Classifications

• • 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
• • 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
  • C09K19/02—Liquid crystal materials characterised by optical, electrical or physical properties of the components, in general
• • 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
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/06—Non-steroidal liquid crystal compounds
  • C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
  • C09K19/10—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings
  • C09K19/20—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters or ethers
  • C09K19/2007—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters or ethers the chain containing -COO- or -OCO- groups
• • 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
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/38—Polymers
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
  • G02B1/08—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of polarising materials
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B5/00—Optical elements other than lenses
  • G02B5/30—Polarising elements

Definitions

• the present invention relates to a method for producing an optically anisotropic layer.
• Optical films such as optical compensation sheets and retardation films are used in various image display devices to eliminate image coloration and / or expand the viewing angle.
• a stretched birefringent film has been used as the optical film, but in recent years, an optically anisotropic layer formed using a liquid crystal compound instead of the stretched birefringent film has been proposed.
• Patent Document 1 discloses a method for producing an optically anisotropic layer for producing an optically anisotropic layer fixed in a smectic phase.
• an optically anisotropic layer is produced through a heating process, a cooling heating process, and a polymerization process for an uncured layer made of a polymerizable liquid crystal composition (Claim 1).
• the optically anisotropic layer is often used by being incorporated in electronic devices. For this reason, the optically anisotropic layer is required to have durability capable of exhibiting stable performance for a long time even under a severe environment such as a high temperature.
• the optically anisotropic layer has excellent contrast (hereinafter referred to as “film”). Abbreviated as "contrast").
• panel contrast the contrast of an image display device using a polarizing plate including a polarizer and an optically anisotropic layer
• panel contrast excellent contrast
• an object of the present invention is to provide a method for producing an optically anisotropic layer having excellent durability and film contrast and capable of producing an image display device having excellent panel contrast.
• Step A for forming an uncured layer containing a polymerizable liquid crystal compound, Step B for forming a nematic phase by subjecting the uncured layer to a heat treatment; Step C for forming a smectic phase by subjecting the uncured layer on which the nematic phase has been formed to a cooling treatment; A step D of performing a first exposure treatment on the uncured layer on which the smectic phase has been formed to form a semi-cured layer; A step E of forming an optically anisotropic layer by subjecting the semi-cured layer to a second exposure process under a temperature condition higher than the temperature during the first exposure process.
• a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
• the temperature of a layer such as an uncured layer to be described later
• the temperature of the surface of the layer is a temperature measured with a radiation thermometer.
• the smectic phase refers to a state in which molecules aligned in one direction have a layer structure
• the nematic phase refers to a three-dimensional positional order, although the constituent molecules have orientational order. The state that does not have.
• the phase transition temperature is determined by observing the uncured layer formed on the alignment film using a central processor FP90 (Mettler TOLEDO) and an optical microscope while heating or cooling the uncured layer. The temperature at which the change occurred was defined as the phase transition temperature. The uncured layer will be described later.
• Re ( ⁇ ) and Rth ( ⁇ ) represent in-plane retardation and retardation in the thickness direction at a wavelength ⁇ , respectively.
• Re (450) represents in-plane retardation at a wavelength of 450 nm.
• the wavelength ⁇ is 550 nm.
• Re ( ⁇ ) and Rth ( ⁇ ) are values measured at wavelength ⁇ in AxoScan OPMF-1 (manufactured by Optoscience).
• the average refractive index values of main optical films are exemplified below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), And polystyrene (1.59).
• the bonding direction of a divalent group (for example, —CO—O—) represented is not particularly limited.
• L 1 in the general formula (W) described later is —CO—O.
• W the bonding direction of a divalent group represented is not particularly limited.
• L 1 in the general formula (W) described later is —CO—O.
• L 1 is * 1-CO-O- * 2. It may be * 1-O-CO- * 2.
• the method for producing an optically anisotropic layer of the present invention includes the following steps A to E.
• Step A Step of forming an uncured layer containing a polymerizable liquid crystal compound (layer formation step).
• Step B Step B (nematic phase forming step) in which the uncured layer is heated to form a nematic phase.
• Step C A step of cooling the uncured layer on which the nematic phase has been formed to form a smectic phase (cooling step).
• Step D A step of performing a first exposure treatment on the uncured layer on which the smectic phase is formed to form a semi-cured layer (first polymerization step).
• Step E The semi-cured layer is subjected to a second exposure treatment under a temperature condition higher than the temperature during the first exposure treatment to form an optically anisotropic layer (second polymerization step).
• the reason why the problem of the present invention can be solved by taking such a configuration is not necessarily clear, but the present inventors consider as follows.
• the first exposure treatment is performed on the uncured layer that is cooled to a temperature lower than the phase transition temperature between the smectic phase and the nematic phase and is in the smectic phase state, thereby providing excellent orientation of the smectic phase.
• the molecular packing of the optically anisotropic layer finally obtained can be improved. Therefore, the optically anisotropic layer of the present invention is excellent in film contrast, and an image display device with excellent panel contrast can be obtained when incorporated in an image display device.
• the second exposure process is performed on the semi-cured layer obtained at a higher temperature than when the first exposure process is performed. It is considered that an optically anisotropic layer having a higher polymerization rate and excellent durability than that obtained by continuing exposure at the temperature in one exposure process was obtained.
• each process which the manufacturing method of the optically anisotropic layer of this invention has is demonstrated in detail.
• Step A is a step of forming an uncured layer containing a polymerizable liquid crystal compound.
• the uncured layer is a layer that contains a polymerizable liquid crystal compound and has not been subjected to a curing process such as a first exposure process and a second exposure process described later. As will be described later, the uncured layer shows a nematic phase and a smectic phase in this order on the lower temperature side than the isotropic phase.
• the uncured layer When forming the uncured layer, it is preferable to form the uncured layer using a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound. More specifically, the uncured layer is preferably formed by, for example, applying a polymerizable liquid crystal composition on a substrate to form the uncured layer. Examples of the substrate include a support and a polarizer. An alignment film may be further disposed on the support. Each component contained in the polymerizable liquid crystal composition will be described in detail later.
• the method for applying the polymerizable liquid crystal composition is not particularly limited, and a known method can be adopted. Examples include screen printing, dip coating, spray coating, spin coating, ink jet, gravure offset printing, and flexographic printing.
• the coating amount is preferably such that the thickness of the uncured layer in a state where the solvent or the like is removed is 0.1 to 10 ⁇ m, and more preferably, the coating amount is 0.5 to 5 ⁇ m.
• Step B is a step in which a heat treatment is performed on the uncured layer to form a nematic phase.
• the procedure of the nematic phase forming step is not particularly limited as long as the temperature of the uncured layer is heated to a temperature equal to or higher than the phase transition temperature between the smectic phase and the nematic phase so that the uncured layer can be converted into the nematic phase.
• the temperature of the uncured layer (first heating temperature) adjusted by the heating is equal to or higher than the phase transition temperature between the smectic phase and the nematic phase.
