Lineco Light Gray Acid-Free Frame Backing Paper. Use this attractive light gray paper to add value and differentiate the quality of framed artwork. This acid-free buffered paper won't harm the art and won't puncture like every day brown or black kraft paper. Lineco frame backing papers are acid-free and buffered with 3% calcium carbonate to protect the artwork. Moderate porosity allows the frame package to breathe and the standard weight paper cuts cleanly and is easily handled.