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.

Date of Patent:
Nov. 14, 1989

Filed:

Sep. 01, 1987
Applicant:
Inventors:

Tatsuo Heki, Kanagawa, JP;

Noriyuki Inoue, Kanagawa, JP;

Shigeo Hirano, Kanagawa, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03C / ; G03C / ;
U.S. Cl.
CPC ...
430410 ; 430598 ;
Abstract

A method for forming a direct positive image by the steps of (a) imagewise exposing a light-sensitive material including a support having thereon at least one photographic emulsion layer containing a nonprefogged silver halide capable of forming an internal latent image and (b) developing the exposed material in the presence of a nucleating agent containing a combination of at least one quaternary heterocyclic compound and at least one hydrazine compound. The resulting direct positive has sufficiently high maximum density and low minimum density, and satisfactory stability over time.


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