JP2006301605A - Optically anisotropic film, retardation film and its manufacturing method, and liquid crystal display device using retardation film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optically anisotropic film or the like contributing to improvement of the contrast. <P>SOLUTION: In the optically anisotropic film comprising a liquid crystal compound, front retardation Re of the optically anisotropic film is 0 to 20 nm and front leak light when the optically anisotropic film is arranged between two polarizing plates in the cross nicol state upon usage of a diffusing light source is made to be L. The optically anisotropic film satisfies the following relation; 0.000<A<0.200A=(L-X)/d, wherein X represents the front leak light (cd/m<SP>2</SP>) when two polarizing plates are set into the cross nicol state without arranging the optically anisotropic film and d represents a film thickness (μm) of the optically anisotropic film. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technical field of a liquid crystal display device, and more particularly to an in-plane switching (IPS) mode or FFS mode liquid crystal display device that performs display by applying a horizontal electric field to a liquid crystal compound aligned in a horizontal direction. . The present invention also relates to a retardation film that contributes to an improvement in front contrast ratio of a liquid crystal display device such as an IPS mode, and a manufacturing method thereof.

  As a liquid crystal display device, a so-called TN mode, in which a liquid crystal layer in which nematic liquid crystal is twisted and arranged between two orthogonal polarizing plates, and an electric field is applied in a direction perpendicular to the substrate is widely used. In this method, since the liquid crystal rises with respect to the substrate during black display, birefringence due to the liquid crystalline compound occurs when viewed from an oblique direction, and light leakage occurs. In order to solve this problem, a system in which a liquid crystal cell is optically compensated and a light leakage is prevented by using a film in which liquid crystal compounds are hybrid-aligned has been put into practical use. However, even if a liquid crystal compound is used, it is very difficult to completely optically compensate the liquid crystal cell without any problem, resulting in a problem that gradation reversal in the lower direction of the screen cannot be suppressed.

  In order to solve such a problem, a liquid crystal display device using a so-called IPS mode or FFS mode in which a lateral electric field is applied to the liquid crystal, a protrusion formed in the panel by vertically aligning a liquid crystal having a negative dielectric anisotropy, A vertical alignment (VA) mode in which alignment is divided by a slit electrode has been proposed and put into practical use. In recent years, these panels have been developed not only for monitor applications but also for TV applications, and screen brightness has been greatly improved accordingly. For this reason, slight light leakage in the diagonally oblique incidence direction during black display, which has not been considered as a problem in these operation modes, has become apparent as a cause of deterioration in display quality.

  As one means for improving the color tone and the viewing angle of black display, disposing an optical compensation material having birefringence characteristics between the liquid crystal layer and the polarizing plate is also studied in the IPS and FFS modes. For example, by arranging a birefringent medium with optical axes orthogonal to each other to compensate for increase / decrease in retardation of the liquid crystal layer during tilting, the white display or halftone display is obliquely arranged between the substrate and the polarizing plate. It is disclosed that coloring can be improved when viewing directly from (see Patent Document 1). In addition, as a method using an optical compensation film made of a styrene polymer having a negative intrinsic birefringence or a discotic liquid crystalline compound (see Patent Documents 2, 3, and 4), the optical compensation film has a positive birefringence and an optical axis. A method of combining a film in the plane of a film with a film having positive birefringence and an optical axis in the normal direction of the film (see Patent Document 5), biaxial optical compensation sheet having a retardation of half wavelength Using a film having a negative retardation as a protective film of a polarizing plate and providing an optical compensation layer having a positive retardation on this surface (see Patent Document 7) Has been.

Japanese Patent Laid-Open No. 9-80424 Japanese Patent Laid-Open No. 10-54982 JP-A-11-202323 Japanese Patent Laid-Open No. 9-292522 Japanese Patent Laid-Open No. 11-133408 JP-A-11-305217 JP-A-10-307291

  However, when optically compensating an IPS mode or FFS mode liquid crystal cell using an optical compensation sheet made of a stretched birefringent polymer film, it is necessary to use a plurality of films, and as a result, the thickness of the optical compensation sheet increases. This is disadvantageous for thinning the display device. Also, in the method of turning off the liquid crystal by using an optically anisotropic film formed from a discotic liquid crystalline compound that solves this problem, the optical axis of the discotic liquid crystalline compound is aligned horizontally with respect to the substrate surface. Orientation defects are likely to occur, and when used in a liquid crystal display device, light incident from obliquely by diffused light from the backlight is easily depolarized in a film with a large front surface Re and easily escapes to the front surface. Occasionally, light leakage occurred, and even when a retardation film having a low extinction degree was produced, problems such as a decrease in contrast occurred.

  The present invention has been made in view of the above-mentioned problems, and in a liquid crystal display device, particularly a liquid crystal display device in IPS mode or FFS mode, leakage light and color change when observed from 60 ° are kept small, It is an object of the present invention to provide a retardation film that contributes to an improvement in front contrast. Another object of the present invention is to provide an IPS mode liquid crystal display device with low black luminance and improved front contrast ratio. Furthermore, the present invention provides a method for stably producing a retardation film by vertically aligning a rod-like liquid crystalline compound having positive birefringence anisotropy with respect to a substrate in a state where alignment defects are extremely small. This is the issue.

Means for solving the above problems are as follows.
(1) An optically anisotropic film containing a liquid crystalline compound, the front surface Re of the optically anisotropic film is 0 to 20 nm, and the optically anisotropic film is crossed when a diffusion light source is used. An optically anisotropic film satisfying the following formula, where L (cd / m ² ) is the front leakage light when arranged between two Nicol polarizing plates.
Formula 0.00 <A <2.50
A = (L / X) / d
(Where X represents front leakage light (cd / m ² ) when two polarizing plates are placed in a crossed Nicols state without an optically anisotropic film, and d represents the film thickness of the optically anisotropic film ( In addition, the polarizing plate used for leakage light measurement is 0.00000 <X / M <0.00010, and M represents the front luminance (cd / m ² ) of the light source for leakage light measurement.)
(2) A retardation film having the optically anisotropic film according to (1) and having a front Re of 0 to 200 nm.
(3) The retardation film according to (2), wherein the liquid crystalline compound is a rod-like liquid crystalline compound having a polymerizable group.
(4) The method for producing a retardation film according to (3), wherein the rod-like liquid crystalline compound having a polymerizable group is aligned so that its optical axis is perpendicular to the substrate plane, The manufacturing method including the process of polymerizing the said polymeric group in the range of 40 to 80 degreeC, fixing to the orientation state, and forming an optically anisotropic film.
(5) At least a first polarizing film, a first retardation region, a second retardation region, and a liquid crystal cell having a liquid crystal layer sandwiched between a pair of substrates, and the liquid crystalline compound of the liquid crystal cell during black display Is a liquid crystal display device which is aligned substantially parallel to the surfaces of the pair of substrates,
The Re (λ) of the first retardation region is 20 nm to 150 nm, and the Nz value of the first retardation region defined by Nz = Rth / Re + 0.5 is 1.5 to 7, The Re (λ) of the second retardation region is 5 nm or less, the Rth (λ) of the second retardation region is −80 nm to −400 nm, and the liquid crystal display device is (2) or (3) (However, the retardation film may be included in the first retardation region or the second retardation region), and the rod-like liquid crystalline compound is contained in the retardation film. A liquid crystal display device in which molecules are substantially vertically aligned, and further, a transmission axis of the first polarizing film is parallel to a slow axis direction of a liquid crystal compound during black display of the liquid crystal layer.
(6) It further has a second polarizing film having a transmission axis perpendicular to the transmission axis of the first polarizing film, and the first polarizing film and the second polarizing film are the first retardation region and the second position. The liquid crystal display device according to (5), wherein the liquid crystal display device is disposed with the phase difference region and the liquid crystal cell interposed therebetween.
(7) The first polarizing film, the first retardation region, the second retardation region, and the liquid crystal cell are arranged in this order, and the slow axis of the first retardation region is the first phase. The liquid crystal display device according to (5) or (6), which is substantially parallel to the transmission axis of the polarizing film.
(8) The liquid crystal display device according to any one of (5) to (7), wherein the first retardation region is made of a polymer film that exhibits optical anisotropy by stretching.
(9) The first retardation region is a polymer film containing cellulose acylate obtained by substituting a hydroxyl group of a glucose unit constituting cellulose with an acyl group having 2 or more carbon atoms. When the substitution degree of the 2-position hydroxyl group with an acyl group is DS ² , the substitution degree of the 3-position hydroxyl group with an acyl group is DS ³ , and the substitution degree of the 6-position hydroxyl group with an acyl group is DS ⁶ , the following formula (I ) And (II), The liquid crystal display device according to any one of (5) to (8).
(I): 2.0 ≦ DS ² + DS ³ + DS ⁶ ≦ 3.0
(II): DS ⁶ / (DS ² + DS ³ + DS ⁶ ) ≧ 0.315
(10) The liquid crystal display device according to (8) or (9), wherein the polymer film contains at least one retardation developer composed of a rod-like compound or a discotic compound.
(11) A protective film is provided near the liquid crystal layer of the first polarizing film and / or the second polarizing film, and the thickness direction retardation Rth of the protective film is in the range of −40 to 40 nm ( The liquid crystal display device according to any one of 7) to (10).
(12) A protective film is provided on the first polarizing film and / or the second polarizing film on the side close to the liquid crystal layer, and the thickness of the protective film is 60 μm or less. 2. A liquid crystal display device according to item 1.
(13) A protective film is provided near the liquid crystal layer of the first polarizing film and / or the second polarizing film, and the protective film is a cellulose acylate film or a norbornene-based film (6) to (12 The liquid crystal display device according to any one of items 1).
(14) A cellulose acylate film in which a protective film is provided on a side close to the liquid crystal layer of the first polarizing film and / or the second polarizing film, and the protective film satisfies the following formulas (III) and (IV) The liquid crystal display device according to any one of (6) to (13).
(III) 0 ≦ Re ₍₆₃₀₎ ≦ 10 and | Rth ₍₆₃₀₎ | ≦ 25
(IV) | Re ₍₄₀₀₎ −Re ₍₇₀₀₎ | ≦ 10 and | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | ≦ 35
(15) A protective film is provided on the side of the first polarizing film and / or the second polarizing film close to the liquid crystal layer, the protective film is a cellulose acylate film, and the cellulose acylate film is acyl-substituted. In a cellulose acylate having a degree of 2.85 to 3.00, at least one compound that reduces Re (λ) and Rth (λ) is added in a proportion of 0.01 to 30% by mass with respect to the cellulose acylate. The liquid crystal display device according to any one of (6) to (14), which is obtained by addition.

  ADVANTAGE OF THE INVENTION According to this invention, the retardation film which contributes to the improvement of the front contrast of a liquid crystal display device, especially the liquid crystal display device of an IPS mode can be provided. Further, according to the present invention, it is possible to provide an IPS mode liquid crystal display device with low black luminance and improved front contrast ratio. Further, according to the present invention, there is provided a method for stably producing a retardation film by vertically aligning a rod-like liquid crystalline compound having positive birefringence anisotropy with respect to a substrate in a state where alignment defects are extremely small. Can be provided.

  Hereinafter, an embodiment of the liquid crystal display device of the present invention and its constituent members will be described in order. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

  In this specification, “parallel” and “orthogonal” mean that the angle is within a range of strict angle ± 10 ° or less. In this range, an error from a strict angle is preferably less than ± 5 °, and more preferably less than ± 2 °. Further, “substantially” means within a range of less than ± 20 ° from a strict angle. In this range, an error from a strict angle is preferably less than ± 15 °, and more preferably less than ± 10 °. Further, the “slow axis” means a direction in which the refractive index is maximized.

  In the present specification, “optically anisotropic film” refers to a film having at least an optically anisotropic layer. For example, a film in which an optically anisotropic layer is provided on some support may be used, or a film in which the support is peeled off from the film may be used.

  In this specification, unless otherwise specified, the term “polarizing plate” is cut into a size to be incorporated into a long polarizing plate and a liquid crystal device (in this specification, “cutting” includes “punching” and “cutting out”. It is used in the meaning including both of the polarizing plates. In this specification, “polarizing film” and “polarizing plate” are distinguished from each other, but “polarizing plate” means a laminate having a transparent protective film for protecting the polarizing film on at least one surface of the “polarizing film”. It shall be.

  In the present specification, “λ” of Re (λ) and Rth (λ) indicates the measurement wavelength of the retardation. Re represents in-plane retardation, and Rth represents thickness direction retardation.

[Retardation film]
The retardation film of the present invention has an optically anisotropic layer (an optically anisotropic film of the present invention) containing a liquid crystalline compound (preferably a support and an alignment state fixed on the support. A = (L / X) / d (where L is a diffused light source) when disposed between two polarizing plates in a crossed Nicols state. Represents the front leakage light (cd / m ² ) when the optically anisotropic film (optically anisotropic layer) at the time is disposed between two polarizing plates in a crossed Nicol state, and X represents an optically anisotropic film ( Front leakage light (cd / m ² ) when two polarizing plates are placed in a crossed Nicols state without the optically anisotropic layer), d is the optically anisotropic film (optically anisotropic layer) A represented by a film thickness (μm)) is 0.00 <A <2.50. Under the above conditions, 0.00 <A <1.50 is preferable, 0.00 <A <1.00 is more preferable, and 0.00 <A <0.70 is even more preferable.
Furthermore, the optically anisotropic film of the present invention preferably has a front Re of 0 to 20 nm, more preferably 0 to 5 nm.

[Front leakage light measurement]
The front leakage light can be measured using a luminance measuring device. FIG. 1 shows an example of a luminance measuring device, in which a sample of a retardation film is placed between two polarizers in a crossed Nicol state, and the sample is rotated so that transmitted light is minimized. The brightness is measured by the brightness measuring device at the position where the transmitted light is minimized. The measurement is performed in a dark room. In FIG. 1, the polarizing plate on the side close to the light source and the sample are brought into close contact with each other, and the polarizing plate on the light source side is located at a position 15 cm from the sample. In addition, the luminance measuring device is positioned 70 cm from the sample. The measurement is a 1 ° field of view. The diffused light source refers to a light source whose luminance K in the polar angle 60 ° direction with respect to the front luminance S is 0.6 <K / S <1. For example, a Fuji light box 5000 inverter (manufactured by Fuji Photo Film) can be used, and SR-3 (manufactured by Topcon) can be used as a luminance measuring device, for example. By doing so, in addition to the effect that light incident perpendicularly to the film surface is lost, it is possible to measure the effect of being incident obliquely and passing through the front.
When performing the above measurement, the front luminance M measured without a polarizing plate is 2500 cd / m ² , and the front luminance X measured with two polarizing plates in a crossed Nicol state is 0.089 cd / m ² . , X / M = 0.00004 was used.

[Optical characteristics of retardation film]
The present invention includes at least a first polarizing film, a first retardation region, a second retardation region, and a liquid crystal cell in which a liquid crystal layer made of a liquid crystal material is sandwiched between a pair of substrates. A liquid crystal display device in which a liquid crystal compound of a liquid crystal material is aligned substantially parallel to the surfaces of the pair of substrates, wherein Re of the first retardation region is 20 nm to 150 nm, and Nz = Rth / Re + 0 The value Nz of the first retardation region defined by .5 is 1.5 to 7, Re (λ) of the second retardation region is 5 nm or less, Rth is −80 nm to −400 nm, and The transmission axis of one polarizing film is configured to be parallel to the slow axis direction of the liquid crystal compound during black display. By adopting such a configuration, when viewed from an oblique azimuth direction, not only the reduction in contrast caused by the shift of the absorption axes of the two polarizing plates from 90 degrees is achieved, but also polymerization that tends to cause scattering. The reduction in front contrast can be further improved by setting the Re of the second retardation region produced using the liquid crystalline compound to substantially zero. Furthermore, contrast can be further improved by making Rth of the protective film of a polarizing film into the range of -40-40 nm. In addition, by using the optically anisotropic film of the present invention, the second retardation region can be easily produced without using a special vertical alignment film.

  Hereinafter, examples of materials and manufacturing methods used for manufacturing the retardation film of the present invention will be described in detail. The retardation film of the present invention has a support (preferably a transparent support) and an optically anisotropic layer containing a liquid crystal compound fixed in an aligned state thereon. The retardation film of the present invention may have other layers, for example, an alignment film between the support and the optically anisotropic layer. The support may also have some degree of optical anisotropy.

[Optically anisotropic layer (optically anisotropic film)]
In this specification, Re (λ) and Rth (λ) represent in-plane retardation and retardation in the thickness direction at a wavelength λ, respectively. Re (λ) is measured by making light having a wavelength of λ nm incident in the normal direction of the film in KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments). Rth (λ) is Re (λ), with the in-plane slow axis (determined by KOBRA 21ADH or WR) as the tilt axis (rotating axis) (if there is no slow axis, any in-plane The light is incident at a wavelength of λ nm from the inclined direction in steps of 10 degrees from the normal direction to 50 degrees on one side with respect to the film normal direction of KOBRA 21ADH or WR calculates based on the measured retardation value, the assumed average refractive index, and the input film thickness value. The retardation value is measured from any two directions with the slow axis as the tilt axis (rotation axis) (in the absence of the slow axis, the arbitrary direction in the film plane is the rotation axis), and the value Rth can also be calculated from the following formula (1) and formula (2) based on the assumed value of the average refractive index and the input film thickness value. Here, as the assumed value of the average refractive index, the values in the polymer handbook (JOHN WILEY & SONS, INC) and catalogs of various optical films can be used. Those whose average refractive index is not known can be measured with an Abbe refractometer. The average refractive index values of main optical films are exemplified below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), Polystyrene (1.59). By inputting these assumed values of average refractive index and film thickness, KOBRA 21ADH or WR calculates nx, ny, and nz. Nz = (nx−nz) / (nx−ny) is further calculated from the calculated nx, ny, and nz.

注記：上記のRe(θ)は法線方向から角度θ傾斜した方向におけるレターデーション値を表す。
式（２）
Ｒｔｈ＝（（ｎｘ＋ｎｙ）／２−ｎｚ）×ｄ Formula (1)

Note: Re (θ) above represents the retardation value in the direction inclined at an angle θ from the normal direction.
Formula (2)
Rth = ((nx + ny) / 2−nz) × d

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 2 is a schematic diagram showing an example of a pixel region of the liquid crystal display device of the present invention. 3 and 4 are schematic views of an embodiment of the liquid crystal display device of the present invention.
[Liquid Crystal Display]
The liquid crystal display device shown in FIG. 3 includes a first polarizing film 8 and a second polarizing film 21, a retardation film 10 composed of a first retardation area 11 and a second retardation area 12, a first substrate 14, and a second substrate. It has a substrate 18 and a liquid crystal layer 16 sandwiched between the substrates. The first polarizing film 8 and the second polarizing film 21 are sandwiched between the first polarizing plate protective films 7a and 7b and the second polarizing plate protective films 20a and 20b.

