申请人:Clark Bernard A.
公开号:US20080248433A1
公开(公告)日:2008-10-09
The invention provides a colour photographic element comprising at least one light-sensitive silver halide emulsion layer or a non silver-containing light-insensitive layer, in which at least one of these layers contains a colourless imidazole compound of formula (I) that undergoes less than 10% chemical or redox reaction directly with oxidized developer and which has a partition coefficient to enable the photographic speed of the element to be increased by at least 0.03 stop without increasing granularity, compared to the same element without the compound, wherein the compound of formula: (I) has the structure: wherein X is H or a substituent; Z represents the atoms necessary to complete an unsubstituted or substituted imidazole ring, which may form part of a fused unsubstituted or substituted ring system containing no further ring heteroatoms; wherein there is present at least one —NH group either in the imidazole ring or directly attached to the imidazole ring as part of X; provided that (a) when Z represents the atoms necessary to complete an unsubstituted or substituted benzimidazole ring, an —NH group is directly attached to the imidazole ring as part of X, and X is located between the imidazole nitrogen atoms; (b) when the —N—H group is located in the ring adjacent to the carbon atom bearing X, and X is located between the imidazole nitrogen atoms, the imidazole ring is not fused to a phenanthrene ring. The compounds of formula (I) increase speed without a concomitant increase in size of the light-sensitive silver halide grains.
本发明提供了一种彩色摄影元素,包括至少一层感光性银卤化物乳剂层或不含银的光不敏感层,其中这些层中的至少一层含有化学或氧化还原反应不超过10%的无色咪唑化合物(I)且该化合物具有分配系数,使得与不含该化合物的相同元素相比,元素的摄影速度至少提高0.03个档次而不增加颗粒度。其中,化合物的结构式为:其中X为H或取代基;Z代表需要完成未取代或取代咪唑环的原子,该环可能是未取代或取代环系的一部分,且不包含其他环杂原子;在咪唑环或直接附着于咪唑环上作为X的一部分至少存在一个—NH基团;前提是(a)当Z代表需要完成未取代或取代苯并咪唑环的原子时,—NH基团直接附着于咪唑环上作为X的一部分,且X位于咪唑氮原子之间;(b)当—N—H基团位于携带X的碳原子相邻的环中,且X位于咪唑氮原子之间时,咪唑环未融合到菲环中。该式(I)的化合物可以提高速度,而不会伴随着感光银卤化物颗粒的大小增加。