| 摘要 |
318,580. Wolff & Co., and Weingand, R. Sept. 6, 1928, [Convention date]. Condensation products of urea or its derivatives with aldehydes.-The manufacture of films and the like from condensation products of urea or its derivatives with aldehydes is effected by applying a solution of the condensation product containing a known softening agent to a travelling base, solidifying the solution on the base, and removing the product from the base, the operations being carried out in the time that elapses between the production of a viscous initial solution and a product that is not superficially sticky. The softening agent, which may be glycerine, glycol, or methylcyclohexyl adipate, may be added to the initial solution after the condensation has begun, and the solidification of the film may be effected at 70-100‹ C. |
