The present invention relates to a novel class of compounds which absorb light at wavelengths greater than 350 nm and are useful as fluorescers or as photoinitiators. The present invention provides compounds of the formulas (I) and (II) and their equivalents (the nomenclature of the compounds used herein is based on the numbering of positions as shown in formula (I)): ##STR1## where: when W is .dbd.O, W.sup.1 is hydrogen or --OR.sup.9 and when W is .dbd.NR.sup.+.sub.2, W is hydrogen or NR.sub.2.sup.+2, A is hydrogen, alkenyl, alkyl or an election withdrawing group, and the remaining groups are as defined in the disclosure.
本发明涉及一种新型化合物类,其吸收波长大于350nm的光,并可用作荧光体或光
引发剂。本发明提供了式(I)和(II)及其等效物的化合物(此处使用的化合物命名是基于式(I)中所示位置编号):##STR1## 其中:当W为.dbd.O时,W.sup.1为氢或--OR.sup.9,当W为.dbd.NR.sup.+.sub.2时,W为氢或NR.sub.2.sup.+2,A为氢、烯丙基、烷基或电子吸引基,其余基团如本说明书所定义。