  In the liquid crystal display device of FIG. 2, the liquid crystal cell includes a first substrate 14 and a second substrate 18 and a liquid crystal layer 16 sandwiched between them. The product Δn · d of the thickness d (μm) of the liquid crystal layer and the refractive index anisotropy Δn is optimal in the range of 0.2 to 0.4 μm for the IPS type having no twisted structure in the transmission mode. In this range, the white display luminance is high and the black display luminance is small, so that a bright and high-contrast display device can be obtained. An alignment film (not shown) may be formed on the surfaces of the first substrate 14 and the second substrate 18 that are in contact with the liquid crystal layer 16, and the liquid crystalline compound is applied to the surface of the first substrate 14 or the second substrate 18. The alignment direction of the liquid crystal compound in the no-voltage application state or the low-application state is controlled by the first substrate rubbing treatment direction 15 and the second substrate rubbing treatment direction 19 applied on the alignment film. ing. In addition, an electrode (not shown in FIG. 2) capable of applying a voltage to the liquid crystal compound is formed on the inner surface of the first substrate 14 or the second substrate 18.

  FIG. 2 schematically shows the orientation of the liquid crystal compound in one pixel region of the liquid crystal layer 16. FIG. 2 shows the alignment of the liquid crystal compound in the region of an extremely small area corresponding to one pixel of the liquid crystal layer 16 formed on the rubbing direction 4 of the alignment film formed on the inner surface of the substrate and on the inner surface of the substrate. It is the schematic diagram shown with the pixel electrode 2 and the display electrode 3 which can apply a voltage to the liquid crystalline compound. When active driving is performed using a nematic liquid crystal having positive dielectric anisotropy as a field effect liquid crystal, the alignment direction of the liquid crystalline compound in a no-voltage applied state or a low applied state is 5a and 5b. Black display is obtained. When applied between the electrodes 2 and 3, the liquid crystal compound changes its orientation direction in the 6a and 6b directions according to the voltage. Normally, bright display (white display) is performed in this state.

In FIG. 3 again, the polarization transmission axis 9 of the first polarizing film and the polarization transmission axis 22 of the second polarizing film are arranged orthogonally. The slow axis 13 of the first retardation region 11 is parallel to the polarization transmission axis 9 of the first polarizing film and the slow axis direction 17 of the liquid crystalline compound in the liquid crystal layer 16 during black display. Here, the first retardation region can be, for example, a transparent support, and the second retardation region can be an optically anisotropic layer.
The liquid crystal display device shown in FIG. 3 shows a configuration in which the first polarizing film 8 is sandwiched between the two first polarizing protective films 7a and 7b. However, the first polarizing protective film 7b is not an essential requirement. Absent. When there is no protective film 7b, it is preferable that a part or all of the first retardation region 11 has a characteristic that can also function as the protective film 7b of the polarizing film. The second polarizing film 21 is also sandwiched between the two protective films 20a and 20b, but the protective film 20a on the side close to the liquid crystal layer 16 may not be provided. In the aspect of FIG. 2, the first retardation region 11 and the second retardation region 12 may be disposed between the liquid crystal cell and the viewing-side polarizing film with reference to the position of the liquid crystal cell. And it may be arrange | positioned between the liquid crystal cell and the polarizing film of the back side. In this embodiment, in any configuration, it is preferable to arrange the second retardation region so as to be closer to the liquid crystal cell.

  Another embodiment of the present invention is shown in FIG. In the liquid crystal display device of FIG. 4, the second retardation region 12 is disposed between the first polarizing film 8 and the first retardation region 11. In the liquid crystal display device of FIG. 3, the first polarizing plate protective film 7b may be omitted. When there is no protective film 7b, it is preferable that a part or all of the second retardation region 12 has a characteristic that can also function as the protective film 7b of the polarizing film. The second polarizing film 21 is also sandwiched between the two second polarizing plate protective films 20a and 20b. However, the second polarizing plate protective film 20a on the side close to the liquid crystal layer 16 may be omitted. In the embodiment shown in FIG. 4, the first retardation region 11 has a slow axis 13 in the slow axis direction 17 of the liquid crystal compound in the liquid crystal layer 16 in the liquid crystal layer 16 during black display with the transmission axis 9 of the first polarizing film. It arrange | positions so that it may become orthogonal. In the aspect of FIG. 4, the first retardation region 11 and the second retardation region 12 may be disposed between the liquid crystal cell and the viewing-side polarizing film with reference to the position of the liquid crystal cell. And it may be arranged between the liquid crystal cell and the polarizing film on the back side. In the present embodiment, in any configuration, the first retardation region is disposed closer to the liquid crystal cell.

  4 and 3 show the mode of the transmission mode display device including the upper polarizing plate and the lower polarizing plate, the present invention is a mode of the reflection mode including only one polarizing plate. In such a case, since the optical path in the liquid crystal cell is doubled, the optimum value of Δn · d is about the above half value. Further, the liquid crystal cell used in the present invention is not limited to the IPS mode, and any liquid crystal display device can be used as long as the liquid crystal compound is aligned substantially parallel to the surfaces of the pair of substrates during black display. Can also be suitably used. Examples thereof include a ferroelectric liquid crystal display device, an antiferroelectric liquid crystal display device, and an ECB type liquid crystal display device.

  The liquid crystal display device of the present invention is not limited to the configuration shown in FIGS. 2 to 4 and may include other members. For example, a color filter may be disposed between the liquid crystal layer and the polarizing film. Further, an antireflection treatment or a hard coat may be applied to the surface of the protective film of the polarizing film. Moreover, you may use what gave electroconductivity to the structural member. When used as a transmissive type, a cold cathode or a hot cathode fluorescent tube, or a backlight having a light emitting diode, a field emission element, or an electroluminescent element as a light source can be disposed on the back surface. In this case, the arrangement of the backlight may be on the upper side or the lower side in FIGS. In addition, a reflective polarizing plate, a diffusion plate, a prism sheet, or a light guide plate can be disposed between the liquid crystal layer and the backlight. In addition, as described above, the liquid crystal display device of the present invention may be of a reflective type. In such a case, only one polarizing plate may be disposed on the observation side, and the back side of the liquid crystal cell or the lower side of the liquid crystal cell. A reflective film is disposed on the inner surface of the substrate. Of course, it is also possible to provide a front light using the light source on the liquid crystal cell observation side.

  The liquid crystal display device of the present invention includes an image direct view type, an image projection type, and a light modulation type. The present invention is particularly effective when applied to an active matrix liquid crystal display device using a three-terminal or two-terminal semiconductor element such as a thin film transistor (TFT) or a metal insulator metal (MIM). Of course, a mode applied to a passive matrix liquid crystal display device called time-division driving is also effective.

  Hereinafter, preferred optical characteristics of various members usable in the liquid crystal display device of the present invention, materials used for the members, manufacturing methods thereof, and the like will be described in detail.

[First phase difference region]
The first retardation region included in the liquid crystal display device of the present invention has Re (λ) of 20 nm to 150 nm, and in order to effectively reduce the light leakage in the oblique direction, the Re of the first retardation region. (Λ) is more preferably 40 nm to 115 nm, and further preferably 60 nm to 95 nm. Further, Nz defined by Nz = Rth / Re + 0.5 using Rth (λ) in the thickness direction of the first retardation region is 1.5 to 7, and the light leakage in the oblique direction is effectively prevented. In order to reduce, Nz of the first retardation region is more preferably 2.0 to 5.5, and further preferably 2.5 to 4.5.

  As long as the first retardation region has the optical characteristics, the material and form thereof are basically not particularly limited. For example, a polymer film (preferably a retardation film made of a birefringent polymer film), a film obtained by heating and stretching a polymer compound on a support, and a low-molecular or polymer liquid crystalline compound applied on a support or Any of retardation films having a retardation layer formed by transferring can be used. Moreover, each can also be laminated | stacked and used.

  The birefringent polymer film is preferably a film having excellent controllability of birefringence characteristics, transparency and heat resistance. In this case, the polymer material to be used is not particularly limited as long as it is a polymer capable of achieving uniform biaxial orientation, but is preferably a conventionally known material that can be formed by a solution casting method or an extrusion method, and a norbornene-based material. Examples include polymers, polycarbonate polymers, polyarylate polymers, polyester polymers, aromatic polymers such as polysulfone, cellulose acylate, or polymers obtained by mixing two or more of these polymers. It is done.

Biaxial orientation of the birefringent polymer film can be achieved by using a film made of the thermoplastic resin produced by an appropriate method such as an extrusion molding method or a casting film forming method, for example, a longitudinal stretching method using a roll, a lateral stretching method using a tenter, This can be achieved by performing a stretching process by an axial stretching method or the like. In the longitudinal stretching method using the roll, a heating method such as a method using a heating roll, a method of heating an atmosphere, or a method using them in combination can be employed. In addition, the biaxial stretching method using a tenter can employ a simultaneous biaxial stretching method using an all tenter method or a sequential biaxial stretching method using a roll tenter method.
Moreover, a thing with little orientation nonuniformity and phase difference nonuniformity is preferable. Although the thickness can be determined by a phase difference or the like, it is generally preferably 1 to 300 μm, more preferably 10 to 200 μm, and further preferably 20 to 150 μm from the viewpoint of thinning.

  As the norbornene-based polymer, norbornene and its derivatives, tetracyclododecene and its derivatives, dicyclopentadiene and its derivatives, methanotetrahydrofluorene and its monomers as a main component of a monomer polymer, Ring-opening polymer of norbornene-based monomer, ring-opening copolymer of norbornene-based monomer and other monomer capable of ring-opening copolymerization, addition polymer of norbornene-based monomer, copolymerizable with norbornene-based monomer Examples include addition copolymers with other monomers and hydrogenated products thereof. Among these, from the viewpoints of heat resistance, mechanical strength, and the like, a ring-opening polymer hydride of a norbornene monomer is most preferable. The molecular weight of the norbornene-based polymer, the monocyclic olefin polymer, or the cyclic conjugated diene polymer is appropriately selected according to the purpose of use, but is a cyclohexane solution (a toluene solution if the polymer resin does not dissolve). Polyisoprene or polystyrene-converted weight average molecular weight measured by gel permeation chromatography, preferably 5,000 to 500,000, more preferably 8,000 to 200,000, still more preferably 10,000 to 100 When it is in the range of 1,000, the mechanical strength of the film (A) and the moldability are highly balanced and suitable. Typical polymers include those described in JP2003-327800A and JP2004233604A.

  The acyl group of cellulose acylate may be an aliphatic group or an aromatic group, and is not particularly limited. They are, for example, cellulose alkylcarbonyl ester, alkenylcarbonyl ester or aromatic carbonyl ester, aromatic alkylcarbonyl ester, etc., each of which may further have a substituted group, and the total number of carbon atoms is 22 or less. An ester group is preferred. As these preferable cellulose acylates, acyl groups having a total carbon atom number of 22 or less in the ester part (for example, acetyl group, propionyl group, butyroyl group, barrel group, heptanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group) Group, hexadecanoyl group, octadecanoyl group, etc.), arylcarbonyl group (acrylic group, methacrylic group, etc.), allylcarbonyloxy (benzoyl group, naphthaloyl group, etc.), and cinnamoyl group. Among these, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate stearate, cellulose acetate benzoate, etc. are not particularly limited in the case of mixed esters, but preferably acetate is the total ester. It is preferable that it is 30 mol% or more.

  Among these, cellulose acylate is preferred, and photographic grades are particularly preferred, and commercially available photographic grades can be obtained with satisfactory quality such as viscosity average degree of polymerization and substitution degree. Manufacturers of photographic grade cellulose triacetate include Daicel Chemical Industries, Ltd. (for example, LT-20, 30, 40, 50, 70, 35, 55, 105) and Eastman Chemical (for example, CAB-551). 0.01, CAB-551-0.02, CAB-500-5, CAB-381-0.5, CAB-381-02, CAB-381-20, CAB-321-0.2, CAP-504 0.2, CAP-482-20, CA-398-3, etc.), Coatles, Hoechst, etc., any of which can use photographic grade cellulose acylate. In addition, a plasticizer, a surfactant, a retardation modifier, a UV absorber, and the like can be mixed for the purpose of controlling the mechanical properties and optical properties of the film. Details of these additives are described in, for example, JP-A Nos. 2002-277632 and 2002-182215.

As a particularly preferred cellulose acylate, the total acyl substitution degree, that is, DS ² + DS ³ + DS ⁶ is 2.00 to 3.00, and the 6-position substitution rate is D ⁶ S / (DS ² + DS ³ + DS ⁶ ). Is cellulose acylate having a value of 0.315 or more. DS ² + DS ³ + DS ⁶ is more preferably 2.22 to 2.90, and particularly preferably 2.40 to 2.82. Further, D ⁶ S / (DS ² + DS ³ + DS ⁶ ) is more preferably 0.322 or more, and particularly preferably 0.324 to 0.340. Here, DS ² is the degree of substitution of the hydroxyl group at the 2-position of the glucose unit with an acyl group (hereinafter also referred to as “degree of acyl substitution at the 2-position”), and DS ³ is the degree of substitution of the hydroxyl group at the 3-position with an acyl group ( Hereinafter, it is also referred to as “acyl substitution degree at the 3-position”), and DS ⁶ is the substitution degree of the hydroxyl group at the 6-position with an acyl group (hereinafter also referred to as “acyl substitution degree at the 6-position”).

(Additive)
In the composition for forming the cellulose acylate used in the present invention, various additives (for example, plasticizers, ultraviolet inhibitors, deterioration inhibitors, retardation (optical anisotropy)) according to the use in each preparation step. ) Modifiers, fine particles, release promoters, infrared absorbers, etc.), which can be solid or oily. That is, the melting point and boiling point are not particularly limited. For example, mixing of ultraviolet absorbing material at 20 ° C. or lower and 20 ° C. or higher, and similarly, mixing of a plasticizer is described in, for example, JP-A-2001-151901. Examples of the peeling accelerator include citric acid ethyl esters. Furthermore, infrared absorbing dyes are described, for example, in JP-A No. 2001-194522. Moreover, the addition time may be added at any time in the dope preparation step, but may be added by adding an additive to the final preparation step of the dope preparation step. Furthermore, the amount of each material added is not particularly limited as long as the function is manifested. Moreover, when a cellulose acylate film is formed from a multilayer, the kind and addition amount of the additive of each layer may differ. For example, it is described in Japanese Patent Application Laid-Open No. 2001-151902, but these are conventionally known techniques. It is preferable that the glass transition temperature (Tg) of the cellulose acylate film is 80 to 180 ° C. and the elastic modulus measured with a tensile tester is 1500 to 3000 MPa, depending on the selection of the types and addition amounts of these additives.
Further, for these details, materials described in detail on page 16 and after in the Invention Association Public Technical Bulletin No. 2001-1745 (issued on March 15, 2001, Invention Association) are preferably used.

(Plasticizer)
The film constituting the first retardation region preferably contains a plasticizer. The plasticizer that can be used is not particularly limited, but in the phosphate ester system, triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, etc. For phthalate esters, diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, etc. Less cellulose acylate such as ethyl glycolate, methyl phthalyl ethyl glycolate, butyl phthalyl butyl glycolate Specific preferred to singly or in combination one. Two or more plasticizers may be used in combination as required.

(Retardation expression agent)
In the present invention, in order to express the retardation value, the film constituting the first retardation region may contain a retardation developer. The retardation developer is not particularly defined, but is preferably a rod-like compound or a discotic compound, and more preferably a compound having at least two aromatic rings. The retardation enhancer is preferably used in the range of 0.05 to 20 parts by mass, and in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass of the polymer constituting the first retardation region. More preferably, it is more preferably used in the range of 0.2 to 5 parts by mass, and most preferably in the range of 0.5 to 2 parts by mass. Two or more retardation developing agents may be used in combination.
The retardation developer preferably has a maximum absorption in the wavelength region of 250 to 400 nm, and preferably has substantially no absorption in the visible region.

The aromatic ring that the retardation developer may have includes an aromatic hetero ring in addition to the aromatic hydrocarbon ring. The aromatic hydrocarbon ring is particularly preferably a 6-membered ring (that is, a benzene ring). The aromatic heterocycle is generally an unsaturated heterocycle. The aromatic heterocycle is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring. Aromatic heterocycles generally have the most double bonds. As the hetero atom, a nitrogen atom, an oxygen atom and a sulfur atom are preferable, and a nitrogen atom is particularly preferable. Examples of aromatic heterocycles include furan ring, thiophene ring, pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, pyrazole ring, furazane ring, triazole ring, pyran ring, pyridine ring , Pyridazine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring.
As the aromatic ring, benzene ring, furan ring, thiophene ring, pyrrole ring, oxazole ring, thiazole ring, imidazole ring, triazole ring, pyridine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring are preferable, In particular, a 1,3,5-triazine ring is preferably used. Specifically, for example, compounds disclosed in JP-A No. 2001-166144 are preferably used.

The number of aromatic rings contained in the retardation enhancer is preferably 2 to 20, more preferably 2 to 12, still more preferably 2 to 8, and most preferably 2 to 6. preferable.
The bond relationship between two aromatic rings can be classified into (a) a condensed ring, (b) a direct bond with a single bond, and (c) a bond through a linking group (for aromatic rings). , Spiro bonds cannot be formed). The connection relationship may be any of (a) to (c).

  Examples of the condensed ring (a condensed ring of two or more aromatic rings) include an indene ring, a naphthalene ring, an azulene ring, a fluorene ring, a phenanthrene ring, an anthracene ring, an acenaphthylene ring, a biphenylene ring, a naphthacene ring, Pyrene ring, indole ring, isoindole ring, benzofuran ring, benzothiophene ring, indolizine ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring, purine ring, indazole ring, chromene ring, quinoline ring, isoquinoline Ring, quinolidine ring, quinazoline ring, cinnoline ring, quinoxaline ring, phthalazine ring, pteridine ring, carbazole ring, acridine ring, phenanthridine ring, xanthene ring, phenazine ring, phenothiazine ring, phenoxathiin ring, phenoxazine ring and thiant It includes emissions ring. Naphthalene ring, azulene ring, indole ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring and quinoline ring are preferred.

  The single bond (b) is preferably a bond between carbon atoms of two aromatic rings. Two aromatic rings may be bonded with two or more single bonds to form an aliphatic ring or a non-aromatic heterocyclic ring between the two aromatic rings.

The linking group in (c) is also preferably bonded to carbon atoms of two aromatic rings. The linking group is preferably an alkylene group, an alkenylene group, an alkynylene group, —CO—, —O—, —NH—, —S—, or a combination thereof. Examples of linking groups composed of combinations are shown below. In addition, the relationship between the left and right in the following examples of the linking group may be reversed.
c1: -CO-O-
c2: —CO—NH—
c3: -alkylene group -O-
c4: —NH—CO—NH—
c5: —NH—CO—O—
c6: —O—CO—O—
c7: -O-alkylene group -O-
c8: —CO-alkenylene group—
c9: -CO-alkenylene group -NH-
c10: -CO-alkenylene group -O-
c11: -alkylene group-CO-O-alkylene group-O-CO-alkylene group-
c12: -O-alkylene group -CO-O-alkylene group -O-CO-alkylene group -O-
c13: -O-CO-alkylene group -CO-O-
c14: —NH—CO-alkenylene group—
c15: -O-CO-alkenylene group-

The aromatic ring and the linking group may have a substituent.
Examples of substituents include halogen atoms (F, Cl, Br, I, etc.), hydroxyl groups, carboxyl groups, cyano groups, amino groups, nitro groups, sulfo groups, carbamoyl groups, sulfamoyl groups, ureido groups, alkyl groups, Alkenyl group, alkynyl group, aliphatic acyl group, aliphatic acyloxy group, alkoxy group, alkoxycarbonyl group, alkoxycarbonylamino group, alkylthio group, alkylsulfonyl group, aliphatic amide group, aliphatic sulfonamide group, aliphatic substituted amino group Groups, aliphatic substituted carbamoyl groups, aliphatic substituted sulfamoyl groups, aliphatic substituted ureido groups and non-aromatic heterocyclic groups.

