JPH02283718A - Epoxy resin composition, prepreg and laminate - Google Patents

Abstract

PURPOSE:To obtain an epoxy resin composition improved in heat resistance and being useful for the production of a laminate by mixing an epoxy resin with a polymerizable unsaturated dicyandiamide derivative. CONSTITUTION:An epoxy resin composition comprising an epoxy resin (A1) and a polymerizable unsaturated dicyandiamide derivative (A2) and desirably containing a polymerizable unsaturated resin (B1) and a polymerization initiator (B2). An example of the derivative (A2) used is one obtained by reacting a compound having an epoxy group and a polymerizable unsaturated group in the molecule with dicyandiamide in the presence or absence of a solvent at 70-140 deg.C. The mixing ratio between these components is such that 0.4-4.2 epoxys of the compound having an epoxy and a polymerizable unsaturated group in the molecule are present per active hydrogen of dicyandiamide. When the number of the epoxys is below 0.4, the solubility in a solvent is poor, while when it is above 4.2, the heat resistance of a laminate is low.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a laminate useful for printed circuit boards and the like, a prepreg thereof, and an epoxy resin composition used therefor.

(Prior art) Glass laminates used as printed circuit boards are prepared by dissolving epoxy resin and dicyandiamide in a solvent, impregnating a glass cloth with the solution, and drying it to form a B-stage to obtain a prepreg. It is manufactured by heating and press molding.

[Problems to be solved by the present invention]

In the above method for manufacturing a laminate, dicyandiamide is poorly dissolved in a solvent, so acetone (boiling point 56
．． It is necessary to use high boiling point solvents such as methyl cellosolve (boiling point 124°C) and dimethylformamide (boiling point 153°C) in addition to methyl ethyl ketone (boiling point 79.6°C) and drying to B-stage. These high boiling point solvents are not completely volatilized during the drying process and remain in the prepreg.
This has problems such as lowering the solder heat resistance of a laminate formed using this material.

[Means to solve the problem]

As a result of intensive research in view of this situation, the present inventors found that by using a polymerizable unsaturated group-containing dicyandiamide derivative as a curing agent for epoxy resin, methyl cellosolve and dimethyl It can be dissolved well without using a high boiling point solvent such as formamide, and the prepreg obtained using a resin composition in which this derivative is used in combination with an epoxy resin can significantly reduce the amount of residual solvent. The laminate does not have any residual solvent that reduces the soldering heat resistance, and furthermore, when a resin having a polymerizable unsaturated group and a polymerization initiator are used together, the laminate can be formed from prepreg. At the same time, the outflow of the resin at the initial stage of molding is suppressed, making it easier to control the thickness of the laminate, and the heat resistance (glass transition temperature) of the laminate is improved due to the synergistic effect with the above-mentioned dicyandiamide derivative containing a polymerizable unsaturated group. This is what led to the completion of the present invention.

That is, the present invention contains an epoxy resin (A') and a polymerizable unsaturated group-containing dicyandiamide derivative (A2), and more preferably a polymerizable unsaturated resin-containing resin (B+),
An epoxy resin composition containing a polymerization initiator (B2), a prepreg obtained by B-staging an impregnated base material obtained by impregnating a fibrous base material with the resin composition, and a predetermined number of sheets of the prepreg. , provides a laminate plate in which metal foil is laminated on one side or on both upper and lower sides and then heated and formed.

Next, the present invention will be explained in detail.

The epoxy resin (A+) used in the present invention is a compound having one or more, preferably two or more epoxy groups in one molecule, such as alkyl glycidyl ether, alkylphenol glycidyl ether, alkyl glycidyl ester, phenyl glycidyl ester, bisphenol. - Shrimp chlorohydrin condensate, bisphenol F-
Aromatic glycidyl ethers, aliphatic glycidyl ethers, alicyclic glycidyl ethers, aromatic glycidyl ethers such as epichlorohydrin condensates, bisphenol S-epichlorohydrin condensates, phenol novolac shrimp chlorohydrin condensates, cresol novolac shrimp chlorohydrin condensates Glycidyl ester, aliphatic glycidyl ester, alicyclic glycidyl ester, hydantoin epoxy resin,
Examples include heterocyclic glycidyl ethers, glycidyl amine compounds, cocondensates or copolymers thereof, or mixtures thereof. Further, as the polymerizable unsaturated group-containing dicyandiamide derivative (A2) used in the present invention, for example, a compound having an epoxy group and a polymerizable unsaturated group in one molecule and dicyandiamide in the presence or absence of a solvent, Examples include those obtained by reacting at ~140°C, and the blending ratio of these is dicyandiamide activated water i
The ratio is such that the compound having an epoxy group and a polymerizable unsaturated group has 0.4 to 4.2 epoxy groups, preferably 0.6 to 2.0 epoxy groups per molecule. If the number is less than 0.4, the solubility in the solvent will be poor, and if it is more than 4.2, the heat resistance of the laminate will decrease.

