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(11)

EP 2 144 850 A2

(12)

(88) Date of publication A3: 31.12.2008 (43) Date of publication: 20.01.2010 Bulletin 2010/03 (21) Application number: 07857933.1 (22) Date of filing: 20.12.2007

(51) International Patent Classification (IPC):  C01B 33/40(2006.01) D21H 21/02(2006.01) (86) International application number: PCT/EP2007/064312 (87) International publication number: WO 2008/077877 (03.07.2008 Gazette 2008/27)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR Designated Extension States: AL BA HR MK RS (30) Priority: 22.12.2006 DE 102006061046 (71) Applicant: Omya Development AG 4665 Oftringen (CH)	(72) Inventors: BURI, Matthias 4852 Rothrist (CH) KARTH, Beat 3363 Oberoenz (CH) GANTENBEIN, Daniel 4145 Gempen (CH) GANE, A.C. Patrick 4852 Rothrist (CH) (74) Representative: Maiwald Patentanwalts GmbH  Elisenhof Elisenstrasse 3 80335 München 80335 München (DE)