Infrared absorbent comprising a metal complex compound containing two thiolato bidentate ligands

摘要

The present invention relates to a metal complex compound useful in an infrared absorbent prepared by coordinating two bidentate ligands of the following formula (iii): ##STR1## wherein R.sup.1 and R. sup.2 each independently represents a hydrogen atom, a cyano group, or a substituted or unsubstituted alkyl, aryl or heterocyclic group, which may be the same or different.PPThe present invention is further directed to an infrared absorbing composition comprising a metal complex compound prepared by coordinating two bidentate ligands of formula (iii) above to a center metal and neutralizing a complex ion with a cation.P PThe present invention is also directed to an infrared absorbing article which comprises a metal complex compound prepared by coordinating two bidentate ligands of formula (iii) above to a center metal and neutralizing such a complex with a phosphonium cation.