| 摘要 |
PURPOSE:To provide a compsn. of molding sand which improves the refractoriness of a casting mold and permits casting of a product equiv. to the casting formed by a casting mold subjected to mold coating even if molding coating is not applied to the mold at all with some casting products by incorporating a synthetic resin binder formed by modifying the conventional synthetic resin binder with an alkyl silicate into said compsn. CONSTITUTION:This cold curable compsn. for molding sand contains the synthetic resin binder formed by modifying the conventional known synthetic resin binder for which a furan resin, phenolic resin, urethane resin, etc. are used with the alkyl silicate such as ethyl silicate. A method for adding the alkyl silicate simultaneously with kneading of the molding sand and the synthetic resin binder is preferable as a method for modifying the synthetic resin binder by the above-mentioned alkyl silicate. The compsn. for molding sand of this invention has the characteristics to improve the refractoriness of the casting mold while making best use of the characteristics intrinsic to the synthetic resin binder and in addition, the compsn. is highly effective in simplifying a mold coating stage as compared to the conventional compsn. and preventing burning.
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