I work in x-rays as an art form and have used x-ray film for many years strictly for x-ray purposes. Mammography film is single coated on one side and general purpose blue or green sensitivity x-ray film is coated on both sides of the film base but not double coated on either side. To my knowledge there is no double coating on any x-ray film on a single side only. X-ray film is generally very grainy and if you enlarge you may get a secondary image from the double sided emulsion.