WO2022030266A1 - Procédé de fabrication de couche optiquement anisotrope - Google Patents

Procédé de fabrication de couche optiquement anisotrope Download PDF

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WO2022030266A1
WO2022030266A1 PCT/JP2021/027346 JP2021027346W WO2022030266A1 WO 2022030266 A1 WO2022030266 A1 WO 2022030266A1 JP 2021027346 W JP2021027346 W JP 2021027346W WO 2022030266 A1 WO2022030266 A1 WO 2022030266A1
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liquid crystal
crystal compound
optically anisotropic
anisotropic layer
composition layer
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PCT/JP2021/027346
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English (en)
Japanese (ja)
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勇太 高橋
慎平 吉田
啓祐 小玉
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富士フイルム株式会社
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Priority to CN202180057967.1A priority Critical patent/CN116113858A/zh
Priority to KR1020237003823A priority patent/KR20230031360A/ko
Priority to JP2022541436A priority patent/JP7480306B2/ja
Publication of WO2022030266A1 publication Critical patent/WO2022030266A1/fr

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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
    • H10K59/80—Constructional details
    • H10K59/8793—Arrangements for polarized light emission
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • G02B5/3083—Birefringent or phase retarding elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
    • B29D7/00—Producing flat articles, e.g. films or sheets
    • B29D7/01—Films or sheets
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K19/00—Liquid crystal materials
    • C09K19/52—Liquid crystal materials characterised by components which are not liquid crystals, e.g. additives with special physical aspect: solvents, solid particles
    • C09K19/58—Dopants or charge transfer agents
    • C09K19/586—Optically active dopants; chiral dopants
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • 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
    • 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
    • G02F1/133528—Polarisers
    • 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
    • G02F1/13363—Birefringent elements, e.g. for optical compensation
    • 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
    • G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00—Electroluminescent light sources
    • H05B33/02—Details

Definitions

  • the present invention relates to a method for manufacturing an optically anisotropic layer.
  • the retardation layer having refractive index anisotropy (optical anisotropy layer) is applied to various applications such as an antireflection film of a display device and an optical compensation film of a liquid crystal display device.
  • optically anisotropic layer as described in Patent Document 1, a laminated optical anisotropic layer composed of a plurality of layers is disclosed.
  • the present invention provides a simple method for producing an optically anisotropic layer having a plurality of regions in which the orientation state of the liquid crystal compound is fixed and the orientation state of the liquid crystal compound is different along the thickness direction. That is the issue.
  • Step 1 of forming a composition layer containing a liquid crystal compound having a polymerizable group and Step 2 in which the composition layer is heat-treated to orient the liquid crystal compound in the composition layer, and After the step 2, the composition layer is irradiated with light for 50 seconds or less and at 300 mJ / cm 2 or less under the condition of an oxygen concentration of 1% by volume or more.
  • step 3 the composition layer is heat-treated at a temperature higher than that at the time of light irradiation, and step 4 After the step 4, the composition layer is subjected to a curing treatment to form an optically anisotropic layer having a plurality of regions having different orientation states of the liquid crystal compounds along the thickness direction. Manufacturing method of anisotropic layer.
  • the composition layer contains a photosensitive material selected from the group consisting of a photopolymerization initiator and a photosensitizer.
  • the method for producing an optically anisotropic layer according to (1) wherein the molar extinction coefficient of the photosensitive material at the wavelength of light irradiation in step 3 is 5000 L / (mol ⁇ cm) or less.
  • the composition layer contains a chiral agent and contains The method for producing an optically anisotropic layer according to (1) or (2), wherein the chiral agent contains a photosensitive chiral agent whose spiral-inducing force is changed by light irradiation.
  • the present invention it is possible to provide a simple method for producing an optically anisotropic layer having a plurality of regions in which the orientation state of the liquid crystal compound is fixed and the orientation state of the liquid crystal compound is different along the thickness direction.
  • composition layer for demonstrating an example of the step 1A of the 1st Embodiment of the manufacturing method of the optically anisotropic layer of this invention. It is sectional drawing of the composition layer for demonstrating an example of the step 3A of the 1st Embodiment of the manufacturing method of the optically anisotropic layer of this invention. It is sectional drawing of the composition layer for demonstrating an example of the case where the step 4A of the 1st Embodiment of the manufacturing method of the optically anisotropic layer of this invention is carried out.
  • the slow axis is defined at 550 nm unless otherwise specified.
  • Re ( ⁇ ) and Rth ( ⁇ ) represent in-plane retardation at wavelength ⁇ and retardation in the thickness direction, respectively. Unless otherwise specified, the wavelength ⁇ is 550 nm.
  • the values of the average refractive index of the main optical films are exemplified below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethylmethacrylate (1.49), And polystyrene (1.59).
  • light means active light or radiation, for example, the emission line spectrum of a mercury lamp, far ultraviolet rays typified by an excima laser, extreme ultraviolet rays (EUV light: Extreme Ultraviolet), X-rays, ultraviolet rays, and the like. And electron beam (EB: Electron Beam) and the like. Of these, ultraviolet rays are preferable.
  • visible light refers to light having a diameter of 380 to 780 nm. Further, in the present specification, unless otherwise specified, the measurement wavelength is 550 nm.
  • the twist angle is preferably more than 0 ° and less than 360 °.
  • the cholesteric liquid crystal phase which will be described later, is a phase in which the liquid crystal compound has a periodic structure in which the liquid crystal compound is spirally oriented, and the twist angle is 360 ° or more.
  • a feature of the method for producing an optically anisotropic layer of the present invention is that a predetermined step is carried out.
  • the liquid crystal compound in the composition layer is oriented.
  • the oxygen concentration is low in a part of the region of the composition layer formed on the substrate side, and the oxygen concentration is high in the other region on the surface side opposite to the substrate side. Therefore, when such a composition layer is irradiated with light under predetermined conditions, the polymerization of the liquid crystal compound does not easily proceed in the region where the oxygen concentration is high, whereas in the region where the oxygen concentration is low, it is difficult to proceed. , Polymerization of the liquid crystal compound is easy to proceed.
  • the orientation state of the liquid crystal compound is fixed. Then, during the heat treatment carried out after light irradiation, the orientation state of the liquid crystal compound does not change in the region where the polymerization of the liquid crystal compound has progressed, but the orientation state of the liquid crystal compound has not changed in the region where the polymerization of the liquid crystal compound has been difficult to proceed. Is changed, and the changed orientation state during the curing process is fixed. As a result, an optically anisotropic layer having a plurality of regions having different orientation states of the fixed liquid crystal compounds along the thickness direction is produced.
  • the method for producing an optically anisotropic layer of the present invention is Step 1 of forming a composition layer containing a liquid crystal compound having a polymerizable group, and Step 2 in which the composition layer is heat-treated to orient the liquid crystal compound in the composition layer, and After the step 2, the composition layer is irradiated with light for 50 seconds or less and at 300 mJ / cm 2 or less under the condition of an oxygen concentration of 1% by volume or more.
  • the composition layer is heat-treated at a temperature higher than that at the time of light irradiation, and step 4
  • the composition layer is subjected to a curing treatment to form an optically anisotropic layer having a plurality of regions having different orientation states of the liquid crystal compounds along the thickness direction.
  • the orientation state of the liquid crystal compound is fixed.
  • regions in which the orientation states of the liquid crystal compounds are different for example, an embodiment in which the spiral pitches of the cholesteric liquid crystal phases in a plurality of regions are different from each other, and the liquid crystal compound with respect to the layer surface of the plurality of regions.
  • the orientation of the two regions is different, and one of the two regions is a region in which the liquid crystal compound exhibits an isotropic phase, and the other region is the orientation in which the liquid crystal compound is oriented.
  • An embodiment in which the state is fixed is mentioned.
  • each preferred embodiment of the method for producing an optically anisotropic layer of the present invention will be described in detail.
  • the first embodiment of the method for producing an optically anisotropic layer of the present invention comprises the following steps 1A to 5A.
  • an optically anisotropic layer having a region in which the alignment state of the liquid crystal compound twisted and oriented along a spiral axis extending along the thickness direction is fixed is formed.
  • Step 1A Forming a composition layer containing at least a photosensitive chiral agent whose spiral-inducing force changes by light irradiation and a liquid crystal compound having a polymerizable group
  • Step 2A Heat-treating the composition layer.
  • Step 3A to orient the liquid crystal compound in the composition layer After step 2A, the composition layer is irradiated with light for 50 seconds or less under the condition of an oxygen concentration of 1% by volume or more, and Step 4A performed at 300 mJ / cm 2 or less: After step 3A, the composition layer is heat-treated at a temperature higher than that at the time of light irradiation Step 5A: After step 4A, the composition layer is cured. A step of forming an optically anisotropic layer having a plurality of regions having different orientation states of the liquid crystal compound along the thickness direction. As will be described later, in the first embodiment, the optically anisotropic layer having the above characteristics is produced.
  • the total content of the chiral agent (total content of all chiral agents) in the composition layer is preferably 5.0% by mass or less with respect to the total mass of the liquid crystal compound.
  • Step 1A is a step of forming a composition layer containing at least a photosensitive chiral agent whose spiral-inducing force is changed by light irradiation and a liquid crystal compound having a polymerizable group.
  • a composition layer to be subjected to a light irradiation treatment described later is formed.
  • the materials used in this step will be described in detail, and then the procedure of the step will be described in detail.
  • the composition layer of step 1A contains a chiral agent containing at least a photosensitive chiral agent whose spiral-inducing force is changed by light irradiation.
  • a photosensitive chiral agent whose spiral-inducing force changes by light irradiation will be described in detail.
  • the spiral-inducing force (HTP) of the chiral agent is a factor indicating the spiral orientation ability represented by the following formula (A).
  • HTP 1 / (length of spiral pitch (unit: ⁇ m) ⁇ concentration of chiral agent to liquid crystal compound (mass%)) [ ⁇ m -1 ]
  • the photosensitive chiral agent whose spiral-inducing force changes by light irradiation may be liquid crystal or non-liquid crystal.
  • the chiral agent A generally contains an asymmetric carbon atom in many cases.
  • the chiral agent A may be an axial asymmetric compound or a planar asymmetric compound that does not contain an asymmetric carbon atom.
  • the chiral agent A may be a chiral agent whose spiral-inducing force is increased by light irradiation, or may be a chiral agent whose spiral-inducing force is decreased. Of these, a chiral agent whose spiral-inducing force is reduced by light irradiation is preferable.
  • "increase and decrease of spiral-inducing force” means increase / decrease when the initial spiral direction (before light irradiation) of chiral agent A is "positive".
  • Examples of the chiral agent A include so-called photoreactive chiral agents.
  • the photoreactive chiral agent is a compound having a chiral portion and a photoreactive portion whose structure is changed by light irradiation, and for example, a compound that greatly changes the torsional force of the liquid crystal compound according to the irradiation amount.
  • Examples of photochemical compounds whose structure changes due to light irradiation are photochromic compounds (Kingo Uchida, Masahiro Irie, Chemical Industry, vol.64, 640p, 1999, Kingo Uchida, Masahiro Irie, Fine Chemicals, vol.28 (9), 15p. , 1999) and the like.
  • the structural change means decomposition, addition reaction, isomerization, racemization, [2 + 2] photocyclization, dimerization reaction, etc. caused by light irradiation to the photochemical reaction site, and the structural change is irreversible.
  • the chiral site include Hiroyuki Nohira, Review of Chemistry, No. 22. Chemistry of liquid crystal, 73p: Asymmetric carbon described in 1994 and the like correspond to this.
  • Examples of the chiral agent A include photoreactive chiral agents described in paragraphs 0044 to 0047 of JP-A-2001-159709, optically active compounds described in paragraphs 0019 to 0043 of JP-A-2002-179669, and JP-A.
  • optically active compound described The optically active compound described, the optically active compound described in paragraphs 0015 to 0044 of JP-A-2002-302487, the optically active polyester described in paragraphs 0015 to 0050 of JP-A-2002-338668, JP-A-2003-055315.
  • the optically active compounds described in paragraphs 0012 to 0053 of WO2018 / 194157A and the optically active compounds described in paragraphs 0020 to 0049 of JP-A-2002-179682 can be mentioned.
  • the chiral agent A is preferably a compound having at least a photoisomerization site, and more preferably the photoisomerization site has a photoisomerizable double bond.
  • the photoisomerization site having a double bond capable of photoisomerization is a stilbene site, a chalcone site, an azobenzene site or a stilbene site in that photoisomerization is likely to occur and the difference in spiral induced force before and after light irradiation is large.
  • the stilbene moiety is preferred, and the cinnamoyl moiety, chalcone moiety or stilbene moiety is more preferred in that the absorption of visible light is small.
  • the photoisomerization site corresponds to the photoreaction site whose structure is changed by the above-mentioned light irradiation.
  • the chiral agent A has a trans-type photoisomerizable double bond in that the initial spiral-inducing force (before light irradiation) is high and the amount of change in the spiral-inducing force due to light irradiation is more excellent. It is preferable to do. Further, the chiral agent A has a cis-type photoisomerizable double bond in that the initial spiral-inducing force (before light irradiation) is low and the amount of change in the spiral-inducing force due to light irradiation is more excellent. It is preferable to do.
  • the chiral agent A preferably has any one of a binaphthyl partial structure, an isosorbide partial structure (a partial structure derived from isosorbide), and an isomannide partial structure (a partial structure derived from isosorbide). ..
  • the binaphthyl partial structure, the isosorbide partial structure, and the isosorbide partial structure are intended to have the following structures, respectively.
  • the part of the binaphthyl substructure where the solid line and the broken line are parallel represents a single bond or a double bond. In the structure shown below, * represents the bonding position.
  • the chiral agent A may have a polymerizable group.
  • the type of the polymerizable group is not particularly limited, and a functional group capable of an addition polymerization reaction is preferable, a polymerizable ethylenically unsaturated group or a ring-polymerizable group is more preferable, and a (meth) acryloyl group, a vinyl group, a styryl group, etc. Alternatively, an allyl group is more preferred.
  • Equation (C) R-L-R R represents a group each independently having at least one site selected from the group consisting of a cinnamoyl site, a chalcone site, an azobenzene site, and a stilbene site.
  • L is a divalent linking group formed by removing two hydrogen atoms from the structure represented by the formula (D) (a divalent link formed by removing two hydrogen atoms from the above binaphthyl partial structure).
  • a divalent linking group represented by the formula (E) (a divalent linking group composed of the isosorbide partial structure), or a divalent linking group represented by the formula (F) (the isomannide partial structure).
  • Step 1A at least the above-mentioned chiral agent A is used.
  • Step 1A may be an embodiment in which two or more kinds of chiral agents A are used, or a chiral agent whose spiral inducing force does not change by irradiation with at least one kind of chiral agent A and at least one kind of light (hereinafter, simply "chiral agent").
  • B a chiral agent whose spiral inducing force does not change by irradiation with at least one kind of chiral agent A and at least one kind of light
  • B a chiral agent whose spiral inducing force does not change by irradiation with at least one kind of chiral agent A and at least one kind of light (hereinafter, simply "chiral agent"). B ”) may be used.
  • the chiral agent B may be liquid crystal or non-liquid crystal.
  • the chiral agent B generally contains an asymmetric carbon atom in many cases.
  • the chiral agent B may be an axial
  • Examples of the type of the polymerizable group include the polymerizable group that the chiral agent A may have.
  • the chiral agent B a known chiral agent can be used.
  • the chiral agent B is preferably a chiral agent that induces a spiral in the opposite direction to the above-mentioned chiral agent A. That is, for example, when the spiral induced by the chiral agent A is in the right direction, the helix induced by the chiral agent B is in the left direction.
  • the molar extinction coefficient of the chiral agent A and the chiral agent B is not particularly limited, but the molar extinction coefficient at the wavelength of the light irradiated in step 3A described later (for example, 365 nm) is 100 to 100,000 L / (mol ⁇ cm). It is preferably 500 to 50,000 L / (mol ⁇ cm), and more preferably 500 to 50,000 L / (mol ⁇ cm).
  • the contents of the chiral agent A and the chiral agent B in the composition layer can be appropriately set according to the characteristics (for example, retardation and wavelength dispersion) of the optically anisotropic layer to be formed. Since the twist angle of the liquid crystal compound in the optically anisotropic layer largely depends on the types of the chiral auxiliary A and the chiral agent B and their addition concentrations, it is possible to control the orientation state of the liquid crystal compound by adjusting these. can.
  • the total content of the chiral agent (total content of all chiral agents) in the composition layer is not particularly limited, but the total mass of the liquid crystal compound is easy to control in that the orientation state of the liquid crystal compound is easily controlled.
  • the total mass of the liquid crystal compound is easy to control in that the orientation state of the liquid crystal compound is easily controlled.
  • 5.0% by mass or less is preferable, 4.0% by mass or less is more preferable, and 2.0% by mass or less is further preferable.
  • the lower limit is not particularly limited, but is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, still more preferably 0.05% by mass.
  • the content of the chiral agent A in the chiral agent is not particularly limited, but is preferably 5 to 95% by mass, preferably 10 to 90% by mass, based on the total mass of the chiral agent, in that the orientation state of the liquid crystal compound can be easily controlled. Is more preferable.
  • the composition layer of step 1A contains a liquid crystal compound having a polymerizable group.
  • the type of the liquid crystal compound is not particularly limited. Generally, a liquid crystal compound can be classified into a rod-shaped type (rod-shaped liquid crystal compound) and a disk-shaped type (discotic liquid crystal compound) according to its shape. Further, the liquid crystal compound can be classified into a small molecule type and a high molecular type.
  • a polymer generally refers to a molecule having a degree of polymerization of 100 or more (Polymer Physics / Phase Transition Dynamics, Masao Doi, p. 2, Iwanami Shoten, 1992).
  • any liquid crystal compound can be used, but it is preferable to use a rod-shaped liquid crystal compound or a discotic liquid crystal compound, and it is more preferable to use a rod-shaped liquid crystal compound.
  • Two or more kinds of rod-shaped liquid crystal compounds, two or more kinds of discotic liquid crystal compounds, or a mixture of a rod-shaped liquid crystal compound and a discotic liquid crystal compound may be used.
  • the rod-shaped liquid crystal compound for example, those described in claim 1 of JP-A No. 11-513019 and paragraphs 0026 to 0098 of JP-A-2005-289980 can be preferably used.
