about 6 carbon atoms, R7 is an alkyl or aryl group containing not more than about 10 carbon atoms and Y is an...http://www.google.com/patents/US5187282?utm_source=gb-gplus-sharePatent US5187282 - Sulfonated xanthene dyes, and photographic products and processes employing these dyesAdvanced Patent SearchPublication numberUS5187282 APublication typeGrantApplication numberUS 07/683,452Publication dat