cellosolve, ethyl cellosolve, cellosolve acetate, dimethylformamide, nitrobenzene, etc. Can be given. It is not always necessary to add these solvents, and the timing of addition may be during the condensation reaction or after the completion of the reaction. However, when it is added during the reaction, it is necessary to confirm the solubility in the oligomer in the system.

The condensation catalyst (B) containing a metal atom, which is a silanol polycondensation catalyst, is added to the silicone oligomer solution containing the obtained solvent. Generally, when the condensation catalyst (B) containing a metal atom is added, the storage stability of the silicone oligomer solution is significantly impaired, but since the silicone varnish of the present invention contains an alcohol solvent, polycondensation of silanol groups is suppressed. Therefore, the silicone varnish can be kept stable.

The thus obtained silicone varnish is a stable one which does not show an increase in viscosity even if it is sealed and stored at 45 ° C. for half a year.

One embodiment of the method for producing the silicone varnish of the present invention as described above is as follows.

Methyl cellosolve (hereinafter sometimes referred to as MCS) 0-600 parts, phosphoric acid 10% aqueous solution 1-2
0 part and 80 to 490 parts of water are placed in a beaker, and phenyltrimethoxysilane (hereinafter referred to as PTrM
Also called OS) 300 parts little by little, 30
Stir for minutes to obtain solution (a).

Separately, 0 to 300 parts of MCS, 1 to 10 parts of 10% phosphoric acid aqueous solution, and 6 to 165 parts of water were placed in a beaker and stirred, and dimethyldimethoxysilane (hereinafter sometimes referred to as MCS). 18.2-182 parts were added little by little, and the mixture was stirred as it was for 20 minutes to obtain solution (b).
Get

First, in a reaction vessel equipped with a cooling tube equipped with a liquid reservoir (for example, an Erlenmeyer flask, a beaker, a bucket, etc.), a thermometer and a stirring blade,
The above-mentioned solutions (a) and (b) are charged and the reaction vessel is heated. Since the temperature of the solution in the reaction container gradually rises when the liquid containing methanol as a main component starts to collect in the liquid reservoir, the temperature of the solution in the reaction container is adjusted to 120 to 150 ° C. as a guide.

The temperature of the solution in the reaction vessel gradually rises,
When the temperature exceeds 80 ° C., the product in the reaction vessel is sampled and the viscosity is measured by an E-type rotational viscometer. The sampling interval is preferably about 30 to 60 minutes. In addition, this measurement is toluene / isopropanol = 1.
It is performed after diluting to a solid content of 40% with a 1/1 (weight basis) solution. Here, when the rotational viscosity reaches 120 mPa · s, the reaction vessel is allowed to cool, and the temperature of the contents is lowered to a temperature below the boiling point of the aliphatic monohydric alcohol used.

However, the final target viscosity (rotational viscosity) is 12
If it is 0 mPa · s or less, as soon as the target viscosity is reached, the temperature of the reaction vessel is lowered to a temperature below the boiling point of the aliphatic monohydric alcohol used, and then 20 parts or more of the aliphatic monohydric alcohol is added to stop the reaction. Let

On the other hand, the final target viscosity (rotational viscosity) is 120.
If it exceeds mPa · s, after lowering the temperature of the contents to 100 ° C, add 20 to 150 parts of a water-insoluble solvent having a boiling point of 100 ° C or higher, such as toluene or xylene, from the reaction vessel. Remove the cooling tube and replace it with the Dean-Stark separator. Then, heating is performed again to reflux the system. The water-insoluble solvent and water are evaporated, but only the water-insoluble solvent is refluxed into the system by the Dean-Stark tube, and the water is removed to the outside of the system. When the viscosity (rotational viscosity) of the polycondensation product in the reaction vessel reaches the target point, the reaction vessel is allowed to cool and the temperature of the contents is lowered to a temperature below the boiling point of the aliphatic monohydric alcohol used.

Further information on the product can be obtained by NMR
(Si ₂₉ ) can be used. For example, for the product synthesized by using a phenylmethyl silane and dimethyl dimethoxy silane, in the _{NMR, (CH 3) 2 (} OH) Si-O-Si is -5 to -10
in _{ppm (D 1), (CH} 3) is ₂ Si (OSi) ₂ -15
To _{~-25ppm (D 2),} Ph-Si (OSi) (O
H) ₂ is −55 to −65 ppm (T ₁ ), and PhSi (O
Si) ₂ (OH) is -65 to 75 ppm (T ₂ ), Ph
Si (OSi) ₃ corresponds to -75~-85ppm (T _3). From the NMR spectrum, the product (D ₁ + T ₁ +
The area ratio of (T ₂ ) to (D ₂ + T ₃ ) is 70:30 to 10 :.
90, and it was confirmed that the silanol group remained and the polycondensation due to the siloxane bond. However, since this area ratio is not quantitative, it does not directly quantitatively represent the amount of residual silanol groups, and it is sufficient to confirm the product identification by IR.

In this way, a reaction vessel containing the content adjusted to the desired viscosity was added to 100 parts of the content.
Add 20 parts or more of an aliphatic monohydric alcohol such as isopropyl alcohol, ethanol or normal butanol, and stir sufficiently until the system becomes uniform. Further, a polymerization catalyst containing a metal atom such as lead naphthenate, cobalt naphthenate, lead octenoate or alkoxytitanium 0.1 to 2
A suitable silicone varnish can be obtained by dissolving 10 parts by weight (100 parts by weight of the content) in an aliphatic alcohol solvent having a weight of 10 times, and then adding the resulting solution and stirring it sufficiently.

The molecular weight of the silicone varnish thus obtained can be relatively evaluated by an intrinsic viscometer. The intrinsic viscosity (25 ° C) of the obtained silicone varnish is 0.1-1.
The decrease of 0 cm ³ / g or silanol groups due to polycondensation can be judged by the decrease of the peak area near 900 cm ^{−1 in the} infrared spectrum. However, when it is cured, the peak of the siloxane bond is widened due to the increase of the siloxane bond due to the condensation of the silanol unit, and the absorption of silanol is overwhelmed.

The heat resistance after drying and curing the obtained varnish can be evaluated by TGA (thermal content analysis). For example, the temperature at which 5% weight loss occurs in the atmosphere is 30
0-500 ° C.

The silicone varnish of the present invention has a wide range of uses. For example, a prepreg, a laminated board for a printed board manufactured from the prepreg, a printed board, various other composite materials, a composite molded article, and a build-up for an electronic circuit module. Used for manufacturing multi-layer substrates.

For example, when the silicone varnish of the present invention is used for the production of a silicone varnish-impregnated prepreg, the reinforcing cloth, the nonwoven fabric or the filament is impregnated with the silicone varnish and dried to a tack-free state to impregnate the silicone varnish. Prepregs can be manufactured.

Specific examples of the reinforcing cloth are woven fabrics made of glass fiber, carbon fiber, aramid fiber and the like (for example, glass cloth, carbon cloth, aramid cloth, etc.) and have a weight of 150 to 250 g /
One of them is about m ² .

Specific examples of the non-woven fabric include non-woven fabrics such as alumina sheets, SiCF sheets and carbon fiber sheets produced from alumina, silicone carbide, aramid, PAN-based carbon fiber, rayon-based carbon fiber and the like. .

Furthermore, specific examples of the filament include glass fiber, aramid fiber, and SiCF manufactured from glass, aramid, silicone carbide and the like.

The silicone varnish impregnated into the reinforcing cloth, nonwoven cloth or filament has a viscosity (25 ° C.).
30 to 200 cp, intrinsic viscosity (25 ° C) 1 to 10 c
A varnish having a m ³ / g level and a solid content rate of 30 to 80% is preferable, but the optimum range of the intrinsic viscosity varies depending on the application of the prepreg. For example, when the obtained silicone varnish-impregnated prepreg is used as a prepreg for producing a laminated plate by laminating a plurality of sheets, specifically, 2 to 100 sheets, preferably 10 to 60 sheets, a prepreg is formed using a press. By the way, it is preferable that the intrinsic viscosity (25 ° C.) is ^{3 to} 6 cm ³ / g. In addition, for example, when the obtained silicone-impregnated prepreg is covered with a base material or wound in a ribbon shape to be heat-cured or laminated without using a press, a lower melt viscosity is preferable, Those having an intrinsic viscosity (25 ° C.) of 1 to 4 cm ³ / g are preferable.

