JPH01207986A - Compound material for printed wiring board - Google Patents

Abstract

PURPOSE:To make a compound material for a printed wiring board which has excellent basic characteristics and is thin but has a good mechanical strength, especially a good tensile strength, meeting requirements for a high- density printed wiring board, by coating and/or impregnating a curing phosphazene compound on a basic material and by curing it. CONSTITUTION:As a curing phosphazene compound, a cured resin can be used properly, which is made by curing and polymerizing a mixture of one or two kinds of compounds expressed by a general expression [NPXaYb]n. In this expression, X and Y are polymerization curing radicals or non-polymerization curing radicals, (a) and (b) are integers between 0 and 2 (a+b=2), and (n) is an integer not less than 3. A compound material for a printed wiring board can be made by coating and/or impregnating a curing phosphazene compound on a basic material and curing it. By this method, insulation, heat resistance, chemical stability, abrasion resistance and durability of the compound material for a printed wiring board are made excellent and also a mechanical strength including a tensile strength can be remarkably increased.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a composite material for printed wiring boards, and more specifically, the present invention relates to a composite material for printed wiring boards, and more particularly, it has excellent mechanical strength such as tensile strength, and has a base material made of wood. The present invention relates to a composite material for printed wiring boards which is advantageous in practical use and maintains appropriate flexibility.

[Prior Art and its Problems] Laminated boards such as copper-clad laminates are known as printed wiring boards that have been widely used in the electrical and electronic equipment fields.

This laminate is generally made of paper fiber base materials such as kraft paper and mixed paper, inorganic paper base materials such as glass cloth and alumina paper, polyimide resins, phenol resins, epoxy resins, and polyester resins. Using a resin base material such as resin, a composite laminate material made by impregnating the base material with the above resin, or a metal foil such as copper foil, these can be fabricated into various structures depending on the purpose. It is manufactured by stacking, adhering, or press-bonding lamination so that it becomes like that, or by vapor-depositing or plating a conductive metal on the laminate or laminate itself.

However, in recent years, printed wiring boards have been required to have higher density, and this trend is expected to become even stronger in the future. Therefore, the size of wiring board chips is becoming smaller and the laminate itself is becoming more multi-layered, and accordingly, laminate materials are required to be thinner and more durable.

Conventionally, as such a thin but relatively strong laminated material,
The above-mentioned crow cloth, paper thread base material, inorganic paper base material,
In the above, laminated materials impregnated with curable resins such as epoxy resins and phenol resins, or resins such as polyimide resins have been used, but these laminated materials
When further increasing the density, there was a problem that the mechanical strength and the like were still insufficient.

The present invention has been made based on the above circumstances.

The purpose of the present invention is to provide a thin yet mechanically resistant material that has excellent basic properties such as insulation, heat resistance, alkali resistance, acid resistance, abrasion resistance, and durability, and that can meet the demands for higher density printed wiring boards. The object of the present invention is to provide a composite material for printed wiring boards that has excellent strength, especially tensile strength, and does not reduce the appropriate flexibility of the base material.

[Means for Solving the Problems] As a result of extensive research in order to solve the above-mentioned problems, the present inventors have found that a substrate having a specific cured resin product, that is, a cured product of a curable phosphazene compound, is suitable for printing. It has been discovered that the above-mentioned object can be satisfied as a material for wiring boards, and the present invention has been completed.

That is, the configuration of the present invention for achieving the above object is as follows:
A composite material for a printed wiring board characterized by coating and/or impregnating a curable phosphacene compound onto a base material and curing the same.

The base material used in the present invention is not particularly limited, and conventionally used base materials for printed wiring boards can be used.

Specific examples include glass fiber paper base materials such as glass cloth, glass mat, glass paper, and quartz fiber; paper thread base materials such as kraft paper, linter paper, mixed paper, and antimony paper; and inorganic paper base materials such as alumina paper. Base materials, synthetic resin fiber sheets such as polyester m fibers, polyamide fibers, and polyaramid fibers, composite base materials such as glass-mixed paper, etc. can be suitably used.

The shape and thickness of the base material are not particularly limited and can be appropriately selected to suit the printed wiring board.

For example, the thickness of the base material cannot be uniformly defined because it varies depending on its type, laminated structure, and purpose of use, but it is usually suitable for it to be in the range of, for example, 0.005 to 1.0 am.

