Optically anisotropic film, circular polarizing plate, display device

Abstract

The present invention provides an optically anisotropic film, a circularly polarizing plate, and a display device that exhibit reverse wavelength dispersion and have an Nz coefficient of approximately 0.50 (0.40 to 0.60). The optically anisotropic film of the present invention is formed using a lyotropic liquid crystal composition containing a non-coloring rod-shaped compound and a non-coloring plate-shaped compound. When the optically anisotropic film is irradiated with linearly polarized light from the normal direction of the film while changing the orientation of the linearly polarized light to obtain an ultraviolet-visible absorption spectrum, the first direction is defined as the direction in which the absorbance of the rod-shaped compound at the maximum absorption wavelength in the wavelength range of 230 to 400 nm is the highest, and the second direction is defined as the direction in which the absorbance of the plate-shaped compound at the maximum absorption wavelength in the wavelength range of 230 to 400 nm is the highest. The first direction and the second direction are orthogonal to each other, the maximum absorption wavelength of the rod-shaped compound in the wavelength range of 230 to 400 nm is shorter than the maximum absorption wavelength of the plate-shaped compound in the wavelength range of 230 to 400 nm, and the Nz of the plate-shaped compound represented by the formula (N) is: P Is negative. Formula (N)Nz P =(nx P ‑nz P ) / (nx P ‑ny P )

Description

Technical Field

[0001] The present invention relates to an optically anisotropic film, a circular polarizer and a display device. Background Art

[0002] Phase difference films (optically anisotropic films) having refractive index anisotropy are used in various applications such as antireflection films for display devices and optical compensation films for liquid crystal display devices.

[0003] For example, Patent Document 1 proposes a biaxial optically anisotropic film formed using a composition exhibiting lyotropic liquid crystal properties. Biaxiality here means that the refractive index nx in the slow axis direction, the refractive index ny in the fast axis direction, and the refractive index nz in the thickness direction of the optically anisotropic film satisfy the relationship nx>nz>ny.

[0004] Previous technical literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application No. 2012-500316 Summary of the Invention

[0007] Technical issues to be solved by the invention

[0008] On the other hand, in recent years, optically anisotropic films are required to exhibit reverse wavelength dispersion.

[0009] The present inventors have studied the properties of the biaxial optically anisotropic film described in Patent Document 1 and have found that the film does not exhibit reverse wavelength dispersion, indicating that further improvement is required.

[0010] In view of the above-mentioned actual situation, an object of the present invention is to provide an optically anisotropic film that exhibits reverse wavelength dispersion and has an Nz coefficient of approximately 0.50 (0.40 to 0.60).

[0011] Furthermore, another object of the present invention is to provide a circular polarizing plate and a display device.

[0012] Means for solving technical problems

[0013] The present inventors have conducted intensive studies on the problems of the conventional technology and have found that the above-mentioned problems can be solved by the following configuration.

[0014] (1) An optically anisotropic film formed using a lyotropic liquid crystal composition containing a non-coloring rod-shaped compound and a non-coloring plate-shaped compound, wherein:

[0015] When measuring an ultraviolet-visible absorption spectrum by irradiating linearly polarized light from the normal direction of the optically anisotropic film while changing the orientation of the linearly polarized light, the direction in which the absorbance of the rod-shaped compound at the maximum absorption wavelength in the wavelength range of 230 to 400 nm is the highest is defined as a first direction, and the direction in which the absorbance of the plate-shaped compound at the maximum absorption wavelength in the wavelength range of 230 to 400 nm is the highest is defined as a second direction, and the first direction and the second direction are orthogonal to each other.

[0016] The maximum absorption wavelength of the rod-shaped compound in the wavelength range of 230 to 400 nm is smaller than the maximum absorption wavelength of the plate-shaped compound in the wavelength range of 230 to 400 nm.

[0017] Nz represented by the formula (N) described below in the plate-like compound P is negative.

[0018] Formula (N)Nz P =(nx P -nz P ) / (nx P -ny P )

[0019] (2) The optically anisotropic film according to (1), wherein Nz P It is -0.45 to -0.10.

[0020] (3) The optically anisotropic film according to (1) or (2), wherein Nz P It is -0.30 to -0.15.

[0021] (4) An optically anisotropic film formed using a lyotropic liquid crystal composition containing a non-coloring rod-shaped compound and a non-coloring plate-shaped compound, wherein:

[0022] When measuring an ultraviolet-visible absorption spectrum by irradiating linearly polarized light from the normal direction of the optically anisotropic film while changing the orientation of the linearly polarized light, the direction in which the absorbance of the rod-shaped compound at the maximum absorption wavelength within the wavelength range of 230 to 400 nm is the highest is defined as a first direction, and the direction in which the absorbance of the plate-shaped compound at the maximum absorption wavelength within the wavelength range of 230 to 400 nm is the highest is defined as a second direction, the first direction and the second direction being orthogonal to each other.

[0023] The maximum absorption wavelength of the rod-shaped compound in the wavelength range of 230 to 400 nm is smaller than the maximum absorption wavelength of the plate-shaped compound in the wavelength range of 230 to 400 nm.

[0024] Nz represented by the formula (N1) described later in the plate-like compound P1 is negative.

[0025] Formula (N1)Nz P1 =(nx P1 -nz P1 ) / (nx P1 -ny P1 )

[0026] (5) The optically anisotropic film according to (4), wherein Nz P1 It is -0.45 to -0.10.

[0027] (6) The optically anisotropic film according to (4) or (5), wherein Nz P1 It is -0.30 to -0.15.

[0028] (7) The optically anisotropic film according to any one of (1) to (6), wherein both the rod-shaped compound and the plate-shaped compound are lyotropic liquid crystalline compounds.

[0029] (8) The optically anisotropic film according to any one of (1) to (7), wherein the rod-shaped compound and the plate-shaped compound have a hydrophilic group.

[0030] (9) The optically anisotropic film according to any one of (1) to (8), wherein the rod-shaped compound is a polymer having a repeating unit represented by the formula (X) described below.

[0031] (10) The optically anisotropic film according to any one of (1) to (9), wherein the plate-like compound is a compound represented by the formula (Y) described below.

[0032] (11) A circular polarizer having:

[0033] The optically anisotropic film according to any one of (1) to (10); and

[0034] Polarizer.

[0035] (12) The circular polarizing plate according to (11), wherein an angle formed by an in-plane slow axis of the optically anisotropic film and an absorption axis of the polarizer is within a range of 45±5°.

[0036] A display device comprising:

[0037] The circular polarizing plate described in (11) or (12); and

[0038] Display components.

[0039] (14) The display device according to (13), wherein the display element is an organic electroluminescent display element.

[0040] Effects of the Invention

[0041] According to the present invention, there can be provided an optically anisotropic film which exhibits reverse wavelength dispersion and has an Nz coefficient of approximately 0.50 (0.40 to 0.60).

[0042] Furthermore, according to the present invention, a circular polarizing plate and a display device can also be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram for explaining the structure of the optically anisotropic film of the present invention.

[0044] Figure 2 This is a schematic diagram for explaining the optical properties of a non-coloring rod-shaped compound and a non-coloring plate-shaped compound.

[0045] Figure 3 It is a schematic diagram for explaining the optical characteristics of the optically anisotropic film of the present invention.

[0046] Figure 4 This is a graph showing a comparison of the wavelength dispersion of the extraordinary light refractive index ne and the ordinary light refractive index no of the optically anisotropic film of the present invention showing reverse wavelength dispersion.

[0047] Figure 5 This is a schematic diagram for explaining a method for obtaining an ultraviolet-visible absorption spectrum by irradiating a film with linearly polarized light from the normal direction of the optically anisotropic film. DETAILED DESCRIPTION

[0048] Hereinafter, the present invention will be described in detail.

[0049] In addition, in this specification, the numerical range expressed with "to" means a range including the numerical values ​​described before and after "to" as the lower limit and the upper limit.

[0050] Furthermore, unless otherwise specified, the slow axis and the fast axis are defined at a wavelength of 550 nm. That is, unless otherwise specified, for example, the slow axis direction refers to the direction of the slow axis at a wavelength of 550 nm.

[0051] In the present invention, Re(λ) and Rth(λ) represent the in-plane retardation and the retardation in the thickness direction at a wavelength λ, respectively. Unless otherwise specified, the wavelength λ is 550 nm.

[0052] In the present invention, Re(λ) and Rth(λ) are values ​​measured at a wavelength of λ in AxoScan OPMF-1 (manufactured by Opto Science, Inc.). The average refractive index ((nx+ny+nz) / 3) and film thickness (d (μm)) are input into AxoScan to calculate

[0053] Slow axis direction (°)

[0054] Re(λ)=R0(λ)

[0055] Rth(λ)=((nx+ny) / 2-nz)×d.

[0056] In addition, R0(λ) is displayed as a numerical value calculated using AxoScan OPMF-1 and represents Re(λ).

[0057] In this specification, the refractive indices nx, ny, and nz are measured using an Abbe refractometer (NAR-4T, manufactured by ATAGO CO., LTD.) using a sodium lamp (λ = 589 nm) as a light source. Furthermore, when measuring wavelength dependence, measurements can be performed using a multi-wavelength Abbe refractometer DR-M2 (manufactured by ATAGO CO., LTD.) in combination with an interference filter.

[0058] Alternatively, values ​​from the Polymer Handbook (John Wiley & Sons, Inc.) and various optical film catalogs may be used. Examples of average refractive index values ​​for major optical films include cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), and polystyrene (1.59).

[0059] Also, in this specification, the Nz coefficient is a value given by Nz=(nx-nz) / (nx-ny).

[0060] When calculating the Nz coefficient of the optically anisotropic film, nx is the refractive index in the slow axis direction of the optically anisotropic film in the plane, ny is the refractive index in the fast axis direction of the optically anisotropic film in the plane, and nz is the refractive index in the thickness direction of the optically anisotropic film in the Nz coefficient of the optically anisotropic film.

[0061] In addition, nx, ny, and nz when calculating the Nz coefficient are the respective refractive indices at a wavelength of 550 nm.

[0062] In this specification, "visible light" refers to light with a wavelength of 400 to 700 nm, and "ultraviolet light" refers to light with a wavelength of 10 nm or more and less than 400 nm.

[0063] Furthermore, in this specification, references to angle relationships (e.g., "perpendicular," "parallel," etc.) include the permissible error ranges within the technical field of the present invention. For example, references to angles within a range of ±5° from a strict angle preferably indicate an error within a range of ±3° from a strict angle.

[0064] The bonding direction of the divalent group (e.g., -COO-) described in this specification is not particularly limited. For example, when L in XLY is -COO-, if the position bonding to the X side is *1 and the position bonding to the Y side is *2, then L can be *1-O-CO-*2 or *1-CO-O-*2.

[0065] In the optically anisotropic film of the present invention, the rod-shaped compound and plate-shaped compound described below are arranged so as to exhibit predetermined optical characteristics.

[0066] The composition for forming an optically anisotropic film is a composition showing lyotropic liquid crystal properties, and forms an alignment state along a predetermined shear direction when forming an optically anisotropic film. Specifically, Figure 1 As shown, when the composition is applied to a support 10 and sheared along the x-axis, the rod-shaped compound 12 serving as the main component on the support 10 is arranged with its molecular axis (the direction in which the rod-shaped compound 12 extends) along the x-axis. Furthermore, the plate-shaped compound 14 has a ring structure inside and has a plate-like structure as a whole. Therefore, as Figure 1 As shown, the plurality of plate-like compounds 14 are arranged so that the surfaces of the plate-like structures face each other (in other words, so that the ring structures inside the compounds face each other). Furthermore, the columnar aggregate formed by the association of the plate-like compounds 14 is arranged along the molecular axis of the rod-like compound 12, which is the main component, along the extension direction of the aggregate. In this case, as shown in FIG. Figure 1 As shown, the plate-like compound 14 is arranged so as to stand upright with respect to the support 10 . That is, the plate-like compound 14 is arranged so that the major axis direction is along the normal direction (z-axis direction) of the support 10 .

