Photographic elements, processes for forming images in photographic elements and new compounds are disclosed. Generally, the invention relates to immobile compounds which can be used to provide positive images from negative recording-developing photographic materials such as negative silver halide emulsions. The compounds contain a photographically useful group such as a dye or dye precursor and are capable of releasing said photographically useful group under alkaline conditions, and are also capable of reaction with an oxidized silver halide developing agent before substantial release of said photographically useful group occurs, to provide a reaction product having a substantially lower rate of release of said photographically useful group. In specific embodiments, the compounds of this invention contain an electrophilic cleavage group located in the linkage between a ballast group and a photographically useful moiety wherein said electrophilic cleavage group is a carbamic acid derivative.
本发明涉及摄影元素、形成摄影元素中图像的过程和新化合物。一般而言,本发明涉及不可移动的化合物,可用于从负记录-显影摄影材料(如负
银卤乳剂)中提供正图像。所述化合物包含一个摄影有用基团,例如
染料或
染料前体,并能在碱性条件下释放所述摄影有用基团,并且在所述摄影有用基团实质释放之前,还能与氧化的
银卤显影剂发生反应,从而提供具有显著较低的所述摄影有用基团释放速率的反应产物。在具体实施例中,本发明的化合物包含位于球状基团和摄影有用基团之间的连接中的亲电解剖基团,其中所述亲电解剖基团是一个
氨基甲酸酯衍
生物。