The curable phosphazene compound used in the present invention has the following general formula (I) [N PXa Y b ].・・・・・・・・・・・・(I
I (wherein, X and Y represent a polymerizable curable group or a non-polymerizable curable group, and at least one of X and Y represents a polymerizable curable group, and X and Y are the same) It is okay to be different.

a and b each represent an integer from O to 2, and a
+b=2. Further, n represents an integer of 3 or more,
Preferably 3≦n≦18, particularly preferably n=
3 or 4. A cured resin product obtained by polymerizing and curing one type or a mixture of two or more of the compounds represented by ) can be suitably used.

Examples of the polymerizable curable group used as X and/or Y in the general formula (I) include groups containing a polymerizable double bond such as an acrylic group, a methacryl group, a vinyl group, and an allyl group. Among them, a group containing an acryloyloxy group and/or a methacryloyloxy group, for example, the following general formula (II) (wherein Z represents a hydrogen atom or a methyl group,
R represents an alkylene group having 1 to 12 carbon atoms. This alkylene group R may be linear or branched. ) Specific examples of the group represented by the general formula (II) are:
For example, 2-hydroxyethyl methacrylate-1-,2-
Hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 6-hydroxy-3-
Methylhexyl methacrylate, 5-hydroxyhexyl methacrylate, 3-hydroxy-2-t-butylpropyl methacrylate, 3-hydroxy-2,2-dimethylhexyl methacrylate, 3-hydroxy-2-methyl-ethylpropyl methacrylate and 12- Residues obtained by removing hydrogen atoms from hydroxyl groups in methacrylates such as hydroxydodecyl methacrylate, as well as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-
Hydroxybutyl acrylate, 4-hydroxyethyl acrylate, 5-hydroxypentyl acrylate,
6-hydroxy-3-methylhexyl acrylate, 5
-Hydroxyhexyl acrylate, 3-hydroxy-
Hydrogen atoms are removed from the hydroxyl groups in acrylates such as 2-t-butylpropyl acrylate, 3-hydroxy-2,2-dimethylhexyl acrylate, 3-hydroxy-2-methyl-ethylpropyl acrylate, and 12-hydroxydodecyl acrylate. Residues can be mentioned. A particularly preferred group is a (meth)acrylate residue in which Z in the above formula (1) is a hydrogen atom or a lower alkyl group having 1 to 4 carbon atoms, and R is a lower alkylene group having 1 to 4 carbon atoms; Preferred groups are 2-hydroxyethyl methacrylate residues and 2-hydroxyethyl acrylate residues.

However, when comparing the various hydroxyalkyl methacrylate residues and hydroxyalkyl acrylate residues, the hydroxyalkyl acrylate residues are considered to be more preferable.

This is because the crosslinking rate increases.

Further, examples of the non-polymerizable curable group that can be used as X or Y in the general formula (I) include a phenoxy group, a halogenated phenoxy group, an alkoxy group, a halogenated alkoxy group, and an amino group. Can be done.

In the present invention, among the curable phosphazene compounds, cyclic phosphazene compounds in which n in the general formula (I) is 3 or 4 or mixtures thereof are particularly preferred.

This is because by using a cured resin obtained by polymerizing and curing the cyclic compound, a composite material for printed wiring boards particularly excellent in heat resistance can be obtained.

Specific examples of the cyclic phosphazene compound in which n in the general formula (I) is 3 include, for example, 1°1.3,3,
5.5-hexa(2-methacryloylethylenedioxy)cyclotriphosphazene, 1,1,3,3°5.5-
Examples include hexa(2-acryloylethylenedioxy)cyclotriphosphazene.

Further, as specific examples of the cyclic phosphazene compound in which n in the general formula (I) is 4, for example, 1, 1, 3
,3,5,5. ．． 7.7-octa(2-methacryloylethylenedioxy)cyclotetraphosphazene, 1,1
, 3,3,5,5.7.7-octa(2-acryloylethylenedioxy)cyclotetraphosphazene and the like.

Note that the method for producing the phosphazene compound is already known, and the curable phosphazene compound used in the present invention can also be produced according to the known method. For example, by reacting hexachlorocyclotriphosphazene with 2-hydroxyethyl methacrylate, a phosphazene compound in which part or all of the chlorine in hexachlorocyclotriphosphazene is substituted with a 2-hydroxyethyl methacrylate residue can be obtained. Note that it is preferable that all chlorine be replaced here,
Some chlorine may remain.

In this reaction, it is advantageous to use a tertiary amine in order to promote the dechlorination reaction. Examples of the tertiary amine include trimethylamine, triethylamine, triisopropylamine, tri-n-propylamine, tri-n-butylamine, pyridine, and N,N,N-tetraethylenediamine, among which pyridine is preferred. It is.

