Surface Friction of Feather Powder Coated Films

Abstract

The effect of relative humidity (RH) on feather-powder-coated polyethylene terephthalate (PET) films was evaluated with respect to surface friction, surface roughness and compression properties. Three different feather powder contents in polyurethane printing layers were coated on PET films using a gravure printing method. The friction coefficient of the feather powder coated films was lower than the reference films. Both the friction coefficient and compression deformation increased slowly at low RH and then rose sharply above 80% RH. Therefore, to minimize the degradation of feather powder coatings and increase the friction coefficient at high RH, a feather powder content of more than 20 wt% and 24 μm print thickness are required for moisture sensitive materials. The nature of friction in feather powder coated films involves adhesion at the point of contact with the film in accordance with compression deformation of the feather powders.