JPH11209582A - Epoxy resin composition for laminate, and prepreg and laminate using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition used for laminates, capable of being sufficiently cured even in a short lamination time, having excellent storage stability, moldability and rapid curability and useful for printed circuit boards, etc., by compounding an epoxy resin, a polyamine and a specific organic phosphorane as essential components. SOLUTION: This epoxy resin composition comprises (A) an epoxy resin such as a bisphenol A type epoxy resin, (B) a polyamine such as 4,4'- diaminodiphenylmethane, and (C) an organic phosphorane of formula I (R<1> -R<3> are each an organic group having an aromatic ring or a heterocyclic ring or a monovalent aliphatic group; R<4> and R<5> are each an organic group having an aromatic ring or a heterocyclic ring or a monovalent aliphatic group), such as a compound of formula II preferably in an amount of 0.01-10 pts.wt. (per 100 pts.wt. of the component A) as essential components. It is preferable to produce a prepreg or a laminate from the composition and a substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an epoxy resin composition for a laminate which can be rapidly cured. More specifically, printed wiring, which can be quickly cured when heated at the time of molding to give a molded product of good moldability and high quality and can be stably stored at about room temperature for a long period of time. The present invention relates to a resin composition useful for a board, and a prepreg and a laminate using the same.

[0002]

2. Description of the Related Art In recent years, in order to automate processing equipment, save energy, and further improve productivity, epoxy resin multilayer printed wiring boards have been required to exhibit desired performance by heat molding in a short time. I have. By adding a large amount of catalyst to the varnish, heat molding in a short time can be made possible.However, although the curability during heat molding is improved, the melt viscosity during molding is significantly increased, resulting in a circuit pattern. It is difficult to control in terms of moldability such as resin embedding. Further, by increasing the amount of the catalyst, the curing reaction of the resin proceeds during storage at around room temperature, and the characteristics are reduced. Thus, it has been difficult to achieve both fast curing at high temperatures, moldability, and room temperature storage stability.

[0003]

SUMMARY OF THE INVENTION The present invention has been made as a result of intensive studies to solve such problems of the epoxy resin composition for a laminated board. An epoxy resin composition for a laminated board, and a prepreg and a laminated board using the same, which give a high-quality molded article, have good moldability, and can be stably stored at around normal temperature for a long period of time. The purpose is to provide.

[0004]

That is, the present invention comprises, as essential components, an epoxy resin (A), a polyamine (B), and an organic phosphorane (C) having a curing promoting effect and represented by the general formula [1]. It is an epoxy resin composition for laminated boards. Furthermore, a prepreg and a laminate using the resin composition.

[0005]

Embedded image In the formula, R ^{1 to} R ³ are an organic group having an aromatic ring or a heterocyclic ring, or a monovalent aliphatic group, and each of the substituents forms a PC bond with a phosphorus atom. They may be the same or different. Also, R ⁴ and R ⁵
Represents an organic group having an aromatic ring or a heterocyclic ring, or a monovalent aliphatic group, which may be the same or different.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, in order to shorten the time required for heat molding an epoxy resin laminate, a catalyst having a curing promoting effect is generally added, but the curing speed is improved. In addition, the melt viscosity at the time of molding increases remarkably, and it is difficult to control the moldability such as the ability to embed the resin into the circuit pattern. In addition, the curing reaction of the resin proceeds during storage at around room temperature, and the resin composition or prepreg cannot be stored at room temperature for a long period of time.

In the present invention, in order to solve such a problem, as a result of intensive studies on a catalyst having a curing promoting effect, an organic phosphorane (C) represented by the general formula [1] is obtained.
By using, it has become possible to achieve both a reduction in the time for heat molding and a long-term storage of the resin composition and the prepreg. Especially,
In the B stage state, which is the use state of the prepreg,
The technology is based on a latent catalyst that satisfies curability, moldability and storage stability at the same time, with a high curing speed leading to final curing at the molding temperature without sacrificing moldability and room temperature storage stability. It is.

As the epoxy resin (A) used in the present invention, any epoxy resin having two or more epoxy groups, which has been conventionally used for electric insulation, can be used. Examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolak type epoxy resin, isocyanurate type epoxy resin, glycidylamine type epoxy resin, epoxy resin having a biphenyl skeleton, epoxy resin having a naphthalene skeleton, Epoxy resin with dicyclopentadiene skeleton, epoxy resin with limonene skeleton, or trifunctional or tetrafunctional glycidylamine type epoxy resin, polyglycidyl ester of polycarboxylic acid, polyglycidyl ester of aliphatic polyhydroxy compound, etc. Polyfunctional epoxy resin, silicone-modified epoxy resin, rubber-modified epoxy resin, and the like. Furthermore, in order to provide flame retardancy,
Flame-retardant epoxy resin obtained by halogenating the above-mentioned epoxy resin, or the above-mentioned epoxy resin and tetrabromobisphenol A, a co-condensate of bisphenol A, a mixture of the above-mentioned epoxy resin with tetrabromobisphenol A and bisphenol A, A blend of the above-described epoxy resin with diglycidyl ether tetrabromobisphenol A can also be used.