  • the discotic liquid crystal compound for example, those described in paragraphs 0020 to 0067 of JP-A-2007-108732 and paragraphs 0013 to 0108 of JP-A-2010-244033 can be preferably used.
  • the type of the polymerizable group of the liquid crystal compound is not particularly limited, a functional group capable of an addition polymerization reaction is preferable, a polymerizable ethylenically unsaturated group or a ring-polymerizable group is more preferable, and a (meth) acryloyl group or a vinyl group is preferable. , Styryl group, or allyl group is more preferable.
  • the optically anisotropic layer produced in the present invention is a layer formed by fixing a liquid crystal compound having a polymerizable group (a rod-shaped liquid crystal compound having a polymerizable group or a discotic liquid crystal compound) by polymerization or the like. Yes, it is no longer necessary to show liquid crystallinity after forming a layer.
  • the content of the liquid crystal compound in the composition layer is not particularly limited, but is preferably 60% by mass or more, preferably 70% by mass or more, based on the total mass of the composition layer, from the viewpoint of easy control of the orientation state of the liquid crystal compound. More preferred.
  • the upper limit is not particularly limited, but is preferably 99% by mass or less, and more preferably 97% by mass or less.
  • the composition layer may contain components other than the chiral agent and the liquid crystal compound.
  • the composition layer may contain a polymerization initiator.
  • the polymerization initiator include known polymerization initiators, photopolymerization initiators and thermal polymerization initiators, and photopolymerization initiators are preferable.
  • a polymerization initiator that is sensitive to the light irradiated in step 5A described later is preferable.
  • the polymerization initiator has a molar extinction coefficient that is the largest of the wavelengths of the light irradiated in step 3A, which is 0.1 times or less the molar extinction coefficient of the maximum wavelength of the light that is irradiated in step 5A. Is preferable.
  • the molar extinction coefficient at the wavelength of light irradiation in the step 3A of the polymerization initiator is preferably 5000 L / (mol ⁇ cm) or less, and 4000 L / (mol ⁇ cm) in that a predetermined optically anisotropic layer is easily formed. ) Or less is more preferable, and 3000 L / (mol ⁇ cm) or less is further preferable.
  • the lower limit is not particularly limited, and is preferably 0 L / (mol ⁇ cm), but is often 30 L / (mol ⁇ cm) or more.
  • the content of the polymerization initiator in the composition layer is not particularly limited, but is preferably 0.01 to 20% by mass, more preferably 0.5 to 10% by mass, based on the total mass of the composition layer.
  • the composition layer may contain a photosensitizer.
  • the type of the photosensitizer is not particularly limited, and examples thereof include known photosensitizers.
  • the molar extinction coefficient at the wavelength of light irradiation in step 3A of the photosensitizer is preferably 5000 L / (mol ⁇ cm) or less, 4800 L / (mol ⁇ ⁇ , in that a predetermined optically anisotropic layer is easily formed. cm) or less is more preferable, and 4500 L / (mol ⁇ cm) or less is further preferable.
  • the lower limit is not particularly limited, and is preferably 0 L / (mol ⁇ cm), but is often 30 L / (mol ⁇ cm) or more.
  • the content of the photosensitizer in the composition layer is not particularly limited, but is preferably 0.01 to 20% by mass, more preferably 0.5 to 10% by mass, based on the total mass of the composition layer.
  • the composition layer may contain a polymerizable monomer different from the liquid crystal compound having a polymerizable group.
  • the polymerizable monomer include a radically polymerizable compound and a cationically polymerizable compound, and a polyfunctional radically polymerizable monomer is preferable.
  • the polymerizable monomer include the polymerizable monomers described in paragraphs 0018 to 0020 in JP-A-2002-296423.
  • the content of the polymerizable monomer in the composition layer is not particularly limited, but is preferably 1 to 50% by mass, more preferably 5 to 30% by mass, based on the total mass of the liquid crystal compound.
  • the composition layer may contain a surfactant.
  • the surfactant include conventionally known compounds, but fluorine-based compounds are preferable. Specific examples thereof include the compounds described in paragraphs 0028 to 0056 of JP-A-2001-330725 and the compounds described in paragraphs 0069 to 0126 of Japanese Patent Application Laid-Open No. 2003-295212.
  • the composition layer may contain a polymer.
  • the polymer include cellulose esters.
  • examples of the cellulose ester include those described in paragraph 0178 in JP-A-2000-155216.
  • the content of the polymer in the composition layer is not particularly limited, but is preferably 0.1 to 10% by mass, more preferably 0.1 to 8% by mass, based on the total mass of the liquid crystal compound.
  • composition layer may contain an additive (orientation control agent) that promotes horizontal orientation or vertical orientation in order to bring the liquid crystal compound into a horizontal or vertical orientation state.
  • additive orientation control agent
  • the substrate is a plate that supports the composition layer.
  • a transparent substrate is preferable.
  • the transparent substrate is intended to be a substrate having a visible light transmittance of 60% or more, and the transmittance is preferably 80% or more, more preferably 90% or more.
  • the retardation value (Rth (550)) in the thickness direction at a wavelength of 550 nm of the substrate is not particularly limited, but is preferably ⁇ 110 to 110 nm, and more preferably ⁇ 80 to 80 nm.
  • the in-plane retardation value (Re (550)) at a wavelength of 550 nm of the substrate is not particularly limited, but is preferably 0 to 50 nm, more preferably 0 to 30 nm, still more preferably 0 to 10 nm.
  • the material for forming the substrate a polymer having excellent optical performance transparency, mechanical strength, thermal stability, moisture shielding property, isotropic property and the like is preferable.
  • the polymer film that can be used as a substrate include cellulose acylate films (for example, cellulose triacetate film (refractive index 1.48), cellulose diacetate film, cellulose acetate butyrate film, cellulose acetate propionate film).
  • Polyolefin films such as polyethylene and polypropylene, polyester films such as polyethylene terephthalate and polyethylene naphthalate, polyether sulfone films, polyacrylic films such as polymethylmethacrylate, polyurethane films, polycarbonate films, polysulfone films, polyether films, polymethylpentene films. , Polyether ketone film, (meth) acrylic nitrile film, and polymer film having an alicyclic structure (Norbornen-based resin (Arton: trade name, JSR), amorphous polyolefin (Zeonex: trade name, Nippon Zeon) Company)).
  • the material of the polymer film triacetyl cellulose, polyethylene terephthalate, or a polymer having an alicyclic structure is preferable, and triacetyl cellulose is more preferable.
  • the substrate may contain various additives (for example, an optical anisotropy adjuster, a wavelength dispersion adjuster, fine particles, a plasticizer, an ultraviolet inhibitor, a deterioration inhibitor, a release agent, etc.).
  • additives for example, an optical anisotropy adjuster, a wavelength dispersion adjuster, fine particles, a plasticizer, an ultraviolet inhibitor, a deterioration inhibitor, a release agent, etc.
  • the thickness of the substrate is not particularly limited, but is preferably 10 to 200 ⁇ m, more preferably 10 to 100 ⁇ m, and even more preferably 20 to 90 ⁇ m.
  • the substrate may be made of a plurality of laminated sheets.
  • the substrate may be subjected to surface treatment (eg, glow discharge treatment, corona discharge treatment, ultraviolet (UV) treatment, flame treatment) on the surface of the substrate in order to improve adhesion to a layer provided on the substrate.
  • an adhesive layer undercoat layer
  • the substrate is solidified with inorganic particles having an average particle size of about 10 to 100 nm.
  • a polymer layer mixed by mass ratio of 5 to 40% by mass may be arranged on one side of the substrate.
  • the substrate may be a so-called temporary support. That is, after carrying out the production method of the present invention, the substrate may be peeled off from the optically anisotropic layer.
  • the surface of the substrate may be directly subjected to the rubbing treatment. That is, a substrate that has been subjected to a rubbing treatment may be used.
  • the direction of the rubbing treatment is not particularly limited, and the optimum direction is appropriately selected according to the direction in which the liquid crystal compound is desired to be oriented.
  • a processing method widely adopted as a liquid crystal alignment processing step of an LCD (liquid crystal display) can be applied. That is, a method of obtaining orientation by rubbing the surface of the substrate in a certain direction with paper, gauze, felt, rubber, nylon fiber, polyester fiber, or the like can be used.
  • the alignment film may be arranged on the substrate.
  • the alignment film can be a rubbing treatment of an organic compound (preferably a polymer), an oblique deposition of an inorganic compound, the formation of a layer with microgrooves, or an organic compound (eg, ⁇ -tricosan) by the Langmuir-Blojet method (LB film). It can be formed by means such as accumulation of acid (acid, dioctadecylmethylammonium chloride, methyl stearylate). Further, an alignment film in which an alignment function is generated by applying an electric field, applying a magnetic field, or irradiating with light (preferably polarized light) is also known. The alignment film is preferably formed by a polymer rubbing treatment.
  • Examples of the polymer contained in the alignment film include the methacrylate-based copolymer, the styrene-based copolymer, the polyolefin, the polyvinyl alcohol and the modified polyvinyl alcohol, and poly (N-) described in paragraph 0022 of JP-A-8-338913.
  • Methylolacrylamide methacrylate-based copolymer, the styrene-based copolymer, the polyolefin, the polyvinyl alcohol and the modified polyvinyl alcohol, and poly (N-) described in paragraph 0022 of JP-A-8-338913.
  • Methylolacrylamide methylolacrylamide
  • polyester polyimide
  • vinyl acetate copolymer polymer
  • carboxymethyl cellulose and polycarbonate.
  • a silane coupling agent can also be used as a polymer.
  • water-soluble polymers eg, poly (N-methylolacrylamide), carboxymethyl cellulose, gelatin, polyvinyl alcohol, modified polyvinyl alcohol
  • gelatin, polyvinyl alcohol or modified polyvinyl alcohol are more preferable
  • polyvinyl alcohol or modified polyvinyl alcohol is more preferable. Is even more preferable.
  • the alignment film is subjected to heat-drying (cross-linking) and rubbing treatment after applying a solution containing the polymer as an alignment film-forming material and an arbitrary additive (for example, a cross-linking agent) onto the substrate. It can be formed by.
  • step 1A a composition layer containing the above-mentioned components is formed, but the procedure is not particularly limited.
  • a method of applying a composition containing the above-mentioned chiral agent and a liquid crystal compound having a polymerizable group onto a substrate and subjecting it to a drying treatment as necessary hereinafter, also simply referred to as “coating method”
  • a method of separately forming a composition layer and transferring it onto a substrate can be mentioned.
  • the coating method is preferable from the viewpoint of productivity.
  • the coating method will be described in detail.
  • the composition used in the coating method includes the above-mentioned chiral agent, a liquid crystal compound having a polymerizable group, and other components used as necessary (for example, a polymerization initiator, a polymerizable monomer, a surfactant). , And polymers, etc.).
  • the content of each component in the composition is preferably adjusted to be the content of each component in the composition layer described above.
  • the coating method is not particularly limited, and examples thereof include a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die coating method. If necessary, after the composition is applied, a treatment for drying the coating film applied on the substrate may be carried out. By carrying out the drying treatment, the solvent can be removed from the coating film.
  • the film thickness of the coating film is not particularly limited, but is preferably 0.1 to 20 ⁇ m, more preferably 0.2 to 15 ⁇ m, and even more preferably 0.5 to 10 ⁇ m.
  • Step 2A is a step of subjecting the composition layer to heat treatment to orient the liquid crystal compound in the composition layer.
  • the liquid crystal compound in the composition layer is in a predetermined orientation state.
  • the heat treatment conditions the optimum conditions are selected according to the liquid crystal compound used. Among them, the heating temperature is often 25 to 250 ° C, more often 40 to 150 ° C, and even more often 50 to 130 ° C.
  • the heating time is often 0.1 to 60 minutes, and more often 0.2 to 5 minutes.
  • the orientation state of the liquid crystal compound obtained in step 2A changes depending on the spiral-inducing force of the chiral agent described above. For example, as will be described later, a first region in which the orientation state of the liquid crystal compound twisted and oriented along a spiral axis extending along the thickness direction is fixed, and a first region in which the orientation state of the homogenius-oriented liquid crystal compound is fixed are fixed.
  • the absolute value of the weighted average spiral inducing force of the chiral agent in the composition layer formed in step 1A is 0.0.
  • the liquid crystal compound in the composition is homogenically oriented or the liquid crystal compound in the composition layer. Is twisted along a spiral axis extending along the thickness direction.
  • the weighted average spiral-inducing force of the chiral agent is the spiral-inducing force of each chiral agent and the composition of each chiral agent when two or more kinds of chiral agents are contained in the composition. It represents the total value of the product of the concentration (% by mass) in the layer divided by the total concentration (% by mass) of the chiral auxiliary in the composition layer.
  • chiral agent X and chiral agent Y it is represented by the following formula (B).
  • the spiral-inducing force is a positive value.
  • the spiral-inducing force is a negative value. That is, for example, in the case of a chiral agent having a spiral induced force of 10 ⁇ m -1 , when the spiral direction of the spiral induced by the chiral agent is right-handed, the spiral induced force is expressed as 10 ⁇ m -1 . On the other hand, when the spiral direction of the spiral induced by the chiral agent is left-handed, the spiral-induced force is expressed as -10 ⁇ m -1 .
  • FIG. 1 is a schematic cross-sectional view of the substrate 10 and the composition layer 12.
  • the composition layer 12 shown in FIG. 1 contains the chiral agent A and the chiral agent B at the same concentration, the spiral direction induced by the chiral agent A is left-handed, and the chiral agent B induces the chiral agent B. It is assumed that the spiral direction is right-handed.
  • the absolute value of the spiral-inducing force of the chiral agent A and the absolute value of the spiral-inducing force of the chiral agent B are assumed to be the same.
  • the homogenic orientation means that the molecular axis of the liquid crystal compound (for example, the major axis in the case of a rod-shaped liquid crystal compound) is arranged horizontally and in the same orientation with respect to the surface of the composition layer. It refers to the state (optical uniaxiality).
  • the term “horizontal” does not require that the liquid crystal compound be strictly horizontal, but means that the average molecular axis of the liquid crystal compound in the composition layer is oriented at an inclination angle of less than 20 degrees with the surface of the composition layer. It shall be.
  • the same direction does not require that the directions are exactly the same, and when the directions of the slow phase axes are measured at arbitrary 20 positions in the plane, the slow phase axes at 20 points are measured. It is assumed that the maximum difference between the slow-phase axis directions among the two directions (the difference between the two slow-phase axis directions having the maximum difference among the 20 slow-phase axis directions) is less than 10 °. ..
  • the mode in which the liquid crystal compound LC is homogenically oriented is described in FIG. 1, it is not limited to this mode as long as the liquid crystal compound is in a predetermined orientation state, and for example, the composition is described in detail later.
  • the liquid crystal compound may be twist-oriented along a spiral axis extending along the thickness direction of the material layer.
  • Step 3A is a step of irradiating the composition layer with light for 50 seconds or less and 300 mJ / cm 2 or less under the condition of an oxygen concentration of 1% by volume or more after the step 2A.
  • the mechanism of this process will be described with reference to the drawings.
  • step 3A under the condition that the oxygen concentration is 1% by volume or more, light is irradiated from the direction opposite to the composition layer 12 side of the substrate 10 (the direction of the white arrow in FIG. 2). I do.
  • the light irradiation is carried out from the substrate 10 side in FIG. 2, it may be carried out from the composition layer 12 side.
  • the surface of the upper region 12B is on the air side, so that the upper region 12B
  • the oxygen concentration in the lower region 12A is high, and the oxygen concentration in the lower region 12A is low. Therefore, when the composition layer 12 is irradiated with light, the polymerization of the liquid crystal compound easily proceeds in the lower region 12A, and the orientation state of the liquid crystal compound is fixed.
  • the chiral agent A is also present in the lower region 12A, and the chiral agent A is also exposed to light, and the spiral inducing force changes.
  • the alignment state of the liquid crystal compound is fixed in the lower region 12A, even if the step 4A of heat-treating the light-irradiated composition layer, which will be described later, is performed, the orientation state of the liquid crystal compound remains. No change occurs.
  • the oxygen concentration is high in the upper region 12B, even if light irradiation is performed, the polymerization of the liquid crystal compound is inhibited by the oxygen, and the polymerization is difficult to proceed.
  • step 4A described later the orientation state of the liquid crystal compound changes along the changed spiral-induced force. That is, by carrying out step 3A, the fixation of the orientation state of the liquid crystal compound is likely to proceed in the substrate-side region (lower region) of the composition layer. Further, in the region opposite to the substrate side (upper region) of the composition layer, the fixation of the orientation state of the liquid crystal compound is difficult to proceed, and the spiral inducing force changes according to the exposed chiral agent A. Will be.
  • Step 3A is carried out under the condition that the oxygen concentration is 1% by volume or more.
  • the oxygen concentration is preferably 2% by volume or more, more preferably 5% by volume or more, in that regions having different orientation states of the liquid crystal compounds are likely to be formed in the optically anisotropic layer.
  • the upper limit is not particularly limited, but 100% by volume can be mentioned.
  • the light irradiation time in the step 3A is 50 seconds or less, and is preferably 30 seconds or less, more preferably 10 seconds or less, from the viewpoint of easy formation of a predetermined optically anisotropic layer and productivity.
  • the lower limit is not particularly limited, but from the viewpoint of curing the liquid crystal compound, 0.1 seconds or more is preferable, and 0.2 seconds or more is more preferable.
  • the irradiation amount of light irradiation in step 3A is 300 mJ / cm 2 or less, preferably 250 mJ / cm 2 or less, and 200 mJ / cm 2 or less from the viewpoint of easy formation of a predetermined optically anisotropic layer and productivity. Is more preferable.
  • the lower limit is not particularly limited, but from the viewpoint of curing the liquid crystal compound, 1 mJ / cm 2 or more is preferable, and 5 mJ / cm 2 or more is more preferable. If the time and amount of light irradiation do not meet the above requirements, the predetermined optically anisotropic layer cannot be formed.
  • the light irradiation in step 3A in the first embodiment is preferably carried out at 15 to 70 ° C. (preferably 25 to 50 ° C.).
