Alternative Chemistry for Paper: Surface Size With High Performance and a Large Window of Operation, 1995 Papermakers Conference Proceedings

Yi-Guan Tsai Akzo Nobel Anthony R. Colasurdo Akzo Nobel Carlos Cordoba Akzo Nobel, Eka Nobel Iberica, S.A. As the alkaline paper learning curve increases in the paper industry, more and more paper mills are taking advantage of surface sizing agents to alter the surface properties of alkaline paper. Paper properties such as sizing, surface strength, coefficient of friction, as well as printing quality, can be improved significantly by using a surface sizing agent. There are three basic types of chemistries: 1) SMA (styrene maleic anhydride copolymer), 2) SAA (styrene acrylic acid copolymer), and 3) PUD (polyurethane dispersions). These chemistries have been used in the industry as an effective surface sizing agent, with some limitations on application. In this paper, a fourth chemistry, SAE (styrene acrylate emulsion) for surface sizing will be discussed. SAE chemistry is specially designed to overcome some of the weaknesses that exist in contemporary surface sizing chemistries, i.e., foaming, pH sensitivity and low tolerance to salt concentration in the size press solution. This new chemistry provides alkaline paper with a high degree of sizing, good toner adhesion, sufficient coefficient of friction and superior inkjet printing quality.