Patent ID: 7241719

Claim:
A thermal dye transfer imaging donor element comprising a yellow dye donor containing a combination of two or more yellow dyes, the combination of yellow dyes exhibiting an RMS error of less than 0.015, wherein at least two of the yellow dyes are selected from a dyes of Formula I, II or III: wherein: R 1 is an alkyl or allyl group of from 1 to 6 carbon atoms; R 2 is any of the groups as described for R 1 , or represents the atoms which when taken together with R 3 form a 5- or 6-membered ring; R 3 is an alkyl group as described above for R 1 , an alkoxy group of from 1 to 6 carbon atoms, or represents the atoms which, when taken together with R 2 , forms a 5- or 6-membered ring; R 4 is an alkyl group as described above for R 1 , or an aryl group of from 6 to 10 carbon atoms; and R 5 is any of the groups as described for R 4 ; wherein: R 6 is an alkyl or allyl group of from 1 to 6 carbon atoms; R 7 is any of the groups as described for R 6 , or represents the atoms which when taken together with R 8 forms a 5- or 6-membered ring; R 8 is an alkyl group as described above for R 1 , an alkoxy group of from 1 to 6 carbon atoms, or represents the atoms which, when taken together with R 7 , forms a 5- or 6-membered ring; and R 9 is cyano or —CONR 10 R 11 , where R 10 and R 11 each independently represents an alkyl group having from 1 to 6 carbon atoms; a cycloalkyl group of from 5 to 7 carbon atoms; an allyl group; an aryl group of from 6 to 10 carbon atoms or a heteroaryl group of from 5 to 10 atoms; wherein: R 10 represents methyl; an alkoxy group having from 1 to 10 carbon atoms; an aryloxy group having from 6 to 10 carbon atoms; or an acyl, carbamido, carboalkoxy, or amino group; R 11 represents an alkyl group of from 1 to 10 carbon atoms; a cycloalkyl group of from 5 to 7 carbon atoms; or an aryl group of from 6 to 10 carbon atoms; and R 12 and R 13 each independently represent alkyl groups having from 1 to 6 carbon atoms; a cycloalkyl group of from 5 to 7 carbon atoms; an allyl group; an aryl group of from 6 to 10 carbon atoms; or a heteroaryl group of from 5 to 10 atoms.