[0067] As described later, within the plane of the optically anisotropic film, the direction in which the rod-shaped compound has the highest absorbance at the maximum absorption wavelength in the range of 230 to 400 nm is defined as the first direction, and the direction in which the plate-shaped compound has the highest absorbance at the maximum absorption wavelength in the range of 230 to 400 nm is defined as the second direction. The first direction and the second direction are perpendicular to each other. This optical characteristic shows Figure 1 More specifically, within the surface of the optically anisotropic film, as shown in FIG. Figure 1 As shown, the direction of the highest absorbance of the rod-shaped compound 12 is the x-axis direction, and the direction of the highest absorbance of the plate-shaped compound 14 is the y-axis direction. Figure 1 The arrangement relationship of the rod-shaped compound 12 and the plate-shaped compound 14 is shown.

[0068] Furthermore, the Nz coefficient of the optically anisotropic film P described later is negative. This optical characteristic is determined by Figure 1Therefore, the above optical properties are derived from the fact that the rod-shaped compound 12 is arranged upright. Figure 1 The arrangement relationship of the rod-shaped compound 12 and the plate-shaped compound 14 is shown.

[0069] like Figure 1 As shown, when the molecular axis of the rod-shaped compound 12 is arranged along the x-axis direction, the refractive index nx in the x-axis direction, the refractive index ny in the y-axis direction, and the refractive index nz in the z-axis direction of the rod-shaped compound 12 are as follows: Figure 2 As shown, nx is the largest. And, as Figure 1 As shown, when the plate-like compound 14 is disposed, the refractive index nx in the x-axis direction, the refractive index ny in the y-axis direction, and the refractive index nz in the z-axis direction of the plate-like compound 14 are as follows: Figure 2 As shown, nz is the largest. The refractive index nx in the x-axis direction, the refractive index ny in the y-axis direction, and the refractive index nz in the z-axis direction of the optically anisotropic film depend on the refractive index nx in the x-axis direction, the refractive index ny in the y-axis direction, and the refractive index nz in the z-axis direction of each component contained in the optically anisotropic film. Therefore, as shown in FIG. Figure 1 As shown, when the rod-shaped compound 12 and the plate-shaped compound 14 are arranged, the refractive index nx in the x-axis direction, the refractive index ny in the y-axis direction, and the refractive index nz in the z-axis direction of the optically anisotropic film are as follows: Figure 3 As shown, Figure 1 The x-axis direction is the slow axis, and the refractive index nx, refractive index ny, and refractive index nz of the optically anisotropic film satisfy the relationship nx>nz>ny. In other words, the predetermined Nz coefficient requirement (0.40 to 0.60) is easily satisfied.

[0070] Furthermore, in the present invention, the maximum absorption wavelength of the rod-shaped compound in the wavelength range of 230 to 400 nm is shorter than the maximum absorption wavelength of the plate-shaped compound in the wavelength range of 230 to 400 nm. In other words, the rod-shaped compound has a maximum absorption wavelength at a shorter wavelength, while the plate-shaped compound has a maximum absorption wavelength at a longer wavelength. Figure 1 As shown, the rod-shaped compound 12 has its absorption axis aligned along the x-axis, and the plate-shaped compound 14 has its absorption axis aligned along the y-axis. Figure 4 As shown, since the refractive index of nx decreases earlier than the refractive index of ny, the refractive index of nx decreases more slowly than the refractive index of ny in the region indicated by the arrow, thereby achieving reverse wavelength dispersion.

[0071] exist Figure 1 In order to simplify the description, only two rod-shaped compounds 12 and four plate-shaped compounds 14 are shown. However, the number of rod-shaped compounds and plate-shaped compounds in the optically anisotropic film is not limited to Figure 1 way.

[0072] The optically anisotropic film of the present invention (hereinafter also simply referred to as "optically anisotropic film") is formed using a lyotropic liquid crystal composition (hereinafter also simply referred to as "composition") containing a non-coloring rod-shaped compound and a non-coloring plate-shaped compound.

[0073] Hereinafter, the materials contained in the composition will be described in detail first, and then the optically anisotropic film formed using the composition will be described in detail.

[0074] (Rod-shaped compound)

[0075] The composition contains a non-coloring rod-shaped compound (hereinafter also referred to simply as a "rod-shaped compound"). As described above, the rod-shaped compound is easily oriented in a predetermined direction.

[0076] Non-coloring means showing no absorption in the visible light region. More specifically, when measuring the UV-visible absorption spectrum of a solution containing the rod-shaped compound dissolved at a concentration such that the absorbance at the maximum absorption wavelength in the ultraviolet region (230-400 nm) is 1.0, the absorbance in the visible light region (wavelength 400-700 nm) is 0.1 or less.

[0077] The rod-shaped compound preferably exhibits lyotropic liquid crystal properties. Specifically, the rod-shaped compound is preferably a non-coloring lyotropic liquid crystal rod-shaped compound. Lyotropic liquid crystal properties refer to the property of undergoing a phase transition from an isotropic phase to a liquid crystal phase when dissolved in a solvent in a solution state by changes in temperature and concentration.

[0078] The rod-shaped compound is preferably water-soluble from the viewpoint of easily controlling the expression of liquid crystallinity. A water-soluble rod-shaped compound is one that dissolves at least 1% by mass, preferably at least 5% by mass, in water.

[0079] Rod-shaped compounds are compounds having ring structures (aromatic rings and non-aromatic rings) connected one-dimensionally by single bonds or divalent linking groups, and represent a group of compounds that have the property of being oriented in a solvent with their major axes aligned parallel to each other.

[0080] The rod-shaped compound preferably has a maximum absorption wavelength in the range of 300 nm or less. In other words, the rod-shaped compound preferably has a maximum absorption peak in the range of 300 nm or less.

[0081] The maximum absorption wavelength of the rod-shaped compound is the wavelength at which the absorbance reaches a maximum value in the rod-shaped compound's absorption spectrum (measurement range: wavelength range of 230 to 400 nm). If the absorbance spectrum of the rod-shaped compound has multiple maximum values, the wavelength with the longest wavelength in the measurement range is selected.

[0082] Among them, from the viewpoint of excellent effects of the present invention, the rod-shaped compound preferably has a maximum absorption wavelength in the range of 230 to 300 nm, and more preferably has a maximum absorption wavelength in the range of 250 to 290 nm.

[0083] The method for measuring the maximum absorption wavelength is as follows.

[0084] The rod-shaped compound (5 to 50 mg) was dissolved in pure water (1000 ml), and the absorption spectrum of the resulting solution was measured using a spectrophotometer (MPC-3100 (manufactured by SHIMADZU)).

[0085] In the present invention, the maximum absorption wavelength of the rod-shaped compound in the wavelength range of 230 to 400 nm is shorter than the maximum absorption wavelength of the plate-shaped compound described later in the wavelength range of 230 to 400 nm.

[0086] The difference between the maximum absorption wavelength of the rod-shaped compound and the maximum absorption wavelength of the plate-shaped compound is not particularly limited, but is preferably 50 nm or more, and more preferably 70 nm or more.

[0087] As mentioned above, the maximum absorption wavelength of a rod-shaped compound refers to the wavelength at which the absorbance reaches a maximum value in the rod-shaped compound's absorption spectrum (measurement range: wavelength range of 230 to 400 nm). If the absorbance spectrum of the rod-shaped compound has multiple maximum values, the wavelength with the longest wavelength in the measurement range is selected.

[0088] As described below, the maximum absorption wavelength of a plate-like compound refers to the wavelength at which the absorbance reaches a maximum value in the plate-like compound's absorption spectrum (measurement range: wavelength range of 230 to 400 nm). If the absorbance spectrum of the plate-like compound has multiple maximum values, the wavelength with the longest wavelength in the measurement range is selected.

[0089] From the viewpoint of further improving the effects of the present invention, the wavelength dispersion D of the rod-shaped compound represented by the formula (R) R It is preferably 1.05 or more and less than 1.20. As described later, the wavelength dispersion D R These are optical properties of an optically anisotropic film of a rod-shaped compound, and correspond to the optical properties exhibited by the rod-shaped compound in the optically anisotropic film.

[0090] Formula (R) wavelength dispersion D R =Re(450) R / Re(550) R

[0091] Re(450) RRe(550) represents the in-plane retardation at a wavelength of 450 nm of an optically anisotropic film R formed using a mixed solution R obtained by mixing 10 parts by mass of a rod-shaped compound with 90 parts by mass of water. R It shows the in-plane retardation of the optically anisotropic film R at a wavelength of 550 nm.

[0092] As described above, the wavelength dispersion D of the rod-shaped compound represented by the formula (R) R The relationship of the in-plane retardation of the optically anisotropic film R formed using the rod-shaped compound is shown.

[0093] The optically anisotropic film R was prepared by applying the mixed solution R onto a glass substrate using a No. 4 wire rod (moving speed: 100 cm / s) and then drying the mixture naturally at room temperature (20° C.) to prepare an optically anisotropic film R (film thickness: approximately 240 nm).

[0094] The rod-shaped compound contained in the mixed solution R is the same as the rod-shaped compound in the composition.

[0095] In addition, the wavelength dispersion D R The wavelength dispersion D P Different values ​​are preferred.

[0096] Nz coefficient of optically anisotropic film R (Nz R ) is usually 1.

[0097] The Nz coefficient of the optically anisotropic film R is given by Nz R =(nx R -nz R ) / (nx R -ny R ) is the value given by .

[0098] nx R is the refractive index in the slow axis direction of the optically anisotropic film R, ny R is the refractive index in the fast axis direction of the optically anisotropic film R, nz R nx is the refractive index in the thickness direction of the optically anisotropic film R. R 、ny R and nz R are the refractive indices at a wavelength of 550 nm.

[0099] From the viewpoint of achieving more excellent effects of the present invention, the rod-shaped compound preferably has a hydrophilic group.

[0100] The rod-shaped compound may have only one hydrophilic group or may have a plurality of hydrophilic groups.

[0101] Examples of the hydrophilic group include an acid group or a salt thereof, an onium base, a hydroxyl group, a sulfoneamide group (H2N-SO2-), and a polyoxyalkylene group. Among them, an acid group or a salt thereof is preferred.

[0102] The acid group or its salt will be described in detail later.

[0103] Onium bases are groups derived from onium salts, and examples thereof include ammonium bases (*-N + (R Z )4A - ), phosphonium base (*-P + (R Z )4A - ) and sulfonium base (*-S + (R Z )2A - ). R Z A represents independently a hydrogen atom, an alkyl group, an aryl group, and a heteroaryl group. - Indicates an anion (eg, a halogen ion). * Indicates a bonding position.

[0104] Examples of the polyoxyalkylene group include: Z -(OL Z ) n -* represents a group. Z As mentioned above. Z represents an alkylene group. * represents a bonding position.

[0105] Examples of the acid group or its salt include a sulfonic acid group (-SO3H) or its salt (-SO3 - M + . M + represents a cation. ) and a carboxyl group (-COOH) or a salt thereof (-COO - M + . M + represents a cation. ), from the viewpoint of further improving the effects of the present invention, a sulfonic group or a salt thereof is preferred.

[0106] The salts mentioned above are salts in which the hydrogen ions of an acid are replaced by other cations such as metals. In other words, the salts of acid groups are salts in which the hydrogen ions of acid groups such as -SO3H groups are replaced by other cations.