• the first heating temperature is preferably 0 to 83 ° C higher than the phase transition temperature between the smectic phase and the nematic phase at the time of temperature rise, more preferably 2 to 53 ° C higher, and further 2 to 37 ° C higher. preferable.
• the uncured layer is preferably maintained for a certain period of time in a state where a nematic phase is formed. Such a holding time is preferably 1 second to 10 minutes, more preferably 5 seconds to 5 minutes or less, and even more preferably 5 to 30 seconds. During the holding time, the temperature of the uncured layer is preferably maintained within a range of ⁇ 5 ° C. from the first heating temperature.
• the means for adjusting the temperature of the uncured layer is not particularly limited, and for example, a hot plate or an oven may be used. The same applies to the temperature operation of each layer described in the following steps.
• Step C is a step of forming a smectic phase by subjecting the uncured layer on which the nematic phase has been formed in step B (nematic phase forming step) to a cooling treatment.
• the temperature (cooling temperature) of the uncured layer that has been subjected to the cooling treatment in the cooling step is not particularly limited as long as the uncured layer can form a smectic phase, and is higher than the temperature at which crystals start to be generated in the uncured layer. Is preferred.
• the cooling temperature is preferably 0 to 60 ° C.
• the temperature decrease rate (temperature decrease rate) of the uncured layer during cooling in the cooling step is 0.5 to 200 ° C. / Min is preferable, 1 to 100 ° C./min is more preferable, 1 to 80 ° C./min is more preferable, and 1 to 60 ° C./min is particularly preferable.
• the temperature drop rate is obtained by dividing the temperature difference between the first heating temperature and the cooling temperature by the time taken to reach the cooling temperature from the start of the cooling process.
• the temperature of the uncured layer is gradually decreased. Note that “the temperature gradually decreases” means that the temperature of the uncured layer is decreasing as a whole in the cooling step. In other words, it is intended that no significant temperature increase occurs in the uncured layer from the start of the temperature drop until the cooling temperature is reached.
• the uncured layer forming the nematic layer can be made into a smectic phase.
• the uncured layer forming the nematic layer is placed on a hot plate set higher than the phase transition temperature between the crystalline phase and the smectic phase and lower than the phase transition temperature between the smectic phase and the nematic phase.
• a method of forming a smectic phase in the uncured layer is not limited.
• Step D is a step of forming a semi-cured layer by performing a first exposure process on the uncured layer in which the smectic phase is formed in Step C. It is preferable that a smectic phase is formed in the entire uncured layer when the first exposure treatment is performed.
• the light used for the first exposure treatment is preferably ultraviolet light
• the ultraviolet light is preferably ultraviolet light containing light having a wavelength of 365 nm.
• the exposure light source include metal halide lamps, mercury lamps (medium pressure mercury lamps, high pressure mercury lamps, ultra high pressure mercury lamps, etc.), xenon lamps, carbon arc lamps, fluorescent lamps (ultraviolet fluorescent lamps, etc.), LEDs (LED: light emitting diode, UV LED, etc.) and LD (LD: laser diode, ultraviolet LD, etc.). You may limit the wavelength range to irradiate with respect to the light obtained from the exposure light source using an interference filter or a color filter.
• the light from these exposure light sources may be polarized using a polarizing filter or a polarizing prism.
• the exposure amount in the first exposure treatment is not particularly limited as long as a semi-cured layer can be formed by polymerizing a part of the polymerizable groups contained in the polymerizable liquid crystal compound, as will be described later. Among them, the exposure amount (preferably the wavelength in the first exposure process) is preferred because the durability and film contrast of the optically anisotropic layer and the panel contrast when the optically anisotropic layer is incorporated in an image display device are excellent in a balanced manner.
• integrated exposure amount of 300 ⁇ 390 nm is preferably 0.5 ⁇ 100mJ / cm 2, more preferably 1 ⁇ 60mJ / cm 2, more preferably 10 ⁇ 30mJ / cm 2.
• inert gas atmosphere such as nitrogen gas
• a semi-cured layer is obtained by the first exposure process described above.
• the semi-cured layer is a layer obtained by polymerizing a part of the polymerizable group contained in the polymerizable liquid crystal compound, and the polymerizable group derived from the polymerizable liquid crystal compound remains in the semi-cured layer.
• the residual ratio of the polymerizable group derived from the polymerizable liquid crystal compound after the first exposure treatment is preferably 10% or more, and more preferably 20% or more.
• the upper limit is preferably 90% or less, more preferably 80% or less, after the first exposure treatment.
• the residual ratio is the amount of the polymerizable group derived from the polymerizable liquid crystal compound in the semi-cured layer after the first exposure treatment and the polymerizable group derived from the polymerizable liquid crystal compound in the uncured layer before the first exposure treatment. Calculated by comparing the quantity. Specifically, by an infrared spectrophotometer, a peak derived from a polymerizable group in an uncured layer and a peak derived from a structure (for example, a carbonyl group) in a polymerizable liquid crystal compound whose intensity does not change before and after exposure. The ratio X is calculated.
• the ratio Y between the peak derived from the polymerizable group in the semi-cured layer and the peak derived from the structure (for example, carbonyl group) in the polymerizable liquid crystal compound whose intensity does not change before and after exposure is calculated.
• the residual ratio can be calculated by the formula: ratio Y / ratio X ⁇ 100.
• Step E is a step of forming an optically anisotropic layer by subjecting the semi-cured layer to a second exposure treatment under a temperature condition higher than the temperature during the first exposure treatment.
• the temperature condition higher than the temperature during the first exposure process means that the temperature of the semi-cured layer when the second exposure process is performed is higher than the temperature of the uncured layer when the first exposure process is performed.
• a heat treatment is performed on the semi-cured layer obtained through the first polymerization step.
• the second exposure process may be started simultaneously with the second heat treatment, or may be performed after the semi-cured layer reaches a predetermined temperature by the second heat treatment.
• the second exposure treatment may be performed while increasing the temperature of the semi-cured layer, or may be performed while keeping the temperature of the semi-cured layer constant.
• the temperature of the semi-cured layer rising by the second heat treatment (temperature difference between the semi-cured layers before and after the second heat treatment. In other words, the difference between the temperature during the first exposure treatment and the temperature during the second exposure treatment). Is preferably 10 ° C. or higher, more preferably 20 ° C. or higher, and even more preferably 40 ° C. or higher from the viewpoint that the durability of the obtained optically anisotropic layer is more excellent.
• the upper limit is preferably 160 ° C. or lower.
• the temperature of the semi-cured layer at the time of the second exposure treatment (second heating temperature) is the difference between the smectic phase and the nematic phase at the time of raising the temperature of the uncured layer because the durability of the obtained optically anisotropic layer is more excellent.
• the rate of temperature increase (temperature increase rate) when the semi-cured layer is heated in the second heat treatment is preferably 0.5 to 250 ° C./min, more preferably 50 to 200 ° C./min, and 75 to 150 ° C./min. Minutes are more preferred.
