PURPOSE: To produce molds of excellent resisting pressure not giving offensive smell, by using coated sand for casting having high molecular compound layer possessing carboxylic group, etc., in the molecules, provided on the surface of sand and with powder of metal oxide, etc., deposited thereon.
CONSTITUTION: A layer of high molecular compound possessing carboxylic group or carboxylic anhydride group in the molecules of copolymerization of one kind or more than two kinds of maleic acid, etc., is provided on the surface of sand, and powder of compound of at least one kind selected from oxides and carbides of metals such as MgO, and MgCO3, is deposited thereon to prepare coated sand for casting. A sand mold using this coated sand for casting is used as the core to fabricate a mold. In this method, the high molecular compound melted by metal oxides, etc., is hardened, and a mold having an excellent resisting pressure may be obtained. Also when casting, release of offensive smell from phenol resin in the conventional method may be prevented.
SATOU SHIYUUJI
SUGAMURA TADAHIRO
KUSAKA SHIGERU
KASHIMA JIROU