Retardation film, polarizing plate, and image display device

Abstract

The present invention addresses the problem of providing a retardation film with which it is possible to produce an image display device in which implementation irregularities are suppressed, as well as a polarizing plate and image display device in which said retardation film is used. A retardation film according to the present invention has: a supporting body with which in-plane retardation exhibits inverse wavelength dispersion; and a liquid crystal layer directly laminated on the supporting body. The supporting body is a polymer film which has undergone a stretching treatment in at least one in-plane direction. The liquid crystal layer is a positive C-plate formed by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound. In addition, the photoelastic constant of the supporting body is 30×10-12 Pa or less.

Description

Phase difference film, polarizing plate and image display device

[0001] The present invention relates to a retardation film, a polarizing plate, and an image display device.

[0002] Conventionally, polarizing plates having a retardation film and a polarizer have been used in liquid crystal displays, organic electroluminescent devices, etc. for the purpose of optical compensation, antireflection, etc. Patent Document 1, for example, describes a retardation film in such a polarizing plate as "a retardation film comprising a support and a liquid crystal layer formed in contact with the support using a liquid crystal composition containing a liquid crystal compound, wherein the surface energy of the support surface on which the liquid crystal layer is formed is 45 mN / m or more and the nonpolar dispersion force component contained in the surface energy is 45 mN / m or more, the liquid crystal compound is fixed in an aligned state, and the contrast is greater than 10,000" ([Claim 1]).

[0003] International Publication No. 2020 / 045224

[0004] The present inventors have studied the retardation film described in Patent Document 1 and have found that when an image display device manufactured using the retardation film is set to black display and observed from an oblique direction, light leakage and color unevenness (hereinafter, collectively referred to as "mounting unevenness") may occur depending on the observation direction.

[0005] Therefore, an object of the present invention is to provide a retardation film that enables the production of an image display device in which the occurrence of mounting unevenness is suppressed, and a polarizing plate and an image display device that use the retardation film.

[0006] As a result of extensive research into the above-mentioned problems, the present inventors have found that the in-plane retardation exhibits reverse wavelength dispersion and the photoelastic constant is 30×10 －１２ Pa or less, or the product of the photoelastic constant and the thickness is 2000 × 10 －１２The inventors have found that an image display device in which the occurrence of mounting unevenness is suppressed can be manufactured by using a retardation film having a support made of a polymer film with a viscosity of Pa μm or less and a liquid crystal layer (positive C plate) directly laminated on the support, and have completed the present invention. That is, the inventors have found that the above-mentioned problem can be solved by the following configuration.

[0007] [1] A retardation film having a support whose in-plane retardation exhibits reverse wavelength dispersion and a liquid crystal layer directly laminated on the support, wherein the support is a polymer film stretched in at least one direction in the plane, the liquid crystal layer is a positive C plate formed by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound, and the photoelastic constant of the support is 30×10 －１２ [2] The retardation film according to [1], wherein the difference between the solubility parameter of the polymer contained in the polymer film and the solubility parameter of the liquid crystal compound contained in the liquid crystal composition at the largest content is 8.8 or more. [3] The retardation film according to [1] or [2], wherein the polymer contained in the polymer film is polycarbonate or polyester. [4] The photoelastic constant of the support is 25×10 －１２The retardation film according to any one of [1] to [3], wherein the difference between the solubility parameter of the polymer contained in the polymer film and the solubility parameter of the liquid crystal compound contained in the liquid crystal composition at the largest content is 9.5 or more. [5] The retardation film according to any one of [1] to [4], wherein the difference between the solubility parameter of the polymer contained in the polymer film and the solubility parameter of the liquid crystal compound contained in the liquid crystal composition at the largest content is 9.5 or more. [6] The retardation film according to any one of [1] to [5], wherein the support is a positive A plate. [7] The retardation film according to any one of [1] to [6], wherein the retardation in the thickness direction of the liquid crystal layer exhibits reverse wavelength dispersion. [8] The retardation film according to any one of [1] to [7], wherein the liquid crystal composition further contains a boronic acid monomer having a polymerizable group and a boronic acid group represented by formula (B) described later. [9] The retardation film according to any one of [1] to [8], wherein the polymer contained in the polymer film satisfies formula (1) described later.

[10] A retardation film having a support whose in-plane retardation exhibits reverse wavelength dispersion and a liquid crystal layer directly laminated on the support, wherein the support is a polymer film stretched in at least one direction in the plane, the liquid crystal layer is a positive C plate obtained by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound, and the product of the photoelastic constant (unit: Pa) and the thickness (unit: μm) of the support is 2000×10 －１２ A retardation film having a viscosity of Pa·μm or less.

[11] A polarizing plate comprising the retardation film according to any one of [1] to

[10] and a polarizer.

[12] The polarizing plate according to

[11] , wherein the absorption axis of the polarizer and the slow axis of the support of the retardation film are perpendicular or parallel to each other.

[13] The polarizing plate according to

[11] , wherein the absorption axis of the polarizer and the slow axis of the support of the retardation film are parallel to each other.

[14] An image display device comprising the polarizing plate according to any one of

[11] to

[13] .

[0008] As will be described below, according to the present invention, it is possible to provide a retardation film that can be used to fabricate an image display device in which the occurrence of mounting unevenness is suppressed, and a polarizing plate and an image display device using the retardation film.

[0009] The present invention will be described in detail below. The following description of the constituent elements may be based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the upper and lower limits. In this specification, the upper or lower limit of a numerical range described in a stepwise manner may be replaced with the upper or lower limit of another stepwise manner. In this specification, the upper or lower limit of a numerical range described in a stepwise manner may be replaced with a value shown in the Examples. In this specification, each component may be a single substance corresponding to the component, or two or more substances may be used in combination. When two or more substances are used in combination for each component, the content of that component refers to the total content of the substances used in combination, unless otherwise specified. In addition, in this specification, "perpendicular" and "parallel" with respect to angles mean a range of ±10° of the exact angle, and "same" and "different" with respect to angles can be determined based on whether the difference is less than 5°. In addition, in this specification, "visible light" refers to 380 to 780 nm. In addition, in this specification, unless otherwise specified, the measurement wavelength is 550 nm. In addition, the bonding direction of divalent groups (e.g., -O-CO-) described in this specification is not particularly limited, and for example, "L １ -L ２ -L ３ In the bond ２ When is —O—CO—, L １ The position where it is bonded to the side is *1, L ３ If the position bonded to the side is *2, then L ２ may be *1-O-CO-*2 or *1-CO-O-*2. Next, the terms used in this specification will be explained.

[0010] [Slow Axis] In this specification, the term "slow axis" refers to the direction in which the refractive index is maximum in the plane. The slow axis of a retardation film refers to the slow axis of the entire retardation film.

[0011] [Re(λ), Rth(λ)] In this specification, Re(λ) and Rth(λ) represent the in-plane retardation and the retardation in the thickness direction, respectively, at a wavelength λ. Unless otherwise specified, the wavelength λ is 550 nm. In this specification, Re(λ) and Rth(λ) are values ​​measured at a wavelength λ using an AxoScan OPMF-1 (manufactured by OptoScience). Specifically, by inputting the average refractive index ((nx+ny+nz) / 3) and film thickness (d (μm)) into the AxoScan OPMF-1, the following slow axis direction (°) Re(λ) = R0(λ) Rth(λ) = ((nx+ny) / 2-nz)×d is calculated. Note that R0(λ) is displayed as a numerical value calculated by AxoScan OPMF-1, but it means Re(λ).