The polyamine (B) acts as a curing agent for the epoxy resin. Specifically, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, metaphenylenediamine, 4'-diamino-3,3 '
-Didiethyl-5,5'-di4,4'-didimethyldiphenylmethane, 3,3'-didimethoxy-4,4'-didiaminodiphenyl,
3,3'-didimethyl-4,4'-di-4,4'-didiaminodiphenyl, 2,2'-didichloro-4,4'-didiamino-5,5'-didimethoxydimethyl, 2,2 ' , 5,5'-tetrachloro-4,4'-didiaminodiphenyl, 4,4'-dimethylenebis (2-chloroaniline), 2,2 ', 3,3'-tetrachloro-4,4'-didi Aminodiphenylmethane, 4,4'-didiaminodiphenyl ether,
4,4'-didiaminobenzanilide, 3,3'-didihydroxy
-4,4'-didiaminobiphenyl, 9,9'-dibis (4-aminophenyl) fluorene, 9,9'-dibis (4-aminophenyl) anthracene, ethylenediamine, diethylaminopropylamine, hexamethylenediamine, isophoronediamine , Bis (4-amino-3-methylcyclohexyl)
Methane and the like are exemplified.

When a guanidine derivative is used in combination as a polyamine, it is effective in improving characteristics such as storage stability and curability. Examples of such guanidine derivatives include:
Dicyandiamide, dicyandiamide aniline adduct, dicyandiamide aromatic amine adduct, 1-ortho tolyl diguanide, α-2,5-dimethyl guanide, α, ω-diphenyl diguanidide, α, α'-bisguanyl guanidino diphenyl ether , P-chlorophenyldiguanide, α, α'-hexamethylenebis [ω- (p-chlorophenol)] diguanide, phenyldiguanide oxale
And mono- or disubstituted alkyl-modified phenyldiguanide, acetylguanidine, diethylcyanoacetylguanidine and the like.

The organophosphorane (C) serving as a latent curing promoting catalyst is represented by the above general formula [1]. In the formula, R ^{1 to} R ³ are an organic group having an aromatic ring or a heterocyclic ring,
Or it is a monovalent aliphatic group, and the phosphorus atom and each substituent form a PC bond, which may be the same or different. Such groups include:
For example, methyl group, ethyl group, butyl group, allyl group, phenyl group, tolyl group, benzyl group, ethylphenyl group,
Phenoxy group, naphthyl group and the like can be mentioned.

In the general formula [1], R ⁴ and R ⁵
Is an organic group having an aromatic ring or a heterocyclic ring, or a monovalent aliphatic group, which may be the same or different. Specific examples of such a substituent include a butyl group, an allyl group, a phenyl group, a tolyl group, a benzyl group, a cyclohexyl group, an ethylphenyl group, a phenoxy group, and a naphthyl group.

It is more preferable that at least one of R ⁴ and R ⁵ has a structure in which a carbonyl group is contained in the molecule and the carbonyl group is directly bonded to a C ¹ carbon atom. It is effective for compatibility with storage stability. Examples of such substituents include acetyl, methoxycarbonyl, ethoxycarbonyl, phenoxycarbonyl, benzoyl, nitrobenzoyl, chlorobenzoyl, bromobenzoyl, salicyloyl, and naphthyl. it can.

Further, at least one of R ⁴ and R ⁵ contains a carbonyl group in the molecule, and the carbonyl group is C ^1.
It is more preferable that it has a structure directly bonded to a carbon atom, and at least one of them is an organic group having 6 or more carbon atoms, which is more effective for satisfying both fast curing property and storage stability. Examples of such substituents include tolyl, methoxyphenyl, methoxycarbonylphenyl, benzoyl, toluoyl, anisoyl, nitrobenzoyl, chlorobenzoyl, bromobenzoyl, salicyloyl, naphthyl, naphthoyl And the like.

It is also effective for storage stability that R ⁴ and R ⁵ are substituents forming a cyclic structure via the C ¹ carbon atom. Specific examples of such a cyclic structure include, for example, a cycloalkane structure, a cycloalkene structure, and a fluorene structure.

