WO2010038817A1 - 二色性色素組成物、光吸収異方性膜および偏光素子 - Google Patents
二色性色素組成物、光吸収異方性膜および偏光素子 Download PDFInfo
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- WO2010038817A1 WO2010038817A1 PCT/JP2009/067108 JP2009067108W WO2010038817A1 WO 2010038817 A1 WO2010038817 A1 WO 2010038817A1 JP 2009067108 W JP2009067108 W JP 2009067108W WO 2010038817 A1 WO2010038817 A1 WO 2010038817A1
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
- G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
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- C09B31/00—Disazo and polyazo dyes of the type A->B->C, A->B->C->D, or the like, prepared by diazotising and coupling
- C09B31/02—Disazo dyes
- C09B31/04—Disazo dyes from a coupling component "C" containing a directive amino group
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- C09B31/00—Disazo and polyazo dyes of the type A->B->C, A->B->C->D, or the like, prepared by diazotising and coupling
- C09B31/02—Disazo dyes
- C09B31/08—Disazo dyes from a coupling component "C" containing directive hydroxyl and amino groups
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- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09B—ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES, e.g. PIGMENTS; MORDANTS; LAKES
- C09B31/00—Disazo and polyazo dyes of the type A->B->C, A->B->C->D, or the like, prepared by diazotising and coupling
- C09B31/16—Trisazo dyes
- C09B31/18—Trisazo dyes from a coupling component "D" containing a directive amine group
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- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09B—ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES, e.g. PIGMENTS; MORDANTS; LAKES
- C09B31/00—Disazo and polyazo dyes of the type A->B->C, A->B->C->D, or the like, prepared by diazotising and coupling
- C09B31/16—Trisazo dyes
- C09B31/26—Trisazo dyes from other coupling components "D"
- C09B31/28—Heterocyclic compounds
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- C09B31/00—Disazo and polyazo dyes of the type A->B->C, A->B->C->D, or the like, prepared by diazotising and coupling
- C09B31/30—Other polyazo dyes
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- C09B56/02—Azomethine-azo dyes
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- C09B—ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES, e.g. PIGMENTS; MORDANTS; LAKES
- C09B56/00—Azo dyes containing other chromophoric systems
- C09B56/08—Styryl-azo dyes
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- G02—OPTICS
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- G02B5/00—Optical elements other than lenses
- G02B5/20—Filters
- G02B5/22—Absorbing filters
- G02B5/223—Absorbing filters containing organic substances, e.g. dyes, inks or pigments
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3016—Polarising elements involving passive liquid crystal elements
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
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- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K2323/00—Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition
- C09K2323/03—Viewing layer characterised by chemical composition
- C09K2323/031—Polarizer or dye
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2202/00—Materials and properties
- G02F2202/40—Materials having a particular birefringence, retardation
Definitions
- the present invention relates to a dichroic dye composition containing at least one dichroic dye for forming a novel light absorption anisotropic film.
- the present invention also relates to a light-absorbing anisotropic film having the periodic structure in the direction perpendicular to the in-plane alignment axis using the composition.
- the present invention also relates to a polarizing element and a display device using the light absorption anisotropic film.
- LCDs liquid crystal elements
- OLED organic electroluminescence element
- iodine has been widely used as a dichroic substance in these polarizing plates (polarizing elements).
- iodine has a high sublimation property, when used in a polarizing element, its heat resistance and light resistance are not sufficient. Further, the extinction color is deep blue, and it cannot be said to be an ideal achromatic polarizing element over the entire visible spectrum region.
- a polarizing element using an organic dye as a dichroic material has been studied.
- these organic dyes have a problem that only a polarizing element having a dichroism considerably inferior to iodine can be obtained.
- a polarizing element is an important component in an LCD that uses the optical rotation and birefringence of light as a display principle.
- a new polarizing element has been developed for the purpose of improving display performance and the like. .
- One method is to dissolve or adsorb a dichroic organic dye (dichroic dye) in a polymer material such as polyvinyl alcohol in the same way as a polarizing element containing iodine, and film the film in one direction.
- a dichroic organic dye dichroic dye
- a polymer material such as polyvinyl alcohol
- a polarizing element containing iodine a polarizing element containing iodine
- Non-Patent Document 1 a dichroic dye is aligned on a substrate such as glass or a transparent film using intermolecular interaction of organic dye molecules, and a polarizing film (anisotropic dye film) is formed. There is a method of forming.
- a polarizing film anisotropic dye film
- orienting the dichroic dye on the substrate such as glass or transparent film by utilizing the intermolecular interaction of organic dye molecules can be achieved by a wet film forming method.
- the dye used in this dye film is suitable for the process of the wet film formation method in addition to the high dichroism of the dye molecule. It is required to be a pigment.
- the process in the wet film forming method include a method of depositing and orienting a dye on a substrate and a method of controlling the orientation. Therefore, even dyes that can be used in conventional polarizing elements that have undergone the above-described stretching treatment are often not suitable for wet film-forming methods.
- Patent Documents 1 to 3 propose materials suitable for the above process, but these materials have a problem that even if they are suitable for the process, they cannot exhibit high dichroism. .
- Patent Document 4 proposes a dye represented by (chromogen) (SO 3 M) n.
- achromatic color is expressed by combining several kinds of dichroic dyes.
- an anisotropic dye film is obtained by combining several kinds of dichroic dyes in this way, different molecules are mixed. Therefore, the molecular orientation is disturbed, and there is a problem that it is difficult to obtain high dichroism.
- Patent Document 5 describes that a light-absorbing anisotropic film produced by a wet film-forming method is prepared, and is represented by the following structural formula as an example of a dichroic dye that can be used. Things are listed.
- An object of the present invention is to provide a novel light-absorbing anisotropic film having high dichroism and a polarizing element having excellent heat resistance, light resistance, and polarization performance using the light-absorbing anisotropic film. To do. It is another object of the present invention to provide a novel dichroic dye composition capable of realizing a light absorption anisotropic film that functions as a light absorption anisotropic film having heat resistance and light resistance.
- the novel light absorption anisotropic film of the present invention exhibits a diffraction peak derived from a periodic structure in the in-plane direction in X-ray diffraction measurement, and its half-value width is 1.0 mm or less. .
- the present inventors have studied a novel dichroic azo dye in order to realize such a light absorption anisotropic film, and such a dye is represented by the following general formula (I). It was found that a dichroic azo dye having a specific structure takes a highly ordered association state. In addition, a composition containing such a dye is dissolved in an organic solvent, applied onto an alignment film, dried to form a film, and heated, whereby the dichroic azo dye exhibits a higher-order molecular alignment state. That is, it has been found that it is possible to form a dye film having high dichroism and capable of becoming a target light absorption anisotropic film.
- a light absorption difference having at least one kind of dichroic dye characterized by showing a diffraction peak derived from a periodic structure in the in-plane direction in X-ray diffraction measurement and having a half-value width of 1.0 mm or less. Isotropic membrane.
- [4] The light absorption anisotropic film according to any one of [1] to [3], wherein the film thickness is 0.01 to 30 ⁇ m.
- [5] The light-absorbing anisotropic film according to any one of [1] to [4], which is formed on an alignment film.
- [6] The light absorption anisotropy according to any one of [1] to [5], which contains an azo dye represented by the following general formula (I) as the dichroic dye and has liquid crystallinity A dichroic dye composition for forming a conductive film.
- R 1 to R 4 each independently represents a hydrogen atom or a substituent
- R 5 and R 6 each independently represent a hydrogen atom or an alkyl group which may have a substituent
- L 1 represents —N ⁇ N—, —CH ⁇ N—, —N ⁇ CH—, —C ( ⁇ O) O—, —OC ( ⁇ O) —, or —CH ⁇ CH—
- a 1 represents Represents a phenyl group which may have a substituent, a naphthyl group which may have a substituent, or an aromatic heterocyclic group which may have a substituent
- B 1 represents a substituent.
- R 7 and R 8 each independently represents a hydrogen atom, a methyl group, or an ethyl group
- L 1a represents —N ⁇ N—, —CH ⁇ N—, —N ⁇ CH—, —C ( ⁇ O) O—, —OC ( ⁇ O) —, or —CH ⁇ CH—
- a 1a represents a group represented by the following general formula (IIa) or (IIIa)
- B 1a and B 2a each independently represents a group represented by the following formula (IVa), (Va), or (VIa);
- R 9 has an alkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent.
- n an integer of 0-2.
- the azo dye having a nematic liquid crystal property represented by the general formula (I) is an azo dye represented by the following general formula (Ib) or (Ic): 7].
- R 10 and R 11 each independently represents a hydrogen atom, a methyl group, or an ethyl group;
- L 1b represents —N ⁇ N— or —C ( ⁇ O) O—;
- L 2b represents , —CH ⁇ N—, —N ⁇ CH—, —C ( ⁇ O) O—, or —OC ( ⁇ O) —;
- a 1b is represented by the following formula (IIa) or (IIIa) M1 and n1 each independently represents an integer of 0 to 2;
- R 9 has an alkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent. Represents an oxycarbonyl group which may be substituted or an acyloxy group which may have a substituent.
- R 12 and R 13 represent a hydrogen atom, a methyl group, or an ethyl group, and A 1c represents a group represented by the following formula (IIa) or (IIIa);
- R 9 has an alkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent. Represents an oxycarbonyl group which may be substituted or an acyloxy group which may have a substituent.
- a novel light-absorbing anisotropic film having high dichroism and achromatic color can be provided.
- an achromatic polarizing element having excellent heat resistance and light resistance and excellent polarization performance can be provided.
- FIG. 1 is an X-ray diffraction pattern of the light absorption anisotropic film prepared in Example 1.
- FIG. 2 is an X-ray diffraction pattern of the light absorption anisotropic film prepared in Example 2.
- FIG. 3 is an X-ray diffraction pattern of the light absorption anisotropic film prepared in Example 3.
- FIG. 4 is an X-ray diffraction pattern of the light absorption anisotropic film prepared in Example 4.
- FIG. 5 is an X-ray diffraction pattern of the light absorption anisotropic film prepared in Comparative Example 1.
- the novel light absorption anisotropic film of the present invention is formed from a dichroic dye composition containing at least one of the following specific dichroic dyes and having liquid crystallinity.
- the dichroic dye in the dichroic dye composition of the present invention is not particularly limited as long as it has liquid crystallinity, and examples thereof include azo dyes, cyanine dyes, azo metal complexes, phthalocyanine dyes, Examples thereof include pyrylium dyes, thiopyrylium dyes, azurenium dyes, squarylium dyes, quinone dyes, triphenylmethane dyes, and triallylmethane dyes.
- An azo dye or an azo metal complex is preferable.
- the “dichroic dye” means a dye having different absorbance depending on the direction.
- “dichroism” and “dichroic ratio” are the absorbance of polarized light in the absorption axis direction relative to the absorbance of polarized light in the polarization axis direction when the dichroic dye composition is a light absorption anisotropic film. Calculated as a ratio.
- the dichroic dye composition in the present invention particularly preferably contains at least one azo dye represented by the following general formula (I).
- R 1 to R 4 each independently represents a hydrogen atom or a substituent
- R 5 and R 6 each independently represent a hydrogen atom or an alkyl group which may have a substituent
- L 1 represents —N ⁇ N—, —CH ⁇ N—, —N ⁇ CH—, —C ( ⁇ O) O—, —OC ( ⁇ O) —, or —CH ⁇ CH—
- a 1 represents Represents a phenyl group which may have a substituent, a naphthyl group which may have a substituent, or an aromatic heterocyclic group which may have a substituent
- B 1 represents a substituent.
- n represents an integer of 1 to 5, and when n is 2 or more, a plurality of B 1 are the same as each other It may or may not be.
- This azo dye is a novel dye exhibiting dichroism, excellent color tone and solubility in solvents, and high stability in solution. Therefore, it can be used for various purposes, but when used for a light absorption anisotropic film, a particularly high effect can be obtained. That is, the light absorption anisotropic film of the present invention using this dye exhibits high dichroism, and at the same time, has higher heat resistance, light resistance, and moisture and heat resistance than conventional iodine-based polarizing films.
- the azo dye of the present invention is preferably applied to the formation of a light absorption anisotropic film by applying an organic solvent solution described later and drying.
- a light absorption anisotropic film can be formed on a high heat resistant support such as glass, and a high heat resistant polarizing element can be obtained.
- examples of the substituent represented by R 1 to R 4 include the following groups.
- An alkyl group preferably an alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group and the like), alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, Particularly preferred are alkenyl groups having 2 to 8 carbon atoms, including, for example, vinyl group, aryl group, 2-butenyl group, 3-pentenyl group and the like, and alkynyl groups (preferably having 2 to 20 carbon atoms, more
- An aryl group (preferably an aryl group having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as a phenyl group, a 2,6-diethylphenyl group, 3,5-ditrifluoromethylphenyl group, naphthyl group, biphenyl group and the like), substituted or unsubstituted amino group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, and particularly preferably carbon atoms).
- An amino group having a number of 0 to 6, and examples thereof include an unsubstituted amino group, a methylamino group, a dimethylamino group, a diethylamino group, and an anilino group),
- An alkoxy group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, and a butoxy group), an oxycarbonyl group (Preferably having 2 to 20 carbon atoms, more preferably 2 to 15 carbon atoms, particularly preferably 2 to 10 carbon atoms such as methoxycarbonyl group, ethoxycarbonyl group, phenoxycarbonyl group, etc.), acyloxy group (preferably Has 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms such as an acetoxy group and a benzoyloxy group), an acylamino group (preferably having 2 to 20 carbon atoms, More preferably, it has 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms.
- alkoxycarbonylamino group preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, such as a methoxycarbonylamino group.
- Aryloxycarbonylamino group preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms, particularly preferably having 7 to 12 carbon atoms, and examples thereof include a phenyloxycarbonylamino group).
- a sulfonylamino group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, such as a methanesulfonylamino group and a benzenesulfonylamino group), sulfamoyl Group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, particularly preferably The number of carbon atoms is 0 to 6, for example, sulfamoyl group, methylsulfamoyl group, dimethylsulfamoyl group, phenylsulfamoyl group, etc.), carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably Having 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include an unsubstituted carbamoyl group, a methylcarbamoyl group, a diethylcar
- An alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, such as a methylthio group and an ethylthio group), an arylthio group (preferably a carbon atom) 6 to 20, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as a phenylthio group, and a sulfonyl group (preferably 1 to 20 carbon atoms, more preferably carbon atoms).
- 1 to 10 particularly preferably 1 to 6 carbon atoms such as mesyl group and tosyl group
- sulfinyl group preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, especially Preferably, it has 1 to 6 carbon atoms, and examples thereof include methanesulfinyl group and benzenesulfinyl group, and ureido group (preferably carbon number).
- a phosphoric acid amide group (preferably Has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include a diethylphosphoric acid amide group and a phenylphosphoric acid amide group), a hydroxy group, a mercapto group Group, halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, azo group, heterocyclic group (preferably having 1 carbon atom) To 30 and more preferably 1 to 12, for example, a heterocyclic group having
- silyl group preferably having 3 to 3 carbon atoms 40, more preferably a silyl group having 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms, and examples thereof include a trimethylsilyl group and a triphenylsilyl group.
- substituents may be further substituted with these substituents. Further, when two or more substituents are present, they may be the same or different. If possible, they may be bonded to each other to form a ring.
- the group represented by R 1 to R 4 is preferably a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, particularly preferably a hydrogen atom, an alkyl group or an alkoxy group, most preferably a hydrogen atom or methyl It is a group.
- the alkyl group which may have a substituent represented by R 5 and R 6 is preferably an alkyl having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms. Groups such as a methyl group, an ethyl group, and an n-octyl group.
- the substituent of the alkyl group represented by R 5 and R 6 has the same meaning as the substituent represented by R 1 to R 4 .
- R 5 and R 6 represent an alkyl group, they may be linked to each other to form a ring structure.
- R 5 or R 6 represents an alkyl group, it may be linked to R 2 or R 4 to form a ring structure.
- R 5 and R 6 are particularly preferably a hydrogen atom or an alkyl group, and most preferably a hydrogen atom, a methyl group or an ethyl group.
- a 1 represents a phenyl group which may have a substituent, a naphthyl group which may have a substituent, or an aromatic heterocyclic group which may have a substituent.
- substituents that the phenyl group or the naphthyl group may have include a group that is introduced to improve the solubility and nematic liquid crystal properties of the azo compound, and an electron that is introduced to adjust the color tone as a dye.
- a group having a donating property or an electron-withdrawing property, or a group having a polymerizable group introduced for fixing the orientation is preferable, and specifically, the same as the substituents represented by R 1 to R 4. is there.
- an alkyl group which may have a substituent an alkenyl group which may have a substituent, an alkynyl group which may have a substituent, an aryl group which may have a substituent
- An aryl group which may have a substituent an alkoxy group which may have a substituent, an oxycarbonyl group which may have a substituent, an acyloxy group which may have a substituent, a nitro group, an imino group, An azo group.
- substituents those having a carbon atom have the same preferable range of the number of carbon atoms as the preferable range of the number of carbon atoms for the substituents represented by R 1 to R 4 .
- the phenyl group or the naphthyl group may have 1 to 5 of these substituents, and preferably 1 of them. More preferably, the phenyl group has one substituent at the para position with respect to L 1 .
- aromatic heterocyclic group a group derived from a monocyclic or bicyclic heterocyclic ring is preferable.
- atoms other than carbon constituting the aromatic heterocyclic group include a nitrogen atom, a sulfur atom, and an oxygen atom.
- the aromatic heterocyclic group has a plurality of atoms constituting a ring other than carbon, these may be the same or different.
- aromatic heterocyclic group examples include a pyridyl group, a quinolyl group, a thiophenyl group, a thiazolyl group, a benzothiazolyl group, a thiadiazolyl group, a quinolonyl group, a naphthalimidoyl group, a thienothiazolyl group, and a group derived from the following heterocyclic ring.
- a pyridyl group a quinolyl group, a thiophenyl group, a thiazolyl group, a benzothiazolyl group, a thiadiazolyl group, a quinolonyl group, a naphthalimidoyl group, a thienothiazolyl group, and a group derived from the following heterocyclic ring.