  • the light used for light irradiation may be any light that is exposed to the chiral agent A. That is, the light used for light irradiation is not particularly limited as long as it is an active ray or radiation that changes the spiral-inducing force of the chiral agent A. Examples include ultraviolet rays, X-rays, ultraviolet rays, and electron beams. Of these, ultraviolet rays are preferable.
  • Step 4A is a step of subjecting the composition layer to a heat treatment at a temperature higher than that at the time of light irradiation after the step 3A.
  • the orientation state of the liquid crystal compound changes in the region where the spiral-inducing force of the chiral agent A in the composition layer irradiated with light changes.
  • the composition layer after step 3A is heat-treated at a temperature higher than that at the time of irradiation to orient the liquid crystal compound in the composition layer not fixed in step 3A. It is a process to make it. In the following, the mechanism of this process will be described with reference to the drawings.
  • step 3A when step 3A is carried out on the composition layer 12 shown in FIG. 1, the orientation state of the liquid crystal compound is fixed in the lower region 12A, whereas the orientation state of the liquid crystal compound is fixed in the upper region 12B.
  • the polymerization is difficult to proceed, and the orientation of the liquid crystal compound is not fixed.
  • the spiral-inducing force of the chiral agent A changes.
  • the force for twisting the liquid crystal compound changes in the upper region 12B as compared with the state before light irradiation. This point will be described in more detail.
  • the chiral agent A and the chiral agent B are present in the composition layer 12 shown in FIG.
  • the spiral direction induced by the chiral agent A is left-handed, and the chiral agent B causes the composition layer 12.
  • the induced spiral direction is right-handed.
  • the absolute value of the spiral-inducing force of the chiral agent A and the absolute value of the spiral-inducing force of the chiral agent B are the same. Therefore, the weighted average spiral inducing force of the chiral agent in the composition layer before light irradiation is 0.
  • the vertical axis represents “the spiral-inducing force of the chiral agent ( ⁇ m -1 ) ⁇ the concentration of the chiral agent (mass%)”, and the farther the value is from zero, the larger the spiral-inducing force.
  • the relationship between the chiral agent A and the chiral agent B in the composition layer before light irradiation corresponds to the time when the light irradiation amount is 0, and "the spiral inducing force of the chiral agent A ( ⁇ m -1 ) ⁇ ".
  • the absolute value of "concentration of chiral agent A (% by mass)” and “spiral inducing force of chiral agent B ( ⁇ m -1 ) x concentration of chiral agent B (% by mass)” correspond to the same state. That is, the spiral-inducing forces of both the chiral agent A that induces left-handed winding and the chiral agent B that induces right-handed winding are canceled out.
  • the composition layer 12 after the step 3A in which such a change in the weighted average spiral inducing force is generated is heat-treated to promote the reorientation of the liquid crystal compound, as shown in FIG. 3, the upper side is shown.
  • the liquid crystal compound LC is twist-oriented along a spiral axis extending along the thickness direction of the composition layer 12.
  • the polymerization of the liquid crystal compound proceeds during the step 3A and the orientation state of the liquid crystal compound is fixed, so that the reorientation of the liquid crystal compound is not possible. Does not progress.
  • step 4A a plurality of regions having different orientation states of the liquid crystal compounds are formed along the thickness direction of the composition layer.
  • chiral agent A a chiral agent whose spiral-inducing force is increased by light irradiation may be used.
  • the spiral-inducing force induced by the chiral agent A increases due to light irradiation, and the liquid crystal compound is twisted or oriented in the swirling direction induced by the chiral agent A.
  • FIGS. 4 and 5 above the mode in which the chiral agent A and the chiral agent B are used in combination has been described, but the mode is not limited to this mode. For example, it may be an embodiment in which two kinds of chiral agents A are used.
  • the chiral agent A1 that induces left-handed winding and the chiral agent A2 that induces right-handed winding may be used in combination.
  • the chiral agents A1 and A2 may be chiral agents whose spiral-inducing force increases or may be chiral agents whose spiral-inducing force decreases, respectively.
  • a chiral agent that induces left-handed winding and whose spiral-inducing force increases by light irradiation and a chiral agent that induces right-handed winding and whose spiral-inducing force decreases by light irradiation are used in combination. You may.
  • the heat treatment is carried out at a temperature higher than that at the time of light irradiation.
  • the difference between the temperature of the heat treatment and the temperature at the time of light irradiation is preferably 5 ° C. or higher, more preferably 10 to 110 ° C., and even more preferably 20 to 110 ° C.
  • the temperature of the heat treatment is preferably higher than the temperature at the time of light irradiation, and is preferably a temperature at which the unfixed liquid crystal compound in the composition layer is oriented, and more specifically, it is often 35 to 250 ° C. More often, the temperature is 50 to 150 ° C., more often, the temperature is more than 50 ° C. and 150 ° C. or lower, and 60 to 130 ° C. is particularly common.
  • the heating time is often 0.01 to 60 minutes, and more often 0.03 to 5 minutes.
  • the absolute value of the weighted average spiral-inducing force of the chiral agent in the composition layer after light irradiation is not particularly limited, but the weighted average spiral-inducing force of the chiral agent in the composition layer after light irradiation and before light irradiation.
  • the absolute value of the difference from the weighted average spiral inducing force is preferably 0.05 ⁇ m -1 or more, more preferably 0.05 to 10.0 ⁇ m -1 , and even more preferably 0.1 to 10.0 ⁇ m -1 .
  • Step 5A is a step of subjecting the composition layer to a curing treatment after step 4A to form an optically anisotropic layer having a plurality of regions having different orientation states of the liquid crystal compounds along the thickness direction.
  • the orientation state of the liquid crystal compound in the composition layer is fixed, and as a result, a predetermined optically anisotropic layer is formed.
  • the composition layer 12 shown in FIG. 3 described above is cured, the alignment state of the liquid crystal compound twisted and oriented along the spiral axis extending along the thickness direction is fixed.
  • An optically anisotropic layer having a first region thereof and a second region formed by fixing the orientation state of the homogenically oriented liquid crystal compound along the thickness direction is formed.
  • the method of the curing treatment is not particularly limited, and examples thereof include a photo-curing treatment and a thermosetting treatment.
  • the light irradiation treatment is preferable, and the ultraviolet irradiation treatment is more preferable.
  • a light source such as an ultraviolet lamp is used for ultraviolet irradiation.
  • the irradiation amount of light (for example, ultraviolet rays) is not particularly limited, but is generally preferably about 100 to 800 mJ / cm 2 .
  • the atmosphere at the time of light irradiation is not particularly limited, and light irradiation may be carried out under air, or light irradiation may be carried out under an inert atmosphere. In particular, light irradiation is preferably carried out at an oxygen concentration of less than 1% by volume.
  • the temperature conditions at the time of photocuring are not particularly limited as long as the temperature is such that the orientation state of the liquid crystal compound in step 4A is maintained, and the temperature and light of the heat treatment in step 4A are sufficient.
  • the difference from the temperature at the time of the curing treatment is preferably 100 ° C. or less, more preferably 80 ° C. or less. It is preferable that the temperature of the heat treatment in step 4A and the temperature of the photohardening treatment are the same, or the temperature of the photohardening treatment is lower.
  • the orientation state of the liquid crystal compound is fixed.
  • the "fixed" state is the most typical and preferable state in which the orientation of the liquid crystal compound is maintained. It is not limited to this, and specifically, in the temperature range of 0 to 50 ° C., and more severely, -30 to 70 ° C., the layer has no fluidity and is oriented by an external field or an external force. It is more preferable that the fixed orientation morphology can be kept stable without causing a change. In the optically anisotropic layer, it is no longer necessary for the composition in the layer to finally exhibit liquid crystallinity.
  • the thickness of the optically anisotropic layer is not particularly limited, but is preferably 0.05 to 10 ⁇ m, more preferably 0.1 to 8.0 ⁇ m, and even more preferably 0.2 to 6.0 ⁇ m.
  • An optically anisotropic layer having a second region formed by fixing the compound along the thickness direction is produced, but the present invention is not limited to the above embodiment.
  • the twisting orientation of the liquid crystal compound may be a left twist. That is, the direction of the twist orientation of the liquid crystal compound may be a left twist (counterclockwise twist) or a right twist (clockwise twist).
  • the orientation state of the liquid crystal compound in the second region may be an orientation other than the homogenius orientation, and when the liquid crystal compound is a rod-shaped liquid crystal compound, the orientation state thereof is, for example, a nematic orientation (nematic phase).
  • nematic orientation nematic phase
  • smectic orientation state forming smectic phase
  • cholesteric orientation state forming cholesteric phase
  • hybrid orientation hybrid orientation.
  • examples of the orientation state include nematic orientation, columnar orientation (a state in which a columnar phase is formed), and cholesteric orientation.
  • a known method can be mentioned. For example, a method of observing the cross section of the optically anisotropic layer with a polarizing microscope to identify the orientation state of the liquid crystal compound can be mentioned.
  • the optically anisotropic layer has regions in which the orientation states of the two liquid crystal compounds are different, but the present invention is not limited to the above embodiment, and the optically anisotropic layer is not limited to the above embodiment. It may have three or more regions in which the orientation state of the liquid crystal compound is different.
  • the optically anisotropic layer has regions having different orientation states of the two liquid crystal compounds, the ratio of the thickness of the thick region of the two regions to the thickness of the thin region of the two regions is particularly high. Although not limited, it is preferably 1 to 9 or less, and more preferably 1 to 4 or less. When the thicknesses of the two regions are the same, the above ratio is 1.
  • the optically anisotropic layer in the first embodiment has a first region in which the orientation state of the liquid crystal compound twisted and oriented along a spiral axis extending along the thickness direction is fixed, and a spiral extending along the thickness direction.
  • the optically anisotropic layer may have a second region along the axis, which is formed by fixing the orientation state of the twist-oriented liquid crystal compound at a twist angle different from that of the first region, along the thickness direction.
  • the spiral-inducing force changed in the region in the composition layer having a high oxygen concentration (upper region 120B in FIG. 7), and after performing step 5A, as a result, the angle of the twist angle of the liquid crystal compound was changed. Different regions can be formed.
  • the optical characteristics in the optically anisotropic layer in the first embodiment are not particularly limited, and the optimum value is selected according to the application.
  • the first region in which the orientation state of the liquid crystal compound twisted and oriented along the spiral axis extending along the thickness direction is fixed and the orientation state of the anisotropically oriented liquid crystal compound, which are produced by the above-mentioned procedure, and the orientation state of the anisotropically oriented liquid crystal compound are described below.
  • the case of an optically anisotropic layer having a second region formed by fixing the above in the thickness direction will be described in detail.
  • the optically anisotropic layer can be suitably applied to a circular polarizing plate. Therefore, it is preferable that the first region satisfies the following formula (1A-1). Equation (1A-1) 100 nm ⁇ ⁇ n1d1 ⁇ 240 nm Among them, it is more preferable to satisfy the formula (1A-2), and it is further preferable to satisfy the formula (1A-3). Equation (1A-2) 120 nm ⁇ ⁇ n 1d1 ⁇ 220 nm Equation (1A-3) 140 nm ⁇ ⁇ n 1d1 ⁇ 200 nm
  • the absolute value of the twist angle of the liquid crystal compound in the first region is not particularly limited, but 50 to 110 ° is preferable, and 60 to 100 ° is more preferable, in that the optically anisotropic layer can be suitably applied to the circular polarizing plate.
  • the twisting orientation of the liquid crystal compound means that one surface of the first region (the surface on the substrate 10 side in FIG. 3) to the other surface (the substrate in FIG. 3) is oriented with the thickness direction of the first region as the axis. It is intended that the liquid crystal compound up to (the surface opposite to the 10 side) is twisted.
  • the twist angle is the angle formed by the molecular axis of the liquid crystal compound on one surface of the first region (long axis in the case of a rod-shaped liquid crystal compound) and the molecular axis of the liquid crystal compound on the other surface of the first region. Means.
  • the twist angle is measured by using Axoscan of Axometrics and using the device analysis software of Axoschan.
  • the optically anisotropic layer is suitably applied to the circular polarizing plate.
  • the second region satisfies the following formula (2A-1). Equation (2A-1) 100 nm ⁇ ⁇ n2d2 ⁇ 240 nm Among them, it is more preferable to satisfy the formula (2A-2), and it is further preferable to satisfy the formula (2A-3). Equation (2A-2) 120 nm ⁇ ⁇ n 2d 2 ⁇ 220 nm Equation (2A-3) 140 nm ⁇ ⁇ n 2d2 ⁇ 200 nm
  • the second region is a region formed by fixing the orientation state of the homogenically oriented liquid crystal compound.
  • the definition of homogenius orientation is as described above.
  • ⁇ n1d1 and ⁇ n2d2 are not particularly limited, -50 to 50 nm is preferable, and -30 to 30 nm is more preferable in that the optically anisotropic layer can be suitably applied to a circular polarizing plate.
  • two regions are included in the optically anisotropic layer according to the first embodiment, in which the orientation state of the liquid crystal compound twisted and oriented along the spiral axis extending along the thickness direction is fixed, and one region is defined as a region.
  • a and the other region are the region B, when the thickness of the region A is dA and the refractive index anisotropic layer of the region A measured at a wavelength of 550 nm is ⁇ A, the region A is a circular optically anisotropic layer. It is preferable to satisfy the following formula (3A-1) in that it can be suitably applied to a polarizing plate.
  • Equation (3A-1) 205 nm ⁇ ⁇ nAdA ⁇ 345 nm Among them, it is more preferable to satisfy the formula (3A-2), and it is further preferable to satisfy the formula (3A-3).
  • Equation (3A-2) 225 nm ⁇ ⁇ nAdA ⁇ 325 nm
  • Equation (3A-3) 245 nm ⁇ ⁇ nAdA ⁇ 305 nm
  • the absolute value of the twist angle of the liquid crystal compound in the region A is not particularly limited, but it is preferably more than 0 ° and 60 ° or less, more preferably 10 to 50 °, in that the optically anisotropic layer can be suitably applied to the circular polarizing plate. ..
  • the region B can be suitably applied to the circularly polarizing plate. It is preferable to satisfy 4A-1). Equation (4A-1) 70 nm ⁇ ⁇ nB dB ⁇ 210 nm Among them, it is more preferable to satisfy the formula (4A-2), and it is further preferable to satisfy the formula (4A-3). Equation (4A-2) 90 nm ⁇ ⁇ nB dB ⁇ 190 nm Equation (4A-3) 110 nm ⁇ ⁇ nB dB ⁇ 170 nm
  • the absolute value of the twist angle of the liquid crystal compound in the region B is not particularly limited, but 50 to 110 ° is preferable, and 60 to 100 ° is more preferable, in that the optically anisotropic layer can be suitably applied to the circular polarizing plate.
  • the region where the optically anisotropic layer formed in the first embodiment of the method for producing an optically anisotropic layer of the present invention differs in the orientation state of the liquid crystal compound along the thickness direction is 2
  • the two regions are referred to as region X and region Y
  • the slow axis on the surface of the region X on the region Y side and the slow axis on the surface of the region Y on the region X side are parallel. In many cases.
  • optical properties in the optically anisotropic layer in the first embodiment are not limited to those described above, and for example, when the optically anisotropic layer has two regions in which the orientation state of the liquid crystal compound is different along the thickness direction.
  • the two regions satisfy the optical characteristics (relationship between the twist angle of the liquid crystal compound, ⁇ nd, ReB, and the slow axis) of the first optically anisotropic layer and the second optically anisotropic layer described in Patent No. 5960743, respectively. Is preferable.
  • the two regions are the first optically anisotropic layer and the second optically anisotropic layer described in Patent No. 5753922. It is preferable to satisfy the optical characteristics (relationship between the twist angle of the liquid crystal compound, ⁇ n1d1, ⁇ n2d2, and the slow axis).
  • the optically anisotropic layer in the first embodiment preferably exhibits reverse wavelength dispersibility. That is, Re (450), which is an in-plane retardation measured at a wavelength of 450 nm of the optically anisotropic layer, and Re (550), which is an in-plane retardation measured at a wavelength of 550 nm of the optically anisotropic layer, are optically anisotropic. It is preferable that Re (650), which is the in-plane retardation measured at a layer wavelength of 650 nm, has a relationship of Re (450) ⁇ Re (550) ⁇ Re (650).
  • the optical characteristics of the optically anisotropic layer in the first embodiment are not particularly limited, but it is preferable that the optical anisotropic layer functions as a ⁇ / 4 plate.
  • the ⁇ / 4 plate is a plate having a function of converting linearly polarized light of a specific wavelength into circularly polarized light (or converting circularly polarized light into linearly polarized light), and the in-plane retardation Re ( ⁇ ) at a specific wavelength of ⁇ nm is Re.
  • a plate (optically anisotropic layer) that satisfies ( ⁇ ) ⁇ / 4.
  • This equation may be achieved at any wavelength in the visible light region (eg, 550 nm), but the in-plane retardation Re (550) at a wavelength of 550 nm satisfies the relationship 110 nm ⁇ Re (550) ⁇ 180 nm. Is preferable.
  • the second embodiment of the method for producing an optically anisotropic layer of the present invention comprises the following steps 1B to 5B.
  • an optically anisotropic layer having a region formed by fixing the cholesteric liquid crystal phase is formed.
  • Step 1B Forming a composition layer containing at least a photosensitive chiral agent whose spiral-inducing force changes by light irradiation and a liquid crystal compound having a polymerizable group
  • Step 2B Heat-treating the composition layer.
  • Step 3B to form a cholesteric liquid crystal phase by orienting the liquid crystal compound in the composition layer After step 2B, light is applied to the composition layer under the condition of an oxygen concentration of 1% by volume or more.
  • the total content of the chiral agent (total content of all chiral agents) in the composition layer is more than 5.0% by mass with respect to the total mass of the liquid crystal compound. Is preferable.
  • the difference between the first embodiment and the second embodiment is mainly in the content of the chiral agent.
  • Step 1B is a step of forming a composition layer containing at least a photosensitive chiral agent whose spiral-inducing force is changed by light irradiation and a liquid crystal compound having a polymerizable group.
  • a composition layer to be subjected to a light irradiation treatment described later is formed.
  • the chiral agent (chiral agent A and chiral agent B) and the liquid crystal compound contained in the composition layer are as described in step 1A.
