Patent ID: 6762008
Filing Date: 2004-07-13
Classification: C09B,G11B,Y10S

Abstract:
An optical recording medium comprising a substrate, and a recording layer formed thereon comprising a formazan chelate compound selected from the group consisting of:a compound represented by formula (I): wherein Z represents a group that forms a polyheterocyclic ring with a carbon atom and a nitrogen atom that are bounded thereto, said polyheterocyclic ring being selected from the group consisting of a pyridazine ring, a pyrimidine ring and a triazine ring, A is an alkyl group, an aralkyl group, an aryl group, or cyclohexyl group, B is an aryl group, M represents a bivalent metal atom, and n represents the coordination number of formazan ligands;a compound represented by formula (II): wherein Z represents a group that forms a polyheterocyclic ring with a carbon atom and a nitrogen atom that are bounded thereto, said polyheterocyclic ring being selected from the group consisting of a pyridazine ring, a pyrimidine ring and a triazine ring, Aâ€² represents a five-membered ring or six-membered ring, or a group that constitutes the heterocyclic ring, Bâ€² is an aryl group or an alkyl group, M represents a bivalent metal atom, and n represents the coordination number of formazan ligands; anda compound represented by formula (III): wherein Z1 and Z2 are each a group that forms a heterocyclic ring with a carbon atom and a nitrogen atom that are bounded thereto, A1 and A2 are each an alkyl group, an aralkyl group, an aryl group, or cyclohexyl group, B1 and B2 are each an aryl group, p is an integer of 0 or 1, and when p is 1, X is methylene group, or sulfone group, and M represents a bivalent metal atom.