- R 12 to R 16 each independently represent a hydrogen atom, an alkyl group which may have a substituent, or a phenyl group which may have a substituent.
- the substituent is synonymous with the group exemplified as the group which may be substituted on the alkyl group, and its preferred range is also the same.
- a pyridyl group, a quinolyl group, a thiazolyl group, a benzothiazolyl group, a thiadiazolyl group, or a thienotiazolyl group is preferable, and a pyridyl group, a benzothiazolyl group, a thiadiazolyl group, or a thienothiazolyl group is particularly preferable, and a pyridyl group, a benzothiazolyl group Or a thienothiazolyl group is most preferred.
- a 1 is particularly preferably an optionally substituted phenyl group, pyridyl group, benzothiazolyl group, or thienothiazolyl group.
- B 1 represents a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group which may have a substituent.
- n represents an integer of 1 to 5, and when n is 2 or more, the plurality of B 1 may be the same as or different from each other.
- the aromatic hydrocarbon group is preferably a phenyl group or a naphthyl group.
- substituents that the aromatic hydrocarbon group may have include an alkyl group that may have a substituent, an alkoxy group that may have a substituent, a hydroxy group, a nitro group, and a halogen atom.
- the substituent that the aromatic hydrocarbon group may have is preferably an alkyl group that may have a substituent, an alkoxy group that may have a substituent, a hydroxy group, or a halogen atom,
- An alkyl group which may have a substituent, an alkoxy group which may have a substituent, and a halogen atom are particularly preferable, and a methyl group and a halogen atom are most preferable.
- the aromatic heterocyclic group a group derived from a monocyclic or bicyclic heterocyclic ring is preferable.
- atoms other than carbon constituting the aromatic heterocyclic group include a nitrogen atom, a sulfur atom, and an oxygen atom.
- the aromatic heterocyclic group has a plurality of atoms constituting a ring other than carbon, these may be the same or different.
- Specific examples of the aromatic heterocyclic group include a pyridyl group, a quinolyl group, an isoquinolyl group, a benzothiadiazole group, a phthalimide group, and a thienothiazole group. Of these, a thienothiazole group is particularly preferable.
- Examples of the substituent that the aromatic heterocyclic group may have include an alkyl group such as a methyl group and an ethyl group, an alkoxy group such as a methoxy group and an ethoxy group, an unsubstituted or an amino group such as a methylamino group, acetyl Examples thereof include an amino group, an acylamino group, a nitro group, a hydroxy group, a cyano group, and a halogen atom.
- those having a carbon atom have the same preferable range of the number of carbon atoms as the preferable range of the number of carbon atoms for the substituents represented by R 1 to R 4 .
- N represents an integer of 1 to 5, preferably an integer of 1 or 2.
- Preferred examples of the azo dye represented by the general formula (I) include azo dyes represented by any of the following general formulas (Ia) to (Ic).
- R 7 and R 8 each independently represent a hydrogen atom, a methyl group, or an ethyl group
- L 1a represents —N ⁇ N—, —CH ⁇ N—, —N ⁇ CH—, —C ( ⁇ O) O—, —OC ( ⁇ O) —, or —CH ⁇ CH—
- a 1a represents a group represented by the following formula (IIa) or (IIIa)
- B 1a and B 2a Each independently represents a group represented by the following formula (IVa), (Va), or (VIa);
- R 9 has an alkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent.
- m represents an integer of 0-2.
- R 10 and R 11 each independently represents a hydrogen atom, a methyl group, or an ethyl group
- L 1b represents —N ⁇ N— or —C ( ⁇ O) O—
- L 2b represents —CH ⁇ N—, —N ⁇ CH—, —C ( ⁇ O) O—, or —OC ( ⁇ O) —
- a 1b represents a group represented by the above formula (IIa) or (IIIa) M1 and n1 each represents an integer of 0-2.
- R 12 and R 13 represent a hydrogen atom, a methyl group, or an ethyl group
- a 1c represents a group represented by the above formula (IIa) or (IIIa).
- examples of the substituent each group has are the same as the examples of the substituents represented by R 1 to R 4 in the general formula (I). is there.
- groups having carbon atoms such as alkyl groups
- the preferred range of the number of carbon atoms is the same as the preferred range of the number of carbon atoms for the substituents represented by R 1 to R 4 .
- the compound represented by the general formula (I), (Ia), (Ib) or (Ic) may have a polymerizable group as a substituent. It is preferable to have a polymerizable group because the hardening property is improved. Furthermore, the heat resistance is also improved.
- the polymerizable group is not particularly limited, but the polymerization reaction is preferably addition polymerization (including ring-opening polymerization) or condensation polymerization. In other words, the polymerizable group is preferably a polymerizable group capable of addition polymerization reaction or condensation polymerization reaction.
- Et represents an ethyl group
- Pr represents a propyl group.
- the polymerizable group a polymerizable group that undergoes radical polymerization or cationic polymerization is preferable.
- the radical polymerizable group a generally known radical polymerizable group can be used, and a (meth) acrylate group can be mentioned as a preferable one.
- the cationic polymerizable group generally known cationic polymerizable groups can be used. Specifically, alicyclic ether group, cyclic acetal group, cyclic lactone group, cyclic thioether group, spiro orthoester group, vinyloxy group Examples include groups. Of these, alicyclic ether groups and vinyloxy groups are preferred, and epoxy groups, oxetanyl groups, and vinyloxy groups are particularly preferred.
- the polymerizable group is particularly preferably a radical polymerizable group.
- the polymerizable group is preferably located at the molecular end, that is, in the formula (I), preferably present as a substituent for R 5 and / or R 6 and as a substituent for A 1 .
- the compound represented by the general formula (I) (azo dye) is “Dichroic Dyes for Liquid Crystal Display” (A. V. Ivashchenko, CRC, 1994), “Review Synthetic Dye” (Horiguchi Hiroshi, It can be synthesized with reference to the methods described in Sankyo Publishing, 1968) and references cited therein.
- the azo dye represented by the general formula (I) in the present invention can be easily synthesized according to the method described in Journal of Materials Chemistry (1999), 9 (11), 275-2763, and the like.
- the molecular shape of the azo dye represented by the general formula (I) is flat and linear, has a rigid core portion and flexible side chain portions, and Since the azo dye has a polar amino group at the molecular long-axis end, it has a characteristic that it itself easily exhibits liquid crystallinity, particularly nematic liquid crystallinity.
- the dichroic dye composition containing at least one dichroic dye represented by the above (I) has liquid crystallinity.
- the azo dye represented by the general formula (I) has high molecular planarity, it has a strong intermolecular interaction, and has a property that molecules tend to form an associated state.
- the dichroic dye composition containing the azo dye represented by the general formula (I) according to the present invention not only exhibits high absorbance in a wide visible wavelength region by association formation, but also contains this dye. Since the obtained composition specifically has nematic liquid crystallinity, for example, a higher-order molecular alignment state can be realized through a lamination process such as application to the surface of a rubbed polyvinyl alcohol alignment film. Therefore, if the dichroic dye composition containing the azo dye represented by the general formula (I) according to the present invention is used as a light absorption anisotropic film, a polarizing element having high polarization characteristics can be produced. it can.
- the dichroic dye composition of the present invention can increase the dichroic ratio (D) calculated by the method described in the examples described later to 15 or more, and preferably (D) is 18 or more.
- the liquid crystallinity of the azo dye represented by the general formula (I) preferably exhibits a nematic liquid crystal phase at 10 to 300 ° C., more preferably 100 to 250 ° C.
- the dichroic dye composition in the present invention contains one or more azo dyes represented by the general formula (I).
- azo dyes represented by the general formula (I) Although there is no restriction
- the azo dye represented by the general formula (Ia) of the present invention is a magenta azo dye, and the azo dye represented by the general formula (Ib) is a yellow or magenta azo dye represented by the general formula (Ic).
- the azo dye is a cyan azo dye.
- the dichroic dye composition contains the azo dye represented by general formula (Ib) or (Ic).
- the dichroic dye composition contains at least one azo dye represented by the general formula (Ia) and at least one azo dye represented by the general formula (Ib) or (Ic). It is preferable.
- the dichroic dye composition includes at least one azo dye represented by the general formula (Ia), at least one compound represented by the general formula (Ib), and at least one (Ic).
- the dichroic dye composition may further contain a coloring material that is a dye other than the azo dye represented by the general formula (I) as long as the effects of the present invention are not impaired.
- the dye other than the azo dye represented by the general formula (I) is also preferably selected from compounds exhibiting liquid crystallinity. Examples of the dye that can be used in combination include those described in “Dichroic Dyes for Liquid Crystal Display” (A. V. Ivashchenko, CRC, 1994).
- the dichroic dye composition contains at least one azo dye represented by the general formula (I) as a main component.
- the content of the azo dye represented by the general formula (I) is preferably 80% by mass or more, and 90% by mass or more with respect to the total content of all the contained dyes. It is particularly preferred that The upper limit is 100% by mass, that is, all the dyes contained may of course be azo dyes represented by the general formula (I).
- the content of the azo dye represented by one or more general formulas (I) is preferably 20% by mass or more. 30% by mass or more is particularly preferable.
- the upper limit is not particularly limited, but in an embodiment containing other additives such as the following surfactants, in order to obtain those effects, all solids except for the solvent contained in the dichroic dye composition are included.
- the content of one or more azo dyes represented by the general formula (I) in the minute is preferably 95% by mass or less, and more preferably 90% by mass or less.
- the dichroic dye composition used in the present invention may contain a surfactant together with one or more azo dyes.
- the surfactant will be added for the purpose of preventing wind unevenness and the like during application when the composition is prepared as an application liquid and applied.
- a fluorine-type polymer can be used conveniently. There is no restriction
- fluoropolymers that can be used as surfactants include JP-A No. 2004-198511, JP-A No. 4190275, JP-A No. 2004-333852, JP-A No.
- the amount of the surfactant used for preventing wind unevenness is preferably about 0.1 to 10% by mass with respect to the azo dye. It is more preferably about 5 to 10% by mass, and further preferably about 0.5 to 5% by mass.
- Non-liquid crystalline polyfunctional monomer having radical polymerizable group The dichroic dye composition preferably contains a non-liquid crystalline polyfunctional monomer having a radical polymerizable group.
- the “non-liquid crystalline polyfunctional monomer having a radical polymerizable group” refers to a non-liquid crystalline monomer that is a polyfunctional monomer in which a growth active species undergoes a radical polymerization reaction.
- This polyfunctional monomer is preferably a polyfunctional monomer having two or more double bonds in the molecule, particularly preferably an ethylenic (aliphatic) unsaturated double bond, specifically, Multifunctional monomers having functional groups such as alkenes, dienes, acrylates, methacrylates, diesters of unsaturated polycarboxylic acids, amides of ⁇ , ⁇ -unsaturated carboxylic acids, unsaturated nitriles, styrene and derivatives thereof, vinyl esters, vinyl ethers, etc. Can be mentioned.
- the number of double bonds in the molecule is preferably 2-20, more preferably 2-15, and even more preferably 2-6.
- the polyfunctional monomer is preferably an ester of a polyol having two or more hydroxyl groups in the molecule and an unsaturated fatty acid.
- unsaturated fatty acids include acrylic acid, methacrylic acid, maleic acid and itaconic acid, with acrylic acid and methacrylic acid being preferred.
- the polyol having 4 or more hydroxyl groups in the molecule is preferably a tetrahydric or higher alcohol or a trihydric or higher alcohol oligomer.
- the oligomer has a molecular structure in which polyhydric alcohols are linked by an ether bond, an ester bond or a urethane bond. Oligomers having a molecular structure in which polyhydric alcohols are linked by ether bonds are preferred.
- the polyfunctional monomer is particularly preferably soluble in an organic solvent.
- An example of such a monomer is a compound having a boiling point of 100 ° C. or higher at normal pressure.
- examples of the bifunctional (meth) acrylate include ethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, Polypropylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, bisphenoxyethanol full orange acrylate, etc. can be mentioned.
- Examples of commercially available products include Aronix M-210, M-240, and M-6200 Synthetic Chemical Industry Co., Ltd.), KAYARAD HDDA, HX-220, R-604 (Nippon Kayaku Co., Ltd.), Biscote 260, 312 and 335HP (Osaka Organic Chemical Co., Ltd.) ( All of them are trade names).
- Examples of the trifunctional or higher functional (meth) acrylate include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tri ((meth) acryloyloxyethyl) phosphate, pentaerythritol tetra (meth) acrylate, Examples thereof include dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate, and examples of commercially available products thereof include Aronix M-309, M-400, M-405, M-450, and the like.
- M-7100, M-8030, M-8060 all trade names, manufactured by Toa Gosei Chemical Industry Co., Ltd.
- KAYARAD TMPTA, DPHA, DPCA-20, DPCA-30, DPCA-60, DPCA-120 both Product name, manufactured by Nippon Kayaku Co., Ltd.
- BISCOAT 295, the 300, the 360, the same GPT, the same 3PA, the 400 (trade name, manufactured by Osaka Organic Chemical Industry Co., Ltd.), and the like.
- bifunctional or trifunctional or higher (meth) acrylates include, for example, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolethane triacrylate, trimethylolpropane diacrylate.
- Monomers composed of an ester of polyol and acrylic acid are commercially available from Mitsubishi Rayon Co., Ltd. (trade name: Diabeam UK-4154) and Nippon Kayaku Co., Ltd. (trade name: KAYARAD / DPHA, SR355).
- bifunctional or trifunctional or higher functional (meth) acrylates may be used alone or in combination, and may be used in combination with monofunctional (meth) acrylate.
- Examples of monofunctional (meth) acrylates include 2-hydroxyethyl (meth) acrylate, carbitol (meth) acrylate, isobornyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, and 2- (meth) acryloyloxyethyl.
- 2-Hydroxypropyl phthalate polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, phenoxyethyl (meth) acrylate, ethylene glycol (meth) acrylate, and the like.
- the polymerization reaction includes a thermal polymerization reaction using a thermal polymerization initiator and a photopolymerization reaction using a photopolymerization initiator.
- the total content of the one or more azo dyes and the non-liquid crystalline polymerizable polyfunctional monomer in the total solid content excluding the solvent is preferably 50% by mass or more, and 70% by mass. % Or more is particularly preferable.
- Polymerization initiator In a composition containing a non-liquid crystalline polyfunctional monomer having a radical polymerizable group, it is preferable to contain a polymerization initiator in order to cause a curing reaction of the monomer.
- a polymerization initiator known ones can be suitably used according to photopolymerization and thermal polymerization.
- ⁇ -carbonyl compounds US Pat. Nos. 2,367,661 and 2,367,670
- Acyloin ether described in US Pat. No. 2,448,828)
- ⁇ -hydrocarbon-substituted aromatic acyloin compound described in US Pat. No.
- the dichroic dye composition is cured by photopolymerization
- it is contained in the photo-alignment film layer so as not to disturb the orientation of the photo-alignment film layer when the photo-alignment film layer is positioned below the dichroic dye composition.
- a photopolymerization initiator having a light absorption wavelength band different from the light absorption band of the photoactive compound.
- a compound that absorbs light having a wavelength longer than the absorption band of a normal photopolymerization initiator and induces a polymerization reaction by causing energy transfer to the polymerization initiator may be mixed.
- the dichroic dye composition can be polymerized without disturbing the alignment state of the photoalignment film composition fixed by the photoalignment operation.
- the dichroic dye composition in order to initiate the polymerization of the dichroic dye composition, when light irradiation is performed from the same direction as the photo-alignment operation, or polarized light irradiation having a polarization plane orthogonal to the absorption transition moment of the photoactive compound is performed. Since there is no fear of disturbing the alignment state of the photo-alignment film layer, light having an arbitrary wavelength can be used, and the range of selection of the polymerization initiator is widened.
- photoalignment and photopolymerization can be performed simultaneously.
- photo-alignment is performed in an atmosphere that inhibits polymerization, for example, in the air, and only photo-alignment is performed. It can also be made.
- polymerization by heat it is preferably carried out at 80 to 200 ° C, more preferably 80 to 160 ° C. In this case, it is preferable to add a thermal polymerization initiator.
- the photoinitiator used by this invention can use a well-known and usual thing.
- photopolymerization initiators that can be used with ultraviolet light of 320 nm or less, 1-hydroxycyclohexyl phenyl ketone (product name “Irgacure 184”, manufactured by Ciba Specialty Chemicals), 1- [4- (2-hydroxyethoxy) -phenyl ] 2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one (trade name “Darocur 1173” manufactured by Merck & Co., Inc.) .
- Examples of the photopolymerization initiator having a light absorption wavelength band different from the light absorption band of the azobenzene skeleton include those obtained by combining a near infrared absorbing dye and organic boron described in Japanese Patent No. 3016606. .
- photopolymerization initiators examples include 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one (trade name “Darocur 1116” manufactured by Merck & Co., Inc.), 2-methyl-1 -[(Methylthio) phenyl] -2-morpholinopropane-1 (Ciba Specialty Chemicals, trade name “Irgacure 907”), benzylmethylketal (Ciba Specialty Chemicals “Irgacure 651”) ), 2,4-diethylthioxanthone (Nippon Kayaku Co., Ltd., trade name “Kayacure DETX”) and ethyl p-dimethylaminobenzoate (Nippon Kayaku Co., Ltd., trade name “Kayacure EPA”), isopropylthioxanthone (Trade name “Cancure-ITX” manufactured by Word Prekinsop) and p
- thermal polymerization initiator used in the thermal polymerization known ones can be used.
- methyl acetoacetate peroxide cumene hydroperoxide, benzoyl peroxide, bis (4-t-butyl) (Cyclohexyl) peroxydicarbonate, t-butylperoxybenzoate, methyl ethyl ketone peroxide, 1,1-bis (t-hexylperoxy) 3,3,5-trimethylcyclohexane, p-pentahydroperoxide
- Organic peroxides such as t-butyl hydroperoxide, dicumyl peroxide, isobutyl peroxide, di (3-methyl-3-methoxybutyl) peroxydicarbonate, 1,1-bis (t-butylperoxy) cyclohexane Oxide, 2,2′-azobisisobutyronitrile, Azonitrile compounds such as 2,2′-azobis (2,4-dimethylval
- the amount of the photopolymerization initiator used is preferably 0.01 to 20% by mass, more preferably 1 to 10% by mass, based on the total solid content excluding the solvent.
