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:
Apr. 24, 1990
Filed:
May. 15, 1989
Senzo Sasaoka, Kanagawa, JP;
Nobuaki Inoue, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A silver halide photographic material and an image forming method using such material are described, said material comprising a surface latent image forming silver halide emulsion layer unit on a support, and containing a hydrazine compound in at least one of said emulsion layer unit and other constituent layers, said emulsion layer unit being composed of at least two layers, with the silver halide emulsion present in a fine-grained low-sensitivity emulsion layer having a minimum average grain size being not more than 80% of the average grain size of a coarse-grained high-sensitivity silver halide emulsion having the maximum average grain size, and said silver halide photographic material attains a contrast of 10 or more in terms of gamma value when a developer containing at least 0.15 mol/liter of sulfite ions and having a pH of from 9.5 to 12.3 is used.