The ratio of the silicone varnish (solid content) to the reinforcing cloth, non-woven fabric or filament in the prepreg impregnated with the silicone varnish is a treatment ratio (weight of prepreg after drying / pre-impregnation after impregnation) from the viewpoint of mechanical strength of the molded product. The weight of the reinforcing cloth, the non-woven fabric or the filament is 1.2 to 3.0, and further 1.3 to 2.
5 is preferable, in the case of non-woven fabric, 1.3 to 5.0, more preferably 1.4 to 3.0, and in the case of filament, 1.5 to 7.0, and further 1.7 to 4.0. preferable.

The thickness of the prepreg impregnated with silicone varnish is 0.05 to 0.5 when a reinforcing cloth is used.
mm, further 0.1 to 0.3 mm, when using a non-woven fabric, 0.1 to 15 mm, further 0.3 to 5 mm, when using a filament, 0.2 to 8 mm, further 0. It is preferably 3 to 5 mm from the viewpoint of the drying speed of the prepreg and the bending strength of the molded product.

The silicone varnish-impregnated prepreg as described above is impregnated with a silicone varnish into a reinforcing cloth according to a conventional method, and then dried by, for example, heating at 120 ° C. for about 10 minutes to obtain a tack-free state. Manufactured by The produced prepreg is a storage-stable product produced by using an inorganic acid whose silicone varnish does not contain a metal and contains at least one kind of chlorine atom and phosphorus atom, or an organic acid having a PKa value of 0.8 to 6. Since it has good properties, it has good storage stability even after the solvent is removed. The storage stability of prepreg is
Although three months at normal 30 ° C. is prospect, those of the present invention 4
It has a storage stability at 5 ° C for 6 months or more. In the case of a prepreg made from conventional silicone varnish,
It can be stored at 30 ° C for only one month.

Also, in the prepreg dried to be tack-free, the aliphatic monohydric alcohol effective for maintaining the storage stability of the prepreg remains, and these inhibit the silanol condensation. The storage stability of is also improved.

The composite material obtained by stacking a plurality of silicone-impregnated prepregs (usually 2 to 50) and thermosetting them has a thickness of about 0.3 to 8 mm, has excellent mechanical strength, and is made of glass. -It has characteristics that the dielectric constant is lower and the dielectric loss is smaller than that of the epoxy laminate. Therefore, by providing a metal layer of copper, aluminum or the like having a thickness of about 15 to 80 μm on both surfaces or one surface of the composite material, the composite material can be used as a laminated board for a printed circuit board.

A printed circuit board can be manufactured by forming a circuit on one side or both sides of the above-mentioned laminated board for printed circuit boards, and further, two or more, preferably 2 to 15 printed circuit boards thus manufactured. By stacking, sandwiching the silicone varnish-impregnated prepreg between the printed circuit board and the printed circuit board, and performing hot press molding,
A printed circuit board having a multilayer structure can be manufactured.

When the composite material is manufactured by covering or winding the silicone-impregnated prepreg on a base material and then thermosetting, a base material such as a copper pipe, a steel pipe, a stainless pipe, or an aluminum pipe is used as a base material. Winding a prepreg around, heat-curing pipe obtained by heat curing, glass-
Heat resistant heat resistant laminated plate coated with prepreg on both or one side of epoxy laminated plate, side and back side of mold are covered with prepreg, and heat-cured molding die with low heat dissipation and high heat efficiency. In particular, for heat insulation and insulation of heaters and heat medium pipes, it can be easily adhered to the surface of curved surfaces, rectangular surfaces, or long objects that are difficult to pressurize It can be preferably used.

In the silicone varnish of the present invention, instead of producing the prepreg as described above, a mixture of the silicone varnish and inorganic powder, particles or whiskers is produced and heated to remove the solvent to obtain a film-like substance. Alternatively, it may be used as a solid.

In this case, as the silicone varnish,
Its viscosity is 1000 to 50,000 cP, and its intrinsic viscosity is 2
10 cm ³ / g and a solid content of 30 to 80% are good in defoaming property, easy in the drying process, capable of being pulverized and formed into a film (because of not sticking), powder or It is preferable in terms of good moldability from a film.

Examples of the inorganic powder, particles or whiskers mixed with the silicone varnish include carbon, alumina, silica, boron nitride, silicon nitride, aramid, titanium oxide and PZT. In this case, it is preferable that the particles have a diameter of 5 to 100 μm, because it is easy to effectively impart the characteristics of the particles (for example, high thermal conductivity, high dielectric constant, etc.) to the resin molded product. In this case, the average shape is preferably 0.5 to 15 μm in fiber diameter and 5 to 500 μm in length.

The mixing ratio of the inorganic powder, particles or whiskers to the silicone varnish is such that the inorganic powder, particles or whiskers are about 50 to 90% by volume of the molded product, which is a characteristic of the particles (eg, , High thermal conductivity,
(High dielectric constant, etc.) is preferable because it can be effectively imparted to the resin molded product and the strength as a molded product can be sufficiently maintained.

The mixture is preferably dried at a low temperature of about room temperature to 80 ° C. so that the condensation reaction does not proceed, and the pressure can be reduced at this temperature to efficiently dry the mixture.

When the silicone varnish is formed into a film, it can be obtained by casting the silicone varnish on a Teflon-coated plate or flat plate and drying. At this time, the film thickness can be adjusted to about 50 μm to 5 mm.

When the silicone varnish is made into powder, it can be obtained by crushing the film-like material. In this case, it is difficult to control the particle size, so
After crushing, the particles may be separated using a sieve.
The particle size is not particularly limited, but it is preferably 3 mm or less from the viewpoint of ease of molding into a solid.

The heat resistance and mechanical strength of the film-like material or solid thus obtained are remarkably improved by heat molding.

For heat molding, it is preferable to use a vacuum press or a vacuum mold. The film is suitable for forming a slab by stacking 2 to 30 sheets and pressing it, and a slab having a maximum thickness of 10 mm can be formed at one time.

When the powder is used, it is suitable for molding a solid having a complicated shape. For example, a molded body can be obtained by a method in which the powder is packed in a mold and the powder is melt-cured by hot pressing. When packing the powder into the mold, use a vibrator etc.
It can be suitably packed.

The heating conditions are preferably 170 to 300 ° C. and 2 to 7 hours.

As an embodiment of the composite molded article produced in this manner, for example, alumina particles alone or a high thermal conductive resin material containing alumina particles and boron nitride particles, high dielectric constant particles such as TiO ₂ particles are used. Examples of such materials include high dielectric constant capacitor materials.

As the particles used for the high thermal conductive resin material, in addition to the above alumina particles and boron nitride particles, for example, aluminum nitride particles, silicone carbide particles, silicon nitride particles, magnesium oxide particles, beryllium oxide particles. , Crystalline silica particles and the like are preferable, and in consideration of dispersibility, low hygroscopicity and insulating property, boron nitride particles, alumina particles and aluminum nitride particles are preferable.

As the particles used for the high dielectric constant capacitor material, in addition to the above TiO ₂ particles, BeTiO ₃ , M
gTiO ₃ , CaTiO ₃ , SrTiO ₃ , BaTiO ₃ ,
PbTiO ₃ , ZrTiO ₃ , BiTiO ₅ , La ₂ TiO
₅ , CeTiO ₄ , ZrTiO ₄ , BaSnO ₃ , CaS
nO ₃ , SrSnO ₃ , MgSnO ₃ , Bi ₂ (Sn
O ₃ ) ₃ , PbSnO ₃ , CoSnO ₃ , NiSnO ₃ , B
aZrO ₃ , CaZrO ₃ , SrZrO ₃ , MgZrO ₃ ,
(Bi ₂ O ₃ ) ₂ · (ZrO ₂ ) ₃ , MgNbO ₃ , CaNb
O ₃ , SrNbO ₃ , BaNbO ₃ , PbNbO ₃ , LiN
bO ₃ , FeNb ₂ O ₆ , LiTaO ₃ , BaTaO ₃ , S
rTaO ₃ , CaTaO ₃ , MgTaO ₆ , Bi ₃ TiNb
O ₉ , PbZrO ₃ -PbTiO ₃ , PbBi ₂ NbO ₉ ,
Examples of the particles include Bi ₄ Ti ₃ O _{12 and the} like. Particularly, in view of thermal stability of dielectric constant, TiO ₂ particles, MgTiO ₃ particles,
CaTiO ₃ particles, SrTiO ₃ particles, BaTiO ₃ particles and PbZrO ₃ —PbTiO ₃ particles are preferred.

