The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 25, 1991
Filed:
Mar. 30, 1990
William F Drinkard, Jr, Charlotte, NC (US);
Hans J Woerner, Mt. Pleasant, NC (US);
Drinkard Developments, Charlotte, NC (US);
Abstract
A method of preparing copper arsenate compositions having unique advantges in lower cost and higher performance for use in preparing chromated copper arsenate wood preserving formulations. These copper arsenate compositions are insoluble copper arsenate in water or as a dry reactive powder, have a mol ratio of As.sub.2 O.sub.5 to CuO of 1:4, and is readily soluble in chromic acid to form CCA wood preservatives. This copper arsenate is prepared by reacting suitable copper-bearing materials with arsenic trioxide and air or oxygen in ammoniacal solutions. Either or both of the starting raw materials, i.e., the copper and the arsenic, may be very impure, which impure materials were heretofore unsuitable for the production of copper arsenate.