Control of Wrinkling in Paper Coating

Abstract

Paper and paperboard are essential packaging materials these days. Coated paper and paperboard material is a potential and effective substitute for non-biodegradable plastic material for cups. Extrusion and dispersion coating are widely used coating techniques to make paper a non-permeable material for liquid containment. Dispersion coating has an edge over conventional extrusion coating due to lower coating weight and recyclability. Paper is less stiff than paperboard which makes it difficult and more challenging to process it through dispersion coating. Along with other challenges and problems encountered during the dispersion coating of paper, wrinkling during coating process is a common problem which is hindering the commercial success of this technique. The aim of this study is to find out the possible causes and reasons of wrinkling of paper web during dispersion coating of paper. Furthermore, the study aims to suggest and test different settings and sets of parameters to minimize and prevent the wrinkling problem of paper web during its dispersion coating. The study included the theoretical study of possible causes and reasons behind wrinkling phenomenon of paper web. Additionally, it involves the experimental testing and trials on pilot line to evaluate the effect of proposed settings and sets of parameters to encounter the wrinkling problem during processing and to find the optimal settings and parameters for dispersion coating of paper.