Negative-working diazo type photoreproduction having improved pH control
AssigneeJames River Graphics, Inc.
InventorRobert C. Desjarlais
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Abstract
Negative-working diazography formulation is comprised of (i) at least one hexafluorophosphate diazonium salt adapted to photolytically cleave into an acid catalyst, (ii) at least one acid labile enolic, preferably arylenolic blocked-coupler adapted to be converted in the presence of acid to an active azo-coupling component, and (iii) an effective amount of an additive, such as p-toluenesulfonyl benzamide, capable of controlling the pH of films prepared from said formulation when subjected to a clearing step as defined herein.
Claims26
A light-sensitive diazography formulation comprising (1) at least one light-sensitive hexafluorophosphate salt of a diazonium compound adapted to photolytically cleave into an acid catalyst;
- (ii) at least one acid labile arylenolic blocked-coupler adapted to be converted in the presence of acid to an active azo-coupling species;
- and (iii) an effective amount of at least one additive represented by the structural formula:
- ##STR86## wherein R is selected from the group consisting of aryl of from about 6 to about 10 carbons, alkyl of from about 1 to about 12 carbons, aralkyl wherein aryl is from 6 to about 10 carbons and the alkyl is from about 1 to about 5 carbons, R' is selected from the group consisting of hydrogen, alkyl of from about 1 to about 12 carbons, aryl of from 6 to about 10 carbons, alkoxy of from about 1 to about 12 carbons, alkylthiomethyl of from about 1 to about 5 carbons, alkoxymethyl wherein the alkyl group contains from about 1 to about 5 carbons, trifluoroalkyl of from about 1 to about 3 carbons, aralkyl wherein the aryl thereof has from 6 to about 10 carbons and the alkyl thereof contains from about 1 to about 5 carbons, amino, and alkyl substituted amino of from about 1 to about 5 carbons, said effective amount being sufficient to reduce acid discoloration and bloom.
A light-sensitive diazography formulation comprising (i) at least one light-sensitive hexafluorophosphate salt of a diazonium compound adapted to photolytically cleave into an acid catalyst;
- (ii) at least one acid labile enolic blocked-coupler adapted to be converted in the presence of acid to an active azo-coupling species;
- and (iii) an effective amount of at least one additive represented by the structural formula:
- ##STR87## wherein R is selected from the group consisting of aryl of from about 6 to about 10 carbons, alkyl of from about 1 to about 12 carbons, aralkyl wherein aryl is from 6 to about 10 carbons and the alkyl is from about 1 to about 5 carbons, R' is selected from the group consisting of hydrogen, alkyl of from about 1 to about 12 carbons, aryl of from 6 to about 10 carbons, alkoxy of from about 1 to about 12 carbons, alkylthiomethyl of from about 1 to about 5 carbons, alkoxymethyl wherein the alkyl group contains from about 1 to about 5 carbons, trifluoroalkyl of from about 1 to about 3 carbons, aralkyl wherein the aryl thereof has from 6 to about 10 carbons and the alkyl thereof has from about 1 to about 5 carbons, amino, and alkyl substituted amino of from about 1 to about 5 carbons, said effective amount being sufficient to reduce acid discoloration and bloom.
Dependencies are inferred from the claim text.