It is preferable that the alkyl group has 1 to 8 carbon atoms. A chain alkyl group is preferable to a cyclic alkyl group, and a linear alkyl group is particularly preferable. The alkyl group may further have a substituent (for example, a hydroxy group, a carboxy group, an alkoxy group, an alkyl-substituted amino group). Examples of alkyl groups (including substituted alkyl groups) include methyl, ethyl, n-butyl, n-hexyl, 2-hydroxyethyl, 4-carboxybutyl, 2-methoxyethyl, and 2- A diethylaminoethyl group is included.
The alkenyl group preferably has 2 to 8 carbon atoms. A chain alkenyl group is preferable to a cyclic alkenyl group, and a linear alkenyl group is particularly preferable. The alkenyl group may further have a substituent. Examples of the alkenyl group include a vinyl group, an allyl group, and a 1-hexenyl group.
The alkynyl group preferably has 2 to 8 carbon atoms. A chain alkynyl group is preferable to a cyclic alkynyl group, and a linear alkynyl group is particularly preferable. The alkynyl group may further have a substituent. Examples of the alkynyl group include ethynyl group, 1-butynyl group and 1-hexynyl group.

The number of carbon atoms in the aliphatic acyl group is preferably 1-10. Examples of the aliphatic acyl group include an acetyl group, a propanoyl group, and a butanoyl group.
The number of carbon atoms in the aliphatic acyloxy group is preferably 1-10. Examples of the aliphatic acyloxy group include an acetoxy group.
The number of carbon atoms of the alkoxy group is preferably 1-8. The alkoxy group may further have a substituent (for example, an alkoxy group). Examples of the alkoxy group (including a substituted alkoxy group) include a methoxy group, an ethoxy group, a butoxy group, and a methoxyethoxy group.
The number of carbon atoms of the alkoxycarbonyl group is preferably 2-10. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group.
The number of carbon atoms of the alkoxycarbonylamino group is preferably 2-10. Examples of the alkoxycarbonylamino group include a methoxycarbonylamino group and an ethoxycarbonylamino group.

The alkylthio group preferably has 1 to 12 carbon atoms. Examples of the alkylthio group include a methylthio group, an ethylthio group, and an octylthio group.
The alkylsulfonyl group preferably has 1 to 8 carbon atoms. Examples of the alkylsulfonyl group include a methanesulfonyl group and an ethanesulfonyl group.
The number of carbon atoms in the aliphatic amide group is preferably 1-10. Examples of the aliphatic amide group include an acetamide group.
The number of carbon atoms of the aliphatic sulfonamide group is preferably 1-8. Examples of the aliphatic sulfonamido group include a methanesulfonamido group, a butanesulfonamido group, and an n-octanesulfonamido group.
The number of carbon atoms of the aliphatic substituted amino group is preferably 1-10. Examples of the aliphatic substituted amino group include a dimethylamino group, a diethylamino group, and a 2-carboxyethylamino group.
The number of carbon atoms in the aliphatic substituted carbamoyl group is preferably 2-10. Examples of the aliphatic substituted carbamoyl group include a methylcarbamoyl group and a diethylcarbamoyl group.
The number of carbon atoms in the aliphatic substituted sulfamoyl group is preferably 1-8. Examples of the aliphatic substituted sulfamoyl group include a methylsulfamoyl group and a diethylsulfamoyl group.
The number of carbon atoms in the aliphatic substituted ureido group is preferably 2-10. Examples of the aliphatic substituted ureido group include a methylureido group.
Examples of the non-aromatic heterocyclic group include a piperidino group and a morpholino group.
The molecular weight of the retardation developer is preferably 300 to 800.

  In the present invention, besides the above compounds, rod-shaped compounds having a linear molecular structure can also be preferably used. The linear molecular structure means that the molecular structure of the rod-like compound is linear in the most thermodynamically stable structure. The most thermodynamically stable structure can be obtained by crystal structure analysis or molecular orbital calculation. For example, molecular orbital calculation can be performed using molecular orbital calculation software (for example, WinMOPAC2000, manufactured by Fujitsu Limited) to obtain a molecular structure that minimizes the heat of formation of a compound. The molecular structure being linear means that in the thermodynamically most stable structure obtained by calculation as described above, the angle of the main chain constituting the molecular structure is 140 degrees or more.

As the rod-shaped compound having at least two aromatic rings, a compound represented by the following general formula (1) is preferable.
Formula (1): Ar ¹ -L ¹ -Ar ²
In the general formula (1), Ar ¹ and Ar ² are each independently an aromatic group. The aromatic group here includes an aryl group (aromatic hydrocarbon group), a substituted aryl group, an aromatic heterocyclic group, and a substituted aromatic heterocyclic group. An aryl group and a substituted aryl group are more preferable than an aromatic heterocyclic group and a substituted aromatic heterocyclic group. The heterocycle of the aromatic heterocyclic group is preferably an unsaturated compound. The aromatic heterocycle is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring. Aromatic heterocycles generally have the most double bonds. As a hetero atom, a nitrogen atom, an oxygen atom or a sulfur atom is preferable, and a nitrogen atom or a sulfur atom is more preferable.
As the aromatic ring of the aromatic group, a benzene ring, a furan ring, a thiophene ring, a pyrrole ring, an oxazole ring, a thiazole ring, an imidazole ring, a triazole ring, a pyridine ring, a pyrimidine ring and a pyrazine ring are preferable, and a benzene ring is particularly preferable. .

Examples of the substituent of the substituted aryl group and the substituted aromatic heterocyclic group include a halogen atom (F,
Cl, Br, I), hydroxyl group, carboxyl group, cyano group, amino group, alkylamino group (for example, methylamino group, ethylamino group, butylamino group, dimethylamino group), nitro group, sulfo group, carbamoyl group Alkylcarbamoyl group (for example, N-methylcarbamoyl group, N-ethylcarbamoyl group, N, N-dimethylcarbamoyl group), sulfamoyl group, alkylsulfamoyl group (for example, N-methylsulfamoyl group, N-ethylsulfamoyl group) Famoyl group, N, N-dimethylsulfamoyl group), ureido group, alkylureido group (for example, N-methylureido group, N, N-dimethylureido group, N, N, N′-trimethylureido group), Alkyl groups (eg, methyl, ethyl, propyl, butyl, pentyl, heptyl Group, octyl group, isopropyl group, s-butyl group, tert-amyl group, cyclohexyl group, cyclopentyl group), alkenyl group (for example, vinyl group, allyl group, hexenyl group), alkynyl group (for example, ethynyl group, butynyl group) Group), acyl group (for example, formyl group, acetyl group, butyryl group, hexanoyl group, lauryl group), acyloxy group (for example, acetoxy group, butyryloxy group, hexanoyloxy group, lauryloxy group), alkoxy group (for example, Methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, heptyloxy group, octyloxy group), aryloxy group (for example, phenoxy group), alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, propoxy) Carbonyl group, buto Sicarbonyl group, pentyloxycarbonyl group, heptyloxycarbonyl group), aryloxycarbonyl group (for example, phenoxycarbonyl group), alkoxycarbonylamino group (for example, butoxycarbonylamino group, hexyloxycarbonylamino group), alkylthio group (for example, , Methylthio group, ethylthio group, propylthio group, butylthio group, pentylthio group, heptylthio group, octylthio group), arylthio group (for example, phenylthio group), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group, Butylsulfonyl group, pentylsulfonyl group, heptylsulfonyl group, octylsulfonyl group), amide group (eg, acetamide group, butylamide group, hexylamide group, lauryl group) Ruamido group) and a non-aromatic Hajime Tamaki (e.g., morpholyl group, pyrazinyl group) include.

Among these, preferred substituents include halogen atoms, cyano groups, carboxyl groups, hydroxyl groups, amino groups, alkylamino groups, acyl groups, acyloxy groups, amide groups, alkoxycarbonyl groups, alkoxy groups, alkylthio groups, and alkyl groups. Can be mentioned.
The alkyl part and the alkyl group of the alkylamino group, alkoxycarbonyl group, alkoxy group and alkylthio group may further have a substituent. Examples of the alkyl moiety and the substituent of the alkyl group include halogen atom, hydroxyl group, carboxyl group, cyano group, amino group, alkylamino group, nitro group, sulfo group, carbamoyl group, alkylcarbamoyl group, sulfamoyl group, alkylsulfur group. Famoyl group, ureido group, alkylureido group, alkenyl group, alkynyl group, acyl group, acyloxy group, alkoxy group, aryloxy group, alkoxycarbonyl group, aryloxycarbonyl group, alkoxycarbonylamino group, alkylthio group, arylthio group, Alkylsulfonyl groups, amide groups and non-aromatic heterocyclic groups are included. As the substituent for the alkyl moiety and the alkyl group, a halogen atom, a hydroxyl group, an amino group, an alkylamino group, an acyl group, an acyloxy group, an acylamino group, an alkoxycarbonyl group, and an alkoxy group are preferable.

In the general formula (1), L ¹ is a divalent linking group selected from an alkylene group, an alkenylene group, an alkynylene group, —O—, —CO— and a combination thereof. The alkylene group may have a cyclic structure. As the cyclic alkylene group, a cyclohexylene group is preferable, and a 1,4-cyclohexylene group is particularly preferable. As the chain alkylene group, a linear alkylene group is more preferable than a branched alkylene group.
The number of carbon atoms of the alkylene group is preferably 1-20, more preferably 1-15, still more preferably 1-10, still more preferably 1-8, and most preferably 1-6. It is.

The alkenylene group and alkynylene group preferably have a chain structure rather than a cyclic structure, and more preferably have a linear structure rather than a branched chain structure.
The alkenylene group and the alkynylene group preferably have 2 to 10 carbon atoms, more preferably 2 to 8, more preferably 2 to 6, still more preferably 2 to 4, and most preferably 2. (Vinylene group or ethynylene group).
The arylene group preferably has 6 to 20 carbon atoms, more preferably 6 to 16, and still more preferably 6 to 12.

In the molecular structure of the general formula (1), the angle formed by Ar ¹ and Ar ² across L ¹ is preferably 140 degrees or more.
As the rod-like compound, a compound represented by the following formula (2) is more preferable.
Formula ^{(2): Ar 1 -L 2} -X-L 3 -Ar 2
In the general formula (2), Ar ¹ and Ar ² are each independently an aromatic group. The definition and examples of the aromatic group are the same as those for Ar ¹ and Ar ^{2 in} formula (I).

In the general formula (2), L ² and L ³ are each independently a divalent linking group selected from an alkylene group, —O—, —CO—, and a group consisting of a combination thereof.
The alkylene group preferably has a chain structure rather than a cyclic structure, and more preferably has a linear structure rather than a branched chain structure.
The alkylene group preferably has 1 to 10 carbon atoms, more preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and 1 or 2 (methylene group). Or ethylene group).
L ² and L ³ are particularly preferably —O—CO— or —CO—O—.

In the general formula (2), X represents a 1,4-cyclohexylene group, a vinylene group or an ethynylene group.
Specific examples of the compound represented by the general formula (1) are shown below.

  Specific examples (1) to (34), (41), and (42) have two asymmetric carbon atoms at the 1-position and the 4-position of the cyclohexane ring. However, since the specific examples (1), (4) to (34), (41), and (42) have a symmetrical meso type molecular structure, there are no optical isomers (optical activity), and geometric isomers (trans Type and cis type). The trans type (1-trans) and cis type (1-cis) of specific example (1) are shown below.

As described above, the rod-like compound preferably has a linear molecular structure. Therefore, the trans type is preferable to the cis type.
Specific examples (2) and (3) have optical isomers (a total of four isomers) in addition to geometric isomers. As for geometric isomers, the trans type is similarly preferable to the cis type. The optical isomer is not particularly superior or inferior, and may be D, L, or a racemate.
In specific examples (43) to (45), the central vinylene bond includes a trans type and a cis type. For the same reason as above, the trans type is preferable to the cis type.

In addition, the preferred agent that can be used in the present invention is shown below.

Moreover, in this invention, it is also preferable to use together 2 or more types of rod-shaped compounds whose maximum absorption wavelength ((lambda) max) is shorter than 250 nm in the ultraviolet absorption spectrum of the composition for polymer film formation.
The rod-like compound can be synthesized with reference to methods described in literature. References include Mol. Cryst. Liq. Cryst., 53, 229 (1979), 89, 93 (1982), 145, 111 (1987), 170, 43 Page (1989), J. Am. Chem. Soc., 113, 1349 (1991), 118, 5346 (1996), 92, 1582 (1970), J. Org Chem., 40, 420 (1975), Tetrahedron, 48, 16, 3437 (1992).
The addition amount of the retardation enhancer is preferably 0.1 to 30% by mass, and more preferably 0.5 to 20% by mass of the amount of the polymer.

  In particular, the retardation developing agent that is an aromatic compound is preferably used in the range of 0.01 to 20 parts by mass with respect to 100 parts by mass of cellulose acetate. The aromatic compound is more preferably used in the range of 0.05 to 15 parts by mass and more preferably in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass of the cellulose acetate. Two or more kinds of compounds may be used in combination.

In producing the polymer film, as a method of forming the transparent resin into a sheet or film, for example, either a heat-melt molding method or a solution casting method can be used. The hot melt molding method can be further classified into an extrusion molding method, a press molding method, an inflation molding method, an injection molding method, a blow molding method, a stretch molding method, etc. Among these methods, mechanical strength, surface In order to obtain a film excellent in accuracy and the like, the extrusion molding method, the inflation molding method, and the press molding method are preferable, and the extrusion molding method is most preferable. The molding conditions are appropriately selected depending on the purpose of use and the molding method. In the case of the heat-melt molding method, the cylinder temperature is preferably set in the range of preferably 100 to 400 ° C, more preferably 150 to 350 ° C. The thickness of the polymer film is preferably 10 to 300 μm, more preferably 30 to 200 μm.
When the glass transition temperature of the transparent resin is Tg, the stretching of the polymer film is preferably at least in the temperature range of Tg-30 ° C to Tg + 60 ° C, more preferably in the temperature range of Tg-10 ° C to Tg + 50 ° C. It is preferably carried out in one direction at a draw ratio of 1.01 to 2 times. The stretching direction may be at least one direction, but when the polymer film is obtained by extrusion molding, the direction is preferably the resin mechanical flow direction (extrusion direction). Is preferably a free shrink uniaxial stretching method, a fixed width uniaxial stretching method, a biaxial stretching method, or the like. The optical characteristics can be controlled by controlling the draw ratio and the heating temperature.

[Second phase difference region]
In the second retardation region of the liquid crystal display device of the present invention, Re is 5 nm or less, and the retardation Rth (λ) in the thickness direction of the second retardation region is −80 nm to −400 nm. A preferable range of Re (λ) is preferably 3 nm or less, and more preferably 2 nm or less.
A more preferable range of Rth (λ) in the second retardation region varies depending on the optical characteristics of other optical members, and in particular, a protective film (for example, a cellulose acetate film or norbornene) of a polarizing film located closer to the second retardation region. Rth (λ) of the second retardation region is −100 nm to −340 nm in order to effectively reduce the light leakage in the oblique direction. Is more preferable, and -120 nm to -270 nm is more preferable.

  The second retardation region preferably includes the optically anisotropic film of the present invention. In the optically anisotropic film, the rod-like liquid crystal compound molecules are preferably fixed in a vertically aligned state. The second retardation region may be composed of only the optical anisotropic film or a plurality of optical anisotropic films. Further, the second retardation region may be configured so that the entire laminated body of the support and the optically anisotropic film satisfies the optical characteristics. As the rod-like liquid crystal compound to be used, those that take a nematic liquid crystal phase, a smectic liquid crystal phase, and a lyotropic liquid crystal phase in a temperature range in which the orientation is fixed are preferably used. In order to obtain a uniform alignment state, a liquid crystal exhibiting a nematic phase is preferable. In particular, in the presence of an additive, for the rod-like liquid crystalline compound that is in the above liquid crystal state in an appropriate orientation temperature range, an optically anisotropic film using a composition containing the additive and the rod-like liquid crystalline compound is used. It is also preferable to form

  The term “substantially perpendicular” means that the angle formed between the film surface and the director of the rod-like liquid crystal compound is in the range of 70 ° to 90 °. These liquid crystalline compounds may be aligned obliquely or may be changed so that the inclination angle gradually changes (hybrid alignment). Even in the case of oblique alignment or hybrid alignment, the average inclination angle is preferably 70 ° to 90 °, more preferably 80 ° to 90 °, and most preferably 85 ° to 90 °.

Hereinafter, the composition used in the present invention will be described. The composition can be used for producing the second retardation region of the liquid crystal display device of the present invention. Of course, it goes without saying that the second retardation region of the liquid crystal display device of the present invention may be manufactured from other than this.
(Composition used in the present invention)
The composition used in the present invention is an additive that promotes vertical alignment at the air interface of at least one kind of onium salt, at least one kind of rod-like liquid crystal compound, and an additive that promotes vertical alignment at the alignment film interface. It is preferable to contain at least one agent.
《Onium salt》
In the present invention, it is preferable to contain at least one onium salt. In the present invention, the onium salt contributes to vertically aligning the molecules of the rod-like liquid crystal compound on the alignment film interface side. Examples of the onium salts include onium salts such as ammonium salts, sulfonium salts, and phosphonium salts. A quaternary onium salt is preferable, and a quaternary ammonium salt is more preferable.

  A quaternary ammonium salt is generally a tertiary amine (eg, trimethylamine, triethylamine, tributylamine, triethanolamine, N-methylpyrrolidine, N-methylpiperidine, N, N-dimethylpiperazine, triethylenediamine, N, N , N ′, N′-tetramethylethylenediamine, etc.) or nitrogen-containing heterocycle (pyridine ring, picoline ring, 2,2′-bipyridyl ring, 4,4′-bipyridyl ring, 1,10-phenanthroline ring, quinoline ring, An oxazole ring, a thiazole ring, an N-methylimidazole ring, a pyrazine ring, a tetrazole ring, and the like) are obtained by alkylation (Mentstock reaction), alkenylation, alkynylation, or arylation.

As the quaternary ammonium salt, a quaternary ammonium salt composed of a nitrogen-containing heterocyclic ring is preferable, and a quaternary pyridinium salt is particularly preferable.
More specifically, the quaternary ammonium salt is preferably selected from quaternary pyridinium salts represented by the following general formula (3a) or a general formula (3b) described later.

式（３ａ）中、Ｒ⁸は置換もしくは無置換の、アルキル基、アルケニル基、アルキニル基、アラルキル基、アリール基または複素環基を表し、Ｄは水素結合性基を表し、ｍは１〜３の整数を表し、Ｘ^-はアニオンを表す。

In the formula (3a), R ⁸ represents a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group or heterocyclic group, D represents a hydrogen bonding group, and m represents 1 to 3 X ⁻ represents an anion.

