Patent ID: 7537619

Claim:
A method of treatment of betula wood to change the coloration thereof to a desired color transformation, said method comprising the step of: i) providing a treatment chamber having a water basin in a floor area thereof, said treatment chamber being maintained at atmospheric pressure during said treatment and having access means to introduce and position over said water basin betula wood having a humidity content of at least 25% in mass to be treated under atmospheric pressure in said treatment chamber, ii) closing said access means, iii) introducing steam from a steam generating means into said water basin to boil and agitate water therein for subjecting said betula wood to be treated to a hot water vapor environment to completely saturate the betula wood throughout the thickness thereof, iv) controlling the supply of said steam to control the temperature and humidity levels in said treatment chamber over a time span until said betula wood to be treated has obtained a desired color transformation throughout the thickness thereof, v) obtaining betula wood samples from said treatment chamber during said time span of said treatment to monitor the change in coloration of said samples until said desired color transformation is obtained, vi) cooling said treatment chamber for a predetermined period of time not to expose said heated betula wood to an abrupt atmospheric change, vii) removing said treated betula wood, fully impregnated with water vapors, after said predetermined period of time for further processing, and viii) drying said betula wood in conventional dryers.