[0012] [Substituent] In this specification, examples of the substituent (monovalent substituent) include the substituents described below in Substituent Group A. In this specification, the phrase "optionally having a substituent" includes not only an embodiment in which no substituent is present, but also an embodiment in which one or more substituents are present. <Substituent Group A> Examples of the substituent include halogen atoms (for example, fluorine atoms, chlorine atoms, and bromine atoms, preferably chlorine atoms and fluorine atoms, and more preferably fluorine atoms); alkyl groups (preferably linear, branched, or cyclic alkyl groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, and particularly preferably 1 to 8 carbon atoms, such as linear alkyl groups having 1 to 6 carbon atoms (for example, methyl, ethyl, n-propyl, n-butyl, n-pentyl, and n-hexyl), branched alkyl groups having 3 to 6 carbon atoms (for example, isopropyl, isobutyl, tert-butyl, sec-butyl, neopentyl, isohexyl, and 3-methylpentyl), and cyclic alkyl groups having 3 to 12 carbon atoms (for example, cyclopropyl, cyclopentyl, cyclohexyl, 1-norbornyl, and 1-adamantyl)); alkenyl groups (preferably alkenyl groups having 2 to 48 carbon atoms, more preferably 2 to 18 carbon atoms, such as vinyl groups, allyl groups, 1-butenyl groups, and 2-butenyl groups); alkynyl groups (preferably alkynyl groups having 2 to 6 carbon atoms, more preferably 2 to 4 carbon atoms, such as ethynyl groups, 1-propynyl groups, propargyl groups, 1-butynyl groups, and 2-butynyl groups); aryl groups (preferably aryl groups having 6 to 48 carbon atoms, more preferably 6 to 24 carbon atoms, such as phenyl groups, oligoaryl groups (naphthyl groups, anthryl groups), phenanthrenyl groups, fluorenyl groups, pyrenyl groups, triphenylenyl groups, and biphenyl groups); Heteroaryl groups (preferably heterocyclic groups having 1 to 32 carbon atoms, more preferably 1 to 18 carbon atoms, such as a 2-thienyl group, a 4-pyridyl group, a 2-furyl group, a 2-pyrimidinyl group, a 1-pyridyl group, a 2-benzothiazolyl group, a 1-imidazolyl group, a 1-pyrazolyl group, or a benzotriazol-1-yl group);arylalkyl groups (preferably arylalkyl groups having 7 to 15 carbon atoms, for example, benzyl group, phenethyl group, methylbenzyl group, phenylpropyl group, 1-methylphenylethyl group, phenylbutyl group, 2-methylphenylpropyl group, tetrahydronaphthyl group, naphthylmethyl group, naphthylethyl group, indenyl group, fluorenyl group, anthracenylmethyl group (anthrylmethyl group), phenanthrenylmethyl group (phenanthrylmethyl group)); silyl groups (preferably silyl groups having 3 to 38 carbon atoms, more preferably 3 to 18 carbon atoms, for example, trimethylsilyl group, triethylsilyl group, tributylsilyl group, t-butyldimethylsilyl group, t-hexyldimethylsilyl group); hydroxy groups; cyano groups; nitro groups; morpholino groups; Alkoxy groups (preferably alkoxy groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, for example, methoxy, ethoxy, 1-butoxy, 2-butoxy, isopropoxy, t-butoxy, dodecyloxy, and cycloalkyloxy groups (for example, cyclopentyloxy and cyclohexyloxy)); aryloxy groups (preferably aryloxy groups having 6 to 48 carbon atoms, more preferably 6 to 24 carbon atoms, for example, phenoxy and 1-naphthoxy); alkenyloxy groups (preferably alkenyloxy groups having 2 to 6 carbon atoms, for example, vinyloxy, 1-propenyloxy, 2-n-propenyloxy (allyloxy), 1-n-butenyloxy, and prenyloxy); heterocyclic oxy groups (preferably heterocyclic oxy groups having 1 to 32 carbon atoms, more preferably 1 to 18 carbon atoms, such as a 1-phenyltetrazole-5-oxy group or a 2-tetrahydropyranyloxy group); silyloxy groups (preferably silyloxy groups having 1 to 32 carbon atoms, more preferably 1 to 18 carbon atoms, such as a trimethylsilyloxy group, a t-butyldimethylsilyloxy group or a diphenylmethylsilyloxy group); acyloxy groups (preferably acyloxy groups having 2 to 48 carbon atoms, more preferably 2 to 24 carbon atoms, such as an acetoxy group, a pivaloyloxy group, a benzoyloxy group, a dodecanoyloxy group, an acryloyloxy group or a methacryloyloxy group);hydroxyalkyleneoxy groups (preferably hydroxyalkyleneoxy groups having 2 to 10 carbon atoms, for example, a hydroxyethyleneoxy group); alkoxycarbonyloxy groups (preferably alkoxycarbonyloxy groups having 2 to 48 carbon atoms, more preferably 2 to 24 carbon atoms, for example, an ethoxycarbonyloxy group, a t-butoxycarbonyloxy group, or a cycloalkyloxycarbonyloxy group (for example, a cyclohexyloxycarbonyloxy group)); aryloxycarbonyloxy groups (preferably aryloxycarbonyloxy groups having 7 to 32 carbon atoms, more preferably 7 to 24 carbon atoms, for example, a phenoxycarbonyloxy group); carbamoyloxy groups (preferably carbamoyloxy groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, for example, an N,N-dimethylcarbamoyloxy group, an N-butylcarbamoyloxy group, an N-phenylcarbamoyloxy group, or an N-ethyl-N-phenylcarbamoyloxy group); sulfamoyloxy groups (preferably sulfamoyloxy groups having 1 to 32 carbon atoms, more preferably 1 to 24 carbon atoms, such as an N,N-diethylsulfamoyloxy group or an N-propylsulfamoyloxy group); alkylsulfonyloxy groups (preferably alkylsulfonyloxy groups having 1 to 38 carbon atoms, more preferably 1 to 24 carbon atoms, such as a methylsulfonyloxy group, a hexadecylsulfonyloxy group or a cyclohexylsulfonyloxy group); arylsulfonyloxy groups (preferably arylsulfonyloxy groups having 6 to 32 carbon atoms, more preferably 6 to 24 carbon atoms, such as a phenylsulfonyloxy group); acyl groups (preferably acyl groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, such as a formyl group, an acetyl group, an acryloyl group, a methacryloyl group, a pivaloyl group, a benzoyl group, a tetradecanoyl group or a cyclohexanoyl group); an alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 48 carbon atoms, more preferably 2 to 24 carbon atoms, for example, a methoxycarbonyl group, an ethoxycarbonyl group, an octadecyloxycarbonyl group, a cyclohexyloxycarbonyl group, or a 2,6-di-tert-butyl-4-methylcyclohexyloxycarbonyl group);an aryloxycarbonyl group (preferably an aryloxycarbonyl group having 7 to 32 carbon atoms, more preferably 7 to 24 carbon atoms, such as a phenoxycarbonyl group); a carbamoyl group (preferably a carbamoyl group having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, such as a carbamoyl group, N,N-diethylcarbamoyl group, N-ethyl-N-octylcarbamoyl group, N,N-dibutylcarbamoyl group, N-propylcarbamoyl group, N-phenylcarbamoyl group, N-methyl-N-phenylcarbamoyl group, or N,N-dicyclohexylcarbamoyl group); an amino group (preferably an amino group having 32 or less carbon atoms, more preferably 24 or less carbon atoms, such as an amino group, methylamino group, N,N-dimethylamino group, N,N-dibutylamino group, tetradecylamino group, 2-ethylhexylamino group, or cyclohexylamino group); anilino group (preferably an anilino group having 6 to 32 carbon atoms, more preferably 6 to 24 carbon atoms, for example, an anilino group, an N-methylanilino group); heterocyclic amino group (preferably a heterocyclic amino group having 1 to 32 carbon atoms, more preferably 1 to 18 carbon atoms, for example, a 4-pyridylamino group); carbonamido group (preferably a carbonamido group having 2 to 48 carbon atoms, more preferably 2 to 24 carbon atoms, for example, an acetamido group, a benzamido group, a tetradecanamido group, a pivaloylamido group, a cyclohexanamido group); ureido group (preferably a ureido group having 1 to 32 carbon atoms, more preferably 1 to 24 carbon atoms, for example, a ureido group, an N,N-dimethylureido group, an N-phenylureido group); imido group (preferably an imido group having 36 or less carbon atoms, more preferably 24 or less carbon atoms, for example, an N-succinimido group, an N-phthalimido group); an alkoxycarbonylamino group (preferably an alkoxycarbonylamino group having 2 to 48 carbon atoms, more preferably 2 to 24 carbon atoms, for example, a methoxycarbonylamino group, an ethoxycarbonylamino group, a t-butoxycarbonylamino group, an octadecyloxycarbonylamino group, or a cyclohexyloxycarbonylamino group); an aryloxycarbonylamino group (preferably an aryloxycarbonylamino group having 7 to 32 carbon atoms, more preferably 7 to 24 carbon atoms, for example, a phenoxycarbonylamino group);sulfonamido groups (preferably sulfonamido groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, for example, methanesulfonamido groups, butanesulfonamido groups, benzenesulfonamido groups, hexadecanesulfonamido groups, and cyclohexanesulfonamido groups); sulfamoylamino groups (preferably sulfamoylamino groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, for example, N,N-dipropylsulfamoylamino groups, and N-ethyl-N-dodecylsulfamoylamino groups); azo groups (preferably azo groups having 1 to 32 carbon atoms, more preferably 1 to 24 carbon atoms, for example, phenylazo groups and 3-pyrazolylazo groups); alkylthio groups (preferably alkylthio groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, for example, methylthio groups, ethylthio groups, octylthio groups, and cyclohexylthio groups); an arylthio group (preferably an arylthio group having 6 to 48 carbon atoms, more preferably an arylthio group having 6 to 24 carbon atoms, for example, a phenylthio group); a heterocyclic thio group (preferably a heterocyclic thio group having 1 to 32 carbon atoms, more preferably a heterocyclic thio group having 1 to 18 carbon atoms, for example, a 2-benzothiazolylthio group, a 2-pyridylthio group, or a 1-phenyltetrazolylthio group); an alkylsulfinyl group (preferably an alkylsulfinyl group having 1 to 32 carbon atoms, more preferably an alkylsulfinyl group having 1 to 24 carbon atoms, for example, a dodecanesulfinyl group); an arylsulfinyl group (preferably an arylsulfinyl group having 6 to 32 carbon atoms, more preferably an arylsulfinyl group having 6 to 24 carbon atoms, for example, a phenylsulfinyl group); alkylsulfonyl groups (preferably alkylsulfonyl groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, for example, methylsulfonyl, ethylsulfonyl, propylsulfonyl, butylsulfonyl, isopropylsulfonyl, 2-ethylhexylsulfonyl, hexadecylsulfonyl, octylsulfonyl, and cyclohexylsulfonyl groups); arylsulfonyl groups (preferably arylsulfonyl groups having 6 to 48 carbon atoms, more preferably 6 to 24 carbon atoms, for example, phenylsulfonyl, and 1-naphthylsulfonyl groups);sulfamoyl groups (preferably sulfamoyl groups having 32 or less carbon atoms, more preferably 24 or less carbon atoms, for example, a sulfamoyl group, an N,N-dipropylsulfamoyl group, an N-ethyl-N-dodecylsulfamoyl group, an N-ethyl-N-phenylsulfamoyl group, an N-cyclohexylsulfamoyl group, or an N-(2-ethylhexyl)sulfamoyl group); phosphonyl groups (preferably phosphonyl groups having 1 to 32 carbon atoms, more preferably 1 to 24 carbon atoms, for example, a phenoxyphosphonyl group, an octyloxyphosphonyl group, or a phenylphosphonyl group); phosphinoylamino groups (preferably phosphinoylamino groups having 1 to 32 carbon atoms, more preferably 1 to 24 carbon atoms, for example, a diethoxyphosphinoylamino group, or a dioctyloxyphosphinoylamino group); epoxy groups; —NHCOCH; ３ ;-SO ２ NHC ２ H ４ OCH ３ ;-NHSO ２ CH ３ and the like, and two or more of these may be combined. These substituents may be further substituted with other substituents. When two or more substituents are present, they may be the same or different. If possible, they may be bonded to each other to form a ring.

[0013] [Retardation Film] The retardation film of the present invention is a retardation film having a support whose in-plane retardation exhibits reverse wavelength dispersion and a liquid crystal layer directly laminated on the support. The support of the retardation film of the present invention is a polymer film that has been stretched in at least one direction in the plane. The liquid crystal layer of the retardation film of the present invention is a positive C plate obtained by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound. The retardation film of the present invention is a retardation film having a support whose photoelastic constant is 30×10 －１２ Pa or less, or the product of the photoelastic constant (unit: Pa) and the thickness (unit: μm) of the support is 2000×10 －１２ It is Pa·μm or less.

[0014] In the present invention, as described above, the in-plane retardation exhibits reverse wavelength dispersion and the photoelastic constant is 30×10 －１２ Pa or less, or the product of the photoelastic constant and the thickness is 2000 × 10 －１２ By using a retardation film having a polymer film support with a viscosity of 100 Pa·μm or less and a liquid crystal layer (positive C plate) directly laminated on the support, an image display device in which the occurrence of mounting unevenness is suppressed can be produced. The mechanism is not clear in detail, but is presumed to be roughly as follows. First, the retardation film needs to be bonded to a display element when incorporated into an image display device. The inventors speculate that the cause of mounting unevenness occurs when the retardation film and the display element are bonded together. Based on the results of Comparative Example 4 of the present specification, i.e., an example corresponding to Example 1 of Patent Document 1 mentioned above, the inventors speculate that the cause of mounting unevenness is due to the occurrence of an unintended region of phase difference change within the plane of the support due to uneven stress that inevitably occurs within the plane of the support when the retardation film and the display element are bonded together. Therefore, in the present invention, a retardation film having a photoelastic constant of 30×10 －１２ Pa or less, or the product of the photoelastic constant and the thickness is 2000 × 10 －１２ By using a support with a viscosity of Pa·μm or less, it is thought that a phase difference is less likely to occur due to the stress generated in the plane during bonding, making it possible to produce an image display device in which the occurrence of mounting unevenness is suppressed.

[0015] The thickness of the retardation film of the present invention is preferably 2 to 210 μm, more preferably 3 to 110 μm, and further preferably 5 to 80 μm. When the retardation film has a plurality of layers, the thickness of the retardation film refers to the total thickness including the layers.

[0016] [Support] The support of the retardation film of the present invention is a support whose in-plane retardation exhibits reverse wavelength dispersion. Here, "in-plane retardation exhibits reverse wavelength dispersion" means that when the in-plane retardation (Re) value of a layer (film) is measured at a specific wavelength (visible light range), the Re value increases as the measured wavelength increases, and in the present invention, this means that the relationship Re(450) / Re(550)<1.00 is satisfied. Furthermore, the support preferably has Re(450) / Re(550) of 0.60 or more and 1.00 or less, more preferably 0.70 or more and 1.00 or less, and even more preferably 0.75 or more and 0.95 or less. Furthermore, the in-plane retardation of the support preferably satisfies the relationship Re(650) / Re(550)>1.00. Re(650) / Re(550) is preferably 1.00 or more and 1.30 or less, more preferably 1.00 or more and 1.25 or less, and even more preferably 1.00 or more and 1.20 or less.

[0017] In addition, the support of the retardation film of the present invention is a polymer film that has been stretched in at least one direction in the plane, and is preferably a polymer film that has been stretched uniaxially or biaxially.The polymers contained in such polymer films include polycarbonate; polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyarylene sulfides such as polyphenylene sulfide; polyvinyl alcohol; polyarylate; cellulose ester polymers such as cellulose acylate; polyethersulfone; polysulfone; polyallylsulfone; polyvinyl chloride; cyclic olefin polymers such as norbornene polymers; etc. Among these, polycarbonate or polyester is preferred because the orientation of the retardation film is improved and the adhesion between the support and the liquid crystal layer is improved.In addition, the support of the retardation film of the present invention is also preferably a resin that contains a resin that exhibits positive birefringence and a resin that exhibits negative birefringence. Examples of these resins include the resins described in JP 2023-180135 A or JP 2023-180201 A. Specific examples of resins that exhibit positive birefringence include cellulose-based resins, such as those described in paragraphs

[0023] to

[0029] of JP 2023-180135 A or paragraphs

[0032] to

[0037] of JP 2023-180201 A. Specific examples of resins that exhibit negative birefringence include ester-based resins, such as those described in paragraphs

[0030] to

[0043] of JP 2023-180135 A or paragraphs

[0038] to

[0051] of JP 2023-180201 A.

[0018] The support of the retardation film of the present invention has a photoelastic constant of 30×10 －１２ Pa or less, or the product of the photoelastic constant and the thickness is 2000 × 10 －１２Pa μm or less. Here, the photoelastic constant refers to the rate of change in retardation with respect to stress, and the photoelastic constant of the support can be measured by cutting a test piece 50 mm long and 10 mm wide from the support and using a spectroscopic ellipsometer (for example, Spectroellipsometer M-220 manufactured by JASCO Corporation). The photoelastic constant is measured in an environment of 25 ° C. and 60% humidity, and if there is dependence on the measurement orientation (slow axis / fast axis) of the film, the average value is adopted. The thickness of the support is calculated as the average value of any five points measured by cross-sectional observation using an optical microscope.

