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:
Sep. 15, 1981
Filed:
Feb. 15, 1980
Carmine A DiPippo, Longmeadow, MA (US);
James River Graphics, Inc., South Hadley, MA (US);
Abstract
Negative-working diazography material is comprised of (i) at least one diazonium compound, (ii) at least one acid labile enolic, preferably phenolic blocked-coupler adapted to be converted in the presence of acid to an active azo-coupling component, (iii) at least one light-sensitive acid progenitor, and (iv) at least one carboxylic acid anhydride. The diazonium compound can itself concurrently function as the acid progenitor, e.g., when complexed with a Lewis acid. Upon imagewise exposure to light, acid catalyst is photochemically liberated, thus unblocking coupler molecules such that dye image forms under alkaline developing conditions only where the material has been irradiated. Under alkaline developing conditions, the anhydride reacts to render the unused diazo component remaining in the unexposed areas inactive.