| 摘要 |
PROBLEM TO BE SOLVED: To provide a near-infrared-absorbing compound fairly soluble in methyl ethyl ketone (MEK) and to provide a near-infrared-absorbing filter made from the near-infrared-absorbing compound. SOLUTION: Provided are a diimmonium compound represented by formula (1) and a near-infrared-absorbing filter made from the compound. In formula (1), R<SB>1</SB>to R<SB>8</SB>are each a 1 to 8C linear alkyl group which may have branched alkyl groups or substituents, provided that at least one of them is a branched alkyl group. COPYRIGHT: (C)2007,JPO&INPIT |
