"More concretely, materials suitable for forming the adhesive layer 53 are cellulose derivatives including ethyl cellulose and cellulose acetate propionate, styrene resins including polystyrene resins and methyl styrene resins, acrylic resins including polyethyl methacrylate resins, polymethyl methacrylate resins and polyacrylic ethyl resins, vinyl resins including polyvinyl chloride resins, polyvi" . . . . .