PURPOSE: To improve strength and water absorption properties by a method wherein additives comprising a specified phenolic compd., etc., are mixed with inert particles and are pressed to form a molded body and during pressing, under action of heat, the phenolic resin is completely cross-linked.
CONSTITUTION: A binder comprising bisphenol solid particles and at least one compd. emitting formaldehyde and a catalyst, i.e., a substance accelerating curing and crosslinking by catalytic action and optionally further additives customarily employed in preparing phenolic resins are mixed together. In addition, after the mixture obtd. is precompressed and preformed, it is compressed into a molded body and during compressing, under the action of heat, bisphenol and formaldehyde are completely cured and crosslinked to form a phenolic resin which is non-water-soluble and non-fusible any more. It is possible thereby to improve strength and water absorption properties.
GERUTO BEE SHIYUUREN
RUISU GEE EMU DORIISEN
