Paper Coating

Improving the performance of barrier coatings

By M. Kleebauer, A. Harling, Papiertechnische Stiftung Heidenau

The aim of the project was to develop a concept of how to improve the effect and cost efficiency of barrier coatings against unwanted ingredients of paper for recycling (PfR) by optimally combining inorganic pigments with polymer coatings. The unwanted PfR in­gredients concerned were petroleum-derived hydrocarbons (MOSH, MOAH), phthalates (DEHP, DBP, DiBP) and benzophenone.
Starting with 11 different barrier substances and 14 different pigments, coating trials and formulation tests were conducted in the laboratory. The samples produced were evaluated, and new test methods were developed and validated to better assess the barrier effects after long- and short-time exposure by means of Tenax® migration. Polyvinyl alcohol, ethylene vinyl acetate copolymers and cellulose derivatives (hydroxyethyl cellulose and hydroxypropyl methylcellulose) were identified as barrier substances with good or very good effects.

Papiertechnische Stiftung Heidenau, D-01809 Heidenau, www.ptspaper.de, At Zellcheming-Expo: Hall 4.1, Booth H45

Optimization of coating with water-based barriers

By Tom Larsson, Senior Sales Manager at UMV Coating Systems

Sustainability is a hot topic among the societies worldwide. For reasons of personal health and environment, consumers are searching for «green» products and in addition to this, there are increased regulations set by authorities for packaging material and waste. New barrier products are needed to create an alternative to the use of conventional packaging solutions containing plastics, perfluorocarbon and wax.

The new generation of barrier products containing water-based barrier coating (WBBC) is normally a more expensive alternative than the conventional packaging solutions. Therefore, to make the new products with WBBC’s cost competitive, it is important to keep the production costs as low as possible. This means best achievable performance with the lowest coat weight possible.

UMV, SE-661 32 Säffle, www.umv.com, At Zellcheming-Expo: Hall 4.1, Booth D37