Improved process for impregnating articles of wood, tissue, paper, cardboard and other substances with varnishes of synthetic resins and means for carrying said process into effect

摘要

329,066. Manufacture de Machines Auxiliaires pour l'ElectricitÚ et l'Industrie, and Texier, D. A. L. March 6, 1929. Waterproofing; proofing processes and compositions; wood, treating with liquids and gases.- After articles of wood, tissue, paper, cardboard, metal, or other material have been impregnated with a solution of a synthetic resin, the solvent is extracted and the resin polymerized by subjecting the articles to a gaseous atmosphere which will absorb the solvent, is condensable at ordinary temperatures and which possesses a high specific heat. The solvent is thereby more readily condensed than when absorbed in an atmosphere of ordinary air, and, owing to the higher specific heat of the gas, the polymerization is effected more quickly at a given temperature when using such gas than is the case when using ordinary air. In particular, dry steam is used when an alcoholic solution of phenolformaldehyde condensation product is the impregnating agent. An apparatus for carrying out the process comprises a chamber 1 in which the impregnated articles are placed, a water or air-cooled condenser 7, a blower 3 and a heater 2 having an inlet 15 for steam. The valve 10 is opened, valve 11 closed, and, after air has been circulated for some time, steam is admitted to the circuit through the valve 15.