A heat dissipation printed circuit board can be manufactured by using the high thermal conductive resin material, adhering it to a metal plate such as an aluminum substrate, and further adhering a copper foil thereto. This heat dissipation printed board is suitable for a component mounting board such as a power module that requires heat dissipation.

Further, it is possible to manufacture a capacitor component having a sandwich structure by using the high dielectric constant capacitor material and sandwiching it with electrodes. In addition, the high dielectric constant capacitor material is formed into a film and directly attached to a substrate, so that it can be suitably used as a coupling capacitor.

The composite material produced by using the silicone varnish according to the present invention is usually porous and therefore has a characteristic that the dielectric constant and the dielectric loss are extremely small.

For example, phenyltrimethoxysilane 1
0 parts, 4.1 parts of dimethyldimethoxysilane, 5 parts of methyl cellosolve, 0.2 parts of 10% aqueous phosphoric acid solution were charged and reacted by heating to obtain a polycondensation product having an intrinsic viscosity of 3.0 cm ³ / g. Dilute with a mixed solution of toluene / isopropanol = 1/1 (weight basis) so that the content becomes 55%,
A silicone varnish obtained by adding 0.7 part of tetraisopropoxytitanium was used as D- with a thickness of 8000 yds / Ld.
The glass fiber has a density of 43.8 vertical / 25 mm, horizontal 32.6 / 25 mm, thickness 0.192 mm, weight 19
A plain weave cloth of 0.8 g / m ² was impregnated with silicone varnish and dried at 120 ° C. for 10 minutes to obtain a treatment ratio of 1.
30 sheets of prepreg of No. 7 are piled up,
It was pressed at cm ² for 1 hour, further heat-treated at 200 ° C. for 2 hours and then at 250 ° C. for 3 hours to obtain a laminated plate, and the relative permittivity and dielectric loss tangent of this laminated plate were measured. = 3.2, dielectric loss tangent = 8 × 10 ⁻⁴ (1M
Hz).

Since the silicone varnish of the present invention contains a small amount of acid and metal ions, it may be unsuitable as an interlayer insulating film for semiconductors. For example, it can be used as an interlayer insulating film of an electronic circuit module such as a multichip module. Is sufficiently compatible, and is not inferior to the conventionally used epoxy-based interlayer insulating film in electrolytic corrosion resistance (evaluable under conditions such as 50 ° C. and 85% RH).

[0099]

EXAMPLES The present invention will be described below based on specific examples, but the present invention is not limited to these examples.

[Example 1] Water-soluble organic solvent except aliphatic monohydric alcohol (hereinafter, also referred to as water-soluble organic solvent)
(4) 10.0 g of methyl cellosolve, an inorganic acid containing no metal and containing at least one of a chlorine atom and a phosphorus atom, or an organic acid having a PKa value of 0.8 to 6 (hereinafter referred to as metal-free hydrolyzate). As a decomposition acid catalyst (3), 1.0 g of a 10% aqueous solution of phosphoric acid and 26.6 g of water were placed in a beaker, and dimethyldimethoxysilane (hereinafter, DMD) was used as a dialkoxysilane (1) while stirring.
88.8 g (0.74 mol) of MOS) was added little by little, and the mixture was stirred for 20 minutes as it was. The obtained mixed solution is referred to as solution 1-a. Since the IR spectrum of the solution 1-a showed Si—OH absorption which was not found in dimethyldimethoxysilane near 900 cm ⁻¹ , the solution 1-a was identified as a solution containing a hydrolyzate of dimethyldimethoxysilane.

Separately, 50.0 g of methyl cellosolve as the water-soluble organic solvent (4), 4.0 g of a 10% aqueous solution of phosphoric acid and 130.6 g of water as the metal-free hydrolytic acid catalyst (3) were placed in a beaker. While stirring, 480.0 g (2.42 mol) of phenyltrimethoxysilane (hereinafter also referred to as PTrMOS) as phenyl or methyltrialkoxysilane (2) was added little by little,
The mixture was stirred for 30 minutes as it was. The obtained solution is solution 1-b
That. The IR spectrum of the solution 1-b shows that the absorption of Si—OH which is not found in phenyltrimethoxysilane is 900 cm ^−1.
Since it was shown in the vicinity, Solution 1-b was identified as a solution containing a hydrolyzate of phenyltrimethoxysilane.

Solution 1-a and solution 1- were placed in a 1-liter separable flask (hereinafter referred to as a reaction vessel) equipped with a liquid reservoir (Erlenmeyer flask) at the end of the Liebig cooling tube and equipped with a thermometer and stirring blades. b was added and mixed, the reaction vessel was immersed in an oil bath, and the temperature of the oil bath was raised to 170 ° C. over 140 minutes. As a result, a liquid containing methanol as a main component was accumulated in the liquid reservoir.

Since the temperature in the reaction vessel gradually rises as the liquid containing methanol as the main component evaporates from the mixed solution, after raising the oil bath to 170 ° C. as described above, 150 this oil bath
Adjusted to ° C.

After 80 minutes from the start of the reaction, the power of the oil bath was turned off, and the reaction vessel was kept in the oil bath until the temperature of the contents reached 100 ° C. The temperature of the contents is 10
When the temperature reached 0 ° C, toluene 63.
After adding 7 g, the Liebig tube was removed and replaced with a Dean Stark tube. 1 hour of the silicone oligomer solution (polycondensation polymer) in the reaction vessel
3.2 g of isopropyl alcohol (hereinafter, also referred to as IPA) (3.2 g) was added, and the viscosity was measured with an EL viscometer to stop the reaction at 350 to 450 mPa · s. The intrinsic viscosity at this time corresponds to 4 to 5 cm ³ / g. Since the Si-OH absorption area of the IR spectrum was smaller than that before heating, it was confirmed to be a product of the condensation reaction. When the intrinsic viscosity determined by the flow time of the 0.1-5% solution in a high-temperature tank at 25 ° C using a Uberode type viscometer was 4-5 cm ³ / g, the reaction vessel was pulled up from the oil bath, After allowing to cool to 60 ° C. or lower, 63.7 g of IPA was added and well stirred until the content in the reaction vessel became uniform. Furthermore, 5.6 g of zinc naphthenate 8% mineral spirit solution was added and well stirred to obtain a silicone varnish. The obtained silicone varnish is called silicone varnish 1.

To 100 parts of the silicone varnish 1 was added I
The viscosity of a solution to which 25 g of a mixed solvent of PA / toluene = 1: 1 was added was 55 mPa · s. 45 of this solution
The viscosity after storage at 6 ° C for 6 months was 58 mPa · s.

120 mm × 3 of the above silicone varnish
E-glass fiber having a diameter of 9 μm cut into 00 mm was plain-woven, and 55% was impregnated in a glass cloth having a surface subjected to aminosilane treatment, followed by drying in a hot air oven at 120 ° C. for 10 minutes to prepare a prepreg. The surface of the obtained prepreg had no tack and could be stored in layers. The obtained prepreg is called silicone prepreg 1-a.

100 mm of silicone prepreg 1-a
After cutting into 100 mm and stacking 30 sheets, press using a press machine at a pressure of 10 Kgf / cm ² and a temperature of 170 ° C. for 1 hour, remove from the press machine, and use a hot air stove to
The laminate was cured by treatment at 00 ° C. for 2 hours and then at 250 ° C. for 3 hours to obtain a laminated plate having a thickness of 5 mm. The obtained laminated plate is referred to as a silicone laminated plate 1-a.

The silicone laminated plate 1-a is compliant with JIS-691.
When the bending strength test was conducted according to the method of 1,
The breaking strength was 20 Kgf / mm ² . This breaking strength is larger than, for example, a practical value of 10 kgf / mm ² or more when it is used for a printed circuit board. Further, the laminated plate was kept at 300 ° C. for 90 days by using a hot air oven, and the bending strength (bending strength after thermal deterioration) was measured by the above method. The breaking strength was 17 Kgf / mm ² .
For example, in the case of a glass-epoxy laminate, this breaking strength deteriorates to 0.5 Kgf / mm ² or less, making it impractical.