[0107] Examples of cations in salts of acid groups (for example, cations in salts of sulfonic groups and carboxyl groups) include Na + , K + 、Li + , Rb + 、Cs + 、Ba 2+ , Ca 2+ Mg 2+ 、Sr2+ , Pb 2+ 、Zn 2+ 、La 3+ 、Ce 3+ 、Y 3+ 、Yb 3+ 、Gd 3+ or Zr 4+ Among them, from the viewpoint of the better effect of the present invention, alkali metal ions are preferred, and Na + or Li + , further preferably Li + .

[0108] From the viewpoint of achieving more excellent effects of the present invention, the rod-shaped compound is preferably a polymer having a repeating unit represented by formula (X).

[0109] [Chemical Formula 1]

[0110]

[0111] R x1 represents a divalent aromatic ring group having a substituent containing a hydrophilic group, a divalent non-aromatic ring group having a substituent containing a hydrophilic group, or a group represented by formula (X1): In formula (X1), * represents a bonding position.

[0112] Formula (X1)*-R x3 -L x3 -R x4 -*

[0113] R x3 and R x4 Each independently represents a divalent aromatic ring group which may have a substituent containing a hydrophilic group, or a divalent non-aromatic ring group which may have a substituent containing a hydrophilic group, R x3 and R x4 At least one of them represents a divalent aromatic ring group having a substituent containing a hydrophilic group, or a divalent non-aromatic ring group having a substituent containing a hydrophilic group.

[0114] L x3 represents a single bond, -O-, -S-, an alkylene group, an alkenylene group, or an alkynylene group.

[0115] By R x1 The divalent aromatic ring group and the divalent non-aromatic ring group represented by have a substituent containing a hydrophilic group.

[0116] Examples of the hydrophilic group contained in the substituent containing a hydrophilic group include the above-mentioned groups, and an acid group or a salt thereof is preferred.

[0117] As the substituent containing a hydrophilic group, a group represented by formula (H) is preferred. In formula (H), * represents a bonding position.

[0118] Formula (H)R H -L H -*

[0119] R H The hydrophilic group is defined as above.

[0120] L H represents a single bond or a divalent linking group. The divalent linking group is not particularly limited, and examples thereof include divalent hydrocarbon groups (e.g., divalent aliphatic hydrocarbon groups such as alkylene groups having 1 to 10 carbon atoms, alkenylene groups having 1 to 10 carbon atoms, and alkynylene groups having 1 to 10 carbon atoms, and divalent aromatic hydrocarbon groups such as arylene groups), divalent heterocyclic groups, -O-, -S-, -NH-, -CO-, or groups formed by combining these groups (e.g., -CO-O-, -O-divalent hydrocarbon group-, -(O-divalent hydrocarbon group) m -O- (m represents an integer of 1 or greater) and -divalent hydrocarbon group -O-CO-, etc.).

[0121] The number of the substituents containing a hydrophilic group possessed by the divalent aromatic ring group is not particularly limited, but is preferably 1 to 3, more preferably 1, from the viewpoint of further improving the effects of the present invention.

[0122] The number of the substituents containing a hydrophilic group possessed by the divalent non-aromatic ring group is not particularly limited, but is preferably 1 to 3, more preferably 1, from the viewpoint of further improving the effects of the present invention.

[0123] Composed of R x1 The aromatic ring of the divalent aromatic ring group having a substituent containing a hydrophilic group may be a monocyclic structure or a polycyclic structure.

[0124] As the aromatic ring constituting the above-mentioned divalent aromatic ring group, for example, an aromatic hydrocarbon ring or an aromatic heterocyclic ring can be mentioned. x1 Examples of the hydrophilic group include a divalent aromatic hydrocarbon ring group having a substituent containing a hydrophilic group and a divalent aromatic heterocyclic group having a substituent containing a hydrophilic group.

[0125] Examples of the aromatic hydrocarbon ring include a benzene ring and a naphthalene ring.

[0126] Examples of the structure of the divalent aromatic hydrocarbon ring group portion of the divalent aromatic hydrocarbon ring group having only a substituent containing a hydrophilic group include the following groups: * represents a bonding position.

[0127] [Chemical Formula 2]

[0128]

[0129] Examples of the aromatic heterocyclic ring include a pyridine ring, a thiophene ring, a pyrimidine ring, a thiazole ring, a furan ring, a pyrrole ring, an imidazole ring, and an indole ring.

[0130] Examples of the structure of the divalent aromatic heterocyclic group portion of the divalent aromatic heterocyclic group having only a substituent containing a hydrophilic group include the following groups: * represents a bonding position.

[0131] [Chemical Formula 3]

[0132]

[0133] Composed of R x1 The non-aromatic ring of the divalent non-aromatic ring group having a substituent containing a hydrophilic group may be a monocyclic structure or a polycyclic structure.

[0134] Examples of the non-aromatic ring constituting the divalent non-aromatic ring group include aliphatic rings and non-aromatic heterocyclic rings. From the perspective of achieving a more excellent effect of the present invention, aliphatic rings are preferred, cycloalkane is more preferred, and cyclohexane is further preferred. x1 Examples of the group include a divalent aliphatic ring group having a substituent containing a hydrophilic group and a divalent non-aromatic heterocyclic group having a substituent containing a hydrophilic group. A divalent cycloalkylene group having a substituent containing a hydrophilic group is preferred.

[0135] The aliphatic ring may be a saturated aliphatic ring or an unsaturated aliphatic ring.

[0136] Examples of the structure of the divalent aliphatic ring group portion of the divalent aliphatic ring group having only a substituent containing a hydrophilic group include the following groups: * represents a bonding position.

[0137] [Chemical Formula 4]

[0138]

[0139] The hetero atom contained in the non-aromatic heterocyclic ring is not particularly limited, and examples thereof include an oxygen atom, a nitrogen atom, and a sulfur atom.

[0140] The number of heteroatoms contained in the non-aromatic heterocyclic ring is not particularly limited, and examples thereof include 1 to 3 heteroatoms.

[0141] Examples of the structure of the divalent non-aromatic heterocyclic group portion of the divalent non-aromatic heterocyclic group having only a substituent containing a hydrophilic group include the following groups: * represents a bonding position.

[0142] [Chemical Formula 5]

[0143]

[0144] By R x1 The divalent aromatic ring group having a substituent containing a hydrophilic group and the divalent non-aromatic ring group having a substituent containing a hydrophilic group represented by may have a substituent other than the substituent containing a hydrophilic group.

[0145] The substituent is not particularly limited, and examples thereof include alkyl groups, alkenyl groups, alkynyl groups, aryl groups, amino groups, alkoxy groups, aryloxy groups, aromatic heterocyclic oxy groups, acyl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, acyloxy groups, acylamino groups, alkoxycarbonylamino groups, aryloxycarbonylamino groups, alkylthio groups, arylthio groups, aromatic heterocyclic thio groups, ureido groups, halogen atoms, cyano groups, hydrazino groups, heterocyclic groups (e.g., heteroaryl groups), silyl groups, and combinations thereof. The above substituents may be further substituted with substituents.

[0146] R x3 and R x4 Each independently represents a divalent aromatic ring group which may have a substituent containing a hydrophilic group, or a divalent non-aromatic ring group which may have a substituent containing a hydrophilic group, R x3 and R x4 At least one of them represents a divalent aromatic ring group having a substituent containing a hydrophilic group, or a divalent non-aromatic ring group having a substituent containing a hydrophilic group.

[0147] By R x3 and R x4 The definition of the substituent containing a hydrophilic group which the divalent aromatic ring group represented may have is as described above.

[0148] And, the composition is composed of R x3 and R x4 The definition of the aromatic ring of the divalent aromatic ring group which may have a substituent containing a hydrophilic group is the same as that of the above-mentioned aromatic ring group consisting of R x1 The aromatic ring of the divalent aromatic ring group having a substituent containing a hydrophilic group has the same definition as that of .

[0149] By R x3 and R x4 The definition of the substituent containing a hydrophilic group which the divalent non-aromatic ring group represented may have is as described above.

[0150] And, the composition is composed of R x3 and R x4 The definition of the non-aromatic ring of the divalent non-aromatic ring group which may have a substituent containing a hydrophilic group is the same as that of the above-mentioned non-aromatic ring group consisting of R x1The non-aromatic ring of the divalent non-aromatic ring group having a substituent containing a hydrophilic group is defined in the same manner.

[0151] R x3 and R x4 At least one of represents a divalent aromatic ring group having a substituent containing a hydrophilic group or a divalent non-aromatic ring group having a substituent containing a hydrophilic group, R x3 and R x4 Both may represent a divalent aromatic ring group having a substituent containing a hydrophilic group or a divalent non-aromatic ring group having a substituent containing a hydrophilic group.

[0152] By R x3 and R x4 The definition of the divalent aromatic ring group having a substituent containing a hydrophilic group represented by R is the same as that of the above-mentioned x1 The divalent aromatic ring group having a substituent containing a hydrophilic group has the same definition as that shown in .

[0153] And, by R x3 and R x4 The definition of the divalent non-aromatic ring group having a substituent containing a hydrophilic group represented by R is the same as that of the above-mentioned x1 The divalent non-aromatic ring group having a substituent containing a hydrophilic group has the same definition as that shown in .

[0154] L x3 represents a single bond, -O-, -S-, an alkylene group, an alkenylene group, or an alkynylene group.

[0155] The number of carbon atoms in the alkylene group is not particularly limited, but is preferably 1 to 3, more preferably 1, from the viewpoint of further improving the effects of the present invention.

[0156] The number of carbon atoms in the alkenylene group and the alkynylene group is not particularly limited, but is preferably 2 to 5, more preferably 2 to 4, from the viewpoint of further improving the effects of the present invention.

[0157] R x2 represents a divalent non-aromatic ring group or a group represented by formula (X2): In formula (X2), * represents a bonding position.

[0158] Formula (X2)*-Z x1 -Z x2 -*

[0159] Z x1 and Z x2 Each independently represents a divalent non-aromatic ring group. * represents a bonding position.

[0160] Composed of R x2The non-aromatic ring of the divalent non-aromatic ring group represented by may be a monocyclic structure or a polycyclic structure.

[0161] Examples of the non-aromatic ring constituting the divalent non-aromatic ring group include aliphatic rings and non-aromatic heterocyclic rings. From the perspective of achieving a more excellent effect of the present invention, aliphatic rings are preferred, cycloalkane is more preferred, and cyclohexane is further preferred. x2 , a divalent aliphatic ring group and a divalent non-aromatic heterocyclic group can be mentioned, and a divalent cycloalkylene group is preferred.

[0162] The aliphatic ring may be a saturated aliphatic ring or an unsaturated aliphatic ring.

[0163] Examples of the divalent aliphatic ring group include the following groups: * represents a bonding position.

[0164] [Chemical Formula 6]

[0165]

[0166] The hetero atom contained in the non-aromatic heterocyclic ring is not particularly limited, and examples thereof include an oxygen atom, a nitrogen atom, and a sulfur atom.

[0167] The number of heteroatoms contained in the non-aromatic heterocyclic ring is not particularly limited, and examples thereof include 1 to 3 heteroatoms.

[0168] Examples of the divalent non-aromatic heterocyclic group include the following groups: * represents a bonding position.

[0169] [Chemical Formula 7]

[0170]

[0171] The divalent non-aromatic ring group may have a substituent. The type of the substituent is not particularly limited, and for example, the substituent may be substituted with R x1 Substituents other than the substituent containing a hydrophilic group that the divalent aromatic ring group having a substituent containing a hydrophilic group and the divalent non-aromatic ring group having a substituent containing a hydrophilic group represented by are exemplified as substituents other than the substituent containing a hydrophilic group that the divalent aromatic ring group having a substituent containing a hydrophilic group may have.

[0172] Z x1 and Z x2 Each independently represents a divalent non-aromatic ring group.

[0173] By Z x1 and Z x2 The definition of the divalent non-aromatic ring group represented by R is the same as that of the above x2 The divalent non-aromatic ring group represented by has the same definition.

