| abstract |
Styryl-naphthalene compounds, which are colourless or at most slightly coloured, have formula:- A-CH=CH-B-CH-A', where B is a naphthalene residue which has the A-CH=CH- and A'-CH=CH- groups in the 1,5- or 2,6-positions, A and A' are benzene residues, naphthalene residues or biphenyl residues and at least 1 of the ring systems A, A' and B has a (functionally modified) sulphonic acid group, a sulphone group, a (modified) carboxylic acid group or a nitrile group, and may also have 1 or more C is not >18 alkyl or alkoxy groups, halogen atoms or methylene dioxy groupings. The compounds are optical brighteners, for use in synthetic high-molecular polymers, semi-synthetic materials such as cellulose derivatives and casein synthetics, and natural materials such as textile fibres, natural resins, rubber, gutta-percha and balata. They can also be used as scintillators in photographic products. |