The U.S. Court of Appeals for the Federal Circuit has held that a process for the production of ethylene oxide using a catalyst "characterizable" by a mathematical efficiency equation could be infringed by a process using the same catalyst produced in a different manner. Union Carbide Chemicals & Plastics Technology Corp. v. Shell Oil Co., Case Nos. 02-1001, -1020 (Fed. Cir. Sept. 20, 2002).
This case involves technology to improve silver catalysts for the production of ethylene oxide, a chemical used to make substances such as polyester fiber, resin and film and is produced when ethylene is reacted with oxygen. The catalyst may be improved by the addition of other metals to increase the efficiency of the reaction and to prolong the catalyst’s duration. The claim recited that certain constituents in the catalyst are "characterizable by [a recited] efficiency equation."