Next, silicone varnish 1 and DCG80
No. D glass fiber was plain-woven, and a prepreg using a glass cloth having a surface subjected to aminosilane treatment was prepared.
The obtained prepreg is called silicone prepreg 1-b.

Using the silicone prepreg 1-b, a laminated plate having a thickness of 5 mm was prepared in the same manner as in the case of the silicone prepreg 1-a. The obtained laminated plate is referred to as a silicone laminated plate 1-b.

Silicone prepreg 1-b was laminated on both sides of the silicone laminate 1-b, and the both sides were sandwiched with copper foil having a thickness of 100 μm, and the temperature was 170 ° C. and the pressure was 10 Kgf / cm using a pressing machine. Press at ² for 1 hour, remove from the press and use a hot air stove for 2
The silicone laminate provided with the copper foil layer was obtained by curing by treating at 00 ° C. for 2 hours and then at 250 ° C. for 3 hours.

By etching the copper foil layer of the silicone laminate provided with the copper foil layer, the dielectric characteristics are changed to YOKOGAWA H.
EWLETT PACKERD 4274A MULT
Using I-FREQUENCY LCR METER,
When measured by the capacitance method, the relative dielectric constant was 3.3 and the dielectric loss tangent was 0.001 under the condition that the measurement frequency was 1 MHz.

Example 2 The dialkoxysilane (1) shown in Table 1, the water-soluble organic solvent (4), the metal-free hydrolyzed acid catalyst (3) and water were used in the amounts shown in Table 1. Others were the same as in Example 1 to obtain a mixed solution, and the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 2-a.

DMDEOS in Table 1 represents dimethyldiethoxysilane.

Separately, the phenyl or methyl trialkoxysilane (2), the water-soluble organic solvent (4), the metal-free hydrolyzed acid catalyst (3) and the water listed in Table 2 are listed in Table 2. A mixed solution was obtained in the same manner as in Example 1 except that the amount was used, and the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 2-b.

PTrEOS in Table 2 represents phenyltriethoxysilane.

Next, the solution 2-a and the solution 2-b were used in place of the solution 1-a and the solution 1-b, and the temperature of the oil bath was raised to 95 ° C. over 110 minutes. In the same manner as in Example 1 to obtain a silicone oligomer solution, the silicone oligomer solution having an EL type rotational viscometer viscosity of 20.
When it reached 0 mPa · s and the intrinsic viscosity reached 3 cm ³ / g, it was allowed to cool to below 60 ° C. After that, the aliphatic monohydric alcohol shown in Table 3 or a mixed solvent containing the same (hereinafter, also referred to as an aliphatic monohydric alcohol solvent) (B)
And the condensation catalyst (C) containing a metal atom was added in an amount shown in Table 3 and stirred well to obtain a silicone varnish. Identification of the condensation reaction product was performed by IR spectrum. The obtained silicone varnish is called silicone varnish 2.

The viscosity change of the silicone varnish 2 after storage at 45 ° C. for 6 months was measured in the same manner as in Example 1. Table 4 shows the results.

A laminate for measuring bending strength (silicone laminate 2) was evaluated in the same manner as in Example 1 except that the silicone varnish 2 was used instead of the silicone varnish 1.

A silicone laminate for measuring dielectric properties (silicone laminate having electrodes) was prepared in the same manner as in Example 1 except that the silicone varnish 2 was used instead of the silicone varnish 1, and the relative dielectric constant and the dielectric loss tangent were obtained. Was measured.
Table 5 shows the results.

Example 3 The dialkoxysilane (1) shown in Table 1, the water-soluble organic solvent (4), the metal-free hydrolyzed acid catalyst (3) and water were used in the amounts shown in Table 1. Others were the same as in Example 1 to obtain a mixed solution, and the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 3-a.

Apart from this, the phenyl or methyl trialkoxysilane (2), the water-soluble organic solvent (4), the metal-free hydrolyzing acid catalyst (3) and the water listed in Table 2 are listed in Table 2. A mixed solution was obtained in the same manner as in Example 1 except that the amount was used, and the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 3-b.

Next, the solution 3-a and the solution 3-b were used in place of the solution 1-a and the solution 1-b, and the temperature of the oil bath was raised to 95 ° C. over 110 minutes. In the same manner as in Example 1 to obtain a silicone oligomer solution, the silicone oligomer solution having an EL type rotational viscometer viscosity of 80.
When it reached 0 mPa · s and the intrinsic viscosity reached 6 cm ³ / g, it was allowed to cool to 60 ° C or lower. After that, the aliphatic monohydric alcohol solvent (B) and the condensation catalyst (C) containing a metal atom shown in Table 3 were added in the amounts shown in Table 3 and well stirred to obtain a silicone varnish. Identification of condensation products is I
R spectrum. The obtained silicone varnish is called silicone varnish 3.

The viscosity change of the silicone varnish 3 was measured in the same manner as in Example 1 after storage at 45 ° C. for 6 months. Table 4 shows the results.

A laminate for measuring flexural strength (silicone laminate 3) was evaluated in the same manner as in Example 1 except that the silicone varnish 3 was used instead of the silicone varnish 1.

A silicone laminate for measuring dielectric properties (silicone laminate having electrodes) was prepared in the same manner as in Example 1 except that the silicone varnish 3 was used instead of the silicone varnish 1, and the relative permittivity and the dielectric loss tangent were obtained. Was measured.
Table 5 shows the results.

[Example 4] The dialkoxysilane (1), the water-soluble organic solvent (4), the metal-free hydrolyzed acid catalyst (4) and water described in Table 1 were used in the amounts shown in Table 1. Others were the same as in Example 1 to obtain a mixed solution, and the hydrolyzed product was identified by IR spectrum. The obtained mixed solution is referred to as solution 4-a.

Separately from this, the phenyl or methyl trialkoxysilane (2), the water-soluble organic solvent (4), the metal-free hydrolyzing acid catalyst (3) and the water shown in Table 2 are shown in Table 2. A mixed solution was obtained in the same manner as in Example 1 except that the amount was used, and the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 4-b.

Next, the solution 4-a and the solution 4-b were used instead of the solution 1-a and the solution 1-b, and the temperature of the oil bath was raised to 95 ° C. over 110 minutes. In the same manner as in Example 1 to obtain a silicone oligomer solution, and the viscosity of the silicone oligomer solution in an EL type rotational viscometer is 50 m.
When the Pa · s and the intrinsic viscosity become 1 cm ³ / g,
It was allowed to cool to 60 ° C or lower. After that, the aliphatic monohydric alcohol solvent (B) and the condensation catalyst (C) containing a metal atom shown in Table 3 were added in the amounts shown in Table 3 and well stirred to obtain a silicone varnish. Identification of condensation products is IR
Performed on the spectrum. The obtained silicone varnish is called silicone varnish 4.

The viscosity change of the silicone varnish 4 after storage at 45 ° C. for 6 months was measured in the same manner as in Example 1. Table 4 shows the results.

A laminate for measuring bending strength (silicone laminate 4) was evaluated in the same manner as in Example 1 except that the silicone varnish 4 was used instead of the silicone varnish 1.

A silicone laminate for dielectric property measurement (silicone laminate having electrodes) was prepared in the same manner as in Example 1 except that the silicone varnish 4 was used instead of the silicone varnish 1, and the relative dielectric constant and dielectric loss tangent were obtained. Was measured.
Table 5 shows the results.

Example 5 In addition to the dialkoxysilane (1) shown in Table 1, the water-soluble organic solvent (4), the metal-free hydrolysis catalyst (3) and water, the amounts shown in Table 1 were used. In the same manner as in Example 1, a mixed solution was obtained, and the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 5-a.

The DMDPOS shown in Table 1 is dimethyldipropoxysilane.

Separately, the phenyl or methyl trialkoxysilane (2) listed in Table 2, the water-soluble organic solvent (4), the metal-free hydrolysis catalyst (3) and water are added in the amounts listed in Table 2. A mixed solution was obtained in the same manner as in Example 1 except that the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 5-b.

The PTrMOS shown in Table 2 is phenyltripropoxysilane.

