摘要:
Compounds of the general formula R--CH.dbd.CH--W--CH.dbd.CH--R.sup.1 are described in which R and R.sup.1 are independently phenyl, diphenyl, naphthyl, indyl, tetrahydronaphthyl or acenaphthenyl and W is divalent phenyl, diphenyl, naphthyl, tetrahydronaphthyl or acenaphthenyl group, which groups may be substituted, the compounds containing at least one non-aromatic ring. Such compounds are useful as optical whitening agents, for example in textile material or paper.