Ink formulations by mixing anionic waterfast dyes containing two or more carboxyl groups

摘要: INK FORMULATIONS BY MIXING ANIONIC WATERFASTDYES CONTAINING TWO OR MORE CARBOXYL GROUPS ABSTRACT OF THE DISCLOSURE Inks are provided comprising (a) at least two dyes corresponding to the formula I wherein W is COOH, X H, or Y SO?H, Z SO3H, and R CH2COOH, CH2CH2COOH;with proviso that there COOH groups number of equal greater than SO3H groups, (b) a solvent which may be water mixture water-soluble organic provide excellent waterfast prints on paper. The inks preferably have pH from about 7 9.5. Also preferably, phosphate added reduce kogation metal chelating agent further nozzle clogging.