Multisalt Preservatives and the Treated Wood/Water Relationship
Abstract
SYNOPSIS Multisalt preservative-treated and untreated wood blocks were exposed to moist soil to determine the hygroscopicity and hence the fixation of the preservatives. The effects of companion cations and anions of the formulation salts on the hygroscopicity of the preservatives in the treated wood were studied. Other factors affecting the hydrophylic character of wood were also studied. It was found that the rate of moisture uptake from wet soil, with moisture contents above the critical moisture content2 for wood could be reduced substantially by treatment of the blocks with specially selected formulations of copper-chrome-arsenate (CCA) applied by means of special treatments. It is proposed that the retardation in moisture uptake is caused by a layer of insoluble salt on the cell walls of the treated wood.