Co-developers for black-and-white photothermographic elements
AssigneeEastman Kodak Company
InventorsDoreen C. Lynch, Paul G. Skoug
Life of this patent
Estimating the term…
Abstract
Novel co-developer compounds are useful in combination with hindered phenol developers to produce high contrast black-and-white photothermographic elements. The co-developer compounds have the formula wherein: Y is H, a metal (preferably, an alkali metal), or an alkyl group (preferably, an alkyl group having from 1 to 4 carbon atoms), and the solid curved line represents the atoms and bonds necessary to complete a ring structure (preferably a 5 or 6 membered ring structure). The photothermographic elements may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation-sensitive imageable medium.
Claims15
A black-and-white photothermographic element comprising a support having coated thereon an imaging coating comprising:
- (a) a photosensitive silver halide;
- (b) a non-photosensitive, reducible silver source;
- (c) a reducing agent system for silver ion;
- and
- (d) a binder;
- wherein the reducing agent system comprises:
- (i) a hindered phenol;
- and
- (ii) a non-fogging co-developer either of the formula
- wherein Y in either formula is H, a metal cation, or an alkyl group, Z is a sulfur or nitrogen atom, and the solid curved line in either formula represents the carbon, oxygen, sulfur or nitrogen atoms and bonds necessary to complete a 5- or 6-membered main ring that can have at least one pendant or fused ring attached thereto.
Dependencies are inferred from the claim text.