Transparent, UV protective, acid-free, archival & non-toxic, universal acrylic adhesive and medium. Extensively studio-tested on literally every type of paper, plastic, metal, wood and glass. Substantially different than any other wet adhesive, PPA is non-sticky when wet and absolutely non-tacky, when dry. Use PPA for fine art collage, montage, assemblage, decoupage, rubberstamping, scrapbooking, book arts, a dry pigment medium, glazing, or as a finishing coat.