METHOD OF DRYING AQUEOUS MOLD COATING MATERIAL FOR CASTING AND METHOD OF STICKING CALCIUM OXIDE ON SURFACE OF MOLD COATING MATERIAL

摘要

PURPOSE:To cure a water soluble mold coating material contg. colloidal silica as a binder in a short period of time and to uniformly stick calcium oxide thereto by coating the above-mentioned mold coating material to the surface of a casting mold, then sticking the calcium oxide thereto. CONSTITUTION:The water soluble mold coating material prepd. by using the colloidal silica as the binder is coated on the surface of the expendable casting mold or the ceramics shell mold. The calcium oxide is stuck to the surface of such mold coating material. Then, a chemical reaction takes place rapidly on the surface of the mold coating material and the surface thereof hardens in a short period of time. The above-mentioned water-soluble mold coating material is coated on the surface of the expendable casting mold and further the powder mold coating material is coated thereto; thereafter, the calcium oxide is stuck thereto. The excessive sticking of the calcium oxide and the exfoliation of from polyptyrene the casting mold in the drying process arising therefrom are thereby prevented.