• the temperature increase rate is obtained by dividing the temperature difference of the semi-cured layer before and after the second heat treatment by the time taken for the second heat treatment.
• the light used for the second exposure treatment is preferably ultraviolet light, and the ultraviolet light is preferably ultraviolet light containing light having a wavelength of 365 nm.
• the exposure light source the same exposure light source as exemplified in the description of the first exposure process is exemplified. You may limit the wavelength range to irradiate with respect to the light obtained from the exposure light source using an interference filter or a color filter. Further, the light from these exposure light sources may be polarized using a polarizing filter or a polarizing prism.
• Exposure amount in the second exposure process is preferably 100 ⁇ 10000 mJ / cm 2, more preferably 200 ⁇ 5000 mJ / cm 2, more preferably 400 ⁇ 1500mJ / cm 2.
• inert gas atmosphere such as nitrogen gas
• the optically anisotropic layer obtained by performing the second exposure treatment substantially contains no polymerizable group derived from the polymerizable liquid crystal compound.
• substantially means that the residual ratio of the polymerizable group derived from the polymerizable liquid crystal compound is 5% or less.
• the residual rate is determined by the amount of the polymerizable group derived from the polymerizable liquid crystal compound in the optically anisotropic layer and the amount of the polymerizable group derived from the polymerizable liquid crystal compound in the uncured layer before the first exposure treatment. Calculated by comparison. Specifically, the method using the infrared spectrophotometer mentioned above is mentioned.
• Polymerizable liquid crystal composition In the production method of the present invention, it is preferable to use a polymerizable liquid crystal composition. Hereinafter, the polymerizable liquid crystal composition will be described.
• the polymerizable liquid crystal composition includes a polymerizable liquid crystal compound.
• One or more of the polymerizable liquid crystal compounds used here are preferably polymerizable liquid crystal compounds capable of developing a nematic phase and a smectic phase.
• the polymerizable liquid crystal composition may contain other polymerizable liquid crystal compounds other than the polymerizable liquid crystal compound capable of developing a nematic phase and a smectic phase, but the polymerizable liquid crystal composition as a whole exhibits a nematic phase and a smectic phase.
• An uncured layer that can be formed must be able to be formed.
• the polymerizable liquid crystal compound is a liquid crystal compound having at least one polymerizable group.
• liquid crystal compounds can be classified into a rod-shaped type and a disk-shaped type based on their shapes.
• Polymer generally refers to a compound having a degree of polymerization of 100 or more (Polymer Physics / Phase Transition Dynamics, Masao Doi, 2 pages, Iwanami Shoten, 1992).
• any liquid crystal compound can be used as long as it has a polymerizable group and can form an uncured layer capable of expressing a smectic phase. Among these, it is preferable to use a rod-like polymerizable liquid crystal compound.
• the polymerizable liquid crystal compound preferably has two or more polymerizable groups in one molecule. Moreover, when using 2 or more types of polymeric liquid crystal compounds, it is preferable that at least 1 type of polymeric liquid crystal compound has 2 or more polymeric groups in 1 molecule. In addition, after the liquid crystal compound is fixed by polymerization, it is no longer necessary to exhibit liquid crystallinity, but the layer thus formed may be referred to as a liquid crystal layer for convenience.
• the kind of the polymerizable group which the polymerizable liquid crystal compound has is not particularly limited, and a functional group capable of addition polymerization reaction is preferable, and a polymerizable ethylenically unsaturated group or a ring polymerizable group is more preferable.
• a (meth) acryloyl group, a vinyl group, a styryl group, an allyl group, an epoxy group, or an oxetane group is preferable, and a (meth) acryloyl group is more preferable because the polymerization reaction is fast.
• Polymerizable liquid crystal compound capable of developing smectic phase examples include those described in JP-A-2016-51178, JP-A-2008-214269, JP-A-2008-19240, and JP-A-2006-276721. Compounds.
• the rod-like polymerizable liquid crystal compound is preferably a polymerizable liquid crystal compound having a maximum absorption wavelength in the wavelength range of 330 to 380 nm.
• the rod-like polymerizable liquid crystal compound is preferably a reverse wavelength dispersible polymerizable liquid crystal compound.
• that the polymerizable liquid crystal compound is reverse wavelength dispersive means that a specific wavelength (such as an optically anisotropic layer) of a retardation film produced using such a polymerizable liquid crystal compound ( When the in-plane retardation (Re) value in the visible light range) is measured, the Re value becomes equal or higher as the measurement wavelength increases.
• a polymerizable liquid crystal compound that can form an optically anisotropic layer satisfying the following formula is preferable. Re (450) / Re (550) ⁇ 1.00
• a compound represented by the general formula (W) is preferable as the polymerizable liquid crystal compound.
• n each independently represents an integer of 1 to 3.
• L 1 , L 2 , L 3 , L 4 , L 5 , and L 6 each independently represent a single bond or a divalent linking group.
• the divalent linking group include —CO—O—, —C ( ⁇ S) O—, —CR 1 R 2 —, —CR 1 R 2 —CR 3 R 4 —, —O—CR 1 R 2.
• R 1 , R 2 , R 3 and R 4 each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 4 carbon atoms.
• the plurality of L 3 may be the same or different.
• the plurality of L 4 may be the same or different.
• a 1 and A 2 are each independently an aromatic ring group having 6 or more carbon atoms or an alicyclic hydrocarbon group having 5 or more carbon atoms (preferably 5 to 8 carbon atoms). Represents. One or more of —CH 2 — constituting the alicyclic hydrocarbon group may be substituted with —O—, —S— or —NH—.
• the plurality of A 1 may be the same or different.
• the plurality of A 2 may be the same or different.
• the alicyclic hydrocarbon group having 5 or more carbon atoms represented by A 1 and A 2 is preferably a 5-membered or 6-membered ring group.
• the alicyclic hydrocarbon group may be saturated or unsaturated, but is preferably a saturated alicyclic hydrocarbon group.
• Examples of the alicyclic hydrocarbon group include a cyclohexane ring group (cyclohexane-1,4-diyl group and the like) and a cyclohexene ring group.
• the description in paragraph [0078] of JP2012-21068A can be referred to, and the contents thereof are incorporated in the present specification.
• Examples of the aromatic ring having 6 or more carbon atoms represented by A 1 and A 2 include aromatic hydrocarbon rings such as benzene ring, naphthalene ring, anthracene ring, and phenanthroline ring; furan ring, pyrrole ring, thiophene And aromatic heterocycles such as a ring, a pyridine ring, a thiazole ring, and a benzothiazole ring.
• aromatic hydrocarbon rings such as benzene ring, naphthalene ring, anthracene ring, and phenanthroline ring
• furan ring furan ring
• pyrrole ring thiophene
• aromatic heterocycles such as a ring, a pyridine ring, a thiazole ring, and a benzothiazole ring.
• a benzene ring for example, 1,4-phenylene group
• 1,4-phenylene group is preferable
• Sp 1 and Sp 2 are each independently a single bond, a linear or branched alkylene group having 1 to 12 carbon atoms, or a linear or branched group having 1 to 12 carbon atoms.
