| 摘要 |
The present invention provides the new bis-stilbene compounds, which are useful as optical brighteners and correspond to the formula R1 - CH = CH - X - CH = CH - R2 in which X represents a diphenyl residue bound in positions 4 and 4' to the =CH- groups; R1 and R2 independently of each other, each represents a monocyclic benzene residue, a diphenyl, naphthyl or pyridyl residue, and in which at least one of the cyclic systems R1, R2, X contains a possibly functionally modified sulphonic acid group, a sulphone group, a possibly functionally modified carboxylic acid group, a nitrile, hydroxyl, mercapto or methyl group. |