The organic phosphorane (C) in the present invention is
Acts as a curing accelerator for epoxy resins and suppresses catalytic activity at room temperature, but rapidly develops catalytic activity at high temperatures during molding, enabling both room temperature storage and rapid curing of epoxy resin compositions Becomes In addition, to organic phosphorane,
Conventionally used as a curing accelerator for epoxy resin laminates, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2
It is also possible to use commonly used curing accelerators such as imidazoles such as -methylimidazole / isocyanuric acid adduct and 2-methylimidazole / trimellitic acid adduct. By changing the amount added to the epoxy resin composition in combination with imidazoles, the curing rate of the resin composition can be easily adjusted, which is advantageous in terms of moldability. In addition, it is of course possible to use a curing accelerator known to those skilled in the art in combination.

The amount of the organic phosphorane (C) to be added to the epoxy resin is 100 parts by weight of the epoxy resin.
It is preferably 0.01 to 10 parts by weight. If the amount is more than 10 parts by weight, the viscosity rise during molding becomes faster, and the moldability decreases. Further, the preservability of the varnish obtained by dissolving the resin composition in a solvent is also reduced, and it is difficult to achieve both rapid curability, moldability and varnish preservability. Further, the influence of the deterioration of the physical properties with the increase of the addition amount cannot be ignored. On the other hand, if the amount of the organic phosphorane is less than 0.01 part by weight, satisfactory quick-curing properties cannot be obtained.

In order to prepare a prepreg or laminate by applying an epoxy resin composition to a substrate, it is common to dissolve the resin composition in a reactive diluent or solvent and use it as a varnish. . As the reactive diluent, n
-Butyl glycidyl ether, allyl glycidyl ether, styrene oxide, phenyl glycidyl ether, glycidyl methacrylate, diglycidyl ether, diglycidyl aniline, trimethylolpropane triglycidyl ether, glycerin triglycidyl ether and the like can be used. Examples of the solvent include acetone, methyl ethyl ketin, toluene, xylene, ethylene glycol monoethyl ether and its acetate compound, propylene glycol monoethyl ether and its acetate, dimethylformamide, methanol, ethanol and the like.

Depending on the method of application, an inorganic filler may be added in order to impart thixotropy. For example, aluminum oxide, hydrated silica alumina, antimony oxide, barium titanate, colloidal silica, calcium carbonate, calcium sulfate, mica, silica, silicon carbide, talc, titanium oxide, quartz, zirconium oxide, zirconium silicate, boron nitride, carbon nitride And fine particle powders such as graphite.

Further, a coupling agent can be added for improving the adhesion to a metal foil such as copper or the like and the inorganic filler. As the coupling agent, a silane coupling agent, a titanate-based coupling agent, an aluminum chelate-based coupling agent, and the like can be used.
Chloropropyltrimethoxysilane, vinyltrichlorosilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, N-β
-(Aminoethyl) -γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, isopropyl triisostearoyl titanate, isopropyl trimethacryl titanate, isopropyl tri (dioctyl phyllophosphate) titanate, isopropyl isostearoyl di (4- Aminobenzoyl) titanate and the like.

[0021]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention.

(Examples 1 to 5 and Comparative Examples 1 to 5) Multilayer printed wiring boards were prepared and, for property evaluation, moldability during heat molding, glass transition temperature of resin of the obtained laminated board, moisture absorption The solder heat resistance and the storage stability of the prepreg were evaluated. Each evaluation method was as follows.

1. Glass transition temperature Only the cured prepreg layer is cut from the multilayer printed wiring board after heat molding, and an automatic viscoelasticity measuring device RHEOV
IBRON DDV-3-EP (Orientec Co., Ltd.)
Was measured in a tensile mode at a frequency of 11 Hz and a temperature rising rate of 5 ° C./min. Tan in dynamic viscoelastic curves
The δ peak temperature was taken as the glass transition temperature.

2. Moldability After removing the outer layer copper foil of the multilayer printed wiring board after the heat molding by etching, the embedding property of the resin into the inner layer circuit pattern visible from the exposed cured prepreg layer was comparatively evaluated.

3. Moisture Absorption Solder Heat Resistance The obtained multilayer printed circuit board is subjected to PCT (pressure cooker test) moisture absorption treatment at 125 ° C., 2.3 atm and 1 hour, and is further floated in a 260 ° C. solder bath for 2 minutes. The presence or absence of swelling at the time was observed.

4. Preservability of Prepreg Prepreg immediately after coating and drying is stored at 40 ° C for 7 days,
The fluidity after storage was comparatively evaluated.

(Examples 1 to 5) First, the base material thickness was 0.18 m
The glass-epoxy double-sided copper-clad laminate with a thickness of 35 μm and a copper foil thickness of 35 μm was polished and soft-etched to remove the rust-proofing film, and then a circuit was formed by etching. This was subjected to an oxidation treatment generally called black treatment to roughen the circuit surface to prepare an inner circuit board. Next, an epoxy resin composition varnish was prepared by blending each component at a composition ratio as shown in Table 1, and this was impregnated into a glass cloth having a thickness of 180 μm by a conventional method, and dried to obtain a prepreg. Was. The chemical structural formulas of the five types of curing accelerators (organic phosphoranes) used in Examples 1 to 5 are shown in Formulas [2] to [6].

