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.