[0019] In the present invention, the photoelastic constant of the support is set to 25×10 because an image display device in which the occurrence of mounting unevenness can be further suppressed can be produced. －１２ Pa or less, and －１２ Pa or more 25×10 －１２ Pa or less, and more preferably 1×10 －１２ Pa or more 22×10 －１２ It is more preferable that the range is 1×10 Pa or less. －１２ Pa or more 20×10 －１２ It is particularly preferable that the range is 0.1 Pa or less.

[0020] In the present invention, the product of the photoelastic constant (unit: Pa) and the thickness (unit: μm) of the support can be set to 1800×10 －１２ It is preferable that the density is less than 1500×10 Pa·μm. －１２ It is more preferable that the value is equal to or less than Pa·μm. The lower limit of this product is not particularly limited, but is preferably 10×10 －１２ It is preferable that the density is 20×10 Pa·μm or more. －１２ More preferably, it is 30×10 Pa·μm or more. －１２ It is more preferable that the viscosity is Pa·μm or more.

[0021] In the present invention, the support is preferably a positive A plate because oblique light leakage is suppressed when the film is used in an image display device. In this specification, a positive A plate is defined as follows. Specifically, a positive A plate satisfies the relationship of formula (A1), where nx is the refractive index in the slow axis direction (the direction in which the in-plane refractive index is maximum) of the film, ny is the refractive index in the direction perpendicular to the in-plane slow axis, and nz is the refractive index in the thickness direction. A positive A plate exhibits a positive Rth. Formula (A1) nx>ny≒nz. The above "≒" encompasses not only cases where the two are completely identical, but also cases where the two are substantially identical. "Substantially identical" also includes, for example, cases where (ny-nz)×d (where d is the film thickness) is −10 to 10 nm, preferably −5 to 5 nm, in "ny≒nz." The Re(550) of the support is preferably 10 nm or more and 300 nm or less, more preferably 50 nm or more and 200 nm or less, and even more preferably 100 nm or more and 160 nm or less. The Rth(550) of the support is preferably 10 nm or more and 200 nm or less, more preferably 50 nm or more and 150 nm or less, and even more preferably 60 nm or more and 130 nm or less.

[0022] In the present invention, the support is preferably transparent. The term "transparent" as used herein refers to a visible light transmittance of 60% or more, preferably 80% or more, and more preferably 90% or more. The thickness of the support is not particularly limited, but is preferably 1 to 200 μm, and more preferably 2 to 100 μm.

[0023] [Liquid Crystal Layer] The liquid crystal layer of the retardation film of the present invention is a liquid crystal layer directly laminated on the support, i.e., no other member (for example, a so-called alignment film) exists between the support and the liquid crystal layer.

[0024] The liquid crystal layer of the retardation film of the present invention is a positive C plate obtained by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound. Here, since the liquid crystal layer fixes the alignment state of the liquid crystal composition as described above, the liquid crystal compound contained in the liquid crystal layer no longer needs to exhibit liquid crystallinity. In this specification, the positive C plate is defined as follows. Specifically, a positive C plate (positive C plate) satisfies the relationship of formula (C1), where nx is the refractive index in the in-plane slow axis direction (the direction in which the in-plane refractive index is maximum) of the liquid crystal layer, ny is the refractive index in the direction perpendicular to the in-plane slow axis, and nz is the refractive index in the thickness direction. The positive C plate exhibits a negative Rth. Formula (C1) nx ≒ ny < nz. The above "≒" encompasses not only the case where the two are completely identical, but also the case where the two are substantially identical. "Substantially the same" means that, for example, "nx ≒ ny" also includes a case where (nx - ny) x d (where d is the film thickness) is 0 to 10 nm, preferably 0 to 5 nm. The Re(550) of the liquid crystal layer is preferably 0 nm or more and 10 nm or less, more preferably 0 nm or more and 5 nm or less, and even more preferably 0 nm or more and 2 nm or less. The Rth(550) of the liquid crystal layer is preferably -200 nm or more and -10 nm or less, more preferably -180 nm or more and -50 nm or less, and even more preferably -150 nm or more and -80 nm or less.

[0025] In the present invention, the liquid crystal layer preferably exhibits reverse wavelength dispersion because this suppresses oblique light leakage when used in an image display device. More specifically, the thickness-direction retardation preferably exhibits reverse wavelength dispersion. Here, "thickness-direction retardation exhibits reverse wavelength dispersion" refers to a state in which, when the thickness-direction retardation (Rth) value of the liquid crystal layer alone is measured at a specific wavelength (visible light range), the absolute value of the Rth value increases as the measured wavelength increases. In the present invention, this refers to a state in which the relationship Rth(450) / Rth(550)<1.00 is satisfied. Furthermore, the liquid crystal layer preferably has an Rth(450) / Rth(550) ratio of 0.60 to 1.10, more preferably 0.70 to 1.00, and even more preferably 0.75 to 0.95. Furthermore, the thickness-direction retardation of the liquid crystal layer preferably satisfies the relationship Rth(650) / Rth(550)>1.00. Rth(650) / Rth(550) is preferably 1.00 or more and 1.30 or less, more preferably 1.00 or more and 1.25 or less, and even more preferably 1.00 or more and 1.20 or less.

[0026] In the present invention, the thickness of the liquid crystal layer is not particularly limited, but is preferably 0.5 to 5 μm, more preferably 0.5 to 4 μm, and even more preferably 0.5 to 3 μm.

[0027] <Liquid Crystal Composition> As described above, the liquid crystal layer of the retardation film of the present invention is a positive C plate obtained by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound.

[0028] (Liquid Crystal Compound) The liquid crystal compound contained in the liquid crystal composition is not particularly limited, and conventionally known liquid crystal compounds can be used. Generally, liquid crystal compounds can be classified into rod-shaped and discotic types based on their shape. Each type can further be divided into low-molecular-weight and high-molecular-weight types. High-molecular-weight compounds generally refer to compounds with a degree of polymerization of 100 or more (see "Polymer Physics / Phase Transition Dynamics," by Masao Doi, page 2, Iwanami Shoten, 1992). In the present invention, rod-shaped liquid crystal compounds are preferably used. A mixture of two or more rod-shaped liquid crystal compounds may also be used. Examples of rod-shaped liquid crystal compounds that can be preferably used include, but are not limited to, those described in claim 1 of JP-A-11-513019 and paragraphs

[0026] to

[0098] of JP-A-2005-289980.

[0029] In the present invention, the liquid crystal compound preferably has a polymerizable group, more preferably two or more polymerizable groups, to improve the durability of the liquid crystal layer. Here, the polymerizable group is not particularly limited, but a polymerizable group capable of radical polymerization or cation polymerization is preferred. As the radical polymerizable group, known radical polymerizable groups can be used, and preferred examples include an acryloyloxy group or a methacryloyloxy group. In this case, the acryloyloxy group is generally known to have a faster polymerization rate, and from the viewpoint of improving productivity, an acryloyloxy group is preferred, but a methacryloyloxy group can also be used as the polymerizable group. As the cationically polymerizable group, known cationically polymerizable groups can be used, and specific examples 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. Among these, an alicyclic ether group or a vinyloxy group is preferred, and an epoxy group, an oxetanyl group, or a vinyloxy group is particularly preferred. Particularly preferred examples of the polymerizable group include polymerizable groups represented by any one of the following formulae (P-1) to (P-20).

[0030]

[0031] In the present invention, the liquid crystal compound is preferably a liquid crystal compound having reverse wavelength dispersion, and more preferably a compound represented by the following formula (A), for the reason that the orientation of the retardation film is good. １ -SP １ -D ５ - (A １ ) ａ１ -D ３ - (G １ ) ｇ１ -D １ -Ar-D ２ - (G ２ ) ｇ２ -D ４ - (A ２ ) ａ２ -D ６ -SP ２ -L ２ (A)

[0032] In the above formula (A), a1, a2, g1, and g2 each independently represent 0 or 1. However, at least one of a1 and g1 represents 1, and at least one of a2 and g2 represents 1. １ , D ２ , D ３ , D ４ , D ５ and D ６ each independently represents a single bond, or —CO—, —O—, —S—, —C(═S)—, or —CR １ R ２ -, -CR ３ =CR ４ -, -NR ５ -, or a divalent linking group formed by a combination of two or more thereof, R １ ~R ５ each independently represents a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 12 carbon atoms. １ and G ２ each independently represents an aromatic ring having 6 to 20 carbon atoms which may have a substituent, or a divalent alicyclic hydrocarbon group having 5 to 20 carbon atoms which may have a substituent, and -CH ２ One or more of - may be substituted with -O-, -S- or -NH-. １and A ２ each independently represents an aromatic ring having 6 to 20 carbon atoms which may have a substituent, or a divalent alicyclic hydrocarbon group having 5 to 20 carbon atoms which may have a substituent, and -CH ２ One or more of - may be substituted with -O-, -S- or -NH-. １ and SP ２ each independently represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, provided that —CH ２ One or more of - may be substituted with -O-, -S-, -NH-, -N(Q)- or -CO-. Q represents a substituent. １ and L ２ each independently represents a monovalent organic group; １ and L ２ At least one of the groups represented by the formula (Ar-3) below represents a polymerizable group. １ and L ２ and L in the following formula (Ar-3): ３ and L ４ At least one of the following represents a polymerizable group. Ar represents any aromatic ring selected from the group consisting of groups represented by formulas (Ar-1) to (Ar-7) described below.

[0033] In the above formula (A), a1, a2, g1, and g2 are preferably all 1 because the liquid crystal composition is more likely to exhibit a smectic liquid crystal state. In addition, it is preferable that a1 and a2 are all 0 and g1 and g2 are all 1 because the durability of the liquid crystal layer to be produced is improved.

[0034] In the above formula (A), D １ , D ２ , D ３ , D ４ , D ５ and D ６ Examples of the divalent linking group represented by one embodiment of the formula (I) include -CO-, -O-, -S-, -C(=S)-, and -CR １ R ２ -, -CR ３ =CR４ -, -NR ５ -, or a divalent linking group formed by a combination of two or more thereof. １ ~R ５ each independently represents a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 12 carbon atoms. Specific examples of the divalent linking group include -CO-, -O-, -CO-O-, -C(=S)O-, and -CR １ R ２ -, -CR １ R ２ -CR １ R ２ -, -O-CR １ R ２ -, -CR １ R ２ -O-CR １ R ２ -, -CO-O-CR １ R ２ -, -O-CO-CR １ R ２ -, -CR １ R ２ -O-CO-CR １ R ２ -, -CR １ R ２ -CO-O-CR １ R ２ -, -NR ５ -CR １ R ２ - and -CO-NR ５ -, etc. １ , R ２ and R ５ each independently represents a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 12 carbon atoms. Among these, any of —CO—, —O—, and —CO—O— is preferred.

[0035] In the above formula (A), G １ and G ２Examples of the aromatic ring having 6 to 20 carbon atoms represented by one embodiment of the formula (1) include aromatic hydrocarbon rings such as a benzene ring, a naphthalene ring, an anthracene ring, and a phenanthroline ring; and aromatic heterocycles such as a furan ring, a pyrrole ring, a thiophene ring, a pyridine ring, a thiazole ring, and a benzothiazole ring. Of these, a benzene ring (for example, a 1,4-phenyl group) is preferred.

[0036] In the above formula (A), G １ and G ２ The divalent alicyclic hydrocarbon group having 5 to 20 carbon atoms represented by one embodiment of the formula (1) is preferably a 5-membered or 6-membered ring. The alicyclic hydrocarbon group may be saturated or unsaturated, but is preferably a saturated alicyclic hydrocarbon group. １ and G ２ For the divalent alicyclic hydrocarbon group represented by the formula (I), reference can be made to, for example, paragraph

[0078] of JP-A-2012-21068, the contents of which are incorporated herein by reference.

[0037] In the present invention, the durability of the liquid crystal layer to be produced is improved by adjusting the G １ and G ２ is preferably a cycloalkane ring. Specific examples of the cycloalkane ring include a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, a cyclododecane ring, and a cyclodocosane ring. Of these, a cyclohexane ring is preferred, a 1,4-cyclohexylene group is more preferred, and a trans-1,4-cyclohexylene group is even more preferred.

[0038] In addition, in the above formula (A), G １ and G ２ With regard to the above, examples of the substituent that the aromatic ring having 6 to 20 carbon atoms or the divalent alicyclic hydrocarbon group having 5 to 20 carbon atoms may have include the substituents described in the above-mentioned substituent group A, and among them, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, or a halogen atom is preferable.

