| 摘要 |
<p>The essential feature of this invention lies in the fact that in 100 parts by weight of reactive solvent containing water not more than 30 % by weight, being a compound or mixture of compounds of molecular mass not above 500, containing hydroxymethyl groups, their ether derivatives, semiformals or formals, at reaction temperature within 60 to 180 °C, 10 to 200 parts by weight of melamine is dissolved, and the reaction mixture thus formed is held in the reaction temperature until the desired uniformity, viscosity, softening point and crosslinking is achieved, the said reactive solvents include products of reaction with formaldehyde of aliphatic bonds C-H of compound with sensitizing groups located in the position alfa, preferably ketones, aldehydes, nitrocompounds and derivatives thereof. Auxiliary agents may be admixed to the resin prior to crosslinking to facilitate bringing the mixture to the desired degree of crosslinking.</p> |