Next, the solution 5-a and the solution 5-b were used instead of the solutions 1-a and 1-b, and the temperature of the oil bath was raised to 95 ° C. over 110 minutes. A silicone oligomer solution was prepared in the same manner as in Example 1, and the silicone oligomer solution had an EL type rotational viscometer viscosity of 100.
When it reached 0 mPa · s and the intrinsic viscosity was 7 cm ³ / g, it was allowed to cool to 60 ° C or lower. After that, the aliphatic monohydric alcohol solvent (B) and the condensation catalyst (C) containing a metal atom shown in Table 3 were added in the amounts shown in Table 3 and well stirred to obtain a silicone varnish. Identification of condensation products is I
R spectrum. The obtained silicone varnish is called silicone varnish 5.

The viscosity change of the silicone varnish 5 after storage at 45 ° C. for 6 months was measured in the same manner as in Example 1. Table 4 shows the results.

A laminated plate for measuring bending strength (silicone laminated plate 5) was prepared and evaluated in the same manner as in Example 1 except that the silicone varnish 5 was used instead of the silicone varnish 1.

Further, in the same manner as in Example 1 except that the silicone varnish 5 was used instead of the silicone varnish 1,
A silicone laminate for measuring dielectric properties (silicone laminate having electrodes) was prepared, and the relative permittivity and dielectric loss tangent were measured. Table 5 shows the results.

Example 6 In addition to the dialkoxysilane (1) shown in Table 1, the water-soluble organic solvent (4), the metal-free hydrolysis catalyst (3) and water, the amounts shown in Table 1 were used. In the same manner as in Example 1, a mixed solution was obtained, and the hydrolyzate was identified by IR spectrum. The obtained mixed solution is called 6-a.

Separately, the phenyl or methyl trialkoxysilane (2) listed in Table 2, the water-soluble organic solvent (4), the metal-free hydrolysis catalyst (3) and water are added in the amounts listed in Table 2. A mixed solution was obtained in the same manner as in Example 1 except that the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 6-b.

Next, the solution 6-a and the solution 6-b were used instead of the solutions 1-a and 1-b, and the temperature of the oil bath was raised to 95 ° C. over 110 minutes. A silicone oligomer solution was prepared in the same manner as in Example 1, and the silicone oligomer solution had an EL type rotational viscometer viscosity of 70 m.
When the Pa · s and the intrinsic viscosity become 2 cm ³ / g,
It was allowed to cool to 60 ° C or lower. After that, the aliphatic monohydric alcohol solvent (B) shown in Table 3 and the condensation catalyst (C) containing a metal atom are added in the amounts shown in Table 3 and well stirred to give a silicone varnish, which is condensed by IR spectrum. The reaction product was confirmed. The obtained silicone varnish is called silicone varnish 6.

The viscosity change of the silicone varnish 6 after storage at 45 ° C. for 6 months was measured in the same manner as in Example 1. Table 4 shows the results.

A laminate for measuring bending strength (silicone laminate 6) was evaluated in the same manner as in Example 1 except that the silicone varnish 6 was used instead of the silicone varnish 1.

A silicone laminate for measuring dielectric properties (silicone laminate having electrodes) was prepared in the same manner as in Example 1 except that the silicone varnish 6 was used in place of the silicone varnish 1, and the relative dielectric constant and dielectric loss tangent were obtained. Was measured.
Table 5 shows the results.

Example 7 The dialkoxysilane (1), the water-soluble organic solvent (4), the metal-free hydrolysis catalyst (3) and water shown in Table 1 were used in the amounts shown in Table 1. In the same manner as in Example 1, a mixed solution was obtained, and the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as solution 7-a.

DMDBOS shown in Table 1 is dimethyldibutoxysilane.

Separately, the phenyl or methyltrialkoxysilane (2) listed in Table 2, the water-soluble organic solvent (4), the metal-free hydrolysis catalyst (3) and water are added in the amounts listed in Table 2. A mixed solution was obtained in the same manner as in Example 1 except that the hydrolyzate was identified by IR spectrum. The obtained mixed solution is referred to as 7-b.

PTrBOS shown in Table 2 represents phenyltributoxysilane.

Next, the solution 7-a and the solution 7-b were used instead of the solutions 1-a and 1-b, and the temperature of the oil bath was raised to 95 ° C. over 110 minutes. A silicone oligomer solution was prepared in the same manner as in Example 1, and the viscosity of the silicone oligomer solution was 400 m in an EL type rotational viscometer.
When the Pa · s and the intrinsic viscosity become 4 cm ³ / g,
It was allowed to cool to 60 ° C or lower. After that, the aliphatic monohydric alcohol solvent (B) and the condensation catalyst (C) containing a metal atom shown in Table 3 were added in the amounts shown in Table 3 and well stirred to obtain a silicone varnish. Identification of condensation products is IR
Performed on the spectrum. The obtained silicone varnish is called silicone varnish 7.

The viscosity change of the silicone varnish 7 after storage at 45 ° C. for 6 months was measured in the same manner as in Example 1. Table 4 shows the results.

A laminate for measuring bending strength (silicone laminate 7) was evaluated in the same manner as in Example 1 except that the silicone varnish 7 was used instead of the silicone varnish 1.

A silicone laminate for measuring dielectric properties (silicone laminate having electrodes) was prepared in the same manner as in Example 1 except that the silicone varnish 7 was used instead of the silicone varnish 1, and the relative permittivity and dielectric loss tangent were obtained. Was measured.
Table 5 shows the results.

[0155]

[Table 1]

[0156]

[Table 2]

[0157]

[Table 3]

[0158]

[Table 4]

[0159]

[Table 5]

[Embodiment 8] A silicone varnish 4 and E glass fiber having a diameter of 9 μm were plain woven, and the surface was treated with aminosilane. A silicone / glass cloth ribbon type prepreg was manufactured.
The drying condition at this time was 120 ° C. for 10 minutes. The obtained ribbon type prepreg is called prepreg 8.

The prepreg 8 is wound around the outer circumference of a copper pipe having a diameter of 50 mm and a length of 5 m with right-hand and left-hand turns alternately and wound by hand in a spiral shape, and an aluminum foil coated with a silicone release agent is covered on it for heating. After winding the ribbon heater of (1) in a spiral shape, a heat insulating ribbon (glass cloth) for preventing heat diffusion was wound. Next, the ribbon heater is energized, the ribbon heater is heated to 180 ° C., left as it is for 60 minutes, then the ribbon heater temperature is further raised to 250 ° C. and left for 60 minutes, and then the cured prepreg is strongly bonded to the copper. I got a tube. This method is particularly effective for treating only a part of a pipe or a long pipe that has already been piped.

[Example 9] Silicone prepreg 4 produced in the same manner as in Example 4 was cut into 100 mm x 100 mm pieces, 30 sheets were piled up, and sandwiched with an aluminum foil coated with a silicone mold release agent at 170 ° C. After curing for 4 hours at 250 ° C for 1 hour,
A laminated plate having a thickness of about 7 mm was obtained. The obtained laminated plate is referred to as a silicone laminated plate 9.

The silicone laminate 9 was subjected to a bending strength test in accordance with JIS-6911 and found to be 12 Kgf /
A breaking strength of mm ² was obtained. In addition, this laminated board
After being kept for 90 days under the conditions described above, the bending strength was measured by the above method, and a breaking strength of 10 Kgf / mm ² was obtained.

In this construction method, a press machine is not particularly used,
The flat plate can be formed by its own weight. In addition, even complicated shapes can be molded with a simple mold, and the mold's own weight (0.1 Kgf
/ Cm ² ) can be sufficiently molded, so that a non-planar laminated plate such as a conformal substrate for radar can be easily obtained.

Example 10 To 500 g of Silicone varnish 1 produced in the same manner as in Example 1, 1700 g of spherical alumina particles (average particle size 26 μm) were added and kneaded well. This is spread on a glass plate with a polytetrafluoroethylene film attached to a thickness of about 0.3 mm, placed in a vacuum oven, and the pressure is reduced to 1 mmHg.
After left at room temperature for 1 hour, the temperature rising rate is 5 ° C /
In 40 minutes, the temperature was raised to 40 ° C., the temperature was held for 10 minutes, then the temperature was raised to 60 ° C., the temperature was held for 15 minutes, and the film was dried to prepare a film having no tack on the surface. Cut this film with a cutter knife so that it will be 200 mm square, and 1 mm of 200 mm square.
A thick aluminum plate was overlaid, a copper foil with a thickness of 35 μm was overlaid thereon, and vacuum pressed at 3 Kgf / cm ² pressure at 120 ° C. for 2 hours and at 170 ° C. for 3 hours to obtain a substrate (metal base substrate). . The thickness of the silicone resin layer of the obtained substrate was 112 μm. This substrate was punched into a disk shape with a diameter of 2 cm, the metal layers on both sides of the punched substrate were removed with an etching solution, and the thermal conductivity was measured by the xenon flash method to find that it was 4.0 W / mK. . The withstand voltage was 8 KV for 2 minutes.