Moreover, this reaction is usually carried out in an organic solvent that does not contain water. Examples of the organic solvent used include benzene, toluene, xylene, chloroform, cyclohexane, methylene chloride, and tetrahydrofuran, which can be used alone or in combination.

In the present invention, it is preferable to use a trimer (hexachlorocyclotriphosphazene), a tetramer, or an oligomer of dichlorophosphazene as the glolophosphazene compound that is a starting material for producing the curable phosphazene compound. This is because the crosslinking density in the cured product of the curable phosphazene compound obtained using such a telomer or oligomer can be easily controlled.

The amount of the curable phosphazene compound used to obtain the printed wiring board composite of the present invention depends on the type of substrate used,
Although it cannot be uniformly prescribed because it varies depending on the purpose of use, the number of calendars and the structure of the laminate when making it into a laminate, it is usually 10110 per 100 parts by weight of the base material used.
-6 to 10 parts by weight is preferred.

If the amount used is too small, the resulting printed wiring board composite will not have sufficient mechanical strength and will not be sufficiently effective in downsizing and increasing the density of the board. If the amount is too large, the base material may not be able to maintain its inherent flexibility.

The composite for a printed wiring board in the present invention can be produced by coating and/or impregnating the curable phosphazene compound on the base material and curing it.

In addition, a polymerizable curable compound may be made to coexist with the curable phosphazene compound during pre-coating and/or impregnation.

Examples of the polymerizable curable compound include methyl acrylate, hydroxyethyl acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, a mixture of tetraethylene glycol diacrylate and methacrylate, glycidyl acrylate, 2,2゛−
Bis(acryloxyphenyl)propane, 2,2'-bis[4-(3-methacryloxy)-2-hydroxypropoxyphenyl]propane, vinyl esters of carboxylic acids (e.g. vinyl acetate, vinyl stearate, etc.)
and ethylenically unsaturated dicarboxylic acids (e.g. fumaric acid, maleic acid.

maleic anhydride, itaconic acid, itaconic anhydride, etc.).

Further, the curable phosphazene compound may optionally contain commonly used additives, such as a crosslinking agent, a molecular weight regulator, an antioxidant such as an antioxidant, a plasticizer, and the like.

In the method of the present invention, the curable phosphazene compound is usually mixed with a photopolymerization initiator or a thermal polymerization initiator described later, or if desired, other polymerizable curable compounds and additives as described above are mixed therein. Alternatively, the added material is coated or impregnated onto the base material.

This coating and/or impregnation may be carried out on a predetermined portion of the substrate used, or may be carried out over the entire substrate, for example from one side of the substrate or from both sides.

When performing this coating and impregnation, the curable resin used can be dissolved or dispersed using a diluent or solvent if desired, and usually, especially when the curable phosphazene compound used has a high viscosity, , it is desirable to use a diluent or solvent as described above.

As this diluent or solvent, a water-free organic solvent is used.

Examples of organic solvents include ketones (e.g., methyl ethyl ketone, methyl imbutyl ketone, etc.), aromatic organic solvents (e.g., benzene, toluene, xylene, etc.), chlorinated organic solvents (e.g., chloroform, methylene chloride, etc.), Alcohols (e.g. methanol, ethanol, alcohol, isopropyl alcohol,
isobutyl alcohol, etc.), alicyclic organic solvents (for example, cyclohexane, etc.), and tetrahydrofuran, and these can be used alone or in combination. Among these, ketones such as methyl ethyl ketone and methyl isobutyl ketone, or mixed solvents of ketones and alcohols such as a mixed solution of methyl isobutyl ketone and isopropyl alcohol or isobutyl alcohol are preferred.

The mixing ratio of the curable phosphazene compound and the organic solvent is usually preferably set within the range of 1:10zlO' to 1:10 by weight.

The coating and/or impregnation method includes:
Known methods such as a coating method, a spray method, a dipping method, etc. can be appropriately employed.

In addition, by either the coating operation and the impregnation operation, or a combination of re-operation, a film of the curable phosphazene compound is formed at least on the surface of the base material, and further, in some cases, the curable phosphazene compound is permeated into the inside of the base material. let

The degree to which the inside of the base material is impregnated with the curable phosphazene compound may be appropriately determined depending on the desired strength of the composite material for printed wiring boards.

When the base material has a multilayer structure, each single layer may be coated and/or impregnated before each layer is formed into a multilayer structure, or the coating and/or impregnation may be performed after each single layer is stacked to form a laminate. You can do it.

