Sand mold composition for metal casting

摘要

A sand mold composition for the metal casting comprising a molding sand and pullulan as a binder therefor. As compared with prior art, the present composition has following advantages: in the molding step, no gas, dust, noise, or vibration is generated; in the pouring and sand stripping steps, neither noxious gas nor offensive odor is emitted; although the mold has a sufficiently high strength at room temperature for the convenient handling, it is readily broken down after the casting and so renders the knock-out and sand stripping very easy; and the recovered sand can be reused as such, practically without any after-treatment. The molding cycle is comparable to that of conventional oil sand or carbon dioxide-bonded mold.