(19)

(11)

EP 4 085 033 A1

(12)

(43) Date of publication: 09.11.2022 Bulletin 2022/45 (21) Application number: 20909139.6 (22) Date of filing: 29.12.2020

(51) International Patent Classification (IPC):  C03C 3/087(2006.01) C03C 3/097(2006.01) C03C 3/091(2006.01) C03C 13/00(2006.01) (52) Cooperative Patent Classification (CPC): C03C 3/097; C03C 13/00 (86) International application number: PCT/US2020/067269 (87) International publication number: WO 2021/138295 (08.07.2021 Gazette 2021/27)

(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 MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME Designated Validation States: KH MA MD TN (30) Priority: 02.01.2020 US 202016732825 17.02.2020 US 202016792658 (71) Applicant: AGY Holding Corporation Aiken, South Carolina 29801 (US)	(72) Inventors: HAUSRATH, Robert Lurie Aiken, South Carolina 29803 (US) LONGOBARDO, Anthony Vincent Johnston, South Carolina 29832 (US) (74) Representative: Goodman, Simon John Nye  Reddie & Grose LLP The White Chapel Building 10 Whitechapel High Street London E1 8QS London E1 8QS (GB)