The label has a primary film (10) and a secondary film (20) that are provided with top surfaces (11,21) and bottom surfaces (12,22) respectively. An adhesive (40) is coated on top surface of primary film. The bottom surface of primary film is securely bonded to the top surface of the secondary film, in order to form a film composite. The film composite is provided with punched cut having an open line contour with two end points (A,B), so that a strip-like flap (50) is bonded to the rest of the film composite along an imaginary line between the two end points. Independent claims are included for the following: (1) label roll； and (2) method for attaching label to infusion bag.
