Abstract: An epoxy resin composition used for semiconductor encapsulating, laminated boards or electrical insulation is prepared from a thermosetting resin composition containing: (A) an epoxy resin and (B) a phenol resin represented by the following general formula (1): wherein R1 and R2 are a hydrogen atom or alkyl group having 1 to 4 carbon atoms, and R3 is an amino group, alkyl group having 1 to 4 carbon atoms, phenyl group, vinyl group or the like, and wherein m is an integer of 1 or 2.

Abstract: A high molecular weight epoxy resin obtained by polymerization reaction of a difunctional epoxy resin (X) with a dihydric phenol compound (Y) containing 70-100% by weight of bisphenol S in the presence of a catalyst, the high molecular weight epoxy resin being characterized in that a weight average molecular weight thereof is 10,000-200,000. A resinous composition for a printed circuit board, comprising the high molecular weight epoxy resin, an epoxy resin other than the above-mentioned resin and a curing agent as essential components.

Abstract: The object was to provide an epoxy resin composition which has excellent flame retardancy, heat resistance and humidity resistance and is advantageously used for semiconductor encapsulating, laminated boards, electrical insulation and the like.

Abstract: An epoxy compound formula (1), and a hydrogenation process for preparing thereof; wherein R1 to R4 each represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; n represents an integer of 0 to 6; and Z1 and Z2 each represent a phenyl group substituted or unsubstituted by one or more alkyl groups or a cyclohexyl group substituted or unsubstituted by one or more alkyl groups.

Abstract: An epoxy resin which is useful as adhesives, resins for coatings, encapsulants, resins for a lamination board, casting materials, molding compounds, and electric insulators, and which can provide a cured resin having excellent heat resistance and moisture resistance is provided which comprises (A) an epoxy resin containing a trisepoxy compound represented by general formula (I), and (B) a curing agent for an epoxy resin, ##STR1## wherein R.sub.1 is a methyl group, n is an integer of 0 to 2, and Ar is a group selected from general formula (II) ##STR2## wherein R.sub.2 and R.sub.3 are an alkyl group having a carbon number of 1 to 6, an alkoxy group having a carbon number of 1 to 6, or a halogen atom, and m and p are an integer of 0 to 2.

Abstract: To provide an epoxy resin composition which can provide a cured resin which is excellent in weatherability and electric properties, and which is useful as a resin for coatings, an encapsulant, a casting material, an electric insulator, etc. An epoxy resin composition which contains a hydrogenated epoxy resin obtained by hydrogenation of an aromatic epoxy resin, wherein the hydrogenated epoxy resin has a hydrogenation ratio in an aromatic ring of not less than 85%, a loss ratio of epoxy groups of not more than 20%, and a total chlorine content of not more than 0.3% by weight.

Abstract: A polyphenol composition is provided comprising trisphenol represented by the following formula (I): ##STR1## wherein R is a methyl group, X is independently an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms or a halogen atom, and m and n are an integer of 0 to 2 which has an excellent balance between heat resistance and water resistance as a curing agent for epoxy resins.

Abstract: The epoxy resin composition which comprises both components (A) an epoxy compound having at least two epoxy groups in a molecule and (B) a polyphenol compound containing a trisphenol compound represented by general formula (I) described below ##STR1## in which R.sub.1 is a methyl group, n is an integer of 0 to 2, and Ar is a group selected from ##STR2## in which R.sub.2 and R.sub.3 are each individually selected from an alkyl group having a carbon number of 1 to 6, an alkoxy group having a carbon number of 1 to 6, or a halogen atom, and m and p are an integer of 0 to 2.

Abstract: A polyepoxy composition comprising a trisepoxide represented by general formula (I) described below which is well-balanced between thermal stability and water resistance is provided. ##STR1## In the formula, R represents a methyl group, X represents an alkyl group having a carbon number of 1 to 6, an alkoxy group having a carbon number of 1 to 6, or a halogen atom, which may be identical or different, respectively, Y represents a hydrogen atom or a methyl group, and m and n represent an integer of 0 to 2.

Abstract: A process for preparing an adduct of imidazole-isocyanuric acid which comprises an addition reaction in which a homogeneous aqueous solution of an imidazole compound represented by general formula (I) described below; ##STR1## wherein R.sub.1 represents a hydrogen atom, .beta.-cyanoethyl group, benzyl group, or .beta.-{3,5-diamino-S-triazinyl-(1)}-ethyl group, R.sub.2 represents an alkyl group having a carbon number of 1 to 20 or a phenyl group, R.sub.3 represents a hydrogen atom or a methyl group is added to a homogeneous aqueous solution of isocyanuric acid which is heated to at least 70.degree. C.

Abstract: A non-crystalline ether-imide type high purity bismaleimide composition represented by formula (I): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 each represent a hydrogen atom, a halogen atom, or an alkyl group having from 1 to 4 carbon atoms; R.sup.5 represents a hydrogen atom or a methyl group; and R.sup.6 represents a hydrogen atom, a methyl group or a phenyl group. The non-crystalline bismaleimide (I) has a purity of 95 wt % or higher, a melting point of not higher than 130.degree. C., and exhibits excellent solubility in a solvent.

Abstract: A process for producing a polymaleimide which comprises reacting an aromatic dialdehyde with 2 to 60 moles, per mole of the aromatic dialdehyde, of aromatic amine represented by the formula (I): ##STR1## wherein X is a hydrogen atom, a halogen atom or an alkyl or alkoxy group each having 1 to 4 carbon atoms to obtain a polyamine, reacting the polyamine with maleic anhydride to obtain a polyamide acid, and dehydration-cyclizing the polyamide acid to obtain a polymaleimide.