Co-milled pigments in ink jet ink

Claim 1

An aqueous ink jet ink composition comprising a humectant in an amount of up to about 70% by weight of said composition, and from about 0.5% to about 30% by weight of a co-milled mixture of Pigment Yellow 74 and a pigment having the following structure: ##STR6## wherein: R 1 , R 2 and R 5 each independently represents H; a substituted or unsubstituted alkyl group of 1 to about 10 carbon atoms; a substituted or unsubstituted aryl group of about 6 to about 10 carbon atoms; or a substituted or unsubstituted hetaryl group of about 5 to about 10 atoms; R 3 and R 4 each independently represent the groups listed above for R 1 , R 2 , and R 5 ; a substituted or unsubstituted alkoxy group of 1 to about 10 carbon atoms; a substituted or unsubstituted aryloxy group of 6 to about 10 carbon atoms; a substituted or unsubstituted alkoxycarbonyl group; an alkyl-, dialkyl-, aryl-, diaryl-, or arylalkyl-carbamoyl group; an alkyl-, dialkyl-, aryl-, diaryl-, or arylalkyl-sulfamoyl group; an acylamino group; a sulfonylamido group; an alkyl-, dialkyl-, aryl-, diaryl-, or arylalkyl-amino group; or a ureido group; with the proviso that only one of R 1 , R 2 , R 3 , R 4 and R 5 is not H.