High gloss photo-like ink-jet papers based on capillary absorption have been used in ink-jet printing for about 15 years. Their strong advantage compared to swellable media is the fast ink absorption. This allows printing at highest printer speed, very high resolution, dye and pigment compatibility and strong laminate adhesion. The main drawbacks of such papers compared to polymer papers are often the lower permanence to light and to air-borne contaminants, as well as reduced color brilliance and black density when printed with dye-based inks. While great progress has recently been made in inkjet colorant development, the design of the receiving layer is a key contributor to print stability.This paper describes the design and properties of highly transparent nanoporous silica layers that provide a very large gamut and high maximum density with dye-based inks, high sharpness with minimum blurring. The gamut gain is particularly strong in the dark blue and red sector of the color space and in black, as areas of high ink load and strong depth penetration benefit most from layer transparency. The permanence of dyes in a high surface area nanoporous matrix depends, among others, on the chemical environment. The molecular covalent surface treatment of the silica during manufacturing of the dispersion influences the final humidity and ozone stability of dye-based inks. Photographic coatings allow deposition of precise multi-layer assemblies, which incorporate specific functions in layers to improve e.g. physical properties like gloss or scratch resistance.
Vincent Ruffieux, Pierre- Alain Brugger, Urs Fuerholz, Meinrad Schaer, Juerg Reber, "Nanoporous Inkjet Photo Paper with a High Dynamic Range" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP25), 2009, pp 543 - 546, https://doi.org/10.2352/ISSN.2169-4451.2009.25.1.art00038_2