| 摘要 |
PURPOSE:To clearly discriminate the written sections from non-written sections by appearance by providing a heat sensitive layer adapted to vary in the coloring by a laser beam. CONSTITUTION:A reflection layer 2 arranged on the top surface of a substrate 1 made up of glass or the like is made by even sputtering or evaporation of aluminum, silver or the like. A thermosensitive layer 5 is so arranged on the top surface of the reflection layer 2 as to vary in the coloring with a laser beam when a writing is done. The thermosensitive film herein used shall meet the requiremmnt of varying the coloring by heat of a laser beam used for writing put not by heat of light in the daily life while never affecting the reduction. When a writing is done by a leser beam, for example, Co(CH3COO)2 varies from pink to purple at the coloring temperature of 82 deg.C. A recording medium layer 3 made of tellurium, chalcogenite or the like is provided on the top surface of the thermosensitive layer 2 and a protective layer 4 made of silicon oxide or the like is arranged on the top surface thereof 3. |
