| 摘要 |
The object is to ensure the record reproduction property and the data storage reliability in a write-once type two-layered recording medium. A organic dye represented by the general formula [Chemical formula 3] and an organic dye represented by the general formula [Chemical formula 4] are added to the second recording layer from the side to be irradiated with record reproduction light in the recording medium, whereby the recording medium is imparted with ensured durability. [Chemical formula 3] wherein R1 and R2 independently represent an alkyl group having 1 to 4 carbon atoms; Y1 and Y2 independently represent an organic group; and X represents ClO4, BF4, PF6 or SbF6; and [Chemical formula 4] wherein R1 and R4 independently represent an alkyl group having 1 to 4 carbon atoms; R2 and R3 independently represent an alkyl group having 1 to 4 carbon atoms or together form a 3-to 6-membered cyclic ring; Y1 nd Y2 independently represent an organic group; and X represents ClO4, BF4, PF6 or SbF6. |
