Abstract: A resin composition comprising a polymeleimide compound having two or more maleimide groups in one molecule, a phenol novolac resin of which phenolic hydroxyl groups are epoxidized and allyl-etherified and, as an optional ingredient, a curing agent, or a resin composition comprising a polymaleimide compound having two or more maleimide groups in one molecule, a phenol novolac resin of which phenolic hydroxyl groups are allyl-etherified and an epoxy resin; and a heat resistant composite material comprising cured product of said resin composition as its matrix phase and containing a fiber as its reinforcing material.

Abstract: An abrasive brush comprising at least one stick consisting of long inorganic fibers each having a diameter of 3 .mu.m to 30 .mu.m which are aligned and bonded with a resin, and said stick having a cross sectional area of 0.002 mm.sup.2 to 2.5 mm.sup.2, which can abrase a curved or intricate surface of a material to be abrased and has a large abrasion ability, large mechanical strength and consumption resistance.

Abstract: A resin composition comprising a polymeleimide compound having two or more maleimide groups in one molecule, a phenol novolac resin of which phenolic hydroxyl groups are epoxidized and allyl-etherified and, as an optional ingredient, a curing agent, or a resin composition comprising a polymaleimide compound having two or more maleimide groups in one molecule, a phenol novolac resin of which phenolic hydroxyl groups are allyl-etherified and an epoxy resin; and a heat resistant composite material comprising cured product of said resin composition as its matrix phase and containing a fiber as its reinforcing material.

Abstract: A new process for producing an inorganic fiber of superior tensile strength and modulus of elasticity, which comprises spinning a spinning solution in organic solvent of polymetaloxane of good spinnability to form a precursor fiber, calcining said precursor fiber, and wherein said solution contains polymetaloxane comprising 0.1-95 mole % of a structural unit represented by the following general formula [A] and 99.9-5 mole % of the following formula [B]: ##STR1## (wherein, M represents a trivalent or tetravalent metal atom, X.sub.1 represents an organic group which is the same as or different from ##STR2## hydrogen, nitro or halogen, X.sub.2 and X.sub.3 represent an organic group other than ##STR3## Y represents an organic group, nitro or halogen, m represents an integer from 1 to 3.).