RESIN-COATED SAND FOR MULTILAYERED CASTING MOLD

摘要

Resin-coated sand for multilayered casting molds. The sand gives a multilayered casting mold improved in both consolidation strength and gas permeability. When casting is conducted with this multilayered casting mold, the sand effectively diminishes the generation of pyrolysis products (tar, soot, etc.) derived from organic substances. After casting, the casting mold can have excellent disintegrability. The resin-coated sand for multilayered casting molds comprises refractory particles whose surface has been coated with a binder composition comprising as essential components a phenolic novolak resin in which the proportion of ortho-methylene groups to para-methylene groups is 1.5 or higher and an aromatic amine. The sand has a fineness number of 80-150.