- Examples of the photopolymerization initiator, the amount of the photopolymerization initiator used, and the value of the light irradiation energy for polymerization are also described in paragraphs [0050] to [0051] of JP-A No. 2001-91741. Applicable to the invention.
- the one or more nematic liquid crystalline azo dyes, a surfactant, a non-liquid crystalline polyfunctional monomer having a radical polymerizable group, which is optionally added In addition to the polymerization initiator, any additive can be blended and used in combination.
- additives include non-liquid crystalline binder polymers, anti-repellent agents, additives for controlling the tilt angle of the alignment film (tilt angle of the liquid crystalline azo dye at the polarizing layer / alignment film interface), air interface Additive for controlling the tilt angle (tilt angle of the liquid crystalline azo dye at the polarizing layer / air interface), a saccharide, an agent having at least one of antifungal, antibacterial and antibacterial functions.
- each additive will be described.
- Non-liquid crystalline binder polymer may be added to the dichroic dye composition used in the present invention.
- non-liquid crystalline polymers include acrylic resins such as polyacrylonitrile, polyacrylic acid esters, and polyacrylamide, polyvinyl acetal resins such as polystyrene resin, polyvinyl acetoacetal, and polyvinyl butyral, ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxy cellulose, hydroxy Modified cellulose resins such as propyl cellulose, ethyl hydroxyethyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cellulose nitrate, etc., cellulose resins such as ethyl hydroxyethyl cellulose and ethyl cellulose, polyurethane resins, polyamide resins, Polyester resin, polycarbonate resin, phenoxy resin
- non-liquid crystalline binder polymer an acrylic polymer (a resin having an acrylic copolymer or a styrene copolymer as a main chain) is particularly preferable, and it is particularly preferable that the non-liquid crystalline binder polymer is soluble in an organic solvent.
- a known radical polymerization method can be applied.
- Polymerization conditions such as temperature, pressure, type and amount of radical initiator, type of solvent, etc. in the production by the radical polymerization method can be easily set by those skilled in the art, and the conditions should be determined experimentally. You can also.
- unsaturated carboxylic acid eg, (meth) acrylic acid, crotonic acid, itaconic acid, maleic acid and fumaric acid
- aromatic vinyl compound eg, styrene, ⁇ -methylstyrene, vinyltoluene, 2-vinylpyridine, 4-vinylpyridine, N-vinylimidazole, etc.
- acrylic acid alkyl esters eg, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl) (Meth) acrylate, i-butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, dodecyl (meth) acrylate, etc.
- acrylic acid alkyl aryl ester eg, benzyl (meth) acrylate, etc.
- unsaturated carboxylic acids aromatic vinyl compounds, (meth) acrylic acid alkyl esters, (meth) acrylic acid alkyl aryl esters and carboxylic acid vinyl esters are preferred.
- (meth) acrylic acid is a general term that combines acrylic acid and methacrylic acid
- (meth) acrylate is also a general term for acrylate and methacrylate.
- an acrylic polymer having a (meth) acryloyl group in the side chain or a macromonomer for example, a polystyrene macromonomer, a polymethyl methacrylate macromonomer, a polyethylene glycol mono (meth) acrylate, a polypropylene glycol mono (meth) acrylate, a polyethylene as a copolymerization component
- An acrylic graft polymer containing glycol polypropylene glycol mono (meth) acrylate and the like is also preferable. These can be used alone or in combination of two or more.
- a polymer compound can be added as a material for preventing repelling during coating.
- the polymer compound used for this purpose is not particularly limited as long as it is compatible with the liquid crystalline azo dye and does not significantly inhibit the tilt angle change or orientation of the dye.
- Examples of polymers that can be used as repellency inhibitors are described in JP-A-8-95030, and specific examples of particularly preferred polymers include cellulose esters. Examples of cellulose esters include cellulose acetate, cellulose acetate propionate, hydroxypropyl cellulose, and cellulose acetate butyrate.
- the amount of the polymer used for the purpose of preventing repellency is generally preferably in the range of 0.1 to 10% by mass with respect to the liquid crystalline azo dye. It is more preferably in the range of ⁇ 8% by mass, and still more preferably in the range of 0.1 to 5% by mass.
- Alignment film tilt angle control agent An additive for controlling the tilt angle of the liquid crystalline azo dye molecules on the alignment film side may be added to the dichroic dye composition.
- the additive having such an action include compounds having both a polar group and a nonpolar group in the molecule.
- the compounds having both polar and nonpolar groups in the molecule include P O —OH, P O —COOH, P O —O—P O , P O —NH 2 , P O —NH—P O , P O -SH, P O -S-P O, P O -CO-P O, P O -COO-P O, P O -CONH-P O, P O -CONHCO-P O, P O -SO 3 H , P O —SO 3 —P O , P O —SO 2 NH—P O , P O —SO 2 NHSO 2 —P O , P O —C ⁇ N—P O , HO—P (—OP O ) 2 , (HO-) 2 PO-OP O , P (-OP O ) 3 , HO-PO (-OP O ) 2 , (HO-) 2 PO-OP O , PO (-OP O ) 3 , P O- Preferred examples include NO 2 and P O —
- organic salt in addition to the organic salt of the above compound (for example, ammonium salt, carboxylate, sulfonate, etc.), pyridinium salt and the like can be preferably employed.
- organic salt in addition to the organic salt of the above compound (for example, ammonium salt, carboxylate, sulfonate, etc.), pyridinium salt and the like can be preferably employed.
- P O —OH, P O —COOH, P O —O—P O , P O —NH 2 , P O —SO 3 H, HO -PO (-OP O ) 2 , (HO-) 2 PO-OP O , PO (-OP O ) 3 or an organic salt thereof is preferred.
- each P O represents a nonpolar group, and when there are a plurality of P O , they may be the same or different.
- an alkyl group preferably a linear, branched or cyclic substituted or unsubstituted alkyl group having 1 to 30 carbon atoms
- an alkenyl group preferably a linear or branched chain having 1 to 30 carbon atoms, Cyclic substituted or unsubstituted alkenyl groups
- alkynyl groups preferably linear, branched, cyclic substituted or unsubstituted alkenyl groups having 1 to 30 carbon atoms
- aryl groups preferably having 6 to 30 carbon atoms.
- Examples thereof include substituted or unsubstituted aryl groups) and silyl groups (preferably substituted or unsubstituted silyl groups having 3 to 30 carbon atoms). These nonpolar groups may further have a substituent.
- substituent include a halogen atom, an alkyl group (including a cycloalkyl group and a bicycloalkyl group), an alkenyl group (a cycloalkenyl group and a bicycloalkenyl group).
- the addition amount of the alignment film tilt angle controlling agent is preferably about 0.0001% by mass to 30% by mass, and preferably 0.001% by mass to 20% by mass with respect to the mass of the liquid crystalline azo dye. More preferably, it is about mass%, more preferably about 0.005 mass% to 10 mass%.
- the alignment film tilt control agent described in JP-A-2006-58801 can be used.
- Air interface tilt angle control agent (horizontal alignment agent):
- the dichroic dye composition used in the present invention preferably contains a horizontal alignment agent as an air interface tilt angle control agent. Since a photo-alignment film layer is used in the present invention, a good homogeneous alignment structure with a particularly small pretilt angle is realized at the interface with the photo-alignment film layer, but since the direction of the pretilt angle is not controlled, the air interface When a tilt angle is generated in, the direction is not constant and a reverse tilt domain may occur. By adding the air interface tilt angle control agent, the orientation of the liquid crystalline azo dye molecules at the air interface can be made horizontal, and the occurrence of reverse tilt domains can be suppressed.
- the horizontal alignment agent used in the present invention is preferably (1) a fluoroaliphatic group-containing compound represented by the following general formula (III); or (2) selected from the group consisting of polymerized units of fluoroaliphatic group-containing monomers represented by general formula (IV) or general formula (V) and polymerized units of amide group-containing monomers represented by general formula (VI)
- R 22 , R 33 and R 44 each independently represents an alkoxy group having a CF 3 group or a CF 2 H group at the terminal, and X 11 , X 22 and X 33 each independently represent —NH—, -O- or -S-, and m22, m33 and m44 each independently represents an integer of 1 to 3.
- the substituent represented by each of R 22 , R 33 and R 44 is an alkoxy group having a CF 3 group or a CF 2 H group at the terminal, and may be linear or branched. Preferably, it has 4 to 20 carbon atoms, more preferably 4 to 16 carbon atoms, and particularly preferably 6 to 16 carbon atoms.
- the alkoxy group having a CF 3 group or a CF 2 H group at the terminal is an alkoxy group in which part or all of the hydrogen atoms contained in the alkoxy group are substituted with fluorine atoms.
- 50% or more of the hydrogen atoms in the alkoxy group are preferably substituted with fluorine atoms, more preferably 60% or more are substituted, and particularly preferably 70% or more are substituted.
- alkoxy group having a CF 3 group or CF 2 H group at the terminal represented by R 22, R 33 and R 44.
- X 11 , X 22 and X 33 each preferably represent —NH— or —O—, and most preferably represents —NH—.
- m22, m33 and m44 are each preferably 2.
- R 51 represents a hydrogen atom, a halogen atom or a methyl group
- L 51 represents a divalent linking group
- m51 represents an integer of 1 to 18.
- R 52 represents a hydrogen atom, a halogen atom, or a methyl group
- L 52 represents a divalent linking group
- n51 represents an integer of 1 to 18.
- R 53 represents a hydrogen atom, a halogen atom or a methyl group
- R 60 and R 61 each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aromatic group having 6 to 20 carbon atoms or a carbon number. 1 to 20 heterocyclic groups are represented. R 60 and R 61 may be connected to each other to form a heterocyclic ring.
- R 51 represents a hydrogen atom, a halogen atom or a methyl group, and more preferably a hydrogen atom or a methyl group.
- L 51 represents a divalent linking group
- m51 represents an integer of 1 to 18, more preferably 2 to 12, still more preferably 4 to 8, and even more preferably 4 or 6.
- R 52 represents a hydrogen atom, a halogen atom or a methyl group, and more preferably a hydrogen atom or a methyl group.
- L 52 represents a divalent linking group
- n51 represents an integer of 1 to 18, more preferably 2 to 12, still more preferably 4 to 8, and most preferably 4 or 6.
- L 51 and L 52 are not limited as long as they are each independently a divalent substituent, but a structure represented by the following general formula (VII) is more preferable.
- (a) shows the position bonded to the double bond side
- (b) shows the position bonded to the fluoroaliphatic group side.
- Formula (VII) (A) -X 10 -R 20 - (b)
- X 10 is a single bond, or * -COO-**, * -COS-**, * -OCO-**, * -CON (R 21 )-**, * -O-.
- R 20 represents an optionally substituted polymethylene group (eg, methylene group, ethylene group, trimethylene group), an optionally substituted phenylene group (eg, o-phenylene group, m-phenylene group).
- R 21 represents a hydrogen atom or an alkyl group which may have a substituent having 1 to 8 carbon atoms, or an aryl group which may have a substituent having 6 to 20 carbon atoms.
- a 1-6 alkyl group is more preferable, and a hydrogen atom or an alkyl group having 1 to 4 carbon atoms is still more preferable.
- the fluoroaliphatic group-containing monomer represented by the general formula (IV) is more preferably a monomer represented by the following general formula (VIII).
- X 1 represents a divalent group represented by —O—, —S— or —N (R 222 ) —, and p represents an integer of 1 to 8.
- X 1 is more preferably —O— or —N (R 222 ) —, and most preferably —O—.
- p is more preferably from 1 to 6, and still more preferably from 1 to 3.
- R 51 and m 51 have the same meanings as described in the general formula (IV), and preferred ranges are also the same.
- R 222 represents a hydrogen atom, an alkyl group which may have a substituent having 1 to 8 carbon atoms, or an aryl group which may have a substituent having 6 to 20 carbon atoms.
- X 2 represents a substituent represented by —O—, —S— or —N (R 222 ) —, and q represents an integer of 1 to 8.
- X 2 is more preferably —O— or —N (R 222 ) —, and most preferably —O—.
- q is more preferably 1 to 6, and still more preferably 1 to 3.
- R 52 and n 51 have the same meanings as described in the general formula (V), and the preferred ranges are also the same.
- R 222 has the same meaning as that described in formula (VIII).
- R 53 represents a hydrogen atom, a halogen atom or a methyl group, more preferably a hydrogen atom or a methyl group.
- R 60 and R 61 each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aromatic group having 6 to 20 carbon atoms or a heterocyclic group having 1 to 20 carbon atoms, and these substituents are further substituted It may have a group.
- R 60 and R 61 may be linked to each other to form a heterocyclic ring.
- the formed heterocyclic ring include a pyrrolidine ring, a piperidine ring, and a morpholine ring.
- the fluoroaliphatic group-containing copolymer used as the horizontal alignment agent includes both a fluoroaliphatic group-containing monomer and an amide group-containing monomer as polymerized units, and each monomer may include two or more kinds of polymerized units.
- the copolymer may include one or more other copolymerizable monomers as polymerized units.
- Other types of such copolymerizable monomers include Polymer Handbook 2nd ed. , J .; Brandrup, Wiley Interscience (1975) Chapter 2, Pages 1-483 can be used. Examples thereof include compounds having one addition polymerizable unsaturated bond selected from acrylic acid esters, methacrylic acid esters, methacrylamides, allyl compounds, vinyl ethers, vinyl esters and the like.
- a preferred mass average molecular weight of the fluoroaliphatic group-containing copolymer used as the horizontal alignment agent is 2000 to 100,000, more preferably 3000 to 80,000, and still more preferably 4,000 to 60,000. 000.
- the mass average molecular weight and the molecular weight are converted to polystyrene by GTH analyzer using a column of TSKgel GMHxL, TSKgel G4000HxL, TSKgel G2000HxL (both are trade names manufactured by Tosoh Corporation) and detected by a solvent THF and a differential refractometer. Is the molecular weight.
- the fluoroaliphatic group-containing copolymer that can be used in the present invention as the horizontal alignment agent will be shown, but the present invention is not limited to the following specific examples.
- the number in a formula shows the mass ratio of each monomer component. Mw represents a mass average molecular weight.
- horizontal alignment agents described in JP-A-2005-99248, JP-A-2005-134484, JP-A-2006-126768, and JP-A-2006-267183 may be selected.
- the addition amount of the horizontal alignment agent in the dichroic dye composition is preferably 0.1% by mass to 10% by mass, and 0.5% by mass with respect to the addition amount of the nematic liquid crystalline azo dye. % To 10% by mass is more preferable, and 0.5% to 5% by mass is particularly preferable.
- Saccharides may be added to the dichroic dye composition used in the present invention. By adding saccharides, the association degree of the dye aggregate can be improved, and as a result, the molecular orientation of the dye can be increased.
- saccharides that can be used include monosaccharides, disaccharides, polysaccharides, and sugar derivatives such as sugar alcohols.
- saccharides in order to achieve the effects of the present invention, those having a hydroxyl group of usually 2 or more, preferably 3 or more, preferably 18 or less, and more preferably 12 or less are preferable from the viewpoint of molecular association.
- the molecular weight of the saccharide used is preferably 1,000 or less, more preferably 700 or less. If the molecular weight of the saccharide is too large, it is not preferred because it may cause phase separation from the dye and impair the orientation of the dye film.
- the carbon number of the saccharide used is usually 36 or less, preferably 24 or less. If the saccharide has too many carbon atoms, the molecular weight of the saccharide increases, which causes phase separation from the azo dye, which may impair the orientation of the dye film.
- monosaccharides include xylose, ribose, glucose, fructose, mannose, sorbose, and galactose.
- oligosaccharide examples include trehalose, kojibiose, nigerose, maltose, maltotriose, isomaltotriose, maltotetraose, isomaltose, sophorose, laminaribiose, cellobiose, gentiobiose, lactose, sucrose, melibiose, lutinose, primiverose, Examples include turanose, panose, isopanose, cellotriose, manninotriose, soratriose, melezitose, planteose, gentianose, umbelliferose, raffinose, stachyose.
- sugar alcohol examples include compounds obtained by reducing the above monosaccharides and oligosaccharides such as threitol, xylitol, ribitol, arabitol, sorbitol, and mannitol.
- saccharide xylose, mannose, maltose, maltotriose and arabitol are particularly preferable.
- saccharides and sugar alcohols each have optical isomers, but each of them may be used alone or both may be included in the composition used in the present invention. Moreover, saccharides may be used individually by 1 type in the composition of this invention, and 2 or more types may be used in combination.
- the saccharide content relative to the one or more liquid crystalline azo dyes is preferably in the range of 0.1 to 1 in terms of mass ratio. More preferably, it is 0.2 or more, particularly preferably 0.3 or more, further preferably 0.7 or less, and particularly preferably 0.6 or less.
- the association degree of the dye aggregate can be increased without decreasing the orientation degree of the aggregate.
- Antifungal, antibacterial and fungicides You may add the chemical
- a drug having at least one of antifungal, antibacterial, and sterilization functions refers to an antifungal ability that suppresses the generation / growth / growth of mold, a sterilizing ability that kills microorganisms, and a microorganism It means a drug having at least one function of antibacterial ability that suppresses the generation, growth and proliferation of sucrose.
- Known antifungal agents, bactericides, and antibacterial agents can be used.
- the optical property of the polarizer formed from the composition is not deteriorated.
- the drug having at least one of antifungal, antibacterial and bactericidal functions include conventional phenols such as 2,4,4′-trichloro-2′-hydroxydiphenyl, chlorine dioxide and the like. And quaternary ammonium salt systems such as benzalkonium chloride.