The withstand voltage was 60 Hz in Fluorinert oil, using a device conforming to ASTM D149.
The voltage was increased to 0.5 KV / s and 8 KV, and then the voltage was held until dielectric breakdown occurred, and the energization time until dielectric breakdown was measured.

[Embodiment 11] A laminated board provided with a copper plate obtained in the same manner as in Embodiment 1 except that the silicone varnish 2 was used was prepared by a conventional method (through hole opening, panel copper plating, resist film attachment, exposure). Line & space 200μm and 500μm)
Of the migration test comb-shaped pattern on one side and the solder-immersion test line width of 1.27 mm and a length of 80 mm on the other surface with a space of 1.91 mm, with the comb-shaped pattern side facing inward. Stack in the same direction,
A silicone prepreg obtained in the same manner as in Example 2 was sandwiched between the two sheets and pressed at 170 ° C. for 3 hours at a pressure of 10 Kgf / cm ² , further taken out of the press, and then cured at 200 ° C. for 2 hours. I did. Next,
The diameter for connecting the inner comb-shaped pattern between the layers is 0.
8 2mm through-holes (2 pairs in each line & space), plating through-holes with resist, and printing solder resist 4
Layer printed circuit board. When this board was immersed in a solder bath at 260 ° C. for 5 minutes, no change was observed such as swelling of the pattern or deformation of the board, which was good. Further, the insulation of the comb-shaped electrodes was not deteriorated, and the conduction of the through holes was good. Therefore, it was found that the heat resistance of the substrate was good.

Example 12 10 parts of phenyltrimethoxysilane, 4.5 parts of dimethyldimethoxysilane, 5 parts of ethyl cellosolve and 0.2 part of a 10% phosphoric acid aqueous solution were charged, and the mixture was heated and reacted to give an intrinsic viscosity of 2.6 cm ^3. / G of the condensate, and dilute it with a mixed solvent of toluene: isopropanol = 1: 1 (weight ratio) so that the solid content is 40%,
A silicone varnish was prepared by adding 0.7 part of tetraisopropoxy titanium, and a BT resin copper clad laminate having a thickness of 1.57 mm and a length of 40 mm square (C manufactured by Mitsubishi Gas Chemical Co., Inc.)
CL-HL870), using a naphthoquinone diazide type positive resist AZ LP-10 (manufactured by Hoechst), line & space 100 μm, length 10 mm, width 8 mm.
4 rectangular zigzag patterns are prepared on one side, and the silicone varnish obtained in Example 3 is applied thereon at 800 rpm.
Spin coated for 1 minute. 10 minutes at 60 ℃, then 8
After drying at 0 ° C for 15 minutes, electroless thin copper plating is performed from the top, and then electrolytic plating is performed to obtain a positive resist AZ.
The interlayer via holes were patterned with LP-10 (manufactured by Hoechst). Interlayer buyer holes were provided in a total of 8 places with a diameter of 50 μm at positions contacting both ends of the zigzag pattern. By etching the lower layer plating using this resist pattern as a mask and peeling off the resist, a metal mask with holes only in the buyer hole portions was formed on the silicone resin prebague film. Next, toluene / methanol = 1: When immersed in a mixed solution of 1 (weight ratio) while applying ultrasonic waves, the lower silicone film was etched after about 2 minutes, so the solution was lifted from the solution and rinsed with IPA. Then peel off the copper plating, 1
By curing at 20 ° C. for 1 hour and further at 150 ° C. for 1 hour, a cured silicone resin film having a buyer hole was obtained. The film thickness of this cured film was 35 μm.

Next, electroless copper plating is uniformly formed from above to a thickness of 5 μm, LP-10 is applied on this, and LP-10 is removed only on the portion where the wiring pattern is to be formed. A pattern was formed. As for the pattern, each of the four rectangular zigzag patterns formed in the lower layer was two, and only two 100 μm-width lines for connecting were formed. Further, electrolytic plating was formed to have a thickness of 25 μm. Electrolytic plating was formed only on the surface where the electroless copper was exposed. LP
By removing -10 and lightly etching the copper,
A portion of only electroless copper plating (a portion having a small plating thickness) was removed to obtain a copper wiring pattern (this patterning method is called a semi-additive method). A silicone varnish was applied onto the copper pattern at 800 rpm for 1 minute, dried, and similarly etched to form a buyer hole. The hole was made at the same position as the hole except the buyer hole connected by the second layer. After curing the silicone resin in the same way,
Patterning was performed by the semi-additive method. The same pattern as the bottom layer was formed from the buyer hole portion. In other words, it is a pattern in which two conductive layers are sandwiched between two rectangular zigzag patterns. A portion other than the terminals (4 places) was covered with a photosensitive solder resist. In this way, the silicone resin film is used as an interlayer insulating film.
The layers were stacked to obtain a build-up three-layer board for an electronic module.

The electrical continuity between the terminals of this electronic module build-up three-layer substrate was good, and no change in appearance or electrical continuity was observed when immersed in a solder bath at 260 ° C. for 5 minutes.

Example 13 Methyltrimethoxysilane (9 parts), dimethyldimethoxysilane (4.5 parts), ethylcellosolve (5 parts) and phosphoric acid 10% aqueous solution (0.2 parts) were charged and heated to give an intrinsic viscosity of 2.4 cm ^3. / G of condensate,
It was diluted with a mixed solvent of toluene: isopropanol = 1: 1 (weight ratio) so as to have a solid content of 60%, 0.7 part of tetraisopropoxytitanium was added to prepare a silicone varnish, and E-glass cloth ( A fiber type 9 μm, plain weave, thickness 0.22) was impregnated with the above silicone varnish and air dried at 120 ° C. for 15 minutes to obtain a prepreg having a treatment ratio of 1.9. Fifteen sheets of the obtained prepreg were piled up, and the piled prepregs were heated at 170 ° C for 20 hours, then 200 ° C, 8K
It was pressed at a pressure of gf / cm ² for 1.5 hours. The thickness of the obtained laminated plate was 3.4 mm. This laminated plate was sandwiched between a prepreg and a copper foil in the same manner as in Example 1, 170 ° C., 8K
After pressing at gf / cm ² for 1.5 hours, it was taken out of the press and cured at 200 ° C. for 1 hour and 250 ° C. for 2 hours to obtain a copper-clad laminate. A multilayer board was obtained from this copper-clad laminate in the same manner as in Example 8.

When this was immersed in a solder bath at 260 ° C. for 5 minutes, no change in appearance such as pattern swelling or deformation of the substrate was observed, which was good. Further, the conduction of the comb-shaped electrodes was not observed, and the conduction of the through holes was good. Therefore, it was found that the heat resistance of the substrate was good.

[Example 14] 10 parts of phenyltrimethoxysilane, 7.0 parts of methylphenyldimethoxysilane,
Charge with 5 parts of ethyl cellosolve and 0.4 part of 10% aqueous solution of oxalic acid, and heat the mixture to obtain a condensate having an intrinsic viscosity of 2.2 cm ³ / g. Toluene: ethanol = 1 to make the solid content 65%. Dilute with a mixed solvent of 1 (weight ratio), add 0.6 parts of tetramethoxycytitanium to prepare a silicone varnish, and set spin coating conditions to 1000 rp.
A multi-layer substrate was obtained under the same conditions as in Example 12 except that m was set to 1 minute.

The electrical continuity between the terminals of this multilayer substrate is good, and
After immersion in a 60 ° C. solder bath for 5 minutes, no change in appearance or poor conduction was observed.

