PROPIEDADES TECNOLÓGICAS DE LA MADERA QUE INFLUYEN EN LAS CARACTERÍSTICAS DE LA CHAPA Y EN LA CALIDAD DEL TRIPLAY

Abstract

The texture ofthe veneer surface is important to the adhesion process for its interaction with the amount of the adhesive to achieve good bonding of the conglomerate.
If smooth plywood surfaces are requiered, rough veneer implies an additional cost in adhesive, in wood wasted at the sander and in sanding paper.
The energy of the veneer surface, determined by the proportion of cellulose, defines the chemical adhesion of the glue, which is the ideal for strong bonding. If the veneer is exposed to enviromental oxidaction or coated with extractives, the adhesion characteristics diminish drastically, producing poor bondings, with direct effect on the quality of the plywood.
Surface inactivation due to poor drying practices also reduces the adhesion properties ofthe veneer. To overcome surface inactivation, special adhesive formulation and longer pressing time are requiered.
Veneer with high moisture content, affects the reactivity ofthe adhesive and with the heat from the press changes to vapor, producing high concentration of stresses at the glue line which tend to separte the veneer in the conglomerate.