[0174] L 1x and L2x Each independently represents -CONH-, -COO-, -O-, or -S-. Among them, -CONH- is preferred from the viewpoint of achieving more excellent effects of the present invention.

[0175] As the repeating unit represented by formula (X), a repeating unit represented by formula (X4) is preferred.

[0176] [Chemical Formula 8]

[0177]

[0178] The respective groups in formula (X4) are as defined above.

[0179] The content of the repeating unit represented by formula (X) contained in the polymer having the repeating unit represented by formula (X) is not particularly limited, but is preferably 60 mol% or more, more preferably 80 mol% or more, relative to all the repeating units in the polymer. As an upper limit, 100 mol% can be mentioned.

[0180] The molecular weight of the polymer having the repeating unit represented by formula (X) is not particularly limited, but the number of repeating units represented by formula (X) in the polymer is preferably 2 or more, preferably 10 to 100,000, and more preferably 100 to 10,000.

[0181] The number average molecular weight of the polymer having the repeating unit represented by formula (X) is not particularly limited, but is preferably 5,000 to 50,000, and more preferably 10,000 to 30,000.

[0182] The molecular weight distribution of the polymer having the repeating unit represented by formula (X) is not particularly limited, but is preferably 1.0 to 12.0, and more preferably 1.0 to 7.0.

[0183] Here, the number average molecular weight and molecular weight distribution in the present invention are values ​​measured by gel permeation chromatography (GPC).

[0184] Solvent (eluent): 20 mM phosphoric acid (pH 7.0) / acetonitrile = 4 / 1

[0185] Device Name: TOSOH HLC-8220GPC

[0186] Column: Connect three G6000PWxL, 4500PWxL, and G2500pWwL manufactured by Tosoh Corporation.

[0187] Column temperature: 40°C

[0188] Sample concentration: 2 mg / mL

[0189] Flow rate: 1 mL / min

[0190] Calibration curve: A calibration curve of 8 samples was used, ranging from polystyrene sulfonic acid (PSS) Mp = 891, 4.2k, 10.2k, 29.5k, 78.4k, 152k, 258k, 462k

[0191] (plate-like compound)

[0192] The composition contains a non-coloring plate-like compound (hereinafter, also simply referred to as a "plate-like compound").

[0193] The plate-like compound exhibits non-coloring properties.

[0194] Non-coloring means showing no absorption in the visible light region. More specifically, when measuring the UV-visible absorption spectrum of a solution obtained by dissolving the plate-like compound at a concentration such that the absorbance at the maximum absorption wavelength in the ultraviolet region (230-400 nm) is 1.0, it means that the absorbance in the visible light region (wavelength 400-700 nm) is 0.1 or less.

[0195] In addition, "plate-like compounds" refer to compounds in which aromatic rings (aromatic hydrocarbon rings and aromatic heterocycles, etc.) have a structure in which aromatic rings are two-dimensionally diffused through single bonds or appropriate connecting groups, and represent a group of compounds that have the property of forming columnar aggregates in a solvent by associating with each other through the planes in the compound.

[0196] The plate-like compound preferably exhibits lyotropic liquid crystal properties. That is, the plate-like compound is preferably a non-coloring lyotropic liquid crystal compound (non-coloring lyotropic liquid crystal plate-like compound).

[0197] The plate-like compound is preferably water-soluble from the viewpoint of easily controlling the expression of liquid crystallinity. A water-soluble plate-like compound is a plate-like compound that dissolves at least 1% by mass, preferably at least 5% by mass, in water.

[0198] The plate-like compound preferably has a maximum absorption wavelength in a range exceeding 300 nm. In other words, the plate-like compound preferably has a maximum absorption peak in a range exceeding 300 nm.

[0199] The maximum absorption wavelength of the plate-like compound is the wavelength at which the absorbance reaches a maximum value in the absorption spectrum of the plate-like compound (measurement range: wavelength range of 230 to 400 nm). If the absorbance spectrum of the plate-like compound has multiple maximum values, the wavelength with the longest wavelength in the measurement range is selected.

[0200] Among them, from the viewpoint of excellent effects of the present invention, the plate-like compound preferably has a maximum absorption wavelength in the range of 320 to 400 nm, and more preferably has a maximum absorption wavelength in the range of 330 to 360 nm.

[0201] The method for measuring the maximum absorption wavelength is as follows.

[0202] A specific compound (0.01 to 0.05 mmol) was dissolved in pure water (1000 ml), and the absorption spectrum of the resulting solution was measured using a spectrophotometer (MPC-3100 (manufactured by SHIMADZU)).

[0203] Nz represented by formula (N) of the plate-like compound P Among them, from the viewpoint of the better effect of the present invention, Nz P It is preferably -0.45 to -0.10, more preferably -0.30 to -0.15, and still more preferably -0.25 to -0.19.

[0204] As described later, Nz P and wavelength dispersion D described later P These are optical properties of the optically anisotropic film of the plate-like compound, and correspond to the optical properties exhibited by the plate-like compound in the optically anisotropic film.

[0205] Formula (N)Nz P =(nx P -nz P ) / (nx P -ny P )

[0206] About nx P , represents the refractive index in the slow axis direction of the in-plane optically anisotropic film P formed using a mixed solution P1 when the composition does not contain salt, and using a mixed solution P2 when the composition contains salt. The mixed solution P1 is obtained by mixing 10 parts by mass of a non-coloring plate-like compound with 90 parts by mass of water, and the mixed solution P2 is obtained by mixing 10 parts by mass of a non-coloring plate-like compound, 90 parts by mass of water, and a salt in an amount equal to the content ratio of the salt to the plate-like compound in the composition. P Indicates the refractive index in the fast axis direction of the optically anisotropic film P. P nx represents the refractive index in the thickness direction of the optically anisotropic film P. P 、ny P and nz P are the refractive indices at a wavelength of 550 nm.

[0207] That is, the optically anisotropic film P, when the composition does not contain salt, is formed using a mixed liquid P1 obtained by mixing 10 parts by mass of the plate-like compound and 90 parts by mass of water. When the composition contains salt, the optically anisotropic film is formed using a mixed liquid P2 obtained by mixing 10 parts by mass of the plate-like compound, 90 parts by mass of water, and an amount of salt having the same content ratio as the content ratio of the salt to the plate-like compound in the composition.

[0208] The optically anisotropic film P was prepared by coating the mixed solution P1 or P2 on a glass substrate using a No. 4 wire rod (moving speed: 100 cm / s) and then drying the mixture naturally at room temperature (20°C) to produce an optically anisotropic film P (film thickness: approximately 240 nm).

[0209] Furthermore, as described above, when the composition contains salt, the mixed solution P2 also contains a predetermined amount of salt. Specifically, the optically anisotropic film P is produced by adding salt to the mixed solution P2 in an amount equal to the content ratio of the salt to the plate-like compound in the composition.

[0210] That is, when the composition contains a plate-like compound and a salt, the mixed liquid P2 contains 10 parts by mass of the plate-like compound, 90 parts by mass of water, and a predetermined amount of salt (parts by mass) in the same content ratio as the salt content to the plate-like compound in the composition (salt content by mass / plate-like compound content by mass). More specifically, when the salt content to the plate-like compound in the composition (salt content by mass / plate-like compound content by mass) is 1 / 10, the mixed liquid P2 contains 10 parts by mass of the plate-like compound, 90 parts by mass of water, and 1 part by mass of salt.

[0211] In addition, the same type of plate-like compound as that in the composition was used as the type of plate-like compound contained in the mixed liquid P1 and the mixed liquid P2.

[0212] The salt contained in the mixed solution P2 is the same as the salt in the composition.

[0213] From the viewpoint of further improving the effects of the present invention, the wavelength dispersion D of the optically anisotropic film P is P It is preferably 1.20 to 1.30.

[0214] Formula (P) wavelength dispersion D P =Re(450) P / Re(550) P

[0215] Re(450) P Re(550) represents the in-plane retardation of the optically anisotropic film P at a wavelength of 450 nm. PIt shows the in-plane retardation of the optically anisotropic film P at a wavelength of 550 nm.

[0216] As mentioned above, the wavelength dispersion D P The relationship of the in-plane retardation of the optically anisotropic film P formed using the plate-like compound is shown.

[0217] Furthermore, Nz represented by formula (N1) of the plate-like compound P1 Among them, from the viewpoint of the better effect of the present invention, Nz P1 It is preferably -0.45 to -0.10, more preferably -0.30 to -0.15, and still more preferably -0.25 to -0.19.

[0218] As described later, Nz P1 These are optical properties of the optically anisotropic film of the plate-like compound, and correspond to the optical properties exhibited by the plate-like compound in the optically anisotropic film.

[0219] Formula (N1)Nz P1 =(nx P1 -nz P1 ) / (nx P1 -ny P1 )

[0220] About nx P , represents the refractive index in the slow axis direction of the in-plane of an optically anisotropic film P1 formed using a mixed solution P3 when the composition does not contain salt, and using a mixed solution P4 when the composition contains salt. The mixed solution P3 is obtained by mixing a non-coloring plate-like compound with water and exhibits lyotropic liquid crystallinity at 20°C. The mixed solution P4 is obtained by mixing a non-coloring plate-like compound, water, and a salt in an amount equal to the content ratio of the salt to the plate-like compound in the composition and exhibits lyotropic liquid crystallinity at 20°C. P1 Represents the refractive index in the fast axis direction of the optically anisotropic film P1. P1 nx represents the refractive index in the thickness direction of the optically anisotropic film P1. P1 、ny P1 and nz P1 are the refractive indices at a wavelength of 550 nm.

[0221] That is, the optically anisotropic film P1 is formed using a mixed solution P3 obtained by mixing a plate-like compound and water and exhibiting lyotropic liquid crystal properties at 20°C when the composition does not contain salt. If the composition contains salt, the optically anisotropic film P1 is formed using a mixed solution P4 obtained by mixing a plate-like compound, water, and a salt in an amount equal to the content ratio of the salt to the plate-like compound in the composition and exhibiting lyotropic liquid crystal properties at 20°C.

[0222] The optically anisotropic film P1 was prepared by coating the mixed solution P1 or mixed solution P2 on a glass substrate using a No. 4 wire rod (moving speed: 100 cm / s) and then drying the mixture naturally at room temperature (20°C) to produce an optically anisotropic film P1 (film thickness of approximately 240 nm).

[0223] As described above, when the composition contains salt, the mixed solution P4 also contains a predetermined amount of salt. Specifically, the same amount of salt as the content ratio of the salt to the plate-like compound in the composition is added to the mixed solution P4 to produce the optically anisotropic film P1.

[0224] That is, when the composition contains a plate-like compound and a salt, the mixed liquid P4 contains the plate-like compound, water, and a predetermined amount of salt (parts by mass) in the same content ratio as the salt content to the plate-like compound in the composition (salt content by mass / plate-like compound content by mass). More specifically, when the salt content to the plate-like compound in the composition (salt content by mass / plate-like compound content by mass) is 1 / 10 and the amount of the plate-like compound in the mixed liquid P4 is 10 parts by mass, the mixed liquid P4 contains 1 part by mass of salt.

[0225] In addition, the same type of plate-like compound as that in the composition was used as the type of plate-like compound contained in the mixed liquid P3 and the mixed liquid P4.

[0226] The salt contained in the mixed solution P2 is the same as the salt in the composition.

[0227] In the mixed liquid P3, the mixing ratio of the plate-like compound and water is not particularly limited as long as the mixed liquid P3 exhibits lyotropic liquid crystallinity at 20° C. Even when the mixing ratio is changed, the optical properties (nx P1 、ny P1 and nz P1 ) also remains unchanged.

[0228] Furthermore, in the mixed solution P4, the mixing ratio of the plate-like compound and water is not particularly limited as long as the mixed solution exhibits lyotropic liquid crystallinity at 20° C. Even when the mixing ratio is changed, the optical properties (nxP1 、ny P1 and nz P1 ) also remains unchanged.

