Patent ID: 8465578
Filing Date: 2013-06-18
Classification: C09D

Abstract:
1. An inkjet ink set for use with an inkjet printing system employing a near-infrared drying system, comprising at least a black ink and a yellow ink, wherein the yellow ink comprises a yellow colorant and dispersed nanoparticulate colloidal silica at a concentration of from 0.1 to about 10 wt %, and the black ink comprises a black colorant and dispersed nanoparticulate colloidal silica at a concentration of from 0 wt. % to at most ½ of the wt. % of the dispersed nanoparticulate colloidal silica in the yellow ink, wherein the dispersed nanoparticulate colloidal silica comprises hydrated silica particles which are absorbing in the near-IR spectrum from 750 nm to 900 nm, and wherein the pH of the inks is greater than 7.5 and less than 9.0 so as to obtain improved drying with the near-infrared drying system.