Surface roughness characterisation of multilayer polymer films for graphicarts applications

The paper contains an experimental study about the relationship between sur face roughness of films for graphic arts applications, measured by means of average roughness and peak count, and reflectometer measurements by using different incidence angles of light. Samples studied were multilayer materi als for graphic arts, obtained by spreading adherent emulsion layers over b oth sides of a substrate of polyethyleneterephtalate (PET) film. Different surface roughness were obtained by spreading a protective coating with diff erent amounts of matizant agent (emulsion of gelatine and polymeric spheres of 3 +/- 1 mum of diameter). Good correlations between reflectometer measurements and surface roughness were found, showing that this optical technique is potentially a good way t o study the surface characteristics of these materials. (C) 2001 Elsevier S cience B.V. All rights reserved.