Fixation of compressive deformation of wood by wet heating under atmospheric pressure

By impregnating wood with organic liquids such as ethylene glycol and glyce rin and heating at about 80 degrees C, high swelling was obtained in a shor t period. The wood was then compressed in the direction perpendicular to th e grain and heated at 180 degrees C for more than 60 min to produce compres sed wood with high dimensional stability. It was confirmed that liquid rema ined in the wood cell wall alter heating at high temperature, indicating th at deformation fixation occurred because wood constituents were heated unde r swelling conditions at high temperature. We attempted treatment with aqueous solutions, which is advantageous with r egard to efficiency of impregnation, rinsing after processing, and reductio n of costs. Also high dimensional stability was obtained by treatment with aqueous solutions of 40% or more glycerin as a swelling agent. Using an aqu eous solution of 60% glycerin supplemented with 0.2% sulfuric acid, complet e fixation of deformation was obtained by heating at 180 degrees C and comp ression for shorter than 10 min.