Examples of compounds having an epoxy group and a polymerizable unsaturated group in one molecule include glycidyl (meth)acrylate, allyl glycidyl ether, furfuryl glycidyl ether, vinylcyclohexene monoepoxide, and compounds having two epoxy groups in one molecule. Epoxy compound mono (
Examples include meth)acrylate.

The above polymerizable unsaturated group-containing dicyandiamide derivative (A
The reaction to obtain 2) is a reaction between the active hydrogen of dicyandiamide and the epoxy group in a compound having an epoxy group and a polymerizable unsaturated group in one molecule, and this can be achieved by adding a reaction accelerator such as a basic compound. The reaction is accelerated, but
Although it is thought that the unsaturated group is consumed by the Michael addition reaction with the active hydrogen of dicyandiamide at the same time as the above reaction, which is not necessarily necessary, C'NMR analysis of the obtained dicyanhydrin derivative (A2) shows that
It was found that 70% or more of the unsaturated groups at the start of the reaction remained.

The above dicyandiamide derivative obtained as in step 2 (
In A2), the active hydrogen of dicyandiamide is consumed due to the reaction between the active hydrogen of dicyandiamide and the epoxy group, but the active hydrogen still remains, and the epoxy tree Q1m)
When blended with dicyandiamide, it also functions as a curing agent, and a new polymerizable unsaturated group is added to the dicyandiamide molecule. ! It is possible to react with a compound having a Japanese group, and a resin composition made of these components is impregnated into a fibrous base material and obtained through a predetermined process.
It is estimated that the heat resistance will be improved. From this point of view, the heat resistance of a laminate obtained using a resin composition containing a high boiling point solvent is also improved compared to that using conventional dicyandiamide.

In addition, dicyandiamide cannot be dissolved only in a low-boiling point solvent such as acetone or methyl ethyl ketone, and a mixed solvent with a high-boiling point solvent such as methyl cellosolve must be used. Because of its low crystallinity, it is understood that it is soluble only in the above-mentioned low-boiling point solvent.In this way, a laminate obtained using a resin composition containing only a low-boiling point solvent has an even higher heat resistance. improves.

In the present invention, a curing accelerator, other additives, etc. can be further added to the epoxy resin (A+) and the polymerizable unsaturated group-containing dicyandiamide derivative A2), if necessary.

Typical curing accelerators include diethylamine,
Triethylamine, diisopropylamine, monoethanolamine, jetanolamine, triethanolamine, methylethanolamine, methylgetanolamine, monoisopropanolamine, nonylamine, dimethylaminopropylamine, diethylaminopropylamine, α-hensylgetanolamine ,2,4.6-
) Lisdimethylaminomethylphenol or its tri-2-ethylhexylate; 2-dimethylaminomethylphenol, pyricine, piperidine, N-aminopropylmorpholine, ■, 8-diazavinchro<5.4.0
) Various amines such as undecene-7 or its salts with phenol, 2-ethylhexanoic acid, oleic acid, diphenylphosphorous acid or organic phosphorous acids; 2-methylimidazole, 2-isoprobylimidazole, 2- Undecylimidazole, 2-phenylimidazole, 2
-phenyl-4-methylimidazole, l-hair',
; 2-methylimidazole, imidazole and Cu.

Metal salt complexes such as Ni or Go: imidazole Q such as cyanoethylation type imidazole obtained by reacting 2-methylimidazole with acrylonitrile, or an adduct thereof with trimellitic acid or a reaction product with dicyandiamide; BF3 -monoethanolamine, BF3-hensylamine, 8F3-dimethylaniline, BF3-)diethylamine, BF3-n-
Hexylamine, BF3-2,6-diethylamine, B
BF such as F3-aniline or BF3-piperidine
3-amine complexes; 1. Amine imide compounds using l-dimethylhydrazine as a starting material include phosphorus compounds such as triphenyl phosphite and organic acid metal salts such as tin octylate.

