(19)

(11)

EP 0 081 487 A1

(12)

(43) Date of publication: 22.06.1983 Bulletin 1983/25 (21) Application number: 81901985.0 (22) Date of filing: 22.06.1981

(51) International Patent Classification (IPC):  C01B 31/ 00( . ) C01B 31/ 06( . ) C01B 31/ 02( . ) (86) International application number: PCT/US1981/000866 (87) International publication number: WO 1983/000038 (06.01.1983 Gazette 1983/01)

(84) Designated Contracting States: DE FR GB (71) Applicants: FRENCH, Frederic A. Portola Valley, CA 94025 (US) FRENCH, Douglas A. Portola Valley, CA 94025 (US)	(72) Inventors: FRENCH, Frederic A. Portola Valley, CA 94025 (US) FRENCH, Douglas A. Portola Valley, CA 94025 (US) (74) Representative: Reinländer & Bernhardt Patentanwälte  Orthstrasse 12 D-8000 München 60 D-8000 München 60 (DE)