Azo-metal chelate dye and optical recording medium
View Patent ↗The azo-metal chelate dye of the present invention is formed, for example, from zinc (divalent) as a center metal ion and an azo compound bonded with a coupler component having an amino group and a fluorine-substituted alkylsulfonylamino group subjected to condensed ring-formation to have a 1,3,4-thiazole ring as a diazo component.
1. An optical recording medium for recording and reading with a semiconductor laser light of 300 nm to 700 nm, which has a recording layer containing an azo-metal chelate dye formed from a ligand having active hydrogen in X 1 or X 2 eliminated from an azo compound of the following formula (III) and Zn 2+ ion,
wherein in the above formula (III), R 21 is a hydrogen atom, a halogen atom or an ester group expressed by CO 2 R 23 in which R 23 is a linear or branched alkyl group or a cycloalkyl group; R 22 is a linear or branched alkyl group which may have a substituent; one of X 1 and X 2 is a NHSO 2 Y group in which Y is a linear or branched alkyl group substituted with at least 2 fluorine atoms, and the other is a hydrogen atom; R 24 and R 25 are respectively independently a hydrogen atom or a linear or branched alkyl group which may have a substituent; R 26 , R 27 , R 28 and R 29 are respectively independently a hydrogen atom or a C 1 -C 2 alkyl group which may have a substituent; and the NHSO 2 Y group forms a NSO 2 Y − (negative) group by eliminating H + , and an azo compound of the above formula (III) forms a coordinate bond with a metal ion.
2. The optical recording medium according to claim 1 , wherein a dye layer has a retention ratio of light absorbance persistent values of at most 20% as measured before and after being subjected to a light resistance test of Wool scale 5 Class under light irradiation conditions of ISO-105-B02.
3. A method for recording on and reading an optical recording medium, comprising applying a semiconductor laser light of 300 nm to 700 nm to the optical recording medium of claim 1 .
4. The optical recording medium according to claim 1 , wherein R 21 is hydrogen or halogen.
5. The optical recording medium according to claim 1 , wherein Y is trifluoromethyl or 2,2,2-trifluoroethyl.
6. The optical recording medium according to claim 1 , wherein R 24 and R 25 are independently hydrogen, methyl, ethyl or methoxy.
7. The optical recording medium according to claim 1 , wherein R 22 is unsubstituted C 1 -C 6 linear alkyl or C 3 -C 8 branched alkyl.
8. The optical recording medium according to claim 1 , wherein R 26 , R 27 , R 28 and R 29 are hydrogen.
9. In a method of making an optical recording medium comprising a recording layer, the improvement comprising forming the recording layer containing an azo-metal chelate dye formed from a ligand having active hydrogen in X 1 or X 2 eliminated from an azo compound of the following formula (III) and Zn 2+ ion,
wherein in the above formula (III), R 21 is a hydrogen atom, a halogen atom or an ester group expressed by CO 2 R 23 in which R 23 is a linear or branched alkyl group or a cycloalkyl group; R 22 is a linear or branched alkyl group which may have a substituent; one of X 1 and X 2 is a NHSO 2 Y group in which Y is a linear or branched alkyl group substituted with at least 2 fluorine atoms, and the other is a hydrogen atom; R 24 and R 25 are respectively independently a hydrogen atom or a linear or branched alkyl group which may have a substituent; R 26 , R 27 , R 28 and R 29 are respectively independently a hydrogen atom or a C 1 -C 2 alkyl group which may have a substituent; and the NHSO 2 Y group forms a NSO 2 Y − (negative) group by eliminating H + , and an azo compound of the above formula (III) forms a coordinate bond with a metal ion.