In the present invention, polymerizable unsaturated group-containing resin (hereinafter unsaturated resin)
B+)) can be used together with the components (A1) and (A2) above to suppress the flow of the impregnated resin and improve the heat resistance of the laminate when manufacturing a laminate by molding prepreg. It is preferable in that it improves properties.

The unsaturated resin (Bυ) referred to herein refers to a resin that hardens through a radical polymerization reaction of the unsaturated resin group contained therein, and representative examples include epoxy vinyl ester resin,
Examples include urethane acrylate resin, 2-polyester acrylate resin, unsaturated polyester resin, diallyl phthalate resin, spiran resin, and addition polymerization type polyimide.

Among these, epoxy vinyl ester resins and/or unsaturated polyester resins are preferred, and epoxy vinyl ester resins are particularly preferred since they are excellent in heat resistance and adhesiveness to metal foil.

The epoxy vinyl ester resin used as the unsaturated resin (B-) can be selected from the various epoxy resins described above, preferably bisphenol type or novolac type epoxy resins, each singly or in combination, and the following: Examples include resins obtained by reacting unsaturated basic acids such as the following: in the presence of an esterification catalyst. The vinyl ester resin thus obtained can be used in solvents such as polymerizable vinyl nitrates such as styrene, vinyltoluene, and (meth)acrylic acid esters, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, and esters such as cellosolve acetate. Although it may be arbitrarily melted in advance, the solvent and polymerizable vinyl monomer are usually used in a ratio of 20 to 60% by weight (total 100% by weight) with respect to 80 to 40% by weight of the vinyl ester resin.

Typical unsaturated basic acids include acrylic acid, methacrylic acid, cinnamic acid, crotonic acid, monomethyl maleate, monopropyl maleate, monobutyl maleate, sorbic acid, and mono (2-ethylhexyl) maleate. These can be used alone or in combination of two or more.

Further, a carboxyl group-containing epoxy vinyl ester resin obtained by reacting the above epoxy vinyl ester resin with a dibasic acid anhydride as described below can also be used as the epoxy vinyl ester resin in the present invention.

Typical dibasic acid anhydrides include phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, nadic anhydride, methylnadic anhydride, Among the typical examples of polybasic acid anhydrides, such as maleic anhydride, succinic anhydride, and itaconic anhydride, there are dibasic acid anhydrides. Examples include those obtained by reaction with polyhydric alcohols. The unsaturated polyester resin is prepared using the same polymerizable vinyl monomer and solvent as described above.
They may be melted in advance, and they can be optionally added alone or as a mixture of two or more, but usually 6 to 80% by weight of unsaturated polyester.
It is used in a proportion of 0 to 20% by weight (total 100% by weight).

Typical unsaturated dibasic acids include maleic acid, maleic anhydride, fumaric acid, and halogenated maleic anhydride; other typical saturated dibasic acids include: Examples of polyhydric alcohols include phthalic acid, phthalic anhydride, halogenated phthalic anhydride, isophthalic acid, terephthalic acid, tetrahydrophthalic anhydride, succinic acid, adipic acid, and sebacic acid.On the other hand, typical polyhydric alcohols include ethylene. Glycol, diethylene glycol, triethylene glycol, propylene glycol,
Dipropylene glycol, 1,3-7' ethylene glycol, l,4-butylene glycol, neopentyl glycol, hydrogenated bisphenol A, 1,6-hexanediol, adduct of bisphenol A and ethylene oxide or propylene oxide, glycerin , trimethylolpropane, etc.

In order to obtain epoxy vinyl ester resin or unsaturated polyester resin using these raw materials, conventionally known methods may be followed. It is recommended to use a polymerization inhibitor for the purpose of adjusting the storage stability or curability of the resulting resin.

Typical examples of such polymerization inhibitors include hydroquinones such as hydroquinone, p-t-butylcatechol, and mono-t-butylhydroquinone; phenols such as hydroquinone monomethyl ether and di-tp-cresol; -benzoquinone, naphthoquinone,
Quinones such as p-torquinone; or copper salts such as copper naphthenate.

