Influence of Latex Binder Viscoelastic Properties on High Temperature Calendering Runnability, 2002 Coating Conference Proceedings

R. Carlsson, P. Salminen and M. Wilkström

The objective of this work was to investigate the influence of temperature-dependent flow properties (thermal flow) of paper latex binders on calender runnability in terms of deposit formation on the calender, especially at high surface temperatures. Four model SB-latexes with different temperature-dependent flow properties were used. The experiments were performed on coated liquid packaging board using an extended soft nip pilot calender with surface temperatures up to 250°C.

An SB-latex that showed comparatively high ability to flow in the 20 to 50°C range and rather low ability to flow over 80°C is shown to be the most suitable latex in this study for calendering at the highest temperature, 250°C. The results indicate that a latex binder for high temperature calendering needs to be optimized with respect to thermal flow properties. Ideally the binder should show relatively high flow at the conditions in the drier to minimize dusting and relatively low flow at the higher temperatures used in high-temperature calendering to minimize sticking.