Untersuchungen zum Wasseraufnahmekoeffizienten von Holz bei Variation von Holzart und Flüssigkeit

Investigations into the water absorption coefficients of timber with variations in timber and moisture type.

The absorption coefficient of liquids (water and a hydrophobic watery impregnating agent with an active agent of co-condensed nanoscale silanes; active agent concentration 20 %) by test pieces of beech, robinia and spruce was determined in the three main cutting directions: longitudinal, radial and tangential, in accordance with BS EN ISO 15148:2002. A substantially higher moisture absorption rate was found with the grain than perpendicular to it. Beech showed the highest, robinia the lowest moisture absorption coefficients. The moisture absorption was lower for the hydrophobic impregnating agent than for water. This affects the impregnation performance both with pressure impregnation and surface-applied impregnation.