must be marked printed time stamped or coded in such a manner as to be legible and readable the u201c release material u201d may be composed of materials such as parchment polyester foil paper natural waterleaf polyethylene and any material considered appropriate for use as u201c release material u201d in the roofing industry among the methods suitable for marking printing or coding a u201c release material u201d are included direct printing time stamp bar code reverse printing ink jet spray ultra violet and radiation code isotope the aforesaid marking print or code may be applied to either side of the u201c release material u201d or may be applied directly to the release agent that covers the surface of the u201c release material u201d using an ink or similar material it is beneficial for legibility purposes to use heat resistant ink or similar material on that side of the material contacting the backside asphalt during production of a compositional shingle the ink or similar material should also remain legible when in contact with the asphaltic and non asphaltic sealant type materials used in the production of a compositional shingle the ink or similar material should also remain legible under all production parameters including both packaging.