[0039] In the above formula (A), A １ and A ２ The aromatic ring having 6 to 20 carbon atoms in one embodiment of the formula (A) is G１ and G ２ In addition, in the above formula (A), A １ and A ２ The divalent alicyclic hydrocarbon group having 5 to 20 carbon atoms represented by one embodiment of the formula (A) is G １ and G ２ The same as those explained in A １ and A ２ With respect to the above, examples of the substituent that the aromatic ring having 6 to 20 carbon atoms or the divalent alicyclic hydrocarbon group having 5 to 20 carbon atoms may have include G １ and G ２ Examples of the substituents include the same as those that may be possessed by the group.

[0040] In the above formula (A), SP １ and SP ２ Examples of the divalent aliphatic hydrocarbon group having 1 to 20 carbon atoms represented by one embodiment of the formula (1) include a linear or branched alkylene group having 1 to 20 carbon atoms, a linear or branched alkenylene group having 1 to 20 carbon atoms, and a linear or branched alkynylene group having 1 to 20 carbon atoms. As the linear or branched alkylene group having 1 to 20 carbon atoms, an alkylene group having 1 to 12 carbon atoms is preferred, and an alkylene group having 1 to 10 carbon atoms is more preferred, and suitable examples include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene group. As the linear or branched alkenylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 10 carbon atoms is preferred, and an alkenylene group having 2 to 4 carbon atoms is more preferred, and suitable examples include an ethenylene group. As the linear or branched alkynylene group having 1 to 20 carbon atoms, an alkynylene group having 2 to 10 carbon atoms is preferred, an alkynylene group having 2 to 4 carbon atoms is more preferred, and a suitable example is an ethynylene group. As described above, -CH ２One or more of - may be substituted with -O-, -S-, -NH-, -N(Q)-, or -CO-. Examples of the substituent represented by Q include the substituents described in the above-mentioned substituent group A. Among them, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, or a halogen atom is preferable.

[0041] In the above formula (A), L １ and L ２ Examples of the monovalent organic group represented by include the substituents described in the above-mentioned Substituent Group A, and among these, alkyl groups, aryl groups, heteroaryl groups, alkoxy groups, cyano groups, and carboxy groups are preferred. The alkyl group may be linear, branched, or cyclic, but linear groups are preferred. The alkyl group preferably has 1 to 30 carbon atoms, more preferably 1 to 20, and even more preferably 1 to 10. The aryl group may be monocyclic or polycyclic, but monocyclic groups are preferred. The aryl group preferably has 6 to 25 carbon atoms, more preferably 6 to 10. The heteroaryl group may be monocyclic or polycyclic. The number of heteroatoms constituting the heteroaryl group is preferably 1 to 3. The heteroatoms constituting the heteroaryl group are preferably nitrogen atoms, sulfur atoms, or oxygen atoms. The heteroaryl group preferably has 6 to 18 carbon atoms, more preferably 6 to 12. The alkyl group, aryl group, and heteroaryl group may be unsubstituted or may have a substituent. Examples of the substituent include the substituents described in the above-mentioned substituent group A, and among them, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, or a halogen atom is preferable. １ and L ２ The polymerizable group represented by at least one of the formulae (P-1) to (P-20) is preferably a polymerizable group represented by any one of the formulae (P-1) to (P-20) above.

[0042] In the formula (A), Ar represents any one of aromatic rings selected from the group consisting of groups represented by the following formulae (Ar-1) to (Ar-7), as described above. In the following formulae (Ar-1) to (Ar-7), * represents D in the formula (A). １ or D ２represents the bonding position with

[0043] In the above formula (Ar-1), Q １ represents N or CH, and Q ２ is -S-, -O-, or -N(R ６ )-, R ６ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; Y １ represents an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a substituent, an aromatic heterocyclic group having 3 to 12 carbon atoms which may have a substituent, or an alicyclic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent, and -CH ２ One or more of - may be replaced by -O-, -S- or -NH-. ６ Specific examples of the alkyl group having 1 to 6 carbon atoms represented by one embodiment of the formula (1) 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, an n-pentyl group, and an n-hexyl group. １ Examples of the aromatic hydrocarbon group having 6 to 12 carbon atoms represented by one embodiment of the formula (I) include aryl groups such as a phenyl group, a 2,6-diethylphenyl group, and a naphthyl group. １ Examples of the aromatic heterocyclic group having 3 to 12 carbon atoms represented by one embodiment of the formula (1) include heteroaryl groups such as a thienyl group, a thiazolyl group, a furyl group, a pyridyl group, a benzofuryl group, and a benzothiazolyl group; and groups formed by removing one hydrogen atom from an indole ring, a benzofuran ring, a benzothiophene ring, a benzimidazole ring, a benzothiazole ring, or a benzoxazole ring. １ The aromatic heterocyclic group having 3 to 12 carbon atoms represented by Y is preferably a group obtained by removing one hydrogen atom from a benzofuran ring or a benzothiazole ring. １ Examples of the alicyclic hydrocarbon group having 6 to 20 carbon atoms represented by one embodiment of the formula (1) include a cyclohexylene group, a cyclopentylene group, a norbornylene group, and an adamantylene group. １Examples of the substituent that may be possessed by the group include the substituents described in the above-mentioned substituent group A, and among them, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a nitro group, a cyano group, or a halogen atom is preferable.

[0044] In addition, in the above formulas (Ar-1) to (Ar-7), Z １ , Z ２ and Z ３ each independently represents 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 monovalent aromatic heterocyclic group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, -OR ７ , -NR ８ R ９ , -SR １０ , -COOR １１ , or -COR １２ represents R ７ ~R １２ each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; Z １ and Z ２may be bonded to each other to form an aromatic ring. As the monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alkyl group having 1 to 15 carbon atoms is preferred, an alkyl group having 1 to 8 carbon atoms is more preferred, specifically, a methyl group, an ethyl group, an isopropyl group, a tert-pentyl group (1,1-dimethylpropyl group), a tert-butyl group, or a 1,1-dimethyl-3,3-dimethyl-butyl group is further preferred, 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 monocyclic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, methylcyclohexyl, and ethylcyclohexyl groups; monocyclic unsaturated hydrocarbon groups such as cyclobutenyl, cyclopentenyl, cyclohexenyl, cycloheptenyl, cyclooctenyl, cyclodecenyl, cyclopentadienyl, cyclohexadienyl, cyclooctadienyl, and cyclodecadiene; bicyclo[2.2.1]heptyl, bicyclo[2.2.2]octyl, and tricyclo[5.2.1.0]diene; ２，６ ]decyl group, tricyclo[3.3.1.1 ３，７ ]decyl group, tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodecyl group, adamantyl group, and other polycyclic saturated hydrocarbon groups. Specific examples of 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, with an aryl group having 6 to 12 carbon atoms (particularly a phenyl group) being preferred. Specific examples of the monovalent aromatic heterocyclic group having 6 to 20 carbon atoms include a 4-pyridyl group, a 2-furyl group, a 2-thienyl group, a 2-pyrimidinyl group, and a 2-benzothiazolyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom, a chlorine atom, and a bromine atom being preferred. On the other hand, R ７ ~R １０Specific examples of the alkyl group having 1 to 6 carbon atoms 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, an n-pentyl group, and an n-hexyl group.

[0045] Z １ and Z ２ As described above, may be bonded to each other to form an aromatic ring. For example, Z １ and Z ２ Examples of the structure in which the groups bond to each other to form an aromatic ring include a group represented by the following formula (Ar-1a): In the following formula (Ar-1a), * represents D in the above formula (A). １ or D ２ represents the bonding position with In the above formula (Ar-1a), Q １ , Q ２ and Y １ The examples of the group include those similar to those explained in the above formula (Ar-1).

[0046] In addition, in the above formulas (Ar-2) and (Ar-3), A ３ and A ４ are each independently —O—, —N(R １３ represents a group selected from the group consisting of —, —S—, and —CO—; R １３ represents a hydrogen atom or a substituent. １３ Examples of the substituent represented by one embodiment of the formula (I) include the substituents described in the above-mentioned Substituent Group A, and among them, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, or a halogen atom is preferable.

[0047] In the formula (Ar-2), X represents a nonmetallic atom of Groups 14 to 16. However, the nonmetallic atom may have a hydrogen atom or a substituent bonded thereto. Examples of the nonmetallic atom of Groups 14 to 16 represented by X include an oxygen atom, a sulfur atom, a hydrogen atom, or a nitrogen atom bonded to a substituent [=N-R Ｎ１ , R Ｎ１ represents a hydrogen atom or a substituent.], a carbon atom to which a hydrogen atom or a substituent is bonded [═C—(RＣ１ ) ２ , R Ｃ１ represents a hydrogen atom or a substituent.] Examples of the substituent include the substituents described in the above-mentioned substituent group A, and among them, preferred examples include an alkyl group, an alkoxy group, an alkyl-substituted alkoxy group, a cyclic alkyl group, an aryl group (for example, a phenyl group, a naphthyl group, etc.), a cyano group, an amino group, a nitro group, an alkylcarbonyl group, a sulfo group, and a hydroxyl group.

[0048] In addition, in the above formula (Ar-3), D ７ and D ８ each independently represents a single bond, or —CO—, —O—, —S—, —C(═S)—, or —CR １ R ２ -, -CR ３ =CR ４ -, -NR ５ -, or a divalent linking group formed by a combination of two or more thereof, R １ ~R ５ each independently represents a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 12 carbon atoms. Here, the divalent linking group is D in the above formula (A). １ , D ２ , D ３ , D ４ , D ５ and D ６ Examples of the above-described examples are the same as those described above.

[0049] In addition, in the above formula (Ar-3), SP ３ and SP ４ each independently represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, provided that —CH ２ One or more of - may be substituted with -O-, -S-, -NH-, -N(Q)- or -CO-. Q represents a substituent. Examples of the substituent represented by Q include the substituents described in the above-mentioned substituent group A, and among these, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, or a halogen atom is preferred. Here, the divalent aliphatic hydrocarbon group is a group represented by the formula (A) above, １ and SP２ Examples of the above-described examples are the same as those described above.

[0050] In addition, in the above formula (Ar-3), L ３ and L ４ Each independently represents a monovalent organic group. Here, examples of the monovalent organic group include L １ and L ２ Examples of the above-described examples are the same as those described above.

[0051] In the above formulae (Ar-4) to (Ar-7), Ax represents an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of aromatic hydrocarbon rings and aromatic heterocycles. In the above formulae (Ar-4) to (Ar-7), Ay represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may have a substituent, or an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of aromatic hydrocarbon rings and aromatic heterocycles. Here, the aromatic rings in Ax and Ay may have a substituent, and Ax and Ay may be bonded to form a ring. In addition, 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 those described in paragraphs

[0039] to

[0095] of WO 2014 / 010325. ３ Specific examples of the alkyl group having 1 to 6 carbon atoms represented by 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, an n-pentyl group, and an n-hexyl group. Examples of the substituent include the substituents described in the above-mentioned substituent group A. Among these, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, or a halogen atom is preferred.

[0052] Examples of the liquid crystal compound include compounds represented by the general formula (1) described in JP-A-2010-084032 (particularly, compounds described in paragraphs

[0067] to

[0073] ), compounds represented by the general formula (II) described in JP-A-2016-053709 (particularly, compounds described in paragraphs

[0036] to

[0043] ), and compounds represented by the general formula (1) described in JP-A-2016-081035 (particularly, compounds described in paragraphs

[0043] to

[0055] ), and compounds described in paragraphs

[0025] to

[0056] of WO 2021 / 060427.

[0053] The content of the liquid crystal compound is preferably 50 to 99 mass %, more preferably 60 to 99 mass %, based on the total solid content of the liquid crystal composition, where the total solid content of the liquid crystal composition means the total mass of components excluding the solvent.

[0054] (Other Polymerizable Compounds) The liquid crystal composition may contain other polymerizable compounds in addition to the above-described liquid crystal compounds. The other polymerizable compounds may or may not have liquid crystallinity. Therefore, among the other polymerizable compounds, other polymerizable compounds having liquid crystallinity can be classified as the above-described liquid crystal compounds. Here, the polymerizable group contained in the other polymerizable compound is not particularly limited, and suitable examples thereof include polymerizable groups represented by any of the above-described formulas (P-1) to (P-20).

[0055] The other polymerizable compound is preferably another polymerizable compound having 2 to 4 polymerizable groups, and more preferably another polymerizable compound having 2 polymerizable groups, because this further improves the durability of the liquid crystal layer that is formed.

