Filled Barrier Dispersion Coatings, 1999 Coating Conference Proceedings

Mika Vähä-Nissi & Antti Savolainen

Tampere University of Technology

Paper Converting Institute

Barrier dispersion coatings are usually modified with fillers in order to improve runnability with the existing coaters, blocking resistance, repulpability, optical properties, and cost efficiency without sacrificing the barrier properties. Important factors are e.g. pigment particle shape, chemical nature, and adhesion between binder and particles.

The object of this study was to compare the effect of different pigments and pigmentation levels on the properties of barrier dispersion coatings, the most important properties being water vapor and grease resistance. The effect of the critical pigment volume concentration on the barrier values is obvious, but the performance of the coating can be controlled by a suitable choice of fillers. Also the different mechanisms of grease and water vapor barrier are indicated. Folding of filled barrier coatings easily destroys the grease barrier due to pinholes and cracks in spite of a constant or improved barrier of flat substrate.