| 摘要 |
PURPOSE:To obtain a near infrared absorber excellent in light resistance and heat resistance and rich in solubility in various solvents and compatibility with various resins, by using a specified metal-complex salt compound. CONSTITUTION:A near infrared absorber using a metal-complex salt compound of general formula (1) can be effectively used as a main material of a recording element of an optical disk, a medium or a member for shielding light of a wavelength in a visible light range or near infrared region, namely, a filter. The compound can be obtained in a high yield by converting diazo components of general formulas (2) into a diazo compound by the usual method, coupling the diazo compound with azo components of general formulas (3) by the usual method to produce monoazo compounds of general formulas (4), (5), treating the monoazo compounds with an iron salt in water or an organic solvent and, optionally, subjecting the resultant product to a salt-forming treatment with an aliphatic amine (inclusive of substd. aliphatic amine) or an alicyclic amine. |
