FILM FOR KEYPAD, KEYPAD, AND KEY SHEET

摘要

A film for keypads is provided which is excellent in nontackiness, handleability, heat resistance, and dimensional-accuracy stability. Even when subjected especially to a heat treatment, the film causes no problems such as failures, e.g., warpage and shrinkage, and blocking with another film. This film enables a final product to be reduced in weight and size, and gives a keypad or key sheet which can be produced through simplified steps. Also provided are a keypad and a key sheet both employing the film. The film for keypads is made only of a thermoplastic polyurethane obtained by reacting a high-molecular polyol, an organic polyisocyanate, and a chain extender or is made of a thermoplastic polyurethane composition comprising the thermoplastic polyurethane as the main ingredient. This film has a tensile stress at 100% elongation as measured at 23°C (M100) of 18 MPa or higher.