This prepreg is superimposed one by one on both sides of the inner circuit board, and furthermore, a thickness of 1
8 μm copper foils were stacked one by one and heat-formed by a vacuum press to obtain a multilayer printed wiring board. The heat molding was started from room temperature, and the material was heated at a rate of 8 ° C./min. The maximum temperature of the material was 170 ° C., and the time required for molding including heating and cooling was 60 minutes. The moldability at this time, the glass transition temperature of the resin of the obtained laminate, the moisture absorption solder heat resistance,
Table 1 summarizes the evaluation results of the storage stability of the prepreg.

[0029]

[Table 1]

(Comparative Examples 1 to 5) First, an inner layer circuit board having a roughened circuit surface was prepared in the same manner as in the example. next,
Each component was blended at a composition ratio as shown in Table 2 to prepare an epoxy resin composition varnish, which was impregnated and dried in the same manner as in the example to obtain a prepreg of a comparative example. Further, a multilayer printed wiring board was prepared in the same manner as in the examples, and the characteristics were evaluated. The evaluation results are summarized in Table 2.

[0031]

[Table 2]

[0032]

Embedded image

[0033]

Embedded image

[0034]

Embedded image

[0035]

Embedded image

[0036]

Embedded image

The glass transition temperature of the resin after curing in each of the examples was 150 ° C. or higher, which was higher than that of the comparative example. In addition, moldability, heat resistance to moisture absorption solder, 4
The fluidity of the prepreg after storage at 0 ° C. for 7 days was all good. On the other hand, the glass transition temperature of the comparative example was lower than that of the example in general, and the comparative examples 1, 2, 5
Although the sample had good moisture absorption solder heat resistance, resin filling failure occurred in the inner layer circuit pattern during molding, and voids were generated. On the other hand, in Comparative Examples 3 and 4, the moldability was good, but swelling occurred in the moisture absorption solder test. The fluidity of the prepreg after storage at 40 ° C. for 7 days was significantly reduced, and Comparative Examples 1 to 5 were not all satisfactory.

[0038]

The epoxy resin composition for laminates of the present invention has excellent curability, can be sufficiently cured even in a short lamination molding time, has excellent storage stability at room temperature, and further has excellent moldability. Alternatively, it can be suitably used for manufacturing printed wiring. In particular, because it has excellent fast-curing properties,
The time required for heat molding, which used to take 150 minutes or more in a single press, can be reduced to about 60 minutes, which significantly reduces manufacturing costs and man-hours spent on quality control and inventory control. Become like Also, moldability,
The preservability and other physical properties of the varnish can maintain the conventional quality, and are extremely effective for satisfying both the fast curing property at high temperature, the moldability, and the preservability of the varnish at room temperature.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akiko Okubo 2-58-8 Higashishinagawa, Shinagawa-ku, Tokyo Sumitomo Bakelite Co., Ltd. (72) Inventor Minoru Kobayashi 2-5-2-8 Higashishinagawa, Shinagawa-ku, Tokyo Sumitomo Bakelite Co., Ltd.

Claims (6)

[Claims] 1. An epoxy resin composition for a laminate comprising an epoxy resin (A), a polyamine (B), and an organic phosphorane (C) represented by the general formula [1] as essential components. Embedded image In the formula, R ^{1 to} R ³ are an organic group having an aromatic ring or a heterocyclic ring, or a monovalent aliphatic group, and each of the substituents forms a PC bond with a phosphorus atom. They may be the same or different. Also, R ⁴ and R ⁵
Represents an organic group having an aromatic ring or a heterocyclic ring, or a monovalent aliphatic group, which may be the same or different. 2. The organic phosphorane (C) represented by the general formula [1], wherein at least one of the substituents R ⁴ and R ⁵ has a carbonyl group in the molecule, and the carbonyl group has a C ¹ carbon atom. The epoxy resin composition for a laminate according to claim 1, wherein the epoxy resin composition has a directly bonded structure. 3. The organic phosphorane (C) represented by the general formula [1], wherein at least one of the substituents R ⁴ and R ⁵ is an organic group having 6 or more carbon atoms. 2
The epoxy resin composition for a laminate according to the above. 4. The organic phosphorane (C) represented by the general formula [1], wherein the substituents R ⁴ and R ⁵ are organic groups forming a cyclic structure via a C ¹ carbon atom. Do
The epoxy resin composition for a laminate according to claim 1. 5. A prepreg, which is basically composed of the epoxy resin composition for a laminate according to any one of claims 1 to 4 and a substrate. 6. A laminate, which is basically composed of the epoxy resin composition for a laminate according to any one of claims 1 to 4 and a substrate.