• Q represents a substituent (such as an alkyl group, an alkoxy group, or a halogen atom).
• the linear or branched alkylene group having 1 to 12 carbon atoms represented by Sp 1 and Sp 2 is, for example, preferably a methylene group, an ethylene group, a propylene group, or a butylene group.
• P 1 and P 2 each independently represent a monovalent organic group, and at least one of P 1 and P 2 represents a polymerizable group.
• MG is an aromatic ring represented by the following general formula (Ar-3)
• at least one of P 1 and P 2 and P 3 and P 4 in the general formula (Ar-3) is polymerized. Represents a sex group.
• the polymerizable group represented by P 1 and P 2 is not particularly limited, and is preferably a radical polymerizable group or a cationic polymerizable group.
• a radical polymerizable group a generally known radical polymerizable group can be used.
• an acryloyl group and a methacryloyl group are mentioned.
• the polymerization rate is generally high for acryloyl groups, and acryloyl groups are preferred from the viewpoint of improving productivity.
• a methacryloyl group can also be used as a polymerizable group of a highly birefringent liquid crystal.
• the cationic polymerizable group generally known cationic polymerizable groups can be used.
• Examples thereof include an alicyclic ether group, a cyclic acetal group, a cyclic lactone group, a cyclic thioether group, a spiro orthoester group, and a vinyloxy group.
• an alicyclic ether group or a vinyloxy group is preferable, and an epoxy group, an oxetanyl group, or a vinyloxy group is more preferable.
• particularly preferred polymerizable groups include the following. In the following polymerizable group, a black circle represents a bonding position.
• MG represents any aromatic ring selected from the group consisting of groups represented by the following general formulas (Ar-1) to (Ar-5).
• * 1 represents a bonding position with L 3
• * 2 represents a bonding position with L 4 .
• Q 1 represents N or CH
• Q 2 represents —S—, —O—, or —N (R 5 ) —
• R 5 represents Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms
• Y 1 is an aromatic hydrocarbon group having 6 to 12 carbon atoms or an aromatic group having 3 to 12 carbon atoms, which may have a substituent. Represents a heterocyclic group.
• Examples of the alkyl group having 1 to 6 carbon atoms represented by R 5 include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and an n-pentyl group. Group, n-hexyl group and the like.
• Examples of the aromatic hydrocarbon group having 6 to 12 carbon atoms represented by Y 1 include aryl groups such as a phenyl group, a 2,6-diethylphenyl group, and a naphthyl group.
• Examples of the aromatic heterocyclic group having 3 to 12 carbon atoms represented by Y 1 include a heteroaryl group such as a thienyl group, a thiazolyl group, a furyl group, and a pyridyl group.
• Examples of the substituent that Y 1 may have include an alkyl group, an alkoxy group, and a halogen atom.
• the alkyl group for example, a linear, branched or cyclic alkyl group having 1 to 18 carbon atoms is preferable, and an alkyl group having 1 to 8 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group).
• N-butyl group isobutyl group, sec-butyl group, t-butyl group, cyclohexyl group and the like, more preferably an alkyl group having 1 to 4 carbon atoms, and particularly preferably a methyl group or an ethyl group.
• an alkoxy group for example, an alkoxy group having 1 to 18 carbon atoms is preferable, and an alkoxy group having 1 to 8 carbon atoms (for example, a methoxy group, an ethoxy group, an n-butoxy group, and a methoxyethoxy group) is more preferable.
• an alkoxy group having 1 to 4 carbon atoms is more preferable, and a methoxy group or an ethoxy group is particularly preferable.
• a halogen atom a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, for example, Among these, a fluorine atom or a chlorine atom is preferable.
• Z 1 , Z 2 and Z 3 are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, A monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, —NR 6 R 7 , or —SR And R 6 to R 8 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and Z 1 and Z 2 may be bonded to each other to form an aromatic ring.
• the monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms is preferably an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms, a methyl group, an ethyl group, an isopropyl group, a tert group, -A pentyl group (1,1-dimethylpropyl group), a tert-butyl group, or a 1,1-dimethyl-3,3-dimethyl-butyl group is more preferable, and a methyl group, an ethyl group, or a tert-butyl group Is particularly preferred.
• Examples of the monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, methylcyclohexyl group, and Monocyclic saturated hydrocarbon groups such as ethylcyclohexyl group; cyclobutenyl group, cyclopentenyl group, cyclohexenyl group, cycloheptenyl group, cyclooctenyl group, cyclodecenyl group, cyclopentadienyl group, cyclohexadienyl group, cyclooctadienyl group, And monocyclic unsaturated hydrocarbon group such as cyclodecadiene; bicyclo [2.2.1] heptyl group, bicyclo [2.2.2] octy
• dodecyl group and polycyclic saturated hydrocarbon group such as adamantyl group; and the like.
• the monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms include a phenyl group, a 2,6-diethylphenyl group, a naphthyl group, and a biphenyl group, and an aryl group having 6 to 12 carbon atoms. (Especially phenyl group) is preferable.
• the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among them, a fluorine atom, a chlorine atom, or a bromine atom is preferable.
• examples of the alkyl group having 1 to 6 carbon atoms represented by R 6 to R 8 include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group.
• a 3 and A 4 are each independently —O—, —N (R 9 ) —, —S—, and —CO—.
• R 9 represents a hydrogen atom or a substituent. Examples of the substituent represented by R 9 include the same groups as the substituents that Y 1 in the general formula (Ar-1) may have.
• X represents a hydrogen atom or a non-metal atom of Groups 14 to 16 to which a substituent may be bonded.
• Examples of the non-metal atoms of Group 14 to 16 represented by X include an oxygen atom, a sulfur atom, a nitrogen atom having a substituent, and a carbon atom having a substituent.
• substituents examples include Alkyl group, alkoxy group, alkyl-substituted alkoxy group, cyclic alkyl group, aryl group (eg, phenyl group, naphthyl group, etc.), cyano group, amino group, nitro group, alkylcarbonyl group, sulfo group, hydroxyl group, etc. Can be mentioned.
• L 7 and L 8 are each independently a single bond, —CO—O—, —C ( ⁇ S) O—, —CR 1 R 2 —, —CR. 1 R 2 —CR 3 R 4 —, —O—CR 1 R 2 —, —CR 1 R 2 —O—CR 3 R 4 —, —CO—O—CR 1 R 2 —, —O—CO—CR 1 R 2 —, —CR 1 R 2 —O—CO—CR 3 R 4 —, —CR 1 R 2 —CO—O—CR 3 R 4 —, —NR 1 —CR 2 R 3 —, or — CO—NR 1 — is represented.
• R 1 , R 2 , R 3 and R 4 each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 4 carbon atoms.
• each of SP 3 and SP 4 is independently a single bond, a linear or branched alkylene group having 1 to 12 carbon atoms, or a group having 1 to 12 carbon atoms. 2 in which one or more of —CH 2 — constituting a linear or branched alkylene group is substituted with —O—, —S—, —NH—, —N (Q) —, or —CO—.
