| 摘要 |
PURPOSE:To obtain a melamine resin easily soluble in water and capable of forming a cured product excellent in water and heat resistance, by adding toluenesulfonamide to a reaction product among melamine, formaldehyde and methyl alcohol. CONSTITUTION:A mixture containing 1mol of melamine, 1.8-2.8mol of formaldehyde and 0.1-2mol of methyl alcohol is reacted at a pH of 3-6.5 to a degree of methoxylation of 2-10%. To this reaction product is added 0.1-1mol, per mol of melamine used, of toluenesulfonamide, and the mixture is reacted or stirred at a pH of 7.5-9.5. The product is adjusted to a final pH of 7.8-8.5 by adding an acid or a base, if necessary, to obtain a melamine resin.
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