NOVOLAC-TYPE PHENOL RESIN, RESIN-COATED SAND FOR SHELL MOLD, AND TEMPLATE

摘要

PROBLEM TO BE SOLVED: To provide a novolac-type phenol resin giving little generation of heat degradation products derived from a binder and produced during molding without reducing template characteristics and improved in stickiness of the heat degradation product when the resin is used as the binder of RCS for shell mold. SOLUTION: The novolac-type phenol resin contains≤10% sum content of the monomer and the dimer of phenol measured by gel chromatography area and has≤3.0 dispersion rate (Mw/Mn) of weight average molecular weight (Mw) over number average molecular weight (Mn) and≤0.95 ratio of ortho bondings/para bondings of methylene groups. COPYRIGHT: (C)2006,JPO&NCIPI