Example 15 To 500 g of Silicone varnish 2 produced in the same manner as in Example 2, 500 g of BaTiO ₃ crushed product (manufactured by Kojundo Chemical Laboratory Co., Ltd.) passed through a 100-mesh sieve was added and well stirred. After that, apply it to a square glass plate with a polytetrafluoroethylene film attached to a thickness of 0.5 mm and put it in a vacuum oven. Reduce the pressure to 1 mmHg and leave it at room temperature for 2 hours, then keep the reduced pressure. While raising the temperature to 40 ° C at a temperature rising rate of 5 ° C / min, hold this temperature for 15 minutes, then continue to 6
By raising the temperature to 0 ° C., holding this temperature for 10 minutes and drying, a hard film having no tack on the surface was obtained. The film was crushed with a hammer and passed through a 50 mesh sieve. 5 g of the obtained powder with an inner diameter of 20
mm, height 40 mm, packed in a cylindrical stainless steel mold,
While depressurizing the inside of the mold with a rotary pump, 10 kgf
The powder in the mold was compressed from above with a pressure of / cm ² . Then, the mold was heated to 170 ° C. at 5 ° C./minute and held at 170 ° C. for 1 hour. In this way, a disk-shaped molded body having a thickness of about 1 mm was obtained. The obtained molded body is further 200
After post-curing at 1 ° C. for 1 hour, Cu electrodes were vapor-deposited on both surfaces, and the dielectric properties were measured by the capacitance method. As a result, the relative dielectric constant was 800 and the dielectric loss tangent was 0.0004 at 1 MHz.

[Comparative Example 1] PTEOS 480 g, DM
DMOS 88.8 g, water 157 g, and trifluoromethanesulfonic acid 5% aqueous solution 10 g were placed in a 1 L beaker and stirred at 100 ° C., thickening started after 2 hours, and gelled after about 20 minutes, toluene, methanol, N.
-Insoluble in methylpyrrolidone, methyl ethyl ketone, tetrahydrofuran and a mixture thereof.

[Comparative Example 2] PTEOS 480 g, DM
DMOS (88.8 g), water (157 g) and phosphoric acid 10% aqueous solution (5 g) were placed in a 1 L beaker and stirred at 100 ° C. for 4 hours. 100 g of MIBK (methyl isobutyl ketone) was added to the obtained solution, glass cloth was impregnated with this solution, and dried at 120 ° C. for 5 minutes to obtain a prepreg. However, this prepreg has already been hardened, and this prepreg was cut into 5 cm square pieces, 10 sheets were stacked and pressed at 170 ° C. and 50 Kgf / cm ² , but a laminated plate through which a resin component flows can be produced. There wasn't.

[Comparative Example 3] PTEOS 480 g, DM
DMOS (88.8 g), water (157 g) and phosphoric acid 10% aqueous solution (5 g) were placed in a 1 L beaker and stirred at 100 ° C. for 4 hours. To the resulting solution was added 100 g of toluene, then 50 g of 10% sodium carbonate solution, the contents were transferred to a separating funnel, and only the toluene layer was extracted. The obtained toluene solution had excellent storage stability, and no change was observed even after storage at 25 ° C. for 3 months. However, zinc naphthenate (Zn-containing 8% mineral spirit solution)
When 5 g was added, gelation occurred at 25 ° C for 2 days. Therefore, a curing catalyst (zinc naphthenate or the like) had to be added to this resin composition immediately before use.

[0179]

【The invention's effect】

(A) (1) a dialkoxysilane having one or two kinds of a phenyl group and an alkyl group having 1 to 3 carbon atoms, and having an alkoxy group having 1 to 4 carbon atoms, (2) having 1 carbon atom
Phenyltrialkoxysilane or methyltrialkoxysilane having an alkoxy group of ~ 4, (3) an inorganic acid not containing a metal and containing at least one kind of chlorine atom and phosphorus atom, or having a PKa value of 0.8 to 6 Some organic acids,
And (4) the intrinsic viscosity at 25 ° C. obtained by dehydration condensation of water or a mixture of water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol under heating is 0.1 to 10 c.
The silicone varnish of the present invention comprising m ³ / g of a silicone oligomer, (B) an aliphatic monohydric alcohol or a mixed solvent containing the same, and (C) a condensation catalyst containing a metal atom is a coating, an interlayer insulating film, a prepreg or a laminate. High heat resistant silicone varnish suitable for boards and printed circuit boards. In addition, the characteristics of this silicone varnish are stable even after long-term storage.

When the solvent (4) consisting of water or water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol is a solvent containing a glycol ether, the hydrolyzed alkoxysilane and its condensate are It becomes easy to dissolve in a solvent containing ether, and a suitable silicone varnish can be obtained.

An inorganic acid containing no metal and containing at least one kind of chlorine atom and phosphorus atom or an organic acid (3) having a PKa value of 0.8 to 6 is phosphoric acid, hydrochloric acid, oxalic acid, By using acetic acid or formic acid, the alkoxysilane can be polycondensed with almost no gelation, and a suitable silicone varnish can be obtained.

The condensation catalyst (C) containing a metal atom is an organic acid tin salt, an organic acid lead salt, an organic acid cobalt salt, an organic acid zinc salt, an organic acid manganese salt, an organic acid iron salt or a carbon number 1 to 1
A monotitanium compound containing an alkoxy group of 4 or an alkoxy group of 1 to 4 carbon atoms and an acetoxy group, and the organic acid is heptanoic acid, octanoic acid, nonanoic acid or naphthenic acid, the condensation catalyst for silanol condensation. Since the catalytic effect is great, a suitable silicone varnish can be obtained.

A silicone varnish-impregnated prepreg obtained by impregnating a reinforcing cloth, a non-woven fabric or a filament with the above-mentioned silicone varnish and drying it to a tack-free state has excellent adhesion to a substrate or between prepregs. It is suitable for providing a heat insulating layer or insulating film on the surface, or for forming a laminated plate. Further, since the prepreg impregnated with the silicone varnish is dried to a tack-free state, it can be stored repeatedly. Also, in this prepreg impregnated with silicone varnish that has been dried to be tack-free, there are residual aliphatic monohydric alcohols that are effective in maintaining the storage stability of the prepreg, and these inhibit silanol condensation. The storage stability of the prepreg is also good. Further, this silicone varnish impregnated prepreg is suitable for providing a heat insulating layer or an insulating film on the surface of a base material, or for forming a laminated board, and further, no particularly strong pressure is required for adhesion and lamination. , Sufficient adhesive strength and interlayer strength can be obtained without using a special device such as a press.

Since the prepreg impregnated with the silicone varnish has excellent adhesiveness between the prepregs, a plurality of the prepregs can be laminated and heat-cured to obtain a suitable composite material.

Since the silicone varnish-impregnated prepreg has excellent adhesion to the base material, it can be covered with or wrapped around the base material and heat-cured to obtain a suitable composite material.

The composite material obtained by stacking a plurality of the silicone-impregnated prepregs and thermosetting them has excellent mechanical strength, has a lower dielectric constant than the glass-epoxy laminate,
It has a characteristic that the dielectric loss is small. Therefore, by providing a metal layer made of copper, aluminum or the like on both surfaces or one surface of the composite material, the composite material can be suitably used as a laminated board for a printed circuit board.

A printed circuit board can be manufactured by forming a circuit on one side or both sides of the above-mentioned laminated board for a printed circuit board, and further, two or more, preferably 2 to 15 printed circuit boards thus manufactured. By stacking, sandwiching the silicone varnish-impregnated prepreg between the printed circuit board and the printed circuit board, and performing hot press molding,
A printed circuit board having a multilayer structure can be manufactured.

The cured product of the silicone varnish is superior in heat resistance to the epoxy resin and has a low dielectric constant.
Since it has low dielectric loss, it is suitable as an interlayer insulating film for build-up boards for electronic circuit modules.

In the silicone varnish, instead of producing a prepreg, a mixture of silicone varnish and inorganic powder, particles or whiskers is produced and heated to remove the solvent to obtain a film-like substance, or a solid substance. You may use it after changing. This film-like material or a crushed solid is suitable for molding a solid having a complicated shape.

Examples of the composite molded body include, for example, alumina particles alone or a high heat conductive resin material containing alumina particles and boron nitride particles, and a high dielectric constant capacitor material containing high dielectric constant particles such as TiO ₂ particles. Can be given. A heat dissipation printed circuit board can be manufactured by using the high thermal conductive resin material, adhering it to a metal plate-like material such as an aluminum substrate, and further adhering a copper foil thereto. This heat dissipation printed board is suitable for a component mounting board such as a power module that requires heat dissipation. Further, it is possible to manufacture a sandwich-type capacitor component by sandwiching the high dielectric constant capacitor material with electrodes. In addition, the high dielectric constant capacitor material is formed into a film and directly attached to a substrate, so that it can be suitably used as a coupling capacitor.