• Q represents a substituent. Examples of the substituent include the same groups as the substituents that Y 1 in the general formula (Ar-1) may have.
• P 3 and P 4 each independently represent a monovalent organic group, and a polymerizable group is preferable.
• Examples of the polymerizable group are as described in connection with P 1 and P 2 described above.
• at least one of P 1 and P 2 and P 3 and P 4 in the general formula (Ar-3) is Represents a polymerizable group.
• Ax has at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring, and has 2 to 30 carbon atoms. Represents an organic group.
• Ay represents a hydrogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, an aromatic hydrocarbon ring, and An organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of aromatic heterocycles.
• the aromatic ring in Ax and Ay may have a substituent, and Ax and Ay may combine to form a ring.
• Q 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent.
• Examples of Ax and Ay include groups described in paragraphs [0039] to [0095] of Patent Document 3 (International Publication No. 2014/010325).
• Examples of the alkyl group having 1 to 6 carbon atoms represented by Q 3 include, for example, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n -Pentyl group, n-hexyl group and the like can be mentioned, and examples of the substituent include the same groups as the substituent which Y 1 in the general formula (Ar-1) may have.
• liquid crystal compound represented by the general formula (W) Preferred examples of the liquid crystal compound represented by the general formula (W) are shown below, but are not limited to these liquid crystal compounds. Note that all 1,4-cyclohexylene groups in the following formulas are trans-1,4-cyclohexylene groups. In the following formula, n represents an integer of 1 to 12.
• the group adjacent to the acryloyloxy group represents a propylene group (a group in which a methyl group is substituted with an ethylene group), and is a regioisomer having a different methyl group position. Represents a mixture of bodies.
• the content of the polymerizable liquid crystal compound is preferably 50 to 100% by mass, more preferably 60 to 98% by mass, with respect to the total mass of the liquid crystal compound in the polymerizable liquid crystal composition, 65 More preferably, it is 95% by mass.
• the total mass of the liquid crystal compound is a mass including the mass when the polymerizable liquid crystal composition also includes a non-polymerizable liquid crystal compound.
• the total content is preferably within the above range.
• the content of the polymerizable liquid crystal compound is preferably 50 to 99.99% by mass and more preferably 65 to 99.9% by mass with respect to the total solid content of the polymerizable liquid crystal composition. 80 to 99.5% by mass is more preferable.
• the total content is preferably within the above range.
• the total solid content means a component that forms an optically anisotropic layer, and does not include a solvent. Moreover, if it is a component which forms an optically anisotropic layer, even if the property is a liquid form, it will be considered as solid content.
• the polymerizable liquid crystal composition preferably contains a photopolymerization initiator.
• the polymerization initiator used is preferably a photopolymerization initiator capable of initiating a polymerization reaction by ultraviolet irradiation.
• Examples of the photopolymerization initiator include oxime ester polymerization initiators, ⁇ -carbonyl polymerization initiators (for example, described in the specifications of US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether polymerization initiators ( For example, U.S. Pat. No.
• Oxadiazole-based polymerization initiator for example, described in US Pat. No. 4,221,970
• acylphosphine oxide-based polymerization initiator for example, Japanese Patent Publication No. 63-40799, Japanese Patent Publication No. 5
• JP-A-10-95788, JP-A-10-29997 an oxime ester polymerization initiator is preferable from the viewpoint that the curing proceeds uniformly when exposed and an optically anisotropic layer having more excellent orientation can be obtained.
• the content of the photopolymerization initiator is preferably 0.01 to 20% by mass, and preferably 0.1 to 8% by mass with respect to the total mass of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition. % Is more preferable.
• a polymerization initiator may be used individually by 1 type, and may be used 2 or more types. When using 2 or more types of polymerization initiators, the total content is preferably within the above range.
• the polymerizable liquid crystal composition preferably contains a surfactant from the viewpoint of maintaining a smooth surface on the air interface side when an uncured layer is formed and obtaining an optically anisotropic layer having better orientation.
• a surfactant a fluorine-based surfactant or a silicon-based surfactant is preferable because of its high leveling effect with respect to the amount added. From the viewpoint of preventing crying (bloom, bleed), the fluorine-based surfactant is used. An agent is more preferable.
• the surfactant include compounds described in paragraphs [0079] to [0102] of JP-A-2007-069471, and compounds represented by general formula (I) described in JP-A-2013-047204.
• the polymerizable liquid crystal composition may contain a solvent in order to improve the production suitability such as lowering the viscosity when forming the uncured layer.
• the solvent is not particularly limited, but is selected from at least one selected from the group consisting of ketones (including cyclic ketones such as cyclopentanone), esters, ethers, alcohols, alkanes, toluene, chloroform, and methylene chloride. More preferably, it is selected from at least one member selected from the group consisting of ketones, esters, ethers, alcohols, and alkanes, and is selected from at least one member selected from the group consisting of ketones, esters, ethers, and alcohols. Is more preferable.
• the polymerizable liquid crystal compound may contain other components other than those described above.
• a thermal polymerization initiator may be included.
• a chiral agent or the like may be used from the viewpoint of adjusting the orientation of the optically anisotropic layer.
• a non-polymerizable liquid crystal compound is used from the viewpoints of adjusting the viscosity, phase transition temperature, alignment uniformity of the polymerizable liquid crystal composition, film properties of the optically anisotropic layer, and adjusting the optical properties.
• the non-polymerizable liquid crystal compound may be a low molecular liquid crystal compound.
• the non-polymerizable liquid crystal compound may be a main chain type liquid crystal polymer or a side chain type liquid crystal polymer.
• a polymerization inhibitor an antioxidant, an ultraviolet absorber, and the like may be used.
• adjustment of liquid properties, and adjustment of film properties plasticizers, retardation adjusting agents, dichroic dyes, fluorescent dyes, photochromic dyes, thermochromic dyes, photoisomerization materials, photodimerization Materials, nanoparticles, thixotropic agents and the like may be added.
• the uncured layer formed using such a polymerizable liquid crystal composition preferably has a phase transition temperature between a smectic phase and a nematic phase of 80 ° C. or lower, for example, better film contrast and panel contrast. From such a viewpoint, it is more preferably 70 ° C. or higher and lower than 80 ° C.
• the thickness of the optically anisotropic layer produced by the production method of the present invention is not particularly limited, but is preferably 0.1 to 10 ⁇ m, and more preferably 0.5 to 5 ⁇ m.
• the optically anisotropic layer produced by the production method of the present invention is preferably a layer in which a smectic phase is fixed.
• a positive A plate As a preferred embodiment of the optically anisotropic layer, a positive A plate can be mentioned.
• the positive A plate there is a method in which a rod-like polymerizable liquid crystal compound is horizontally aligned.
• the in-plane retardation Re (550) is 100 to 160 nm (preferably 120 to 150 nm), it can be suitably used as a positive uniaxial ⁇ / 4 plate.
