Azo dyes, compositions for anisotropic dye films using them, anisotropic dye films and polarizing elements
View Patent ↗To provide a dye capable of forming an anisotropic dye film showing high dichroism and having a high degree of molecular orientation, a composition containing the dye, an anisotropic dye film using the dye and a polarizing element. A trisazo dye, of which the free acid form is represented by the following formula (1), wherein at least one of B 1 and D 1 has at least one substituent as defined by the following Q1, a dye composition for an anisotropic dye film containing the dye, an anisotropic dye film and a polarizing element using the anisotropic dye film: Q1: an alkyl group or alkoxy group substituted by a hydrogen bond-forming group: wherein A 1 is a phenyl group or a naphthyl group, each of B 1 and D 1 is a phenylene group or a naphthylene group, X 1 is an amino group which may be substituted or a hydroxyl group, and m is 0 or 1.
1. A trisazo dye, of which the free acid form is represented by the following formula (1), wherein at least one of the groups represented by B 1 and D 1 has at least one substituent as defined by Q1, which is an alkyl group or alkoxy group substituted by a hydrogen bond-forming group:
wherein A 1 is a phenyl group or naphthyl group which may be substituted, each of B 1 and D 1 which are independent of each other, is a phenylene group or naphthylene group which may be substituted, and may have a substituent other than Q1, X 1 is an amino group which may be substituted or a hydroxyl group, and is located at the 6- or 7-position on the terminal naphthyl group, and m is 0 or 1, and
wherein at least one of the following (1), (2) and (3) applies:
(1) in the formula (1), each of B 1 and D 1 which are independent of each other, is a group represented by the following formula (a) or (b):
wherein each of Q3 and Q4 which are independent of each other, is a substituent as defined by the above Q1, p is 1 or 2, and n is 0 or 1,
(2) in the above formula (1), A 1 is a group represented by the following formula (c):
wherein Y 1 is a sulfo group, a carboxy group or a phosphoric acid group, Z 1 is a halogen atom, a hydroxyl group, a nitro group, a cyano group, an amino group which may be substituted, a C 1-4 alkyl group which may be substituted, a C 1-4 alkoxy group which may be substituted, a sulfo group or a carboxy group, and q is 0 or 1, and
(3) X 1 is a hydroxyl group.
2. The trisazo dye according to claim 1 , wherein in formula (1), Q1 is an alkyl group or alkoxy group substituted by a —OH group, a —COOH group, a —NR 1 R 2 group, a —SO 2 NR 3 R 4 group or a
—CONR 5 R 6 group, wherein each of R 1 to R 6 which are independent of one another, is a hydrogen atom or a C 1-6 alkyl group which may be substituted.
3. The trisazo dye according to claim 1 , wherein in formula (1), each of B 1 and D 1 which are independent of each other, is a group represented by the following formula (a) or (b):
wherein each of Q3 and Q4 which are independent of each other, is a substituent as defined by Q1, p is 1 or 2, and n is 0 or 1.
4. The trisazo dye according to claim 1 , wherein in formula (1), A 1 is a group represented by the following formula (c):
wherein Y 1 is a sulfo group, a carboxy group or a phosphoric acid group, Z 1 is a halogen atom, a hydroxyl group, a nitro group, a cyano group, an amino group which may be substituted, a C 1-4 alkyl group which may be substituted, a C 1-4 alkoxy group which may be substituted, a sulfo group or a carboxy group, and q is 0 or 1.
5. A composition for an anisotropic dye film, which comprises the trisazo dye as defined in claim 1 and a solvent.
6. An anisotropic dye film, which comprises the trisazo dye as defined in claim 1 .
7. A polarizing element comprising the anisotropic dye film as defined in claim 6 .
8. The trisazo dye according to claim 1 , wherein X 1 is an amino group which may be substituted.
9. The trisazo dye according to claim 1 , wherein X 1 is a hydroxyl group.