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. 01, 1976
Filed:
Feb. 07, 1975
Nicholas P Greco, Pittsburgh, PA (US);
David A Webb, Valencia, PA (US);
Koppers Company, Inc., Pittsburgh, PA (US);
Abstract
An improved creosote wood preservative that has a light color and that forms a non-sticky crud deposit is prepared from a coal tar creosote. The coal tar creosote is distilled to an end temperature in the range of 395.degree. to 410.degree.C. at atmospheric pressure. This distillation produces a distillate and a pitch residue. The distillate is contacted with at least 1% by weight of one or more of the following caustic compounds: alkali metal alcoholates of alkali metal hydroxides to produce the improved creosote wood preservative. The pitch residue from distillation is recovered and it is utilized in the production of various pitch products or in combustion for its fuel value.