Fredrix Archival Board is constructed with the highest quality, non-acidic archival materials available.The tempered hardboard core will not warp or rot.Mounted with acid-free adhesive, the painting surface is medium texture, 100% cotton duck.Grounded with a proprietary, two coat, acid-free formula of acrylic-titanium gesso primer, these canvas boards are truly archival.They are suitable for oil or acrylic painting.