- Proxel BDN Proxel BD20
- Proxel GXL Proxel LV
- Proxel XL Proxel XL2
- Proxel Ultra10 above, Avecia, trade name
- Polyhexametylene biguanide hydrochloride as an active ingredient
- Proxel IB Avecia, trade name
- Dithio-2,2'-bis (benzmethylamide) as an active ingredient
- Densil P Avecia, trade name
- Densil P Avecia, trade name
- medical agent which has at least any one function of antifungal, antibacterial, and disinfection which can be used by this invention can also be used individually or in combination of 2 or more types.
- the content of the agent having at least one of antifungal, antibacterial and bactericidal functions in the composition is not particularly limited, but is usually 0.01% by mass or more, preferably 0.001% by mass or more. On the other hand, it is usually 0.5% by mass or less, preferably 0.3% by mass or less.
- the content of the drug having at least one of antifungal, antibacterial and sterilizing functions is within the above range, sufficient antifungal and antibacterial can be achieved without causing the precipitation of the drug or phase separation during film formation. Or the bactericidal effect is acquired.
- Electron-Deficient lamellar compounds and Electron-Rich compounds Since the polarizer obtained by the method of the present invention has a high degree of polarization, the composition contains an electron-deficient discotic compound and an electron-rich compound. Is preferred.
- the electron-deficient discotic compound and the electron-rich compound for example, those described in JP-A-2006-323377 can be used.
- the ratio of the electron-deficient discotic compound in the composition is usually 0.1 parts by mass or more, preferably 0.2 parts by mass or more, when the total composition is 100 parts by mass. Moreover, it is 50 mass parts or less normally, Preferably it is the range of 40 mass parts or less. When the ratio of the compound is within this range, the effect of addition can be obtained without excessively increasing the viscosity of the composition as a solution. Moreover, the ratio of the electron-rich compound in the composition is usually 50 parts by mass or less, preferably 40 parts by mass or less when the entire composition is 100 parts by mass. When the ratio of the compound is within this range, the effect of addition can be obtained without excessively increasing the viscosity of the composition as a solution.
- the dichroic dye composition is preferably prepared as a coating solution.
- the solvent used for preparing the coating solution is preferably an organic solvent.
- organic solvents include amides (eg, N, N-dimethylformamide), sulfoxides (eg, dimethyl sulfoxide), heterocyclic compounds (eg, pyridine), hydrocarbons (eg, benzene, toluene, hexane) , Alkyl halides (eg, chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane). Hydrocarbons, alkyl halides and ketones are preferred. Two or more organic solvents may be used in combination.
- the method for preparing the coating solution for the dichroic dye composition is not particularly limited. It is prepared by dissolving the one or more nematic liquid crystalline azo dyes and one or more of the above-mentioned additives (for example, a surfactant, a horizontal alignment agent, etc.) that are optionally added in a solvent.
- the coating liquid may not be completely dissolved but may be dispersed.
- the composition is preferably prepared as a coating solution having a total solid concentration of about 0.1 to 20% by mass, more preferably about 0.1 to 10% by mass, More preferably, it is about 5% by mass.
- the coating liquid is prepared in this concentration range, the polarizing layer can be stably formed by a wet film forming method.
- a coating solution comprising the above-described dichroic dye composition is applied to the alignment film surface to form a light-absorbing anisotropic film in a wet state, and then the anisotropic film is subjected to a drying treatment.
- the organic solvent is evaporated, and the final novel light absorption anisotropic film of the present invention can be formed.
- a light absorption anisotropic film having a high dichroic ratio characterized by a specific sharp diffraction peak can be formed.
- the polarization element is formed by (1) forming a substrate directly or on the substrate. A step of rubbing or irradiating the aligned alignment film; (2) a step of applying a dichroic dye composition on the substrate or the alignment film; and (3) aligning the dichroic dye composition. And a polarizing element.
- Alignment treatment step step of rubbing or irradiating the substrate directly or the alignment film formed on the substrate
- a substrate to be described later is rubbed or irradiated with anisotropic light directly or on an alignment film formed on the substrate.
- Rubbing is an operation of performing an alignment treatment to rub the surface of the substrate or the like with a buff such as cotton cloth or absorbent cotton to form fine grooves parallel to the direction, as will be described in detail later.
- This is an operation of finally adsorbing the dye in an oriented state on the surface by applying a dichroic dye.
- Anisotropic light refers to polarized light such as linearly polarized light and elliptically polarized light, and non-polarized light irradiated from an oblique direction with respect to the coating surface, and this is irradiated to an alignment film containing a photoactive compound described in detail later.
- liquid crystal alignment ability is generated in a certain direction, and by applying a dichroic dye here, the dye can be finally adsorbed on the surface in an aligned state.
- the substrate used in the present invention may be transparent or a support made opaque by coloring or the like, and can be selected according to the use of the polarizer.
- alkali-free glass soda glass, Pyrex (registered trademark) glass, quartz glass used for liquid crystal display elements, OLED elements, etc .; photoelectric conversion element substrate used for solid-state imaging elements, etc .; silicon substrate; plastic substrate; And a substrate on which a functional layer such as a transparent conductive film, a color filter film, an electrode and a TFT is formed.
- a black matrix for isolating each pixel may be formed, or a transparent resin layer may be provided for promoting adhesion.
- these substrates may be subjected to surface treatment.
- the surface treatment include ozone treatment and plasma treatment.
- an organic thin film, an inorganic oxide thin film, a metal thin film, or the like may be provided on the substrate surface by a method such as vapor deposition.
- the plastic substrate has a gas barrier layer and / or a solvent resistant layer on the surface thereof.
- the substrate used in the present invention is preferably a transparent support (transparent support), and preferably has a light transmittance of 80% or more. It is preferable to use glass or an optically isotropic polymer film.
- JP-A-2002-22294 can be applied. Further, even a conventionally known polymer such as polycarbonate or polysulfone that easily develops birefringence is used by reducing the expression by modifying the molecule described in International Publication WO00 / 26705. You can also.
- the polymer film it is preferable to use cellulose acetate having an acetylation degree of 55.0 to 62.5%.
- the acetylation degree is preferably 57.0 to 62.0%.
- the description of paragraph number [0021] of JP-A No. 2002-196146 can be applied to the degree of acetylation, its range, and the chemical structure of cellulose acetate.
- the production of a cellulose acylate film using a non-chlorinated solvent is described in detail in JIII Journal of Technical Disclosure No. 2001-1745, and the cellulose acylate film described therein is also preferably used in the present invention. Can do.
- JP-A No. 2002-139621 can be applied to the retardation value in the thickness direction of the cellulose ester film used as the transparent support and the range of the birefringence.
- an aromatic compound having at least two aromatic rings can also be used as a retardation increasing agent.
- the description in paragraph numbers [0021] to [0023] of JP-A No. 2002-139621 can be applied.
- Such retardation increasing agents are described in International Publication WO01 / 88574A1, International Publication WO00 / 2619A1, JP2000-11914A, 2000-275434, 2002-363343, and the like. Has been.
- the cellulose acylate film is preferably produced from the prepared cellulose acylate solution (dope) by a solvent cast method. It is preferable to add the above-mentioned retardation increasing agent to the dope.
- a film can be formed by casting two or more layers of the dope. The description of paragraph numbers [0038] to [0040] of JP-A No. 2002-139621 can be applied to the formation of the film.
- the retardation of the cellulose acylate film can be further adjusted by stretching.
- the draw ratio is preferably in the range of 3 to 100%.
- tenter stretching is preferably used, and in order to control the slow axis with high accuracy, it is preferable to make the difference between the left and right tenter clip speeds, the separation timing, etc. as small as possible. .
- a plasticizer can be added to the cellulose ester film in order to improve mechanical properties or improve the drying speed.
- the plasticizer the embodiment of paragraph number [0043] and preferred range of JP-A-2002-139621 can be applied to the present invention.
- Degradation inhibitors eg, antioxidants, peroxide decomposers, radical inhibitors, metal deactivators, acid scavengers, amines
- UV inhibitors may be added to the cellulose ester film.
- the description in paragraph [0044] of JP-A-2002-139621 can be applied.
- the deterioration preventing agent butylated hydroxytoluene (BHT) can be mentioned.
- BHT butylated hydroxytoluene
- the ultraviolet ray preventing agent is described in JP-A-7-11056.
- the thickness of the cellulose acylate film varies depending on the purpose of use, but is usually in the range of 5 to 500 ⁇ m, more preferably in the range of 20 to 250 ⁇ m, and most preferably in the range of 30 to 180 ⁇ m.
- the range of 30 to 110 ⁇ m is particularly preferable.
- the alignment film formed on the support may be any layer as long as it can impart a desired alignment to the dichroic dye of the light absorption anisotropic film provided on the alignment film.
- LB film Langmuir-Blodgett method
- Methyl stearylate Methyl stearylate
- an alignment film formed by a rubbing treatment of a polymer and an alignment film formed by anisotropic light irradiation are particularly preferable.
- the thickness of the alignment film is preferably 0.01 to 10 ⁇ m, and more preferably 0.05 to 1 ⁇ m.
- the rubbing treatment can be generally carried out by rubbing the surface of the polymer layer several times in a certain direction with paper or cloth.
- the method described in “Liquid Crystal Handbook” (published by Maruzen) Is preferably performed.
- polyvinyl alcohol and its derivatives are preferably used. Particularly preferred is a modified polyvinyl alcohol having a hydrophobic group bonded thereto.
- alignment film reference can be made to the description on page 43, line 24 to page 49, line 8 of WO01 / 88574A1.
- N is the number of rubbing
- l is the contact length of the rubbing roller
- r is the radius of the roller
- n is the number of rotations (rpm) of the roller
- v is the stage moving speed (second speed).
- the rubbing frequency should be increased, the contact length of the rubbing roller should be increased, the radius of the roller should be increased, the rotation speed of the roller should be increased, and the stage moving speed should be decreased, while the rubbing density should be decreased. To do this, you can reverse this.
- the pretilt angle decreases as the rubbing density increases and the pretilt angle increases as the rubbing density decreases.
- the composition for photo-alignment films for forming the photo-alignment film used in the present invention is a composition that produces liquid crystal alignment ability by light irradiation, and contains a photoactive compound.
- various components used for the preparation of the composition for photo-alignment films will be described.
- Photoactive compounds means a compound having a photoactive group that undergoes a photoreaction such as photocrosslinking, photoisomerization, or photolysis anisotropically by irradiation with anisotropic light. Say. Specific examples of the photoactive compound are described in many documents.
- the composition for forming a photo-alignment film preferably contains the photoactive compound as a main component, and more specifically, the proportion of the composition for forming a photo-alignment film in the total solid content excluding the solvent is azo From the viewpoint of maintaining the orientation to the dye, it is preferably 50% by mass or more, and particularly preferably 70% by mass or more. The upper limit is 100% by mass, that is, all the solid content excluding the solvent of the composition for forming a photoalignment film may of course be the photoactive compound.
- the composition for forming a photo-alignment film may contain one or more additives other than the photoactive compound.
- the additive is added for the purpose of uniformly coating the composition and obtaining a photo-alignment film having a uniform film thickness.
- additives include leveling agents, thixotropic agents, surfactants, ultraviolet absorbers, infrared absorbers, antioxidants, surface treatment agents, and the like, and the alignment ability of nematic liquid crystalline azo dyes used in combination. It can be added to the extent that it does not significantly decrease.
- the composition for forming a photo-alignment film is preferably prepared as a coating solution.
- a solvent used for preparation of this coating liquid Usually, the solvent in which the said photoactive compound melt
- alcohol solvents such as methanol and ethanol
- diol solvents such as ethylene glycol, propylene glycol and 1,3-butanediol, tetrahydrofuran, 2-methoxyethanol, 2-butoxyethanol, 2- (2-ethoxyethoxy) ethanol
- ether solvents such as 2- (2-butoxyethoxy) ethanol
- amide solvents such as 2-pyrrolidone, N-methylpyrrolidone, dimethylformamide, and dimethylacetamide, ⁇ -butyrolactone, chlorobenzene, dimethylsulfoxide, and the like. These can be used alone or in combination of two or more.
- the composition is preferably prepared as a coating solution having a total solid content of 0.2% by mass or more, more
- the said composition for photo-alignment film formation prepared as a coating liquid is apply
- a known and commonly used method such as a spin coating method, a gravure printing method, a flexographic printing method, an ink jet method, a die coating method, a cap coating method, or dipping can be performed.
- the solution diluted with the organic solvent is applied, it is dried after application to obtain a coating film for a photo-alignment film.
- the coating film for photo-alignment film is irradiated with anisotropic light (hereinafter abbreviated as a photoisomerization step) to produce liquid crystal alignment ability to form a photo-alignment layer.
- anisotropic light used in the photoisomerization step include polarized light such as linearly polarized light and elliptically polarized light. Moreover, even if it is non-polarized light, you may irradiate from a diagonal direction with respect to the coating-film surface.
- the polarized light used in the photoisomerization step may be either linearly polarized light or elliptically polarized light, but in order to perform photoalignment efficiently, it is preferable to use linearly polarized light having a high degree of polarization. Further, linearly polarized light can be obtained by passing light from a light source through a polarizing prism such as a polarizing filter, Glan Thompson, or Glan Taylor.
- the incident angle of the non-polarized light is preferably in the range of 10 ° to 80 ° with respect to the substrate normal line.
- the range of 20 ° to 60 ° is more preferable, and 45 ° is most preferable.
- the aspect which irradiates non-polarized light from an oblique direction there is an advantage that a large irradiation intensity can be obtained without requiring a polarizing filter or the like in the light irradiation device, and the irradiation time for photo-alignment can be shortened.
- the wavelength of light to be irradiated is preferably in a wavelength region in which the photoactive group of the photoactive compound to be used has absorption.
- the photoactive group has an azobenzene structure
- ultraviolet light having a wavelength in the range of 330 to 500 nm, which has strong absorption due to the ⁇ ⁇ ⁇ * transition of azobenzene, is particularly preferable.
- the light source of the irradiation light include a xenon lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, and an ultraviolet laser such as KrF and ArF.
- an ultra-high pressure mercury lamp having particularly large emission intensity of ultraviolet light at 365 nm can be used effectively.
- the irradiated light is substantially parallel light regardless of whether polarized light or non-polarized light is used.
- liquid crystal alignment ability can be generated in two or more different directions in a pattern on the photo-alignment film. Specifically, after the composition for photo-alignment film is applied and dried, the substrate is covered with a photomask, and the entire surface is irradiated with polarized light or non-polarized light to give liquid crystal alignment ability to the exposed portion in a pattern. By repeating this a plurality of times as necessary, liquid crystal alignment ability can be generated in a plurality of directions.
- the photo-alignment film can be cooled after the photoisomerization step.
- the photo-isomerized coating film for the photo-alignment film may be cooled.
- the entire substrate is cooled by a known and common cooling device such as a cold plate, a chamber, or a low-temperature thermostat.
- the cooling condition is that the cooling temperature is 20 ° C. for 1 minute or longer, but this is not the case when the cooling temperature is lower than 20 ° C.
- the cooling temperature may be not lower than the melting point of the solvent to be used, but is usually preferably in the range of -40 ° C to 20 ° C.
- the temperature is preferably 10 ° C. or less, and the cooling time is preferably 5 minutes or more. In order to further shorten the cooling time, the cooling temperature is preferably 5 ° C. or lower.
- the cooling may be performed in a dry air, nitrogen, or argon atmosphere, or the substrate may be cooled while blowing dry air, nitrogen, or the like onto the substrate. In this way, a photo-alignment film can be formed.
- Coating step step of coating a coating solution of a dichroic dye composition dissolved in an organic solvent on an alignment-treated substrate or alignment film
- a coating solution of a dichroic dye composition dissolved in an organic solvent that is, an organic solvent solution of a dichroic dye
- the light absorption anisotropic film of the present invention can be formed using, for example, a coating solution of the dichroic dye composition of the present invention.
- a solvent used for preparation of a coating liquid an organic solvent is preferable.
- organic solvents include amides (eg N, N-dimethylformamide), sulfoxides (eg dimethyl sulfoxide), heterocyclic compounds (eg pyridine), hydrocarbons (eg benzene, hexane), alkyl halides (eg , Chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane). Alkyl halides and ketones are preferred. Two or more organic solvents may be used in combination.
- the dichroic dye composition coating solution is applied to the alignment film surface by a usual method (for example, spin coating method, wire bar coating method, extrusion coating method, direct gravure coating method, reverse gravure coating method, die coating method, Ink jet method, slit coating method, cap coating method, dipping, etc.).
- the total solid content in the dichroic dye composition coating solution is preferably 0.1 to 20% by mass, more preferably 0.1 to 10% by mass, and further preferably 0.5 to 5% by mass.
- the light absorption anisotropic film of the present invention is preferably formed by a wet film formation method.
- a coating liquid comprising the dichroic dye composition of the present invention is prepared, and then applied to various substrates such as a glass plate, and the dye is oriented and laminated.
- a known method such as a method is employed.
- the temperature at the time of application is preferably 0 ° C. or more and 80 ° C. or less, and the humidity is preferably about 10% RH or more and 80% RH or less.
- a substrate such as a support may be heated or cooled.
- the temperature of the base material at this time is preferably 10 ° C. or higher and 60 ° C. or lower. If the upper limit is exceeded, the orientation may be disturbed before drying under reduced pressure, which will be described in detail below, and if it is lower than the lower limit, water droplets may adhere to the substrate surface, which may hinder coating.
- the substrate may be heated when the dye film applied by the wet film forming method is dried under reduced pressure.
- the temperature of the base material at this time is preferably 60 ° C. or lower. If the upper limit is exceeded, the orientation may be disturbed before drying under reduced pressure.
- the light absorption anisotropic film of the present invention when used as a polarizing filter or the like for various display elements such as LCD and OLED, a dye film is directly formed on an electrode substrate or the like constituting these display elements, A substrate on which a dye film is formed can be used as a constituent member of these display elements.
- the light-absorbing property is obtained by coating the dichroic dye composition of the present invention on a substrate that has been aligned in one direction at an angle that is not parallel to the alignment direction on the substrate.
- An anisotropic film can be formed.
- the dichroic dye composition of the present invention is described in, for example, JP-A-2007-127897.
