OPTICAL BRIGHTENER OB FBA 184OPTICAL BRIGHTENER OB-1 FBA 393OPTICAL BRIGHTENER KCB FBA 367OPTICAL BRIGHTENER KSN FBA 368OPTICAL BRIGHTENER FP-127 FBA 378OPTICAL BRIGHTENER ER-I FBA 199OPTICAL BRIGHTENER ER-II FBA 199:1OPTICAL BRIGHTENER CBS-X FBA 351and their intermediates.