An IC tag has a layer of heat sensitive color developing material (I), a
layer of material absorbing light and converting absorbed light into heat
(II) and a protective layer (III) laminated on the surface of the support
successively from the surface, or (II), (I) and (III) laminated on the
surface of the support successively from the surface. This structure
permits recording and erasing invisible information and recording and
erasing visible information, both allowing recording and erasing
information in a non-contact manner. The structure is flexible and can
have a small size.