| abstract |
A blowing agent combination comprising azodicarbonamide, zinc oxide and a benzenethiol sulphonic acid derivative having the general formula (I) <IMAGE> wherein R is a hydrogen atom, a C1-C4 alkyl radical and/or a chlorine atom, X is a number from 1 to 5, and R' is a C1-C4 alkyl radical, a C5-C6 cycloalkyl radical or a C7-C8 arylalkyl radical each of these radicals being optionally substituted by from 1 to 3 C1-C4 alkyl radicals, from 1 to 5 chlorine atoms and/or a carboxylic acid C1-C4 alkyl ester radical, or a radical having one of the general formulae (11a), (11b), (11c) or (11d). <IMAGE> <IMAGE> in which y is a number from 0 to 3, R'' is a C1-C6 alkylene radical or a xylylene radical which is optionally substituted by from 1 to 4 methyl radicals and/or from 1-4 chlorine atoms and R and X are as defined above; may be used as blowing agents. |