  • the composition layer may contain other components other than the chiral agent and the liquid crystal compound.
  • a chiral agent is contained in the composition layer so that the cholesteric liquid crystal phase is formed in step 2B described later.
  • the total content of the chiral agent (total content of all chiral agents) in the composition layer is not particularly limited, but the total mass of the liquid crystal compound is easy to control in that the orientation state of the liquid crystal compound is easily controlled.
  • more than 5.0% by mass is preferable, 5.5% by mass or more is more preferable, and 6.0% by mass or more is further preferable.
  • the upper limit is not particularly limited, but is preferably 25% by mass or less, more preferably 20% by mass or less, still more preferably 15% by mass or less.
  • the content of the chiral agent A in the chiral agent is not particularly limited, but is preferably 5 to 95% by mass, preferably 10 to 90% by mass, based on the total mass of the chiral agent, in that the orientation state of the liquid crystal compound can be easily controlled. Is more preferable.
  • the absolute value of the spiral-inducing force of the chiral agent in the composition layer formed in step 1B is preferably 10 ⁇ m -1 or more, more preferably 15 ⁇ m -1 or more, still more preferably 20 ⁇ m -1 or more.
  • the upper limit is not particularly limited, but in many cases it is 250 ⁇ m -1 or less, and in many cases it is 200 ⁇ m -1 or less.
  • the absolute value of the weighted average spiral inducing force of the chiral agents in the composition layer formed in step 1B is preferably within the above range.
  • the liquid crystal compound in the composition is cholesterically oriented by the step 2B.
  • the definition of the weighted average spiral induced force is as described above.
  • Examples of the method for forming the composition layer in step 1B include the same forming method as the method for forming the composition layer in step 1A described above.
  • Step 2B is a step of heat-treating the composition layer to orient the liquid crystal compound in the composition layer to form a cholesteric liquid crystal phase.
  • the liquid crystal compound in the composition layer is in a predetermined orientation state.
  • the heat treatment conditions the optimum conditions are selected according to the liquid crystal compound used. Among them, the heating temperature is often 25 to 250 ° C, more often 40 to 150 ° C, and even more often 50 to 130 ° C.
  • the heating time is often 0.1 to 60 minutes, and more often 0.2 to 5 minutes.
  • Step 3B is a step of irradiating the composition layer with light for 50 seconds or less and 300 mJ / cm 2 or less under the condition of an oxygen concentration of 1% by volume or more after the step 2B.
  • the embodiment shown in FIG. 8 corresponds to the embodiment in which the liquid crystal compound forms a cholesteric liquid crystal phase.
  • step 3B under the condition that the oxygen concentration is 1% by volume or more, light is irradiated from the direction opposite to the composition layer 220 side of the substrate 10 (the direction of the white arrow in FIG. 8). I do. Although the light irradiation is carried out from the substrate 10 side in FIG.
  • the composition layer 220 side it may be carried out from the composition layer 220 side.
  • the surface of the upper region 220B is on the air side, so that the upper region 220B
  • the oxygen concentration in the lower region 220A is high, and the oxygen concentration in the lower region 220A is low. Therefore, when the composition layer 220 is irradiated with light, the polymerization of the liquid crystal compound easily proceeds in the lower region 220A, and the orientation state of the liquid crystal compound is fixed.
  • the chiral agent A is also present in the lower region 220A, and the chiral agent A is also exposed to light, and the spiral inducing force changes.
  • the orientation state of the liquid crystal compound is fixed in the lower region 220A, even if step 4B of heat-treating the light-irradiated composition layer, which will be described later, is performed, the orientation state of the liquid crystal compound remains. No change occurs.
  • the oxygen concentration is high in the upper region 220B, even if light irradiation is performed, the polymerization of the liquid crystal compound is inhibited by the oxygen, and the polymerization is difficult to proceed.
  • step 4B described later the orientation state of the liquid crystal compound changes along the changed spiral-induced force. That is, by carrying out step 3B, the fixation of the orientation state of the liquid crystal compound is likely to proceed in the substrate-side region (lower region) of the composition layer. Further, in the region opposite to the substrate side (upper region) of the composition layer, the fixation of the orientation state of the liquid crystal compound is difficult to proceed, and the spiral inducing force changes according to the exposed chiral agent A. Will be.
  • step 3B The various conditions of light irradiation (oxygen concentration, irradiation time, irradiation amount, etc.) in step 3B are the same as the various conditions of light irradiation in step 3A described above.
  • Step 4B is a step of subjecting the composition layer to a heat treatment at a temperature higher than that at the time of light irradiation after the step 3B.
  • the orientation state of the liquid crystal compound changes in the region where the spiral-inducing force of the chiral agent A in the composition layer irradiated with light changes.
  • the composition layer after step 3B is heat-treated at a temperature higher than that at the time of irradiation to orient the liquid crystal compound in the composition layer not fixed in step 3B. It is a process to make it.
  • the mechanism of this process will be described with reference to the drawings.
  • step 3B when step 3B is carried out on the composition layer 220 shown in FIG. 8, the orientation state of the liquid crystal compound is fixed in the lower region 220A, whereas the orientation state of the liquid crystal compound is fixed in the upper region 220B.
  • the polymerization is difficult to proceed, and the orientation of the liquid crystal compound is not fixed.
  • the spiral-inducing force of the chiral agent A changes in the upper region 220B.
  • the force for twisting the liquid crystal compound changes in the upper region 220B as compared with the state before light irradiation. This point will be described in more detail.
  • the composition layer 220 contains the chiral agent A whose induced spiral direction is left-handed and whose spiral-inducing force is reduced by light irradiation will be described in detail.
  • the spiral inducing force of the chiral agent A decreases depending on the amount of light irradiation as shown in FIG. 10
  • the spiral inducing force of the chiral agent in the upper region 220B is small.
  • the composition layer 220 after the step 3B in which such a change in the spiral inducing force is generated is heat-treated to promote the reorientation of the liquid crystal compound, as shown in FIG.
  • the upper region 220B In the spiral pitch of the cholesteric liquid crystal layer becomes large.
  • the polymerization of the liquid crystal compound proceeds during step 3B and the orientation state of the liquid crystal compound is fixed, so that the reorientation of the liquid crystal compound is not possible. Does not progress.
  • step 4B a plurality of cholesteric liquid crystal phases having different spiral pitches are formed along the thickness direction of the composition layer.
  • chiral agent A a chiral agent whose spiral-inducing force is increased by light irradiation may be used.
  • FIGS. 8 and 9 an embodiment in which the chiral agent induced as the chiral agent A has a left-handed spiral direction has been described, but the present invention is not limited to this embodiment.
  • a chiral agent whose spiral direction induced as the chiral agent A is right-handed may be used.
  • FIGS. 8 and 9 the embodiment in which only one kind of chiral agent A is used has been described, but the embodiment is not limited to this embodiment. For example, it may be an embodiment in which two kinds of chiral agents A are used, or an embodiment in which the chiral agent A and the chiral agent B are used in combination.
  • the heat treatment is carried out at a temperature higher than that at the time of light irradiation.
  • the difference between the temperature of the heat treatment and the temperature at the time of light irradiation is preferably 5 ° C. or higher, more preferably 10 to 110 ° C., and even more preferably 20 to 110 ° C.
  • the temperature of the heat treatment is higher than the temperature at the time of light irradiation, and is preferably a temperature at which the non-fixed liquid crystal compound in the composition layer is oriented, and more specifically, it is often 40 to 250 ° C. More often, the temperature is 50 to 150 ° C., more often, the temperature is more than 50 ° C. and 150 ° C. or lower, and 60 to 130 ° C. is particularly common.
  • the heating time is often 0.01 to 60 minutes, and more often 0.03 to 5 minutes.
  • the absolute value of the spiral-inducing force of the chiral agent in the composition layer after light irradiation is not particularly limited, but the spiral-inducing force of the chiral agent in the composition layer after light irradiation and the spiral-inducing force before light irradiation are used.
  • the absolute value of the difference is preferably 0.05 ⁇ m -1 or more, more preferably 0.05 to 10.0 ⁇ m -1 , and even more preferably 0.1 to 10.0 ⁇ m -1 .
  • the absolute value of the difference between the weighted average spiral-inducing force of the chiral agents in the composition layer after light irradiation and the weighted average spiral-inducing force before light irradiation is preferable, 0.05 to 10.0 ⁇ m -1 is more preferable, and 0.1 to 10.0 ⁇ m -1 is even more preferable.
  • Step 5B is a step of subjecting the composition layer to a curing treatment after step 4B to form an optically anisotropic layer having a plurality of regions having different orientation states of the liquid crystal compounds along the thickness direction.
  • the orientation state of the liquid crystal compound in the composition layer is fixed, and as a result, a predetermined optically anisotropic layer is formed.
  • the optically anisotropic layer is formed by fixing the cholesteric liquid crystal phase, and has a plurality of regions in which the spiral pitch of the cholesteric liquid crystal phase is different along the thickness direction. Layers are formed. The length of the spiral pitch in each region formed is often constant.
  • this step it is an optically anisotropic layer in which the cholesteric liquid crystal phase is fixed, and has a plurality of regions in which the spiral pitch of the cholesteric liquid crystal phase is different along the thickness direction, and each region.
  • An optically anisotropic layer having a constant spiral pitch can be formed.
  • Examples of the curing treatment method in step 5B include the curing treatment method in step 5A.
  • the thickness of the optically anisotropic layer is not particularly limited, but is preferably 0.05 to 10 ⁇ m, more preferably 0.1 to 8.0 ⁇ m, and even more preferably 0.2 to 6.0 ⁇ m.
  • the optically anisotropic layer formed by the above method which is formed by fixing the cholesteric liquid crystal phase and has a plurality of regions having different spiral pitches of the cholesteric liquid crystal phase along the thickness direction.
  • the selective reflection center wavelength derived from the cholesteric liquid crystal phase in each region is different.
  • the optically anisotropic layer has an optical difference having a region in which a cholesteric liquid crystal phase that reflects blue light is fixed and a region in which a cholesteric liquid crystal phase that reflects green light is fixed along the thickness direction.
  • the selective reflection center wavelength is defined as the half-value transmittance expressed by the following formula, where T min (%) is the minimum value of the transmittance of the target object (member): T 1 . It refers to the average value of two wavelengths indicating / 2 (%).
  • T 1/2 100- (100-T min ) ⁇ 2
  • the light in the wavelength range of 420 nm or more and less than 500 nm is blue light (B light)
  • the light in the wavelength range of 500 nm or more and less than 600 nm is green light (G light)
  • the light has a wavelength of 600 nm or more and less than 700 nm.
  • the light in the region is red light (R light).
  • the optically anisotropic layer has regions in which the orientation states of the two liquid crystal compounds are different, but the present invention is not limited to the above embodiment, and the optically anisotropic layer is not limited to the above embodiment. It may have three or more regions in which the orientation state of the liquid crystal compound is different. As described above, the optically anisotropic layer having three or more regions having different liquid crystal compound orientation states can be formed, for example, by changing the conditions of step 3B and performing the process a plurality of times.
  • the optically anisotropic layer as described above includes, for example, a region in which the cholesteric liquid crystal phase that reflects blue light is fixed and a region in which the cholesteric liquid crystal phase that reflects green light is fixed along the thickness direction. And an optically anisotropic layer having a region formed by fixing a cholesteric liquid crystal phase that reflects red light.
  • the third embodiment of the method for producing an optically anisotropic layer of the present invention comprises the following steps 1C to 5C.
  • the optically anisotropic layer has a region in which the orientation direction of the liquid crystal compound is inclined or perpendicular to the layer surface and the orientation state of the liquid crystal compound is fixed. It is formed.
  • Step 1C Forming a composition layer containing a photosensitive compound whose polarity changes by light irradiation and a liquid crystal compound having a polymerizable group
  • Step 2C The composition layer is heat-treated to be contained in the composition layer.
  • Step 3C for orienting the liquid crystal compound After step 2C, the composition layer is irradiated with light for 50 seconds or less and at 300 mJ / cm 2 or less under the condition of an oxygen concentration of 1% by volume or more.
  • Step 4C After step 3C, the composition layer is heat-treated at a temperature higher than that at the time of light irradiation.
  • Step 5C After step 4C, the composition layer is cured and the orientation state of the liquid crystal compound is applied. Step of forming an optically anisotropic layer having a plurality of regions having different regions along the thickness direction
  • a photosensitive compound whose polarity is changed by light irradiation is used.
  • Step 1C is a step of forming a composition layer containing a photosensitive compound whose polarity changes with light irradiation and a liquid crystal compound having a polymerizable group.
  • a composition layer to be subjected to a light irradiation treatment described later is formed.
  • the liquid crystal compound contained in the composition layer is as described in step 1A.
  • the composition layer may contain other components as described in the above-mentioned step 1A.
  • the composition layer of step 1C contains a photosensitive compound whose polarity changes with light irradiation (hereinafter, also referred to as “specific photosensitive compound”).
  • the photosensitive compound whose polarity changes by light irradiation is a compound whose polarity changes before and after light irradiation.
  • the composition layer containing such a specific photosensitive compound is irradiated with light in step 1C, the polarity of the specific compound changes in the region on the air side in the composition layer, and step 4C
  • the orientation direction of the liquid crystal compound becomes inclined or perpendicular to the layer surface as the polarity changes.
  • the change in the polarity of the specific photosensitive compound may be a change that makes the specific photosensitive compound hydrophilic or a change that makes the specific photosensitive compound hydrophobic.
  • the change of hydrophilicity is preferable from the viewpoint that the orientation state of the liquid crystal compound can be easily formed in which the orientation direction of the liquid crystal compound is inclined or perpendicular to the layer surface.
  • the specific photosensitive compound that becomes hydrophilic by light irradiation a compound having a group that produces a hydrophilic group by light irradiation is preferable.
  • the type of the hydrophilic group is not particularly limited and may be any of a cationic group, an anionic group and a nonionic group, and more specifically, a carboxylic acid group, a sulfonic acid group and a phosphonic acid group. Examples thereof include an amino group, an ammonium group, an amide group, a thiol group, and a hydroxy group.
  • the specific photosensitive compound preferably has a fluorine atom or a silicon atom.
  • the specific photosensitive compound has the above-mentioned atoms, the specific photosensitive compound is likely to be unevenly distributed near the surface of the composition layer, and a desired optically anisotropic layer is likely to be formed.
  • a compound represented by the formula (X) is preferable.
  • T represents an n + m-valent aromatic hydrocarbon group.
  • Sp represents a single bond or a divalent linking group.
  • Hb represents a fluorine-substituted alkyl group having 4 to 30 carbon atoms.
  • m represents an integer from 1 to 4 and represents n represents an integer from 1 to 4 and represents A represents a group represented by the following formula (Y).
  • R 1 to R 5 independently represent a hydrogen atom or a monovalent substituent. * Represents a binding site.
  • the formula (X) when a plurality of the above Sp, the above Hb, or the above A are present, the plurality of Sps, the plurality of Hbs, or the plurality of A's are each present. It may be the same or different.
  • T represents an n + m-valent aromatic hydrocarbon group.
  • the aromatic hydrocarbon group is not particularly limited as long as it is a group obtained by removing n + m hydrogen atoms from the aromatic hydrocarbon ring, but the number of carbon atoms is preferably 6 to 22, and more preferably 6 to 14. It is preferably 6 to 10, and more preferably 6 to 10.
  • the aromatic hydrocarbon group is particularly preferably a benzene ring.
  • substituents examples include an alkyl group (for example, an alkyl group having 1 to 8 carbon atoms), an alkoxy group (for example, an alkoxy group having 1 to 8 carbon atoms), and a halogen atom (for example, a fluorine atom, a chlorine atom and a bromine atom). , And an iodine atom), a cyano group, and an acyloxy group (eg, an acetoxy group).
  • Sp represents a single bond or a divalent linking group, and is preferably a divalent linking group.
  • the divalent linking group is not particularly limited, but is a linear or branched alkylene group (preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, still more preferably 1 to 6 carbon atoms). Chain or branched alkenylene groups (preferably 2 to 20, more preferably 2 to 10, more preferably 2 to 6 carbons), straight or branched alkinylene groups (preferably 2 to 20, carbons 2-20, More preferably 2 to 10 carbon atoms, still more preferably 2 to 6 carbon atoms), or a group in which one or more -CH 2 -is substituted with the "divalent organic group" shown below.
  • divalent organic group selected from the group consisting of.
  • divalent organic group one or two or more -CH 2 -are substituted with the "divalent organic group" shown below from the viewpoint of further improving the solubility, and the number of carbon atoms is 1. ⁇ 10 alkylene groups are preferred.
  • R 6 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
  • Hb represents a fluorine-substituted alkyl group having 4 to 30 carbon atoms. Hb preferably has 4 to 20 carbon atoms, and more preferably 4 to 10 carbon atoms.
  • the fluorine-substituted alkyl group may be a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms, or a fluoroalkyl group in which a part of hydrogen atoms is substituted with fluorine atoms. good.
  • the fluorine-substituted alkyl group may be chain-shaped, branched or cyclic, but is preferably chain-shaped or branched, and more preferably chain-shaped.
  • As the fluorine-substituted alkyl group a structure that is a perfluoroalkyl group is preferable.
  • q is preferably 0 to 6, more preferably 0 to 4, and even more preferably 0 to 3.
  • r is preferably 1 to 6, more preferably 1 to 4, and even more preferably 1 to 3. Further, the total number of carbon atoms in the portions other than the perfluoro group is preferably 10 or less.
  • n and m each independently represent an integer of 1 to 4. From the viewpoint of further progress of hydrophilization, n is preferably 2 or more. m is preferably 1 to 3, and more preferably 2.
  • A represents a group represented by the above formula (Y).
  • the formula (Y) will be described.
  • R 1 to R 5 independently represent a hydrogen atom or a monovalent substituent.
  • the monovalent substituent represented by R 1 to R 5 is not particularly limited.
  • Examples of the monovalent substituent represented by R 1 to R 4 include a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), a hydroxyl group, a cyano group, and a substituted or unsubstituted amino group (for example).
  • a halogen atom for example, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom
  • a hydroxyl group for example, a cyano group, and a substituted or unsubstituted amino group (for example).
  • -N ( RA ) 2 the two RAs independently represent a hydrogen atom or a monovalent organic group (for example, an alkyl group having 1 to 5 carbon atoms as a monovalent organic group).