• Re (550) can be used as a positive uniaxial ⁇ / 2 plate with a range of 250 to 300 nm.
• Re (550) represents in-plane retardation of the optically anisotropic layer at a wavelength of 550 nm.
• the value of in-plane retardation can be measured using AxoScan OPMF-1 (manufactured by Opto Science).
• optically anisotropic layer is a positive C plate.
• the thickness direction retardation Rth (550) is, for example, 20 to 200 nm, and is preferably 50 to 120 nm from the viewpoint of imparting various optical compensation functions and / or viewing angle enhancement functions.
• optically anisotropic layer may be a negative A plate or a negative C plate.
• the A plate is defined as follows. There are two types of A plates, positive A plate (positive A plate) and 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 maximum) ) Is nx, the refractive index in the direction orthogonal to the in-plane slow axis is ny, and the refractive index in the thickness direction is nz, the positive A plate satisfies the relationship of the formula (A1)
• the negative A plate satisfies the relationship of the formula (A2).
• the positive A plate shows a positive value for Rth
• the negative A plate shows a negative value for Rth.
• the positive C plate satisfies the relationship of the formula (C1), and the negative C plate is The relationship of Formula (C2) is satisfied.
• the positive C plate shows a negative value for Rth, and the negative C plate shows a positive value for Rth.
• Formula (C1) nz> nx ⁇ ny
• Formula (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 that, for example, (nx ⁇ ny) ⁇ d (where d is the thickness of the film) is included in “nx ⁇ ny” when 0 to 10 nm, preferably 0 to 5 nm. It is.
• the wavelength dispersion of the optical anisotropy can be appropriately adjusted by adjusting the type and amount of the polymerizable liquid crystal compound and other components used in the polymerizable liquid crystal composition.
• the optically anisotropic layer preferably exhibits reverse wavelength dispersion.
• the optically anisotropic layer preferably satisfies the relationship of the following formula (II).
• ⁇ n (450) represents the difference in refractive index between the maximum refractive index direction and the orthogonal direction at a wavelength of 450 nm of the optically anisotropic layer
• ⁇ n (550) represents the optically anisotropic layer.
• the uncured layer may be disposed on a support or the like. That is, the optically anisotropic layer produced by the production method of the present invention may constitute a laminate together with layers other than the optically anisotropic layer.
• the support is not particularly limited, and among them, a long polymer film is preferable in terms of enabling continuous production.
• polymer films include polyolefin and cyclic olefin resins such as polypropylene and norbornene polymers; polyvinyl alcohol; polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polymethacrylates such as polymethyl methacrylate.
• the surface on the coating side of the support is smooth when the polymerizable liquid crystal composition is directly applied to the support to form the optically anisotropic layer.
• the surface roughness Ra is preferably 3 to 50 nm.
• the polymerizability in the support is prevented from preventing shape transfer and blocking phenomenon between the surfaces of the laminate.
• Anti-blocking treatment or mat treatment may be performed on the surface opposite to the surface on which the liquid crystal composition is applied.
• you may provide a knurling in the edge part of a laminated body.
• the support is peelable.
• the layer can be peeled off at the interface between the support and the optically anisotropic layer.
• an orientation layer and / or other layer (intermediate layer) described later is provided between the support and the optically anisotropic layer, an arbitrary layer between the support and the optically anisotropic layer is provided. It is preferable to be able to peel off at the interface or in the layer.
• ⁇ Alignment film> From the viewpoint that it is easy to obtain an optically anisotropic layer having better orientation, it is preferable to provide an alignment film on the support and further to provide the above-described optically anisotropic layer on the alignment film.
• a rubbing film made of an organic compound such as a polymer, an oblique deposition film of an inorganic compound, a film having a microgroove, and an organic compound
• examples thereof include films obtained by accumulating LB films (Langmuir-Blodgett films) formed by the Langmuir-Blodgett method using (for example, ⁇ -tricosanoic acid, dioctadecylmethylammonium chloride, or methyl stearylate).
• LB films Longmuir-Blodgett films
• a photo-alignment film is also preferable as the alignment film.
• Examples of the rubbing alignment film include polyimide, polyvinyl alcohol, a coating film of a polymer having a polymerizable group described in JP-A-9-152509, and JP-A-2005-97377 and JP-A-2005-99228. And alignment films described in JP-A-2005-128503.
• composition for forming a photo-alignment film used for the photo-alignment film that can be used in the present invention is described in many documents. For example, materials using azo compounds described in WO08 / 056597, JP2008-76839, and JP2009-109831; JP2012-155308A, JP2014-26261A Photoalignable polyorganosiloxane composite materials described in JP-A-2014-123091 and JP-A-2015-26050; cinnamic acid group-containing cellulose ester materials described in JP-A-2012-234146; No.
• a photo-alignment film using a photoisomerization reaction of an azo group or a photo-alignment film using a photoreaction of a cinnamate compound is preferable.
• the composition for forming an alignment film may contain a crosslinking agent, a binder, a plasticizer, a sensitizer, a crosslinking catalyst, an adhesion adjusting agent, a leveling agent, and the like, if necessary.
• the thickness of the alignment film is not particularly limited and can be appropriately selected according to the purpose.
• the thickness is preferably 10 to 1000 nm, more preferably 10 to 300 nm.
• the surface roughness of the alignment film is as described above.
• the laminate may further include other layers as necessary. Examples include a smoothing layer, an easy adhesion layer, an easy release layer, a light shielding layer, a colored layer, a fluorescent layer, an oxygen barrier layer, and a water vapor barrier layer.
• a layer having one or more functions of such a layer is collectively referred to as an intermediate layer.
• the intermediate layer may be a layer having a function other than the functions described above.
• the intermediate layer is provided, for example, between the support and the optically anisotropic layer and / or between the support and the alignment film described above, and various functions can be exhibited.
• the optically anisotropic layer produced by the production method of the present invention is preferably incorporated into a polarizing plate.
• the laminate is preferably a polarizing plate.
• the polarizing plate has at least an optically anisotropic layer and a polarizer manufactured by the manufacturing method of the present invention.
• the polarizing plate may be a circularly polarizing plate.
• a polarizer will not be specifically limited if it is a member which has the function to convert light into specific linearly polarized light,
• a conventionally well-known absorption type polarizer and reflection type polarizer can be utilized.
• the absorption polarizer an iodine polarizer, a dye polarizer using a dichroic dye, a polyene polarizer, or the like is used.
• Iodine polarizers and dye polarizers include coating polarizers and stretchable polarizers, both of which can be applied. Polarized light produced by adsorbing iodine or dichroic dye to polyvinyl alcohol and stretching. A child is preferred.
• Patent No. 5048120, Patent No. 5143918, Patent No. 5048120, Patent No. No. 4691205, Japanese Patent No. 4751481, Japanese Patent No. 4751486, and the like and known techniques relating to these polarizers can also be preferably used.
