| 摘要 |
PURPOSE:To repeat optional recording and erasion of 2-colors high in contrast, by subjecting a 2-color recording medium consisting of a mixture of viologen compound and a high molecular weight alcohol to light irradiation and heating by a specified method. CONSTITUTION:A thin layer 3 made by dispersing a viologen compound represented by the formula shown (R is methyl, ethyl, benzyl, or the like, and X is halogen, BF4, or the like anion forming atomic group) into a polymeric alcohol, such as polyvinyl alcohol is formed on a substrate 5, 1 provided with a thin film resistor, and a protective film 4 is provided on the layer 3 to form a 2-color developing medium. Said medium develops blue on light irradiation, turns purple green on being heated to 80-150 deg.C, and perfectly decolored by heating it to 160-200 deg.C. Said processes can be repeated. A polymer viologen may be used in place of the mixture of viologen compound and polymer alcohol. |