After coating or impregnating as described above, the diluent or solvent used is evaporated and removed by drying under reduced pressure, heat drying, air drying, or a combination thereof. Note that this drying process is
If a diluent or solvent is not used, it is not necessary to perform this drying process, and if a heat curing method is used, this drying process may be replaced by a heat curing process.

It is possible. Next, a curing treatment is performed to polymerize and harden the curable phosphazene compound or other curable resin optionally used together with the curable phosphazene compound to produce a cured product.

As a method for this curing treatment, it is possible to use a room temperature curing method, but considering the characteristics of the composite material for printed wiring boards obtained and the curing time of the curable phosphazene compound, it is possible to use a heat curing method, an electron beam curing method, A radiation curing method using ultraviolet rays or visible light can be suitably employed, with heat curing methods and ultraviolet curing methods being particularly preferred.

Note that a curing method that uses these methods in combination can also be adopted.

When using a curing method using electron beams, ultraviolet rays, or visible light, examples of the polymerization initiator (photosensitizer) used include l-hydroxycyclohexyl phenyl ketone,
Dibenzoyl, benzoyl methyl ether, benzoylethyl ether, p-chlorobenzophenone, p-methoxybenzophenone, benzoyl peroxide, di-tert-butyl peroxide and camphorquinone can be mentioned, and these are usually used alone or in parts by weight. The value is set within the range of 0.05 to 5.0 parts by weight.

Further, when using a room temperature curing method or a heat curing method, it is usually preferable to use a peroxide-based compound or a combination thereof with an amine-based compound as a polymerization initiator.

Examples of peroxide compounds include benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4
Examples include -dichlorobenzoyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, t-butyl peroxyacetate, and t-butyl peroxybenzoate.

Further, examples of amine compounds include N.

N-jetanol-p-)luidine, dimethyl-p-)
Luidine, P-toluidine, methyl, amine, t-butylamine, methylethylamine, diphenylamine, 4
．． Examples include 4'-dinitrodiphenylamine, 0-nitroaniline, p-bromoaniline, and 2,4.6-)ribromoaniline.

In this case, the amount of the peroxide compound to be used is preferably set to a value usually in the range of 0.05 to 5.0 parts by weight per 100 parts by weight of the phosphazene compound.

Further, the amount of the amine used is preferably within the range of usually 0.05 to 5 parts by weight per 100 parts by weight of the curable phosphazene compound used.

The conditions for this curing treatment cannot be uniformly prescribed because they vary depending on other conditions such as the type and amount of the curable phosphazene compound used and the type and amount of the polymerization initiator used, but the heat curing method When used, for example, usually within a temperature range of 60 to 160°C, preferably 90 to 120°C, for usually 0.1 to 2 hours, preferably 0.5
On the other hand, when a curing method using ultraviolet rays is used, a commonly used ultraviolet source such as a high-pressure mercury lamp is used to emit ultraviolet rays at ~5000mJ/cm2,
A method of continuous or intermittent irradiation, preferably at an illuminance of 2500 to 3500 IIJ/c112, usually for 5 to 300 seconds, preferably 10 to 200 seconds, can be suitably applied.

As described above, a composite material for a printed wiring board is obtained by coating and/or impregnating a base material with a curable phosphazene compound.

Thereafter, a conductive layer is formed on the surface of the composite material for a printed wiring board by a known method to obtain a printed wiring board.

In addition, the composite material for printed wiring boards of the present invention obtained using a base material of a single layer structure or a laminated structure is used as a unit layer,
Two or more of these unit layers are used, or one layer is used as desired.
A layer or two or more layers of other known laminate materials, such as the base material, resin-based laminates, inorganic laminates, composite laminates, metal foils, etc., may be used by known laminate processing methods, such as adhesives. Alternatively, a printed wiring board can also be manufactured by employing an adhesive lamination method using an adhesive sheet, a thermocompression lamination method, a metal vapor deposition method, an electroless plating method, or a combination thereof.

The composite material for printed wiring boards of the present invention has excellent basic properties such as insulation, and is also extremely superior in mechanical strength such as tensile strength. Therefore, the composite material itself can be made thinner than conventional ones. Therefore, when the substrate has a laminated structure, it is possible to increase the number of layers and reduce the size of the substrate, thereby realizing higher density of the printed wiring board.

[Effects of the Invention] According to the present invention, it has excellent insulation properties, heat resistance, chemical stability, abrasion resistance, durability, etc., and has significantly improved mechanical strength such as tensile strength. It has excellent properties such as maintaining the appropriate flexibility that the wood has naturally.
Therefore, it is possible to provide a composite material for printed wiring boards that is extremely advantageous in practice and can be used to make printed wiring boards for various uses, particularly high-density printed wiring boards.