First, the general formula (3a) will be described.
The alkyl group represented by R ⁸ is preferably a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, and more preferably a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms. These may be linear, branched or cyclic. Examples of these are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-hexyl, n-octyl, neopentyl, cyclohexyl, adamantyl. Group and cyclopropyl group.

  Examples of the substituent of the alkyl group include the following. A substituted or unsubstituted alkenyl group having 2 to 18 carbon atoms (preferably 2 to 8 carbon atoms) (for example, a vinyl group); a substitution of 2 to 18 carbon atoms (preferably 2 to 8 carbon atoms) or Unsubstituted alkynyl group (for example, ethynyl group); substituted or unsubstituted aryl group having 6 to 10 carbon atoms (for example, phenyl group, naphthyl group); halogen atom (for example, F, Cl, Br, etc.); carbon A substituted or unsubstituted alkoxy group having 1 to 18 atoms (preferably 1 to 8 carbon atoms) (for example, a methoxy group or an ethoxy group); a substituted or unsubstituted aryloxy group having 6 to 10 carbon atoms (for example, , Phenoxy group, biphenyloxy group, p-methoxyphenoxy group); substituted or unsubstituted alkylthio having 1 to 18 carbon atoms (preferably 1 to 8 carbon atoms) (For example, methylthio group, ethylthio group); substituted or unsubstituted arylthio group having 6 to 10 carbon atoms (for example, phenylthio group); substituted or having 2 to 18 carbon atoms (preferably 2 to 8 carbon atoms) or Unsubstituted acyl group (for example, acetyl group, propionyl group);

  A substituted or unsubstituted alkylsulfonyl group or arylsulfonyl group (for example, methanesulfonyl group, p-toluenesulfonyl group) having 1 to 18 carbon atoms (preferably 1 to 8 carbon atoms); 2 to 18 carbon atoms ( Preferably substituted or unsubstituted acyloxy group having 2 to 8 carbon atoms (for example, acetoxy group, propionyloxy group); substituted or unsubstituted having 2 to 18 carbon atoms (preferably 2 to 8 carbon atoms) Alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group); substituted or unsubstituted aryloxycarbonyl group having 7 to 11 carbon atoms (for example, naphthoxycarbonyl group); unsubstituted amino group, or number of carbon atoms 1-18 (preferably 1-8 carbon atoms) substituted amino groups (eg methylamino , Dimethylamino group, diethylamino group, anilino group, methoxyphenylamino group, chlorophenylamino group, pyridylamino group, methoxycarbonylamino group, n-butoxycarbonylamino group, phenoxycarbonylamino group, methylcarbamoylamino group, ethylthiocarbamoylamino group Phenylcarbamoylamino group, acetylamino group, ethylcarbonylamino group, ethylthiocarbamoylamino group, cyclohexylcarbonylamino group, benzoylamino group, chloroacetylamino group, methylsulfonylamino group);

  A substituted or unsubstituted carbamoyl group having 1 to 18 carbon atoms (preferably 1 to 8 carbon atoms) (for example, unsubstituted carbamoyl group, methylcarbamoyl group, ethylcarbamoyl group, n-butylcarbamoyl group, tert-butyl) A rucarbamoyl group, a dimethylcarbamoyl group, a morpholinocarbamoyl group, a pyrrolidinocarbamoyl group); an unsubstituted sulfamoyl group, or a substituted sulfamoyl group having 1 to 18 carbon atoms (preferably 1 to 8 carbon atoms) (for example, methylsulfayl group) Moyl group, phenylsulfamoyl group); cyano group; nitro group; carboxy group; hydroxyl group; heterocyclic group (for example, oxazole ring, benzoxazole ring, thiazole ring, benzothiazole ring, imidazole ring, benzimidazole ring, indolenine) Ring, pyridine ring, Lysine ring, pyrrolidine ring, morpholine ring, sulfolane ring, furan ring, thiophene ring, pyrazole ring, pyrrole ring, chroman ring, a coumarin ring). The substituent for the alkyl group is particularly preferably an aryloxy group, an arylthio group, an arylsulfonyl group, or an aryloxycarbonyl group.

The alkenyl group represented by R ⁸ is preferably a substituted or unsubstituted alkenyl group having 2 to 18 carbon atoms, more preferably a substituted or unsubstituted alkenyl group having 2 to 8 carbon atoms. A vinyl group, an allyl group, 1-propenyl group, 1,3-butadienyl group, etc. are mentioned.
As the substituent for the alkenyl group, those exemplified as the substituent for the alkyl group are preferable.

The alkynyl group represented by R ⁸ is preferably a substituted or unsubstituted alkynyl group having 2 to 18 carbon atoms, more preferably a substituted or unsubstituted alkynyl group having 2 to 8 carbon atoms. An ethynyl group, 2-propynyl, etc. are mentioned. As the substituent for the alkynyl group, those exemplified as the substituent for the alkyl group are preferable.

The aralkyl group represented by R ⁸ is preferably a substituted or unsubstituted aralkyl group having 7 to 18 carbon atoms, such as a benzyl group, a methylbenzyl group, a biphenylmethyl group, or a naphthylmethyl group. Examples of the substituent for the aralkyl group include those exemplified as the substituent for the alkyl group.

The aryl group represented by R ⁸ is preferably a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and a fluorenyl group. As the substituent for the aryl group, those exemplified as the substituent for the alkyl group are preferable. In addition to these, an alkyl group (for example, a methyl group, an ethyl group, etc.), an alkynyl group, and a benzoyl group are also preferable.

The heterocyclic group represented by R ⁸ is a 5- or 6-membered saturated or unsaturated heterocyclic ring composed of a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom, and examples thereof include oxazole Ring, benzoxazole ring, thiazole ring, benzothiazole ring, imidazole ring, benzimidazole ring, indolenine ring, pyridine ring, piperidine ring, pyrrolidine ring, morpholine ring, sulfolane ring, furan ring, thiophene ring, pyrazole ring, pyrrole ring , Chroman ring, and coumarin ring. The heterocyclic group may be substituted, and as the substituent in that case, those exemplified as the substituent of the alkyl group are preferable. As the heterocyclic group represented by R ⁸ , a benzoxazole ring and a benzothiazole ring are particularly preferable.

R ⁸ is preferably a substituted or unsubstituted alkyl group, aralkyl group, aryl group or heterocyclic group.

  D represents a hydrogen bonding group. Hydrogen bonds exist between electrically negative atoms (eg, O, N, F, Cl) and hydrogen atoms covalently bonded to similarly electronegative atoms. As a theoretical interpretation of hydrogen bonding, for example, H.H. Unneyama and K.M. There are reports in Morokuma, Journal of American Chemical Society, Vol. 99, pp. 1316-1332, 1977. Specific examples of hydrogen bonding include J. N. Examples include Israes Ativiri, Yasuo Kondo, Hiroyuki Oshima, Intermolecular Force and Surface Force, McGraw Hill, 1991, page 98, FIG. Specific examples of hydrogen bonding include, for example, G.I. R. Examples include those described in Desiraju, Angewent Chemistry International Edition England, Vol. 34, p. 2311, 1995.

  Preferred hydrogen bonding groups include mercapto groups, hydroxy groups, amino groups, carbonamido groups, sulfonamido groups, acid amide groups, ureido groups, carbamoyl groups, carboxyl groups, sulfo groups, nitrogen-containing heterocyclic groups (for example, imidazolyl). Group, benzimidazolyl group, pyrazolyl group, pyridyl group, 1,3,5-triazyl group, pyrimidyl group, pyridazyl group, quinolyl group, benzimidazolyl group, benzthiazolyl group, succinimide group, phthalimide group, maleimide group, uracil group, thiouracil Group, barbituric acid group, hydantoin group, maleic hydrazide group, isatin group, uramil group and the like. More preferred hydrogen bonding groups include amino group, carbonamido group, sulfonamido group, ureido group, carbamoyl group, carboxyl group, sulfo group, and pyridyl group, and particularly preferred are amino group, carbamoyl group, A pyridyl group can be mentioned.

The anion represented by X ⁻ may be either an inorganic anion or an organic anion, such as a halogen anion (eg, fluorine ion, chlorine ion, bromine ion, iodine ion), sulfonate ion (eg, methanesulfone). Acid ion, trifluoromethanesulfonic acid ion, methylsulfuric acid ion, p-toluenesulfonic acid ion, p-chlorobenzenesulfonic acid ion, 1,3-benzenedisulfonic acid ion, 1,5-naphthalenedisulfonic acid ion, 2,6-naphthalene Disulfonate ions, etc.), sulfate ions, thiocyanate ions, perchlorate ions, tetrafluoroborate ions, picrate ions, acetate ions, phosphate ions (for example, hexafluorophosphate ions), hydroxide ions, etc. .
X ⁻ is preferably a halogen anion, a sulfonate ion, or a hydroxide ion. X ⁻ need not be a monovalent anion and may be a divalent or higher anion. In such a case, the ratio of the cation to the anion in the compound need not be 1: 1, It is determined.

  In the general formula (3a), m is preferably 1.

  Next, the general formula (3b) will be described.

式（３ｂ）中、Ｒ⁹およびＲ¹⁰は各々置換もしくは無置換の、アルキル基、アルケニル基、アルキニル基、アラルキル基、アリール基または複素環基を表し、Ｘ^-はアニオンを表す。
Ｒ⁹およびＲ¹⁰で各々表される置換もしくは無置換の、アルキル基、アルケニル基、アルキニル基、アラルキル基、アリール基または複素環基は、前記一般式（３ａ）中、Ｒ⁸で表される基と同義であり、その好ましい範囲も同一である。Ｘ^-で表されるアニオンは、前記一般式（３ａ）中、Ｘ^-で表されるアニオンと同義であり、その好ましい範囲も同一である。上述した様に、Ｘ^-は１価のアニオンである必要はなく、２価以上のアニオンであってもよく、かかる場合は、前記化合物中のカチオンとアニオンとの比率も１：２である必要はなく、適宜決定される。

In the formula (3b), R ⁹ and R ¹⁰ each represent a substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group or heterocyclic group, and X ⁻ represents an anion.
The substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group or heterocyclic group represented by R ⁹ and R ¹⁰ respectively is represented by R ⁸ in the general formula (3a). It has the same meaning as the group, and its preferred range is also the same. X ^- anion represented by the In the general formula (3a), X ^- has the same meaning as anion represented by, and the preferable ranges thereof are also the same. As described above, X ⁻ need not be a monovalent anion but may be a divalent or higher anion. In such a case, the ratio of the cation to the anion in the compound should be 1: 2. It is not determined.

  Specific examples of the quaternary pyridinium salt represented by the general formula (3a) or (3b) and other onium salts preferably used in the present invention are shown below, but the onium salts used in the present invention are shown below. It is not limited.

  The preferable content of the onium salt in the composition used in the present invention varies depending on the type, but is usually 0.01 to 10% by mass with respect to the content of the rod-like liquid crystalline compound used in combination. It is preferable that it is 0.05-7 mass%, and it is still more preferable that it is 0.05-5 mass%. Two or more kinds of onium salts may be used. In such a case, the total content of all kinds of onium salts to be used is preferably within the above range.

《Bar-shaped liquid crystalline compound》
The composition used in the present invention contains at least one liquid crystal compound, and preferably contains at least one rod-like liquid crystal compound. The rod-like liquid crystalline compound employed in the present invention can be used as a liquid crystalline compound having positive refractive index anisotropy. The rod-like liquid crystalline compound used in the present invention may be a high molecular compound or a low molecular compound. Further, the rod-like liquid crystalline compound may no longer have liquid crystallinity when it is fixed in the optically anisotropic layer. Preferred examples of the rod-like liquid crystalline compound include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy Substituted phenylpyrimidines, phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles. Not only the above low-molecular liquid crystalline compounds but also high-molecular liquid crystalline compounds can be used. As the liquid crystalline compound, those having a partial structure capable of causing polymerization or crosslinking reaction by actinic rays, electron beams, heat, or the like are suitably used. The number of the partial structures is preferably 1 to 6, more preferably 1 to 3. The rod-like liquid crystalline compound employed in the present invention is preferably a polymerizable rod-like liquid crystalline compound having a polymerizable group in order to fix the alignment state. The polymerizable group is preferably a radically polymerizable unsaturated group or a cationically polymerizable group. Specifically, for example, the polymerizable group described in paragraphs [0064] to [0086] of JP-A-2002-62427, polymerization Liquid crystal compounds.

《Air interface vertical alignment agent》
The composition used in the present invention contains at least one additive that promotes vertical alignment at the air interface of the rod-like liquid crystal compound (hereinafter sometimes referred to as “air interface vertical alignment agent”). Since the rod-like liquid crystalline compound has a property of being tilted and aligned on the air interface side, it is necessary to control the alignment of the liquid crystal compound vertically on the air interface side in order to obtain a uniformly vertically aligned state. For this purpose, the composition contains a compound that is unevenly distributed on the air interface side and acts to vertically align the liquid crystalline compound by its excluded volume effect or electrostatic effect, thereby forming an optically anisotropic layer. Preferably formed.

  As the air interface vertical alignment agent, compounds described in JP-A Nos. 2002-20363 and 2002-129162 can be used. Also, paragraph numbers [0072] to [0075] of Japanese Patent Application Laid-Open No. 2004-53981, paragraph numbers [0071] to [0078] of Japanese Patent Application Laid-Open No. 2004-4688, and paragraphs of Japanese Patent Application Laid-Open No. 2004-139015. The matters described in the numbers [0052] to [0054], [0065] to [0066], and [0092] to [0094] can be appropriately applied to the present invention. Examples of the air interface vertical alignment agent include the following compounds B-1 to B-33 and compounds C-1 to C-45.

The air interface vertical alignment agent includes a fluoro aliphatic group, a carboxyl group (—COOH), a sulfo group (—SO ₃ H), a sulfato group (—OSO ₃ H), a phosphonoxy group {—OP (═O) (OH). ₂ } and a compound containing at least one hydrophilic group selected from the group consisting of salts thereof. The compound having such a structure increases the inclination angle of the director on the air interface side of the rod-like liquid crystal compound, improves the applicability of the composition used in the present invention, and contributes to the reduction of unevenness and play. The compound having at least one of the fluoroaliphatic group and the hydrophilic group (including a high molecular compound and a low molecular compound) may have a polymerizable group. It also contributes to fixing the orientation of the compound.

The air interface vertical alignment agent used in the present invention is a polymer having at least one fluoroaliphatic group and a hydrophilic group (hereinafter sometimes referred to as “fluorine polymer”); or represented by the following general formula (2): It is preferable that it is a compound.
First, the fluorine-based polymer that can be used in the composition used in the present invention will be described.

<< Fluoropolymer >>
The fluoropolymer includes a fluoroaliphatic group, a carboxyl group (—COOH), a sulfo group (—SO ₃ H), a phosphonoxy group {—OP (═O) (OH) ₂ }, and a salt thereof. Those having one or more selected hydrophilic groups are exemplified. The types of polymers are described in “Revised Chemistry of Polymer Synthesis” (Takayuki Otsu, published by Kagaku Dojin Co., 1968), pages 1-4, for example, polyolefins, polyesters, polyamides, polyimides. , Polyurethanes, polycarbonates, polysulfones, polycarbonates, polyethers, polyacetals, polyketones, polyphenylene oxides, polyphenylene sulfides, polyarylates, PTFEs, polyvinylidene fluorides, cellulose derivatives, etc. It is done. The fluoropolymer is preferably a polyolefin.

  The fluorine-based polymer is a polymer having a fluoroaliphatic group in the side chain. The fluoroaliphatic group preferably has 1 to 12 carbon atoms, and more preferably 6 to 10 carbon atoms. The aliphatic group may be linear or cyclic, and when it is linear, it may be linear or branched. Among these, a linear fluoroaliphatic group having 6 to 10 carbon atoms is preferable. The degree of substitution with fluorine atoms is not particularly limited, but 50% or more of hydrogen atoms in the aliphatic group are preferably substituted with fluorine atoms, and more preferably 60% or more are substituted. The fluoroaliphatic group is contained in a side chain bonded to the polymer main chain via an ester bond, an amide bond, an imide bond, a urethane bond, a urea bond, an ether bond, a thioether bond, an aromatic ring, or the like. One of the fluoroaliphatic groups is derived from a fluoroaliphatic compound produced by a telomerization method (also referred to as a telomer method) or an oligomerization method (also referred to as an oligomer method). Regarding the production method of these fluoroaliphatic compounds, for example, “Synthesis and Function of Fluorine Compounds” (Supervision: Nobuo Ishikawa, Issue: CMC Co., 1987), “Chemistry of Organic Fluorines Compounds”. II "(Monograph 187, Ed by Milos Hudricky and Attila E. Pavlath, American Chemical Society 1995). The telomerization method is a method of synthesizing a telomer by radical polymerization of a fluorine-containing vinyl compound such as tetrafluoroethylene using an alkyl halide having a large chain transfer constant such as iodide as a telogen (example in Scheme-1). showed that).

  The obtained terminal iodinated telomer is usually subjected to appropriate terminal chemical modification such as [Scheme 2], and led to a fluoroaliphatic compound. These compounds are further converted into a desired monomer structure as necessary, and used for the production of a fluoroaliphatic group-containing polymer.

  Specific examples of the fluoroaliphatic group-containing monomer that can be used in the production of the fluorine-based polymer that can be used in the present invention are listed below, but the present invention is not limited to the following specific examples.

  The fluoropolymer is preferably selected from a copolymer having a repeating unit derived from a fluoroaliphatic group-containing monomer and a repeating unit containing a hydrophilic group represented by the following general formula (1). .

