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EP 3 746 410 A1

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(43) Date of publication: 09.12.2020 Bulletin 2020/50 (21) Application number: 19746958.8 (22) Date of filing: 29.01.2019

(51) International Patent Classification (IPC):  C03B 5/187(2006.01) C03C 3/093(2006.01) C03B 5/42(2006.01) C03B 5/235(2006.01) (86) International application number: PCT/KR2019/001227 (87) International publication number: WO 2019/151747 (08.08.2019 Gazette 2019/32)

(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: 30.01.2018 KR 20180011606 (71) Applicant: Corning Incorporated Corning, New York 14831 (US)

(72) Inventors: KIM, Dong Bin Chung-nam Cheon-ahn, Seo-buk gu, 31166 (KR) SHIN, Dong-won Asan-City, Chungnam-do, 31579 (KR) KIM, Euiho Asan-si Chungcheongnam-do 31495 (KR) PARK, Hyungjin Cheonan-si Chungcheongnam-do 31156 (KR) KWON, Yong-kyu Asan-si, Chungcheongnam-do 31455 (KR) KIM, JiHyun Seoul 05267 (KR) EOM, Jucheon Cheonan-si Chungcheongnam-do 31158 (KR) MUN, Chonsu Asan-si Chungcheongnam-do 31457 (KR) KIM, Dongwon Asan-si Chungcheongnam-do 31448 (KR) (74) Representative: Elkington and Fife LLP  Prospect House 8 Pembroke Road Sevenoaks, Kent TN13 1XR Sevenoaks, Kent TN13 1XR (GB)