| abstract |
The invention relates to novel optical recording materials that comprise specific and in some cases novel diketone enamines or metal chelates thereof and that have excellent recording and playback quality especially at a wavelength of 350-500 nm. The invention accordingly relates to an optical recording medium comprising a substrate, a recording layer and optionally a reflecting layer, wherein the recording layer comprises a compound of formula (I), wherein M is hydrogen, aluminium or, preferably, a transition metal, which may in addition be coordinated with one or more further ligands and/or, for balancing out an excess charge, where applicable, may have an electrostatic interaction with one or more further ions inside or outside the coordination sphere, but M in formulae (Ib) and (Ic) is not hydrogen, Q is C—H, N or C—R 6 , it being possible for the stereochemistry of the C=Q double bond to be either E or Z. For the exact definitions of R 1 to R 6 reference should be made to the description. Also claimed are the novel compounds, especially tetracoordinated chelates, and a process for the preparation thereof. |