(19)

(11)

EP 0 198 849 A1

(12)

(43) Date of publication: 29.10.1986 Bulletin 1986/44 (21) Application number: 85904834.0 (22) Date of filing: 12.09.1985

(51) International Patent Classification (IPC):  C04B 38/ 10( . ) C04B 28/ 06( . ) C04B 28/ 02( . ) (86) International application number: PCT/GB1985/000418 (87) International publication number: WO 1986/001795 (27.03.1986 Gazette 1986/07)

(84) Designated Contracting States: AT BE CH DE FR IT LI LU NL SE (30) Priority: 12.09.1984 GB 19840023076 (71) Applicant: BLUE CIRCLE INDUSTRIES PLC Aldermaston Berkshire RG7 4HP (GB)	(72) Inventor: GARTSHORE, Gavin, Crammond Sevenoaks Kent TN15 8JX (GB) (74) Representative: Grundy, Derek George Ritchie  CARPMAELS & RANSFORD 43, Bloomsbury Square London WC1A 2RA London WC1A 2RA (GB)