[0229] From the viewpoint of achieving more excellent effects of the present invention, the plate-like compound preferably has a hydrophilic group.

[0230] The hydrophilic group is as defined above.

[0231] The plate-like compound may have only one hydrophilic group or may have multiple hydrophilic groups. When the plate-like compound has multiple hydrophilic groups, the number of the hydrophilic groups is preferably 2 to 4, more preferably 2.

[0232] From the viewpoint of achieving more excellent effects of the present invention, the plate-like compound is preferably a compound represented by formula (Y).

[0233] Formula(Y)R y2 -L y3 -L y1 -R y1 -L y2 -L y4 -R y3

[0234] R y1 represents a divalent monocyclic group or a divalent condensed polycyclic group.

[0235] Examples of the ring contained in the divalent monocyclic group include a monocyclic hydrocarbon ring and a monocyclic heterocyclic ring. The monocyclic hydrocarbon ring may be a monocyclic aromatic hydrocarbon ring or a monocyclic non-aromatic hydrocarbon ring. The monocyclic heterocyclic ring may be a monocyclic aromatic heterocyclic ring or a monocyclic non-aromatic heterocyclic ring.

[0236] As the divalent monocyclic group, a divalent monocyclic aromatic hydrocarbon ring group or a divalent monocyclic aromatic heterocyclic group is preferred from the viewpoint of achieving more excellent effects of the present invention.

[0237] The number of ring structures contained in the divalent fused polycyclic group is not particularly limited, but is preferably 3 to 10, more preferably 3 to 6, and even more preferably 3 to 4 from the viewpoint of achieving more excellent effects of the present invention.

[0238] Examples of the ring contained in the divalent fused polycyclic group include hydrocarbon rings and heterocyclic rings. The hydrocarbon ring may be an aromatic hydrocarbon ring or a non-aromatic hydrocarbon ring. The heterocyclic ring may be an aromatic heterocyclic ring or a non-aromatic heterocyclic ring.

[0239] From the viewpoint of achieving a more excellent effect of the present invention, the divalent fused polycyclic group is preferably composed of an aromatic hydrocarbon ring and a heterocyclic ring. The divalent fused polycyclic group is preferably a conjugated linking group. That is, it is preferably a conjugated divalent fused polycyclic group.

[0240] Examples of the ring constituting the divalent fused polycyclic group include dibenzothiophene-S,S-dioxide (a ring represented by the formula (Y2)), dinaphtho[2,3-b:2',3'-d]furan (a ring represented by the formula (Y3)), 12H-benzo"b"phenoxazine (a ring represented by the formula (Y4)), dibenzo[b,i]dibenzo-p-dioxin (oxanthrene) (a ring represented by the formula (Y5)), benzo[b]naphtho[2',3':5,6]dioxo[2,3-i]dibenzo-p-dioxin (a ring represented by the formula (Y6)), acenaphtho[1,2-b]benzo[g]quinoxaline (a ring represented by the formula (Y7)), 9H-acenaphtho[1,2-b]imidazole[4,5-g]quinoxaline (a ring represented by the formula (Y8)), dibenzo[b,i]dibenzo-p-dioxin (oxanthrene) (a ring represented by the formula (Y9)), (Chrysene)-7,14-dione (ring represented by formula (Y9)) and acetylquinoxaline (ring represented by formula (Y10)).

[0241] That is, examples of the divalent fused polycyclic group include divalent groups formed by removing two hydrogen atoms from the rings represented by formulae (Y2) to (Y10).

[0242] [Chemical Formula 9]

[0243]

[0244] [Chemical Formula 10]

[0245]

[0246] The divalent monocyclic group and the divalent condensed polycyclic group may have a substituent. The type of the substituent is not particularly limited, and for example, the substituent may be substituted with R x1 The groups exemplified as the substituents other than the substituent containing a hydrophilic group possessed by the divalent aromatic ring group having a substituent containing a hydrophilic group and the divalent non-aromatic ring group having a substituent containing a hydrophilic group.

[0247] R y2 and R y3 Each independently represents a hydrogen atom or a hydrophilic group, R y2 and R y3 At least one of represents a hydrophilic group. y2 and R y3 Both preferably represent hydrophilic groups.

[0248] By R y2 and R y3 The hydrophilic group represented by is defined as above.

[0249] L y1 Ly 2Each independently represents a single bond, a divalent aromatic ring group or a group represented by formula (Y1). y1 When it is a divalent monocyclic group, L y1 and L y2 Both represent a divalent aromatic ring group or a group represented by formula (Y1): In formula (Y1), * represents a bonding position.

[0250] Formula (Y1)*-R y4 -(R y5 ) n -*

[0251] R y4 and R y5 Each independently represents a divalent aromatic ring group.

[0252] n represents 1 or 2.

[0253] Composed of L y1 and L y2 The aromatic ring of the divalent aromatic ring group represented by may be a monocyclic structure or a polycyclic structure.

[0254] As the aromatic ring constituting the above-mentioned divalent aromatic ring group, for example, an aromatic hydrocarbon ring or an aromatic heterocyclic ring can be mentioned. y1 and L y2 Examples of the divalent aromatic ring group represented by include divalent aromatic hydrocarbon ring groups and divalent aromatic heterocyclic groups.

[0255] Examples of the aromatic hydrocarbon ring include a benzene ring and a naphthalene ring.

[0256] Examples of the divalent aromatic hydrocarbon group include the following groups: * represents a bonding position.

[0257] [Chemical Formula 11]

[0258]

[0259] Examples of the aromatic heterocyclic ring include a pyridine ring, a thiophene ring, a pyrimidine ring, a thiazole ring, a furan ring, a pyrrole ring, an imidazole ring, and an indole ring.

[0260] Examples of the divalent aromatic heterocyclic group include the following groups: * represents a bonding position.

[0261] [Chemical Formula 12]

[0262]

[0263] By R y4 and R y5 The definition of the divalent aromatic ring group represented by L is also the same as that represented by y1 and L y2The divalent aromatic ring groups represented are the same.

[0264] L y3 and L y4 Each independently represents a single bond, -O-, -S-, an alkylene group, an alkenylene group, an alkynylene group, or a group formed by combining them.

[0265] Examples of the group formed by combining these groups include -O-alkylene and -S-alkylene.

[0266] The number of carbon atoms in the alkylene group is not particularly limited, but is preferably 1 to 3, more preferably 1, from the viewpoint of further improving the effects of the present invention.

[0267] The number of carbon atoms in the alkenylene group and the alkynylene group is not particularly limited, but is preferably 2 to 5, more preferably 2 to 4, from the viewpoint of further improving the effects of the present invention.

[0268] <Other ingredients>

[0269] The composition may contain other components in addition to the rod-like compound and the plate-like compound.

[0270] The composition may also contain a salt (a salt composed of a cation and an anion). As described above, when the plate-like compound has an acid group or a salt thereof, if the composition contains a salt, the planes in the plate-like compound are more likely to associate with each other, thereby easily forming a columnar association.

[0271] The salt is not particularly limited and can be an inorganic salt or an organic salt. From the viewpoint of being more excellent in the effect of the present invention, an inorganic salt is preferred. As the inorganic salt, for example, alkali metal salts, alkaline earth metal salts and transition metal salts can be enumerated. From the viewpoint of being more excellent in the effect of the present invention, an alkali metal salt is preferred.

[0272] The alkali metal salt refers to a salt whose cation is an alkali metal ion. As the alkali metal ion, lithium ion or sodium ion is preferred, and lithium ion is more preferred. That is, as the salt, lithium salt or sodium salt is preferred, and lithium salt is more preferred.

[0273] Examples of the alkali metal salt include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate; and alkali metal hydrogen carbonates such as lithium hydrogen carbonate, sodium hydrogen carbonate, and potassium hydrogen carbonate.

[0274] In addition to the above, examples of the alkali metal salt include phosphates and chlorides.

[0275] Examples of the anions of the salts include hydroxide ions, carbonate ions, chloride ions, sulfate ions, nitrate ions, phosphate ions, borate ions, tetrafluoroborate ions, hexafluorophosphate ions, perchlorate ions, toluenesulfonate ions, oxalate ions, formate ions, trifluoroacetate ions, trifluoromethanesulfonate ions, hexafluorophosphate ions, bis(fluoromethanesulfonyl)imide ions, bis(pentafluoroethanesulfonyl)imide ions, and bis(trifluoromethanesulfonyl)imide ions.

[0276] When the plate-like compound has a salt of an acid group, the cation in the salt of the acid group and the cation in the salt used above are preferably of the same type.

[0277] The composition may also contain a solvent. Examples of the solvent include polar solvents such as water, alcohol, and dimethylformamide, and non-polar solvents such as hexane. Among them, polar solvents are preferred, and water and alcohol are more preferred.

[0278] Examples of additives that may be contained in the composition include, in addition to the above, polymerizable compounds, polymerization initiators, wavelength dispersion controllers, optical property adjusters, surfactants, adhesion improvers, lubricants, alignment control agents, and ultraviolet absorbers.

[0279] <Composition>

[0280] The composition contains at least a rod-like compound and a plate-like compound.

[0281] The composition corresponds to a lyotropic liquid crystal composition.

[0282] Here, a lyotropic liquid crystal composition refers to a composition that exhibits a phase transition from an isotropic phase to a liquid crystal phase in a solution state by changing temperature and concentration. Specifically, the composition is a composition that exhibits lyotropic liquid crystal properties in a solution state containing various components, such as a rod-shaped compound, a plate-shaped compound, and a solvent, by adjusting the concentrations of each compound. Furthermore, even if a composition contains an excess of solvent and does not exhibit lyotropic liquid crystal properties in this state, if it exhibits lyotropic liquid crystal properties when the concentration is changed, such as during the drying process after application, the composition is considered to be a lyotropic liquid crystal composition.

[0283] The content of the rod-shaped compound and the plate-shaped compound in the composition is not particularly limited, but is preferably 60 to 100% by mass, more preferably 80 to 99% by mass, based on the total solid content in the composition.

[0284] The total solid content refers to the components that can form an optically anisotropic film excluding the solvent. In addition, even if the properties of the above components are liquid, they are also calculated as solid content.

[0285] The composition may contain only one type of rod-shaped compound, or may contain two or more types of rod-shaped compounds.

[0286] The composition may contain only one plate-like compound, or may contain two or more plate-like compounds.

[0287] The content of the rod-shaped compound relative to the total mass of the rod-shaped compound and the plate-shaped compound in the composition is not particularly limited, but from the perspective of achieving excellent effects of the present invention, it is preferably greater than 50% by mass, more preferably 55% by mass or greater. The upper limit is not particularly limited, but is preferably 90% by mass or less, more preferably 80% by mass.

[0288] When the composition contains a salt, the salt content is not particularly limited. However, from the viewpoint of further improving the effects of the present invention, the ratio W obtained from formula (W) is preferably 0.25 to 1.75, more preferably 0.50 to 1.50, and even more preferably 0.75 to 1.15.

[0289] [Formula 1]

[0290]

[0291] In formula (W), C1 represents the molar amount of cations contained in the salt of the acid group possessed by the rod-shaped compound. If the rod-shaped compound does not have a salt of an acid group, C1 is 0.

[0292] C2 represents the molar amount of cations contained in the salt of the acid group possessed by the plate-like compound. If the plate-like compound does not have a salt of the acid group, C2 is 0.

[0293] C3 represents the molar amount of cations contained in the salt.

[0294] A1 represents the total molar amount of acid groups or their salts contained in the rod-shaped compound. When the rod-shaped compound contains both acid groups and their salts, the total molar amount represents the sum of the molar amounts of the acid groups and their salts. When the rod-shaped compound contains only one of the acid groups and their salts, the molar amount of the absent one is 0.