- Drying and orientation step step of orienting the dichroic dye composition by evaporating the organic solvent
- the drying temperature is preferably natural drying at room temperature, and it is preferable not to disturb the alignment state of the dye formed by coating (avoid thermal relaxation or the like). It is more preferable to evaporate the solvent and dry at a lower temperature in the reduced pressure treatment.
- the decompression treatment here means that the coating film (light absorption anisotropic film) is placed under a decompression condition and the solvent is removed by evaporation.
- the base material having the light absorption anisotropic film is preferably horizontal so that it does not flow from the high part to the bottom part.
- the time is preferably from 1 second to 30 seconds.
- Examples of the decompression method include the following methods.
- the light absorption anisotropic film obtained by applying the coating solution on the substrate is put into a reduced pressure processing apparatus and subjected to reduced pressure processing.
- a decompression processing apparatus as shown in FIGS. 9 and 10 of JP-A-2006-201759 can be used. Details of the decompression processing apparatus are described in JP-A No. 2004-169975.
- the pressure in the system where the dye film is present is preferably 2 ⁇ 10 4 Pa or less, more preferably 1 ⁇ 10 4 Pa or less, and particularly preferably 1 ⁇ 10 3 Pa or less. Moreover, Preferably it is 1 Pa or more, More preferably, it is 1 * 10 ⁇ 1 > Pa or more.
- the pressure finally reached in the system is preferably as described above. If the upper limit is exceeded, drying may not be possible and the orientation may be disturbed. If the lower limit is not reached, drying may be too rapid and defects may occur.
- the decompression time is preferably 5 seconds or more and 180 seconds or less. If the upper limit is exceeded, the dye film cannot be dried quickly before orientation relaxation, and the orientation may be disturbed. If the lower limit is not reached, drying may not be possible and the orientation may be disturbed.
- the temperature in the system during the decompression treatment is preferably 10 ° C. or more and 60 ° C. or less. If the value exceeds the upper limit, convection may occur during drying, resulting in the occurrence of non-uniformity in the coating film. If the value is less than the lower limit, the film cannot be dried and orientation may be disturbed.
- the thickness of the light absorption anisotropic film after drying is preferably from 0.01 to 30 ⁇ m, more preferably from 0.01 to 10 ⁇ m, and further preferably from 0.05 to 5 ⁇ m.
- the light absorption anisotropic film referred to in the present invention is anisotropic in electromagnetic properties in any two directions selected from a total of three directions in the thickness direction of the dye film and any two orthogonal in-plane three-dimensional coordinate systems. It is a dye film having properties.
- electromagnetic properties include optical properties such as absorption and refraction, and electrical properties such as resistance and capacitance.
- film having optical anisotropy such as absorption and refraction include a linear polarizing film, a circular polarizing film, a retardation film, and a resistivity anisotropic film.
- the light absorption anisotropic film of the present invention can be used for a polarizing film, a retardation film, or a resistivity anisotropic film.
- the light absorption anisotropic film of the present invention exhibits a high absorbance over the entire visible light region, and thus is useful as a polarizing film.
- the light absorption anisotropic film of the present invention is characterized in that it exhibits a diffraction peak derived from a periodic structure in the in-plane direction in X-ray diffraction measurement, and its half-value width is 1.0 mm or less.
- the half-width indicates the intensity of the peak apex with respect to the baseline in one diffraction peak of the X-ray diffraction measurement, and one half of the intensity at the left and right of the peak apex. It is a value obtained by taking two points and taking the difference between the values of the periods indicated by the two points.
- the light absorption anisotropic film of the present invention which shows a diffraction peak derived from a periodic structure in the in-plane direction of the film and has a half width of 1.0 mm or less, For this reason, it is estimated that a high dichroic ratio is exhibited.
- the light absorption anisotropic film exhibits a higher dichroic ratio as the angle between the molecular long axis of the dichroic dye and the orientation axis is smaller on average and the variation is smaller.
- the orientation axis means the direction in which the light absorption anisotropic film exhibits the greatest absorbance with respect to linearly polarized light, and usually coincides with the direction in which the orientation treatment is performed.
- Specific examples of the alignment treatment include methods such as stretching of a resin film dyed with a dichroic dye, rubbing of an alignment film, irradiation of linearly polarized light, application of an electric field / magnetic field, as already described in detail. As described above, the present invention is not limited to these methods.
- the variation in the angle between the molecular long axis and the orientation axis of the dichroic dye is large, the variation in the intermolecular distance also increases. Then, when there is a periodic structure, the value of the period also varies, and the diffraction peak obtained by X-ray diffraction measurement becomes broad and shows a large half-value width.
- the fact that the half-width of the diffraction peak is a sharp peak is a certain value or less means that the variation in intermolecular distance is small and the dichroism is small. It means that the angle formed by the molecular long axis of the dye and the alignment axis is small on average, that is, highly oriented, and is assumed to exhibit a high dichroic ratio.
- a liquid crystalline dichroic dye compound or composition that exhibits a nematic phase is used, but usually or in the prior art, the dichroic ratio is as low as about 10 or less.
- the present inventors in the light absorption anisotropic film comprising the novel dichroic dye-containing composition of the present invention, have a light absorption anisotropy in which the half width of the diffraction peak is 1.0 mm or less. It has been found that the film is novel with a high dichroic ratio.
- the half width of the diffraction peak of the light absorption anisotropic film of the present invention is thus at least 1.0 mm or less, preferably 0.90 mm or less, more preferably 0.70 mm or less, further preferably 0.50 mm or less. Yes, preferably 0.1 mm or more.
- the full width at half maximum exceeds the upper limit, the variation in the intermolecular distance of the dye increases, which is not preferable because highly ordered orientation is inhibited.
- the value is below the lower limit, orientation distortion tends to occur and domains and grain boundaries are generated, which may cause haze and disorder of orientation for each domain.
- the period represented by the diffraction peak in X-ray diffraction measurement is preferably 3.5 to 10.0 mm, more preferably 3.5 to 8.5 mm. 0 to 7.0 mm is more preferable, and 4.5 to 6.0 mm is most preferable.
- the “period” represented by the diffraction peak is considered to correspond to the intermolecular distance of the dye.
- the period and half-value width of the diffraction peak of the light absorption anisotropic film are measured with an X-ray diffractometer for thin film evaluation (trade name: “ATX-G” in-plane optical system manufactured by Rigaku Corporation) or an equivalent device.
- these are obtained, for example, by the following procedure.
- the in-plane measurement in all directions is performed for the light-absorbing anisotropic film in increments of 15 °.
- the orientation in the substrate plane where the peak intensity is large is determined by so-called ⁇ scan in which the sample is rotated and measured in a plane parallel to the substrate while the angle at which the peak is observed is fixed.
- ⁇ scan in which the sample is rotated and measured in a plane parallel to the substrate while the angle at which the peak is observed is fixed.
- the period and the half width were obtained.
- the dye film comprising the oriented dichroic dye of the present invention is a light absorption anisotropic dye film having anisotropy of light absorption, and is characterized by the half width and period of the diffraction peak.
- An element (polarizing element) having a function as a polarizing film with high attached characteristics can be formed.
- the formed anisotropic dye film itself may be used as a polarizing element, and a protective layer, an adhesive layer, and an antireflection layer may be further formed.
- a transparent electrode such as ITO is formed on the support (substrate) in the steps (1) to (3) described above.
- An anisotropic dye film may be formed on the electrode.
- polarizing film may be formed on the electrode.
- the dichroic dye composition of the present invention when the coating liquid comprising the dichroic dye composition of the present invention is applied onto the alignment film, the dichroic dye is aligned at the tilt angle of the alignment film at the interface with the alignment film, and at the air interface at the interface with air.
- Orientation at a tilt angle of Horizontal orientation can be realized by applying the dichroic dye composition coating liquid of the present invention to the surface of the alignment film and then orienting the dichroic dye uniformly (monodomain orientation).
- a light absorption anisotropic film formed by horizontally aligning a dichroic dye and fixing the dichroic dye in the aligned state can be used as a polarizing element.
- the tilt angle refers to an angle formed between the major axis direction of the molecule of the dichroic dye and the interface (alignment film interface or air interface).
- Optical performance preferable as a polarizing element can be more effectively obtained by reducing the tilt angle on the alignment film side to some extent and performing horizontal alignment. Therefore, from the viewpoint of polarization performance, the preferred tilt angle on the alignment film side is 0 ° to 10 °, more preferably 0 ° to 5 °, particularly preferably 0 ° to 2 °, and most preferably 0 ° to 1 °. is there.
- the tilt angle on the air interface side is preferably 0 ° to 10 °, more preferably 0 to 5 °, and particularly preferably 0 to 2 °.
- the tilt angle of the dichroic dye on the air interface side is determined by other compounds added as desired (for example, JP-A-2005-99248, JP-A-2005-134484, JP-A-2006-126768). And a horizontal alignment agent described in JP-A-2006-267183, etc.), and can be adjusted as a polarizing element of a liquid crystal display device to which the light absorption anisotropic film of the present invention is applied. An alignment state can be realized. Further, the tilt angle of the dichroic dye on the alignment film side can be controlled by the above-described method (alignment film tilt angle control agent or the like).
- the thus formed light-absorbing anisotropic film of the present invention functions as a polarizing film that obtains linearly polarized light, circularly polarized light, elliptically polarized light, etc. by utilizing the anisotropy of light absorption.
- the formed light absorption anisotropic film of the present invention When the light absorption anisotropic film of the present invention is formed on a substrate and used as a polarizing element, the formed light absorption anisotropic film itself may be used.
- the protective layer Function as adhesive layer or antireflection layer, alignment film, retardation film, function as brightness enhancement film, function as reflection film, function as transflective film, function as diffusion film, function as optical compensation film
- a layer having various functions, such as a layer having an optical function may be laminated by a wet film formation method or the like, and used as a laminate. These layers having optical functions can be formed, for example, by the following method.
- the layer having a function as a retardation film is subjected to, for example, a stretching process described in Japanese Patent No. 2841377, Japanese Patent No. 3094113, or a process described in Japanese Patent No. 3168850. Can be formed.
- the layer having a function as a brightness enhancement film may be formed by forming fine holes by a method described in, for example, Japanese Patent Application Laid-Open No. 2002-169025 and Japanese Patent Application Laid-Open No. 2003-29030, or selective reflection. It can be formed by superposing two or more cholesteric liquid crystal layers having different center wavelengths.
- the layer having a function as a reflective film or a transflective film can be formed using a metal thin film obtained by vapor deposition or sputtering.
- the layer having a function as a diffusion film can be formed by coating the protective layer with a resin solution containing fine particles.
- the layer having a function as a retardation film or an optical compensation film can be formed by coating and aligning a liquid crystal compound such as a discotic liquid crystal compound.
- the liquid crystal display device of the present invention is particularly limited as long as it has a light absorption anisotropic film, a polarizing element and the like produced using the dichroic dye composition and utilizes the liquid crystallinity.
- specific examples include a television display, a PC display, an in-vehicle display, and an outdoor display.
- Dichroic ratio (D) Az / Ay Az: Absorbance with respect to polarized light in the absorption axis direction of the light absorption anisotropic film
- Ay Absorbance with respect to polarization in the polarization axis direction of the light absorption anisotropic film
- the full width at half maximum was obtained from an in-plane measurement profile using a thin film evaluation X-ray diffractometer (trade name: “ATX-G” in-plane optical system, manufactured by Rigaku Corporation) and a ⁇ scan profile. Both measurements were performed using CuK ⁇ at an incident angle of 0.18 °.
- Example 1 2 parts by weight of the exemplified dye (A-46) was stirred and dissolved in 98 parts by weight of chloroform to obtain a dye solution for an optically anisotropic film (coating liquid).
- the dye solution was applied by spin coating on a glass substrate with a polyvinyl alcohol alignment film (trade name: PVA-103, manufactured by Nissan Chemical Industries, Ltd.) subjected to homogeneous alignment treatment by rubbing and naturally dried, and then 70 ° C. For 1 minute to obtain a light absorption anisotropic film.
- the thickness of the film was 0.2 ⁇ m.
- FIG. 1 shows X-ray diffraction patterns obtained from the direction perpendicular to the orientation axis of the film (the direction in which the diffraction plane perpendicular to the transmission axis is observed) and the orientation axis direction (the direction in which the diffraction plane perpendicular to the absorption axis is observed). . Two peaks were detected in the direction perpendicular to the orientation axis and two in the orientation axis direction. Table 1 shows the period and half-value width obtained from each peak.
- Example 2 2 parts by weight of the exemplified dye (A-58) was stirred and dissolved in 98 parts by weight of chloroform to obtain a dye solution for a light-absorbing anisotropic film.
- the dye solution (coating solution) was spin-coated on a glass substrate with a polyvinyl alcohol alignment film (trade name: PVA-103, manufactured by Nissan Chemical Industries, Ltd.) subjected to homogeneous alignment treatment by rubbing and allowed to dry naturally. Then, it heated at 40 degreeC for 1 hour, and obtained the light absorption anisotropic film. The thickness of the film was 0.2 ⁇ m.
- the obtained light absorption anisotropic film had a dichroic ratio of 18.
- Table 2 shows X-ray diffraction patterns obtained from the direction perpendicular to the orientation axis and the orientation axis direction of the film. Four peaks were detected in the direction perpendicular to the alignment axis and one peak in the alignment axis direction. Table 2 shows the period and half-value width obtained from each peak.
- Example 3 2 parts by weight of the exemplified dye (C-10) was stirred and dissolved in 98 parts by weight of chloroform to obtain a dye solution for a light-absorbing anisotropic film.
- the dye solution (coating solution) was spin-coated on a glass substrate with a polyvinyl alcohol alignment film (trade name: PVA-103, manufactured by Nissan Chemical Industries, Ltd.) subjected to homogeneous alignment treatment by rubbing and allowed to dry naturally. Then, it heated at 40 degreeC for 1 hour, and obtained the light absorption anisotropic film. The thickness of the film was 0.2 ⁇ m.
- the obtained light absorption anisotropic film had a dichroic ratio of 18.
- Table 3 shows X-ray diffraction patterns obtained from the direction perpendicular to the orientation axis and the orientation axis direction of the film. Two peaks were detected in the direction perpendicular to the alignment axis. Table 3 shows the period and half width obtained from each peak.
- Example 4 2 parts by weight of the exemplified dye (D-2) was stirred and dissolved in 98 parts by weight of chloroform to obtain a dye solution for a light-absorbing anisotropic film.
- the dye solution (coating solution) was spin-coated on a glass substrate with a polyvinyl alcohol alignment film (trade name: PVA-103, manufactured by Nissan Chemical Industries, Ltd.) that had been subjected to homogeneous alignment treatment by rubbing and allowed to dry naturally. Then, it heated at 40 degreeC for 1 hour, and obtained the light absorption anisotropic film. The thickness of the film was 0.2 ⁇ m.
- the dichroic ratio of the obtained light absorption anisotropic film was 19.
- Table 4 shows X-ray diffraction patterns obtained from the direction perpendicular to the orientation axis and the orientation axis direction of the film. Two peaks were detected in the direction perpendicular to the alignment axis. Table 4 shows the period and half-value width obtained from each peak.
- each of the light absorption anisotropic films of this example had a molecular arrangement suitable for dichroic ratio expression and exhibited a high dichroic ratio.
