NOVOLAC TYPE PHENOLIC RESIN FOR SHELL MOLD AND RESIN- COATED SAND

摘要

PROBLEM TO BE SOLVED: To provide a novolac type phenolic resin for a shell mold which enables a mold of a low coefficient of thermal expansion to be obtained, and resin-coated sand produced by mixing the novolac type phenolic resin for the shell mold with fire-proof aggregate.;SOLUTION: The novolac type phenolic resin for the shell mold is composed of an alkylbenzene-modified novolac type phenolic resin of which the ratio of modification by alkylbenzene is 3-70 wt.% and the number-average molecular weight is 300-1,000.;COPYRIGHT: (C)2003,JPO