The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 01, 1994
Filed:
Dec. 16, 1992
Katsumi Hirano, Kanagawa, JP;
Katsumi Makino, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A silver halide photographic material comprising a support having provided thereon at least one silver halide emulsion layer, wherein the emulsion layer contains silver halide tabular grains having a diameter of not less than 0.15 .mu.m in an amount of not less than 70% of the total projected area of the total silver halide grains, wherein at least 50% of the total number of all tabular grains have a ratio of grain thickness (b) to the longest distance between two or more parallel twinning planes (a) of not less than 5, and wherein the emulsion layer or other hydrophilic colloidal layer contains a compound represented by formula (I): ##STR1## wherein Z represents a residual group of a heterocyclic ring to which at least one group selected from --SO.sub.3 M, --COOR.sub.1, --OH, and --NHR.sub.2 is bonded either directly or indirectly; M represents a hydrogen atom, an alkali metal atom, or --NH.sub.4 ; R.sub.1 represents a hydrogen atom, an alkali metal atom, or an alkyl group having from 1 to 6 carbon atoms; R.sub.2 represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms, --COR.sub.3, --COOR.sub.3, or --SO.sub.2 R.sub.3 ; and R.sub.3 represents an aliphatic group or an aromatic group. The photographic material exhibits high sensitivity, improved graininess, low fog, and improved low intensity reciprocity law failure.