... wax. They are available in all photographic sizes. Properties:Glassine envelopes are made from pure pine wood cellulose which is 100 ... , chlorine and acid free and does not contain chemical softeners.Envelopes do not have an adhesive seal, but come with flap ... are ideal for the safe protection of stamps,blocks,sheetlets,envelopes,Fdc's,postcards,telephone cards,bank notes,photos and negatives ...