[0056] Specific examples of other polymerizable compounds include compounds having liquid crystallinity represented by formulas (M1), (M2), and (M3) described in paragraphs

[0030] to

[0033] of JP 2014-077068 A, more specifically, specific examples described in paragraphs

[0046] to

[0055] of the same publication. Furthermore, examples of compounds not having liquid crystallinity include polyfunctional acrylates such as polyethylene glycol diacrylate.

[0057] The content of the other polymerizable compound is preferably 0 to 80 parts by mass, more preferably 0 to 70 parts by mass, relative to 100 parts by mass of the liquid crystal compound. The other polymerizable compound may be used alone or in combination of two or more kinds.

[0058] (Boronic Acid Monomer) The liquid crystal composition preferably contains a boronic acid monomer having a polymerizable group and a boronic acid group represented by the following formula (B) because this improves the adhesion between the support and the liquid crystal layer. Here, the polymerizable group possessed by the boronic acid monomer is not particularly limited, and suitable examples include polymerizable groups represented by any of the above-mentioned formulas (P-1) to (P-20). The number of boronic acid groups represented by the following formula (B) possessed by the boronic acid monomer is not particularly limited, and may be one or multiple (two or more).

[0059] In the above formula (B), * represents a bonding position. １ and R ２ each independently represents a hydrogen atom, an optionally substituted aliphatic hydrocarbon group, an optionally substituted aryl group, or an optionally substituted heterocyclic group; R １ and R ２ may be linked to each other to form a ring.

[0060] R １ and R ２ Examples of the aliphatic hydrocarbon group represented by one embodiment of R include substituted or unsubstituted linear or branched alkyl groups having 1 to 20 carbon atoms (e.g., methyl, ethyl, isopropyl, etc.), substituted or unsubstituted cyclic alkyl groups having 3 to 20 carbon atoms (e.g., cyclohexyl, etc.), and alkenyl groups having 2 to 20 carbon atoms (e.g., vinyl, etc.). １ and R ２ Examples of the aryl group represented by one embodiment of R include a substituted or unsubstituted phenyl group having 6 to 20 carbon atoms (e.g., a phenyl group, a tolyl group, etc.), and a substituted or unsubstituted naphthyl group having 10 to 20 carbon atoms. １ and R ２Examples of the heterocyclic group represented by one embodiment of R include a substituted or unsubstituted 5- or 6-membered ring group containing at least one heteroatom (e.g., a nitrogen atom, an oxygen atom, a sulfur atom, etc.), and examples thereof include a pyridyl group, an imidazolyl group, a furyl group, a piperidyl group, and a morpholino group. 1 and R 2 may be linked together to form a ring, for example, R 1 and R 2 may be linked to form a 4,4,5,5-tetramethyl-1,3,2-dioxaborolane ring. Examples of the substituents that these aliphatic hydrocarbon groups, aryl groups, and heterocyclic groups may have include the substituents described in the above-mentioned substituent group A.

[0061] In the above formula (B), R １ and R ２ is a hydrogen atom, a linear or branched alkyl group having 1 to 3 carbon atoms, or R １ and R ２ are preferably linked to form a ring, and more preferably are hydrogen atoms.

[0062] The molecular weight of the boronic acid monomer is not particularly limited, but is preferably 120 to 1,200, more preferably 180 to 800, in terms of excellent compatibility with polyfunctional monomers.

[0063] A preferred embodiment of the boronic acid monomer is a boronic acid monomer represented by the following formula (B-1), which has better adhesion between the polarizer and the resin layer.

[0064]

[0065] R in formula (B-1) 1 and R 2 is as defined above. Z represents a polymerizable group. The polymerizable group is as defined above. X 1represents a single bond or a divalent linking group. Examples of the divalent linking group include -O-, -CO-, -NH-, -CO-NH-, -COO-, -O-COO-, alkylene groups, arylene groups, heterocyclic groups (heteroaryl groups), and divalent linking groups selected from combinations thereof. Examples of combinations include -arylene group-COO-arylene group-O-alkylene group-, -arylene group-COO-alkylene group-, etc.

[0066] Specific examples of the boronic acid monomer are shown below, but the present invention is not limited thereto.

[0067]

[0068]

[0069]

[0070]

[0071] When the liquid crystal composition contains a boronic acid monomer, the content of the boronic acid monomer is preferably 1 to 10 mass %, more preferably 1 to 9 mass %, and even more preferably 2 to 8 mass %, based on the total solid content of the liquid crystal composition.

[0072] (Solvent) The liquid crystal composition preferably contains a solvent from the viewpoint of workability in forming a retardation film, etc. The solvent is preferably an organic solvent, and specific examples thereof include ketones (e.g., acetone, 2-butanone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, etc.), ethers (e.g., dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (e.g., hexane, etc.), alicyclic hydrocarbons (e.g., cyclohexane, etc.), aromatic hydrocarbons (e.g., toluene, xylene, trimethylbenzene, etc.), halogenated carbons (e.g., dichloromethane, dichloroethane, dichlorobenzene, chlorotoluene, etc.), esters (e.g., acetic acid, Examples of suitable solvents include methyl, ethyl acetate, and butyl acetate), water, alcohols (e.g., methanol, ethanol, isopropanol, butanol, and cyclohexanol), cellosolves (e.g., methyl cellosolve, ethyl cellosolve, and propylene glycol monomethyl ether), cellosolve acetates (e.g., propylene glycol monomethyl ether acetate), sulfoxides (e.g., dimethyl sulfoxide), and amides (e.g., dimethylformamide and dimethylacetamide). These may be used alone or in combination of two or more.

[0073] The content of the solvent is preferably 55 to 85% by mass, more preferably 60 to 80% by mass, based on the total mass of the liquid crystal composition, from the viewpoint of improving the coatability of the liquid crystal composition. When two or more solvents are contained, the total amount is preferably within the above range.

[0074] (Other Components) The liquid crystal composition may contain other components in addition to those described above, such as a polymerization initiator, a leveling agent, a surfactant, a tilt control agent, an alignment aid, a plasticizer, and a crosslinking agent.

[0075] <Formation Method> Examples of methods for forming a liquid crystal layer (positive C plate) include a method in which rod-shaped liquid crystal compounds are vertically aligned using the liquid crystal composition described above, followed by polymerization to fix the alignment. While the conditions for achieving vertical alignment are not particularly limited, a heat treatment is preferably performed, and a cooling treatment after the heat treatment is more preferred. From the standpoint of manufacturability, the heating temperature in the heat treatment is preferably 10 to 250°C, more preferably 50 to 200°C, and even more preferably 65 to 150°C. The heating time in the heat treatment is preferably 1 to 300 seconds, more preferably 1 to 120 seconds. The temperature in the cooling treatment after the heat treatment is not particularly limited as long as it is lower than the heating temperature in the heat treatment, but is preferably room temperature (23°C) to 80°C. While the polymerization conditions are not particularly limited, ultraviolet light is preferably used for polymerization by light irradiation. The irradiation dose is 10 mJ / cm. ２ ~50 J / cm ２ is preferred, and 20 mJ / cm ２ ~5 J / cm ２ More preferably, 30 mJ / cm ２ ~3 J / cm ２ is more preferably 50 to 1000 mJ / cm ２ is particularly preferred. In order to promote the polymerization reaction, the polymerization may be carried out under heating conditions. The vertical alignment, also called homeotropic alignment, refers to an alignment in which the angle between the surface (main surface) of the liquid crystal layer and the director of the rod-shaped liquid crystal compound is in the range of 70° to 90°, preferably in the range of 80° to 90°, and more preferably in the range of 85° to 90°.

[0076] In the present invention, for the reason that alignment irregularities (alignment defects) in the liquid crystal layer are suppressed, the difference between the solubility parameter (hereinafter also abbreviated as "SP value") of the polymer contained in the above-mentioned polymer film (support) and the solubility parameter of the liquid crystal compound contained in the largest amount among the liquid crystal compounds contained in the above-mentioned liquid crystal composition (hereinafter also abbreviated as "ΔSP value") is preferably 8.8 or more, more preferably 9.5 or more. The upper limit of the ΔSP value is not particularly limited, but is preferably 15.0 or less, more preferably 12.5 or less.

[0077] Here, the ΔSP value refers to the δa value of the SP value calculated by the method of Hoy et al. (see VAN KREVELEN, D.W., "PROPERTIES OF POLYMERS (ED. 3)", Elsevier Publishing (1990)). The δa value can be calculated by the following formula (X) using the SP values ​​(δd, δp, δh) calculated by the method of Hoy et al.: δa=(δd ２ +δp ２ +δh ２ ) ０．５ Formula (X) According to the method of Hoy et al., the values ​​of δd, δp, and δh can be calculated from the chemical structural formula (the structure of the repeating unit in the case of a polymer) of the compound to be determined (i.e., polymer or liquid crystal compound). However, if the chemical structural formula is unknown, the SP value (SP ｄ , SP ｐ , SP ｈ The solubility of the compound in a solvent with known solubility is examined, and the SP value can be calculated from the central coordinates of a sphere that contains only the point of the dissolved solvent. In addition, when the polymer is a copolymer having two or more types of repeating units, the SP values ​​(δd, δp, δh) are calculated using a structural formula in which the bonding site of each repeating unit is replaced with a hydrogen atom, and the ΔSP value between each repeating unit and the above-mentioned liquid crystal compound is calculated, and the average value based on the molar ratio of each repeating unit is used.

[0078] Regarding the SP value of the polymer, when the polymer film contains two or more polymers, the ΔSP values ​​(δd, δp, δh) of each polymer are calculated, and the average value is adopted based on the molar ratio of each polymer. Furthermore, when two or more liquid crystal compounds are present in the liquid crystal composition at the largest content (for example, when two liquid crystal compounds with different structures are present at 40 mass %), the requirement that the ΔSP value be 8.8 or more may be satisfied in relation to at least one of the liquid crystal compounds at the largest content.

[0079] In the present invention, the polymer contained in the polymer film (support) preferably satisfies the following formula (1) because cracks (breaks) in the retardation film are suppressed during high-temperature durability (hereinafter also referred to as "excellent crack resistance"). Furthermore, in the following formula (1), the product of Nw and ΔSP(A) (Nw × ΔSP(A)) is more preferably 900 or more. The upper limit of this product is not particularly limited, but is preferably 10,000 or less, more preferably 5,000 or less. Nw × ΔSP(A) ≧ 700 (1) In the above formula (1), Nw represents the weight-average degree of polymerization of the polymer contained in the polymer film. Furthermore, ΔSP(A) represents the difference between the solubility parameter of the polymer contained in the polymer film and the solubility parameter of acetone.

[0080] Here, the weight-average degree of polymerization (Nw) in the above formula (1) is the value calculated from "Mw / Mp", which is the weight-average molecular weight (Mw) of the polymer contained in the polymer film divided by the average molecular weight (Mp) per repeating unit (unit) of the polymer contained in the polymer film. The weight-average molecular weight (Mw) is the weight-average molecular weight measured by dissolving the polymer contained in the polymer film in tetrahydrofuran and using GPC (gel permeation chromatography). When the polymer contained in the polymer film contains two or more types of repeating units, the average molecular weight (Mp) is calculated by averaging the molecular weights of the repeating units based on the molar ratio of each repeating unit. When the polymer film contains two or more types of polymers, the weight-average degree of polymerization calculated from each polymer is calculated by averaging the molar ratio of each polymer.

[0081] Furthermore, ΔSP(A) in the above formula (1), i.e., the difference between the solubility parameter of the polymer contained in the polymer film and the solubility parameter of acetone, can be calculated by the method described above for the ΔSP value.

[0082] [Polarizing Plate] The polarizing plate of the present invention is a polarizing plate having the above-mentioned retardation film of the present invention and a polarizer. In the polarizing plate of the present invention, the polarizer, the liquid crystal layer of the retardation film, and the support of the retardation film are preferably arranged in this order.

[0083] [Polarizer] The polarizer of the polarizing plate of the present invention is not particularly limited as long as it has the function of converting light into specific linearly polarized light, and conventionally known absorptive polarizers and reflective polarizers can be used. Examples of absorptive polarizers include iodine-based polarizers, dye-based polarizers using dichroic dyes, and polyene-based polarizers. Iodine-based polarizers and dye-based polarizers include coated polarizers and stretched polarizers, and either type can be used. However, polarizers produced by adsorbing iodine or a dichroic dye onto polyvinyl alcohol and stretching the resulting film are preferred. Furthermore, methods for obtaining polarizers by stretching and dyeing a laminated film having a polyvinyl alcohol layer formed on a substrate are described in Japanese Patent Nos. 5,048,120, 5,143,918, 4,691,205, 4,751,481, and 4,751,486. These known techniques related to polarizers can also be preferably used. As the reflective polarizer, a polarizer in which thin films with different birefringence are laminated, a wire grid polarizer, a polarizer in which a cholesteric liquid crystal having a selective reflection region is combined with a quarter-wave plate, etc. are used. Among them, a polyvinyl alcohol-based resin (-CH ２ A polymer containing —CHOH— as a repeating unit, particularly at least one selected from the group consisting of polyvinyl alcohol and an ethylene-vinyl alcohol copolymer, is preferred.

