olyvinyl butyral and other acetals, polyvinyl chloride, polyvinyl acetate and its hydrolysis products, polyvinyl chloride-acetate copolymer and the like; the acrylic resins, such as, polymers and copolymers of methyl acrylate, acrylamide, methylolacrylamide, acrylonitrile and the like; the polyoleiins such as polyethylene, polypropylene and the like; polyesters and unsaturatedmodified polyester re