Flame-resistantly formulated, flowable, latently reactive, phenolically curable epoxy-resin moulding compounds for the encapsulation of electronic components containing the following components: an epoxy-resin component obtained from a solvent-free reaction resin mixture of polyepoxy resin and polyisocyanate resin having a molar ratio of the epoxy groups to the isocyanate groups of 1.1 to 4 at a reaction temperature of up to 220.degree. C. in the presence of a reaction accelerator in a concentration of 0.5 to 2.5% and using triphenylphosphine oxide in a concentration of 0.05 to 10%, relative in each case to the reaction resin mixture, a hardener component containing at least two phenolic hydroxyl groups per molecule, inorganic filler, and standard additives.
The present invention provides a resin composition having excellent flame retardancy without using any halogen-containing flame retardant, and prepregs and laminates using such a resin composition. More specifically, the present invention provides a flame-retardant resin composition comprising as essential components (A) an epoxy resin, (B) a curing agent and (C) a phosphorus compound containing at least as part thereof a phosphine oxide compound, a prepreg produced by impregnating this flame-retardant resin composition in a fiber base, and a laminate produced by hot-pressing a single sheet or a pile of two or more sheets of the prepreg.
The present invention provides a process for producing an epoxy resin molding material for semiconductor encapsulation, which is very low in voids generation; a molding material produced by the process; and a semiconductor device obtained by encapsulation with the molding material. That is, the present invention provides a process for producing an epoxy resin molding material for semiconductor encapsulation, which comprises premixing a composition containing at least an epoxy resin, a phenolic resin and an inorganic filler, then subjecting the resulting mixture to grinding by a grinder to obtain a powder having such a particle size distribution that the amount of particles having particle diameters of 250 .mu.m or more is 10% by weight or less, the amount of particles having particle diameters of 150 .mu.m to less than 250 .mu.m is 15% by weight or less, and the amount of particles having particle diameters of less than 150 .mu.m is 75% by weight or more, and thereafter subjecting the powder to melt kneading; a molding material produced by the process; and a semiconductor device obtained by encapsulation with the molding material.
A flame retardant phosphorus element-containing epoxy resin composition substantially free of halogen, including: (I) a non-halogenated epoxy resin material selected from: (A) a non-halogenated phosphorus element-containing epoxy resin; (B) a mixture of: (1) a non-halogenated, non-phosphorus element-containing epoxy resin, and (2) a phosphorus element-containing compound; or (C) the reaction product of: (1) a non-halogenated epoxy resin; and (2) a phosphorus element-containing compound; or (D) a combination of two or more of components (A) to (C); and (II) (A) a multi-functional phenolic crosslinking agent having a hydroxy functionality of at least 2; (B) a material which forms a multifunctional phenolic crosslinking agent having a hydroxy functionality of at least 2, upon heating or (C) a mixture of components (A) and (B); in an amount of from about 50% to about 150% of the stoichiometric amount needed to cure the epoxy resin. Electrical laminate circuit boards having reduced flammability may be made from these compositions.
