WATERFAST INK JET INKS AND IMAGES THEREFROM
Original Publication Date: 1997-Apr-30
Included in the Prior Art Database: 2004-Apr-08
Xerox Disclosure Journal
Disclosed is a method of using dye-based ionic ink jet inks whereby the ink jet ink becomes substantially waterfast upon application to a print substrate. The method includes treating a print receiving substrate with a precipitant composition and jetting an ionic ink jet ink onto the print substrate. The precipitant composition includes water and an ionic precipitant of opposite ionic charge from the ionic ink jet ink. The print substrate may be treated during formation of the print substrate or after formation of the print substrate and before jetting the ionic ink jet ink onto the print substrate. By this method, the ionic precipitant composition reacts with the oppositely charged ionic ink jet ink to form a precipitant on the print receiving substrate that is substantially waterfast. Thus, a method for obtaining waterfast images from ink jet inks comprises: treating a print substrate with a precipitant composition; and jetting an ionic ink jet ink onto the print substrate, wherein the precipitant composition comprises water and an ionic precipitant of opposite ionic charge from the ionic ink jet ink. The precipitant composition can be, for example, cationic and the ink jet ink is anionic. Alternatively, the precipitant composition can be anionic and the ink jet ink is cationic. The print substrate can be, for example, plain paper, coated paper, transparency, and the like materials. In embodiments, the large cation can be a cationic salt, a phosphonium salt, a sulfonium salt, an ammonium salt, or an aluminum salt. The cationic salt can be comprised of a metal such as iron, aluminum, calcium, zinc, magnesium, barium, tin, and the like.