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:
Jul. 11, 2000
Filed:
Jun. 24, 1999
Siu C Tsoi, Watford, GB;
Peter J Twist, Gt. Missenden, GB;
Eastman Kodak Company, Rochester, NY (US);
Abstract
A class of pyrazolidone compounds suitable for use as electron transfer agents in photographic development comprises pyrazolidones substituted in the 1-position by an aromatic group that is substituted in the ortho, meta or para position by --O--CO--R, wherein R is a monovalent organic group having up to 24 carbon atoms. This ester group is hydrolyzable in an alkaline developer solution, thereby deactivating the electron transfer agents after a period of time and reducing the contamination effect of seasoning into the developer solution. Photographic recording materials can be developed in reactive association with the electron transfer agent. The electron transfer agent can be present in the photographic recording materials, or in develper solutions.