| abstract |
The invention, wherein the recording track comprises a compound of formula or a mesomeric or tautomeric form thereof and are each independently of the other or; is or C2-C8heteroaryl unsubstituted or mono-or poly-substituted by R47, R48, R49, and/or R50; Q1 and Q6 are each independently of the other O or S; Q2 and Q4 are each independently of the other O, S or NR51; Q3 is N or CR52; Q5 is N, or is CR14 when Q4 is O or S; Q7 is O, S, CR22R23 or NR35; Q8 and Q10 are each independently of the other CR53R54, O, S or NR55; Q9 is CR43 or N; Q11 is CR56 or N; Q12, Q14 and Q16 are each independently of the other CR57R58, O, S or NR51; Q13 and Q15 are each independently of the other CR59 or N. The structures of the cations and the substituents are defined in the description. The invention also pertains to the use of compounds of the formula (I) in optical recording with a blue laser as well as to optical recording processes wherein pits of either lower or higher reflecticity are written on a track comprising compounds of the formula (I). Hence, the invention finally also relates to an optical recording medium comprising a recording dye which is bathochromic as compared with the laser wavelength, on which medium pits of lower reflectivity are written on a higher reflectivity track. |