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Abstract
Description
例えば、LCD(液晶素子)では表示における旋光性や複屈折性を制御するために直線偏光板や円偏光板が用いられている。OLED(有機エレクトロルミネッセンス素子)においても外光の反射防止のために円偏光板が使用されている。従来、これらの偏光板(偏光素子)にはヨウ素が二色性物質として広く使用されてきた。しかしながら、ヨウ素は昇華性が大きいために偏光素子に使用した場合、その耐熱性や耐光性が十分ではなかった。また、その消光色が深い青になり、全可視スペクトル領域にわたって理想的な無彩色偏光素子とは言えなかった。
また本発明は本発明者らの見いだしたかかる知見に基づいてなされるに至ったものである。
〔1〕X線回折測定において膜面内方向の周期構造に由来する回折ピークを示し、その半値幅が1.0Å以下であることを特徴とする二色性色素の少なくとも一種を有する光吸収異方性膜。
〔2〕前記回折ピークが配向軸垂直方向の周期構造に由来する、〔1〕に記載の光吸収異方性膜。
〔3〕前記回折ピークが表す周期が3.5~10.0Åである、〔1〕または〔2〕に記載の光吸収異方性膜。
〔4〕膜厚が0.01~30μmである、〔1〕~〔3〕のいずれかに記載の光吸収異方性膜。
〔5〕配向膜上に形成されたことを特徴とする、〔1〕~〔4〕のいずれかに記載の光吸収異方性膜。
〔6〕前記二色性色素として、下記一般式(I)で表されるアゾ色素を含有し、かつ、液晶性を有する、〔1〕~〔5〕のいずれかに記載の光吸収異方性膜を形成するための二色性色素組成物。
〔7〕前記一般式(I)で表されるアゾ色素が、下記一般式(Ia)で表される化合物であることを特徴とする〔6〕に記載の二色性色素組成物。
〔10〕〔9〕に記載の偏光素子を用いた表示装置。
〔11〕少なくとも
[1]基板を直接、又は該基板上に形成された配向膜をラビング、もしくは光照射する工程と、
[2]該基板又は該配向膜上に、〔6〕~〔8〕のいずれかに記載の二色性色素組成物を塗布する工程と、
[3]該二色性色素組成物中を配向させ偏光素子とする工程
をこの順に含む〔9〕に記載の偏光素子の製造方法。
(二色性色素)
本発明の二色性色素組成物における二色性色素は、液晶性を有する限り二色性色素としては特に制限はなく、例えば、アゾ系色素、シアニン系色素、アゾ金属錯体、フタロシアニン系色素、ピリリウム系色素、チオピリリウム系色素、アズレニウム系色素、スクワリリウム系色素、キノン系色素、トリフェニルメタン系色素、及びトリアリルメタン系色素等を挙げることができる。好ましくは、アゾ系色素またはアゾ金属錯体である。本発明において、「二色性色素」とは、方向によって吸光度が異なる色素を意味する。
また、「二色性」および「二色比」は、二色性色素組成物を光吸収異方性膜としたときの、偏光軸方向の偏光の吸光度に対する、吸収軸方向の偏光の吸光度の比で計算される。
本発明における二色性色素組成物は、下記一般式(I)で表されるアゾ色素の少なくとも一種を含有することが特に好ましい。
アルキル基(好ましくは炭素数1~20、より好ましくは炭素数1~12、特に好ましくは炭素数1~8のアルキル基であり、例えば、メチル基、エチル基、イソプロピル基、tert-ブチル基、n-オクチル基、n-デシル基、n-ヘキサデシル基、シクロプロピル基、シクロペンチル基、シクロヘキシル基などが挙げられる)、アルケニル基(好ましくは炭素数2~20、より好ましくは炭素数2~12、特に好ましくは炭素数2~8のアルケニル基であり、例えば、ビニル基、アリール基、2-ブテニル基、3-ペンテニル基などが挙げられる)、アルキニル基(好ましくは炭素数2~20、より好ましくは炭素数2~12、特に好ましくは炭素数2~8のアルキニル基であり、例えば、プロパルギル基、3-ペンチニル基などが挙げられる)、アリール基(好ましくは炭素数6~30、より好ましくは炭素数6~20、特に好ましくは炭素数6~12のアリール基であり、例えば、フェニル基、2,6-ジエチルフェニル基、3,5-ジトリフルオロメチルフェニル基、ナフチル基、ビフェニル基などが挙げられる)、置換もしくは無置換のアミノ基(好ましくは炭素数0~20、より好ましくは炭素数0~10、特に好ましくは炭素数0~6のアミノ基であり、例えば、無置換アミノ基、メチルアミノ基、ジメチルアミノ基、ジエチルアミノ基、アニリノ基などが挙げられる)、
これらの置換基はさらにこれらの置換基によって置換されていてもよい。また、置換基が二つ以上有する場合は、同じでも異なってもよい。また、可能な場合には互いに結合して環を形成していてもよい。
該フェニル基又は該ナフチル基が有していてもよい置換基としては、アゾ化合物の溶解性やネマチック液晶性を高めるために導入される基、色素としての色調を調節するために導入される電子供与性や電子吸引性を有する基、又は配向を固定化するために導入される重合性基を有する基が好ましく、具体的には、前記R1~R4で表される置換基と同義である。好ましくは、置換基を有していてもよいアルキル基、置換基を有していてもよいアルケニル基、置換基を有していてもよいアルキニル基、置換基を有していてもよいアリール基、置換基を有していてもよいアルコキシ基、置換基を有していてもよいオキシカルボニル基、置換基を有していてもよいアシルオキシ基、置換基を有していてもよいアシルアミノ基、置換基を有していてもよいアミノ基、置換基を有していてもよいアルコキシカルボニルアミノ基、置換基を有していてもよいスルホニルアミノ基、置換基を有していてもよいスルファモイル基、置換基を有していてもよいカルバモイル基、置換基を有していてもよいアルキルチオ基、置換基を有していてもよいスルホニル基、置換基を有していてもよいウレイド基、ニトロ基、ヒドロキシ基、シアノ基、イミノ基、アゾ基、ハロゲン原子であり、特に好ましくは、置換基を有していてもよいアルキル基、置換基を有していてもよいアルケニル基、置換基を有していてもよいアリール基、置換基を有していてもよいアルコキシ基、置換基を有していてもよいオキシカルボニル基、置換基を有していてもよいアシルオキシ基、ニトロ基、イミノ基、アゾ基である。これらの置換基のうち、炭素原子を有するものについては、炭素原子数の好ましい範囲は、R1~R4で表される置換基についての炭素原子数の好ましい範囲と同様である。
該芳香族複素環基が有していてもよい置換基としては、メチル基、エチル基等のアルキル基、メトキシ基、エトキシ基等のアルコキシ基、無置換あるいはメチルアミノ基等のアミノ基、アセチルアミノ基、アシルアミノ基、ニトロ基、ヒドロキシ基、シアノ基、ハロゲン原子等が挙げられる。これらの置換基のうち、炭素原子を有するものについては、炭素原子数の好ましい範囲は、R1~R4で表される置換基についての炭素原子数の好ましい範囲と同様である。
重合性基としては特に限定されないが、重合反応は、付加重合(開環重合を含む)または縮合重合であることが好ましい。換言すれば、重合性基は付加重合反応または縮合重合反応が可能な重合性基であることが好ましい。
以下に重合性基の具体例を示すが、本発明はこれに限定されない。なお、式中、Etはエチル基、Prはプロピル基を表す。
本発明においては、重合性基としては、ラジカル重合性基が特に好ましい。
重合性基は分子末端に位置するのが好ましく、即ち、式(I)中では、R5及び/又はR6の置換基として、並びにA1の置換基として、存在するのが好ましい。
このようにして、本発明において、上記(I)で表される二色性色素の少なくとも一種を含有する二色性色素組成物は、液晶性を有するものとなる。
さらに、前記一般式(I)で表されるアゾ色素は、分子の平面性が高いため強い分子間相互作用が働き、分子同士が会合状態を形成しやすい性質も有している。
本発明の二色性色素組成物は、後述する実施例に記載の方法で算出した二色比(D)を15以上に高めることができ、好ましい(D)は18以上である。
本発明の一般式(Ia)で表わされるアゾ色素は、マゼンタのアゾ色素であり、一般式(Ib)で表わされるアゾ色素は、イエロー又はマゼンタのアゾ色素であり、一般式(Ic)で表わされるアゾ色素は、シアンのアゾ色素である。
前記二色性色素組成物が含有する2種以上の一般式(I)で表されるアゾ色素のうち、少なくとも1種は、一般式(Ia)で表されるアゾ色素であることが好ましい。
また、前記二色性色素組成物は、一般式(Ib)又は(Ic)で表されるアゾ色素を含有することが好ましい。
また、前記二色性色素組成物は、少なくとも1種の一般式(Ia)で表されるアゾ色素、及び少なくとも1種の一般式(Ib)又は(Ic)で表されるアゾ色素を含有することが好ましい。
また、前記二色性色素組成物は、少なくとも1種の一般式(Ia)で表されるアゾ色素、少なくとも1種の一般式(Ib)で表される化合物、及び少なくとも1種の(Ic)で表されるアゾ色素を含有しているのがさらに好ましい。
なお、前記二色性色素組成物は、本発明の効果を損なわない範囲で、一般式(I)で表されるアゾ色素以外の色素等である着色材料をさらに含有していてもよい。一般式(I)で表されるアゾ色素以外の色素も、液晶性を示す化合物から選択されるのが好ましい。併用可能な色素としては、例えば、「Dichroic Dyes for Liquid Crystal Display」(A. V. Ivashchenko著、CRC社、1994年)に記載のものを用いることができる。
本発明に用いる前記二色性色素組成物は、1種以上のアゾ色素とともに、界面活性剤を含有していてもよい。界面活性剤は、当該組成物を塗布液として調製し、塗布する際に、塗布時の風ムラ等を防止することを目的として添加されるであろう。該界面活性剤としては、一般にフッ素系ポリマーを好適に用いることができる。使用するフッ素系ポリマーとしては、色素のチルト角変化や配向を著しく阻害しない限り、特に制限はない。界面活性剤として使用可能なフッ素ポリマーの例としては、特開2004-198511号公報、特許第4190275号公報、特開2004-333852号公報、特開2005-206638号公報、特願2008-193565号公報に記載がある。色素とフッ素系ポリマーとを併用することによって、ムラを生じることなく表示品位の高い画像を表示することができる。さらに、ハジキなどの塗布性も改善される。
前記アゾ色素の配向を阻害しないという観点では、風ムラ防止目的で使用される界面活性剤の添加量は、前記アゾ色素に対して一般に0.1~10質量%程度であるのが好ましく、0.5~10質量%程度であるのがより好ましく、0.5~5質量%程度であるのがさらに好ましい。
前記二色性色素組成物は、ラジカル重合性基を有する非液晶性の多官能モノマーを含有することが好ましい。
本発明において、「ラジカル重合性基を有する非液晶性の多官能モノマー」とは、成長活性種がラジカル的に重合反応する多官能モノマーであって、非液晶性のモノマーをいう。この多官能モノマーは分子内に2個以上の二重結合を有する多官能モノマーであることが好ましく、エチレン性(脂肪族性)不飽和二重結合であることが特に好ましく、具体的には、アルケン、ジエン、アクリレート、メタクリレート、不飽和多価カルボン酸のジエステル、α、β-不飽和カルボン酸のアミド、不飽和ニトリル、スチレン及びその誘導体、ビニルエステル、ビニルエーテル等の官能基を有する多官能モノマーを挙げることができる。分子内の二重結合の数は、2~20であることが好ましく、2~15であることがさらに好ましく、2~6であることがより好ましい。多官能モノマーは、分子内に2個以上のヒドロキシルを有するポリオールと、不飽和脂肪酸とのエステルであることが好ましい。不飽和脂肪酸の例には、アクリル酸、メタクリル酸、マレイン酸及びイタコン酸が含まれ、アクリル酸及びメタクリル酸が好ましい。分子内に4個以上のヒドロキシルを有するポリオールは、四価以上のアルコールであるか、あるいは三価以上のアルコールのオリゴマーであることが好ましい。オリゴマーは、エーテル結合、エステル結合又はウレタン結合により多価アルコールを連結した分子構造を有する。多価アルコールをエーテル結合で連結した分子構造を有するオリゴマーが好ましい。
そのようなモノマーとしては、沸点が常圧で100度以上の化合物を挙げることができる。
ラジカル重合性基を有する非液晶性の多官能モノマーを含有する組成物では、該モノマーを硬化反応させるために、重合開始剤を含有することが好ましい。
重合開始剤としては、光重合、熱重合に応じて、公知のものを好適に使用することができ、たとえば光重合開始剤の例には、α-カルボニル化合物(米国特許2367661号、同2367670号の各明細書記載)、アシロインエーテル(米国特許2448828号明細書記載)、α-炭化水素置換芳香族アシロイン化合物(米国特許2722512号明細書記載)、多核キノン化合物(米国特許3046127号、同2951758号の各明細書記載)、トリアリールイミダゾールダイマーとp-アミノフェニルケトンとの組み合わせ(米国特許3549367号明細書記載)、アクリジン及びフェナジン化合物(特開昭60-105667号公報、米国特許4239850号明細書記載)及びオキサジアゾル化合物(米国特許4212970号明細書記載)が含まれる。
また、通常の光重合開始剤の吸収帯よりも長波長の光を吸収し、重合開始剤へのエネルギー移動を起こすことによって重合反応を誘起する化合物を混合してもよい。該化合物の混合により、光配向操作により固定されている光配向膜用組成物の配向状態を乱さずに、前記二色性色素組成物の重合を進行させることができる。一方、前記二色性色素組成物の重合を開始させるために、光配向操作と同一の方向から光照射する場合や、光活性化合物の吸収遷移モーメントと直交する偏波面を有する偏光照射を行えば、光配向膜層の配向状態を乱す恐れがないので、任意の波長の光を使用することができ、また重合開始剤の選択の幅も広がる。
320nm以下の紫外光で使用できる光重合開始剤としては1-ヒドロキシシクロヘキシルフェニルケトン(チバ・スペシャルティ・ケミカルズ社製、商品名「イルガキュア184」)、1-[4-(2-ヒドロキシエトキシ)-フェニル]-2-ヒドロキシ-2-メチル-1-プロパン-1-オン、2-ヒドロキシ-2-メチル-1-フェニルプロパン-1-オン(メルク社製、商品名「ダロキュア1173」)などが挙げられる。
また、アゾベンゼン骨格が有する光の吸収帯とは異なる光吸収波長帯域を持つ光重合開始剤としては、例えば、特許第3016606号に記載の近赤外線吸収色素と有機ホウ素を組み合わせたもの等が挙げられる。
その他の光重合開始剤としては、例えば、1-(4-イソプロピルフェニル)-2-ヒドロキシ-2-メチルプロパン-1-オン(メルク社製、商品名「ダロキュア1116」)、2-メチル-1-[(メチルチオ)フェニル]-2-モリホリノプロパン-1(チバ・スペシャルティ・ケミカルズ社製、商品名「イルガキュア907」)、ベンジルメチルケタ-ル(チバ・スペシャルティ・ケミカルズ社製「イルガキュア651」)、2,4-ジエチルチオキサントン(日本化薬社製、商品名「カヤキュアDETX」)とp-ジメチルアミノ安息香酸エチル(日本化薬社製、商品名「カヤキュアEPA」)との混合物、イソプロピルチオキサントン(ワ-ドプレキンソップ社製、商品名「カンタキュア-ITX」)とp-ジメチルアミノ安息香酸エチルとの混合物、アシルフォスフィンオキシド(BASF社製、商品名「ルシリンTPO」)、などが挙げられる。
また、熱重合の際に使用する熱重合開始剤としては公知慣用のものが使用でき、例えば、メチルアセトアセテイトパ-オキサイド、キュメンハイドロパ-オキサイド、ベンゾイルパ-オキサイド、ビス(4-t-ブチルシクロヘキシル)パ-オキシジカ-ボネイト、t-ブチルパ-オキシベンゾエイト、メチルエチルケトンパ-オキサイド、1,1-ビス(t-ヘキシルパ-オキシ)3,3,5-トリメチルシクロヘキサン、p-ペンタハイドロパ-オキサイド、t-ブチルハイドロパ-オキサイド、ジクミルパ-オキサイド、イソブチルパ-オキサイド、ジ(3-メチル-3-メトキシブチル)パ-オキシジカ-ボネイト、1,1-ビス(t-ブチルパ-オキシ)シクロヘキサン等の有機過酸化物、2,2’-アゾビスイソブチロニトリル、2,2’-アゾビス(2,4-ジメチルバレロニトリル)等のアゾニトリル化合物、2,2’-アゾビス(2-メチル-N-フェニルプロピオン-アミヂン)ジハイドロクロライド等のアゾアミヂン化合物、2,2’アゾビス{2-メチル-N-[1,1-ビス(ヒドロキシメチル)-2-ヒドロキシエチル]プロピオンアミド}等のアゾアミド化合物、2,2’アゾビス(2,4,4-トリメチルペンタン)等のアルキルアゾ化合物等を使用することができる。
光重合開始剤の例、光重合開始剤の使用量、及び重合のための光照射エネルギーの値の各々については、特開2001-91741号公報の段落[0050]~[0051]の記載も本発明に適用できる。
本発明で用いる前記二色性色素組成物には、上記1種以上のネマチック液晶性アゾ色素、並びに所望により添加される、界面活性剤、ラジカル重合性基を有する非液晶性の多官能モノマー、及び重合開始剤の他に、任意の添加剤を配合・併用することができる。添加剤の例としては、非液晶性のバインダーポリマー、ハジキ防止剤、配向膜のチルト角(偏光層/配向膜界面での液晶性アゾ色素のチルト角)を制御するための添加剤、空気界面のチルト角(偏光層/空気界面での液晶性アゾ色素のチルト角)を制御するための添加剤、糖類、防黴、抗菌及び殺菌の少なくともいずれかの機能を有する薬剤等である。以下、各添加剤について説明する。
本発明で用いる前記二色性色素組成物には、非液晶性バインダーポリマーを添加してもよい。非液晶性ポリマーの例として、ポリアクリロニトリル、ポリアクリル酸エステル、ポリアクリルアミド等のアクリル系樹脂、ポリスチレン樹脂、ポリビニルアセトアセタール、ポリビニルブチラールなどのポリビニルアセタール系樹脂、エチルセルロース、ヒドロキシエチルセルロース、エチルヒドロキシセルロース、ヒドロキシプロピルセルロース、エチルヒドロキシエチルセルロース、メチルセルロース、酢酸セルロース、酢酪酸セルロース、酢酸プロピオン酸セルロース、硝酸セルロース等の変性セルロース系樹脂ニトロセルロース、エチルヒドロキシエチルセルロース及びエチルセルロースなどのセルロース系樹脂や、ポリウレタン樹脂、ポリアミド樹脂、ポリエステル樹脂、ポリカーボネート樹脂、フェノキシ樹脂、フェノール樹脂、エポキシ樹脂、各種エストラマー等が挙げられる。これらは単独で用いても、2種以上を混合、もしくは共重合して用いることも可能である。
非液晶性のバインダーポリマーとしては、特にアクリル系ポリマー(アクリル系共重合体、スチレン系共重合体を主鎖とする樹脂)が好ましく、有機溶剤に可溶であることが特に好ましい。
これらは、1種単独で或いは2種以上を組み合わせて用いることができる。
