Our standard archival board is not conservation grade (it is not lignin-free / certified according to DIN ISO 16245 Type A), but only DIN ISO 16245 Type B, and should not be used in direct contact with the documents to be protected without additional inner packaging. Our Eterno Board is lignin-free and DIN ISO 16245 Type A (https://schmedt.com/eterno-board-sheet-stock-acid-free-solid-board/20056020).