(A) (1) Phenyl group and carbon number 1 to
A dialkoxysilane having one or two of the alkyl groups of 3 and having an alkoxy group having 1 to 4 carbon atoms,
(2) Phenyltrialkoxysilane or methyltrialkoxysilane having an alkoxy group having 1 to 4 carbon atoms, (3) an inorganic acid not containing a metal and containing at least one kind of chlorine atom and phosphorus atom, or having a PKa value 0.8 ~
6, and (4) water or a mixture of water or a solvent consisting of water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol, is dehydrated and condensed under heating to obtain an intrinsic viscosity of 0. Produced by a method for producing a silicone varnish, characterized in that (B) an aliphatic monohydric alcohol or a mixed solvent containing the same and (C) a condensation catalyst containing a metal atom are added after obtaining 1 to 10 cm ³ / g of a silicone oligomer. The possible silicone varnish of the present invention is a high heat resistant silicone varnish suitable for coatings, interlayer insulating films, prepregs, laminates, printed boards and the like. Further, this silicone varnish has stable properties even after long-term storage.

In the above-mentioned production method, the solvent (4) consisting of water or water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol is a solvent containing glycol ether, whereby the hydrolyzed alkoxysilane and its condensation are obtained. The body is easily dissolved in the solvent containing this glycol ether, and a suitable silicone varnish can be obtained.

In the above production method, an inorganic acid containing no metal and containing at least one kind of chlorine atom and phosphorus atom or an organic acid (3) having a PKa value of 0.8 to 6
By using phosphoric acid, hydrochloric acid, oxalic acid, acetic acid or formic acid, the alkoxysilane can be polycondensed with almost no gelation, and a suitable silicone varnish can be obtained.

In the above production method, the condensation catalyst (C) containing a metal atom is an organic acid tin salt, an organic acid lead salt, an organic acid cobalt salt, an organic acid zinc salt, an organic acid manganese salt, an organic acid iron salt or A monotitanium compound having an alkoxy group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms and an acetoxy group, wherein the organic acid is heptanoic acid, octanoic acid,
By using nonanoic acid or naphthenic acid, this condensation catalyst has a large catalytic effect on silanol condensation.
A suitable silicone varnish can be obtained.

[0195] A mixture of the above-mentioned silicone varnish and inorganic powder, particles or whiskers is heated and desolvated to obtain a film-like product or a solid product, which is crushed by a hot press or a molding machine. By the method for producing a composite molded article characterized by, a solid having a complicated shape can be molded.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hiroshi Adachi 2-3-3 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd. (72) Inventor Shigeru Kubota 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd. (72) Inventor Misaya Kobayakawa 2-6-1, Miwa, Mita, Hyogo Prefecture Ryoden Kasei Co., Ltd. (72) Inventor, Koji Hatanaka 2-6-1, Miwa, Mita, Hyogo Prefecture Denka Kasei Co., Ltd.

Claims (16)

[Claims] 1. (A) (1) Phenyl group and carbon number 1
A dialkoxysilane having one or two kinds of alkyl groups of 1 to 3 and an alkoxy group having 1 to 4 carbon atoms,
(2) Phenyltrialkoxysilane or methyltrialkoxysilane having an alkoxy group having 1 to 4 carbon atoms, (3) an inorganic acid not containing a metal and containing at least one kind of chlorine atom and phosphorus atom, or having a PKa value 0.8 ~
The organic viscosity of 6 and (4) water or a mixture of water and a solvent consisting of a water-soluble organic solvent excluding the aliphatic monohydric alcohol is dehydrated and condensed under heating to obtain an intrinsic viscosity at 25 ° C. of 0. Silicone varnish comprising 1 to 10 cm ³ / g of silicone oligomer, (B) an aliphatic monohydric alcohol or a mixed solvent containing the same, and (C) a condensation catalyst containing a metal atom. 2. The silicone varnish according to claim 1, wherein the solvent (4) comprising water or water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol is a solvent containing a glycol ether. 3. An inorganic acid containing no metal and at least one kind of chlorine atom and phosphorus atom, or having a PKa value of 0.
The silicone varnish according to claim 1 or 2, wherein the organic acid (3) of 8 to 6 is phosphoric acid, hydrochloric acid, oxalic acid, acetic acid or formic acid. 4. A condensation catalyst (C) containing a metal atom comprises an organic acid tin salt, an organic acid lead salt, an organic acid cobalt salt, an organic acid zinc salt, an organic acid manganese salt, an organic acid iron salt or a carbon number 1 to 1. Four
4. The silicone varnish according to claim 1, which is a monotitanium compound containing an alkoxy group or an alkoxy group having 1 to 4 carbon atoms and an acetoxy group, and the organic acid is heptanoic acid, octanoic acid, nonanoic acid or naphthenic acid. . 5. A silicone varnish-impregnated prepreg obtained by impregnating a reinforcing cloth, a non-woven fabric or a filament with the silicone varnish according to claim 1, 2, 3 or 4 and drying the varnish to a tack-free state. 6. A composite material obtained by stacking a plurality of silicone varnish-impregnated prepregs according to claim 5 and thermosetting them. 7. A composite material obtained by covering or winding a silicone varnish-impregnated prepreg according to claim 5 on a base material and thermally curing the same. 8. A laminate for a printed circuit board, wherein a metal layer is provided on both surfaces or one surface of the composite material according to claim 6. 9. A prepreg impregnated with a silicone varnish according to claim 5, wherein 2 to 15 printed boards, each of which has a circuit formed on one side or both sides, are manufactured by using the laminated board for a printed board according to claim 8. A printed circuit board having a multi-layer structure obtained by sandwiching and sandwiching and hot pressing. 10. A film or solid obtained by desolvating a mixture of the silicone varnish according to claim 1, 2, 3, or 4 with inorganic powder, particles or whiskers and crushing the solid. A composite molded body obtained by molding. 11. A build-up multilayer substrate for an electronic circuit module, which uses the cured product of the silicone varnish according to claim 1, as an interlayer insulating film. 12. A dialkoxysilane having (A) (1) one or two kinds of a phenyl group and an alkyl group having 1 to 3 carbon atoms and having an alkoxy group having 1 to 4 carbon atoms, (2) ) Phenyltrialkoxysilane or methyltrialkoxysilane having an alkoxy group having 1 to 4 carbon atoms, (3) an inorganic acid not containing a metal and containing at least one kind of chlorine atom and phosphorus atom, or having a PKa value of 0. 8
To an organic acid of 6 and (4) water or a mixture of water and a solvent consisting of a water-soluble organic solvent excluding the aliphatic monohydric alcohol under heating, the intrinsic viscosity at 25 ° C. is 0. A method for producing a silicone varnish, characterized in that (B) an aliphatic monohydric alcohol or a mixed solvent containing the same and (C) a condensation catalyst containing a metal atom are added after obtaining 1 to 10 cm ³ / g of a silicone oligomer. 13. The method for producing a silicone varnish according to claim 12, wherein the solvent (4) comprising water or water and a water-soluble organic solvent excluding the aliphatic monohydric alcohol is a solvent containing glycol ether. 14. An inorganic acid containing no metal and at least one kind of chlorine atom and phosphorus atom or an organic acid (3) having a PKa value of 0.8 to 6 is phosphoric acid, hydrochloric acid or oxalic acid. The method for producing a silicone varnish according to claim 12 or 13, wherein the silicone varnish is acetic acid or formic acid. 15. The condensation catalyst (C) containing a metal atom comprises an organic acid tin salt, an organic acid lead salt, an organic acid cobalt salt, an organic acid zinc salt, an organic acid manganese salt, an organic acid iron salt or a carbon number of 1 to 1.
15. A silicone according to claim 12, 13 or 14, which is a monotitanium compound containing an alkoxy group having 4 or an alkoxy group having 1 to 4 carbon atoms and an acetoxy group, and the organic acid is heptanoic acid, octanoic acid, nonanoic acid or naphthenic acid. How to make varnish. 16. A pulverized film-like material or solid obtained by desolventizing a mixture of the silicone varnish according to claim 1, 2, 3, or 4 with inorganic powder, particles or whiskers by heating. Is molded by hot pressing or by a molding machine.