本発明で用いる前記二色性色素組成物中には、塗布時のハジキを防止するための材料として、高分子化合物を添加することができる。この目的で使用する高分子化合物としては、当該液晶性アゾ色素と相溶性を有し、色素のチルト角変化や配向を著しく阻害しない限り、特に制限はない。ハジキ防止剤として使用可能なポリマーの例としては、特開平8-95030号公報に記載があり、特に好ましい具体的ポリマー例としてはセルロースエステル類を挙げることができる。セルロースエステルの例としては、セルロースアセテート、セルロースアセテートプロピオネート、ヒドロキシプロピルセルロース及びセルロースアセテートブチレートを挙げることができる。アゾ色素の配向を阻害しないように、ハジキ防止目的で使用されるポリマーの添加量は、前記液晶性アゾ色素に対して一般に0.1~10質量%の範囲であるのが好ましく、0.1~8質量%の範囲にあるのがより好ましく、0.1~5質量%の範囲にあるのがさらに好ましい。
前記二色性色素組成物には、配向膜側の前記液晶性アゾ色素分子のチルト角を制御する添加剤を添加してもよい。この様な作用を有する添加剤の例には、分子内に極性基と非極性基の両方を有する化合物が含まれる。分子内に極性基と非極性基の両方を有する化合物としては、PO-OH、PO-COOH、PO-O-PO、PO-NH2、PO-NH-PO、PO-SH、PO-S-PO、PO-CO-PO、PO-COO-PO、PO-CONH-PO、PO-CONHCO-PO、PO-SO3H、PO-SO3-PO、PO-SO2NH-PO、PO-SO2NHSO2-PO、PO-C=N-PO、HO-P(-OPO)2、(HO-)2PO-OPO、P(-OPO)3、HO-PO(-OPO)2、(HO-)2PO-OPO、PO(-OPO)3、PO-NO2及びPO-CNならびにこれらの有機塩が好ましい例として挙げられる。ここで、有機塩としては、上記化合物の有機塩(例えば、アンモニウム塩、カルボン酸塩、スルホン酸塩等)の他、ピリジニウム塩等も好ましく採用することができる。前記分子内に極性基と非極性基の両方を有する化合物の中でも、PO-OH、PO-COOH、PO-O-PO、PO-NH2、PO-SO3H、HO-PO(-OPO)2、(HO-)2PO-OPO、PO(-OPO)3もしくはこれらの有機塩が好ましい。ここで、上記各POは非極性基を表し、POが複数ある場合は、それぞれ同一でも異なっていてもよい。
本発明では、特開2006-58801号公報に記載の配向膜チルト制御剤を使用することができる。
本発明に用いる前記二色性色素組成物は、空気界面チルト角制御剤として水平配向剤を含むことが好ましい。本発明では光配向膜層を利用しているので、光配向膜層との界面においてプレチルト角の特に小さい良好なホモジニアス配向構造を実現するが、プレチルト角の方向が制御されていないため、空気界面においてチルト角が生じた場合にその方向が一定とならず、リバースチルトドメインを生じる場合がある。空気界面チルト角制御剤を添加することで、空気界面における液晶性アゾ色素分子の配向を水平配向とし、リバースチルトドメインの発生を抑えることができる。
(1)下記一般式(III)で表されるフルオロ脂肪族基含有化合物;又は、
(2)一般式(IV)もしくは一般式(V)で表されるフルオロ脂肪族基含有モノマーの重合単位及び一般式(VI)で表されるアミド基含有モノマーの重合単位からなる群から選択される少なくとも一種の重合単位を含むフルオロ脂肪族基含有共重合体;
である。
以下、それぞれ説明する。まず、(1)一般式(III)で表されるフルオロ脂肪族基含有化合物について説明する。
R2:n-C6F13-O-
R3:n-C4F9-O-
R4:n-C8F17-(CH2)2-O-(CH2)2-O-
R5:n-C6F13-(CH2)2-O-(CH2)2-O-
R6:n-C4F9-(CH2)2-O-(CH2)2-O-
R7:n-C8F17-(CH2)3-O-
R8:n-C6F13-(CH2)3-O-
R9:n-C4F9-(CH2)3-O-
R10:H-(CF2)8-O-
R11:H-(CF2)6-O-
R12:H-(CF2)4-O-
R13:H-(CF2)8-(CH2)-O-
R14:H-(CF2)6-(CH2)-O-
R15:H-(CF2)4-(CH2)-O-
R16:H-(CF2)8-(CH2)-O-(CH2)2-O-
R17:H-(CF2)6-(CH2)-O-(CH2)2-O-
R18:H-(CF2)4-(CH2)-O-(CH2)2-O-
前記一般式(V)中、R52は、水素原子、ハロゲン原子又はメチル基を表し、水素原子又はメチル基がより好ましい。L52は2価の連結基を表し、n51は1以上18以下の整数を表し、2~12がより好ましく、4~8が更に好ましく、4又は6であることが最も好ましい。
(a)-X10-R20-(b)
一般式(VII)中、X10は単結合、又は*-COO-**、*-COS-**、*-OCO-**、*-CON(R21)-**、*-O-**で示される2価の連結基を表す。ここで*は二重結合側に結合する位置、**はR20に結合する位置を各々示す。
R20は、置換基を有していてもよいポリメチレン基(例えばメチレン基、エチレン基、トリメチレン基など)、置換基を有していてもよいフェニレン基(例えばo-フェニレン基、m-フェニレン基、p-フェニレン基など)、及びそれらの任意の組み合わせにより形成できる基を表す。中ではポリメチレン基がより好ましく、ポリメチレン基の中でもメチレン基、エチレン基、トリメチレン基、及びテトラメチレン基が好ましく、メチレン基及びエチレン基が更に好ましい。
R21は、水素原子又は炭素数1~8の置換基を有してもよいアルキル基、あるは炭素数6~20の置換基を有してもよいアリール基を表し、水素原子又は炭素数1~6のアルキル基がより好ましく、水素原子又は炭素数1~4のアルキル基が更に好ましい。
前記一般式(VI)中、R53は水素原子、ハロゲン原子又はメチル基を表し、水素原子又はメチル基がより好ましい。R60及びR61はそれぞれ独立に水素原子、炭素数1~18のアルキル基、炭素数6~20の芳香族基又は炭素数1~20のヘテロ環基を表し、これらの置換基はさらに置換基を有していてもよい。また、炭素数1~12のアルキル基、炭素数6~15の芳香族基であることがより好ましく、炭素数1~6のアルキル基、炭素数6~12の芳香族基であることがさらに好ましい。また、R60とR61が互いに連結して複素環を形成してもよく、形成されるヘテロ環の種類としては、ピロリジン環、ピペリジン環、モルホリン環などが挙げられる。
本発明で用いる二色性色素組成物には、糖類を添加してもよい。糖類を添加することにより色素会合体の会合度を向上させ、その結果として色素の分子配向を高めることができる。
使用可能な糖類としては、単糖、二糖、多糖、及び糖アルコール類などの糖の誘導体が挙げられる。糖類の中でも、本発明の効果を奏するにあたり、分子会合性の点から、水酸基が通常2以上、好ましくは3以上で、好ましくは18以下、更に好ましくは12以下であるものが良い。水酸基が多過ぎると色素との相互作用が強すぎて析出して色素膜の配向性を損ねてしまうので好ましくなく、少な過ぎると色素との相互作用が不十分であり配向性を向上させることができないので好ましくない。
単糖としては、例えばキシロース、リボース、グルコース、フルクトース、マンノース、ソルボース、ガラクトースなどが挙げられる。
オリゴ糖としては、例えばトレハロース、コウジビオース、ニゲロース、マルトース、マルトトリオース、イソマルトトリオース、マルトテトラオース、イソマルトース、ソホロース、ラミナリビオース、セロビオース、ゲンチオビオース、ラクトース、スクロース、メリビオース、ルチノース、プリメベロース、ツラノース、パノース、イソパノース、セロトリオース、マンニノトリオース、ソラトリオース、メレジトース、プランテオース、ゲンチアノース、ウンベリフェロース、ラフィノース、スタキオースなどが挙げられる。
糖アルコールとしては、例えばトレイトール、キシリトール、リビトール、アラビトール、ソルビトール、マンニトールなど前述の単糖及びオリゴ糖を還元した化合物が挙げられる。
本発明で用いる前記二色性色素組成物には、防黴、抗菌及び殺菌の少なくともいずれかの機能を有する薬剤を添加してもよい。これらの添加剤を添加することにより、当該組成物の保存安定性を向上させることができる。
なお、本明細書では、「防黴、抗菌及び殺菌の少なくともいずれかの機能を有する薬剤」とは、カビの発生・生育・増殖を抑制する防黴能、微生物を死滅される殺菌能、微生物の発生・生育・増殖を抑制する抗菌能の少なくともいずれかの機能を有する薬剤を意味する。公知の防黴剤、殺菌剤、抗菌剤が使用できる。ただし、前記組成物から形成される偏光子の光学特性を低下させないものであることが好ましい。本発明に使用可能なる防黴、抗菌及び殺菌の少なくともいずれかの機能を有する薬剤としては、例えば、従来の2,4,4’-トリクロロ-2’-ヒドロキシジフェニルなどのフェノール系、二酸化塩素などの塩素系、ヨウ素などのヨウ素系、塩化ベンザルコニウムなどの第4級アンモニウム塩系等が挙げられる。
No. 化合物名
1. 2-クロロメチル-5-クロロ-3-イソチアゾロン
2. 2-シアノメチル-5-クロロ-3-イソチアゾロン
3. 2-ヒドロキシメチル-5-クロロ-3-イソチアゾロン
4. 2-(3-メチルシクロヘキシル)-3-イソチアゾロン
5. 2-(4-クロロフェニル)-4,5-ジクロロ-3-イソチアゾロン
6. 2-(4-エチルフェニル)-3-イソチアゾロン
7. 2-(4-ニトロフェニル)-5-クロロ-3-イソチアゾロン
8. 2-クロロメチル-3-イソチアゾロン
9. 2-メトキシフェニル-4-メチル-5-クロロ-3-イソチアゾロン
10. 2-モルフォリノメチル-5-クロロ-3-イソチアゾロン
これらの化合物は、例えば特開平2-278号公報等を参考に合成することが可能であるが、商品名:トリバクトラン(ヘキスト社製)等の市販品を利用することも可能である。
上記の防黴、抗菌及び殺菌の少なくともいずれかの機能を有する薬剤の、前記組成物中の含有量は特に限定されないが、通常0.01質量%以上、好ましくは0.001質量%以上であり、一方、通常0.5質量%以下、好ましくは0.3質量%以下である。防黴、抗菌及び殺菌の少なくともいずれかの機能を有する薬剤の含有量が前記範囲であると、薬剤の析出や、成膜の際の相分離等を生じさせることなく、充分な防黴、抗菌又は殺菌効果が得られる。
本発明の方法によって得られる偏光子が高い偏光度を有するために、前記組成物は、電子不足である(Electron-Deficient)盤状化合物及び電子リッチである(Electron-Rich)化合物を含有するのが好ましい。電子不足である(Electron-Deficient)盤状化合物及び電子リッチである(Electron-Rich)化合物としては、例えば、特開2006-323377に記載のものを用いることができる。
また、前記組成物中の電子リッチである(Electron-Rich)化合物の割合は、組成物全体を100質量部とした場合に、通常50質量部以下、好ましくは40質量部以下の範囲である。前記化合物の割合がこの範囲であると、組成物の溶液としての粘度を過剰に増大させることなく、添加効果を得られる。
前記二色性色素組成物は、塗布液として調製するのが好ましい。該塗布液の調製に用いる溶剤は、有機溶媒が好ましい。使用可能な有機溶媒の例には、アミド(例、N,N-ジメチルホルムアミド)、スルホキシド(例、ジメチルスルホキシド)、ヘテロ環化合物(例、ピリジン)、炭化水素(例、ベンゼン、トルエン、ヘキサン)、アルキルハライド(例、クロロホルム、ジクロロメタン)、エステル(例、酢酸メチル、酢酸ブチル)、ケトン(例、アセトン、メチルエチルケトン)、エーテル(例、テトラヒドロフラン、1,2-ジメトキシエタン)が含まれる。炭化水素、アルキルハライド及びケトンが好ましい。2種類以上の有機溶媒を併用してもよい。
本発明においては、上記した二色性色素組成物からなる塗布液を配向膜表面へ塗布して湿式な状態にある光吸収異方性膜を形成した後、当該異方性膜を乾燥処理することにより有機溶媒を蒸発させ最終的な本発明の新規な光吸収異方性膜を形成することができる。これにより、特定のシャープな回折ピークにより特徴付けられる高い二色比を持つ光吸収異方性膜を構成することができる。
(1)配向処理工程
(基板を直接、又は該基板上に形成された配向膜をラビング、もしくは光照射する工程)
後記する基板を直接、又は該基板上に形成された配向膜に対しラビング、もしくは異方性の光の照射を行う。ラビングとは、後記詳述するように、前記基板等の表面を、綿布、脱脂綿等のバフにより一定方向に擦って、その方向に平行な微細な溝を形成する配向処理を行う操作であり、ここに二色性色素を塗布することにより、最終的にその表面に配向状態で当該色素を吸着させる操作である。異方性の光とは直線偏光、楕円偏光等の偏光、及び塗膜面に対して斜めの方向から照射される非偏光を言い、これを後記詳述する光活性化合物を含む配向膜に照射することで、一定方向に液晶配向能を生じさ、ここに二色性色素を塗布することにより、最終的にその表面に配向状態で当該色素を吸着させることができる。
本発明に使用する基板は透明であっても、着色等により不透明化した支持体であってもよく、偏光子の用途に応じて選択することができる。例えば、液晶表示素子、OLED素子等に用いられる無アルカリガラス、ソーダガラス、パイレックス(登録商標)ガラス、石英ガラス;固体撮像素子等に用いられる光電変換素子基板;シリコン基板;プラスチック基板;並びに、これらに透明導電膜、カラーフィルタ膜、電極、TFT等の機能層を形成した基板が挙げられる。これらの基板上には、各画素を隔離するブラックマトリクスが形成されていたり、密着促進等のために透明樹脂層を設けたりしていてもよい。
配向膜用組成物の塗布性や接着性向上のために、これらの基板に対して表面処理を行ってもよい。表面処理として、オゾン処理、プラズマ処理などが挙げられる。また、光の透過率や反射率を調節するために、基板表面に有機薄膜、無機酸化物薄膜や金属薄膜等を蒸着など方法によって設けても良い。
プラスチック基板には、その表面にガスバリヤー層及び/又は耐溶剤性層を有していることも好ましい。
本発明に使用する基板は透明な支持体(透明支持体)であるのが好ましく、光透過率が80%以上であるのが好ましい。ガラスまたは、光学的等方性のポリマーフィルムを用いるのが好ましい。ポリマーの具体例および好ましい態様は、特開2002-22942号公報の段落番号[0013]の記載を適用できる。また、従来知られているポリカーボネートやポリスルホンのような複屈折の発現しやすいポリマーであっても国際公開WO00/26705号公報に記載の分子を修飾することで該発現性を低下させたものを用いることもできる。
上記支持体上に形成する配向膜は、当該配向膜上に設けられる光吸収異方性膜の二色性色素に所望の配向を付与できるのであれば、どのような層でもよいが、有機化合物(好ましくはポリマー)のラビング処理、無機化合物の斜方蒸着、マイクログルーブを有する層の形成、あるいはラングミュア・ブロジェット法(LB膜)による有機化合物(例、ω-トリコサン酸、ジオクタデシルメチルアンモニウムクロライド、ステアリル酸メチル)の累積のような手段で、設けることができる。さらに、電場の付与、磁場の付与あるいは異方的な光照射により、配向機能が生じる配向膜も知られている。
本発明においては、ポリマーのラビング処理により形成する配向膜および異方性の光照射により形成する配向膜が特に好ましい。
配向膜の厚さは、0.01~10μmであることが好ましく、0.05~1μmであることがさらに好ましい。
[ラビング配向膜]
ラビング処理は、一般にはポリマー層の表面を、紙や布で一定方向に数回擦ることにより実施することができるが、特に本発明では「液晶便覧」(丸善社発行)に記載されている方法により行うことが好ましい。
配向膜のラビング密度を変える方法としては、「液晶便覧」(丸善社発行)に記載されている方法を用いることができる。ラビング密度(L)は、下記式(A)で定量化されている。
ラビング密度を高くするためには、ラビング回数を増やす、ラビングローラーの接触長を長く、ローラーの半径を大きく、ローラーの回転数を大きく、ステージ移動速度を遅くすればよく、一方、ラビング密度を低くするためには、この逆にすればよい。
ラビング密度と配向膜のプレチルト角との間には、ラビング密度を高くするとプレチルト角は小さくなり、ラビング密度を低くするとプレチルト角は大きくなる関係がある。
本発明に用いる光配向膜を形成するための光配向膜用組成物は、光照射により液晶配向能を生じる組成物であって、光活性化合物を含有する。以下、光配向膜用組成物の調製に用いる種々の成分について説明する。
本明細書において、「光活性化合物」とは、異方性の光を照射することによって異方的に光架橋、光異性化、又は光分解などの光反応を起こす光活性基を有する化合物をいう。
光活性化合物の具体的な例は、多数の文献等に記載がある。例えば、特開2006-285197号公報、特開2007-138138号公報、特開2007-94071号公報、特開2007-121721号公報、特開2007-140465号公報、特開2007-156439号公報、特開2007-133184号公報、特開2009-109831号公報、特許第3883848号、特許第4151746号に記載のアゾ化合物、特開2002-229039号公報に記載の芳香族エステル化合物、特開2002-265541号公報、特開2002-317013号公報に記載の光配向性単位を有するマレイミド及び/又はアルケニル置換ナジイミド化合物、特許第4205195号、特許第4205198号に記載の光架橋性シラン誘導体、特表2003-520878号公報、特表2004-529220号公報、特許第4162850号に記載の光架橋性ポリイミド、ポリアミド、又はエステルが挙げられる。アゾ化合物、光架橋性ポリイミド、ポリアミド、又はエステルが好ましく、アゾ化合物が特に好ましい。
前記組成物は、全固形分の濃度が、0.2質量%以上の塗布液として調製されるのが好ましく、0.5~10質量%程度とするのがより好ましい。
塗布液として調製した前記光配向膜形成用組成物を、表面に塗布して塗膜を形成する。塗布法としては、スピンコーティング法、グラビア印刷法、フレキソ印刷法、インクジェット法、ダイコーティング法、キャップコーティング法、ディッピング等、公知慣用の方法を行うことができる。通常は、有機溶剤で希釈した溶液を塗布するので、塗布後は乾燥させ、光配向膜用塗膜を得る。
一方、光異性化工程において、膜面に対して斜め方向から非偏光を照射する態様では、非偏光の入射角は基板法線に対して10°~80°の範囲が好ましく、照射面における照射エネルギーの均一性、得られるプレチルト角、配向効率等を考慮すると、20°~60°の範囲が更に好ましく、45°が最も好ましい。
なお、非偏光を斜め方向から照射する態様では、光照射装置に偏光フィルタ等を必要とせず、大きな照射強度が得られ、光配向のための照射時間を短縮することができるという利点がある。
照射光の光源としては、キセノンランプ、高圧水銀ランプ、超高圧水銀ランプ、メタルハライドランプ、KrF、ArF等の紫外光レーザー等が挙げられる。光活性基がアゾベンゼン構造である場合は、365nmの紫外線の発光強度が特に大きい超高圧水銀ランプを有効に使用することができる。
