| abstract |
Aqueous inks are provided for use in vehicles employing from about 10 to about 40 wt % of one or more organic solvents; and optionally up to about 5 wt % of an additive independently selected from the group consisting of surfactant, buffer, biocide, and mixtures thereof. The inks comprise, by weight, from about 1 to about 10 wt % Reactive Black 31 dye in either or both of its hydrolyzed forms, namely vinyl sulfone form and ethyl hydroxy form. Ink-jet inks made using the Pacified Reactive Black 31 provide improved lightfastness across a range of printing media while providing reliable ink-jet pen performance. |