• the reflective polarizer a polarizer in which thin films having different birefringence are laminated, a wire grid polarizer, a polarizer in which a cholesteric liquid crystal having a selective reflection region and a quarter wavelength plate are combined, or the like is used.
• the thickness of the polarizer is not particularly limited, but is preferably 3 to 60 ⁇ m, more preferably 5 to 30 ⁇ m, and further preferably 5 to 15 ⁇ m.
• the polarizing plate preferably has two or more optically anisotropic layers.
• at least one of the two or more optically anisotropic layers of the polarizer may be an optically anisotropic layer produced by the production method of the present invention, and the other optical anisotropic
• the optical layer may be an optically anisotropic layer (also referred to as “other optically anisotropic layer”) manufactured by a method other than the manufacturing method of the present invention.
• the polarizing plate preferably has a positive A plate and a positive C plate.
• the positive A plate is preferably an optically anisotropic layer manufactured by the manufacturing method of the present invention
• the positive C plate is an optically anisotropic layer manufactured by the manufacturing method of the present invention or another optical layer.
• An anisotropic layer is preferred.
• the polarizing plate having the positive A plate and the positive C plate may further have another optically anisotropic layer.
• the optically anisotropic layer may be disposed directly on the polarizer by applying a polymerizable liquid crystal composition on the polarizer. Further, for example, the polarizer and the optically anisotropic layer may be bonded via one or more other layers (such as an adhesive layer or other optically anisotropic layer).
• the optically anisotropic layer produced by the production method of the present invention may be used for an image display device.
• the optically anisotropic layer may be used in a form incorporated in the polarizing plate.
• the display element used in the image display device is not particularly limited, and examples thereof include a liquid crystal cell, an organic electroluminescence (hereinafter abbreviated as “EL”) panel, a plasma display panel, and the like. Among these, a liquid crystal cell or an organic EL display panel is preferable. That is, as the image display device, a liquid crystal display device using a liquid crystal cell as a display element or an organic EL display device using an organic EL panel as a display element is preferable.
• liquid crystal display device which is an example of the image display device
• a liquid crystal display device including the above-described polarizing plate and a liquid crystal cell is preferable.
• the liquid crystal cell include a VA (Virtual Alignment) mode, an OCB (Optical Compensated Bend) mode, an IPS (In-Placed Switching) mode, and a TN (Twisted Nematic). Other methods may also be used.
• the polarizing plate is preferably used as the polarizing plate on the front side, and the polarizing plate is used as the polarizing plate on the front side and the rear side. Is more preferable.
• the organic EL display device which is an example of the image display device is preferably an organic EL display device including an organic EL display panel and a circularly polarizing plate disposed on the organic EL display panel.
• the circularly polarizing plate used here is one form of the polarizing plate described above. By having the circularly polarizing plate, it is possible to suppress a phenomenon in which external light is reflected by the electrodes of the organic EL panel and the like and lower the display contrast, thereby enabling high-quality display.
• the organic EL panel known configurations can be widely used. Further, a touch panel may be provided.
• outer layer cellulose acylate dope 10 parts by weight of the following matting agent solution was added to 90 parts by weight of the above core layer cellulose acylate dope to prepare a cellulose acetate solution used as an outer layer cellulose acylate dope.
• Matting agent solution ------------------------------------------------------------------------------------------ Silica particles having an average particle size of 20 nm (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) 2 parts by mass Methylene chloride (first solvent) 76 parts by mass Methanol (second solvent) 11 parts by mass
• the above core layer cellulose acylate dope 1 mass Part --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
• the core layer cellulose acylate dope and the outer layer cellulose acylate dope are filtered through a filter paper having an average pore size of 34 ⁇ m and a sintered metal filter having an average pore size of 10 ⁇ m, and then the core layer cellulose acylate dope and the outer layer cellulose acylate dope on both sides thereof.
• 3 layers were simultaneously cast on a drum at 20 ° C. from a casting port (band casting machine).
• the film was peeled off at a solvent content of about 20% by mass, both ends in the width direction of the film were fixed with tenter clips, and dried while being stretched in the transverse direction at a stretch ratio of 1.1.
• the obtained film was further dried by conveying between rolls of a heat treatment apparatus to produce an optical film having a thickness of 40 ⁇ m, which was designated as cellulose acylate film 1.
• the core layer of the cellulose acylate film 1 had a thickness of 36 ⁇ m, and the outer layers disposed on both sides of the core layer had a thickness of 2 ⁇ m.
• the in-plane retardation of the obtained cellulose acylate film 1 at a wavelength of 550 nm was 0 nm.
• the obtained cellulose acylate film 1 was used as a temporary support for formation.
• the following coating liquid for forming a photo-alignment film was applied with a # 2 wire bar on the surface of the cellulose acylate film 1 as a temporary support for formation, and dried with 60 ° C. hot air for 60 seconds to prepare a coating film. .
• a 750 mW / cm 2 ultra-high pressure mercury lamp (UL750, manufactured by HOYA CANDEO OPTRONICS Co., Ltd.)
• the produced coating film was irradiated with ultraviolet rays vertically in the air.
• the illuminance of the ultraviolet rays was 5 mW / cm 2 in the UV-A region (integration of wavelengths 320 to 380 nm), and the irradiation amount was 50 mJ / cm 2 in the UV-A region.
• the polymerizable liquid crystal composition A was applied on the photo-alignment film using a spin coater to form an uncured layer (layer forming step).
• the number of rotations was adjusted between 1000 and 5000 rpm so as to obtain a desired thickness.
• the uncured layer was heated to 80 ° C. (first heating temperature) using a hot plate to form a nematic phase, and maintained at that temperature for 10 seconds (first heating holding time) (nematic phase formation) Process).
• first heating holding time first heating holding time
• the uncured layer was cooled from the first heating temperature to 65 ° C. (cooling temperature) at a temperature drop rate of 40 ° C./min to form a smectic phase (cooling step).
• the cooling holding time was set to 10 seconds and held at that temperature.
• an uncured layer at 65 ° C. is 30 mJ / cm 2 (integrated exposure amount of wavelength 300 to 390 nm) using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) in a nitrogen atmosphere.
• the semi-cured layer was heated to 120 ° C. (second heating temperature) at an average temperature rising rate of 100 ° C./min using a hot plate, and the second heating temperature was further increased.
• Comparative Examples 1 to 5 production of optically anisotropic layers A-2 to A-24
• films A-2 to A-24 including optically anisotropic layers A-2 to A-24 (films respectively) 2 to 24) were produced.
• Comparative Example 1 the production of the optically anisotropic layer was completed by the first exposure process.
• Comparative Example 2 exposure was performed immediately after the nematic phase forming step without passing through the cooling step to complete the production of the optically anisotropic layer.
• Table 1 shows the thickness, Re (550), Rth (550), and Re (450) / Re (550) of the obtained optically anisotropic layer.
• the polymerizable liquid crystal composition B was applied on the photo-alignment film using a spin coater to form an uncured layer (layer forming step).
• film A-25 (including optically anisotropic layer A-25) was prepared in accordance with the production procedure of film 1 except that the conditions of each procedure were changed as shown in Table 1 shown below. Film 25) was produced.