[0295] A2 represents the total molar amount of acid groups or their salts contained in the plate-like compound. When the plate-like compound contains both acid groups and their salts, the total molar amount represents the sum of the molar amounts of the acid groups and their salts. When the plate-like compound contains only one of the acid groups and their salts, the molar amount of the absent acid group is 0.

[0296] For example, in a composition containing a rod-shaped compound having a SO3Li group, a plate-shaped compound having a SO3Li group, and LiOH, when the molar amount of the SO3Li group of the rod-shaped compound is 5 mmol, the molar amount of the SO3Li group of the plate-shaped compound is 8 mmol, and the molar amount of LiOH is 8 mmol, the molar amount of the cation contained in the salt of the acid group of the rod-shaped compound is calculated to be 5 mmol, the molar amount of the cation contained in the salt of the acid group of the plate-shaped compound is calculated to be 8 mmol, and the molar amount of the cation contained in the LiOH is calculated to be 8 mmol, and the ratio W is calculated to be {(5+8+8)-(5+8)} / 8=1.

[0297] Assuming that the rod-shaped compound is a rod-shaped compound having SO 3 H groups, and the molar amount of SO 3 H groups in the rod-shaped compound is 5 mmol, the ratio W is calculated to be {(8+8)-(5+8)} / 8=0.375.

[0298] The ratio W represents the amount of cations from the excess salt in the composition relative to the acid groups or salts thereof in the plate-like compound. Specifically, the ratio W represents the ratio of the acid groups and excess cations not forming salts in the rod-shaped and plate-like compounds relative to the acid groups or salts thereof in the plate-like compound. When the composition contains a predetermined amount of cations relative to the acid groups or salts thereof in the plate-like compound, the plate-like compound readily acquires a predetermined structure in the optically anisotropic film, facilitating the production of a desired optically anisotropic film.

[0299] When the composition contains a salt, the mass ratio of the salt content to the plate-like compound content in the composition is not particularly limited, but is preferably 0.010 to 0.300, more preferably 0.010 to 0.200, and even more preferably 0.025 to 0.150.

[0300] As mentioned above, the composition may also contain a solvent.

[0301] The solid content concentration of the composition is not particularly limited, but is preferably 1 to 50% by mass, more preferably 3 to 30% by mass, based on the total mass of the composition, from the viewpoint of achieving excellent effects of the present invention.

[0302] As described above, the composition is a lyotropic liquid crystal composition. Therefore, the composition may be in a state where it contains a predetermined amount of solvent and exhibits lyotropic liquid crystal properties (a state where it exhibits lyotropic liquid crystal properties), or may be a composition where it contains an excess amount of solvent and does not exhibit lyotropic liquid crystal properties in this state (exhibiting an isotropic phase), or may be a composition where the solvent evaporates during formation of an optically anisotropic film and exhibits lyotropic liquid crystal properties during film formation.

[0303] Furthermore, as described later, when an alignment film is disposed on a support, lyotropic liquid crystal properties are expressed during the drying process after the composition is applied, thereby inducing alignment of the compound and forming an optically anisotropic film.

[0304] <Method for Manufacturing Optically Anisotropic Film>

[0305] The method for producing the optically anisotropic film of the present invention is not particularly limited as long as the above-mentioned composition is used. For example, a method of forming an optically anisotropic film by coating the composition and orienting the rod-shaped compounds and plate-shaped compounds in the coating is preferred.

[0306] The steps of the above method are described in detail below.

[0307] First, the composition is applied. Usually, the composition is applied on a support.

[0308] The support used is a member having the function of serving as a base material for coating the composition. The support may also be a so-called pseudo support.

[0309] As the support (pseudo-support), a plastic substrate or a glass substrate can be cited. As the material constituting the plastic substrate, polyester resins such as polyethylene terephthalate, polycarbonate resins, (meth)acrylic resins, epoxy resins, polyurethane resins, polyamide resins, polyolefin resins, cellulose resins, silicone resins, and polyvinyl alcohol can be cited.

[0310] The thickness of the support may be approximately 5 to 1000 μm, preferably 10 to 250 μm, and more preferably 15 to 90 μm.

[0311] Furthermore, an alignment film may be disposed on the support as needed.

[0312] Alignment films generally have polymers as their main components. Polymers for alignment films are described in numerous documents, and many commercial products are available. Polymers for alignment films are preferably polyvinyl alcohol, polyimide, or their derivatives.

[0313] In addition, it is preferable to subject the alignment film to a known rubbing treatment.

[0314] Furthermore, a photo-alignment film may be used as the alignment film.

[0315] The thickness of the alignment film is preferably 0.01 to 10 μm, more preferably 0.01 to 1 μm.

[0316] Examples of the coating method include well-known methods, such as curtain coating, extrusion coating, roll coating, dip coating, spin coating, print coating, spray coating, and slide coating.

[0317] Furthermore, if a coating method with shearing is employed, two processes, namely, alignment of the compound and coating, can be performed simultaneously.

[0318] Furthermore, continuous coating can be used to continuously orient rod-shaped and plate-shaped compounds simultaneously. Examples of continuous coating methods include curtain coating, extrusion coating, roll coating, and slide coating. Specifically, a die coater, knife coater, or rod coater is preferably used as the coating apparatus.

[0319] As a method for orienting the rod-shaped compound and the plate-shaped compound in the coating film, a method of applying shearing is mentioned as described above.

[0320] The coating film formed on the support may be subjected to a heat treatment as needed.

[0321] The conditions for heating the coating film are not particularly limited, but the heating temperature is preferably 50 to 250° C., and the heating time is preferably 10 seconds to 10 minutes.

[0322] Furthermore, after heating the coating film, the coating film may be cooled as needed. The cooling temperature is preferably 20 to 200°C, more preferably 20 to 150°C.

[0323] As another method for orienting the rod-shaped compound and the plate-shaped compound in the coating film, there is mentioned a method of using an orientation film as described above.

[0324] The orientation direction can be controlled by pre-treatment of the orientation film in a predetermined direction. In particular, when continuous coating is performed using a roll-shaped support, it is preferable to use an orientation film when the orientation is oblique to the conveying direction.

[0325] In the method of using an alignment film, the concentration of the solvent in the composition used is not particularly limited and may be a concentration at which the composition exhibits lyotropic liquid crystal properties, or a concentration lower than that. As described above, since the composition is a lyotropic liquid crystal composition, even when the solvent concentration in the composition is high (when the composition itself exhibits an isotropic phase), the lyotropic liquid crystal properties exhibited during the drying process after application of the composition can induce alignment of the compound on the alignment film, thereby forming an optically anisotropic film.

[0326] Furthermore, after forming the optically anisotropic film, a treatment for fixing the orientation state of the rod-like compound and the plate-like compound may be performed as needed.

[0327] The method for fixing the orientation state of the rod-shaped compound and the plate-shaped compound is not particularly limited, and as described above, an example includes a method of heating the coating film and then cooling it.

[0328] Furthermore, when at least one of the rod-shaped compound and the plate-shaped compound has an acid group or its salt, a method for fixing the orientation of the rod-shaped compound and the plate-shaped compound can include contacting a solution containing polyvalent metal ions with the formed coating film. When the solution containing polyvalent metal ions is brought into contact with the formed coating film, the polyvalent metal ions are supplied to the coating film. The polyvalent metal ions supplied to the coating film serve as crosslinking points between the acid groups or their salts possessed by the rod-shaped compound and / or the plate-shaped compound, forming a crosslinked structure in the coating film, thereby fixing the orientation of the rod-shaped compound and the plate-shaped compound.

[0329] The type of polyvalent metal ion used is not particularly limited, but from the viewpoint of easily fixing the orientation state of the rod-like compound and the plate-like compound, alkaline earth metal ions are preferred, and calcium ions are more preferred.

[0330] <Characteristics of Optically Anisotropic Film>

[0331] When measuring the ultraviolet-visible absorption spectrum by irradiating linearly polarized light from the normal direction of the optically anisotropic film while changing the orientation of the linearly polarized light, the direction in which the absorbance of the rod-shaped compound at the maximum absorption wavelength in the wavelength range of 230 to 400 nm is the highest is defined as the first direction, and the direction in which the absorbance of the plate-shaped compound at the maximum absorption wavelength in the wavelength range of 230 to 400 nm is the highest is defined as the second direction, and the first direction and the second direction are orthogonal to each other.

[0332] As the above-mentioned measurement method, for example, Figure 5 As shown, a method can be mentioned in which the orientation of the linearly polarized light is changed while performing the following measurement. This measurement is performed by irradiating the optically anisotropic film 20 with linearly polarized light indicated by a straight solid line to obtain an ultraviolet-visible absorption spectrum, and then changing the orientation of the linearly polarized light (changing the orientation of the linearly polarized light counterclockwise) to irradiate the optically anisotropic film 20 with linearly polarized light indicated by a straight dotted line to obtain an ultraviolet-visible absorption spectrum.

[0333] As mentioned above, the above characteristics show Figure 1 The arrangement of the rod-shaped compound and the plate-shaped compound is shown. Figure 1 In the figure, the direction of the maximum absorbance of the rod-shaped compound at the maximum absorption wavelength in the range of 230 to 400 nm corresponds to the x-axis direction, and the direction of the maximum absorbance of the plate-shaped compound at the maximum absorption wavelength in the range of 230 to 400 nm corresponds to the y-axis direction.

[0334] As described above, the term "orthogonal" means being within the range of 90±5° (85 to 95°), preferably within the range of 90±3° (87 to 93°).

[0335] The measurement method for the first direction and the second direction is not particularly limited, and a known method can be used.

[0336] As described above, the first and second directions are obtained by measuring the UV-visible absorption spectrum by irradiating the optically anisotropic film with linearly polarized light from the normal direction while changing the orientation of the linearly polarized light (the orientation of the polarization axis of the linearly polarized light). As a method for changing the orientation of the linearly polarized light, a method of rotating the optically anisotropic film can be cited.

[0337] The Nz coefficient of the optically anisotropic film satisfies the relationship of formula (1).

[0338] Formula (1) 0.40≤Nz coefficient≤0.60

[0339] Among them, 0.42 to 0.58 is preferred, and 0.45 to 0.54 is more preferred.

[0340] An optically anisotropic film exhibits reverse wavelength dispersion. Reverse wavelength dispersion refers to the fact that, when in-plane retardation (Re) values ​​are measured in at least a portion of the visible light wavelength range, the Re values ​​remain constant or increase as the measured wavelength increases. In the present invention, an optically anisotropic film exhibits reverse wavelength dispersion only if it satisfies the following equations (2) and (3).

[0341] Formula (2)Re(450) / Re(550)<1.00

[0342] Re(450) represents the in-plane retardation of the optically anisotropic film at a wavelength of 450 nm, and Re(550) represents the in-plane retardation of the optically anisotropic film at a wavelength of 550 nm.

[0343] Among them, Re(450) / Re(550) is preferably 0.87 or less, more preferably 0.85 or less. Furthermore, Re(450) / Re(550) is preferably 0.60 or more, preferably 0.72 or more, more preferably 0.82 or more.

[0344] Formula (3)Re(650) / Re(550)>1.00

[0345] Re(650) represents the in-plane retardation of the optically anisotropic film at a wavelength of 650 nm.

[0346] Among them, Re(650) / Re(550) is preferably 1.02 or more, more preferably 1.05 or more. The upper limit is not particularly limited, but is preferably 1.25 or less, more preferably 1.20 or less.

[0347] Re(550) of the optically anisotropic film is not particularly limited, but is preferably 110 to 160 nm, more preferably 120 to 150 nm, from the viewpoint of being useful as a λ / 4 plate.

[0348] The Rth(550) of the optically anisotropic film is not particularly limited, but is preferably -50 to 40 nm, more preferably -40 to 30 nm.

