| abstract |
1344992 Optical brightening and UV agents KODAK Ltd 19 April 1971 [1 April 1970] 15514/70 Heading C2C [Also in Division C4] The invention comprises fluorescent brightening agents or U.V. absorbing agents which contain a group selected from an -OCON 3 , -CHBr 2 , -CBr 3 or a 1-diazo-4-oxo-1,4-dihydroaryl group or an azido group attached directly to an aryl ring. Suitable brightening agents are those of the coumarin or bis-benzoxazole series. The compounds may be prepared by various methods, e.g. from intermediates containing the reactive groups or by the introduction of the reactive groups into the otherwise finished molecule. For example, an azidophenoxy group may be introduced by reacting a compound containing a chlorotriazinyl or chloropyrimidinyl radical with 4-azido phenol. -CH(Br) 2 and -C(Br) 3 groups may be introduced by brominating an active methyl group. -OCON 3 groups may be introduced by reacting a compound containing the group -OCOCl with sodium azide. 1-Diazo-4-oxo-1,4 dihydroaryl groups may be prepared by diazotization of the appropriate 1-amino-4-hydroxyl aryl compound and treatment with a base. The compounds may be chemically bound to organic polymers by initiating a reaction between the reactive group and the polymer substrate by means of heat or radiant energy. |