SURF - Surface characterization of industrial large area products

The paper- and paperboard industries are undergoing a transition in terms of product specializations. A decreasing interest for Newspaper and harder competition in paperboard products forces the paper- and paperboard industries to start producing new products, where there is even higher demand on surface characteristics, since most products will undergo high quality print. This project will attempt to bridge the gap of modern industrial measurement needs for surface characterization.

Background

Prints and laminates on paper are becoming more and more sophisticated, raising the demand on the coated surface of paper and paperboard. The development has forced the paper and paperboard industries into a phase of transition, where they find new ways of producing paper based products with high quality coating, and new coatings enabling electronic functionality. This, to a certain extent, will change the product portfolio of the industry, and also enable the products to go into new product segments.

With a higher demand on quality follows a higher demand of measuring the parameters important for this quality. Currently, there are a few ways of characterizing topography, gloss etc in a lab environment, and a few ways of characterizing topography inline in the paper machine. The inline measurements for surface topography are not yet widely used, though. The industry needs to know what they are producing in real time in order to increase quality of their products, in the tempo that the end users dictate.

At STC, research on surface characterization has arisen within the field of roughness and topography characterization, and in the field of materials characterization and appearance, predominantly in the research area of measuring and modelling light scattering in paper and prints. In this project new measurement methods for surface characterization will be explored, developed, implemented and then prototyped and tested by the included industrial partners. The project result is intended to enable surface characterization for a number of industrial parameters, but also to answer research questions related to how the surface relates to, for instance, electrical parameters.

Objectives

One objective of this proposed research project is to develop measurement methods applicable for online/inline process control of coating quality in roll-to-roll manufactured flexible electronics. The objective will be met by using goniophotometric (angular resolved) spectral imaging, dark field 2D surface characterization and line of light laser triangulation. Reserachers will develop measurement methods, interpretational models and guidelines for industrial implementation of the measurement methods.