[0349] The degree of orientation of the rod-shaped compound in the optically anisotropic film is preferably 0.60 or more, and the degree of orientation of the plate-shaped compound in the optically anisotropic film is preferably 0.60 or more.

[0350] The degree of orientation of the rod-shaped compound and the upper limit of the degree of orientation of the rod-shaped compound are not particularly limited, and 1.00 is an example.

[0351] The rod-shaped compound orientation degree indicates the degree of orientation of the rod-shaped compound in the optically anisotropic film. As shown in the formula below, 1.0 is the upper limit. The closer the rod-shaped compound orientation degree is to 1.0, the more the molecular axes of the rod-shaped compound (the direction in which the rod-shaped compound extends) are aligned in one direction.

[0352] The orientation degree of the plate-like compound indicates the degree of orientation of the plate-like compound in the optically anisotropic film, and as shown in the formula below, 1.0 is the upper limit. The closer the orientation degree of the plate-like compound is to 1.0, the more the major axis of the plate-like compound is aligned in one direction.

[0353] The orientation degree of the rod-shaped compound and the orientation degree of the plate-shaped compound can be calculated by the following formula using the absorbance Ax in the direction of maximum absorption from each compound (hereinafter also referred to as the "first direction") and the absorbance Ay in the direction orthogonal to the first direction (hereinafter also referred to as the "second direction").

[0354] Orientation degree = [(Ax / Ay)-1] / [(Ax / Ay)+2]

[0355] For example, when calculating the orientation degree of the plate-like compound, the absorbance Ax in the direction where the absorption from the plate-like compound is maximum in the in-plane direction of the optically anisotropic film is calculated. P And the absorbance Ay in the direction perpendicular to the above direction P , substitute each value into the above formula to calculate the orientation degree of the plate-like compound.

[0356] As the absorption from each of the above compounds, it is preferred to use the absorption at the longest wavelength of the maximum absorption wavelength of each compound within the wavelength range of 230 to 400 nm. For example, if the absorption at the longest wavelength of the maximum absorption wavelength of the plate-like compound within the wavelength range of 230 to 400 nm is 345 nm, the direction of maximum absorption at 345 nm is the first direction, and the second direction corresponds to a direction orthogonal to the first direction.

[0357] Furthermore, as described later, the maximum absorption wavelength of the rod-shaped compound is preferably shorter than that of the plate-shaped compound. In this case, when measuring the absorbance at the maximum absorption wavelength of the rod-shaped compound in the optically anisotropic film, the resulting absorbance includes a portion of absorption due to the plate-shaped compound. To measure the absorbance at the maximum absorption wavelength of the rod-shaped compound, the absorbance due to absorption due to the plate-shaped compound can be determined by subtracting the absorbance due to absorption due to the plate-shaped compound from the measured absorbance. The absorbance due to absorption due to the plate-shaped compound can be calculated from the absorption coefficient of the plate-shaped compound at its wavelength and its concentration in the optically anisotropic film.

[0358] In addition, the measurement method in the first direction and the second direction is not particularly limited, and a known method can be used.

[0359] For example, there is a method of measuring an ultraviolet-visible absorption spectrum by irradiating the optically anisotropic film with linearly polarized light from the normal direction while changing the orientation of the linearly polarized light (or the orientation of the polarization axis of the linearly polarized light).

[0360] Furthermore, from the viewpoint of achieving more excellent effects of the present invention, preferred embodiments of the optically anisotropic film include Embodiments 1 to 7 shown in Table 1.

[0361] In Embodiments 1 to 7, Nz of the rod-shaped compound in each optically anisotropic film is represented. R , rod-shaped compound D R , orientation degree of rod-shaped compounds, Nz of plate-shaped compounds P , D of plate-like compounds P , the orientation degree of the plate-like compound, and the content ratio (mass %) of the plate-like compound relative to the total amount of the plate-like compound and the rod-like compound. For example, in the optically anisotropic film shown in embodiment 1, the Nz of the rod-like compound is R is 0.98~1.02, and the D P is 1.08 to 1.12 (preferably 1.09 to 1.11), the orientation degree of the rod-shaped compound is 0.65 to 0.72, and the Nz of the plate-shaped compound is P is -0.25 to -0.15 (preferably -0.25 to -0.19), and the D PThe relative mass of the plate-like compound is 1.20 to 1.24, the orientation degree of the plate-like compound is 0.65 to 0.72, and the content ratio of the plate-like compound to the total amount of the plate-like compound and the rod-like compound is 41 to 44% by mass.

[0362] [Table 1]

[0363]

[0364] The thickness of the optically anisotropic film is not particularly limited, but is preferably 10 μm or less, more preferably 0.5 to 8.0 μm, and even more preferably 0.5 to 6.0 μm from the viewpoint of thinning.

[0365] In this specification, the thickness of an optically anisotropic film refers to the average thickness of the optically anisotropic film. The average thickness is obtained by measuring the thickness of at least five arbitrary locations of the optically anisotropic film and taking the arithmetic average of the thicknesses.

[0366] <Purpose>

[0367] The optically anisotropic film can be used in various applications. For example, the in-plane retardation of the optically anisotropic film can be adjusted to use the film as a so-called λ / 4 plate or λ / 2 plate.

[0368] A λ / 4 plate is a plate that converts linearly polarized light of a specific wavelength into circularly polarized light (or vice versa). More specifically, it is a plate whose in-plane retardation Re at a predetermined wavelength of λ nm is λ / 4 (or an odd multiple thereof).

[0369] The in-plane retardation (Re(550)) of the λ / 4 plate at a wavelength of 550nm can have an error of about 25nm centered around the ideal value (137.5nm), for example, preferably 110 to 160nm, more preferably 120 to 150nm.

[0370] Furthermore, a λ / 2 plate refers to an optically anisotropic film whose in-plane retardation Re(λ) at a specific wavelength λ nm satisfies Re(λ) ≈ λ / 2. This equation can be achieved at any wavelength in the visible light region (e.g., 550 nm). The in-plane retardation Re(550) at a wavelength of 550 nm preferably satisfies the following relationship:

[0371] 210nm≤Re(550)≤300nm

[0372] <Optical Film>

[0373] The optically anisotropic film may be combined with other layers to be used as an optical film. That is, the optical film of the present invention includes the above-mentioned optically anisotropic film and other layers.

[0374] Examples of other layers include the above-mentioned alignment film and support.

[0375] The arrangement position of the optically anisotropic film in the optical film is not particularly limited, and for example, a form including a support, an alignment film, and an optically anisotropic film in this order can be mentioned.

[0376] <Polarizing Plate>

[0377] The optically anisotropic film of the present invention can be preferably used in a polarizing plate.

[0378] That is, the polarizing plate (preferably a circular polarizing plate) of the present invention includes an optically anisotropic film or an optical film and a polarizer. In addition, a circular polarizing plate refers to an optical element that converts unpolarized light into circularly polarized light.

[0379] The polarizer may be any one having a function of converting light into specific linearly polarized light (linear polarizer), and mainly an absorption-type polarizer can be used.

[0380] Examples of absorption-type polarizers include iodine-based polarizers, dye-based polarizers using dichroic dyes, and polyene-based polarizers. Iodine-based and dye-based polarizers include coated polarizers and stretched polarizers, both of which can be used. However, polarizers made by adsorbing iodine or a dichroic dye onto polyvinyl alcohol and then stretching it are preferred.

[0381] The relationship between the slow axis of the optically anisotropic film and the absorption axis of the polarizer is not particularly limited. However, when the optically anisotropic film is a λ / 4 plate and the optical film is used as a circularly polarizing film, the angle formed by the in-plane slow axis of the optically anisotropic film and the absorption axis of the polarizer is preferably in the range of 45±10°. In other words, the angle formed by the in-plane slow axis of the optically anisotropic film and the absorption axis of the polarizer is preferably in the range of 35 to 55°.

[0382] <Display device>

[0383] The circularly polarizing plate of the present invention can be preferably used in a display device. That is, the circularly polarizing plate of the present invention can be suitably used as a so-called antireflection film.

[0384] The display device of the present invention includes a display element and the circular polarizing plate described above. The circular polarizing plate is disposed on the viewing side, and the polarizer is disposed on the viewing side of the circular polarizing plate.

[0385] The display device is not particularly limited, and examples thereof include organic EL display elements and liquid crystal display elements, with organic EL display elements being preferred.

[0386] Example

[0387] The following examples and comparative examples are given to further illustrate the characteristics of the present invention. About the materials, usage amounts, ratios, processing contents and processing steps shown in the following examples, as long as they do not depart from the purpose of the present invention, then appropriate changes can be made. Therefore, the scope of the present invention should not be interpreted in a restrictive manner by the specific examples shown below.

[0388] <Synthesis>

[0389] The following plate-shaped compounds I-1 to I-5 and rod-shaped compounds II-1 to II-4 were synthesized using a known method. Plate-shaped compound I-4 corresponds to a mixture of two compounds, with the mixing ratio of the left-hand compound to the right-hand compound (mass of the left-hand compound / mass of the right-hand compound) being 1 / 1. Furthermore, rod-shaped compounds II-1 to II-4 are high molecular weight compounds (n is 2 or greater). Rod-shaped compound II-1 has a number average molecular weight of 24,000 and a molecular weight distribution of 6.8; rod-shaped compound II-2 has a number average molecular weight of 30,000 and a molecular weight distribution of 5.7; rod-shaped compound II-3 has a number average molecular weight of 25,000 and a molecular weight distribution of 5.1; and rod-shaped compound II-4 has a number average molecular weight of 16,000 and a molecular weight distribution of 5.6.

[0390] In addition, the plate-like compounds I-1 to I-5 and the rod-like compounds II-1 to II-4 all exhibited lyotropic liquid crystal properties.

[0391] Furthermore, plate-shaped compounds I-1 to I-5 and rod-shaped compounds II-1 to II-4 all met the aforementioned non-coloring requirement. More specifically, when measuring the UV-visible absorption spectra of solutions obtained by dissolving each of these compounds at a concentration such that the absorbance at the maximum absorption wavelength in the ultraviolet region (230 to 400 nm) was 1.0, the absorbance within the visible light region (wavelength 400 to 700 nm) was 0.1 or less.

[0392] [Chemical Formula 13]

[0393]

[0394] [Chemical Formula 13]

[0395]

[0396] [Chemical Formula 14]

[0397]

[0398] [Chemical Formula 13]

[0399]

[0400] The plate-like compound I-1 has a maximum absorption wavelength at 345 nm within the wavelength range of 230 to 400 nm.

[0401] The plate-like compound I-2 has a maximum absorption wavelength at 350 nm within the wavelength range of 230 to 400 nm.

[0402] The plate-like compound I-3 has a maximum absorption wavelength at 345 nm within the wavelength range of 230 to 400 nm.

[0403] The plate-like compound I-4 has a maximum absorption wavelength at 320 nm within the wavelength range of 230 to 400 nm.

[0404] The plate-like compound I-5 has a maximum absorption wavelength at 345 nm within the wavelength range of 230 to 400 nm.

[0405] The rod-shaped compound II-1 has a maximum absorption wavelength at 260 nm within the wavelength range of 230 to 400 nm.

[0406] The rod-shaped compound II-2 has a maximum absorption wavelength at 260 nm within the wavelength range of 230 to 400 nm.

[0407] The rod-shaped compound II-3 has a maximum absorption wavelength at 290 nm within the wavelength range of 230 to 400 nm.

[0408] The rod-shaped compound II-4 has a maximum absorption wavelength at 260 nm within the wavelength range of 230 to 400 nm.

[0409] <Example 1>

[0410] An optically anisotropic film-forming composition 1 having the following composition was prepared. The optically anisotropic film-forming composition 1 is a composition exhibiting lyotropic liquid crystal properties.