冷却条件としては、冷却温度が20℃で1分以上であるが、冷却温度が20℃よりも低い場合は、その限りではない。冷却温度としては、使用する溶剤の融点以上であればよいが、通常-40℃~20℃の範囲が好ましい。液晶配向機能が向上した、より安定な光配向膜を得るには10℃以下が好ましく、冷却時間としては5分以上が好ましい。さらに冷却時間を短縮させるには冷却温度は5℃以下が好ましい。
また、結露防止のため、冷却をする際に乾燥空気や窒素、アルゴン雰囲気下で行ってもよいし、乾燥空気や窒素等を基板に吹きかけながら冷却してもよい。
このようにして、光配向膜を形成することができる。
(配向処理した基板または配向膜上に、有機溶媒に溶解した二色性色素組成物の塗布液を塗布する工程)
上記配向処理した基板または配向膜上に、有機溶媒に溶解した二色性色素組成物(すなわち、二色性色素の有機溶媒溶液)の塗布液を塗布する工程である。
本発明の光吸収異方性膜は、例えば、本発明の二色性色素組成物の塗布液を用いて形成することができる。塗布液の調製に使用する溶媒としては、有機溶媒が好ましい。有機溶媒の例には、アミド(例、N,N-ジメチルホルムアミド)、スルホキシド(例、ジメチルスルホキシド)、ヘテロ環化合物(例、ピリジン)、炭化水素(例、ベンゼン、ヘキサン)、アルキルハライド(例、クロロホルム、ジクロロメタン)、エステル(例、酢酸メチル、酢酸ブチル)、ケトン(例、アセトン、メチルエチルケトン)、エーテル(例、テトラヒドロフラン、1,2-ジメトキシエタン)が含まれる。アルキルハライドおよびケトンが好ましい。2種類以上の有機溶媒を併用してもよい。
二色性色素組成物塗布液の配向膜表面への塗布は、通常の方法(例えば、スピンコーティング法、ワイヤバーコーティング法、押し出しコーティング法、ダイレクトグラビアコーティング法、リバースグラビアコーティング法、ダイコーティング法、インクジェット法、スリットコーティング法、キャップコーティング法、ディッピング等)により実施できる。また、二色性色素組成物塗布液における全固形分の含有量は0.1~20質量%が好ましく、0.1~10質量%がより好ましく、0.5~5質量%がさらに好ましい。
具体的に、湿式成膜法としては、原崎勇次著「コーティング工学」株式会社朝倉書店、1971年3月20日発行、253頁から277頁や市村國宏監修「分子協調材料の創製と応用」株式会社シーエムシー出版、1998年3月3日発行、118頁から149頁などに記載の公知の方法や、例えば、あらかじめ配向処理を施した基材上に、スピンコート法、スプレーコート法、バーコート法、ロールコート法、ブレードコート法、フリースパンコート法、ダイコート法、インクジェット法などで塗布することが挙げられる。
また本発明においては、一方向に配向処理された基材上に、前記基材上の配向処理方向に対して平行でない角度で本発明の二色性色素組成物を塗布して、光吸収性異方性膜を形成することができる。さらに、基材の縦または横方向と略一致する方向に本発明の二色性色素組成物を塗布することがより好ましい。これにより、光学的な欠陥がなく高い二色比を持つ光吸収異方性膜を提供することもできる。また、二色性色素組成物の塗布後、必要な偏光角度を持たせるために基材を切り出す必要がなく、生産性が高い。
前記の、本発明の二色性色素組成物の好ましい塗布方法については、例えば、特開2007-127897等に記載されている。
(前記有機溶媒を蒸発させることにより前記二色性色素組成物を配向させる工程)
塗布に引き続いて行われる、前記有機溶媒溶液の塗膜から、当該有機溶を蒸発させることにより前記二色性色素組成物を配向させる工程である。この場合、乾燥温度としては、好ましくは室温において自然乾燥することであり、塗布により形成された当該色素の配向状態を乱さない(熱緩和等を避ける)ようにするが好ましい。なお、さらに好ましくは減圧処理において、溶媒を蒸発させ、より低温で乾燥することも好ましい。
塗布後、光吸収異方性膜の減圧処理を始めるまでの時間は、短ければ短いほどよく、好ましくは1秒以上30秒以内である。
減圧処理の方法としては、例えば以下の様な方法が挙げられる。塗布液を基材上に塗布し得られた光吸収異方性膜を、減圧処理装置に入れて減圧処理する。例えば特開2006-201759の図9や図10のような減圧処理装置を使用することができる。減圧処理装置の詳細については、特開2004-169975号公報に記載されている。
また、減圧処理時間は、好ましくは5秒以上180秒以内である。上限を上回ると配向緩和前に急速に色素膜を乾燥できず配向が乱れる恐れがあり、下限を下回ると乾燥できず配向が乱れる恐れがある。
本発明でいう光吸収異方性膜とは、色素膜の厚み方向および任意の直交する面内2方向の立体座標系における合計3方向から選ばれる任意の2方向における電磁気学的性質に異方性を有する色素膜である。電磁気学的性質としては、吸収、屈折などの光学的性質、抵抗、容量などの電気的性質などが挙げられる。吸収、屈折などの光学的異方性を有する膜としては、例えば、直線偏光膜、円偏光膜、位相差膜、抵抗率異方性膜などがある。すなわち、本発明の光吸収異方性膜は、偏光膜、位相差膜あるいは抵抗率異方性膜に使用できる。特に、本発明の光吸収異方性膜は、可視光領域全体にわたって高い吸光度を示すため、偏光膜に有用である。
ここで半値幅とは、X線回折測定の一つの回折ピーク内において、ベースラインを基準としたピーク頂点の強度を求め、ピーク頂点の左右に一つずつある、該強度の半分の強度を示す2点をとり、2点のそれぞれが示す周期の値の差をとった値のことである。
一般に、光吸収異方性膜を形成する二色性色素はアスペクト比(=分子長軸長/分子短軸長)の大きな棒状分子であり、分子長軸方向とほぼ一致する方向に、可視光を吸収する遷移モーメントが存在する。そのため、二色性色素の分子長軸と配向軸のなす角度が平均して小さく、ばらつきが小さいほど、光吸収異方性膜は高い二色比を示す。
ここで配向軸とは、光吸収異方性膜が直線偏光に対してもっとも大きな吸光度を示す方向を意味し、通常、配向処理を行なった方向と一致する。
配向処理の具体例としては、すでに詳述したように、二色性色素で染色した樹脂フィルムの延伸、配向膜のラビング、直線偏光の照射、電場・磁場の印加といった方法が挙げられるが、本発明はこれらの方法に限定されるものではないことはすでに述べたとおりである。
二色性色素の分子長軸と配向軸のなす角度のばらつきが大きいと、分子間距離のばらつきも大きくなる。すると、周期構造がある場合、その周期の値もばらつき、X線回折測定で得られる回折ピークはブロードになって大きな半値幅を示すことになる。
これに対し、本発明の光吸収異方性膜で特徴付けられるように、回折ピークの半値幅が一定値以下であるシャープなピークであるということは分子間距離のばらつきが小さく、二色性色素の分子長軸と配向軸のなす角度が平均して小さいこと、すなわち高秩序に配向していることを意味し、高い二色比を発現すると推測される。
これに対し、本発明者らは、本発明の新規な二色性色素含有組成物からなる光吸収異方性膜においては、回折ピークの半値幅が1.0Å以下である光吸収異方性膜が高い二色比を示す新規なものであることを見出した。
本発明の光吸収異方性膜が示す回折ピークの半値幅は、このように少なくとも1.0Å以下、好ましくは0.90Å以下、より好ましくは0.70Å以下、さらに好ましくは0.50Å以下であり、好ましくは0.1Å以上である。半値幅が上限を上回ると、色素の分子間距離のばらつきが大きくなり、高秩序な配向が阻害され好ましくない。またこれが下限を下回ると、配向ひずみを生じやすくなってドメインと粒界を生じ、ヘイズの発生やドメインごとの配向乱れを招く恐れがあり好ましくない。
光吸収異方性膜の回折ピークの周期および半値幅は、薄膜評価用X線回折装置(リガク社製、商品名:「ATX-G」インプレーン光学系)或いはこれと同等の装置で測定されるX線プロファイルから得られる
本発明の光吸収異方性膜では、これらは例えば次の手順により求められる。
この場合、形成された異方性色素膜そのものを偏光素子としてもよく、さらに保護層、粘着層、反射防止層を形成してもよい。
また、上記異方性色素膜を使用して液晶素子を形成するには、上記した(1)~(3)の工程において、支持体(基板)にITO等の透明電極を形成しておき、当該電極上に異方性色素膜(偏光膜)を形成すればよい。なお、この場合、色素膜と接触する透明電極上にポリイミドやポリビニルアルコール等を塗布後、ラビング処理して平行配向した後、上記塗布等の工程を行えばよい。
また、本発明の二色性色素組成物からなる塗布液を配向膜上に適用すると、二色性色素は配向膜との界面では配向膜のチルト角で配向し、空気との界面では空気界面のチルト角で配向する。本発明の二色性色素組成物塗布液を配向膜の表面に塗布後、二色性色素を均一配向(モノドメイン配向)させることで、水平配向を実現することができる。
二色性色素を水平配向させ、且つその配向状態に固定することによって形成された光吸収異方性膜は、偏光素子として利用することができる。
本発明において、チルト角とは、二色性色素の分子の長軸方向と界面(配向膜界面あるいは空気界面)のなす角度を指す。配向膜側のチルト角を有る程度小さくし水平配向させることにより偏光素子として好ましい光学性能がより効果的に得られる。したがって、偏光性能の観点から、好ましい配向膜側のチルト角は0°~10°、さらに好ましくは0°~5°、特に好ましいのは0°~2°、最も好ましくは0°~1°である。また、好ましい空気界面側のチルト角は0°~10°、さらに好ましくは0~5°、特に好ましいのは0~2°である。
また、配向膜側の二色性色素のチルト角は、前記した方法(配向膜チルト角制御剤等)により制御することができる。
かくして形成された本発明の光吸収異方性膜は、光吸収の異方性を利用し直線偏光、円偏光、楕円偏光等を得る偏光膜として機能する他、膜形成プロセスと基材や色素を含有する組成物の選択により、屈折異方性や伝導異方性などの各種異方性膜として機能化が可能となり、様々な種類の、多様な用途に使用可能な偏光素子とすることができる。
これら光学機能を有する層は、例えば以下の様な方法により形成することが出来る。
拡散フィルムとしての機能を有する層は、上記の保護層に微粒子を含む樹脂溶液をコーティングすることにより、形成することができる。
また、位相差フィルムや光学補償フィルムとしての機能を有する層は、ディスコティック液晶性化合物などの液晶性化合物をコーティングして配向させることにより形成することができる。
本発明の液晶表示装置は、前記の二色性色素組成物を用いて製造された光吸収異方性膜、偏光素子などを有し、その液晶性を利用しているものであれば特に限定されないが、具体的には例えばテレビ用ディスプレイ、PC用ディスプレイ、車載用ディスプレイ、屋外用ディスプレイなどが挙げられる。
なお、以下の実施例中、光吸収異方性膜の光学特性に関する測定は下記の通り実施した。
二色比は、ヨウ素系偏光素子を入射光学系に配した分光光度計で光吸収異方性膜の吸光度を測定した後、次式により計算した。
二色比(D)=Az/Ay
Az:光吸収異方性膜の吸収軸方向の偏光に対する吸光度
Ay:光吸収異方性膜の偏光軸方向の偏光に対する吸光度
回折角と距離との関係は、
d=λ/(2*sinθ)、 (d;距離、λ;入射X線波長(CuKα;1.54Å)
により換算した。
クロロホルム98質量部に例示色素(A-46)2質量部を撹拌溶解させて光吸収異方性膜用色素溶液(塗布液)を得た。当該色素溶液を、ラビングによりホモジニアス配向処理を施したポリビニルアルコール配向膜(日産化学工業社製、商品名:PVA-103)付ガラス基板上にスピンコートにより塗布し、自然乾燥させた後、70℃で1分間加熱して光吸収異方性膜を得た。
当該膜の厚みは、0.2μmであった。
クロロホルム98質量部に例示色素(A-58)2質量部を撹拌溶解させて光吸収異方性膜用色素溶液を得た。当該色素溶液(塗布液)を、ラビングによりホモジニアス配向処理を施したポリビニルアルコール配向膜(日産化学工業社製、商品名:PVA-103)付ガラス基板上にスピンコートにより塗布し、自然乾燥させた後、40℃で1時間加熱して光吸収異方性膜を得た。当該膜の厚みは、0.2μmであった。
得られた光吸収異方性膜の二色比は18であった。当該膜の配向軸垂直方向および配向軸方向から得られたX線回折パターンを図2に示す。配向軸垂直方向に4つ、配向軸方向に1つのピークが検出された。各ピークから求められた周期と半値幅を表2に示す。
クロロホルム98質量部に例示色素(C-10)2質量部を撹拌溶解させて光吸収異方性膜用色素溶液を得た。当該色素溶液(塗布液)を、ラビングによりホモジニアス配向処理を施したポリビニルアルコール配向膜(日産化学工業社製、商品名:PVA-103)付ガラス基板上にスピンコートにより塗布し、自然乾燥させた後、40℃で1時間加熱して光吸収異方性膜を得た。当該膜の厚みは、0.2μmであった。
得られた光吸収異方性膜の二色比は18であった。当該膜の配向軸垂直方向および配向軸方向から得られたX線回折パターンを図3に示す。配向軸垂直方向に2つのピークが検出された。各ピークから求められた周期と半値幅を表3に示す。
クロロホルム98質量部に例示色素(D-2)2質量部を撹拌溶解させて光吸収異方性膜用色素溶液を得た。当該色素溶液(塗布液)を、ラビングによりホモジニアス配向処理を施したポリビニルアルコール配向膜(日産化学工業社製、商品名:PVA-103)付ガラス基板上にスピンコートにより塗布し、自然乾燥させた後、40℃で1時間加熱して光吸収異方性膜を得た。当該膜の厚みは、0.2μmであった。
得られた光吸収異方性膜の二色比は19であった。当該膜の配向軸垂直方向および配向軸方向から得られたX線回折パターンを図4に示す。配向軸垂直方向に2つのピークが検出された。各ピークから求められた周期と半値幅を表4に示す。
得られた光吸収異方性膜の二色比は6であった。当該膜の配向軸垂直方向から得られたX線回折パターンを図5に示す。配向軸垂直方向に1つのピークが検出された。ピークから求められた周期と半値幅を表5に示す。
Claims (11)
- X線回折測定において膜面内方向の周期構造に由来する回折ピークを示し、その半値幅が1.0Å以下であることを特徴とする二色性色素の少なくとも一種を有する光吸収異方性膜。
- 前記回折ピークが配向軸垂直方向の周期構造に由来する、請求項1に記載の光吸収異方性膜。
- 前記回折ピークが表す周期が3.5~10.0Åである、請求項1または2に記載の光吸収異方性膜。
- 膜厚が0.01~30μmである、請求項1~3のいずれかに記載の光吸収異方性膜。
- 配向膜上に形成されたことを特徴とする、請求項1~4のいずれかに記載の光吸収異方性膜。
- 前記二色性色素として、下記一般式(I)で表されるアゾ色素を含有し、かつ、液晶性を有する、請求項1~5のいずれかに記載の光吸収異方性膜を形成するための二色性色素組成物。
- 前記一般式(I)で表されるアゾ色素が、下記一般式(Ia)で表される化合物であることを特徴とする請求項6に記載の二色性色素組成物。
- 前記一般式(I)で表されるネマチック液晶性を有するアゾ色素が、下記一般式(Ib)又は(Ic)で表されるアゾ色素であることを特徴とする請求項6または請求項7に記載の二色性色素組成物。
- 請求項1~請求項5のいずれかに記載の光吸収異方性膜を用いた偏光素子。
- 請求項9に記載の偏光素子を用いた表示装置。
- 少なくとも
[1]基板を直接、又は該基板上に形成された配向膜をラビング、もしくは光照射する工程と、
[2]該基板又は該配向膜上に、請求項6~8のいずれかに記載の二色性色素組成物を塗布する工程と、
[3]該二色性色素組成物を配向させ偏光素子とする工程
をこの順に含む請求項9に記載の偏光素子の製造方法。
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- 2009-09-30 WO PCT/JP2009/067108 patent/WO2010038817A1/ja active Application Filing
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JP2013101328A (ja) * | 2011-10-12 | 2013-05-23 | Sumitomo Chemical Co Ltd | 偏光膜、円偏光板及びそれらの製造方法 |
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JPWO2017154695A1 (ja) * | 2016-03-08 | 2019-02-07 | 富士フイルム株式会社 | 着色組成物、光吸収異方性膜、積層体および画像表示装置 |
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JP2022176266A (ja) * | 2018-06-27 | 2022-11-25 | 富士フイルム株式会社 | 偏光子および画像表示装置 |
US11768323B2 (en) | 2018-06-27 | 2023-09-26 | Fujifilm Corporation | Polarizer and image display device |
JP7366896B2 (ja) | 2018-06-27 | 2023-10-23 | 富士フイルム株式会社 | 偏光子および画像表示装置 |
JP7402951B2 (ja) | 2018-06-27 | 2023-12-21 | 富士フイルム株式会社 | 偏光子および画像表示装置 |
JPWO2020004106A1 (ja) * | 2018-06-27 | 2021-08-02 | 富士フイルム株式会社 | 偏光子および画像表示装置 |
WO2020004106A1 (ja) * | 2018-06-27 | 2020-01-02 | 富士フイルム株式会社 | 偏光子および画像表示装置 |
Also Published As
Publication number | Publication date |
---|---|
KR20160042459A (ko) | 2016-04-19 |
US8927070B2 (en) | 2015-01-06 |
KR101608680B1 (ko) | 2016-04-04 |
CN102171592A (zh) | 2011-08-31 |
JP5412225B2 (ja) | 2014-02-12 |
CN102171592B (zh) | 2014-05-28 |
US20110177315A1 (en) | 2011-07-21 |
KR20110063854A (ko) | 2011-06-14 |
JP2010107975A (ja) | 2010-05-13 |
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