Patent CA-2052843-A1 (CA)
Title: Yellow dye mixture for thermal color proofing
Inventor: EVANS STEVEN
IPC: B41M5/385
Filed: 1991-10-04
Abstract: YELLOW DYE MIXTURE FOR THERMAL COLOR PROOFING          Abstract of the disclosure A yellow dye donor element for thermal dye transfer comprises a support having thereon a dye layer comprising a mixture of yellow dyes dispersed in a polymeric binder, at least one of the yellow dyes having the formula:                               wherein:      R1 is a substituted or unsubstituted alkyl group of from 1 to about 10 carbon atoms; a cycloalkyl group of from about 5 to about 7 carbon atoms; or a substituted or unsubstituted allyl group;      R2 is any of the groups for R1 or represents the atoms which when taken together with Z form a 5- or 6-membered ring;  z is hydrogen; any of the groups for R1; alkoxy; halogen; aryloxy; or represents the atoms which when taken together with R2 forms a 5- or 6-membered ring;   Y is any of the groups for R1; alkoxy of from 1 to about 10 carbon atoms; halogen; or represents the atoms necessary to complete a 5- or 6-membered ring, thus forming a fused ring system; and n is a positive integer from 1 to 3; and at least one of the other of the dyes having the formula:       II   wherein:       R6 represents a substituted or unsubstituted alkyl group of from 1 to about 10 carbon atoms; a cycloalkyl group of from about 5 to about 7 carbon atoms; a substituted or unsubstituted allyl group; or an aryl group having from about 6 to about 10 carbon atoms;      R7 represents a substituted or unsubstituted alkoxy group having from 1 to about 10 carbon atoms; a substituted or unsubstituted aryloxy group having from about 6 to about 10 carbon atoms; NHR8; NR8R9 or the atoms necessary to complete a 6-membered ring fused to the benzene ring;      R3 and R4 each represents any of the groups for R6; or R3 and R4 can be joined together to form, along with the nitrogen to which they are attached, a 5-or 6-membered heterocyclic ring; or either or both of R3 and R4 can be joined to the carbon atom of the benzene ring at a position ortho to the position of attachment of the anilino nitrogen to form a 5- or 6-membered ring, thus forming a polycyclic system;      R5 represents hydrogen; a substituted or unsubstituted alkyl group of from 1 to about 10 carbon atoms; a cycloalkyl group of from about 5 to about 7 carbon atoms; a substituted or unsubstituted allyl group; carbamoyl; or alkoxycarbonyl;     R8 and R9 each independently represents any of the groups for R6; or R8  and R9  may be joined together to form, along with the nitrogen to which they are attached, a 5-or 6-membered heterocyclic ring;      m is a positive integer from 1 to 3; and G represents a substituted or unsubstituted alkyl or alkoxy group of from 1 to about 10 carbon atoms; halogen; aryloxy; or represents the atoms necessary to complete a 5- or 6-membered ring, thus forming a fused ring system. In a preferred embodiment of the invention, a third yellow dye is employed having the formula:     ¦¦¦                wherein:   R10 represents OR13 or NHR13;    R11 represents any of the groups for R3; R12 represents any of the groups for R4; R13 represents any of the groups for R6; J represents any of the groups for G; and p is a positive integer from 1 to 3.           This application is a continuation-in-part of copending U.S. Serial No. 606,399, filed October 31, 1990.