| abstract |
The present invention relates to a process for the preparation of polyurethane foams capable of being flame laminated and high frequency welded, comprising reacting: (a) polyisocyanate, (b) a compound having a molecular weight of from 400 to 10,000 containing at least two isocyanate-reactive hydrogen atoms and (c) a dialkoxy-phosphonyl-N-alkyl-formic acid amide of the formula: <IMAGE> wherein m represents an integer of from 1 to 3, n represents an integer of from 0 to 8, X represents halogen, hydrogen, C1 to C6 alkyl, -OR, or <IMAGE> R represents C1 to C6 alkyl, R1 represents hydrogen, C1 to C10 alkyl, C1 to C10 alkylene, C6 to C10 aryl or C6 to C10 arylene, and R2 and R3, which may be the same or different, represent C1 to C10 alkyl in the presence of water and/or blowing agent. The present invention also relates to dialkoxy-phosphonyl-N-formic acid amides. |