  • An alkoxy group having 1 to 8 carbon atoms for example, a methoxy group and an ethoxy group
  • RC RB is hydrogen
  • It represents an atomic or monovalent organic group (as a monovalent organic group, for example, an alkyl group having 1 to 5 carbon atoms)
  • RC is a monovalent organic group (as a monovalent organic group, for example, carbon).
  • Represents an alkyl group of number 1-5)) or -C ( O) N ( RD ) 2 (two RDs are independent hydrogen atoms or monovalent organic groups (eg, carbon number).
  • the above Sp A and the above Hb A are synonymous with Sp and Hb of the above formula (X), respectively, and the preferred embodiments thereof are also the same.
  • the formula (Y) when a plurality of R 1 to R 4 represent ⁇ Sp A ⁇ Hb A , the plurality of Sp As and the plurality of Hb A are the same. May also be different.
  • R 1 to R 4 are independent from each other in that the decomposition rate of the compound represented by the formula (X) by exposure is accelerated, the hydrophilicity is further promoted, and / or the orientation is further enhanced.
  • -OCH 3 or Sp A -Hb A More preferably, -OCH 3 or Sp A -Hb A.
  • OCH 3 since ether oxygen is contained in the structure (in particular, the position bonded to the benzene ring in the formula (Y) is the ether oxygen), it is represented by the formula (X) by exposure. The decomposition rate of the compound is faster, and the hydrophilization tends to proceed more.
  • -Sp A -Hb A the orientation tends to be further enhanced by the presence of Hb A.
  • R 1 to R 4 are independently of -OCH. It is preferably 3 or Sp B ⁇ Hb B , and more preferably R 2 and R 3 are independently ⁇ OCH 3 or Sp B ⁇ Hb B , respectively.
  • Sp B represents an alkylene group having 1 to 10 carbon atoms in which —CH 2 ⁇ is substituted with —O ⁇ .
  • ether oxygen is contained in the terminal on the side opposite to the side bonded to Hb B in Sp B (in other words, the terminal on the side connected to the benzene ring of the formula (Y)).
  • the effect of accelerating the decomposition rate is obtained more remarkably, and hydrophilization progresses more.
  • —CH 2 ⁇ in the alkylene group is substituted with a plurality of —O—s, it is preferable that —O—s are not adjacent to each other.
  • the alkylene group is more preferably 1 to 7 carbon atoms, further preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms.
  • the alkylene group may be linear or branched, but is preferably linear.
  • the above Hb B represents a fluorine-substituted alkyl group having 4 to 30 carbon atoms.
  • the preferred embodiment of the above Hb B is the same as that of the above-mentioned Hb of the formula (X).
  • the formula (Y) when a plurality of R 1 to R 4 represent ⁇ Sp B ⁇ Hb B , the plurality of Sp Bs and the plurality of Hb Bs are the same. May be different.
  • R 1 to R 4 are-from the viewpoint that the decomposition rate of the compound represented by the formula (X) by exposure is accelerated, the hydrophilicity is further promoted, and the orientation is further enhanced.
  • Sp B -Hb B is preferable, and it is more preferable that both R 2 and R 3 are -Sp B -Hb B.
  • a structure represented by the following formula (Z) is preferable. Equation (Z) (C p F 2p + 1 )-(CH 2 ) q -O- (CH 2 ) r -O- *
  • p is preferably 4 to 30, more preferably 4 to 20, and even more preferably 4 to 10.
  • q is preferably 0 to 5, more preferably 0 to 4, and even more preferably 0 to 3.
  • r is preferably 1 to 5, more preferably 1 to 4, and even more preferably 1 to 3.
  • R 5 is preferably a hydrogen atom, a methyl group, an ethyl group, or an aromatic group.
  • the aromatic group is not particularly limited, but is preferably 6 to 14 carbon atoms, more preferably 6 to 10 carbon atoms, and even more preferably a phenyl group.
  • R 5 is preferably a methyl group, an ethyl group, or an aromatic group, and an ethyl group is preferable, because the decomposition rate of the compound represented by the formula (X) by exposure is accelerated and the hydrophilicity is further promoted.
  • an aromatic group is more preferable, and an aromatic group is even more preferable.
  • the compound represented by the above formula (X) may have a molecular structure having symmetry or may not have symmetry.
  • the symmetry here means any of point symmetry, line symmetry, and rotational symmetry, and asymmetry does not correspond to any of point symmetry, line symmetry, and rotational symmetry. Means things.
  • the content of the specific photosensitive compound in the composition layer can be appropriately set according to the characteristics (for example, retardation and wavelength dispersion) of the optically anisotropic layer to be formed.
  • the content of the specific photosensitive compound is preferably 0.01 to 10% by mass with respect to the total mass of the liquid crystal compound in that an optically anisotropic layer having a predetermined structure is more easily formed. More preferably, it is 05 to 5% by mass.
  • a composition layer containing the above-mentioned components is formed, but the procedure is not particularly limited.
  • a method of applying a composition containing the above-mentioned specific photosensitive compound and a liquid crystal compound having a polymerizable group onto a substrate and subjecting it to a drying treatment as necessary hereinafter, also simply referred to as “coating method”.
  • a method of separately forming a composition layer and transferring it onto a substrate can be mentioned.
  • the coating method is preferable from the viewpoint of productivity.
  • the coating method will be described in detail.
  • the composition used in the coating method includes the above-mentioned specific photosensitive compound, a liquid crystal compound having a polymerizable group, and other components used as necessary (for example, a polymerization initiator, a polymerizable monomer, and a surfactant). Activators, polymers, etc.) are included.
  • the content of each component in the composition is preferably adjusted to be the content of each component in the composition layer described above.
  • the coating method is not particularly limited, and examples thereof include a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die coating method. If necessary, after the composition is applied, a treatment for drying the coating film applied on the substrate may be carried out. By carrying out the drying treatment, the solvent can be removed from the coating film.
  • the film thickness of the coating film is not particularly limited, but is preferably 0.1 to 20 ⁇ m, more preferably 0.2 to 15 ⁇ m, and even more preferably 0.5 to 10 ⁇ m.
  • Step 2C is a step of heat-treating the composition layer to orient the liquid crystal compound in the composition layer.
  • the liquid crystal compound in the composition layer is in a predetermined orientation state.
  • the liquid crystal compound is homogenically oriented in the composition.
  • the heat treatment conditions the optimum conditions are selected according to the liquid crystal compound used. Among them, the heating temperature is often 25 to 250 ° C, more often 40 to 150 ° C, and even more often 50 to 130 ° C.
  • the heating time is often 0.1 to 60 minutes, and more often 0.2 to 5 minutes.
  • Step 3C is a step of irradiating the composition layer with light for 50 seconds or less and 300 mJ / cm 2 or less under the condition of an oxygen concentration of 1% by volume or more after the step 2C.
  • the mechanism of this process will be described with reference to the drawings.
  • the composition layer contains a compound that becomes hydrophilic by light irradiation will be described as an example.
  • the liquid crystal compound LC is homogenically oriented. As shown in FIG.
  • step 3C under the condition that the oxygen concentration is 1% by volume or more, light is irradiated from the direction opposite to the composition layer 320 side of the substrate 10 (the direction of the white arrow in FIG. 11). I do. Although the light irradiation is carried out from the substrate 10 side in FIG. 11, it may be carried out from the composition layer 320 side. At that time, when the lower region 320A on the substrate 10 side of the composition layer 320 and the upper region 320B on the opposite side to the substrate 10 side are compared, the surface of the upper region 320B is on the air side, so that the upper region 320B The oxygen concentration in the lower region 320A is high, and the oxygen concentration in the lower region 320A is low.
  • the composition layer 320 when the composition layer 320 is irradiated with light, the polymerization of the liquid crystal compound easily proceeds in the lower region 320A, and the orientation state of the liquid crystal compound is fixed.
  • the specific photosensitive compound is also present in the lower region 320A, and the specific photosensitive compound is also exposed to light, and hydrophilicization progresses.
  • the alignment state of the liquid crystal compound is fixed in the lower region 320A, even if the step 4C in which the light-irradiated composition layer is heat-treated, which will be described later, the orientation state of the liquid crystal compound remains. No change occurs.
  • step 4C described later the orientation state of the liquid crystal compound changes due to the influence of the changed polarity. That is, by carrying out step 3C, the fixation of the orientation state of the liquid crystal compound is likely to proceed in the substrate-side region (lower region) of the composition layer. Further, in the region opposite to the substrate side (upper region) of the composition layer, it is difficult to fix the orientation state of the liquid crystal compound, and the polarity is changed according to the exposed specific photosensitive compound. Become.
  • step 3C oxygen concentration, irradiation time, irradiation amount, etc.
  • oxygen concentration, irradiation time, irradiation amount, etc. are the same as the various conditions of light irradiation in step 3A described above.
  • Step 4C is a step of subjecting the composition layer to a heat treatment at a temperature higher than that at the time of light irradiation after the step 3C.
  • the orientation state of the liquid crystal compound changes in the region where the polarity is changed by the specific photosensitive compound in the composition layer irradiated with light.
  • the composition layer after step 3C is heat-treated at a temperature higher than that at the time of irradiation to orient the liquid crystal compound in the composition layer not fixed in step 3C. It is a process to make it.
  • the mechanism of this process will be described with reference to the drawings.
  • step 3C when step 3C is carried out on the composition layer 320 shown in FIG. 11, the orientation state of the liquid crystal compound is fixed in the lower region 320A, whereas the orientation state of the liquid crystal compound is fixed in the upper region 320B.
  • the polymerization is difficult to proceed, and the orientation of the liquid crystal compound is not fixed.
  • the specific photosensitive compound is exposed to light and becomes hydrophilic.
  • the orientation direction of the liquid crystal compound is affected in the upper region 320B as compared with the state before light irradiation. This point will be described in more detail.
  • the composition layer contains a specific photosensitive compound that becomes hydrophilic by light irradiation
  • the composition layer contains a specific photosensitive compound that is hydrophilized by light irradiation
  • step 4C when step 4C is carried out, the liquid crystal compound is vertically oriented (homeotropic orientation) in the upper region 320B.
  • the specific photosensitive compound when the specific photosensitive compound is present near the surface of the composition layer, the liquid crystal compound tends to be vertically oriented.
  • step 3C the polymerization of the liquid crystal compound proceeds during step 3C and the orientation state of the liquid crystal compound is fixed, so that the reorientation of the liquid crystal compound occurs. Does not progress.
  • step 4C a region containing a liquid crystal compound whose orientation direction is inclined or perpendicular to the layer surface is formed.
  • the present invention is not limited to this embodiment.
  • the liquid crystal compound may be inclined or oriented.
  • the heat treatment is carried out at a temperature higher than that at the time of light irradiation.
  • the difference between the temperature of the heat treatment and the temperature at the time of light irradiation is preferably 5 ° C. or higher, more preferably 10 to 110 ° C., and even more preferably 20 to 110 ° C.
  • the temperature of the heat treatment is higher than the temperature at the time of light irradiation, and is preferably a temperature at which the non-fixed liquid crystal compound in the composition layer is oriented, and more specifically, it is often 40 to 250 ° C. More often, the temperature is 50 to 150 ° C., more often, the temperature is more than 50 ° C. and 150 ° C. or lower, and 60 to 130 ° C. is particularly common.
  • the heating time is often 0.01 to 60 minutes, and more often 0.03 to 5 minutes.
  • Step 5C is a step of subjecting the composition layer to a curing treatment after step 4C to form an optically anisotropic layer having a plurality of regions having different orientation states of the liquid crystal compounds along the thickness direction.
  • the orientation state of the liquid crystal compound in the composition layer is fixed, and as a result, a predetermined optically anisotropic layer is formed.
  • an optically anisotropic layer having a plurality of regions having different inclination angles in the orientation direction of the liquid crystal compound with respect to the layer surface is formed along the thickness direction.
  • An optically anisotropic layer having a region having a fixed orientation state can be formed.
  • Examples of the curing treatment method in step 5C include the curing treatment method in step 5A.
  • the thickness of the optically anisotropic layer is not particularly limited, but is preferably 0.05 to 10 ⁇ m, more preferably 0.1 to 8.0 ⁇ m, and even more preferably 0.2 to 6.0 ⁇ m.
  • the optical characteristics in the optically anisotropic layer in the third embodiment are not particularly limited, and the optimum value is selected according to the application.
  • a first region in which the orientation state of the homeotropically oriented liquid crystal compound is fixed and a second region in which the orientation state of the anisotropically oriented liquid crystal compound is fixed, which are produced by the above procedure, are defined.
  • the case of the optically anisotropic layer having along the thickness direction will be described in detail.
  • the optically anisotropic layer is suitable for a circular polarizing plate.
  • the first region preferably satisfies the following formula (1C-1) in that it can be applied and that light leakage in an oblique direction can be reduced when it is applied as an optical compensation plate of a liquid crystal display device. Equation (1C-1) 0 nm ⁇ ⁇ n 1d1 ⁇ 30 nm Above all, it is more preferable to satisfy the formula (1C-2).
  • Equation (1C-2) 0 nm ⁇ ⁇ n 1d1 ⁇ 20 nm
  • the retardation in the thickness direction at a wavelength of 550 nm in the first region of the optically anisotropic layer is preferably ⁇ 150 to ⁇ 20 nm, more preferably ⁇ 120 to ⁇ 20 nm.
  • the optically anisotropic layer is a circular polarizing plate. It is preferable that the second region satisfies the following formula (2C-1) in that it can be suitably applied and that it can be suitably applied to the optical compensation plate of the liquid crystal display device. That is, the in-plane retardation at a wavelength of 550 nm in the second region is preferably 100 to 180 nm.
  • Equation (2C-1) 100 nm ⁇ ⁇ n 2d2 ⁇ 180 nm Above all, it is more preferable to satisfy the formula (2C-2).
  • Equation (2C-2) 110 nm ⁇ ⁇ n 2d2 ⁇ 170 nm
  • the refractive index anisotropy ⁇ n2 means the refractive index anisotropy in the first region.
  • the optically anisotropic layer in the third embodiment preferably exhibits reverse wavelength dispersibility. That is, Re (450), which is an in-plane retardation measured at a wavelength of 450 nm of the optically anisotropic layer, and Re (550), which is an in-plane retardation measured at a wavelength of 550 nm of the optically anisotropic layer, are optically anisotropic. It is preferable that Re (650), which is the in-plane retardation measured at a wavelength of 650 nm of the layer, has a relationship of Re (450) ⁇ Re (550) ⁇ Re (650).
  • the optical characteristics of the optically anisotropic layer in the third embodiment are not particularly limited, but it is preferable that the optical anisotropic layer functions as a ⁇ / 4 plate or as an optical compensation plate of a liquid crystal display device.
  • the ⁇ / 4 plate is a plate having a function of converting linearly polarized light of a specific wavelength into circularly polarized light (or converting circularly polarized light into linearly polarized light), and the in-plane retardation Re ( ⁇ ) at a specific wavelength of ⁇ nm is Re.
  • a plate (optically anisotropic layer) that satisfies ( ⁇ ) ⁇ / 4.
  • This equation may be achieved at any wavelength in the visible light region (eg, 550 nm), but the in-plane retardation Re (550) at a wavelength of 550 nm satisfies the relationship of 100 nm ⁇ Re (550) ⁇ 180 nm. Is preferable.
  • the fourth embodiment of the method for producing an optically anisotropic layer of the present invention comprises the following steps 1D to 5D.
  • the region in which the oriented state in which the liquid crystal compound is oriented (for example, the horizontally oriented state) is fixed and the state in which the liquid crystal compound is not oriented (isotropic of the liquid crystal compound)
  • An optically anisotropic layer having a region formed by fixing the phase) along the thickness direction is formed.
  • Step 1D Forming a composition layer containing a liquid crystal compound having a polymerizable group
  • Step 2D A process of heat-treating the composition layer to orient the liquid crystal compound in the composition layer
  • Step 3D After step 2D
  • Step 4D After step 3D, the composition layer is irradiated with light for 50 seconds or less and 300 mJ / cm 2 or less under the condition of an oxygen concentration of 1% by volume or more.
  • the heat treatment is performed at a temperature higher than that at the time of light irradiation and at a temperature at which the liquid crystal compound becomes an isotropic phase or higher.
  • Step of forming an optically anisotropic layer having a plurality of different regions along the thickness direction The procedure of each of the above steps will be described in detail below.
  • Step 1D is a step of forming a composition layer containing a liquid crystal compound having a polymerizable group. By carrying out this step, a composition layer to be subjected to a light irradiation treatment described later is formed.
  • the liquid crystal compound contained in the composition layer is as described in step 1A. Further, as described in the above-mentioned step 1A, the composition layer may contain other components other than the liquid crystal compound.
  • a composition layer containing the above-mentioned components is formed, but the procedure is not particularly limited.
  • a method of applying the above-mentioned composition containing a liquid crystal compound having a polymerizable group onto a substrate and subjecting it to a drying treatment as necessary hereinafter, also simply referred to as “coating method”
  • coating method examples thereof include a method of forming a layer and transferring it onto a substrate.
  • the coating method is preferable from the viewpoint of productivity.
  • the coating method will be described in detail.
  • the composition used in the coating method includes the above-mentioned liquid crystal compounds having a polymerizable group, and other components used as necessary (for example, a polymerization initiator, a polymerizable monomer, a surfactant, and the like. , Polymers, etc.) are included.
  • the content of each component in the composition is preferably adjusted to be the content of each component in the composition layer described above.
  • the coating method is not particularly limited, and examples thereof include a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die coating method. If necessary, after the composition is applied, a treatment for drying the coating film applied on the substrate may be carried out. By carrying out the drying treatment, the solvent can be removed from the coating film.
  • the film thickness of the coating film is not particularly limited, but is preferably 0.1 to 20 ⁇ m, more preferably 0.2 to 15 ⁇ m, and even more preferably 0.5 to 10 ⁇ m.
  • Step 2D is a step of heat-treating the composition layer to orient the liquid crystal compound in the composition layer.
  • the liquid crystal compound in the composition layer is in a predetermined orientation state.
  • the liquid crystal compound is homogenically oriented in the composition.
