| abstract |
To provide a near-IR absorption compound free from antimony or arsenic and excellent in stability, especially, in heat resistance, light fastness, and moisture-and-heat resistance and also an IR absorption filter, an optical information recording medium, and a resin composition excellent in durability by using the near-IR absorption compound. n nThe near-IR absorption compound is a diimmonium compound having the following structure and the resin composition contains the diimmonium compound: n n n(wherein R 1 to R 8 independently denote hydrogen atom or an optionally substituted aliphatic hydrocarbon group; R 9 and R 10 independently denote an aliphatic hydrocarbon group optionally containing a halogen atom; and rings A and B may further have substituent groups.). |