| 摘要 |
PURPOSE:To provide a binder for molding sand having good warm strength and collapsing property by adding a specific amt. of magnesium hydroxide to a thermosetting resin. CONSTITUTION:A binder for molding sand is prepd. by adding 1-35pts.wt. magnesium hydroxide to 100pts.wt. thermosetting resin. A phenolic resin, melamine resin, epoxy resin, etc. are used for the thermosetting resin and the softening point thereof is preferably about 50-130 deg.C. |
