Dyes, inks and their use in ink jet printing
Publication Date: 2004-May-19
The IP.com Prior Art Database
The present disclosure relates to aqueous inks comprising a blue or violet dye that are especially suitable for the printing of various recording materials (such as paper, film, cloth) with the ink jet printing method.
The present disclosure relates to aqueous inks comprising a blue or violet dye. The inks underlying the present disclosure are especially suitable for the printing of various recording materials (such as paper, film, cloth) with the ink jet printing method. By the ink jet printing method, images and characters are usually printed by subtractive color mixing of inks of four colors, namely Yellow (Y), Magenta (M), Cyan (C) and Black (K). Printed inks are subject to high demands in terms of their optical density, color brilliance and fastness to humidity, light and atmospheric pollutants. In order to widen color gamut and improve color reproduction of the formed image, supplementary color inks, such as Orange, Green, Blue or Violet, are increasingly implemented in addition to CMYK inks.
It has now been found that certain Blue and Violet dyes enable to formulate ink jet inks with outstanding color brilliance. The obtained inks can markedly improve color reproduction in the blue and violet regions when used in combination with a CMYK ink set or with a CMYK ink set already complemented with additional color inks, such as Light Cyan, Light Magenta, Orange, Green or Red inks. The Blue and Violet dyes in question are denoted by the following Color Index (C.I.) names: C.I. Reactive Blue 269, C.I. Reactive Blue 268, C.I. Acid Blue 225, C.I. Acid Blue 260, C.I. Reactive Violet 2, C.I. Acid Violet 109.
Inks according to this disclosure typically comprise:
(i) from 0.5 to 10 parts of a Blue or Violet dye as described above
(ii) from 1 to 60 parts of water-soluble organic solvent or a mixture of such solvents
(iii) from 30 to 98.5 parts of water
wherein all parts are by weight and the sum of the parts (i) + (ii) + (iii) = 100. Examples of suited organic solvents are described, inter alia, in U.S. Pat. 6,635,747 (column 9). The inks may also contain additional components conventionally used in ink jet printing inks, for example viscosity an...