• Table 1 shows the thickness, Re (550), Rth (550), and Re (450) / Re (550) of the obtained optically anisotropic layer.
• the phase difference values of the positive C plate C-1 and the positive C plate C-2 were adjusted by adjusting the thickness.
• TD80UL manufactured by FUJIFILM Corporation
• alkali saponification treatment The surface of TD80UL (manufactured by FUJIFILM Corporation) as a support was subjected to alkali saponification treatment. Specifically, the support was immersed in an aqueous 1.5 N sodium hydroxide solution at 55 ° C. for 2 minutes, and the taken-out support was washed in a water bath at room temperature and 0.1 N sulfuric acid at 30 ° C. Was neutralized. Thereafter, the obtained support was washed again in a room temperature water tub and further dried with hot air at 100 ° C.
• a rolled polyvinyl alcohol film having a thickness of 80 ⁇ m was continuously stretched 5 times in an iodine aqueous solution, and the stretched film was dried to obtain a polarizer having a thickness of 20 ⁇ m.
• the obtained polarizer and a support (TD80UL) subjected to alkali saponification treatment were bonded together to obtain a polarizing plate 0 with the polarizer exposed on one side.
• the polarizing plate 0 and the film 1 were bonded using an adhesive so that the polarizer of the polarizing plate 0 and the optically anisotropic layer A-1 were opposed to each other.
• the absorption axis of the polarizer and the slow axis of the optically anisotropic layer A-1 were orthogonal to each other.
• the temporary support for formation and the photo-alignment film were peeled off from the laminated film 1, and only the optically anisotropic layer A-1 was transferred onto the polarizing plate.
• the transfer film 1 was bonded onto the optically anisotropic layer via an adhesive so that the optically anisotropic layer A-1 and the positive C plate C-1 were opposed to each other.
• Polarizing plates P-2 to P-25 were obtained according to the same procedure as described above, using films 2 to 25 containing optically anisotropic layers A-2 to A-25, respectively, instead of film 1.
• the polarizing plate on the viewing side was peeled off from a liquid crystal cell of iPad (registered trademark, manufactured by Apple) and used as an IPS mode liquid crystal cell. Instead of the peeled polarizing plate, the polarizing plates P-1 to P-25 prepared above were bonded to a liquid crystal cell to prepare a liquid crystal display device. At this time, when observed from a direction perpendicular to the surface of the liquid crystal cell substrate, the absorption axis of the polarizer in each of the polarizing plates P-1 to P-25 and the optical axis of the liquid crystal layer in the liquid crystal cell are perpendicular to each other. They were pasted together in the direction.
• ⁇ Panel contrast> A value obtained by averaging the maximum values of the black luminance (Cd / m 2 ) in the upward direction (azimuth angle 0 to 175 °, in increments of 5 °) and in the downward direction (azimuth angle 180 to 355 ° in increments of 5 °) (luminance max )
• luminance max luminance
• the direct fluorescent lamp backlight source, the upper polarizing plate, the sample (any one of the films A-1 to A-25 prepared above), and the lower polarizing plate are placed on each side in the order from the bottom.
• the sample and the upper polarizing plate were rotatable.
• Luminance was measured from a vertical direction by using a luminance meter (for example, BM-5A (manufactured by TOPCON)) from the light emitted from the light source and sequentially transmitted through the upper polarizing plate, the sample, and the lower polarizing plate.
• the upper polarizing plate and the lower polarizing plate each had a polarization degree of 99.995% or more.
• the upper polarizing plate was rotated in the absence of the sample, and was adjusted to the position where the luminance was darkest (crossed Nicol state). The sample was inserted, and the sample was rotated under crossed Nicols to measure the minimum brightness. Next, two polarizing plates, an upper polarizing plate and a lower polarizing plate, were arranged in parallel Nicols, and the sample was rotated to measure the maximum luminance. In order to remove the contribution of luminance leakage due to the upper polarizing plate and the lower polarizing plate, the value obtained by the following formula is defined as the contrast of the film. The results are shown in Table 1 below.
• Contrast 1 / [ ⁇ (Minimum luminance under crossed Nicols at sample setting) / (Maximum luminance under parallel Nicol at sample setting) ⁇ - ⁇ (Minimum luminance under crossed Nicol without sample) / ( Maximum brightness under parallel Nicol without sample) ⁇ ] Based on the calculated contrast value, the film contrast was evaluated according to the following criteria. Note that the greater the contrast value, the better the film contrast.
• B Contrast is 70,000 or more and less than 100,000
• Contrast is less than 40,000
• the film 1 was bonded on a glass plate using an adhesive. Next, the temporary support for formation and the photo-alignment film were peeled from the laminated film 1 to obtain a laminated body in which glass plate / adhesive / optically anisotropic layer was laminated in this order.
• the optical anisotropy of this laminate was quantified using AxoScan OPMF-1 (manufactured by Optoscience) (Re (550) a). Further, after the same laminate was allowed to pass for 500 hours under 80 ° C. dry conditions, the optical anisotropy was quantified in the same manner as before (Re (550) b).
• phase difference change rate
• Phase difference change rate is 0.02 or less
• Phase difference change rate is 0.04 or more
• Table 1 The results are shown in Table 1.
• the column “rising temperature range” indicates the temperature difference between the semi-cured layers before and after the second heat treatment.
• the column of “temperature rise TSmN temperature difference” indicates the temperature difference between the first heating temperature and TSmN when the uncured layer is heated.
• the column “Temperature drop TSmN temperature difference” indicates the temperature difference between the cooling temperature and TSmN when the temperature of the uncured layer is lowered.
• the film contrast of the optically anisotropic layer was more excellent when the temperature decreasing rate in the cooling step was 80 ° C./min or less (more preferably 60 ° C./min or less) (Comparison of Examples 17 to 19). ).
• the difference between the temperature of the uncured layer in the first exposure process and the temperature of the semi-cured layer in the second exposure process is 40 ° C. or more, it is confirmed that the durability of the optically anisotropic layer is more excellent. (Comparison between Examples 1 and 3).
• the exposure amount in the second exposure process was 200 mJ / cm 2 or more, it was confirmed that the durability of the optically anisotropic layer was more excellent (comparison with Examples 6 and 7).
• the surface of the positive C plate C-2 is bonded onto the surface of the optically anisotropic layer using an adhesive, and then the forming temporary support is peeled off from the polarizing plate, and the support / polarization
• a circularly polarizing plate CP-1 was obtained in which the optical element / adhesive / optically anisotropic layer / adhesive / positive C plate C-2 was laminated in this order.
• the results are shown in Table 2.
• the column of “frontal reflection” in the table indicates the evaluation result of the reflection color when visually observed from the front.
• the column of “45 ° reflection” indicates the evaluation result of the reflection color when observed by visual observation from the polar angle of 45 °.
• the optically anisotropic layer obtained by the production method of the present invention can be preferably used in an organic EL display device.

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