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(11)

EP 0 491 024 A1

(12)

(43) Date of publication: 24.06.1992 Bulletin 1992/26 (21) Application number: 91912489.0 (22) Date of filing: 03.07.1991

(51) International Patent Classification (IPC):  G01N 31/ 22( . ) G01N 33/ 543( . ) G01N 37/ 00( . ) G01N 33/ 52( . ) G01N 33/ 558( . ) (86) International application number: PCT/GB1991/001079 (87) International publication number: WO 1992/001226 (23.01.1992 Gazette 1992/03)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI NL SE (30) Priority: 05.07.1990 GB 19900014903 (71) Applicants: UNILEVER PLC London EC4P 4BQ (GB) UNILEVER N.V. NL-3013 AL Rotterdam (NL)

(72) Inventors: CARR, Anthony Hugh 2 Church Road Bedfordshire MK43 7QB (GB) MAY, Keith 33 Molivers Lane Bedfordshire MK43 8JT (GB) MUNDILL, Paul Henry Charles 4 Brookside Wellingborough Northamptonshire NN9 6PW (GB) PRIOR, Michael Evans 330 Newton Road Northants NN15 0SY (GB) (74) Representative: Butler, David John, et al  Unilever PLC Patent Division Colworth House Sharnbrook Bedford MK44 1LQ Bedford MK44 1LQ (GB)