The Influence of Stock Surface Properties on Grease Resistant Films

Introduction One of the main problems in applying a continuous film to a fibrous surface such as paper is that coating must cover fibers that lie in every direction. This produces a relatively rough mat, with some fibers protruding. The surface of paper varies, but all papers and board have a surface configuration resembling a range of mountains. In paper, the interstices can be loaded with fillers, but with boards, fillers are not practical due to the amount necessary. Thus, in coating board with a continuous film, the surface configuration of the board is this main determining factor of the amount of coating necessary. Calendar treatment of board will tend to flatten the tops of the sharp peaks, but the stray fibers sticking up will not be decreased materially. To correctly balance the continuity and adhesion of a film with the surface configuration of the sheet to which it is applied is the problem of the grease resistant paper manufacturer