In the general formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent. Q represents a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a phosphonoxy group {—OP (═O) (OH) ₂ } or a salt thereof. L represents an arbitrary group selected from the following linking group group, or a divalent linking group formed by combining two or more thereof.
(Linked group group)
Single bond, —O—, —CO—, —NR ⁴ — (R ⁴ represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group), —S—, —SO ₂ —, —P (═O) (OR ⁵ ) — (R ⁵ represents an alkyl group, an aryl group, or an aralkyl group), an alkylene group, and an arylene group (the combination of an arylene group includes a condensed ring)

The substituent groups R ¹ , R ^2, and R ³ include the following substituent group Y.
(Substituent group Y)
An alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, a tert- Butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group and the like), alkenyl group (preferably having 2 to 20 carbon atoms, more preferably carbon atom) An alkenyl group having 2 to 12, particularly preferably 2 to 8 carbon atoms, and examples thereof include a vinyl group, an allyl group, a 2-butenyl group, and a 3-pentenyl group, and an alkynyl group (preferably a carbon atom). An alkynyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms. Gil group, 3-pentynyl group and the like), aryl group (preferably 6-30 carbon atoms, more preferably 6-20 carbon atoms, particularly preferably 6-12 carbon atoms aryl group, For example, a phenyl group, a p-methylphenyl group, a naphthyl group, etc. are mentioned), an aralkyl group (preferably 7-30 carbon atoms, more preferably 7-20 carbon atoms, particularly preferably 7-12 carbon atoms). An aralkyl group of, for example, a benzyl group, a phenethyl group, or a 3-phenylpropyl group), a substituted or unsubstituted amino group (preferably having 0 to 20 carbon atoms, more preferably 0 to 0 carbon atoms). 10, particularly preferably an amino group having 0 to 6 carbon atoms, such as an unsubstituted amino group, a methylamino group, a dimethylamino group, diethylamino Groups, such as anilino group),

An alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 10 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, and a butoxy group. An alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, and particularly preferably 2 to 10 carbon atoms, such as a methoxycarbonyl group and an ethoxycarbonyl group). And an acyloxy group (preferably an acyloxy group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include an acetoxy group and a benzoyloxy group. ), An acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 2 carbon atoms). 6, particularly preferably an acylamino group having 2 to 10 carbon atoms, such as an acetylamino group and a benzoylamino group, an alkoxycarbonylamino group (preferably having 2 to 20 carbon atoms, more preferably a carbon atom) An alkoxycarbonylamino group having 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as a methoxycarbonylamino group, and an aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms; An aryloxycarbonylamino group having 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms is preferable, and examples thereof include a phenyloxycarbonylamino group, and a sulfonylamino group (preferably having 1 carbon atom). To 20, more preferably 1 to 16 carbon atoms, particularly preferred Or a sulfonylamino group having 1 to 12 carbon atoms, such as a methanesulfonylamino group or a benzenesulfonylamino group), a sulfamoyl group (preferably having a carbon atom number of 0 to 20, more preferably a carbon atom number). 0 to 16, particularly preferably a sulfamoyl group having 0 to 12 carbon atoms, and examples thereof include a sulfamoyl group, a methylsulfamoyl group, a dimethylsulfamoyl group, and a phenylsulfamoyl group), a carbamoyl group ( Preferably it is a carbamoyl group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as an unsubstituted carbamoyl group, a methylcarbamoyl group, a diethylcarbamoyl group, Phenylcarbamoyl group, etc.),

An alkylthio group (preferably an alkylthio group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include a methylthio group and an ethylthio group). An arylthio group (preferably an arylthio group having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as a phenylthio group), a sulfonyl group ( Preferably they are C1-C20, More preferably, it is C1-C16, Most preferably, it is C1-C12 sulfonyl group, for example, a mesyl group, a tosyl group etc. are mentioned), a sulfinyl group ( Preferably, it is a sulfo having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms. Nyl group, for example, methanesulfinyl group, benzenesulfinyl group, etc.), ureido group (preferably 1-20 carbon atoms, more preferably 1-16 carbon atoms, particularly preferably 1-1 carbon atoms). 12 ureido groups, for example, an unsubstituted ureido group, a methylureido group, a phenylureido group and the like, and a phosphoric acid amide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 1 carbon atom). 16, particularly preferably a phosphoric acid amide group having 1 to 12 carbon atoms, such as a diethylphosphoric acid amide group and a phenylphosphoric acid amide group, a hydroxy group, a mercapto group, a halogen atom (for example, a fluorine atom) , Chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group A sulfino group, a hydrazino group, an imino group, a heterocyclic group (preferably a heterocyclic group having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms such as a nitrogen atom, an oxygen atom, a sulfur atom, etc. For example, an imidazolyl group, a pyridyl group, a quinolyl group, a furyl group, a piperidyl group, a morpholino group, a benzoxazolyl group, a benzimidazolyl group, a benzthiazolyl group), a silyl group (preferably A silyl group having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms, and examples thereof include a trimethylsilyl group and a triphenylsilyl group) It is. These substituents may be further substituted with these substituents. Moreover, when it has two or more substituents, they may be the same or different. If possible, they may be bonded to each other to form a ring.

R ¹ , R ² and R ³ are each independently a hydrogen atom, an alkyl group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), or a group represented by -LQ described later. And more preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a chlorine atom, or a group represented by -LQ, and a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. It is particularly preferable that a hydrogen atom or an alkyl group having 1 to 2 carbon atoms is most preferable. Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, n-butyl group, sec-butyl group and the like. The alkyl group may have a suitable substituent. Examples of the substituent include a halogen atom, aryl group, heterocyclic group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, acyl group, hydroxyl group, acyloxy group, amino group, alkoxycarbonyl group, acylamino group, oxycarbonyl Group, carbamoyl group, sulfonyl group, sulfamoyl group, sulfonamido group, sulfolyl group, carboxyl group and the like. In addition, the carbon atom number of the above alkyl group does not include the carbon atom of the substituent. The same applies to the number of carbon atoms of other groups.

L represents a divalent linking group selected from the above linking group group, or a divalent linking group formed by combining two or more thereof. In the linking group group, R ^{4 in} —NR ⁴ — represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and preferably a hydrogen atom or an alkyl group. R ⁵ in —PO (OR ⁵ ) — represents an alkyl group, an aryl group or an aralkyl group, and preferably an alkyl group. The preferred range of the number of carbon atoms when R ⁴ and R ⁵ represent an alkyl group, an aryl group or an aralkyl group is the same as that described in “Substituent group Y”. L preferably contains a single bond, —O—, —CO—, —NR ⁴ —, —S—, —SO ₂ —, an alkylene group or an arylene group, and —CO—, —O—, —NR ⁴ -, and more preferably those containing an alkylene group or an arylene group. When L contains an alkylene group, the number of carbon atoms of the alkylene group is preferably 1 to 10, more preferably 1 to 8, and particularly preferably 1 to 6. Specific examples of particularly preferable alkylene groups include a methylene group, an ethylene group, a trimethylene group, a tetrabutylene group, and a hexamethylene group. When L contains an arylene group, the number of carbon atoms of the arylene group is preferably 6 to 24, more preferably 6 to 18, and particularly preferably 6 to 12. Specific examples of particularly preferred arylene groups include phenylene groups and naphthalene groups. When L contains a divalent linking group obtained by combining an alkylene group and an arylene group (that is, an aralkylene group), the number of carbon atoms of the aralkylene group is preferably 7 to 34, more preferably 7 to 26, and particularly preferably. Is 7-16. Specific examples of particularly preferred aralkylene groups include a phenylenemethylene group, a phenyleneethylene group, and a methylenephenylene group. The group listed as L may have a suitable substituent. Examples of such a substituent include the same substituents as those exemplified as the substituent group Y.

  Although the specific structure of L is illustrated below, this invention is not limited to these specific examples.

  In the formula (1), Q is a carboxyl group or a carboxyl group salt (for example, lithium salt, sodium salt, potassium salt, ammonium salt (for example, ammonium, tetramethylammonium, trimethyl-2-hydroxyethylammonium, tetrabutylammonium). , Trimethylbenzylammonium, dimethylphenylammonium, etc.), pyridinium salts, etc.), sulfo group, sulfo group salt (examples of cations forming the salt are the same as those described in the above carboxyl group), phosphonoxy group, phosphonoxy group salt (Examples of the cation forming the salt are the same as those described for the carboxyl group). A carboxyl group, a sulfo group, and a phospho group are more preferable, and a carboxyl group or a sulfo group is particularly preferable.

  The fluoropolymer may contain one type of repeating unit represented by the general formula (1) or two or more types. Moreover, the said fluorine-type polymer may have 1 type (s) or 2 or more types of repeating units other than said each repeating unit. The other repeating units are not particularly limited, and preferred examples thereof include repeating units derived from ordinary radical polymerizable monomers. Hereinafter, specific examples of monomers for deriving other repeating units will be given. The fluoropolymer may contain a repeating unit derived from one or two or more monomers selected from the following monomer group.

Monomer group (1) Alkenes ethylene, propylene, 1-butene, isobutene, 1-hexene, 1-dodecene, 1-octadecene, 1-eicosene, hexafluoropropene, vinylidene fluoride, chlorotrifluoroethylene, 3, 3, 3-trifluoropropylene, tetrafluoroethylene, vinyl chloride, vinylidene chloride, etc .;
(2) Dienes 1,3-butadiene, isoprene, 1,3-pentadiene, 2-ethyl-1,3-butadiene, 2-n-propyl-1,3-butadiene, 2,3-dimethyl-1,3 -Butadiene, 2-methyl-1,3-pentadiene, 1-phenyl-1,3-butadiene, 1-α-naphthyl-1,3-butadiene, 1-β-naphthyl-1,3-butadiene, 2-chloro -1,3-butadiene, 1-bromo-1,3-butadiene, 1-chlorobutadiene, 2-fluoro-1,3-butadiene, 2,3-dichloro-1,3-butadiene, 1,1,2- Trichloro-1,3-butadiene and 2-cyano-1,3-butadiene, 1,4-divinylcyclohexane and the like;

(3) Derivatives of α, β-unsaturated carboxylic acid (3a) Alkyl acrylates Methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate , Amyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, tert-octyl acrylate, dodecyl acrylate, phenyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, 2-bromoethyl acrylate, 4-chlorobutyl acrylate, 2-cyanoethyl acrylate, 2-acetoxyethyl acrylate, methoxybenzyl Chryrate, 2-chlorocyclohexyl acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, 2-methoxyethyl acrylate, ω-methoxypolyethylene glycol acrylate (polyoxyethylene added moles: n = 2-100), 3-methoxy Butyl acrylate, 2-ethoxyethyl acrylate, 2-butoxyethyl acrylate, 2- (2-butoxyethoxy) ethyl acrylate, 1-bromo-2-methoxyethyl acrylate, 1,1-dichloro-2-ethoxyethyl acrylate, glycidyl acrylate Such);

(3b) Alkyl methacrylates Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, amyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2 -Ethylhexyl methacrylate, n-octyl methacrylate, stearyl methacrylate, benzyl methacrylate, phenyl methacrylate, allyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, cresyl methacrylate, naphthyl methacrylate, 2-methoxyethyl methacrylate, 3-methoxybutyl methacrylate, ω Methoxy polyethylene glycol methacrylate (number of added polyoxyethylene: n = 2-100), 2-acetoxyethyl methacrylate, 2-ethoxyethyl methacrylate, 2-butoxyethyl methacrylate, 2- (2-butoxyethoxy) ethyl methacrylate Glycidyl methacrylate, 3-trimethoxysilylpropyl methacrylate, allyl methacrylate, 2-isocyanatoethyl methacrylate, etc .;

(3c) Diesters of unsaturated polycarboxylic acids Dimethyl maleate, dibutyl maleate, dimethyl itaconate, dibutyl taconate, dibutyl crotonate, dihexyl crotonate, diethyl fumarate, dimethyl fumarate, etc .;

(3d) Amides of α, β-unsaturated carboxylic acids N, N-dimethylacrylamide, N, N-diethylacrylamide, Nn-propylacrylamide, N-tertbutylacrylamide, N-tertoctylmethacrylamide, N- Cyclohexylacrylamide, N-phenylacrylamide, N- (2-acetoacetoxyethyl) acrylamide, N-benzylacrylamide, N-acryloylmorpholine, diacetone acrylamide, N-methylmaleimide and the like;

(4) Unsaturated nitriles Acrylonitrile, methacrylonitrile, etc .;
(5) Styrene and its derivatives Styrene, vinyl toluene, ethyl styrene, p-tert butyl styrene, methyl p-vinyl benzoate, α-methyl styrene, p-chloromethyl styrene, vinyl naphthalene, p-methoxy styrene, p-hydroxy Methyl styrene, p-acetoxy styrene, etc .;
(6) Vinyl esters Vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl benzoate, vinyl salicylate, vinyl chloroacetate, vinyl methoxyacetate, vinyl vinyl acetate, etc .;

(7) Vinyl ethers Methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-octyl vinyl ether, n-dodecyl Vinyl ether, n-eicosyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, fluorobutyl vinyl ether, fluorobutoxyethyl vinyl ether, etc .; and (8) other polymerizable monomers N-vinyl pyrrolidone, methyl vinyl ketone, phenyl vinyl ketone, Methoxyethyl vinyl ketone, 2-vinyl oxazoline, 2-isopropenyl oxazoline .

  In the fluoropolymer, the amount of the fluoroaliphatic group-containing monomer is preferably 5% by mass or more, more preferably 10% by mass or more, and more preferably 30% by mass or more of the total amount of constituent monomers of the polymer. Is more preferable. In the fluoropolymer, the amount of the repeating unit represented by the general formula (1) is preferably 0.5% by mass or more, and 1 to 20% by mass of the total amount of the constituent monomers of the fluoropolymer. Is more preferable, and it is further more preferable that it is 1-10 mass%. Since the above-mentioned mass percentage is likely to vary in the preferred range depending on the molecular weight of the monomer used, the content of the repeating unit represented by the general formula (1) is expressed by the number of moles of the functional group per unit mass of the polymer. Can be defined accurately. When this notation is used, the preferable amount of the hydrophilic group (Q in the formula (1)) contained in the fluoropolymer is 0.1 mmol / g to 10 mmol / g, and the more preferable amount is 0. .2 mmol / g to 8 mmol / g.

  The fluorine-based polymer used in the present invention preferably has a mass average molecular weight of 1,000,000 or less, more preferably 500,000 or less, still more preferably 100,000 or less, 000 to 50,000 is most preferred. The mass average molecular weight can be measured as a value in terms of polystyrene (PS) using gel permeation chromatography (GPC).

  The manufacturing method of the said fluorine-type polymer is not specifically limited, It can manufacture by a well-known and usual method. For example, it can be produced by adding a general-purpose radical polymerization initiator to an organic solvent containing the above-mentioned monomer having a fluoroaliphatic group, a monomer having a hydrogen bonding group, and the like, and polymerizing it. Further, in some cases, other addition-polymerizable unsaturated compounds can be further added and produced by the same method as described above. Depending on the polymerizability of each monomer, a dropping polymerization method in which a monomer and an initiator are added dropwise to a reaction vessel is also effective for obtaining a polymer having a uniform composition. For example, a polymerization method such as cationic polymerization, radical polymerization, or anionic polymerization using a vinyl group can be employed, and among these, radical polymerization is particularly preferable because it can be used for general purposes. As the polymerization initiator for radical polymerization, known compounds such as radical thermal polymerization initiators and radical photopolymerization initiators can be used, and it is particularly preferable to use radical thermal polymerization initiators. Here, the radical thermal polymerization initiator is, for example, a compound that generates radicals by heating to a decomposition temperature or higher. Examples of such radical thermal polymerization initiators include diacyl peroxide (acetyl peroxide, benzoyl peroxide, etc.), ketone peroxide (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), hydroperoxide (hydrogen peroxide, tert. -Butyl hydroxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxyesters (tert-butyl peroxyacetate, tert) -Butyl peroxypivalate, etc.), azo compounds (azobisisobutyronitrile, azobisisovaleronitrile, etc.), persulfates (ammonium persulfate, sodium persulfate) And potassium persulfate) and the like. Such radical thermal polymerization initiators can be used singly or in combination of two or more.

  The radical polymerization method is not particularly limited, and an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, a solution polymerization method, and the like can be adopted. The solution polymerization, which is a typical radical polymerization method, will be described more specifically. The outlines of other polymerization methods are the same, and details thereof are described, for example, in “Polymer Science Experimental Method” edited by Polymer Society (Tokyo Kagaku Dojin, 1981).

  An organic solvent is used for solution polymerization. These organic solvents can be arbitrarily selected as long as the objects and effects of the present invention are not impaired. These organic solvents are usually organic compounds having boiling points under atmospheric pressure in the range of 50 to 200 ° C., and organic compounds that uniformly dissolve each component are preferred. Examples of preferred organic solvents include alcohols such as isopropanol and butanol; ethers such as dibutyl ether, ethylene glycol dimethyl ether, tetrahydrofuran and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ethyl acetate and acetic acid And esters such as butyl, amyl acetate, and γ-butyrolactone; and aromatic hydrocarbons such as benzene, toluene, and xylene. These organic solvents can be used alone or in combination of two or more. Furthermore, a water-mixed organic solvent in which water is used in combination with the above organic solvent is also applicable from the viewpoint of the solubility of the monomer and the polymer to be produced.

  Also, the solution polymerization conditions are not particularly limited, but for example, it is preferable to heat within a temperature range of 50 to 200 ° C. for 10 minutes to 30 hours. Furthermore, in order not to deactivate the generated radicals, it is preferable to perform an inert gas purge not only during solution polymerization but also before the start of solution polymerization. Usually, nitrogen gas is suitably used as the inert gas.

  In order to obtain the fluoropolymer in a preferable molecular weight range, a radical polymerization method using a chain transfer agent is particularly effective. As chain transfer agents, mercaptans (for example, octyl mercaptan, decyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan, octadecyl mercaptan, thiophenol, p-nonylthiophenol, etc.), polyhalogenated alkyls (for example, carbon tetrachloride, chloroform, etc.) , 1,1,1-trichloroethane, 1,1,1-tribromooctane, etc.) and low-activity monomers (α-methylstyrene, α-methylstyrene dimer, etc.) can be used, preferably carbon It is a mercaptan having 4 to 16 atoms. The amount of these chain transfer agents used is remarkably influenced by the activity of the chain transfer agent, the combination of monomers, the polymerization conditions, etc., and needs to be precisely controlled, but is preferably 0 with respect to the total number of moles of monomers used. It is about 0.01 mol% to 50 mol%, more preferably 0.05 mol% to 30 mol%, and still more preferably 0.08 mol% to 25 mol%. These chain transfer agents may be present in the system simultaneously with the target monomer whose degree of polymerization is to be controlled in the polymerization process, and the addition method is not particularly limited. It may be added after being dissolved in the monomer, or may be added separately from the monomer.

  As described above, the fluoropolymer preferably has a polymerizable group as a substituent in order to fix the alignment state of the molecules of the rod-like liquid crystalline compound.

  Specific examples of the fluoroaliphatic group-containing copolymer preferably used in the present invention as the fluorine-based polymer are shown below, but the present invention is not limited to these specific examples. Here, the numerical values (numerical values such as a, b, c, and d) in the formula are mass percentages indicating the composition ratio of each monomer, and Mw is a mass average molecular weight in terms of PS measured by GPC.

  The preferred range of the content of the fluoropolymer in the composition used in the present invention varies depending on its use, but when used for forming the optically anisotropic layer, the composition (except for the solvent in the case of a coating solution) is excluded. The composition is preferably 0.005 to 8% by mass, more preferably 0.01 to 5% by mass, and still more preferably 0.05 to 1% by mass. It is more effective when the addition amount of the fluorine-based polymer is 0.005% by mass or more, and when it is 8% by mass or less, the coating film cannot be sufficiently dried, or the performance as an optical film ( For example, it is possible to more effectively prevent adverse effects on retardation uniformity and the like.

Next, the fluorine-containing compound represented by the general formula (2) will be described.
<< Fluorine-containing compound represented by formula (2) >>
General formula (2)
(R ⁰ ) _mo −L ⁰ − (W) _no
In the formula, R ⁰ represents an alkyl group, an alkyl group having a CF ₃ group at the terminal, or an alkyl group having a CF ₂ H group at the terminal, and mo represents an integer of 1 or more. A plurality of R ⁰ may be the same or different, but at least one represents an alkyl group having a CF ₃ group or a CF ₂ H group at the terminal.
L ⁰ represents a (mo + no) -valent linking group, W represents a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a sulfato group (—OSO ₃ H) or a salt thereof, or A phosphonoxy group {—OP (═O) (OH) ₂ } or a salt thereof is preferable.
no represents an integer of 1 or more.

In formula (2), the alkyl group represented by R ⁰ is a substituted or unsubstituted alkyl group, which may be linear or branched, and preferably has 1 to 20 carbon atoms. It is an alkyl group, More preferably, it is a 4-16 alkyl group, Most preferably, it is a 6-16 alkyl group. As the substituent, any of the substituents exemplified as the substituent group D described later can be applied.

