(19)

(11)

EP 0 726 930 A1

(12)

(43) Date of publication: 21.08.1996 Bulletin 1996/34 (21) Application number: 94931656.0 (22) Date of filing: 04.11.1994

(51) International Patent Classification (IPC):  C10M 169/ 04( . ) F04B 39/ 02( . ) C10M 171/ 00( . ) F25B 31/ 00( . ) (86) International application number: PCT/GB1994/002421 (87) International publication number: WO 1995/012649 (11.05.1995 Gazette 1995/20)

(84) Designated Contracting States: BE CH DE DK ES FR GB IT LI NL SE (30) Priority: 06.11.1993 GB 19930022887 27.07.1994 GB 19940015118 (71) Applicant: CASTROL LIMITED Swindon Wiltshire SN3 1RE (GB)

(72) Inventors: GREIG, Barry Dennis Reading, Berkshire RG4 7HS (GB) SMITH, Andrew Michael Wallingford, Oxfordshire OX10 6NR (GB) SWALLOW, Andrew Reading, Berkshire RG4 8QF (GB) O'BRIEN, Margaret Mary Reading, Berkshire RG5 4JD (GB) (74) Representative: Eyles, Winifred Joyce  Burmah Castrol Group Patents Department Burmah Castrol House Pipers Way Swindon, Wiltshire SN3 1RE Swindon, Wiltshire SN3 1RE (GB)