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EP 4 172 127 A1

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(43) Date of publication: 03.05.2023 Bulletin 2023/18 (21) Application number: 21739758.7 (22) Date of filing: 25.06.2021

(51) International Patent Classification (IPC):  C04B 26/04(2006.01) C04B 18/02(2006.01) C04B 111/54(2006.01) C04B 18/20(2006.01) B29C 67/24(2006.01) C04B 26/06(2006.01) C04B 40/00(2006.01) C04B 16/04(2006.01) C04B 40/02(2006.01) (52) Cooperative Patent Classification (CPC): C04B 2111/54; C04B 26/04; C04B 26/06; C04B 18/022; C04B 40/0071; C04B 40/0082; C04B 40/0085; C04B 18/20; C04B 16/04; C04B 40/0259; C04B 40/0263; B29C 67/242; Y02W 30/91   C-Sets: C04B 26/04, C04B 14/06, C04B 14/305, C04B 16/04, C04B 18/022, C04B 18/20, C04B 20/0096; C04B 26/06, C04B 14/06, C04B 14/305, C04B 16/04, C04B 18/022, C04B 18/20, C04B 20/0096; C04B 18/022, C04B 14/305; (86) International application number: PCT/GB2021/051626 (87) International publication number: WO 2021/260393 (30.12.2021 Gazette 2021/52)

(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: 26.06.2020 GB 202009794 (71) Applicant: Perspex International Limited Darwen BB3 1AT (GB)	(72) Inventors: APSEY, Glenn Christopher Darwen BB3 1AT (GB) FISHER, Adam Darwen BB3 1AT (GB) (74) Representative: Appleyard Lees IP LLP  15 Clare Road Halifax HX1 2HY Halifax HX1 2HY (GB)