The alkyl group having a CF ₃ group at the terminal represented by R ⁰ preferably has 1 to 20 carbon atoms, more preferably 4 to 16, and particularly preferably 4 to 8. The alkyl group having a CF ₃ group at the terminal is an alkyl group in which some or all of the hydrogen atoms contained in the alkyl group are substituted with fluorine atoms. 50% or more of the hydrogen atoms in the alkyl group are preferably substituted with fluorine atoms, more preferably 60% or more are substituted, and particularly preferably 70% or more are substituted. The remaining hydrogen atoms may be further substituted with the substituents exemplified as the substituent group D described later. The alkyl group having a CF ₂ H group at the terminal represented by R ⁰ preferably has 1 to 20 carbon atoms, more preferably 4 to 16 and particularly preferably 4 to 8. The alkyl group having a CF ₂ H group at the terminal is an alkyl group in which some or all of the hydrogen atoms contained in the alkyl group are substituted with fluorine atoms. 50% or more of the hydrogen atoms in the alkyl group are preferably substituted with fluorine atoms, more preferably 60% or more are substituted, and particularly preferably 70% or more are substituted. The remaining hydrogen atoms may be further substituted with the substituents exemplified as the substituent group D described later. Examples of an alkyl group having a CF ₃ group at the terminal represented by R ⁰ or an alkyl group having a CF ₂ H group at the terminal are shown below.

R1: n-C ₈ F _{17-
R2: n-C 6 F 13} -
_{R3: n-C 4 F 9} -
_{R4: n-C 8 F 17} - (CH 2) 2 -
_{R5: n-C 6 F 13} - (CH 2) 2 -
_{R6: n-C 4 F 9} - (CH 2) 2 -
_{R7: H- (CF 2) 8} -
_{R8: H- (CF 2) 6} -
_{R9: H- (CF 2) 4} -
_{R10: H- (CF 2) 8} - (CH 2) -
R11: H— (CF ₂ ) ₆ — (CH ₂ ) —
_{R12: H- (CF 2) 4} - (CH 2) -

In the formula (2), a (mo + no) -valent linking group represented by L ⁰ is an alkylene group, an alkenylene group, an aromatic group, a heterocyclic group, —CO—, or —NR— (R has 1 carbon atom) A linking group obtained by combining at least two groups selected from the group consisting of —O—, —S—, —SO— and SO ₂ —.

In the formula (2), W represents a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a sulfato group (—OSO ₃ H) or a salt thereof, or a phosphonoxy group {—OP (= O) (OH) ₂ } or a salt thereof. The preferable range of W is the same as Q in the general formula (1).

  Among the fluorine-containing compounds represented by the general formula (2), a compound represented by the following general formula (2a) or a general formula (2b) described later is preferable.

In the general formula (2a), R ⁵ and R ⁶ are each alkyl groups, terminal alkyl groups having CF ₃ group or a terminal, represents an alkyl group having a CF ₂ H group, an alkyl R ⁵ and R ⁶ are simultaneously It is not a group. W ¹ and W ² are each a hydrogen atom, a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a sulfato group (—OSO ₃ H) or a salt thereof, a phosphonoxy group {—OP ( ═O) (OH) ₂ } or a salt thereof, or an alkyl group, an alkoxy group or an alkylamino group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent, wherein W ¹ and W ² are simultaneously It is not a hydrogen atom.

R ⁵ and R ⁶ have the same meaning as R ⁰ in the general formula (2), and their preferred ranges are also the same. Carboxyl group (—COOH) or a salt thereof represented by W ¹ and W ² , sulfo group (—SO ₃ H) or a salt thereof, sulfato group (—OSO ₃ H) or a salt thereof, phosphonoxy group {—OP (= O) (OH) ₂ } or a salt thereof is synonymous with W in the general formula (2), and its preferred range is also the same. The alkyl group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent represented by W ¹ and W ² may be linear or branched, and preferably has carbon atoms. 1 to 20 alkyl groups, more preferably 1 to 8 alkyl groups, and particularly preferably 1 to 3 alkyl groups. The alkyl group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as the substituent may have at least one carboxyl group, sulfo group, sulfato group or phosphonoxy group. The group and the phosphonoxy group are synonymous with the carboxyl group, the sulfo group, the sulfato group, and the phosphonoxy group represented by W in the general formula (2), and the preferred range is also the same. The alkyl group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as the substituent may be substituted with a substituent other than this, and the substituent is exemplified as the substituent group D described later. Either of these can be applied. The alkoxy group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent represented by W ¹ and W ² may be linear or branched, and preferably has carbon atoms. 1 to 20 alkoxy groups, more preferably 1 to 8 alkoxy groups, and particularly preferably 1 to 4 alkoxy groups. The alkoxy group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as the substituent only needs to have at least one carboxyl group, sulfo group, sulfato group or phosphonoxy group. The group and the phosphonoxy group are synonymous with the carboxyl group, the sulfo group, the sulfato group, and the phosphonoxy group represented by W in the general formula (2), and the preferred range is also the same. The alkoxy group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group may be substituted with a substituent other than this, and the substituent is any of the substituents exemplified as Substituent Group D described later. Can be applied. The alkylamino group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent represented by W ¹ and W ² may be linear or branched, preferably a carbon atom It is an alkylamino group having a number of 1 to 20, more preferably an alkylamino group of 1 to 8, and particularly preferably an alkylamino group of 1 to 4. The alkylamino group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group may have at least one carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group, such as a carboxyl group, a sulfo group, a sulfato group, and The phosphonoxy group is synonymous with the carboxyl group, sulfo group, sulfato group and phosphonoxy group represented by W in the general formula (2), and the preferred range is also the same. The alkylamino group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group may be substituted with other substituents, and any of the substituents exemplified as Substituent Group D described later can be used as the substituent. Can apply.

W ¹ and W ² are particularly preferably each a hydrogen atom or (CH ₂ ) _n1 SO ₃ M (n1 represents 0 or 1). M represents a cation, but M may not be present when the charge is 0 in the molecule. As cations represented by M, for example, protonium ions, alkali metal ions (lithium ions, sodium ions, potassium ions, etc.), alkaline earth metal ions (barium ions, calcium ions, etc.), ammonium ions and the like are preferably applied. . Of these, proton ions, lithium ions, sodium ions, potassium ions, and ammonium ions are particularly preferable.

Next, the following general formula (2b) will be described.
General formula (2b)
(R ⁷ -L ^1- ) _m2 (Ar ¹ ) -W ³
In the general formula (2b), R ⁷ represents an alkyl group, an alkyl group having a CF ₃ group at the terminal, or an alkyl group having a CF ₂ H group at the terminal, m2 represents an integer of 1 or more, and a plurality of R ⁷ may be the same or different, but at least one represents an alkyl group having a CF ₃ group or a CF ₂ H group at the terminal. L ¹ is an alkylene group, an aromatic group, —CO—, —NR— (R is an alkyl group having 1 to 5 carbon atoms or a hydrogen atom), —O—, —S—, —SO—, —SO. _It represents a divalent linking group selected from the group consisting of _2- and combinations thereof, and a plurality of L ¹ may be the same or different. Ar ¹ represents an aromatic hydrocarbon ring or an aromatic heterocycle, W ³ represents a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a sulfato group (—OSO ₃ H) or A salt thereof, a phosphonoxy group {—OP (═O) (OH) ₂ } or a salt thereof, or an alkyl group, an alkoxy group, or an alkylamino group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group as a substituent. .

The aromatic hydrocarbon ring represented by Ar ¹ is preferably an aromatic hydrocarbon ring having 6 to 12 carbon atoms. The aromatic heterocycle represented by Ar ¹ is preferably an aromatic heterocycle having at least one of a nitrogen atom, an oxygen atom and a sulfur atom and a carbon atom as a ring constituent atom, such as a pyridine ring, A thiophene ring, a furan ring, a pyrimidine ring and the like are preferable. Ar ¹ is preferably an aromatic hydrocarbon ring, more preferably a benzene ring or a naphthalene ring, and even more preferably a benzene ring.

R ⁷ has the same meaning as R ⁰ in formula (2), and its preferred range is also the same. L ¹ is preferably an alkylene group having 1 to 12 carbon atoms, an aromatic group having 6 to 12 carbon atoms, —CO—, —NR—, —O—, —S—, —SO—, —SO _2. -Represents a linking group having a total carbon number of 0 to 40 and a combination thereof, particularly preferably an alkylene group having 1 to 8 carbon atoms, a phenyl group, -CO-, -NR-, -O-, -S. A linking group having 0 to 20 carbon atoms in total, consisting of —, —SO ₂ — and a combination thereof. Carboxyl group represented by W ³ (—COOH) or a salt thereof, sulfo group (—SO ₃ H) or a salt thereof, sulfato group (—OSO ₃ H) or a salt thereof, phosphonoxy group {—OP (═O) ( OH) ₂ } or a salt thereof, or an alkyl group, an alkoxy group, or an alkylamino group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group as a substituent, as W ¹ and W ² in the general formula (2a). Carboxyl group (—COOH) or a salt thereof, sulfo group (—SO ₃ H) or a salt thereof, sulfato group (—OSO ₃ H) or a salt thereof, phosphonoxy group {—OP (═O) (OH) ₂ } Or a salt thereof, or an alkyl group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent, Alkoxy group or has the same meaning as the alkylamino group and the preferable scope thereof is also the same.

W ³ is preferably a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, or a carboxyl group (—COOH) or a salt thereof or a sulfo group (—SO ₃ H) as a substituent. Or an alkylamino group having a salt thereof, particularly preferably SO ₃ M or CO ₂ M. M represents a cation, but M may not be present when the charge is 0 in the molecule. As cations represented by M, for example, protonium ions, alkali metal ions (lithium ions, sodium ions, potassium ions, etc.), alkaline earth metal ions (barium ions, calcium ions, etc.), ammonium ions and the like are preferably applied. . Of these, proton ions, lithium ions, sodium ions, potassium ions, and ammonium ions are particularly preferable.

  In the present specification, the substituent group D includes an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms. , Methyl group, ethyl group, isopropyl group, tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (preferably An alkenyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, such as a vinyl group, an allyl group, a 2-butenyl group, and a 3-pentenyl group. An alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms). A alkynyl group, for example, a propargyl group, a 3-pentynyl group, and the like; an aryl group (preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 6 carbon atoms). 12 aryl groups such as a phenyl group, a p-methylphenyl group, and a naphthyl group, and a substituted or unsubstituted amino group (preferably having 0 to 20 carbon atoms, more preferably 0 carbon atoms). -10, particularly preferably an amino group having 0 to 6 carbon atoms, such as an unsubstituted amino group, a methylamino group, a dimethylamino group, a diethylamino group, a dibenzylamino group).

An alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, and a butoxy group. An aryloxy group (preferably an aryloxy group having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as a phenyloxy group, 2- A naphthyloxy group, etc.), an acyl group (preferably 1-20 carbon atoms, more preferably 1-16 carbon atoms, particularly preferably an acyl group having 1-12 carbon atoms, such as an acetyl group, Benzoyl group, formyl group, pivaloyl group and the like), alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, more preferably An alkoxycarbonyl group having 2 to 16 elementary atoms, particularly preferably 2 to 12 carbon atoms, such as a methoxycarbonyl group and an ethoxycarbonyl group, and an aryloxycarbonyl group (preferably having 7 to 7 carbon atoms). 20, more preferably an aryloxycarbonyl group having 7 to 16 carbon atoms, particularly preferably 7 to 10 carbon atoms, such as a phenyloxycarbonyl group), an acyloxy group (preferably having 2 carbon atoms) To 20, more preferably an acyloxy group having 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include an acetoxy group and a benzoyloxy group).

Acylamino group (preferably an acylamino group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include an acetylamino group and a benzoylamino group) An alkoxycarbonylamino group (preferably an alkoxycarbonylamino group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as a methoxycarbonylamino group) An aryloxycarbonylamino group (preferably an aryloxycarbonylamino group having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, and particularly preferably 7 to 12 carbon atoms). Oxycarbonylamino group), sulfonylamino group Preferably, it is a sulfonylamino group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms, and examples thereof include a methanesulfonylamino group and a benzenesulfonylamino group. ), A sulfamoyl group (preferably a sulfamoyl group having 0 to 20 carbon atoms, more preferably 0 to 16 carbon atoms, particularly preferably 0 to 12 carbon atoms, such as a sulfamoyl group, a methylsulfamoyl group, Dimethylsulfamoyl group, phenylsulfamoyl group and the like), carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms). Groups such as unsubstituted carbamoyl, methylcarbamoyl, Bamoiru group, phenylcarbamoyl group),

An alkylthio group (preferably an alkylthio group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include a methylthio group and an ethylthio group). An arylthio group (preferably an arylthio group having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as a phenylthio group), a sulfonyl group ( Preferably they are C1-C20, More preferably, it is C1-C16, Most preferably, it is C1-C12 sulfonyl group, for example, a mesyl group, a tosyl group etc. are mentioned), a sulfinyl group ( Preferably, it is a sulfo having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms. Nyl group, for example, methanesulfinyl group, benzenesulfinyl group, etc.), ureido group (preferably 1-20 carbon atoms, more preferably 1-16 carbon atoms, particularly preferably 1-1 carbon atoms). 12 ureido groups, for example, an unsubstituted ureido group, a methylureido group, a phenylureido group and the like, and a phosphoric acid amide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 1 carbon atom). 16, particularly preferably a phosphoric acid amide group having 1 to 12 carbon atoms, such as a diethylphosphoric acid amide group and a phenylphosphoric acid amide group, a hydroxy group, a mercapto group, a halogen atom (for example, a fluorine atom) , Chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group A sulfino group, a hydrazino group, an imino group, a heterocyclic group (preferably a heterocyclic group having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms such as a nitrogen atom, an oxygen atom, a sulfur atom, etc. For example, an imidazolyl group, a pyridyl group, a quinolyl group, a furyl group, a piperidyl group, a morpholino group, a benzoxazolyl group, a benzimidazolyl group, a benzthiazolyl group), a silyl group (preferably A silyl group having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms, and examples thereof include a trimethylsilyl group and a triphenylsilyl group) It is. These substituents may be further substituted with these substituents. Further, when two or more substituents are present, they may be the same or different. If possible, they may be bonded to each other to form a ring.

  The fluorine-containing compound preferably has a polymerizable group as a substituent in order to fix the molecular alignment state of the rod-like liquid crystalline compound.

  Specific examples of the fluorine-containing compound represented by the general formula (2) that can be used in the present invention and other compounds are shown below, but the fluorine-containing compound used in the present invention is not limited thereto.

  The preferred range of the content of the fluorine-containing compound in the composition used in the present invention varies depending on the application, but when used for forming the optically anisotropic layer, the composition (excluding the solvent in the case of a coating solution) is excluded. The composition is preferably 0.005 to 8% by mass, more preferably 0.01 to 5% by mass, and still more preferably 0.05 to 1% by mass.

<< Other materials in the composition used in the present invention >>
The composition used in the present invention may contain a polymerization initiator, a plasticizer, a surfactant, a polymerizable monomer, and the like together with the rod-like liquid crystal compound, the onium salt, and the air interface vertical alignment agent. These materials are added for various purposes, for example, for the purpose of fixing the orientation, uniformity of the coating film, strength of the film, and improving the orientation of the liquid crystal compound. These materials are preferably compatible with the rod-like liquid crystal compound used in combination and do not inhibit the alignment.

As the polymerization initiator, either a thermal polymerization initiator or a photopolymerization initiator may be used, and a photopolymerization initiator is preferable. Examples of the photopolymerization initiator include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (described in US Pat. No. 2,448,828), α-hydrocarbon substituted aromatic acyloin. Compound (described in US Pat. No. 2,722,512), polynuclear quinone compound (described in US Pat. Nos. 3,046,127 and 2,951,758), a combination of triarylimidazole dimer and p-aminophenyl ketone (US Pat. No. 3,549,367) Acridine and phenazine compounds (JP-A-60-105667, U.S. Pat. No. 4,239,850) and oxadiazole compounds (U.S. Pat. No. 4,212,970).
The amount of the photopolymerization initiator used is preferably 0.01 to 20% by mass, more preferably 0.5 to 5% by mass, based on the solid content of the coating solution.

  Examples of the polymerizable monomer include radically polymerizable or cationically polymerizable compounds. Preferably, it is a polyfunctional radically polymerizable monomer and is preferably copolymerizable with the above-described polymerizable group-containing liquid crystal compound. Examples thereof include those described in paragraph numbers [0018] to [0020] in JP-A No. 2002-296423. The addition amount of the above compound is preferably in the range of 1 to 50% by mass and more preferably in the range of 5 to 30% by mass with respect to the rod-like liquid crystal compound.

  Examples of the surfactant include conventionally known compounds, and fluorine compounds are particularly preferable. Specific examples include the compounds described in paragraph numbers [0028] to [0056] in JP-A-2001-330725. Examples of the surfactant that can be used in the present invention include the following compounds P-1 to P-71.

The polymer used together with the rod-like liquid crystalline compound is preferably capable of thickening the coating solution.
A cellulose ester can be mentioned as an example of a polymer. Preferable examples of the cellulose ester include those described in paragraph No. [0178] of JP-A No. 2000-155216. The addition amount of the polymer is preferably in the range of 0.1 to 10% by mass, and in the range of 0.1 to 8% by mass with respect to the liquid crystal compound so as not to inhibit the alignment of the liquid crystal compound. It is more preferable.

<< Method for producing optically anisotropic layer >>
The optically anisotropic layer is prepared by applying the composition used in the present invention as a coating liquid, coating the coating liquid on the surface of a support or the like, vertically aligning the molecules of the rod-like liquid crystalline compound, and changing the alignment state. It can be formed by fixing. When the optically anisotropic layer is formed on the temporary support, the formed optically anisotropic layer is transferred onto the support. Furthermore, not only one optically anisotropic layer but also a plurality of optically anisotropic layers can be laminated to form the second retardation region exhibiting the above optical characteristics. Further, the second retardation region may be produced so that the entire laminated body of the support and the optically anisotropic layer satisfies the optical characteristics.

  As a solvent used for preparing the coating solution, an organic solvent is preferably used. Examples of organic solvents include amides (eg N, N-dimethylformamide), sulfoxides (eg dimethyl sulfoxide), heterocyclic compounds (eg pyridine), hydrocarbons (eg benzene, hexane), alkyl halides (eg , Chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane). Alkyl halides and ketones are preferred. Two or more organic solvents may be used in combination.

  Application | coating of a coating liquid can be implemented by a well-known method (For example, extrusion coating method, direct gravure coating method, reverse gravure coating method, die coating method).

After the molecules of the rod-like liquid crystalline compound are vertically aligned, it is preferable to fix the molecules in the alignment state. The immobilization is preferably carried out by a polymerization reaction of the polymerizable monomer when the rod-like liquid crystalline compound has a polymerizable group, and / or when the polymerizable monomer is added separately. For the polymerization reaction carried out for immobilization, it is preferable to use a photopolymerization reaction using a photopolymerization initiator. The light irradiation for the polymerization of the rod-like liquid crystalline compound preferably uses ultraviolet rays. The irradiation energy is preferably ^{20mJ / cm 2 ~50J / cm 2} , further preferably 100 to 800 mJ / cm ^2. In order to accelerate the photopolymerization reaction, light irradiation may be performed under heating conditions.