[0411]

[0412] The optically anisotropic film-forming composition 1 prepared above was applied to a glass substrate using a wire bar (movement speed: 100 cm / s) and then naturally dried at room temperature (20°C). The resulting coating was then immersed in a 1 mol / L calcium chloride aqueous solution for 5 seconds, rinsed with ion-exchanged water, and air-dried to fix the orientation, thereby producing an optically anisotropic film 1.

[0413] <Examples 2 to 10, Comparative Examples 1 and 2>

[0414] Optically anisotropic films 2 to 10 and C1 to C2 were produced in the same manner as in Example 1 except that the rod-shaped compound or plate-shaped compound was changed to the compound shown in Table 2 below and the amount of lithium hydroxide used was adjusted as shown in Table 2 below.

[0415] In Example 10, cesium hydroxide was used instead of lithium hydroxide.

[0416] In addition, Re(550) of the optically anisotropic films produced in Examples 1 to 10 and Comparative Examples 1 and 2 was 142 nm.

[0417] Furthermore, the above-mentioned ratio W in Example 1 is 0.67, the above-mentioned ratio W in Example 2 is 0.48, the above-mentioned ratio W in Example 3 is 0.61, the above-mentioned ratio W in Example 4 is 0.80, the above-mentioned ratio W in Example 5 is 0.38, the above-mentioned ratio W in Example 6 is 0.96, the above-mentioned ratio W in Example 7 is 0.48, the above-mentioned ratio W in Example 8 is 1.34, and the above-mentioned ratio W in Example 9 is 0.32.

[0418] <Evaluation>

[0419] The in-plane retardation and Nz coefficient of the obtained optically anisotropic films 1 to 10 and optically anisotropic films C1 and C2 were measured at respective wavelengths.

[0420] The results are summarized in Table 2.

[0421] In Table 2, “D R The column "" indicates the wavelength dispersion D represented by formula (R) of the rod-shaped compound. R Wavelength dispersion D R For example, in Example 1, a mixed solution R obtained by mixing rod-shaped compound II-1 (10 parts by mass) and water (90 parts by mass) was used to prepare an optically anisotropic film R by the above method, and the wavelength dispersion D was obtained. R .

[0422] In Table 2, “λ R The column "" indicates the maximum absorption wavelength of the rod-like compound.

[0423] In Table 2, “D P The column "" indicates the wavelength dispersion D represented by the formula (P) of the plate-like compound. P .

[0424] In Table 2, “Nz P " column represents Nz represented by formula (N) of the above plate-like compound. P .

[0425] In Table 2, “NzP1 " column represents Nz represented by formula (N1) of the above plate-like compound. P1 .

[0426] In Table 2, “λ P The column "" indicates the maximum absorption wavelength of the plate-like compound.

[0427] Wavelength dispersion D P and Nz P The measurement method of is as described above. For example, in Example 1, a mixed solution P2 obtained by mixing plate-like compound I-1 (10 parts by mass), water (90 parts by mass) and lithium hydroxide (0.59 parts by mass) was used to prepare an optically anisotropic film P by the above method, and the wavelength dispersion D was obtained. P and Nz P .

[0428] Nz P1 The measurement method of Nz is as described above. For example, in Example 1, the mixed solution P4 obtained by mixing the plate-like compound I-1 (10 parts by mass), water (90 parts by mass) and lithium hydroxide (0.59 parts by mass) exhibited lyotropic liquid crystallinity at 20°C. Therefore, the mixed solution P4 was used to prepare an optically anisotropic film P1 by the above method, and Nz was obtained. P1 . In addition, in any of the mixed liquid P4-1 obtained by mixing the plate-like compound I-1 (5 parts by mass), lithium hydroxide (0.30 parts by mass) and water (95 parts by mass), the mixed liquid P4-2 obtained by mixing the plate-like compound I-1 (15 parts by mass), lithium hydroxide (0.89 parts by mass) and water (85 parts by mass), and the mixed liquid P4-3 obtained by mixing the plate-like compound I-1 (20 parts by mass), lithium hydroxide (1.18 parts by mass) and water (80 parts by mass), lyotropic liquid crystallinity was exhibited at 20°C. Moreover, using these mixed liquids P4-1 to P4-3, respectively, an optically anisotropic film P1 was prepared by the above method and Nz was measured. P1 , all the results are the same as the value (-0.21) obtained by using the mixed solution P4. In other examples, even if the concentration of the plate-like compound is changed, as long as the mixed solution shows lyotropic liquid crystallinity, the obtained Nz P1 The value of is also the same.

[0429] In Table 2, in the column "Relationship between the first direction and the second direction", the case where the first direction and the second direction are orthogonal to each other is designated as "A", and the case where they are not orthogonal to each other is designated as "B".

[0430]

[0431] As shown in Table 2, the optically anisotropic film of the present invention exhibited predetermined effects.

[0432] By comparing Examples 1 to 10, P (or Nz P1 ) is in the range of -0.30 to -0.15 (more preferably in the range of -0.25 to -0.19), the reverse wavelength dispersion is more excellent and the Nz coefficient is closer to a value of 0.50.

[0433] Furthermore, the fact that the reverse wavelength dispersion is more excellent means that the value of Re(450) / Re(550) is closer to 0.82 or the value of Re(650) / Re(550) is closer to 1.18.

[0434] Explanation of symbols

[0435] 10-Support, 12-Rod-shaped compound, 14-Specific compound, 20-Optically anisotropic film.

Claims

1. An optically anisotropic film formed using a lyotropic liquid crystal composition containing a non-coloring rod-shaped compound and a non-coloring plate-shaped compound, wherein: When measuring an ultraviolet-visible absorption spectrum by irradiating the optically anisotropic film with linearly polarized light while changing its orientation, the direction in which the absorbance of the rod-shaped compound at the maximum absorption wavelength within the wavelength range of 230 to 400 nm is the highest is defined as a first direction, and the direction in which the absorbance of the plate-shaped compound at the maximum absorption wavelength within the wavelength range of 230 to 400 nm is the highest is defined as a second direction, the first direction and the second direction being orthogonal to each other. The maximum absorption wavelength of the rod-shaped compound in the wavelength range of 230 to 400 nm is smaller than the maximum absorption wavelength of the plate-shaped compound in the wavelength range of 230 to 400 nm. The plate-like compound represented by formula (N) is Nz P -0.25 to -0.19, Formula (N) Nz P = (nx P - nz P ) / (nx P - ny P ), About nx P , represents the refractive index in the slow axis direction of the plane of the optically anisotropic film P formed by using a mixed solution P1 when the composition does not contain salt, and using a mixed solution P2 when the composition contains salt, wherein the mixed solution P1 is obtained by mixing 10 parts by mass of the non-coloring plate-like compound and 90 parts by mass of water, and the mixed solution P2 is obtained by mixing 10 parts by mass of the non-coloring plate-like compound, 90 parts by mass of water, and an amount of the salt in an amount such that the content ratio of the salt to the plate-like compound in the composition is the same, ny P represents the refractive index in the fast axis direction of the optically anisotropic film P, nz P It represents the refractive index of the optically anisotropic film P in the thickness direction.

2. An optically anisotropic film formed using a lyotropic liquid crystal composition containing a non-coloring rod-shaped compound and a non-coloring plate-shaped compound, wherein: When measuring an ultraviolet-visible absorption spectrum by irradiating the optically anisotropic film with linearly polarized light while changing its orientation, the direction in which the absorbance of the rod-shaped compound at the maximum absorption wavelength within the wavelength range of 230 to 400 nm is the highest is defined as a first direction, and the direction in which the absorbance of the plate-shaped compound at the maximum absorption wavelength within the wavelength range of 230 to 400 nm is the highest is defined as a second direction, the first direction and the second direction being orthogonal to each other. The maximum absorption wavelength of the rod-shaped compound in the wavelength range of 230 to 400 nm is smaller than the maximum absorption wavelength of the plate-shaped compound in the wavelength range of 230 to 400 nm. The plate-like compound represented by formula (N1) is Nz P1 -0.25 to -0.19, Formula (N1) Nz P1 =(nx P1 - nz P1 ) / (nx P1 - ny P1 ), About nx P1 , represents the refractive index in the slow axis direction of the plane of the optically anisotropic film P1 formed by using a mixed solution P3 when the composition does not contain salt, and using a mixed solution P4 when the composition contains salt, wherein the mixed solution P3 is obtained by mixing the non-coloring plate-like compound with water and exhibits lyotropic liquid crystal properties at 20°C, and the mixed solution P4 is obtained by mixing the non-coloring plate-like compound, water, and the salt in an amount having the same content ratio as the content ratio of the salt to the plate-like compound in the composition and exhibits lyotropic liquid crystal properties at 20°C, ny P1 represents the refractive index in the fast axis direction of the optically anisotropic film P1, nz P1 It represents the refractive index in the thickness direction of the optically anisotropic film P1.

3. The optically anisotropic film according to claim 1 or 2, wherein The rod-shaped compound and the plate-shaped compound are both lyotropic liquid crystal compounds.

4. The optically anisotropic film according to claim 1 or 2, wherein The rod-shaped compound and the plate-shaped compound have a hydrophilic group.

5. The optically anisotropic film according to claim 1 or 2, wherein The rod-shaped compound is a polymer having a repeating unit represented by formula (X), R x1 represents a divalent aromatic ring group having a substituent containing a hydrophilic group, a divalent non-aromatic ring group having a substituent containing a hydrophilic group, or a group represented by formula (X1), Formula (X1)*-R x3 -L x3 -R x4 -* In formula (X1), * represents the bonding position, R x3 and R x4 Each independently represents a divalent aromatic ring group which may have a substituent containing a hydrophilic group, or a divalent non-aromatic ring group which may have a substituent containing a hydrophilic group, R x3 and R x4 At least one of them represents a divalent aromatic ring group having a substituent containing a hydrophilic group, or a divalent non-aromatic ring group having a substituent containing a hydrophilic group, L x3 represents a single bond, -O-, -S-, an alkylene group, an alkenylene group or an alkynylene group, R x2 represents a divalent non-aromatic ring group or a group represented by formula (X2), Formula (X2)*-Z x1 -Z x2 -*, Z x1 and Z x2 Each independently represents a divalent non-aromatic ring group, L x1 and L x2 Each independently represents -CONH-, -COO-, -O- or -S-, In formula (X1), * represents the bonding position, In formula (X2), * represents a bonding position.

6. The optically anisotropic film according to claim 1 or 2, wherein The plate-like compound is a compound represented by formula (Y), Formula(Y)R y2 -L y3 -L y1 -R y1 -L y2 -L y4 -R y3 , R y1 represents a divalent monocyclic group or a divalent condensed polycyclic group, R y2 and R y3 Each independently represents a hydrogen atom or a hydrophilic group, R y2 and R y3 At least one of represents a hydrophilic group, L y1 and L y2 Each independently represents a single bond, a divalent aromatic ring group or a group represented by formula (Y1), wherein when R y1 When it is a divalent monocyclic group, L y1 and L y2 Both represent a divalent aromatic ring group or a group represented by formula (Y1), Formula (Y1)*-R y4 -(R y5 ) n -*, R y4 and R y5 Each independently represents a divalent aromatic ring group, n represents 1 or 2, L y3 and L y4 Each independently represents a single bond, -O-, -S-, an alkylene group, an alkenylene group, an alkynylene group, or a group formed by combining them, In formula (Y1), * represents a bonding position.

7. A circular polarizer comprising: The optically anisotropic film according to any one of claims 1 to 6; and Polarizer.

8. The circular polarizing plate according to claim 7, wherein An angle formed between an in-plane slow axis of the optically anisotropic film and an absorption axis of the polarizer is within a range of 45±5°.

9. A display device comprising: The circular polarizing plate according to claim 7 or 8; and Display components.

10. The display device according to claim 9, wherein The display element is an organic electroluminescent display element.

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