  • the heat treatment conditions the optimum conditions are selected according to the liquid crystal compound used. Among them, the heating temperature is often 25 to 250 ° C, more often 40 to 150 ° C, and even more often 50 to 130 ° C.
  • the heating time is often 0.1 to 60 minutes, and more often 0.2 to 5 minutes.
  • Step 3D is a step of irradiating the composition layer with light for 50 seconds or less and 300 mJ / cm 2 or less under the condition of an oxygen concentration of 1% by volume or more after the step 2D.
  • the mechanism of this process will be described with reference to the drawings.
  • the liquid crystal compound LC is homogenically oriented in the composition layer.
  • step 3D under the condition that the oxygen concentration is 1% by volume or more, light is irradiated from the direction opposite to the composition layer 420 side of the substrate 10 (the direction of the white arrow in FIG. 13). I do. Although the light irradiation is carried out from the substrate 10 side in FIG.
  • the composition layer 420 may be carried out from the composition layer 420 side.
  • the surface of the upper region 420B is on the air side, so that the upper region 420B
  • the oxygen concentration in the lower region 420A is high, and the oxygen concentration in the lower region 420A is low. Therefore, when the composition layer 420 is irradiated with light, the polymerization of the liquid crystal compound easily proceeds in the lower region 420A, and the orientation state of the liquid crystal compound is fixed.
  • the orientation state of the liquid crystal compound does not change.
  • the oxygen concentration is high in the upper region 420B, even if light irradiation is performed, the polymerization of the liquid crystal compound is inhibited by the oxygen, and the polymerization is difficult to proceed. Therefore, when the step 4D described later is carried out, the orientation state of the liquid crystal compound changes. That is, by carrying out the step 3D, the fixation of the orientation state of the liquid crystal compound is likely to proceed in the substrate-side region (lower region) of the composition layer. Further, in the region opposite to the substrate side (upper region) of the composition layer, it is difficult to fix the orientation state of the liquid crystal compound, and the orientation state of the liquid crystal compound is changed by the step 4D described later.
  • step 3D oxygen concentration, irradiation time, irradiation amount, etc.
  • oxygen concentration, irradiation time, irradiation amount, etc. are the same as the various conditions of light irradiation in step 3A described above.
  • the step 4D is a step of subjecting the composition layer to a heat treatment after the step 3D at a temperature higher than that at the time of light irradiation and at a temperature higher than the temperature at which the liquid crystal compound becomes an isotropic phase.
  • the liquid crystal compound exhibits an isotropic phase in the upper region where the orientation state of the liquid crystal compound in the composition layer is not fixed.
  • step 3D when step 3D is performed on the composition layer 420 shown in FIG. 13, the orientation state of the liquid crystal compound is fixed in the lower region 420A, whereas the orientation state of the liquid crystal compound is fixed in the upper region 420B.
  • the polymerization is difficult to proceed, and the orientation of the liquid crystal compound is not fixed. Therefore, when step 4D is carried out, as shown in FIG. 14, since the polymerization of the liquid crystal compound has not progressed in the upper region 420B, the orientation state of the liquid crystal compound is broken and the phase becomes isotropic.
  • the polymerization of the liquid crystal compound proceeds during the step 3D and the orientation state of the liquid crystal compound is fixed, so that the reorientation of the liquid crystal compound occurs. Does not progress.
  • step 4D a region in which the alignment state (for example, the horizontal alignment state) of the liquid crystal compound is fixed along the thickness direction and a state in which the liquid crystal compound is not oriented (liquid crystal compound).
  • An optically anisotropic layer having a region formed by fixing the isotropic phase of the above is formed.
  • the heat treatment is carried out at a temperature higher than the temperature at the time of light irradiation and at a temperature higher than the temperature at which the liquid crystal compound becomes an isotropic phase.
  • the difference between the temperature of the heat treatment and the temperature at the time of light irradiation is preferably 5 ° C. or higher, more preferably 10 to 110 ° C., and even more preferably 20 to 110 ° C.
  • the temperature of the heat treatment is preferably higher than the temperature at the time of light irradiation, and is preferably a temperature in which the non-fixed liquid crystal compound in the composition layer is an isotropic phase, and more specifically, in the case of 40 to 250 ° C.
  • the temperature is 50 to 150 ° C., more often, more than 50 ° C. and 150 ° C. or lower, and 60 to 130 ° C. is particularly common.
  • the heating time is often 0.01 to 60 minutes, and more often 0.03 to 5 minutes.
  • Step 5D is a step of subjecting the composition layer to a curing treatment after step 4D to form an optically anisotropic layer having a plurality of regions having different orientation states of the liquid crystal compounds along the thickness direction.
  • the orientation state of the liquid crystal compound in the composition layer is fixed, and as a result, a predetermined optically anisotropic layer is formed.
  • Examples of the curing treatment method in step 5D include the curing treatment method in step 5A.
  • the thickness of the optically anisotropic layer is not particularly limited, but is preferably 0.05 to 10 ⁇ m, more preferably 0.1 to 8.0 ⁇ m, and even more preferably 0.2 to 6.0 ⁇ m.
  • a region in which the orientation state of the horizontally oriented liquid crystal compound is fixed and a region in which the liquid crystal compound exhibits an isotropic phase are fixed along the thickness direction.
  • the embodiment of the optically anisotropic layer having the above is described, the present invention is not limited to this embodiment as long as the liquid crystal compound contains a region in which the state of exhibiting an isotropic phase is fixed.
  • the orientation state of the liquid crystal compound is, for example, nematic orientation (state in which a nematic phase is formed) or smectic orientation (formation of a smectic phase).
  • orientation state examples include nematic orientation, columnar orientation (a state in which a columnar phase is formed), and cholesteric orientation. More specifically, an optical difference having a region in which the orientation state of the liquid crystal compound vertically oriented is fixed along the thickness direction and a region in which the state in which the liquid crystal compound exhibits an isotropic phase is fixed. A square layer may be formed.
  • an optically anisotropic layer having a region formed by fixing a cholesteric liquid crystal phase formed by using a liquid crystal compound and a region formed by fixing a state in which the liquid crystal compound exhibits an isotropic phase along the thickness direction. May be formed.
  • the optical characteristics of the optically anisotropic layer in the fourth embodiment are not particularly limited, but it is preferable that the optical anisotropic layer functions as a ⁇ / 4 plate.
  • the ⁇ / 4 plate is a plate having a function of converting linearly polarized light of a specific wavelength into circularly polarized light (or converting circularly polarized light into linearly polarized light), and the in-plane retardation Re ( ⁇ ) at a specific wavelength of ⁇ nm is Re.
  • a plate (optically anisotropic layer) that satisfies ( ⁇ ) ⁇ / 4.
  • This equation may be achieved at any wavelength in the visible light region (eg, 550 nm), but the in-plane retardation Re (550) at a wavelength of 550 nm satisfies the relationship 110 nm ⁇ Re (550) ⁇ 180 nm. Is preferable.
  • the optically anisotropic layer can be combined with various members.
  • the optically anisotropic layer may be combined with another optically anisotropic layer. That is, as shown in FIG. 15, a laminate 24 including the substrate 10, the optically anisotropic layer 20 manufactured by the above-mentioned manufacturing method, and another optically anisotropic layer 22 may be manufactured.
  • the laminated body 24 shown in FIG. 15 includes the substrate 10, the laminated body may not include the substrate.
  • the other optically anisotropic layer is not particularly limited, and examples thereof include A plates (positive A plate and negative A plate) and C plates (positive C plate and negative C plate).
  • the C plate is preferable because it can be easily applied to various uses (for example, a circular polarizing plate) described later.
  • the range of the absolute value of the retardation in the thickness direction at the wavelength of 550 nm of the C plate is not particularly limited, but is preferably 5 to 300 nm, more preferably 10 to 200 nm.
  • a plate and C plate are defined as follows. There are two types of A plates, a positive A plate (positive A plate) and a negative A plate (negative A plate), and the slow axis direction in the film plane (the direction in which the refractive index in the plane is maximized). ) Is nx, the refractive index in the direction orthogonal to the slow axis in the plane is ny, and the refractive index in the thickness direction is nz, the positive A plate satisfies the relationship of the equation (A1). The negative A plate satisfies the relation of the formula (A2). The positive A plate shows a positive value for Rth, and the negative A plate shows a negative value for Rth.
  • Equation (A1) nx> ny ⁇ nz Equation (A2) ny ⁇ nx ⁇ nz
  • ⁇ includes not only the case where both are completely the same, but also the case where both are substantially the same. “Substantially the same” means, for example, “ny ⁇ nz” when (ny-nz) ⁇ d (where d is the thickness of the film) is -10 to 10 nm, preferably -5 to 5 nm. In the case where (nx-nz) ⁇ d is ⁇ 10 to 10 nm, preferably ⁇ 5 to 5 nm, it is also included in “nx ⁇ nz”.
  • C plates There are two types of C plates, a positive C plate (positive C plate) and a negative C plate (negative C plate).
  • the positive C plate satisfies the relationship of the formula (C1)
  • the negative C plate is It satisfies the relationship of the equation (C2).
  • the positive C plate shows a negative value for Rth
  • the negative C plate shows a positive value for Rth.
  • Equation (C1) nz> nx ⁇ ny Equation (C2) nz ⁇ nx ⁇ ny
  • ⁇ includes not only the case where both are completely the same, but also the case where both are substantially the same.
  • substantially the same means, for example, that (nx-ny) x d (where d is the thickness of the film) is included in "nx ⁇ ny" even when it is 0 to 10 nm, preferably 0 to 5 nm. Is done.
  • the method for producing the above-mentioned laminate is not particularly limited, and a known method can be mentioned.
  • a method of laminating an optically anisotropic layer obtained by the production method of the present invention and another optically anisotropic layer (for example, a C plate) to obtain a laminated body can be mentioned.
  • another separately prepared optically anisotropic layer may be bonded onto the optically anisotropic layer obtained by the manufacturing method of the present invention, or the optics obtained by the manufacturing method of the present invention may be bonded.
  • a composition for forming another optically anisotropic layer may be applied onto the anisotropic layer to form another optically anisotropic layer.
  • the optically anisotropic layer obtained by the production method of the present invention may be combined with a polarizing element. That is, as shown in FIG. 16, the optically anisotropic layer 28 with a splitter may be manufactured, which includes the substrate 10, the optically anisotropic layer 20 manufactured by the above-mentioned manufacturing method, and the polarizing element 26. .. In FIG. 16, the polarizing element 26 is arranged on the substrate 10, but the present invention is not limited to this, and the polarizing element 26 may be arranged on the optically anisotropic layer 20. Further, although the optically anisotropic layer 28 with a polarizing element shown in FIG. 16 includes the substrate 10, the substrate may not be included in the optically anisotropic layer with a polarizing element.
  • the positional relationship when laminating the optically anisotropic layer and the polarizing element is not particularly limited, but the optically anisotropic layer fixes the orientation state of the liquid crystal compound twist-oriented along the spiral axis extending along the thickness direction.
  • the first region formed by the The absolute value of the angle formed with is preferably 5 to 25 °, more preferably 10 to 20 °, in that the optically anisotropic layer can be suitably applied to a circular polarizing plate or the like.
  • the twist angle of the liquid crystal compound in the first region is also negative, and the twist angle of the liquid crystal compound in the first region is also negative.
  • the twist angle of the liquid crystal compound in the first region is also positive.
  • the rotation angle of the in-plane slow-phase axis is a clock with reference to the absorber absorption axis when visually recognized from the splitter side.
  • the case of rotation means the case where the angle formed by the in-plane slow-phase axis and the stator is positive, which means that the in-plane slow-phase axis is based on the absorption axis of the polarizing element when visually recognized from the splitter side. It means that the rotation angle of is counterclockwise.
  • twist angle of the liquid crystal compound it is negative and counterclockwise when the orientation direction of the liquid crystal compound on the back side is clockwise (clockwise) with respect to the orientation direction of the liquid crystal compound on the front side (front side).
  • the time of (counterclockwise) is expressed as positive.
  • the polarizing element may be any member as long as it has a function of converting natural light into specific linear polarization, and examples thereof include an absorption type polarizing element.
  • the type of the polarizing element is not particularly limited, and a commonly used polarizing element can be used. Examples thereof include an iodine-based polarizing element, a dye-based polarizing element using a dichroic dye, and a polyene-based polarizing element.
  • Iodine-based and dye-based polarizing elements are generally produced by adsorbing iodine or a dichroic dye on polyvinyl alcohol and stretching it.
  • a protective film may be arranged on one side or both sides of the polarizing element.
  • the method for producing the optically anisotropic layer with a polarizing element is not particularly limited, and a known method can be mentioned.
  • a method of laminating an optically anisotropic layer obtained by the production method of the present invention and a polarizing element to obtain an optically anisotropic layer with a polarizing element can be mentioned.
  • the above-mentioned laminate and the polarizing element may be laminated to produce a laminate with a polarizing element. good.
  • the optically anisotropic layer can be applied to various applications.
  • the optically anisotropic layer can be suitably applied to a circular polarizing plate, and the optically anisotropic layer with a polarizing element can also be used as a circular polarizing plate.
  • Circular polarizing plates having the above configuration are used for antireflection applications of image display devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), electroluminescence displays (ELDs), and cathode tube display devices (CRTs). It is preferably used and can improve the contrast ratio of the display light.
  • LCDs liquid crystal displays
  • PDPs plasma display panels
  • ELDs electroluminescence displays
  • CRTs cathode tube display devices
  • the external light is linearly polarized by the polarizing film, and then passes through the optically anisotropic layer to be circularly polarized.
  • the circularly polarized state is inverted, and when it passes through the optically anisotropic layer again, it becomes linearly polarized light tilted by 90 ° from the time of incident, reaches the polarizing film, and is absorbed.
  • the influence of external light can be suppressed.
  • the above-mentioned optically anisotropic layer with a polarizing element or the laminated body with a polarizing element is preferably applied to an organic EL display device. That is, it is preferable that the optically anisotropic layer with a polarizing element or the laminate with a polarizing element is arranged on the organic EL panel of the organic EL display device and applied to antireflection applications.
  • the organic EL panel is a member in which a plurality of organic compound thin films including a light emitting layer or a light emitting layer are formed between a pair of electrodes of an anode and a cathode, and is a hole injection layer, a hole transport layer, and an electron injection layer in addition to the light emitting layer.
  • An electron transport layer, a protective layer, and the like may be provided, and each of these layers may have other functions.
  • Various materials can be used to form each layer.
  • the optically anisotropic layer can be suitably applied to an optical compensation plate of a liquid crystal display device, and the optically anisotropic layer with a polarizing element can also be used as an optical compensation plate of a liquid crystal display device.
  • the liquid crystal cell used in the liquid crystal display device is a VA (Vertical Element) mode, an OCB (Optically Compensated Bend) mode, an IPS (In-Plane-Switching) mode, an FFS (Fringe-Field-Switching) mode, or a TN (Fringe-Field-Switching) mode.
  • VA Vertical Element
  • OCB Optically Compensated Bend
  • IPS In-Plane-Switching
  • FFS Frringe-Field-Switching
  • TN Fe-Field-Switching
  • the Twisted Nematic) mode is preferred, but is not limited to these.
  • the optically anisotropic layer with a polarizing element is used as an optical compensation plate for a liquid crystal display in IPS mode or FFS mode
  • the optically anisotropic layer is a homogenically oriented (horizontally oriented) liquid crystal as shown in FIG. It is preferable to have a region in which the orientation state of the compound is fixed and a region in which the orientation state of the homeotropic oriented (vertically oriented) liquid crystal compound is fixed. In this case, it is preferable that the angle formed by the in-plane slow phase axis of the region formed by fixing the orientation state of the homogeneously oriented (horizontally oriented) liquid crystal compound and the absorption axis of the polarizing element is orthogonal or parallel, and specifically.
  • the angle between the in-plane slow phase axis of the region where the alignment state of the homogenically oriented (horizontally oriented) liquid crystal compound is fixed and the absorption axis of the polarizing element is 0 to 5 ° or 85 to 95 °. Is more preferable.
  • the "in-plane slow phase axis" of the region in which the alignment state of the liquid crystal compound oriented in homogenius (horizontal orientation) is fixed is the region in which the orientation state of the liquid crystal compound in homogenius orientation (horizontal orientation) is fixed. It means the direction in which the refractive index is maximum in the plane, and the "absorption axis" of the substituent means the direction in which the absorbance is highest.
  • the orientation state of the polarizing element and the homeotropic oriented (vertically oriented) liquid crystal compound is fixed.
  • a region a region formed by fixing the orientation state of the liquid crystal compound homogenically oriented (horizontally oriented), and an orientation state of the liquid crystal compound arranged in the order of the liquid crystal cell, or a substituent and a homogenius oriented (horizontally oriented) liquid crystal compound. It is preferable that the region is fixed, the region formed by fixing the orientation state of the homeotropic oriented (vertically oriented) liquid crystal compound, and the liquid crystal cell are arranged in this order.
  • Example 1> Preparation of Cellulose Achillate Film (Substrate)
  • the following composition was put into a mixing tank, stirred, and further heated at 90 ° C. for 10 minutes. Then, the obtained composition was filtered through a filter paper having an average pore diameter of 34 ⁇ m and a sintered metal filter having an average pore diameter of 10 ⁇ m to prepare a dope.
  • the solid content concentration of the dope is 23.5% by mass
  • the amount of the plasticizer added is the ratio to the cellulose acylate
  • Cellulose acylate dope ⁇ Cellulose acylate (acetyl substitution degree 2.86, viscosity average polymerization degree 310) 100 parts by mass sugar ester compound 1 (represented by chemical formula (S4)) 6.0 parts by mass sugar ester compound 2 (represented by chemical formula (S5)) 2.0 parts by mass silica particle dispersion (AEROSIL R972, Nippon Aerosil Co., Ltd.) Made) 0.1 part by mass solvent (methylene chloride / methanol / butanol) ⁇
  • the dope prepared above was cast using a drum film forming machine.
  • the dope was cast from the die so that it was in contact with the metal support cooled to 0 ° C., and then the resulting web (film) was stripped.
  • the drum was made of SUS.
  • the web (film) obtained by casting from the drum After peeling the web (film) obtained by casting from the drum, it is dried in the tenter device for 20 minutes using a tenter device that clips and conveys both ends of the web at 30 to 40 ° C. during film transfer. did. Subsequently, the web was rolled and then dried by zone heating. The resulting web was knurled and then rolled up.