When the heating temperature at the time of photopolymerization is too high, there is a problem that the liquid crystalline compound becomes isotropic phase or the nematic liquid crystal phase is disturbed. On the other hand, if the heating temperature is too low, the liquid crystal compound crystallizes and the orientation is disturbed, the polymerization rate is low, the adhesion between the optically anisotropic layer and the orientation film is insufficient, or the mechanical strength of the optically anisotropic layer is insufficient. To do.
From the above problems, it is important to control the temperature during photopolymerization, and there is no particular limitation as long as the temperature does not cause the above problems, but specifically, a range of 40 to 80 ° C. is preferable. More preferably, it is 50-70 degreeC.

  The thickness of the optically anisotropic layer (optically anisotropic film) is preferably 0.1 to 10 μm, more preferably 0.5 to 5 μm, and most preferably 1 to 5 μm. .

(Alignment film)
An alignment film may be used for the production of the optically anisotropic layer. The alignment film has a function of defining the alignment direction of the rod-like liquid crystal compound. However, when the molecules of the rod-like liquid crystalline compound are homeotropically aligned, since there is no in-plane alignment direction, the alignment film is not essential in the present invention.
Further, since the composition used in the present invention contains an onium salt and an air interface vertical alignment agent, the molecules of the rod-like liquid crystalline compound can be stably vertically aligned without using a vertical alignment film. A vertical alignment film is not essential for forming the optically anisotropic layer. However, since the alignment film can improve the uniformity of alignment of the liquid crystalline composition or improve the adhesion between the polymer substrate and the optically anisotropic layer, it can be used if necessary. it can. Further, if the molecules of the rod-like liquid crystal compound are aligned and fixed in the alignment state, the alignment film plays the role and can be removed. For example, it is possible to produce a polarizing plate having an optically anisotropic layer by transferring only the optically anisotropic layer on the alignment film in which the alignment state is fixed onto a polarizer.

  The alignment film is an organic compound (for example, ω-tricosanoic acid) formed by rubbing treatment of an organic compound (preferably a polymer), oblique deposition of an inorganic compound, formation of a layer having a microgroove, or Langmuir-Blodget method (LB film). , Dioctadecylmethylammonium chloride, methyl stearylate). Furthermore, an alignment film in which an alignment function is generated by application of an electric field, application of a magnetic field, or light irradiation is also known.

The alignment film can be rubbed if necessary. In principle, the polymer used for the alignment film has a molecular structure having a function of aligning the liquid crystal compound.
In the present invention, in addition to the function of aligning the liquid crystalline compound, the cross-linking having a function of binding a side chain having a crosslinkable functional group (for example, a double bond) to the main chain or aligning the liquid crystalline compound. It is preferable to introduce a functional functional group into the side chain.
As the polymer used for the alignment film, either a polymer that can be crosslinked by itself or a polymer that is crosslinked by a crosslinking agent can be used, and a plurality of combinations thereof can be used.

  Examples of the polymer include, for example, methacrylate polymer, styrene polymer, polyolefin, polyvinyl alcohol and modified polyvinyl alcohol, poly (N-methylolacrylamide) described in JP-A-8-338913, paragraph [0022]. , Polyester, polyimide, vinyl acetate polymer, carboxymethyl cellulose, polycarbonate and the like. Silane coupling agents can be used as the polymer. Water-soluble polymers (for example, poly (N-methylolacrylamide), carboxymethylcellulose, gelatin, polyvinyl alcohol, and modified polyvinyl alcohol) are preferable, gelatin, polyvinyl alcohol, and modified polyvinyl alcohol are more preferable, and polyvinyl alcohol and modified polyvinyl alcohol are most preferable. . It is particularly preferable to use two types of polyvinyl alcohol or modified polyvinyl alcohol having different degrees of polymerization.

  The saponification degree of polyvinyl alcohol is preferably 70 to 100%, more preferably 80 to 100%. It is preferable that the polymerization degree of polyvinyl alcohol is 100-5000.

The side chain having the function of aligning the liquid crystal compound generally has a hydrophobic group as a functional group.
The specific type of functional group is determined according to the type of liquid crystal compound and the required alignment state.
For example, the modifying group of the modified polyvinyl alcohol can be introduced by copolymerization modification, chain transfer modification or block polymerization modification. Examples of modifying groups include hydrophilic groups (carboxylic acid groups, sulfonic acid groups, phosphonic acid groups, amino groups, ammonium groups, amide groups, thiol groups, etc.), hydrocarbon groups having 10 to 100 carbon atoms, fluorine Atom-substituted hydrocarbon groups, thioether groups, polymerizable groups (unsaturated polymerizable groups, epoxy groups, azirinidyl groups, etc.), alkoxysilyl groups (trialkoxy groups, dialkoxy groups, monoalkoxy groups) and the like can be mentioned. As specific examples of these modified polyvinyl alcohol compounds, for example, paragraph numbers [0022] to [0145] in JP-A No. 2000-155216 and paragraph numbers [0018] to [0018] in JP-A No. 2002-62426 are described. [0022] and the like.

When the side chain having a crosslinkable functional group is bonded to the main chain of the alignment film polymer or the crosslinkable functional group is introduced into the side chain having a function of aligning the liquid crystalline compound, the alignment film polymer and the optically anisotropic film The polyfunctional monomer contained in the conductive layer can be copolymerized. As a result, not only between the polyfunctional monomer and the polyfunctional monomer, but also between the alignment film polymer and the alignment film polymer and between the polyfunctional monomer and the alignment film polymer is firmly bonded by a covalent bond. Therefore, the strength of the optical compensation sheet can be remarkably improved by introducing the crosslinkable functional group into the alignment film polymer.
The crosslinkable functional group of the alignment film polymer preferably contains a polymerizable group in the same manner as the polyfunctional monomer. Specific examples include those described in paragraphs [0080] to [0100] in JP-A-2000-155216.

Apart from the crosslinkable functional group, the alignment film polymer can also be crosslinked using a crosslinking agent.
Examples of the crosslinking agent include aldehydes, N-methylol compounds, dioxane derivatives, compounds that act by activating carboxyl groups, active vinyl compounds, active halogen compounds, isoxazole, and dialdehyde starch. Two or more kinds of crosslinking agents may be used in combination. Specific examples include compounds described in paragraphs [0023] to [0024] in JP-A-2002-62426. Aldehydes having high reaction activity, particularly glutaraldehyde are preferred.

  0.1-20 mass% is preferable with respect to a polymer, and, as for the addition amount of a crosslinking agent, 0.5-15 mass% is more preferable. The amount of the unreacted crosslinking agent remaining in the alignment film is preferably 1.0% by mass or less, and more preferably 0.5% by mass or less. By adjusting in this way, even if the alignment film is used for a long time in a liquid crystal display device or left in a high temperature and high humidity atmosphere for a long time, sufficient durability without reticulation can be obtained.

  The alignment film can basically be formed by applying the above-mentioned polymer as an alignment film forming material and a support containing a crosslinking agent, followed by drying by heating (crosslinking) and, if necessary, rubbing treatment. it can. As described above, the crosslinking reaction may be performed at an arbitrary time after coating on the support. When a water-soluble polymer such as polyvinyl alcohol is used as the alignment film forming material, the coating solution is preferably a mixed solvent of an organic solvent (for example, methanol) having a defoaming action and water. The ratio by mass is water: methanol greater than 0 and 99 or less: less than 100, preferably 1 or more, and more preferably greater than 0 and 91 or less: less than 100, 9 or more. Thereby, generation | occurrence | production of a bubble is suppressed and the defect of the layer surface of an orientation film and also an optically anisotropic layer reduces remarkably.

  The alignment film is preferably applied by spin coating, dip coating, curtain coating, extrusion coating, rod coating, or roll coating. A rod coating method is particularly preferable. The film thickness after drying is preferably 0.1 to 10 μm. Heat drying can be performed at 20 to 110 degrees. In order to form sufficient cross-linking, 60 ° to 100 ° is preferable, and 80 ° to 100 ° is particularly preferable. The drying time can be 1 minute to 36 hours, preferably 1 minute to 30 minutes. The pH is preferably set to an optimum value for the crosslinking agent to be used. When glutaraldehyde is used, the pH is 4.5 to 5.5, and 5 is particularly preferable.

  The alignment film is provided on the support or on the undercoat layer. The alignment film can be obtained by cross-linking the polymer layer as described above and, if necessary, rubbing the surface.

  For the rubbing treatment, a treatment method widely adopted as a liquid crystal alignment treatment process of LCD can be applied. That is, a method of obtaining the orientation by rubbing the surface of the orientation film in a certain direction using paper, gauze, felt, rubber, nylon, polyester fiber or the like can be used. Generally, it is carried out by rubbing several times using a cloth or the like in which fibers having a uniform length and thickness are planted on average.

  After aligning the liquid crystalline compound on the alignment film, if necessary, the alignment film polymer is reacted with the polyfunctional monomer contained in the optically anisotropic layer, or the alignment film polymer is formed using a crosslinking agent. It may be cross-linked. The thickness of the alignment film is preferably in the range of 0.1 to 10 μm.

  In order to uniformly align the rod-like liquid crystalline compound, it is preferable to control the alignment direction with an alignment film. In addition, after aligning a liquid crystalline compound using an alignment film, the liquid crystalline compound is fixed in the alignment state to form an optically anisotropic layer, and only the optically anisotropic layer is formed as a polymer film (or a support). ) May be transferred onto. That is, even if an alignment film is used when the optically anisotropic layer is produced, the alignment film is not necessarily a constituent member of the retardation film of the present invention.

[Support]
In the present invention, the optically anisotropic layer may be formed on a support. The support is preferably transparent, and specifically, the light transmittance is preferably 80% or more. The support preferably has a small wavelength dispersion, and specifically, the ratio of Re ₄₀₀ / Re ₇₀₀ is preferably less than 1.2. Among these, a polymer film is preferable. The support for the optically anisotropic layer may be a part of the second retardation region, or a part or the whole of the first retardation region. The support of the optically anisotropic layer may also function as a protective film for the polarizing film.

  The optical anisotropy of the support is preferably small, and the in-plane retardation (Re) is preferably 20 nm or less, more preferably 10 nm or less, and most preferably 5 nm or less. Moreover, when serving also as a 1st phase difference area | region, it is preferable that Re is 20 nm-150 nm, It is more preferable that it is 40 nm-115 nm, It is more preferable that it is 60 nm-95 nm. Moreover, Nz is 1.5-7, it is more preferable that it is 2.0-5.5, and it is further more preferable that it is 2.5-4.5.

  Examples of the polymer film as the support include cellulose ester, polycarbonate, polysulfone, polyethersulfone, polyacrylate, and polymethacrylate films. A cellulose ester film is preferred, an acetyl cellulose film is more preferred, and a triacetyl cellulose film is most preferred. The polymer film is preferably formed by a solvent cast method. The thickness of the support is preferably 20 to 500 μm, and more preferably 40 to 200 μm. In order to improve the adhesion between the support and the layer (adhesive layer, vertical alignment film or retardation layer) provided thereon, the support is subjected to surface treatment (for example, glow discharge treatment, corona discharge treatment, ultraviolet ray (UV) treatment). , Flame treatment). An adhesive layer (undercoat layer) may be provided on the support. Moreover, in order to give the support body and the long support body the slipperiness in a conveyance process, or to prevent sticking of the back surface and the surface after winding up, an average particle size is about 10-100 nm. It is preferable to use a polymer layer in which inorganic particles are mixed at a solid content weight ratio of 5% to 40% and formed on one side of the support by coating or co-casting with the support.

[Polarizing plate protective film]
As the first and second polarizing plate protective films, those having no absorption in the visible light region, light transmittance of 80% or more, and small retardation based on birefringence are preferable. Specifically, the in-plane Re is preferably 0 to 30 nm, more preferably 0 to 15 nm, and most preferably 0 to 5 nm. Further, the retardation Rth in the thickness direction is preferably in the range of −40 to 40 nm, more preferably −20 to 20 nm, further preferably −10 to 10 nm, and further preferably −5 to 5 nm. Most preferred. Any film having this property can be preferably used, but from the viewpoint of durability of the polarizing film, a cellulose acylate or norbornene film is more preferable. More preferred are cellulose acylate and norbornene-based polymers exemplified for the birefringent polymer in the first retardation region. Examples of a method for reducing Rth of the cellulose acylate film include methods described in JP-A Nos. 11-246704, 2001-247717, and Japanese Patent Application No. 2003-379975. Rth can also be reduced by reducing the thickness of the polarizing plate protective film. The thickness of the cellulose sylate film as the first and second polarizing plate protective films is preferably 10 to 100 μm, more preferably 10 to 60 μm, and still more preferably 20 to 45 μm. By using the polarizing plate protective film having such characteristics, it is possible to increase the contrast while suppressing the luminance when observed from the polar angle direction of 60 ° during the black display of the liquid crystal panel. In addition, it is possible to suppress a color change when the azimuth angle direction is swung in the polar angle direction of 60 °.

Specifically, the cellulose acylate film having a small optical anisotropy (Re, Rth) of the present invention has an in-plane retardation Re _{(630) at} a wavelength of 630 nm of 10 nm or less (0 ≦ Re ₍₆₃₀₎ ≦ 10. And the absolute value of retardation Rth _{(630) in} the film thickness direction is preferably 25 nm or less (| Rth | ≦ 25 nm). More preferably, 0 ≦ Re ₍₆₃₀₎ ≦ 5 and | Rth | ≦ 20 nm, and further preferably 0 ≦ Re ₍₆₃₀₎ ≦ 2 and | Rth | ≦ 15 nm.
In addition, those having small retardation wavelength dispersion are preferable, and | Re ₍₄₀₀₎ −Re ₍₇₀₀₎ | ≦ 10 and | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | ≦ 35 are preferable. More preferably, | Re ₍₄₀₀₎ −Re ₍₇₀₀₎ | ≦ 5 and | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | ≦ 25, and more preferably | Re ₍₄₀₀₎ −Re ₍₇₀₀₎ | ≦ 3 and | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | ≦ 15.

A cellulose acylate film having a small optical anisotropy and a small wavelength dispersion of Re and Rth can be produced, for example, by the following method.
[Cellulose acylate raw cotton]
Cellulose acylate raw material cellulose used in the present invention includes cotton linter and wood pulp (hardwood pulp, softwood pulp), etc., and any cellulose acylate obtained from any raw material cellulose can be used. May be. Detailed descriptions of these raw material celluloses are, for example, Plastic Materials Course (17) Fibrous resin (Maruzawa, Uda, Nikkan Kogyo Shimbun, published in 1970) and Invention Association Open Technical Report 2001-1745 (page 7). To page 8), and any method can be preferably employed for the cellulose acylate film used in the present invention.

[Substitution degree of cellulose acylate]
Next, the cellulose acylate of the present invention produced from the above-mentioned cellulose will be described. The cellulose acylate of the present invention is obtained by acylating a hydroxyl group of cellulose, and as the substituent, for example, an acetyl group having 2 to 22 carbon atoms of the acyl group can be used. In the cellulose acylate of the present invention, the degree of substitution of cellulose with a hydroxyl group is not particularly limited, but the degree of binding of acetic acid and / or a fatty acid having 3 to 22 carbon atoms substituted with a hydroxyl group of cellulose is measured and substituted by calculation. You can get a degree. As a measuring method, it can carry out according to ASTM D-817-91.

  As described above, in the cellulose acylate of the present invention, the degree of substitution of the cellulose with a hydroxyl group is not particularly limited, but the degree of acyl substitution with the hydroxyl group of cellulose is preferably 2.50 to 3.00. Furthermore, the substitution degree is preferably 2.75 to 3.00, and more preferably 2.85 to 3.00.

  Among the acetic acid substituted for the hydroxyl group of cellulose and / or the fatty acid having 3 to 22 carbon atoms, the acyl group having 2 to 22 carbon atoms is not particularly limited and may be an aliphatic group or an allyl group. It may be a mixture of more than one type. They are, for example, an alkylcarbonyl ester group, an alkenylcarbonyl ester group, an aromatic carbonyl ester group, an aromatic alkylcarbonyl ester group or the like of cellulose, and each may further have a substituted group. As these preferable acyl groups, acetyl group, propionyl group, butanoyl group, heptanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group , Isobutanoyl group, tert-butanoyl group, cyclohexanecarbonyl group, oleoyl group, benzoyl group, naphthylcarbonyl group, cinnamoyl group and the like. Among these, acetyl group, propionyl group, butanoyl group, dodecanoyl group, octadecanoyl group, tert-butanoyl group, oleoyl group, benzoyl group, naphthylcarbonyl group, cinnamoyl group and the like are preferable, and acetyl group, propionyl group, butanoyl group are preferable. Groups are more preferred.

  As a result of intensive studies by the inventor of the present invention, among the acyl substituents substituted on the above-mentioned cellulose hydroxyl group, in the case of substantially consisting of at least two kinds of acetyl group / propionyl group / butanoyl group, the total substitution It was found that the optical anisotropy of the cellulose acylate film can be lowered when the degree is 2.50 to 3.00. The degree of acyl substitution is more preferably 2.60 to 3.00, and even more preferably 2.65 to 3.00.

[Structural characteristics of compounds that reduce the optical anisotropy of cellulose acylate films]
The compound that reduces the optical anisotropy of the cellulose acylate film will be described. As a result of intensive studies, the inventors of the present invention have sufficiently reduced the optical anisotropy by using a compound that suppresses the orientation of cellulose acylate in the film in the plane and in the film thickness direction. Zero and Rth were close to zero. For this purpose, it is advantageous that the compound that lowers the optical anisotropy is sufficiently compatible with cellulose acylate, and the compound itself does not have a rod-like structure or a planar structure. Specifically, when a plurality of planar functional groups such as aromatic groups are provided, a structure having these functional groups in a non-planar rather than the same plane is advantageous.

(Log P value)
In producing the cellulose acylate film of the present invention, as described above, octanol is a compound that reduces optical anisotropy by inhibiting the cellulose acylate in the film from being oriented in the plane and in the film thickness direction. -The compound whose water partition coefficient (logP value) is 0-7 is preferable. A compound having a log P value of more than 7 is poor in compatibility with cellulose acylate, and tends to cause film turbidity or powder blowing. In addition, since a compound having a log P value smaller than 0 has high hydrophilicity, the water resistance of the cellulose acetate film may be deteriorated. A more preferable range for the logP value is 1 to 6, and a particularly preferable range is 1.5 to 5.
The octanol-water partition coefficient (log P value) can be measured by a flask immersion method described in JIS Japanese Industrial Standard Z7260-107 (2000). Further, the octanol-water partition coefficient (log P value) can be estimated by a computational chemical method or an empirical method instead of the actual measurement. As a calculation method, Crippen's fragmentation method (J. Chem. Inf. Comput. Sci., 27, 21 (1987).), Viswanadhan's fragmentation method (J. Chem. Inf. Comput. Sci., 29, 163 (1989).) Broto's fragmentation method (Eur. J. Med. Chem.- Chim. Theor., 19, 71 (1984).) And the like are preferably used, but Crippen's fragmentation method (J. Chem. Inf. Comput. Sci., 27 , 21 (1987). When the log P value of a certain compound varies depending on the measurement method or calculation method, it is preferable to determine whether or not the compound is within the scope of the present invention by the Crippen's fragmentation method.

