| 摘要 |
PROBLEM TO BE SOLVED: To upgrade recording and reproducing with a laser beam selected from wavelengths of a specific range by incorporating a compound having a tautomerizable structure represented by the specific formula in a recording layer. SOLUTION: A recording layer is provided on a base plate, and a compound represented by the formula is contained, wherein R1, R2, R3, R4, R5, R6, R7 and R8 are each a group having good processability by coating on a polycarbonate, aryl, epoxy or polyolefin base plate and are selectively used. Then, as a substituted or unsubstituted alkyl group, an alkyl group substituted by a substituent selected from the group consisting of a linear, branched or ring-like unsubstituted alkyl group, a halogen atom, a hydroxy group, a cyano group, a heterocyclic group and the like is used. Further, the compound represented by the formula may have a tautomerizable structure or a tautomerism. Thus, recording and reproducing with a laser having a wavelength of 400 to 500 nm can be conducted. |
