| 摘要 |
Photographic element comprising on a support at least one silver halide emulsion layer and a speed-increasing amount of dispersed benzoxazine or benzothiazine derivative corresponding to general formula I or II: <CHEM> wherein X is -O- or -S-, R<1> is hydrogen, alkyl, aryl, heterocyclyl, acyl, heterocyclylcarbonyl, alkyl- or aryl-carbamoyl, heterocyclylcarbamoyl, alkyl- or aryl-oxycarbonyl, or carboxy, R<2> is hydrogen, alkyl, alkyloxy, aryl, heterocyclyl, or hydroxy, and R<1> and R<2> together can represent a group of atoms completing a nucleus, and each of R<3> and R<4> (same or different) is hydrogen, halogen, alkyl, alkyloxy, aralkyloxy, aryl, alkenyl, acylamido, alkylamino, hydroxy, alkyl- or aryl-oxycarbonyl, alkyl- or aryl-oxycarbonyloxy, alkyl- or aryl-thio, or benzenesulphonyl.
|