[0084] In the present invention, the thickness of the polarizer is not particularly limited, but is preferably 5 to 40 μm, more preferably 5 to 30 μm, and even more preferably 5 to 20 μm. The above thickness allows for the reduction in thickness of display devices.

[0085] In the polarizing plate of the present invention, the retardation film is preferably arranged so that the slow axis of the support thereof is perpendicular to or parallel to the absorption axis of the polarizer, and more preferably so that the slow axis is parallel to the absorption axis of the polarizer.

[0086] [Polarizer Protective Film] The polarizing plate of the present invention may have a polarizer protective film disposed on the surface of the polarizer. The polarizer protective film may be disposed on only one side of the polarizer (the surface opposite the retardation film side) or on both sides of the polarizer. The configuration of the polarizer protective film is not particularly limited, and may be, for example, a so-called transparent support or hard coat layer, or a laminate of a transparent support and a hard coat layer. The hard coat layer may be a known layer, for example, a layer obtained by polymerizing and curing a polyfunctional monomer. The transparent support may also be a known transparent support. For example, materials for forming the transparent support may include cellulose-based polymers (hereinafter referred to as cellulose acylate), such as triacetyl cellulose, thermoplastic norbornene-based resins (such as Zeonex and Zeonor manufactured by Zeon Corporation and Arton manufactured by JSR Corporation), acrylic resins, and polyester resins. The thickness of the polarizer protective film is not particularly limited, but is preferably 50 μm or less, for reasons such as enabling the thickness of the polarizing plate to be thin.

[0087] [Adhesive Layer] The polarizing plate of the present invention may have an adhesive layer disposed between the retardation film (particularly the liquid crystal layer) and the polarizer. The adhesive layer used for laminating the retardation film and the polarizer refers to, for example, a substance having a ratio of storage modulus G' to loss modulus G" (tan δ = G" / G') measured with a dynamic viscoelasticity measuring device of 0.001 to 1.5, and includes so-called adhesives and substances that tend to creep. Adhesives that can be used in the present invention include, but are not limited to, polyvinyl alcohol-based adhesives.

[0088] [Image Display Device] The image display device of the present invention is an image display device having the polarizing plate of the present invention described above. 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") display panel, and a plasma display panel. Among these, a liquid crystal cell and an organic EL display panel are preferred, and a liquid crystal cell is more preferred. That is, as the image display device, a liquid crystal display device using a liquid crystal cell as the display element or an organic EL display device using an organic EL display panel as the display element is preferred, and a liquid crystal display device is more preferred.

[0089] [Liquid Crystal Display Device] A liquid crystal display device, which is an example of an image display device, is a liquid crystal display device having the polarizing plate of the present invention described above and a lateral electric field mode liquid crystal cell, and is preferably a liquid crystal display device in which, from the viewing side, a polarizer of the polarizing plate, a liquid crystal layer of the polarizing plate, a support of the polarizing plate, and the liquid crystal cell are arranged in this order. The liquid crystal cell constituting the liquid crystal display device will be described in detail below.

[0090] <Liquid Crystal Cell> The liquid crystal cell used in the liquid crystal display device of the present invention is preferably an in-plane switching (IPS) liquid crystal cell. The liquid crystal cell used in the liquid crystal display device is preferably, but not limited to, a vertical alignment (VA) mode, optically compensated bend (OCB) mode, in-plane switching (IPS) mode, fringe-field switching (FFS) mode, or twisted nematic (TN) mode. In a TN mode liquid crystal cell, rod-shaped liquid crystal molecules are aligned substantially horizontally when no voltage is applied, and are further twisted at an angle of 60 to 120°. TN mode liquid crystal cells are most commonly used in color thin film transistor (TFT) liquid crystal displays, and are described in numerous literature. In a VA mode liquid crystal cell, rod-shaped liquid crystal molecules are aligned substantially vertically when no voltage is applied. VA mode liquid crystal cells include (1) narrowly defined VA mode liquid crystal cells in which rod-shaped liquid crystal molecules are aligned substantially vertically when no voltage is applied and substantially horizontally when a voltage is applied (described in Japanese Patent Application Laid-Open No. 2-176625), (2) multi-domain VA mode liquid crystal cells (described in SID97, Digest of tech. Papers (Proceedings) 28 (1997) 845) in order to widen the viewing angle (MVA mode liquid crystal cells), (3) n-ASM mode liquid crystal cells in which rod-shaped liquid crystal molecules are aligned substantially vertically when no voltage is applied and substantially horizontally when a voltage is applied (described in Proceedings of the Japan Liquid Crystal Symposium 58-59 (1998)), and (4) SURVIVAL mode liquid crystal cells (announced at LCD International 98). The VA mode liquid crystal cell may be any of a PVA (Patterned Vertical Alignment) type, an optical alignment type, and a PSA (Polymer-Sustained Alignment) type. Details of these modes are described in Japanese Patent Laid-Open No. 2006-215326 and Japanese Patent Laid-Open No. 2008-538819.In an IPS mode liquid crystal cell, rod-shaped liquid crystal molecules are aligned substantially parallel to the substrates, and when an electric field parallel to the substrate surface is applied, the liquid crystal molecules respond in a planar manner. In the IPS mode, a black display is achieved when no electric field is applied, and the absorption axes of a pair of upper and lower polarizing plates are perpendicular to each other. Methods for reducing light leakage during black display in oblique directions and improving the viewing angle using an optical compensation sheet are disclosed in JP-A-10-54982, JP-A-11-202323, JP-A-9-292522, JP-A-11-133408, JP-A-11-305217, JP-A-10-307291, and the like.

[0091] [Organic EL Display Device] An organic EL display device, which is one example of an image display device, may have, in this order from the viewing side, the polarizing plate of the present invention (a polarizing plate with a polarizer disposed on the viewing side). The organic EL display panel is a display panel configured using organic EL elements each having an organic light-emitting layer (organic electroluminescence layer) sandwiched between electrodes (a cathode and an anode). The configuration of the organic EL display panel is not particularly limited, and a known configuration may be used.

[0092] The present invention will be described in more detail below with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the examples shown below.

[0093] [Example 1] [Preparation of Resin Composition 1] According to the example of Japanese Patent No. 5119250, a resin composition 1 was prepared using 77.82 parts of 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane (hereinafter abbreviated as "SPG"), 54.43 parts of 9,9-bis(4-hydroxy-3-methylphenyl)fluorene (hereinafter abbreviated as "BCF"), 89.29 parts of diphenyl carbonate, and 1.8 × 10 tetramethylammonium hydroxide as a catalyst. －２ parts and sodium hydroxide 1.6 x 10 －４ Parts were used to prepare Resin Composition 1. The molar ratio of SPG part to BCF part was 64:36.

[0094] [Preparation of Support] According to the examples of Japanese Patent No. 5119250, the above-mentioned resin composition 1 was formed into a film, and then uniaxially stretched in the longitudinal direction to obtain a support 1 (polymer film 1) having a width of 300 mm and a length of 300 m. A sample of 50 mm x 10 mm was cut out from the center of the obtained film, and the sample was used to measure the photoelastic constant using a Spectroellipsometer M-220 manufactured by JASCO Corporation, and the phase difference (retardation) using an AxoScan OPMF-1 (manufactured by Optoscience Co., Ltd.). The results are shown in Table 2 below. In Table 2 below, "Positive A" in the classification of the optical properties of the support refers to a positive A plate.

[0095] [Preparation of Liquid Crystal Composition I] Liquid crystal composition I having the following composition was prepared. Liquid crystal composition I -------------------------------- 10.00 parts by mass of liquid crystal compound R1 shown below 24.80 parts by mass of liquid crystal compound R2 shown below 24.80 parts by mass of liquid crystal compound R3 shown below 20.20 parts by mass of liquid crystal compound R4 shown below 20.20 parts by mass of liquid crystal compound R5 shown below 10.00 parts by mass of liquid crystal compound A1 shown below 3.00 parts by mass of alignment aid B1 shown below 8.00 parts by mass of compound C1 shown below 3.00 parts by mass of photopolymerization initiator S1 shown below 0.21 parts by mass of surfactant P1 shown below 232.80 parts by mass of cyclopentanone 60.50 parts by mass of methyl ethyl ketone 9.10 parts by mass

[0096] Liquid crystal compound R1

[0097] Liquid crystal compound R2

[0098] Liquid crystal compound R3 (in the following formula, t-Bu represents a tert-butyl group)

[0099] Liquid crystal compound R4

[0100] Liquid crystal compound R5

[0101] Liquid crystal compound A1

[0102] Compound B1 (alignment aid)

[0103] Compound C1

[0104] Photopolymerization initiator S1

[0105] Surfactant P1 (weight average molecular weight: 11,200, the values ​​in the following formula indicate the content (mol %) of each repeating unit relative to the total repeating units.)

[0106] [Preparation of Retardation Film L1] The surface of the support 1 was subjected to a discharge of 150 W min / m ２ The corona-treated surface was then coated with the liquid crystal composition I prepared as described above using a die coater to form a composition layer. The composition was then heated at 85°C for 60 seconds to dry the solvent and ripen the liquid crystal compound into an aligned state. The composition was then irradiated with ultraviolet light (150 mJ / cm) at 60°C under a nitrogen purge with an oxygen concentration of 100 ppm. ２ ) to fix the vertical alignment state, and a liquid crystal layer I with a thickness of 2.0 μm was formed. In this way, 300 m of the liquid crystal layer I was continuously applied to the support 1, and a long retardation film L1 was produced. The retardation of the produced retardation film L1 was measured, and the retardation of the liquid crystal layer I was calculated by subtracting the retardation of the support 1 measured in advance. The retardation in the thickness direction RthC(550) was -90 nm, and RthC(450) / RthC(550) was 0.88, confirming that the liquid crystal layer I was a positive C plate (nz>nx=ny).

[0107] Example 2 Preparation of Retardation Film L2 A retardation film L2 was prepared in the same manner as in Example 1, except that the liquid crystal composition I was replaced with a liquid crystal composition II having the following composition. Liquid crystal composition II ------------------------------------------------ 10.00 parts by mass of the following liquid crystal compound R6 54.00 parts by mass of the above liquid crystal compound R1 28.00 parts by mass of the following liquid crystal compound R7 8.00 parts by mass of the following liquid crystal compound T1 4.50 parts by mass of the above compound B1 (alignment aid) 12.00 parts by mass of NK Ester A-600 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 1.50 parts by mass of the above polymerization initiator S1 0.17 parts by mass of the above surfactant P1 225.00 parts by mass of methyl ethyl ketone 25.00 parts by mass of methanol ------------------------------------------------

[0108] Liquid crystal compound R6

[0109] Liquid crystal compound R7 (a mixture of the following liquid crystal compounds (RA), (RB), and (RC) in a mass ratio of 83:15:2. Me in the following liquid crystal compounds (RB) and (RC) represents a methyl group.)

[0110] Liquid crystal compound T1

[0111] The retardation of the prepared retardation film L2 was measured, and the retardation of the liquid crystal layer II was calculated by subtracting the retardation of the support 1 measured in advance. As a result, the retardation in the thickness direction RthC(550) was −101 nm, and RthC(450) / RthC(550) was 0.95, confirming that the liquid crystal layer II was a positive C plate (nz>nx=ny).

[0112] Example 3 Preparation of Retardation Film L3 A retardation film L3 was prepared in the same manner as in Example 2, except that the molar ratio of SPG:BCF in the resin composition 1 was changed to 50:50.

[0113] [Example 4] [Preparation of Resin Composition 2] 1.90 mol of BCF, 1.90 mol of dimethyl 1,4-cyclohexanedicarboxylate (CHD), and 2×10 －４ Molar and calcium acetate monohydrate 8 x 10 －４ The mixture was heated to 230°C and melted under stirring. －４ Mole, germanium oxide 20 x 10 －４ The by-product methanol was removed by gradually increasing the temperature and reducing the pressure until the temperature reached 270°C and the pressure reached 0.13 kPa or less. Next, stirring was stopped and the contents were removed from the reactor to prepare a resin composition. The molar ratio of BCF part to CHD part was 50:50.