  • the film thickness of the obtained cellulose acylate film was 40 ⁇ m
  • the in-plane retardation Re (550) at a wavelength of 550 nm was 1 nm
  • the thickness direction retardation Rth (550) at a wavelength of 550 nm was 26 nm.
  • the cellulose acylate film produced above was continuously subjected to a rubbing treatment.
  • the longitudinal direction of the long film and the conveying direction were parallel, and the angle between the longitudinal direction of the film (transporting direction) and the rotation axis of the rubbing roller was set to 80 °.
  • the longitudinal direction (conveyance direction) of the film is 90 ° and the clockwise direction is expressed as a positive value with respect to the film width hand direction (0 °) when observed from the film side
  • the rotation axis of the rubbing roller is 10 °. be.
  • the position of the rotation axis of the rubbing roller is a position rotated by 80 ° counterclockwise with respect to the longitudinal direction of the film.
  • a composition for forming an optically anisotropic layer (1) containing a rod-shaped liquid crystal compound having the following composition is applied using a Gieser coating machine to compose the composition.
  • a material layer was formed (corresponding to step 1A).
  • the absolute value of the weighted average spiral inducing force of the chiral agent in the composition layer in step 1A was 0.0 ⁇ m -1 .
  • the obtained composition layer was heated at 80 ° C. for 60 seconds (corresponding to step 2A). By this heating, the rod-shaped liquid crystal compound of the composition layer was oriented in a predetermined direction.
  • the composition layer was irradiated with ultraviolet rays for 5 seconds using a 365 nm LED lamp (manufactured by Acroedge Co., Ltd.) at 40 ° C. under oxygen-containing air (oxygen concentration: about 20% by volume) (irradiation amount:). 13 mJ / cm 2 ) (corresponding to step 3A). Subsequently, the obtained composition layer was heated at 80 ° C. for 10 seconds (corresponding to step 4A). After that, nitrogen purging was performed to irradiate the composition layer with ultraviolet rays using a metal halide lamp (manufactured by Eye Graphics Co., Ltd.) at 80 ° C.
  • a metal halide lamp manufactured by Eye Graphics Co., Ltd.
  • the molar extinction coefficient of the left-handed twist chiral agent (L1) at 365 nm in the composition for forming an optically anisotropic layer (1) is 40 L / (mol ⁇ cm), and the HTP of this chiral agent is light of 365 nm. Even after irradiation (13 mJ / cm 2 ), there was no change compared to before irradiation.
  • the molar extinction coefficient of the right-handed chiral agent (R1) at 365 nm is 38,450 L / (mol ⁇ cm), and the HTP of this chiral agent is compared with that before irradiation when irradiated with light of 365 nm (13 mJ / cm 2 ). It decreased by 35 ⁇ m -1 .
  • the molar extinction coefficient of the photopolymerization initiator (Irgacure819) at 365 nm was 860 L / (mol ⁇ cm).
  • Rod-shaped liquid crystal compound (A) (hereinafter, a mixture of compounds)
  • Polymer (A) (In the formula, the numerical value described in each repeating unit represents the content (mass%) of each repeating unit with respect to all repeating units).
  • Polymer (B) (In the formula, the numerical value described in each repeating unit represents the content (mass%) of each repeating unit with respect to all repeating units).
  • the optical film (F-1) produced above was cut in parallel with the rubbing direction, and the optically anisotropic layer was observed from the cross-sectional direction with a polarizing microscope.
  • the thickness of the optically anisotropic layer is 2.7 ⁇ m
  • the region (second region) of the thickness (d2) of 1.3 ⁇ m on the substrate side of the optically anisotropic layer is a homogeneous orientation without a twist angle, and is optically anisotropic.
  • the liquid crystal compound was twist-oriented in the region (first region) having a thickness (d1) of 1.4 ⁇ m on the air side (opposite side of the substrate) of the sex layer.
  • the optical characteristics of the optical film (F-1) were determined using Axoscan of Axometrics and analysis software (Multi-Layer Analysis) of the same company.
  • the product ( ⁇ n2d1) of ⁇ n2 and the thickness d2 at a wavelength of 550 nm in the second region is 173 nm
  • the twist angle of the liquid crystal compound is 0 °
  • the orientation axis angle of the liquid crystal compound with respect to the longitudinal direction of the film is ⁇ 10 on the side in contact with the substrate. °
  • the side in contact with the first region was -10 °.
  • the product ( ⁇ n1d1) of ⁇ n1 and the thickness d1 at a wavelength of 550 nm in the first region is 184 nm
  • the twist angle of the liquid crystal compound is 75 °
  • the orientation axis angle of the liquid crystal compound with respect to the longitudinal direction of the film is in the second region.
  • the contact side was ⁇ 10 ° and the air side was ⁇ 85 °.
  • the orientation axis angle of the liquid crystal compound contained in the optically anisotropic layer is 0 ° with respect to the longitudinal direction of the film, and the film is observed from the surface side of the optically anisotropic layer in a clockwise direction (clockwise). Time is shown as negative, and counterclockwise (counterclockwise) is shown as positive.
  • the substrate is observed from the surface side of the optically anisotropic layer, and the liquid crystal on the substrate side (back side) is based on the orientation direction of the liquid crystal compound on the surface side (front side).
  • the orientation direction of the compound is clockwise (clockwise), it is expressed as negative, and when it is counterclockwise (counterclockwise), it is expressed as positive.
  • a polyvinyl alcohol (PVA) film having a thickness of 80 ⁇ m was immersed in an iodine aqueous solution having an iodine concentration of 0.05% by mass at 30 ° C. for 60 seconds for staining.
  • the obtained film was longitudinally stretched to 5 times the original length while immersed in a boric acid aqueous solution having a boric acid concentration of 4% by mass for 60 seconds, and then dried at 50 ° C. for 4 minutes.
  • a polarizing element having a thickness of 20 ⁇ m was obtained.
  • a commercially available cellulose acylate film Fujitac TG40UL (manufactured by FUJIFILM Corporation) is prepared, immersed in a sodium hydroxide aqueous solution at 55 ° C. at 1.5 mol / liter, and then sufficiently sodium hydroxide is added with water. Rinse off. Then, the film obtained in a dilute aqueous sulfuric acid solution at 0.005 mol / liter at 35 ° C. was immersed for 1 minute, and then immersed in water to thoroughly wash away the dilute aqueous sulfuric acid solution. Finally, the obtained film was sufficiently dried at 120 ° C. to prepare a polarizing element protective film whose surface was saponified.
  • the above-mentioned optical film (F-1) is saponified, and the above-mentioned polarizing element and the above-mentioned polarization are applied to the substrate surface contained in the optical film (F-1).
  • the child protective film was continuously bonded using a polyvinyl alcohol-based adhesive to prepare a long circular polarizing plate (P-1). That is, the circularly polarizing plate (P-1) had a polarizing element protective film, a polarizing element, a substrate, and an optically anisotropic layer in this order.
  • the absorption axis of the polarizing element coincides with the longitudinal direction of the circular polarizing plate, and the rotation angle of the in-plane slow phase axis of the second region with respect to the absorption axis of the polarizing element is 10 ° with respect to the absorption axis of the substituent.
  • the rotation angle of the in-plane retarding axis on the surface of the surface opposite to the second region side of the first region was 85 °.
  • the rotation angle of the in-plane slow-phase axis is set to 0 ° with respect to the longitudinal direction of the circularly polarizing plate by observing the optically anisotropic layer from the substituent side, and is positive and clockwise in the counterclockwise direction. It is represented by a negative angle value.
  • Example 2 (Alkaline saponification treatment) After passing the above-mentioned cellulose acylate film through a dielectric heating roll having a temperature of 60 ° C. and raising the film surface temperature to 40 ° C., an alkaline solution having the composition shown below is applied to the band surface of the film using a bar coater. The film was applied at a coating amount of 14 ml / m 2 and conveyed under a steam-type far-infrared heater manufactured by Noritake Co., Ltd. Limited, which was heated to 110 ° C. for 10 seconds. Subsequently, 3 ml / m 2 of pure water was subsequently applied using a bar coater.
  • the film was transported to a drying zone at 70 ° C. for 10 seconds and dried to prepare a cellulose acylate film treated with alkali saponification.
  • the alignment film coating solution having the following composition was continuously applied to the surface of the cellulose acylate film subjected to the alkali saponification treatment with a # 14 wire bar. It was dried with warm air at 60 ° C. for 60 seconds and further with warm air at 100 ° C. for 120 seconds.
  • Alignment film coating liquid ⁇ 28 parts by mass of modified polyvinyl alcohol shown below Citric acid ester (AS3, manufactured by Sankyo Chemical Co., Ltd.) 1.2 parts by mass Photopolymerization initiator (Irgacure2959, manufactured by BASF) 0.84 parts by mass Glutaraldehyde 2.8 parts by mass 699 parts by mass of water 226 parts by mass of methanol ⁇
  • the alignment film prepared above was continuously subjected to a rubbing treatment.
  • the longitudinal direction of the long film and the conveying direction are parallel, and the angle between the longitudinal direction of the film (transporting direction) and the rotation axis of the rubbing roller is 45 °.
  • the longitudinal direction (conveyance direction) of the film is 90 ° and the clockwise direction is expressed as a positive value with respect to the film width hand direction (0 °) when observed from the film side
  • the rotation axis of the rubbing roller is 135 °. be.
  • the position of the rotation axis of the rubbing roller is a position rotated by 45 ° counterclockwise with respect to the longitudinal direction of the film.
  • the composition (2) for forming an optically anisotropic layer containing a rod-shaped liquid crystal compound having the following composition is applied using a Gieser coating machine to obtain a composition.
  • a layer was formed (corresponding to step 1C).
  • the obtained composition layer was heated at 120 ° C. for 80 seconds (corresponding to step 2C).
  • the rod-shaped liquid crystal compound of the composition layer was oriented in a predetermined direction.
  • the composition layer was irradiated with ultraviolet rays for 5 seconds using a 365 nm LED lamp (manufactured by Acroedge Co., Ltd.) at 40 ° C.
  • composition for forming an optically anisotropic layer (2) ⁇ 20 parts by mass of the above rod-shaped liquid crystal compound (A) 40 parts by mass of the following rod-shaped liquid crystal compound (D) 40 parts by mass of the following rod-shaped liquid crystal compound (E) 40 parts by mass of ethylene oxide-modified trimethyla propantriacrylate (V # 360, Osaka Organic Chemistry) Co., Ltd.) 4 parts by mass Photopolymerization initiator (Irgacure819, manufactured by BASF) 3 parts by mass The above polymer (A) 0.08 parts by mass The following photosensitive compound (A) 0.4 parts by mass The following ionic compound (A) 3.0 parts by mass Methyl ethyl ketone 156 parts by mass ⁇
  • the photosensitive compound (A) in the composition for forming an optically anisotropic layer (2) is a decomposition product (A) having a hydrophilic carboxyl group when irradiated with light of 365 nm (30 mJ / cm 2 ). Arose.
  • the optical film (F-2) produced above was cut in parallel with the rubbing direction, and the optically anisotropic layer was observed from the cross-sectional direction with a polarizing microscope.
  • the thickness of the optically anisotropic layer is 4.3 ⁇ m
  • the region (second region) having a thickness of 3.0 ⁇ m on the substrate side of the optically anisotropic layer is homogeneously oriented
  • the air side (substrate) of the optically anisotropic layer is
  • the liquid crystal compound was homeotropically oriented in the region (first region) having a thickness of 1.3 ⁇ m (on the opposite side).
  • the optical characteristics of the optical film (F-2) were determined using Axoscan of Axometrics and analysis software (Multi-Layer Analysis) of the same company.
  • the in-plane retardation ( ⁇ n2d2) at a wavelength of 550 nm in the second region was 140 nm, and the angle of the in-plane slow phase axis with respect to the longitudinal direction of the film was ⁇ 45 °.
  • the in-plane retardation ( ⁇ n1d1) at a wavelength of 550 nm in the first region was 0 nm, and the retardation in the thickness direction at a wavelength of 550 nm in the first region was ⁇ 60 nm.
  • the angle of the in-plane slow-phase axis is 0 ° with respect to the longitudinal direction of the film, and the substrate is observed from the surface side of the optically anisotropic layer. Clockwise (clockwise) is negative and counterclockwise. The time of (counterclockwise) is expressed as positive.
  • Example 2 (Making a circular polarizing plate)
  • the optical film (F-2) produced above is sacrificed, and the above-mentioned polarizing element and the above-mentioned polarizing element protection film are polyvinyl-coated on the substrate surface contained in the optical film (F-2).
  • a long circular polarizing plate (P-2) was prepared by continuously laminating them using an alcohol-based adhesive. That is, the circularly polarizing plate (P-2) had a polarizing element protective film, a polarizing element, a substrate, and an optically anisotropic layer in this order.
  • the absorption axis of the polarizing element coincided with the longitudinal direction of the circular polarizing plate, and the rotation angle of the in-plane slow-phase axis of the second region with respect to the absorption axis of the polarizing element was 45 °.
  • the rotation angle of the in-plane slow-phase axis is set to 0 ° with respect to the longitudinal direction of the circularly polarizing plate by observing the optically anisotropic layer from the substituent side, and is positive and clockwise in the counterclockwise direction. It is represented by a negative angle value.
  • Example 3 (Formation of optically anisotropic layer)
  • the cellulose acylate film produced in Example 1 was continuously subjected to a rubbing treatment.
  • the longitudinal direction of the long film and the conveying direction were parallel, and the angle between the longitudinal direction of the film (transporting direction) and the rotation axis of the rubbing roller was 45 °.
  • the longitudinal direction (conveyance direction) of the film is 90 ° and the counterclockwise direction is represented by a positive value with respect to the width direction of the cellulose acylate film as a reference (0 °) when observed from the cellulose acylate film side
  • the axis of rotation of the rubbing roller was 135 °.
  • the position of the rotation axis of the rubbing roller was a position rotated 45 ° clockwise with respect to the longitudinal direction of the cellulose acylate film.
  • the composition for forming an optically anisotropic layer (3) containing a rod-shaped liquid crystal compound having the following composition is applied using a Gieser coating machine to form a composition layer.
  • the obtained composition layer was heated at 80 ° C. for 60 seconds (corresponding to step 2D).
  • the rod-shaped liquid crystal compound of the composition layer was oriented in a predetermined direction.
  • the composition layer was irradiated with ultraviolet rays for 5 seconds using a 365 nm LED lamp (manufactured by Acroedge Co., Ltd.) at 40 ° C.
  • the molar extinction coefficient of the photopolymerization initiator (Irgacure907) at 365 nm was 140 L / (mol ⁇ cm).
  • composition for forming an optically anisotropic layer (3) ⁇ 80 parts by mass of the above-mentioned rod-shaped liquid crystal compound (A) 10 parts by mass of the above-mentioned polymerizable compound (C) 10 parts by mass of the above polymerizable compound (C) 10 parts by mass of ethylene oxide-modified trimethyl propanetriacrylate (V # 360, Osaka Organic Chemistry) (Manufactured by Co., Ltd.) 4 parts by mass Photopolymerization initiator (Irgacure907, manufactured by BASF) 3 parts by mass The above polymer (A) 0.08 parts by mass The above polymer (B) 0.50 parts by mass Methylisobutylketone 116 parts by mass Propion 40 parts by mass of ethyl acid acid ⁇
  • the optical film (F-3) produced above was cut in parallel with the rubbing direction, and the optically anisotropic layer was observed from the cross-sectional direction with a polarizing microscope.
  • the thickness of the optically anisotropic layer is 2.7 ⁇ m
  • the region (second region) having a thickness of 1.1 ⁇ m on the substrate side of the optically anisotropic layer is homogeneously oriented
  • the air side (substrate) of the optically anisotropic layer is
  • the liquid crystal compound was in an isotropic state (isotropic phase) in the region (first region) having a thickness of 1.6 ⁇ m (on the opposite side).
  • the optical characteristics of the optical film (F-3) were determined using Axoscan of Axometrics and analysis software (Multi-Layer Analysis) of the same company.
  • the in-plane retardation ( ⁇ n2d2) at a wavelength of 550 nm in the second region was 140 nm, and the in-plane slow phase axis was ⁇ 45 °.
  • the in-plane retardation ( ⁇ n1d1) at a wavelength of 550 nm in the first region was 0 nm, and the retardation in the thickness direction was 0 nm.
  • the angle of the in-plane slow-phase axis is 0 ° with respect to the longitudinal direction of the film, and the substrate is observed from the surface side of the optically anisotropic layer. Clockwise (clockwise) is negative and counterclockwise. The time of (counterclockwise) is expressed as positive.
  • Example 3 (Making a circular polarizing plate)
  • the optical film (F-3) produced above is sacrificed, and the above-mentioned polarizing element and the above-mentioned polarizing element protection film are polyvinyl-coated on the substrate surface contained in the optical film (F-3).
  • a long circular polarizing plate (P-3) was prepared by continuously laminating them using an alcohol-based adhesive. That is, the circularly polarizing plate (P-3) had a polarizing element protective film, a polarizing element, a substrate, and an optically anisotropic layer in this order.
  • the absorption axis of the polarizing element coincided with the longitudinal direction of the circular polarizing plate, and the rotation angle of the in-plane slow-phase axis of the second region with respect to the absorption axis of the polarizing element was 45 °.
  • the rotation angle of the in-plane slow-phase axis is set to 0 ° with respect to the longitudinal direction of the circularly polarizing plate by observing the optically anisotropic layer from the substituent side, and is positive and clockwise in the counterclockwise direction. It is represented by a negative angle value.
  • Example 4 (Formation of optically anisotropic layer)
  • the cellulose acylate film produced in Example 1 was continuously subjected to a rubbing treatment. At this time, the longitudinal direction of the long film and the conveying direction were parallel, and the angle between the longitudinal direction of the film (transporting direction) and the rotation axis of the rubbing roller was 90 °.
  • the composition for forming an optically anisotropic layer (4) containing a rod-shaped liquid crystal compound having the following composition is applied using a Gieser coating machine to form a composition layer.
  • the absolute value of the weighted average spiral inducing force of the chiral agent in the composition layer in step 1B was 31 ⁇ m -1 .
