Use of a chemically modified clay as a replacement for silica in matte coated ink-jet papers

New techniques for modifying the surface of ink-jet papers are continuously being developed. The affordability of ink-jet printers has placed them in the forefront of home-use for digital printing technology. Thus, there is a demand on the paper substrate, whether coated or not, to respond to a variety of ink-jet operating conditions, while continuing to yield a product with high print quality. Coating formulations for ink-jet papers currently utilize precipitated or gelled silica with polyvinyl alcohol (PVOH) as the binder. This silica and PVOH formulation generates good optical, surface, and print qualities, yet leaves a lot to be desired from a runnability and coating preparation standpoint. The modified clay pigment offers potential as a substitute particle for the silica pigment in matte grades of ink-jet paper. The modified clay pigment offered significant improvements in coating preparation and runnability. The modified clay, however, could not match silica in producing the surface and bulk coating properties required for generating high print quality without the addition of a cationic additive.