[0114] [Preparation of Retardation Film L4] A retardation film L4 was prepared in the same manner as in Example 1, except that the resin composition 2 described above was used instead of the resin composition 1.

[0115] Example 5 Preparation of Retardation Film L5 A retardation film L5 was prepared in the same manner as in Example 4, except that the liquid crystal composition II was used instead of the liquid crystal composition I.

[0116] [Example 6] [Preparation of Retardation Film L6] A retardation film L6 was prepared in the same manner as in Example 5, except that BCF in the resin composition 2 was changed to 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (hereinafter abbreviated as "BPEF").

[0117] [Example 7] [Preparation of Retardation Film 7] A retardation film L7 was prepared in the same manner as in Example 5, except that BCF in the resin composition 2 was changed to 9,9-bis(4-hydroxyphenyl)fluorene (hereinafter abbreviated as "BPF").

[0118] [Example 8] [Preparation of Retardation Film 8] A retardation film L8 was prepared in the same manner as in Example 5, except that BCF in the resin composition 2 was changed to bis(9-hydroxymethylfluoren-9-yl)methane (hereinafter abbreviated as "BHIM").

[0119] [Example 9] [Preparation of Retardation Film 9] A retardation film L9 was prepared in the same manner as in Example 5, except that BCF in the resin composition 2 was changed to bis[9-(3-hydroxypropyl)-fluoren-9-yl]methane (hereinafter abbreviated as "BHPIM").

[0120] Example 10 Preparation of Retardation Film 10 A retardation film L10 was prepared in the same manner as in Example 2, except that BCF in the resin composition 1 was changed to BHIM.

[0121] [Example 11] [Preparation of Retardation Film 11] A retardation film L11 was prepared in the same manner as in Example 2, except that BCF in the resin composition 1 was changed to 6,6'-dihydroxy-3,3,3',3'-tetramethyl-1,1'-spirobiindane (hereinafter abbreviated as "SBI").

[0122] Example 12 Preparation of Retardation Film L12 A retardation film L12 was prepared in the same manner as in Example 1, except that the liquid crystal composition I was replaced with a liquid crystal composition III having the following composition. ------------------------------------------------ Liquid Crystal Composition III -------------------------------------------------- 100.0 parts by mass of the above liquid crystal compound R7 4.5 parts by mass of the above compound B1 (alignment aid) 2.0 parts by mass of the following alignment aid A1 8.0 parts by mass A-TMMT (manufactured by Shin-Nakamura Chemical Co., Ltd.) 5.0 parts by mass of the following photopolymerization initiator S2 2.0 parts by mass of the following photopolymerization initiator S3 0.4 parts by mass of the following surfactant P2 0.5 parts by mass of the above surfactant P1 Acetone 353.0 parts by mass Propylene glycol monomethyl ether acetate 122.0 parts by mass Methanol 15.0 parts by mass

[0123] Orientation Aid A1

[0124] Photopolymerization initiator S2

[0125] Photopolymerization initiator S3

[0126] Surfactant P2 (weight average molecular weight: 15,000; in the following formula, the numbers in parentheses for the repeating units represent mass %.)

[0127] [Example 13] [Preparation of Retardation Film L13] A retardation film L13 was prepared in the same manner as in Example 2, except that it was biaxially stretched in the length direction and the width direction. In Table 2 below, "Negative B" in the classification of the optical properties of the support refers to a negative B plate (nx>nz>ny).

[0128] Example 14 Preparation of Retardation Film L14 A retardation film L14 was prepared in the same manner as in Example 4, except that the liquid crystal composition III was used instead of the liquid crystal composition I.

[0129] Example 15 Preparation of Retardation Film L15 A retardation film L15 was prepared in the same manner as in Example 1, except that the following liquid crystal composition IV was used instead of the liquid crystal composition I. Liquid Crystal Composition IV 10.00 parts by mass of the above liquid crystal compound R6 54.00 parts by mass of the above liquid crystal compound R1 28.00 parts by mass of the above liquid crystal compound R7 8.00 parts by mass of the above liquid crystal compound T1 12.00 parts by mass of NK Ester A-600 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 1.50 parts by mass of the above polymerization initiator S1 0.17 parts by mass of the above surfactant P1 225.00 parts by mass of methyl ethyl ketone 25.00 parts by mass of methanol ----------------------------------------------------------------

[0130] Example 16 Preparation of Retardation Film L16 A retardation film L16 was prepared in the same manner as in Example 2, except that the molar ratio of SPG:BCF in Resin Composition 1 was changed to 20:80.

[0131] [Example 17] [Preparation of Retardation Film L17] A retardation film L17 was prepared in the same manner as in Example 2, except that isosorbide (hereinafter abbreviated as "ISB") was used instead of SPG in the resin composition 1, and the molar ratio of the ISB part to the BCF part was ISB:BCF = 50:50.

[0132] Example 18 Preparation of Retardation Film L18 A retardation film L18 was prepared in the same manner as in Example 17, except that the liquid crystal composition III was used instead of the liquid crystal composition II.

[0133] Example 19 Preparation of Retardation Film L19 A retardation film L19 was prepared in the same manner as in Example 2, except that the following liquid crystal composition IV was used instead of the liquid crystal composition II.

[0134] Liquid Crystal Composition IV - 100.00 parts by mass of the following liquid crystal compound R8 - 4.50 parts by mass of the above compound B1 (alignment aid) - 12.00 parts by mass of NK Ester A-600 (manufactured by Shin-Nakamura Chemical Co., Ltd.) - 1.50 parts by mass of the above polymerization initiator S1 - 0.17 parts by mass of the above surfactant P2-1 - 225.00 parts by mass of methyl ethyl ketone - 25.00 parts by mass of methanol -

[0135] Liquid crystal compound R8

[0136] Example 20 Preparation of Retardation Film L20 A retardation film L20 was prepared in the same manner as in Example 5, except that the liquid crystal composition IV was used instead of the liquid crystal composition II.

[0137] [Example 21] [Preparation of resin composition 21] Resin composition 21 was prepared according to the examples of Japanese Patent No. 3995387 so that the molar ratio of SPG part: BCF part was 64: 36. [Preparation of retardation film L21] Retardation film L21 was prepared in the same manner as in Example 2, except that resin composition 21 was used instead of resin composition 1.

[0138] Example 22 Preparation of Retardation Film L22 A retardation film L22 was prepared in the same manner as in Example 4, except that the weight average degree of polymerization of resin composition 2 was adjusted to 180.

[0139] Example 23 Preparation of Retardation Film L23 A retardation film L23 was prepared in the same manner as in Example 16, except that the thickness of the support was adjusted to 45 μm.

[0140] Example 24 A retardation film L24 was produced in the same manner as in Example 2, except that the thickness of the support was adjusted to 120 μm.

[0141] Example 25 A retardation film L25 was produced in the same manner as in Example 22, except that the thickness of the support was adjusted to 30 μm.

[0142] [Example 26] [Preparation of Retardation Film L26] The resin film used in Example 1 of JP-A No. 2023-180135 was uniaxially stretched in the length direction to prepare a support having a width of 300 mm and a length of 300 m. Retardation film L26 was prepared in the same manner as in Example 1, except that the support prepared above was used instead of support 1 (polymer film 1). The materials constituting the resin film are abbreviated as follows: Ethyl cellulose ("ETHOCEL standard 100" manufactured by The Dow Chemical Company): ETHOCEL 9-vinylcarbazole: BCA α-cyano-4-isobutyl hydroxycinnamate: CHI Isobutyl acrylate: AI

[0143] Example 27 Preparation of Retardation Film L27 A retardation film L27 was prepared in the same manner as in Example 26, except that liquid crystal composition II was used instead of liquid crystal composition I.

[0144] Comparative Example 1 Preparation of Retardation Film H1 A retardation film H1 was prepared in the same manner as in Example 1, except that bisphenol A (hereinafter abbreviated as "BPA") was used instead of SPG in Resin Composition 1, and the resin composition was prepared so that the molar ratio of the BPA part to the BCF part was BPA:BCF = 33:67.

[0145] Comparative Example 2 Preparation of Retardation Film H2 A retardation film H2 was prepared in the same manner as in Comparative Example 1, except that the liquid crystal composition II was used instead of the liquid crystal composition I.

[0146] Comparative Example 3 Preparation of Retardation Film H3 A retardation film H3 was prepared in the same manner as in Comparative Example 1, except that the liquid crystal composition III was used instead of the liquid crystal composition I.

[0147] [Comparative Example 4] [Preparation of Retardation Film H4] As the substrate, the polycarbonate film used in Example 1 of Patent Document 1 (WO 2020 / 045224) [trade name: Pure Ace (manufactured by Teijin Limited), Re1 (550) = 154 nm, Rth1 (550) = 77 nm, film thickness 76 μm] was used. A retardation film H4 was prepared in the same manner as in Example 2.

[0148] [Preparation of Liquid Crystal Display Device for Evaluating Display Performance] [Preparation of Protective Film 1] <Preparation of Core Layer Cellulose Acylate Dope 1> The following composition was charged into a mixing tank and stirred to dissolve each component, thereby preparing Core Layer Cellulose Acylate Dope 1. ------------------------------------------------ Core Layer Cellulose Acylate Dope 1 ---------------------------------------------------------------- Cellulose acetate having an acetyl substitution degree of 2.88: 100 parts by mass Ester oligomer (Compound 1-1 below): 10 parts by mass Durability improver (Compound 1-2 below): 4 parts by mass Ultraviolet absorber (Compound 1-3 below): 3 parts by mass Methylene chloride (First solvent): 438 parts by mass Methanol (Second solvent): 65 parts by mass

[0149] Compound 1-1

[0150] Compound 1-2

[0151] Compound 1-3

[0152] <Preparation of Outer Layer Cellulose Acylate Dope 1> 10 parts by mass of the following matting agent dispersion 1 was added to 90 parts by mass of the above core layer cellulose acylate dope 1 to prepare outer layer cellulose acylate dope 1. ---------------------------------------------------------------- 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 Core layer cellulose acylate dope 1 1 part by mass

[0153] <Preparation of Protective Film 1> The above-mentioned core layer cellulose acylate dope 1 and outer layer cellulose acylate dope 1 on both sides were simultaneously cast onto a drum at 20°C from a casting nozzle. When the solvent content of the film on the drum was approximately 20% by mass, the film was peeled off from the drum, and both ends of the obtained film in the width direction were fixed with tenter clips. The film was then dried while being stretched 1.2 times in the transverse direction while the residual solvent in the film was 3 to 15% by mass. The obtained film was then transported between the rolls of a heat treatment device to prepare a 25 μm-thick cellulose acylate film 1, which was used as protective film 1.

[0154] [Preparation of Protective Film 1 with Hard Coat Layer] A curable composition for hard coat (Hard Coat 1) shown in the table below was prepared as a coating liquid for forming a hard coat layer.

[0155]

[0156] In Table 1 above, the structure of UV (ultraviolet) initiator 1 is shown below.

[0157] The curable composition for hard coating was applied to the surface of the protective film 1 prepared above, then dried at 100°C for 60 seconds, and cured by irradiating with UV at 1.5 kW and 300 mJ under conditions of nitrogen of 0.1% or less to prepare a protective film 1 with a hard coating layer having a thickness of 5 µm. The thickness of the hard coating layer was adjusted by adjusting the coating amount using a slot die in a die coating method.

[0158] [Preparation of Polarizing Plate 1 with One-Side Protective Film] (1) Saponification of Film The prepared hard-coat-layer-attached protective film 1 was immersed in a 4.5 mol / L aqueous sodium hydroxide solution (saponification solution) adjusted to 37°C for 1 minute, then washed with water. It was then immersed in a 0.05 mol / L aqueous sulfuric acid solution for 30 seconds and then passed through a water washing bath. The resulting film was then repeatedly drained with an air knife three times. After removing the water, it was retained in a drying zone at 70°C for 15 seconds and dried to prepare a saponified hard-coat-layer-attached protective film 1. (2) Preparation of Polarizer Following the example of JP 2016-148724 A, a difference in peripheral speed was applied between two pairs of nip rolls, and the film was stretched in the longitudinal direction to prepare a polarizer with a film thickness of 15 μm. The polarizer thus prepared was designated polarizer 1. (3) Bonding The polarizer 1 thus obtained and the saponified hard-coat-layer-attached protective film 1 were bonded together by roll-to-roll bonding using a 3% aqueous solution of PVA (PVA-117H, manufactured by Kuraray Co., Ltd.) as an adhesive so that the polarization axis and the longitudinal direction of the film were perpendicular to each other, thereby producing a polarizing plate 1 with a single-side protective film (hereinafter also simply referred to as "polarizing plate 1"). In this bonding, the cellulose acylate film side of the protective film was attached to the polarizer side.