  • the obtained composition layer was heated at 100 ° C. for 80 seconds (corresponding to step 2B). By this heating, the rod-shaped liquid crystal compound of the composition layer was oriented in a predetermined direction.
  • the composition layer was irradiated with ultraviolet rays for 10 seconds using a 365 nm LED lamp (manufactured by Acroedge Co., Ltd.) at 40 ° C. under oxygen-containing air (oxygen concentration: about 20% by volume) (irradiation amount:). 100 mJ / cm 2 ) (corresponding to step 3B). Subsequently, the obtained composition layer was heated at 90 ° C. for 10 seconds (corresponding to step 4B). After that, nitrogen purging was performed to irradiate the composition layer with ultraviolet rays using a metal halide lamp (manufactured by Eye Graphics Co., Ltd.) at 55 ° C.
  • a metal halide lamp manufactured by Eye Graphics Co., Ltd.
  • the molar extinction coefficient of the sensitizer (Kayacure DETX) at 365 nm was 4200 L / (mol ⁇ cm).
  • ⁇ Composition for forming an optically anisotropic layer (4) 80 parts by mass of the above-mentioned rod-shaped liquid crystal compound (A) 10 parts by mass of the above-mentioned rod-shaped liquid crystal compound (C) 10 parts by mass of the above-mentioned rod-shaped liquid crystal compound (C) Ethylene oxide-modified trimethylolpropane triacrylate (V # 360, Osaka Organic Chemistry (V # 360, Osaka Organic Chemistry) (Manufactured by Co., Ltd.) 4 parts by mass Photopolymerization initiator (Irgacure907, manufactured by BASF) 3 parts by mass Sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 1 part by mass Right-handed twist chiral agent (R1) 11 mass Part
  • the above polymer (B) 0.5 parts by mass Methyl isobutyl ketone 117 parts by mass Eth
  • the optical film (F-4) produced above was cut in parallel with the rubbing direction, and the optically anisotropic layer was observed from the cross-sectional direction by SEM.
  • the thickness of the optically anisotropic layer is 3.6 ⁇ m, and the region having a thickness of 1.8 ⁇ m on the substrate side of the optically anisotropic layer (second region) and the air side of the optically anisotropic layer (opposite to the substrate). It has a region (first region) with a thickness of 1.8 ⁇ m, and the second region and the first region have cholesteric orientations with different spiral pitches.
  • the spectral reflectance characteristics of the optical film (F-4) were determined using an integrated reflectance meter. It was confirmed that the two-band cholesteric liquid crystal film has a reflection band centered on 450 nm derived from the second region and a reflection band centered on 650 nm derived from the first region.
  • Example 1 ⁇ Comparative Example 1>
  • the irradiation with the 365 nm LED lamp was carried out under nitrogen purge (oxygen concentration 100% by volume ppm) instead of being carried out under oxygen-containing air (oxygen concentration: about 20% by volume).
  • An optical film (C-1) was produced in the same manner as in the method for producing an optical film (F-1) according to the same procedure as in Example 1. That is, in Comparative Example 1, step 3A was not carried out.
  • step 3A was not carried out.
  • the cross section of the optically anisotropic layer was observed according to the same procedure as in Example 1, the homogeneous orientation was formed over the entire thickness direction of the obtained optically anisotropic layer, which is desired by the present invention. No effect was obtained.
  • Example 2 In Example 1 described above, an optical film (except that after irradiation with a 365 nm LED lamp at 40 ° C., UV irradiation was performed at 40 ° C. using a metal halide lamp without heating to 80 ° C. An optical film (C-2) was produced in the same manner as in the production method of F-1). That is, in Comparative Example 2, step 4A was not carried out.
  • step 4A step 4A was not carried out.
  • the cross section of the optically anisotropic layer was observed according to the same procedure as in Example 1, the homogeneous orientation was formed over the entire thickness direction of the obtained optically anisotropic layer, which is desired by the present invention. No effect was obtained.
  • the irradiation conditions in the step 3A are the same as the method for producing the optical film (F-1) except that the irradiation with the 365 nm LED lamp is changed to 100 seconds (irradiation amount: 13 mJ / cm 2 ).
  • An optical film (C-3) was produced. That is, in Comparative Example 3, the irradiation amount was the same as that in Example 1, but the irradiation time was lengthened.
  • the cross section of the optically anisotropic layer was observed according to the same procedure as in Example 1, the twisted orientation was formed over the entire thickness direction of the obtained optically anisotropic layer, which is desired by the present invention. No effect was obtained.
  • in-plane retardation indicates in-plane retardation at each wavelength of the optically anisotropic layer.
  • the phase difference of the optically anisotropic layer in each embodiment shows anti-wavelength dispersibility, and when this optically anisotropic layer is used in an organic EL display device, coloring and reflection occur. It was confirmed that it was suppressed.
  • the rotation angle of the in-plane slow-phase axis of the second region with respect to the polarizing element absorption axis is 100 °, and the in-plane delay of the surface of the surface opposite to the second region side of the first region with respect to the polarizing element absorption axis.
  • the rotation angle of the phase axis was 175 °.
  • the rotation angle of the in-plane slow-phase axis is set to 0 ° with respect to the absorption axis direction of the substituent by observing the optically anisotropic layer from the splitter side, and is positive and clockwise in the counterclockwise direction. It is represented by a negative angle value.
  • a semi-transmissive liquid crystal display device 1 in VA mode was manufactured as follows. Polyimide was used for the alignment film of the liquid crystal cell, the cell gap of the transmissive part was 4.0 ⁇ m, and the cell gap of the reflective part was 2.0 ⁇ m. A nematic liquid crystal having a negative dielectric anisotropy was injected into this space. When no voltage was applied to the upper and lower substrates of this liquid crystal cell, the nematic liquid crystal was vertically oriented. Further, when a voltage was applied, protrusions were formed on the cell substrate so that the nematic liquid crystal was tilted in two directions in which the orientations differed by 180 °.
  • the in-plane retardation at a wavelength of 550 nm when a voltage is applied to the liquid crystal cell and displayed in white is 280 nm in the transmitting portion and 140 nm in the reflecting portion, and the in-plane retardation at a wavelength of 550 nm when displaying in black without application is
  • the transmissive part was 0 nm and the reflective part was 0 nm.
  • the circular polarizing plate (P-1) and the circular polarizing plate (P-4) produced above are attached to a liquid crystal cell composed of the upper and lower substrates and a liquid crystal layer sandwiched between the substrates to display a semi-transmissive liquid crystal display.
  • the device 1 was manufactured.
  • the circularly polarizing plate (P-1), the liquid crystal cell, the circularly polarizing plate (P-4), and the backlight were arranged in this order from the observer side.
  • the circularly polarizing plate (P-1) is in this order from the observer side, and the polarizing element and the optical film (F-1) are in this order, and the circularly polarizing plate (P-4) is the optical film (P-4) from the observer side.
  • the F-1) and the polarizing elements are arranged in this order, and the angle formed by the absorption axis of each of the polarizing plates included in the circularly polarizing plate (P-1) and the circularly polarizing plate (P-4) is 90 °. Arranged so as to be.
  • the rotation angle in the direction in which the long axis of the nematic liquid crystal was projected onto the cell substrate was 45 °.
  • the rotation angle in the projected direction is set to 0 ° with respect to the absorption axis direction of the polarizing element by observing the liquid crystal cell from the circular polarizing plate (P-1) side, and counterclockwise. It is represented by a positive angle value in the clockwise direction and a negative angle value in the clockwise direction.
  • An optically anisotropic layer H made of a discotic liquid crystal compound is formed on an alignment film on a cellulose acylate film in the same manner as in the method described in Example 1 or Example 25 of Patent 6770649.
  • an optically anisotropic layer Q made of a rod-shaped liquid crystal compound was produced.
  • the thickness and rubbing angle of the coating layer were adjusted so as to have the following retardation and the slow axis angle.
  • the in-plane retardation of the optically anisotropic layer H at a wavelength of 550 nm was 280 nm
  • the in-plane retardation of the optically anisotropic layer Q at a wavelength of 550 nm was 120 nm.
  • the optically anisotropic layer Q, the optically anisotropic layer H, the above-mentioned polarizing element, and the above-mentioned polarizing element protective film are bonded together using an adhesive so as to be in this order, and a circular polarizing plate (P-) is attached. 5) was produced.
  • the cellulose acylate film and the alignment film were separated from the optically anisotropic layer H and the optically anisotropic layer Q so as not to be included in the circularly polarizing plate.
  • the rotation angle of the in-plane slow-phase axis of the optically anisotropic layer H with respect to the absorption axis of the polarizing element is ⁇ 75 °
  • the rotation of the in-plane slow-phase axis of the optically anisotropic layer Q with respect to the absorption axis of the polarizing element is ⁇ 75 °. They were pasted together so that the angle was -15 °.
  • the rotation angle of the in-plane slow-phase axis is set to 0 ° with respect to the absorption axis direction of the substituent by observing the optically anisotropic layer from the splitter side, and is positive and clockwise in the counterclockwise direction. It is represented by a negative angle value.
  • An ECB mode semi-transmissive liquid crystal display device 2 was manufactured as follows.
  • the alignment film of the liquid crystal cell was polyimide, and the rubbing direction was set so that the top and bottom were parallel.
  • the cell gap of the transmissive part was 4.0 ⁇ m and the cell gap of the reflective part was 2.0 ⁇ m, and a nematic liquid crystal having a positive dielectric anisotropy was injected into this gap.
  • the in-plane retardation at a wavelength of 550 nm when a voltage is applied to this liquid crystal cell is as follows: a transmissive part at white display is 280 nm, a reflective part at white display is 140 nm, a transmissive part at black display is 40 nm, and a reflective part at black display. was 20 nm. Further, when the nematic liquid crystal sandwiched between the upper and lower substrates was tilted by applying a voltage, the direction in which the long axis of the nematic liquid crystal was projected onto the cell substrate (in-plane slow phase axis) coincided with the rubbing direction.
  • the circular polarizing plate (P-1) and the circular polarizing plate (P-5) produced above are attached to a liquid crystal cell composed of the upper and lower substrates and a liquid crystal layer sandwiched between the substrates to display a semi-transmissive liquid crystal display.
  • the device 2 was manufactured.
  • the circularly polarizing plate (P-5), the liquid crystal cell, the circularly polarizing plate (P-1), and the backlight were arranged in this order from the observer side.
  • the splitter, the optically anisotropic layer H, and the optically anisotropic layer Q are in this order from the observer side, and the circularly polarizing plate (P-1) is the observer.
  • the optical film (F-1) and the polarizing element were arranged in this order. Further, the angle formed by the absorption axes of the polarizing plates included in the circular polarizing plate (P-5) and the circular polarizing plate (P-1) is set to 90 °, and the rubbing direction is applied to the alignment film of the liquid crystal cell. And the optically anisotropic layer Q contained in the circularly polarizing plate (P-5) were arranged so that the angle formed by the in-plane slow phase axial direction was 0 °.
  • the applied voltage was adjusted for the transmissive portion and the reflective portion of the VA mode semi-transmissive liquid crystal display device 1 and the ECB mode liquid crystal display device 2 produced above, and the visibility of the black display and the white display was visually evaluated. It was confirmed that the optically anisotropic layer of this example can be suitably used for the liquid crystal display device, showing good white / black contrast in any of the display devices.
  • Example 5 (Formation of optically anisotropic layer)
  • the alignment film prepared in Example 2 was continuously subjected to a rubbing treatment. At this time, the longitudinal direction of the long film and the conveying direction are parallel, and the angle between the longitudinal direction of the film (transporting direction) and the rotation axis of the rubbing roller is 90 °.
  • the composition (5) for forming an optically anisotropic layer containing a rod-shaped liquid crystal compound having the following composition is applied using a Gieser coating machine to obtain a composition.
  • a layer was formed (corresponding to step 1C).
  • the obtained composition layer was heated at 120 ° C. for 80 seconds (corresponding to step 2C).
  • the rod-shaped liquid crystal compound of the composition layer was oriented in a predetermined direction.
  • the composition layer was irradiated with ultraviolet rays for 5 seconds using a 365 nm LED lamp (manufactured by Acroedge Co., Ltd.) at 40 ° C.
  • the optical film (F-5) produced above was cut in parallel with the rubbing direction, and the optically anisotropic layer was observed from the cross-sectional direction with a polarizing microscope.
  • the thickness of the optically anisotropic layer is 4.3 ⁇ m, and the region (second region) having a thickness of 2.4 ⁇ m on the substrate side of the optically anisotropic layer is homogenously oriented, and the air side (substrate) of the optically anisotropic layer.
  • the liquid crystal compound was homeotropically oriented in the region (first region) having a thickness of 1.9 ⁇ m (on the opposite side).
  • the optical characteristics of the optical film (F-5) were determined using Axoscan of Axometrics and analysis software (Multi-Layer Analysis) of the same company.
  • the in-plane retardation ( ⁇ n2d2) at a wavelength of 550 nm in the second region was 130 nm, and the angle of the in-plane slow phase axis with respect to the longitudinal direction of the film was 0 °.
  • the in-plane retardation ( ⁇ n1d1) at a wavelength of 550 nm in the first region was 0 nm, and the retardation in the thickness direction at a wavelength of 550 nm in the first region was ⁇ 100 nm.
  • the angle of the in-plane slow phase axis is 0 ° with respect to the longitudinal direction of the film.
  • the optical film (F-5) produced above is sacinified, and the above-mentioned polarizing element and the above-mentioned polarizing element protective film are applied to the optically anisotropic layer surface contained in the optical film (F-5) with a polyvinyl alcohol-based adhesive.
  • a long polarizing plate (P-6) was prepared by continuously laminating with each other. That is, the polarizing plate (P-6) had a polarizing element protective film, a polarizing element, an optically anisotropic layer, and a substrate in this order.
  • the absorption axis of the polarizing element coincided with the longitudinal direction of the polarizing plate, and the rotation angle of the in-plane slow-phase axis of the second region with respect to the absorption axis of the polarizing element was 0 °.
  • the rotation angle of the in-plane slow-phase axis is set to 0 ° with respect to the longitudinal direction of the polarizing plate by observing the optically anisotropic layer from the splitter side.
  • the polarizing plate (P-6) produced above was obtained by peeling off the polarizing plate on the front side from a commercially available liquid crystal display device (iPad (registered trademark), manufactured by Apple) (a liquid crystal display device including a liquid crystal cell in FFS mode). Attach with a 20 ⁇ m acrylic adhesive so that the optical film side is arranged on the liquid crystal cell side and the absorption axis of the polarizing element is orthogonal to the absorption axis of the polarizing element in the polarizing plate on the backlight side.
  • iPad registered trademark
  • a liquid crystal display device 3 was manufactured.
  • Substrate 12 120, 220, 320, 420 Composition layer 12A, 120A, 220A, 320A, 420A Lower region 12B, 120B, 220B, 320B, 420B Upper region 20
  • Optical anisotropy layer 22 Other optical anisotropy Layer 24
  • Laminated body 26 Polarizer 28

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Abstract

La présente invention concerne un procédé pratique de fabrication d'une couche optiquement anisotrope dans laquelle l'état d'alignement d'un composé à cristaux liquides est fixé, ladite couche optiquement anisotrope ayant, le long de la direction de l'épaisseur, une pluralité de régions ayant différentes conditions d'alignement de composé cristallin liquide. Ce procédé de fabrication d'une couche optiquement anisotrope comprend : une étape 1 dans laquelle une couche de composition qui comprend un composé de cristaux liquides ayant un groupe polymérisable est formée ; une étape 2 dans laquelle la couche de composition est soumise à un traitement de chauffage pour provoquer l'alignement du composé de cristaux liquides à l'intérieur de la couche de composition ; une étape 3 dans laquelle, après l'étape 2, la couche de composition est photoirradiée pendant 50 secondes ou moins et à 300 mJ/cm2 ou moins, dans des conditions dans lesquelles la concentration en oxygène est égale ou supérieure à 1 % en volume ; une étape 4 dans laquelle, après l'étape 3, la couche de composition est soumise à un traitement de chauffage à une température plus élevée que pendant la photopolymérisation ; et une étape 5 dans laquelle, après l'étape 4, la couche de composition est soumise à un traitement de durcissement pour former une couche optiquement anisotrope ayant, le long de la direction de l'épaisseur, une pluralité de régions ayant différentes conditions d'alignement de composé cristallin liquide.
PCT/JP2021/027346 2020-08-04 2021-07-21 Procédé de fabrication de couche optiquement anisotrope WO2022030266A1 (fr)

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JP2014199359A (ja) * 2013-03-29 2014-10-23 富士フイルム株式会社 ３ｄ画像表示装置用光学フィルムおよびその製造方法、偏光板、３ｄ画像表示装置
WO2015005122A1 (fr) * 2013-07-08 2015-01-15 富士フイルム株式会社 Film optique, polariseur, dispositif d'affichage d'image et dispositif de fabrication de film optique
JP2015087472A (ja) * 2013-10-29 2015-05-07 日本ゼオン株式会社 物品の製造方法、及び偽造防止媒体
WO2018030190A1 (fr) * 2016-08-09 2018-02-15 Jnc株式会社 Composition de cristaux liquides polymérisable et polymère à cristaux liquides

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JP2004145071A (ja) * 2002-10-25 2004-05-20 Fuji Photo Film Co Ltd 位相差板及びその製造方法
JP2010112986A (ja) * 2008-11-04 2010-05-20 Konica Minolta Opto Inc 光学フィルムの製造方法、光学フィルムの製造装置、光学フィルムおよび液晶表示装置
JP2014199359A (ja) * 2013-03-29 2014-10-23 富士フイルム株式会社 ３ｄ画像表示装置用光学フィルムおよびその製造方法、偏光板、３ｄ画像表示装置
WO2015005122A1 (fr) * 2013-07-08 2015-01-15 富士フイルム株式会社 Film optique, polariseur, dispositif d'affichage d'image et dispositif de fabrication de film optique
JP2015087472A (ja) * 2013-10-29 2015-05-07 日本ゼオン株式会社 物品の製造方法、及び偽造防止媒体
WO2018030190A1 (fr) * 2016-08-09 2018-02-15 Jnc株式会社 Composition de cristaux liquides polymérisable et polymère à cristaux liquides

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