(19)

(11)

EP 0 482 058 A1

(12)

(43) Date of publication: 29.04.1992 Bulletin 1992/18 (21) Application number: 90910845.0 (22) Date of filing: 13.07.1990

(51) International Patent Classification (IPC):  B29C 55/ 00( . ) B29D 99/ 00( . ) B32B 3/ 28( . ) B29K 27/ 18( . ) B29C 55/ 30( . ) B31D 3/ 00( . ) B29K 23/ 00( . ) (86) International application number: PCT/GB1990/001081 (87) International publication number: WO 1991/001210 (07.02.1991 Gazette 1991/04)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB IT LI NL SE (30) Priority: 14.07.1989 GB 19890016231 (71) Applicant: NATIONAL RESEARCH DEVELOPMENT CORPORATION London SE1 6BU (GB)	(72) Inventors: EVANS, Kenneth Ernest Warrington, Cheshire WA4 2EN (GB) AINSWORTH, Kim Lesley Liverpool L6 5BJ (GB) (74) Representative: Hamilton, Raymond  Patents Department British Technology Group Ltd 101 Newington Causeway London SE1 6BU London SE1 6BU (GB)