(19)

(11)

EP 4 522 821 A1

(12)

(43) Date of publication: 19.03.2025 Bulletin 2025/12 (21) Application number: 23731337.4 (22) Date of filing: 10.05.2023

(51) International Patent Classification (IPC):  E04B 1/76(2006.01) E04F 13/08(2006.01) E04B 1/94(2006.01) (52) Cooperative Patent Classification (CPC): E04B 1/762; E04B 1/942; E04F 13/0875 (86) International application number: PCT/GB2023/051222 (87) International publication number: WO 2023/218186 (16.11.2023 Gazette 2023/46)

(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: 10.05.2022 GB 202206789 (71) Applicant: Intumescent Systems Limited Barfrestone Dover Kent CT15 7JG (GB)	(72) Inventor: WARD, Derek Dover Kent CT15 7JG (GB) (74) Representative: Fry, David John  Agile IP LLP Airport House Purley Way Croydon, Greater London CR0 0XZ Croydon, Greater London CR0 0XZ (GB)