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EP 4 466 394 A1

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(43) Date of publication: 27.11.2024 Bulletin 2024/48 (21) Application number: 23702032.6 (22) Date of filing: 18.01.2023

(51) International Patent Classification (IPC):  D01F 2/08(2006.01) C08B 16/00(2006.01) D01F 2/02(2006.01) C08B 1/00(2006.01) D01D 5/06(2006.01) D01F 13/02(2006.01) (52) Cooperative Patent Classification (CPC): D01F 2/08; C08B 16/00; C08B 1/00; D01F 2/02; D01D 5/06; C08B 1/003; D01F 13/02 (86) International application number: PCT/FI2023/050040 (87) International publication number: WO 2023/139310 (27.07.2023 Gazette 2023/30)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA Designated Validation States: KH MA MD TN (30) Priority: 18.01.2022 FI 20225040 (71) Applicant: Metsä Spring Oy 02100 Espoo (FI)	(72) Inventors: NIEMZ, Frank-Günter 07407 Rudolstadt (DE) STURM, Michael 07318 Saalfeld (DE) VON WEYMARN, Niklas 00340 Helsinki (FI) ROSELLI, Annariikka 01630 Vantaa (FI) (74) Representative: Laine IP Oy  Porkkalankatu 24 00180 Helsinki 00180 Helsinki (FI)