聚氯乙烯
An international standard, ISO 18902, provides specific guidelines on materials that are safe for scrapbooking through its requirements for albums, framing, and storage materials. ISO 18902 includes requirements for photo-safety and a specific pH range for acid-free materials. ISO 18902 prohibits the use of harmful materials, including Polyvinyl chloride (PVC) and Cellulose nitrate.