Improvement of discolouration resistance of beech veneers against light by treatment with hot water

Colour measurements in the visible region using a scale of Datacolor showed that beech veneer treated with boiling water discolours significantly less under the action of light than untreated veneer. The change in colour value of the treated wood containing red heartwood was only half of the one in the corresponding untreated wood. In wood without red heartwood, the colour change induced by the ultraviolet radiation could even be reduced to a fifth of that of the not treated veneer. Therefore, the pretreatment with boiling water seems to be a suitable method to reduce significantly the discolouration caused by exposure to light. Treatment with boiling water also results in veneers with homogenous colour distribution.