| 摘要 |
PURPOSE:To obtain an information-recording medium capable of recording and erasing information, by laminating, or incorporating in mixture, a light- absorbing material comprising a croconic methine compound of a specified formula. CONSTITUTION:A croconic methine compound of formula I or II is laminated or incorporated as a light-absorbing material to produce an information- recording medium capable of recording and erasing information. In the formulas, each of R1 and R2 is a substd. or unsubstd. alkyl, cycloalkyl, allyl, substd. or unsubstd. aralkyl or substd. or unsubstd. aryl, each of Z1 and Z2 is a non-metallic atomic group necessary for completing a substd. or unsubstd. heterocyclic ring, each of m and n is 0 or 1, M<+> is a cation and X<-> is an anion. The information- recording medium is capable of recording and erasing information at high speed and in high density by heating a specified region thereof to a specified temperature. |