[Example 1] The following examples and comparative examples of the present invention are shown below. (Example 1) 86.8 g of hexachlorocyclotriphosphazea was dissolved in 338 g of dehydrated benzene in a 2-liter flask.

To this benzene solution 155 g of pyridine and 0.23
g of hydroquinone was added and stirred in a nitrogen stream.

Separately, 200ml of 2-hydroxyethyl methacrylate was 2371ml! ; L of benzene, this solution was added dropwise into the flask, and the reaction was carried out at 50° C. for 20 hours. After the reaction was completed, pyridine hydrochloride was removed by filtration.

The filtrate was washed with water and then dried using Glauber's salt, and the solvent was removed by vacuum distillation to give a viscosity of 1.1.3° to 3.5°.
5-hexa(methacryloylethylenedioxy)cyclotriphosphazene (curable phosphazene compound A) 2
00g was obtained.

Yield: 88°3% Curable phosphazene compound reinforced base material (reinforcing material A) Curable phosphazene compound A prepared above was dissolved in methyl ethyl ketone to make a 0.5% by weight solution. Benzphenone was cured into this solution. 3 for phosphazene compound A
A solution A was added in parts by weight.

Four types of base materials (kraft paper, polyamide fiber, alumina paper, and glass cloth) shown in Table 1 were each impregnated with this solution A. After impregnation, the solvent was removed by drying in a dryer at 90°C for 10 minutes, and then 2,960
+wJ/c+m2c7) Both sides of each base material were irradiated with ultraviolet rays for 150 seconds, and four types of curable resin reinforced base materials (
A reinforcing material A (cured amount) was obtained.

The tensile strength of each of the four types of reinforcing material A-based cured products obtained was measured.

The results are shown in Table 2.

(Example 2) Production side of curable phosphazene compound B A thermometer, a stirring device, a dropping funnel, and a condenser were attached to 2! ; In a L flask, add 30% tetrahydrofuran.
0 ml and 25.5 g of sodium metal were added.

In this reaction solution, 104.3 g of phenol (1,11
After dropping, the mixture was refluxed for 3 hours to obtain a solution containing sodium phenolate.

Next, 193 g (0
, 555 mol) of hexachlorocyclotriphosphazene was added dropwise to the tetrahydrofuran solution containing the phenolate obtained above, and then reacted under reflux for 4 hours.

After the reaction, the temperature was returned to room temperature and pyridine 325 was added to the reaction solution.
g (4.46 mol), 381 g (2.45 mol) of 2-hydroxyethyl methacrylate was gradually added dropwise from the dropping funnel. The obtained reaction solution was heated to 60° C. in a hot water bath, and a heating and stirring reaction was carried out for 8 hours. After the reaction was completed, the precipitated crystals were filtered off, the solvent in the resulting filtrate was removed by distillation under reduced pressure, and the residue was sufficiently dried to obtain 452 g of the desired yellow liquid.

Production example of curable phosphacene compound reinforced base material (reinforcing material B-based cured product) The curable phosphacene compound B obtained above was dissolved in methyl ethyl ketone to form a 0.5% by weight solution. Add benzoyl peroxide to this solution and add curable phosphazene compound B 1
Solution B was prepared by adding 0.3 parts by weight per 00 parts by weight.

Four types of base materials shown in Table 1 were each impregnated with this solution B. After impregnation, heat and vacuum dry at 120°C for 30 minutes,
Four types of target curable phosphazene compound-reinforced base materials (reinforcement material B-based cured products) were obtained.

A tensile test similar to Example 1 was conducted on these cured reinforcing material B products.

The results are shown in Table 2.

(Comparative Example 1) Four types of base materials similar to those used in Examples 1 and 2 were subjected to a drag test in the same manner as in Example 1 without impregnating them with a curable resin. The results are shown in Table 2.

(Comparative Example 2) Four types of base materials similar to those used in Example 1 were impregnated with varnished modified Thunol resin and heated in the same manner as in Example 2 to obtain the desired modified 4s class. A Tsunor resin reinforced base material (reinforcing material C-based cured product) was obtained.

A tensile test similar to Example 1 was conducted on these cured reinforcing material C products.

The results are shown in Table 2.

Table 1 Table 2 The base material is thin and cannot be measured Measurement conditions Base material dimensions 1101l10l1 Dragon chuck width 30mx2 Fin pulling speed 5mm/win

Claims (1)

[Claims] (1) A composite material for a printed wiring board, characterized by coating and/or impregnating a base material with a curable phosphazene compound and curing the same.