Influence of Pigment Particle Size and Packing Volume on Printability of Glossy InkJet Paper Coatings

摘要

The optical properties and printability of ink jet coated papers are influenced by smoothness, surface chemistry and pore structure of the surface coating layer. To control these properties, the coating formulator must select the proper pigment(s) and binder(s), the two main components of any coating. For glossy ink jet papers, small particle, large surface area fumed silica and aluminum pigments have been shown to provide the desired properties for high quality glossy ink jet coated papers. However, their high cost and low make-down solids, in comparison to conventional pigments, has limited their use by the industry to these specialty grades. The focus of this study was to determine if the costs and application solids of fumed silica and alumina coatings could be improved by extending the pigments with less expensive compatible pigments. The effects of the resultant change in packing volume and particle size distribution on the optical properties and printability were determined. Blends capable of providing equal or better gloss and printability, at a reduced cost, were sought. It was determined that up to 30 parts of the fumed silica and alumina could be replaced with less expensive compatible pigments, without significant loss to the optical and printing properties of the glossy ink jet paper.