GB543803A - Regranulated cork and methods of preparing same - Google Patents

Abstract

543,803. Distilling off liquids contained in cork. BAKELITE BUILDING PRODUCTS CO., Inc. April 29, 1940, No. 7681. Convention date. May 1, 1939. [Class 32] [Also in Groups XXIII and VI] Relates to a process for the production of a highly expanded "re-granulated" cork, having fungus-resistant properties which make it particularly suitable, instead of the ordinary commercial re-granulated cork, for the manufacture of insulating boards by the method described in Specification 540,832, [Group V]. and of a volatile phenol distillate, having fungicidal properties. The process consists in heating natural waste cork, in granules of about “ inch mesh, in a non-oxidising atmosphere at a temperature between 400‹F. and 600‹F. to remove a portion of the volatile constituents not exceeding 45 per cent. by weight of the cork, cooling the granules in the absence of pressure' to retain the highly expanded character imparted by the conditioned heating, and grinding them to produce a regranulated cork having a density under 6 pounds per cubic foot (and even as low as 3 pounds per cubic foot). These granules have a fungous resistant quality arising from the retention in them of some phenols arising from the baking process. The fungicidal product may be isolated by settling the 45 per cent. distillate referred to into an oily and an aqueous layer, fractionating the aqueous layer to remove a fraction boiling between 45‹C. and 96‹C. and collecting the remaining aqueous portion which is the fungicide. Specification 16935/15, [Class 145 (i)], also is referred to.