In the present invention, it is also preferable to use a polymerization initiator (B), which preferably decomposes at a temperature lower than the heating and pressing temperature used to obtain the laminate, such as cyclohexanone peroxinide, 3.3 .5 trimethylcyclohexanone peroxide, methylonexa, lamperoxide, 1,1-bis(1-butylperoxy)33.
5-trimethylcyclohexane, cumene-f-droperoxide, dicumyl peroxide, lauroyl peroxide, 3.55-trimethylhexanoyl peroxide, benzoyl peroxide, di-myristyl peroxydicarbonate, t-butyl peroxide (
Organic peroxides such as t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxybenzoate, and cumylperoxyoctoate can be mentioned.

In addition, as the solvent used in the present invention, for example, only a low boiling point solvent such as acetone or methyl ethyl ketone may be used, but ketones such as methyl isobutyl ketone and cyclohexanone, esters such as cellosolve acetate and butyl acetate, dimethylform7 A zero-polymerizable vinyl monomer, which may be used by adding a small amount of Mido, etc., may be added as a diluent. In addition, even when using a large amount of a high boiling point solvent such as the above-mentioned dimethylformamide, the unsaturated resin (B1)
is cured by the crosslinking reaction by the dicyandiamide derivative, so the heat resistance of this cured resin is improved. From this point of view, the above-mentioned high boiling point solvents can also be used.

The epoxy resin composition of the present invention is the above-mentioned (AI).

It contains at least (A2), but preferably also contains components (B1) and (B2), and if necessary, additives such as a curing accelerator, an internal mold release agent, a pigment, and a filler are added. It can also be impregnated into a fibrous base material.

Note that the solid component does not necessarily need to be dissolved or melted in the liquid component during impregnation, and may be used in the form of a powder dispersed in the liquid component.

The sum of the weights of the epoxy resin (AI) contained in the epoxy resin composition of the present invention and the polymerizable unsaturated group-containing dicyandiamide (A2) as a curing agent for epoxy resin, and the weight of the unsaturated resin (B1). The ratio of ((AI) + (A2
) 8B, ) is preferably 55/45 to 98/2, but more preferably 60/40 to 9515 in terms of moldability, adhesion to metals, especially copper foil, and glabellar peel strength. The non-volatile content is the weight of the residue when 1 g of resin is placed in a round-bottomed aluminum Petri dish and heated at 150° C. for 1 hour to reduce the weight.

The filler to be added as necessary to the epoxy resin composition of the present invention is appropriately selected depending on the required performance, working conditions, etc., and examples include aluminum hydroxide, aluminum silicate, co-hydridal silica, calcium carbonate, Examples include calcium sulfate, mica, talc, titanium dioxide, quartz powder, zirconium silicate, glass powder 1, asbestos powder, diatomaceous earth, and antimony dioxide.

The blending method and blending order of each component in obtaining the epoxy resin composition of the present invention are not particularly limited;
A resin composition consisting of A1) and (A2), (B+) and (
After separately preparing the resin composition consisting of B2), they may be mixed and melted in a solvent.
) may be dissolved separately in an appropriate solvent and mixed.

The present invention provides a prepreg in which a fibrous base material is impregnated with the above-mentioned epoxy resin composition and B-staged, and a laminate using the same. fibers, carbon fibers, aromatic polyamide fibers, etc., and among them, glass fibers are preferred. Among these, glass fibers include E-glass, C-glass, A-glass, and S-glass from the viewpoint of their raw materials, but any of these types can be used in the present invention.

These fibrous base materials can be classified into roving, chipped strand mat, continuous mat, cloth, nonwoven fabric, roving cloth, surfacing cloak, and chipped strand depending on their shape, but the above types and shapes are The material may be appropriately selected depending on the intended use and performance of the molded article, and two or more types or shapes may be used in combination if necessary. Among them, cloth and nonwoven fabric are preferred.

When obtaining the prepreg and laminate of the present invention, the volume ratio of the fibrous base material is 30 to 30% of the impregnated fibrous base material after removing the solvent.
A range of 70% is appropriate.

After impregnating a fibrous base material with the epoxy resin composition of the present invention to obtain an impregnated fibrous base material, the method for removing the solvent in the impregnated base material is not particularly limited, but Usually, a method is adopted in which the solvent is volatilized while the fibers are separated one by one. At this time, the impregnated fibrous base material may be pre-cured or B-staged at the same time.

The temperature for volatilizing the solvent and pre-curing or B-staging the impregnated fibrous base material by heating is usually 70°C to 160°C,
Preferably it is 100°C to 150°C. If the temperature is lower than 70°C, it is difficult for the solvent to volatilize, and if it is higher than 160°C, it becomes difficult to obtain appropriate fluidity of the resin during the subsequent heat molding, which is not preferable.

