| abstract |
The invention relates to an optical recording medium comprising a substrate, a reflecting layer and a recording layer, wherein the recording layer comprises a compound of formula [L1Mr-4L2]o [Am-]p [Zn+]q (I), [L1Mr-3L3]o [Am-]p [Zn+]q (II) or [L3Mr-2L4]o [Am-]p [Zn+]q (III), or where applicable a mesomeric or tautomeric form thereof wherein L1 and L2 are each independently of the other, and L3 and L4 are each independently of the other, wherein, Q1 is CR1 or N, Q2 is O, S, NR10 or Q5=Q8, Q3 is CR3 or N, Q4 is O, S, NR10 or Q7=Q8, Q5 is CR5 or N, Q6 is CR6 or N, Q7 is CR7 or N, Q8 is CR8 or N, and Q9 is O, S, NR10 or Q6=Q8; Mr is a transition metal cation having r positive charges, Am- is an inorganic, organic or organometallic anion, or is a mixture thereof; Zn+ is a proton, a metal, ammonium or phosphonium cation, a positively charged organic chromophore, or a mixture thereof; R2 is OR9, SR9, NR10R15, NR10COR11, NR10COOR9, NR10CONR12R13 or NR10CN; each R9, independently of any other R9, is R15, COR15, COOR15, CONR12R13, CN or a negative charge, preferably H or a negative charge; and R10 may be inter alia a delocalisable negative charge; but with the exception of, in combination with pentacyclic rhodamines according to WO-03/098617 and WO-03/098618. The invention relates also to novel compounds of formulae (II) and (III) wherein R9 or R10 is a negative charge. |