COATED SAND, MANUFACTURING METHOD FOR SAME, AND MANUFACTURING METHOD FOR MOLD

摘要

The purpose of the present invention is to provide a dry state coated sand having superior normal temperature fluidity, an advantageous method for manufacturing the same, and a method for manufacturing a mold with superior characteristics using that coated sand. The dry state coated sand having normal temperature fluidity is formed by mixing a refractory aggregate that has been heated with an aqueous water glass solution as a caking additive and evaporating the water to form a coating layer of the caking additive on the surface of the refractory aggregate. The moisture percentage thereof is adjusted to 0.5% by mass or less. After this dry state coated sand is filled into a molding cavity of a forming die, solidification or curing of this coated sand is carried out by ventilating with water vapor and a targeted mold is obtained.