| abstract |
A dye which, in the free acid form, has the formula <CHEM> wherein W is COOH X is selected from H, COOH, SO3H, halo, hydroxy, nitro, cyano, C1-6-alkyl, C1-6-alkoxy and C1-6-acylamino; Y is H, COOH or SO3H; Z is H, COOH or SO3H; R & R<1> are each independently H or C1-6-alkyl substituted by 0, 1 or 2 -COOR<2> groups; and R<2> is H or C1-6-alkyl; provided that there are at least two COOH groups and that the number of COOH groups is equal to or greater than the number of SO3H groups. The dye is adapted for the preparation of inks for use in ink jet printing in which it displays high water-fastness on paper. |