| abstract |
The present invention relates to a novel optical recording material containing a specific and, in some cases, a novel diketone stereoisomer or a metal chelate thereof and having excellent recording and reproduction quality particularly at a wavelength of 350 to 500 nm. The present invention thus provides an optical recording medium comprising a substrate, a recording layer and optionally a reflective layer, wherein the recording layer has the formula (I) [wherein M is hydrogen, aluminum or, preferably, transition. Metal and M may be further coordinated to one or more additional ligands and / or in the coordination sphere where appropriate to balance excess charge. It may have an electrostatic interaction with one or more additional ions, either internal or external, but in formulas (Ib) and (Ic), M is not hydrogen and Q is C—H, N or C—R 6 and can be either E or Z in the stereochemistry of the C═Q double bond. See the detailed description for the exact definitions of R 1 to R 6 . ] It is related with the optical recording medium containing the compound shown by this. Also claimed are novel compounds, particularly tetra-coordinate chelates, and methods for their production. |