In addition, methods for efficiently volatilizing the solvent include, for example, a method of blowing hot air onto the impregnated fibrous base material, a method of performing heating and suction or depressurization simultaneously or separately, a method of using infrared rays or far infrared rays, and a method of using high frequency heating. Examples include.

These methods may be carried out under an inert gas atmosphere, preferably nitrogen gas, and in that case, the oxygen concentration in the inert gas atmosphere is preferably 3 mol % or less.

When removing this solvent, the solvent content remaining in the impregnated fibrous base material after this removal (hereinafter referred to as the impregnated fibrous dry material) is set to 0.0% relative to the resin content in the impregnated fibrous dry material.
It is preferable to control the content to 5% by weight or less.

In the above, preliminary curing and B-staging of the impregnated fibrous base material promotes the reaction of the resin component and increases the viscosity of the resin component to the extent that it substantially loses fluidity at room temperature and under no pressure.
When heated to 140°C or higher, the reaction progresses to a state where it becomes fluid again and then hardens. Among these, B-
Staging refers to further progressing the reaction within this range until the surface of the impregnated fibrous base material is in a tack-free state without stickiness, or in a state close to this. In either case, when heated and pressurized on a flat plate at 150°C and 15 kg/-, the resin component that had been impregnated in the impregnated fibrous base material leaked out of the impregnated fibrous base material. Pre-curing or B-
Preferably, it is staged.

In order to obtain the laminate of the present invention, a plurality of sheets of the impregnated fibrous dry base material obtained as described above are superimposed if necessary, and a release film and/or metal foil is further superimposed on both sides. It can be heated and formed using the more well-known static press, continuous double belt press, etc., and the forming temperature is usually 13
The temperature is 0 to 220°C, preferably 140 to 180°C.

The molding pressure is usually contact pressure ~ 50 g/oJ, preferably 5 ~ 40 kg/-4. For example, in molding with a static press, after cutting the impregnated fibrous dry base material to a predetermined size, However, when molding is performed using a continuous belt press, the impregnated dry fibrous base material is kept in a long length and, if necessary, is continuously overlapped and laminated, and then molded using a continuous belt press. At this time, if necessary, post-curing may be further performed after taking out from the heat molding machine.

In addition, different types of impregnated fibrous dry base materials obtained by impregnating the above-mentioned fibrous base material with different types of epoxy resin compositions with different blending ratios of resin components of the epoxy resin compositions to be impregnated may be combined depending on the purpose. Alternatively, a laminate may be formed by combining the impregnated fibrous dry base material used in the present invention with a prepreg obtained by impregnating it with another resin.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

In addition, all parts and percentages in the examples are based on weight unless otherwise specified.

Reference Examples 1 to 3 [Production example of a dicyandiamide derivative (A2) containing an associative unsaturated group as a curing agent for epoxy resin] After mixing raw materials with the composition shown in Table 1, stirring at 120°C for 3 hours. to obtain a liquid product and then at 120°C.
Aspirator vacuum was applied to remove the solvent methyl celerol, and then diluted with methyl ethyl ketone.
Dicyandiamide derivative solution with a concentration of 50% (A-1,
A-2, A, 3) was obtained as a curing agent for epoxy resin. As a result of C''-NMR measurement, the epoxy groups contained in the raw materials were found to have reacted at the base.

(Margin below this page) Table 1 <Examples 1 to 5, Comparative Example 1.2> Epoxy resin compositions of Examples 1 to 5 (1-1, 1-2, 1 -3, 1-4, 1-5), epoxy resin composition of Comparative Example 112 (, 1-1', I-
2°) was obtained.

Epoxy resin compositions 1-1 to 5 used methyl ethyl ketone alone as a solvent, but were homogeneous solutions. Epoxy resin composition! -1' and I-2' were prepared by dissolving dicyandiamide in a mixed solvent of methyl cellosolve and dimethylformamide in advance.

Each of the above epoxy resin compositions was impregnated into a continuous piece of glass cloth with a width of 10,200 mm and a thickness of 0.18 mm, and heated and dried in a hot air dryer at 160°C for 3 minutes, resulting in a resin content of 42%. Flexible tank-free hoofable prepregs of Examples 1 to 5 (n-1, If-
2, n-3, n-4, If-5) and prepregs of Comparative Examples 1 and 2 (■-1°, n-2') were obtained.

