| 摘要 |
PURPOSE:To obtain molding sand having a low moisture content by adding and mixing a water soluble powder saccharide to and with silica sand then adding and kneading an aq. soln. contg. a crosslinking agent and a catalyst for reaction to and with the mixture composed thereof. CONSTITUTION:0.1-5wt% water soluble powder saccharide is added and mixed to and with 100pts.wt. silica sand. An aq. soln. of 0.001-0.3pts.wt. cross linking agent selected from methylol converted matter of urea or melamine or alkylated methylol compd. of melamine and an aq. soln. of 0.0001-0.15pts.wt. catalyst for reaction selected from an org. acid, inorg. acid or metallic salt, ammonium salt and alkanol amine salt thereof are added and kneaded to and with the mixture thereof to prepare molding sand. Soluble starch, dextrin, cane sugar, maltose, glucose, etc. are used for the water soluble saccharide. |
