One of the main reasons photos and other papers turn yellow, even when protected in a frame, is because they’re exposed to naturally occurring acidic materials. Paper-based materials contain lignin (a chemical in wood pulp) which can produce acid as it ages and deteriorates. This is what causes photos, documents, and artwork exposed to or produced on lignin-containing materials to discolor. Another common cause of discoloration is exposure to UV light. Order picture frame from Wilsonmoulding, a museum quality framer who tries their best to protect your artwork from yellowing.