[0159] [Preparation of First Polarizing Plate] The liquid crystal layer of each retardation film prepared in the Examples and Comparative Examples and the polarizer surface of the polarizing plate 1 were attached together by a roll-to-roll method using a 3% aqueous solution of PVA (PVA-117H, manufactured by Kuraray Co., Ltd.) as an adhesive so that the polarization axis and the longitudinal direction of the film were perpendicular to each other, thereby preparing a first polarizing plate.

[0160] [Preparation of Protective Film 2] <Preparation of PMMA (Polymethyl Methacrylate) Dope> The following dope composition was charged into a mixing tank and stirred to dissolve each component, thereby preparing a PMMA dope. ------------------------------------------------ PMMA dope ------------------------------------------------ PMMA resin 100 parts by mass Sumilizer GS (manufactured by Sumitomo Chemical Co., Ltd.) 0.1 parts by mass Dichloromethane 426 parts by mass Methanol 64 parts by mass

[0161] <Preparation of Protective Film 2> The PMMA dope described above was uniformly cast onto a stainless steel band (casting support) from a casting die (band casting machine). The film was peeled off when the solvent content in the cast film was approximately 20% by mass, and both ends of the film in the width direction were fixed with tenter clips. The film was then stretched in the transverse direction at a stretch ratio of 1.1 times while being dried. The resulting film was then transported between the rolls of a heat treatment device and further dried. A 20 μm-thick PMMA film was prepared, designated Protective Film 2.

[0162] [Preparation of Second Polarizing Plate] <Preparation of Adhesive Composition 1> The following compounds were mixed in the ratios shown below to prepare adhesive composition 1. Polymerizable compound (Aronix M-220, manufactured by Toagosei Co., Ltd.): 20 parts by mass Polymerizable compound (4-hydroxybutyl acrylate, manufactured by Nippon Kasei Co., Ltd.): 40 parts by mass Polymerizable compound (2-ethylhexyl acrylate, manufactured by Mitsubishi Chemical Corporation): 40 parts by mass Polymerization initiator (Irgacure 907, manufactured by BASF): 1.5 parts by mass Sensitizer (KAYACURE DETX-S, manufactured by Nippon Kayaku Co., Ltd.): 0.5 parts by mass

[0163] <Preparation of Second Polarizing Plate> The polarizer-attached surface of the protective film 2 was subjected to a discharge of 150 W·min / m ２After corona treatment with a fluorine-based solvent, adhesive composition 1 was applied to a film thickness of 0.5 μm. Thereafter, the adhesive-coated surface was attached to the polarizer surface of polarizing plate 1 with a single-side protective film, and ultraviolet light was applied at 300 mJ / cm from the support side of protective film 2 at 40° C. in an atmospheric atmosphere. ２ Thereafter, the film was dried at 60° C. for 3 minutes to prepare a second polarizing plate.

[0164] [Preparation of Liquid Crystal Display Device] The front and back polarizing plates were peeled off from a commercially available liquid crystal display device (iPad (registered trademark), manufactured by Apple) (a liquid crystal display device including an FFS mode liquid crystal cell), and the first polarizing plate including each retardation film prepared in the examples and comparative examples was placed on the viewing side, and the second polarizing plate was placed on the backlight side, so that the absorption axes of the polarizers in each polarizing plate were perpendicular to each other, and the alignment direction of the liquid crystal in the liquid crystal cell was perpendicular to the absorption axis of the polarizer in the first polarizing plate. A liquid crystal display device was prepared to evaluate the display performance of each retardation film prepared in the examples and comparative examples. The liquid crystal cell in the liquid crystal display device contained a color filter layer on the substrate on the first polarizing plate side, and a TFT layer on the substrate on the second polarizing plate side, and each Rth (550) was 10 nm and 2 nm. The Δn · d of the liquid crystal compound in the liquid crystal cell was 340, and the tilt angle of the liquid crystal compound with respect to the substrate surface was 0.1 °.

[0165] [Evaluation of Mounting Unevenness] The manufactured liquid crystal display device was placed in a dark room in black display mode, and visually observed at a polar angle of 60° and around one azimuth angle, and evaluated according to the following criteria. <Evaluation criteria> A: No visible unevenness in either light leakage or color. B: Light leakage and color unevenness are visible, but only in 50% or less of the total area. C: Light leakage and color unevenness are visible in 50% or more of the total area.

[0166] [Evaluation of Oblique Light Leakage] The prepared liquid crystal display device was set to black display in a dark room, and the black luminance was measured using a measuring device (EZ-Contrast XL88, manufactured by ELDIM). The average value of luminance at azimuth angles of 45°, 135°, 225°, and 315° at a polar angle of 60° was taken as light leakage Y, and was evaluated according to the following criteria. Note that the azimuth angle was defined so that the absorption axis direction of the polarizer on the viewing side (first polarizer) was 0° (and 180°), and the absorption axis direction of the polarizer on the backlight side (second polarizer) was 90° (and 270°). <Evaluation Criteria> A:Y<0.6 (cd / m ２ ) B: 0.6 (cd / m ２ )≦Y<0.8(cd / m ２ ) C: 0.8 (cd / m ２ ) ≦ Y

[0167] [Orientation Unevenness] The end of 300 m of coating of the long retardation film produced in the Examples and Comparative Examples was cut into a length of 1000 mm x width of 1340 mm. The film was set in a crossed Nicol arrangement with the length of the film aligned with the absorption axis of one of the polarizers, and observed from a polar angle of 0° with the axis perpendicular to the film surface as the reference. The alignment defect rate (light leakage points) observed at this time was evaluated according to the following criteria. <Evaluation Criteria> A: Fewer than 10 bright spots (white spots) were observed in the observed area. B: 10 or more but less than 100 bright spots (white spots) were observed in the observed area. C: 100 or more bright spots (white spots) were observed in the observed area.

[0168] [Adhesion] The adhesion between the liquid crystal layer and the support in the retardation films produced in Examples and Comparative Examples was evaluated by carrying out a cross-cut test according to JIS K5600-5-6, and the peelability from the support was evaluated according to the following criteria. <Evaluation criteria> A: Less than 1% of the liquid crystal layer peeled off. B: 1% or more but less than 50% of the liquid crystal layer peeled off. C: 50% or more of the liquid crystal layer peeled off.

[0169] [Crack Resistance] The first polarizing plates produced in the Examples and Comparative Examples were cut to 260 mm MD x 80 mm TD, and the retardation film side was attached to glass with adhesive SK-2057 (manufactured by Soken Chemical Co., Ltd.). The attached samples were heated in an oven at 125°C for 72 hours and then left in a room at 25°C and 60% humidity for 300 hours, after which the occurrence of cracks was evaluated according to the following criteria. <Evaluation Criteria> A: No cracks of 1 mm or more in length occurred within the surface. B: 1 to 20 cracks of 1 mm or more in length occurred within the surface. C: 21 or more cracks of 1 mm or more in length occurred within the surface.

[0170] For the long retardation films produced in Examples and Comparative Examples, the monomer compounds (two types) contained in the resin composition used to form the support, the bond type and average polymerization degree during copolymerization, the optical properties and thickness of the support, the main liquid crystal compound (maximum content of liquid crystal compound) contained in the liquid crystal composition used to form the liquid crystal layer (positive C plate), the optical properties of the liquid crystal layer, ΔSP value, ΔSP (A), the value of the above-mentioned formula (1), and the product of the photoelastic constant (unit: Pa) and the thickness (unit: μm) are shown in Tables 2 and 3 below.

[0171]

[0172]

[0173] As shown in Tables 2 and 3, the photoelastic constant of the support is 30×10 －１２ It was found that when a retardation film having a photoelastic constant of more than 30×10 Pa was used, uneven mounting occurred (Comparative Examples 1 to 4). －１２ Pa or less, or the product of the photoelastic constant and the thickness is 2000 × 10 －１２It was found that the occurrence of mounting unevenness could be suppressed when a retardation film with a viscosity of Pa·μm or less was used (Examples 1 to 27). In particular, the results of Examples 1 to 20 (particularly the comparison of Examples 14, 17, and 18 with other Examples) showed that alignment unevenness was suppressed when the ΔSP value was 8.8 or more, and that alignment unevenness was further suppressed when the ΔSP value was 9.5 or more. Furthermore, a comparison of Example 1 with Example 12 showed that oblique light leakage was suppressed when the retardation in the thickness direction of the liquid crystal layer exhibited reverse wavelength dispersion. Furthermore, a comparison of Example 2 with Example 13 showed that oblique light leakage was suppressed when the support was a positive A plate. Furthermore, a comparison of Example 1 with Example 15 showed that the adhesion between the support and the liquid crystal layer was improved when the liquid crystal composition contained a boronic acid monomer having a polymerizable group and a boronic acid group represented by the following formula (B). Furthermore, a comparison of Example 2 with Example 16 showed that when the photoelastic constant of the support was 25×10 －１２ It was found that the occurrence of mounting unevenness was further suppressed when the elastic modulus was equal to or less than Pa. Furthermore, a comparison of Examples 2, 11, and 21 to 25 revealed that the crack resistance was excellent when the polymer contained in the polymer film (support) had a product of Nw and ΔSP(A) (Nw × ΔSP(A)) in the above formula (1) of 700 or more, and that the crack resistance was even more excellent when this product was 900 or more.

Claims

1. A retardation film having a support showing in-plane retardation with inverse wavelength dispersion and a liquid crystal layer directly laminated on the support, wherein the support is a polymer film that has been stretched in at least one in-plane direction, the liquid crystal layer is a positive C-plate formed by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound, and the photoelastic constant of the support is 30×10 －１２ Pa or less. Retardation film.

2. The retardation film according to claim 1, wherein the difference between the solubility parameter of the polymer contained in the polymer film and the solubility parameter of the liquid crystal compound having the highest content among the liquid crystal compounds contained in the liquid crystal composition is 8.8 or more.

3. The retardation film according to claim 1, wherein the polymer contained in the polymer film is a polycarbonate or a polyester.

4. The photoelastic constant of the support is 25 × 10 －１２ Pa or less. The retardation film according to claim 1.

5. The retardation film according to claim 1, wherein the difference between the solubility parameter of the polymer contained in the polymer film and the solubility parameter of the liquid crystal compound having the highest content among the liquid crystal compounds contained in the liquid crystal composition is 9.5 or more.

6. The retardation film according to claim 1, wherein the support is a positive A plate.

7. The retardation film according to claim 1, wherein the retardation in the thickness direction of the liquid crystal layer exhibits inverse wavelength dispersion.

8. The retardation film according to claim 1, wherein the liquid crystal composition further contains a boronic acid monomer having a polymerizable group and a boronic acid group represented by the following formula (B). In the formula (B), * represents a bonding position. R １ and R ２ each independently represents a hydrogen atom, an aliphatic hydrocarbon group which may have a substituent, an aryl group which may have a substituent, or a heterocyclic group which may have a substituent, and R １ and R ２ may be linked to each other to form a ring.

9. The retardation film according to claim 1, wherein the polymer contained in the polymer film satisfies the following formula (1): Nw × ΔSP(A) ≥ 700 (1) Here, in the formula (1), Nw represents the weight average degree of polymerization of the polymer contained in the polymer film. ΔSP(A) represents the difference between the solubility parameter of the polymer contained in the polymer film and the solubility parameter of acetone.

10. A retardation film having a support that exhibits reverse wavelength dispersion in in-plane retardation and a liquid crystal layer directly laminated on the support, wherein the support is a polymer film that has been stretched in at least one in-plane direction, the liquid crystal layer is a positive C-plate formed by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound, and the product of the photoelastic constant (unit: Pa) and the thickness (unit: μm) of the support is 2000×10 －１２ Pa·μm or less. The retardation film.

11. A polarizing plate having the retardation film according to any one of claims 1 to 10 and a polarizer.

12. The polarizing plate according to claim 11, wherein the absorption axis of the polarizer and the slow axis of the support of the retardation film are orthogonal or parallel.

13. The polarizing plate according to claim 11, wherein the absorption axis of the polarizer and the slow axis of the support of the retardation film are parallel.

14. An image display device having the polarizing plate according to claim 11.

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