Patent ID: 7160664

Claim:
A magenta dye combination comprising at least a first magenta dye of the following structure I: wherein X is a NR 3 R 4 group or a hydroxyl group, wherein R 3 and R 4 may be same or different and are independently selected from an alkyl, alkenyl, aryl, aralkyl, or cycloalkyl group; Y 1 and Y 2 each independently are selected from a carbon atom or a nitrogen atom, provided that one of Y 1 and Y 2 is a nitrogen atom; Z is an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocyclic ring which may be condensed with another ring; and R 1 and R 2 are each independently selected from a hydrogen atom, halogen atom, alkyl, alkenyl, alkoxy, alkylamino, acetamido, sulfonamide, aryl, aralkyl, or cycloalkyl group; and a second magenta dye of the structure II: wherein: R 1 represents an alkyl group having from 1 to 10 carbon atoms, a cycloalkyl group having from 5 to 7 carbon atoms, or an aryl group having from 6 to 10 carbon atoms; R 2 represents an alkoxy group having from 1 to 10 carbon atoms, an aryloxy group having from 6 to 10 carbon atoms, naphthoxy, NHR 5 or NR 5 R 6 ; R 3 and R 4 are each independently R 1 , or either or both of R 3 and R 4 can be joined to the carbon atom of the aromatic ring at a position ortho to the position of attachment of the anilino nitrogen to form a 5- or 6-membered ring, or R 3 and R 4 can be joined together to form a 5- or 6-membered heterocyclic ring with the nitrogen to which they are attached; R 5 and R 6 each independently represents an alkyl group having from 1 to 10 carbon atoms, a cycloalkyl group having from 5 to 7 carbon atoms, or an aryl group having from 6 to 10 carbon atoms, or R 5 and R 6 may be joined together to form, along with the nitrogen to which they are attached, a 5- or 6-membered heterocyclic ring; and Z represents hydrogen or the atoms necessary to complete a 5- or 6-membered ring.