| 摘要 |
PURPOSE:To obtain excellent record image even when a plain paper with surface having low smoothness is used, by providing an ink sheet made of a base material having fine irregularity coated with thermally expanding body and ink, and a heating means for transferring the ink. CONSTITUTION:A fine irregularity 22 consists of a number of fine irregularities formed on a base material 21. The irregularities having small diameters are formed on a heat generating body 25 (1 dot) of a thermal head 8. When the fine irregularity 22 is formed, size and depth which can maintain mechanical and thermal strength of the base material 21 are necessary. That is, circular holes having contour of 30mum and depth of 2.5mum are formed at a pitch of 50mum. The recessed parts of the fine irregularity 22 are coated with a thermal expansion medium 23. As the volume of the thermal it expansion medium 23 expands thermally due to the heat of a heating means, a thermal expansion medium whose specific heat or heat of fusion is equal to or lower than that of an ink binder material is used. |
