Dithiolate metal complex compound, production method of the same, and optical information recording medium comprising the same

A method of producing a dithiolate metal complex compound consisting of an anion and a counter cation, having formula:

• ##STR34## wherein each R individually represents an alkyl group having 1 to 6 carbon atoms, a halogen, a halogenated alkyl group having 1 to 6 carbon atoms, an amino group which may be substituted with 1 or 2 alkyl groups each having independently 1 to 4 carbon atoms, or a trifluoromethyl group,
• M represents a transition metal selected from the group consisting of Ni, Pd, Pt, Co, Cu and Mn,
• n is an integer of 0 to 4, and
• A represents the counter cation of the complex compound, comprising the step of:
• reacting (a) a neutral dithiolate metal complex having formula or an onium salt of the monoanion thereof:
• ##STR35## wherein each R individually represents an alkyl group having 1 to 6 carbon atoms, a halogen, a halogenated alkyl group having 1 to 6 carbon atoms, an amino group which may be substituted with 1 or 2 alkyl groups each having independently 1 to 4 carbon atoms, or a trifluoromethyl group,
• M represents a transition metal selected from the group consisting of Ni, Pd, Pt, Co, Cu and Mn, and
• n is an integer of 0 to 4, with (b) bis-(onium) salt of a dicyanoethylenedithiolate metal complex having formula:
• ##STR36## wherein M represents a transition metal selected from the group consisting of Ni, Pd, Pt, Co, Cu and Mn, and
• A represents the counter cation of the complex compound.

An optical information recording medium comprising:

• a substrate, and
• a recording layer formed on said substrate, comprising a polymethine dye and a dithiolate metal complex compound having formula:
• ##STR51## wherein each R' individually represents an alkyl group having 1 to 6 carbon atoms, a halogen, a halogenated alkyl group having 1 to 6 carbon atoms, an amino group which may be substituted with 1 or 2 alkyl groups each having independently 1 to 4 carbon atoms, a cyano group, a nitro group, or a trifluoromethyl group,
• M represents a transition metal selected from the group consisting of Ni, Pd, Pt, Co, Cu and Mn,
• n is an integer of 0 to 4, and
• A represents the counter cation of the complex compound.