Next, prepreg is extracted from this continuous prepreg roll, 8 sheets are stacked, and electrolytic copper foil with a thickness of 35μ is stacked on both the top and bottom surfaces, and the prepreg is fed into a double vent set at a temperature of 170℃, and immediately 20kg/c ! Under the pressure of
Next, cool to below 100℃, cut both ends and both edges,
The laminates of Examples 1 to 5 (■-1 to I[l-5) and the laminates of Comparative Examples 1 to 2 (Iff-1', Ill-2') having a size of 1000 m x 1000 m were obtained.

(Margins below this page) Table ~2 In the table, the specific contents of each component are as follows.

(1) Epicron 1125-75M; solid content 75%
, solvent methyl ethyl ketone, solid epoxy equivalent 68
5 (manufactured by Dainippon Ink ■) (2) Epicron N-660-75 month; solid content 75%,
Solvent methyl ethyl ketone, solid content epoxy equivalent 195
(Manufactured by Dainippon Ink ■) (3) Deipkrite [IE-7016-72M,
Solid content 72%, solvent methyl ethyl ketone, raw material brominated epoxy resin epoxy 1370 (manufactured by Dainippon Ink) (4) Polylite FG-387 (Dainippon Ink tll!J) by replacing the styrene component with methyl ethyl ketone, making the resin solid 72%.

The resulting laminate was post-cured at 170° C. for 60 minutes.

The resin flow rate during molding, the solder heat resistance of the laminate, and the Tg were measured as follows. The results are shown in Table 3.

Resin flow rate during molding Percentage calculated by dividing the weight of the resin protruding from the 10201 m width of Nigarasu cloth by the weight of the product excluding the 1020 m wide copper foil.

Solder heat resistance: Remove the copper foil on one side of a 25x50mm laminate by etching, absorb water in a pre-7 shaker under the conditions of 120℃, 2 atm, and 4 hours, then wipe off the moisture on the surface. The sample was immersed in a solder bath at 280° C. for 2 minutes, and the state of blistering of the copper foil and the state of peeling of the inner layer of the sample were visually determined.

◎: No change.

×: Copper foil blisters and/or inner layer plagiarized.

Tg: Measured using a dynamic solid viscoelasticity measuring device, RS^-■ manufactured by Rheometric Co., Ltd., by increasing the temperature at l'lc/sin.

As is clear from the above results in Table 3, the epoxy resin compositions of Examples of the present invention were able to cure methyl ethyl ketone by using the polymerizable unsaturated group-containing dicyandiamide derivative solutions (A-1 to ^-3) as curing agents. A uniform epoxy resin composition can be obtained using a single solvent, and the resulting laminate has excellent solder resistance. When the curing agent is used in a combined system of an epoxy resin and a resin having an unsaturated group as in Examples 2 to 4,
Tg is particularly improved.

〔Effect of the invention〕

According to the present invention, since the polymerizable unsaturated group-containing dicyandiamide derivative is used in combination with the epoxy resin, the polymerizable unsaturated group-containing dicyandiamide derivative dissolves even in low-boiling point solvents in which dicyandiamide cannot be dissolved.
Each of these components can be dissolved in a low boiling point solvent, thereby reducing the amount of solvent remaining in the prepreg and its laminate, and improving the heat resistance of the laminate. Moreover, by further using an unsaturated resin in combination, it is possible to suppress excessive outflow of the resin during laminated sheet molding, and to further improve the heat resistance of the laminated sheet.

April 25, 1999

Claims (5)

[Claims] (1) An epoxy resin composition containing an epoxy resin (A_1) and a polymerizable unsaturated group-containing dicyandiamide derivative (A_2). (2) The epoxy resin composition according to claim 1, comprising a polymerizable unsaturated group-containing resin (B_1) and a polymerization initiator (B_2). (3) Polymerizable unsaturated group-containing dicyandiamide derivative (A
The epoxy resin composition according to claim 1 or 2, wherein _2) is a compound obtained by reacting glycidyl (meth)acrylate and/or allyl glycidyl ether with dicyandiamide. (4) A prepreg characterized in that an impregnated fibrous base material obtained by impregnating a fibrous base material with the epoxy resin composition according to any one of claims 1 to 3 is B-staged. (5) stacking a predetermined number of prepregs according to claim 4;
A laminate plate characterized by laminating metal foils on one side or both top and bottom sides and heat forming them.