Microscopic Assessment of the Effect of Saw-Textured Pinus radiata Plywood Surface on The Distribution of a Film-Forming Acrylic Stain

摘要

The micro-morphology of the wood-coating interface of saw-textured Pinus radiata plywood panels, which had been coated with a film-forming stain, was examined using a range of microscopic techniques. The surface appearance and tissue deformation characteristics of saw-textured plywood and the pattern of distribution of the applied coating were observed by combined light, confocal, and scanning electron microscopy. The saw-textured surface was highly irregular, with surface tissues greatly distorted, being bent, twisted, and occasionally detached, and showing extensive cell wall cracking. The applied coating conformed closely to the contours of the saw-textured surface, resulting in a highly variable film thickness. The film was thickest in the grooves and thinnest over the ridges, and in places discontinuous, particularly where wood cells protruded out of the wood surface. These and other salient features of the surface of saw-textured plywood are discussed in relation to the pattern of the applied acrylic stain topcoat.