[Physical properties of compounds that reduce optical anisotropy]
The compound that reduces optical anisotropy may or may not contain an aromatic group. The compound that reduces optical anisotropy preferably has a molecular weight of 150 to 3000, more preferably 170 to 2000, and even more preferably 200 to 1000. A specific monomer structure may be used as long as these molecular weights are within the range, and an oligomer structure or a polymer structure in which a plurality of the monomer units are bonded may be used.
The compound that reduces optical anisotropy is preferably a liquid at 25 ° C. or a solid having a melting point of 25 to 250 ° C., more preferably a liquid at 25 ° C. or a melting point of 25 to 200 ° C. It is a solid. Moreover, it is preferable that the compound which reduces optical anisotropy is a compound which does not volatilize in the process of dope casting at the time of preparation of a cellulose acylate film and drying.
The addition amount of the compound that decreases the optical anisotropy is preferably 0.01 to 30% by mass of the cellulose acylate, more preferably 1 to 25% by mass, and 5 to 20% by mass. Is particularly preferred.
The compound that decreases the optical anisotropy may be used alone, or two or more compounds may be mixed and used in an arbitrary ratio.
The timing for adding the compound for reducing the optical anisotropy may be any time during the dope preparation process, or may be performed at the end of the dope preparation process.

  The compound that reduces the optical anisotropy is such that the average content of the compound in the portion from the surface on at least one side to 10% of the total film thickness is the average content of the compound in the central portion of the cellulose acylate film. It is 80 to 99%. The abundance of the compound of the present invention can be determined, for example, by measuring the amount of the compound at the surface and in the center by the method using an infrared absorption spectrum described in JP-A-8-57879.

  Specific examples of the compound for reducing the optical anisotropy of the cellulose acylate film preferably used in the present invention are represented by any of the following general formulas (13), (18), and (19). Although a compound is mentioned, this invention is not limited to these compounds.

[In General Formula (13), R ¹ represents an alkyl group or an aryl group, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group, or an aryl group. However, the total number of carbon atoms of R ¹ , R ² and R ³ is 10 or more. ]

[In General Formula (18), R ¹ represents an alkyl group or an aryl group, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group, or an aryl group. ]

[In the general formula (19), R ⁴ , R ⁵ and R ⁶ each independently represents an alkyl group or an aryl group. ]

The compound of the general formula (13) will be described.
In the general formula (13), R ¹ represents an alkyl group or an aryl group, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group, or an aryl group. Further, the total number of carbon atoms of R ¹ , R ² and R ³ is particularly preferably 10 or more. R ¹ , R ² and R ³ may be substituted, and the substituent is preferably a fluorine atom, an alkyl group, an aryl group, an alkoxy group, a sulfone group and a sulfonamide group, and an alkyl group, an aryl group, an alkoxy group, A sulfone group and a sulfonamide group are particularly preferred. Further, the alkyl group may be linear, branched or cyclic, and preferably has 1 to 25 carbon atoms, more preferably 6 to 25, and more preferably 6 to 20 (For example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, amyl, isoamyl, tert-amyl, hexyl, cyclohexyl, heptyl, octyl, bicyclo Octyl, nonyl, adamantyl, decyl, tert-octyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, didecyl) are particularly preferred. . As the aryl group, those having 6 to 30 carbon atoms are preferable, and those having 6 to 24 carbon atoms (for example, phenyl group, biphenyl group, terphenyl group, naphthyl group, binaphthyl group, triphenylphenyl group) are particularly preferable. Preferred examples of the compound represented by the general formula (13) are shown below, but the present invention is not limited to these specific examples.

  Although the preferable example of a compound represented by General formula (18) or General formula (19) below is shown below, this invention is not limited to these specific examples. In the compound represented by the general formula (18) or the general formula (19), specific examples of the alkyl group and the aryl group are the same as those in the general formula (13).

In the formula, Pr ⁱ represents an isopropyl group.

[Wavelength dispersion modifier]
A compound for reducing the wavelength dispersion of the cellulose acylate film (hereinafter also referred to as “wavelength dispersion adjusting agent”) will be described. In order to improve the Rth wavelength dispersion of the cellulose acylate film of the present invention, a compound that reduces the Rth wavelength dispersion ΔRth = | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | represented by the following formula (iv): Is preferably contained within the range satisfying the following formulas (v) and (vi).
(Iv) ΔRth = | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ |
(V) (ΔRth (B) −ΔRth (0)) / B ≦ −2.0
(Vi) 0.01 ≦ B ≦ 30
The above formulas (v) and (vi)
(V) (ΔRth (B) −ΔRth (0)) / B ≦ −3.0
(Vi) 0.05 ≦ B ≦ 25
(V) (ΔRth (B) −ΔRth (0)) / B ≦ −4.0
(Vi) 0.1 ≦ B ≦ 20
More preferably.
The above-mentioned wavelength dispersion adjusting agent has at least a compound having absorption in the ultraviolet region of 200 to ₄₀₀ nm and reducing | Re ₍₄₀₀₎ -Re ₍₇₀₀₎ | and | Rth ₍₄₀₀₎ -Rth ₍₇₀₀₎ | The wavelength dispersion of Re and Rth of the cellulose acylate film was adjusted by including 0.01 to 30% by weight of one type, cellulose acylate solid content. By adding 0.1 to 30% by weight as the addition amount, wavelength dispersion of Re and Rth of the cellulose acylate film was adjusted.

  In general, the Re and Rth values of the cellulose acylate film have a wavelength dispersion characteristic that the longer wavelength side is larger than the shorter wavelength side. Therefore, it is required to smooth the chromatic dispersion by increasing Re and Rth on the relatively short wavelength side. On the other hand, a compound having absorption in the ultraviolet region of 200 to 400 nm has a wavelength dispersion characteristic in which the absorbance on the long wavelength side is larger than that on the short wavelength side. If the compound itself is isotropically present inside the cellulose acylate film, it is assumed that the birefringence of the compound itself, and thus the wavelength dispersion of Re and Rth, is large on the short wavelength side as well as the wavelength dispersion of absorbance. .

  Therefore, as described above, by using the compound having absorption in the ultraviolet region of 200 to 400 nm and assuming that the wavelength dispersion of Re and Rth of the compound itself is large on the short wavelength side, the Re and Rth of the cellulose acylate film are used. Chromatic dispersion can be prepared. For this purpose, the compound for adjusting the wavelength dispersion is required to be sufficiently homogeneously compatible with the cellulose acylate. The absorption band range in the ultraviolet region of such a compound is preferably 200 to 400 nm, more preferably 220 to 395 nm, and even more preferably 240 to 390 nm.

In recent years, liquid crystal display devices such as televisions, notebook personal computers, and mobile portable terminals have been required to have excellent transmittance of optical members used in liquid crystal display devices in order to increase luminance with less power. In that respect, a cellulose acylate film is a compound having absorption in the ultraviolet region of 200 to ₄₀₀ nm and reducing | Re ₍₄₀₀₎ -Re ₍₇₀₀₎ | and | Rth ₍₄₀₀₎ -Rth ₍₇₀₀₎ | When it is added, it is required to have excellent spectral transmittance. In the cellulose acylate film of the present invention, the spectral transmittance at a wavelength of 380 nm is preferably 45% to 95%, and the spectral transmittance at a wavelength of 350 nm is preferably 10% or less.

  As described above, the wavelength dispersion adjusting agent preferably used in the present invention preferably has a molecular weight of 250 to 1000 from the viewpoint of volatility. More preferably, it is 260-800, More preferably, it is 270-800, Most preferably, it is 300-800. A specific monomer structure may be used as long as these molecular weights are within the range, and an oligomer structure or a polymer structure in which a plurality of the monomer units are bonded may be used.

  It is preferable that the wavelength dispersion adjusting agent does not volatilize during the dope casting and drying process for producing the cellulose acylate film.

(Compound addition amount)
The addition amount of the wavelength dispersion adjusting agent preferably used in the present invention described above is preferably 0.01 to 30% by weight, more preferably 0.1 to 20% by weight of cellulose acylate, and 2 to 10% by weight is particularly preferred.

(Method of compound addition)
These wavelength dispersion adjusting agents may be used alone or in combination of two or more compounds at an arbitrary ratio.
Further, the timing of adding these wavelength dispersion adjusting agents may be any time during the dope preparation process, or may be performed at the end of the dope preparation process.

  Specific examples of the wavelength dispersion adjusting agent preferably used in the present invention include, for example, benzotriazole compounds, benzophenone compounds, cyano group-containing compounds, oxybenzophenone compounds, salicylic acid ester compounds, nickel complex compounds, and the like. However, the present invention is not limited to these compounds.

  As the benzotriazole-based compound, those represented by the general formula (101) are preferably used as the wavelength dispersion adjusting agent of the present invention.

Formula (101) Q ¹ -Q ² -OH
(In the formula, Q ¹ represents a nitrogen-containing aromatic heterocycle, and Q ² represents an aromatic ring.)

Q ¹ represents a nitrogen-containing aromatic heterocycle, preferably a 5-membered to 7-membered nitrogen-containing aromatic heterocycle, more preferably a 5-membered or 6-membered nitrogen-containing aromatic heterocycle. For example, imidazole ring, pyrazole ring, triazole ring, tetrazole ring, thiazole ring, oxazole ring, selenazole ring, benzotriazole ring, benzothiazole ring, benzoxazole ring, benzoselenazole ring, thiadiazole ring, oxadiazole ring , Naphthothiazole ring, naphthoxazole ring, azabenzimidazole ring, purine ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, triazine ring, triazaindene ring, tetrazaindene ring, etc., more preferably A 5-membered nitrogen-containing aromatic heterocycle, specifically an imidazole ring, Razoru ring, triazole ring, tetrazole ring, thiazole ring, oxazole ring, benzotriazole ring, benzothiazole ring, benzoxazole ring, thiadiazole ring, oxadiazole ring are preferred, particularly preferably a benzotriazole ring.
The nitrogen-containing aromatic heterocycle represented by Q ¹ may further have a substituent, and the substituent T described below can be applied as the substituent. In addition, when there are a plurality of substituents, each may be condensed to form a ring.

The aromatic ring represented by Q ² may be an aromatic hydrocarbon ring or an aromatic heterocycle. These may be monocyclic or may form a condensed ring with another ring.
The aromatic hydrocarbon ring is preferably (preferably a monocyclic or bicyclic aromatic hydrocarbon ring having 6 to 30 carbon atoms (for example, a benzene ring, a naphthalene ring, etc.), more preferably a carbon atom. An aromatic hydrocarbon ring having 6 to 20 carbon atoms, more preferably an aromatic hydrocarbon ring having 6 to 12 carbon atoms.) More preferably, it is a benzene ring.
The aromatic heterocycle is preferably an aromatic heterocycle containing a nitrogen atom or a sulfur atom. Specific examples of the hetero ring include, for example, thiophene ring, imidazole ring, pyrazole ring, pyridine ring, pyrazine ring, pyridazine ring, triazole ring, triazine ring, indole ring, indazole ring, purine ring, thiazoline ring, thiazole ring, thiadiazole. Ring, oxazoline ring, oxazole ring, oxadiazole ring, quinoline ring, isoquinoline ring, phthalazine ring, naphthyridine ring, quinoxaline ring, quinazoline ring, cinnoline ring, pteridine ring, acridine ring, phenanthroline ring, phenazine ring, tetrazole ring, benz Examples include an imidazole ring, a benzoxazole ring, a benzthiazole ring, a benzotriazole ring, and a tetrazaindene ring. The aromatic hetero ring is preferably a pyridine ring, a triazine ring or a quinoline ring.
The aromatic ring represented by Q ² is preferably an aromatic hydrocarbon ring, more preferably a naphthalene ring or a benzene ring, and particularly preferably a benzene ring. Q ² may further have a substituent, and the substituent T described later is preferable.
Examples of the substituent T include an alkyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, and examples thereof include a methyl group, an ethyl group, and an isopropyl group. , Tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (preferably having 2 to 20 carbon atoms, and more). Preferably it has 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, and examples thereof include vinyl, allyl group, 2-butenyl group and 3-pentenyl group), alkynyl group (preferably carbon atom) 2 to 20, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, such as propargyl group, 3-pentyl And aryl groups (preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms such as phenyl group and p-methyl). A phenyl group, a naphthyl group, etc.), a substituted or unsubstituted amino group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, and particularly preferably 0 to 6 carbon atoms). An amino group, a methylamino group, a dimethylamino group, a diethylamino group, a dibenzylamino group, etc.), an alkoxy group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, especially Preferably, it has 1 to 8 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, and a butoxy group.), An aryloxy group (preferably a carbon atom) 6 to 20, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as phenyloxy group and 2-naphthyloxy group), acyl group (preferably carbon 1 to 20 atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include an acetyl group, a benzoyl group, a formyl group, and a pivaloyl group.), An alkoxycarbonyl group (Preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, and examples thereof include a methoxycarbonyl group and an ethoxycarbonyl group), aryloxycarbonyl Group (preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms, particularly preferably having 7 to 10 carbon atoms) Examples thereof include a phenyloxycarbonyl group. ), An acyloxy group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include an acetoxy group and a benzoyloxy group). An acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include an acetylamino group and a benzoylamino group), alkoxy. A carbonylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as a methoxycarbonylamino group), aryloxycarbonyl An amino group (preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms such as phenyloxycarbonylamino group), sulfonylamino group (preferably 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably carbon atoms) 1 to 12, for example, methanesulfonylamino group, benzenesulfonylamino group, etc.), sulfamoyl group (preferably having 0 to 20 carbon atoms, more preferably having 0 to 16 carbon atoms, particularly preferably carbon The number of atoms is 0 to 12, and examples thereof include a sulfamoyl group, a methylsulfamoyl group, a dimethylsulfamoyl group, and a phenylsulfamoyl group.), A carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably Has 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms. Yl group, methylcarbamoyl group, diethylcarbamoyl group, phenylcarbamoyl group, etc.), alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 carbon atom). For example, a methylthio group, an ethylthio group, etc.), an arylthio group (preferably having 6 to 20 carbon atoms, more preferably having 6 to 16 carbon atoms, and particularly preferably having 6 to 12 carbon atoms). Yes, for example, a phenylthio group, etc.), a sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as a mesyl group, Tosyl groups, etc.), sulfinyl groups (preferably having 1 to 20 carbon atoms, more preferably carbon atoms). The number is from 1 to 16, particularly preferably from 1 to 12, and examples thereof include a methanesulfinyl group and a benzenesulfinyl group. ), A ureido group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include a ureido group, a methylureido group, and a phenylureido group. Phosphoric acid amide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms, such as diethyl phosphoric acid amide group, phenylphosphoric acid Amide group, etc.), hydroxy group, mercapto group, halogen atom (eg fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group, sulfino group , Hydrazino group, imino group, heterocyclic group (preferably having 1-30 carbon atoms, more preferably 1-12, As, for example, nitrogen atom, oxygen atom, sulfur atom, specifically, for example, imidazolyl group, pyridyl group, quinolyl group, furyl group, piperidyl group, morpholino group, benzoxazolyl group, benzimidazolyl group, benzthiazolyl group, etc. ), A silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms, such as a trimethylsilyl group or a triphenylsilyl group. Etc.). These substituents may be further substituted. Moreover, when there are two or more substituents, they may be the same or different. If possible, they may be linked together to form a ring.

As the general formula (101), a compound represented by the following general formula (101-A) is preferable.
General formula (101-A)

（式中、Ｒ¹、Ｒ²、Ｒ³、Ｒ⁴、Ｒ⁵、Ｒ⁶、Ｒ⁷、およびＲ⁸はそれぞれ独立に水素原子または置換基を表す。）

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , and R ⁸ each independently represents a hydrogen atom or a substituent)

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ each independently represent a hydrogen atom or a substituent, and the substituent T can be applied as the substituent. These substituents may be further substituted with another substituent, and the substituents may be condensed to form a ring structure.
R ¹ and R ³ are preferably hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, substituted or unsubstituted amino groups, alkoxy groups, aryloxy groups, hydroxy groups, and halogen atoms, more preferably hydrogen atoms. An atom, an alkyl group, an aryl group, an alkyloxy group, an aryloxy group and a halogen atom, more preferably a hydrogen atom and an alkyl group having 1 to 12 carbon atoms, particularly preferably an alkyl group having 1 to 12 carbon atoms (preferably Is from 4 to 12 carbon atoms.

R ² and R ⁴ are preferably a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a substituted or unsubstituted amino group, an alkoxy group, an aryloxy group, a hydroxy group, and a halogen atom, more preferably A hydrogen atom, an alkyl group, an aryl group, an alkyloxy group, an aryloxy group, and a halogen atom, more preferably a hydrogen atom and an alkyl group having 1 to 12 carbon atoms, particularly preferably a hydrogen atom and a methyl group, most preferably Is a hydrogen atom.

R ⁵ and R ⁸ are preferably hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, substituted or unsubstituted amino groups, alkoxy groups, aryloxy groups, hydroxy groups, and halogen atoms, more preferably hydrogen atoms. An atom, an alkyl group, an aryl group, an alkyloxy group, an aryloxy group, and a halogen atom, more preferably a hydrogen atom and an alkyl group having 1 to 12 carbon atoms, particularly preferably a hydrogen atom and a methyl group, most preferably It is a hydrogen atom.

R ⁶ and R ⁷ are preferably a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a substituted or unsubstituted amino group, an alkoxy group, an aryloxy group, a hydroxy group, and a halogen atom, more preferably a hydrogen atom. An atom, an alkyl group, an aryl group, an alkyloxy group, an aryloxy group, and a halogen atom, more preferably a hydrogen atom and a halogen atom, and particularly preferably a hydrogen atom and a chlorine atom.

（式中、Ｒ¹、Ｒ³、Ｒ⁶およびＲ⁷は一般式（１０１−Ａ）におけるそれらと同義であり、また好ましい範囲も同様である。） More preferable as the general formula (101) is a compound represented by the following general formula (101-B).
General formula (101-B)

(In formula, R < ¹ >, R < ³ >, R < ⁶ > and R < ⁷ > are synonymous with those in general formula (101-A), and their preferred ranges are also the same.)

Specific examples of the compound represented by the general formula (101) are given below, but the present invention is not limited to the following specific examples.

  As mentioned above, when the cellulose acylate film of the present invention was produced without including those having a molecular weight of 320 or less among the benzotriazole-based compounds given as examples, it was confirmed that the retention was advantageous.

（式中、Ｑ¹およびＱ²はそれぞれ独立に芳香族環を表す。ＸはＮＲ（Ｒは水素原子または置換基を表す。）、酸素原子または硫黄原子を表す。） In addition, as the benzophenone compound which is one of the wavelength dispersion adjusting agents used in the present invention, those represented by the general formula (102) are preferably used.
Formula (102)

(In the formula, Q ¹ and Q ² each independently represent an aromatic ring. X represents NR (R represents a hydrogen atom or a substituent), an oxygen atom or a sulfur atom.)

The aromatic ring represented by Q ¹ and Q ² may be an aromatic hydrocarbon ring or an aromatic heterocycle. These may be monocyclic or may form a condensed ring with another ring.
The aromatic hydrocarbon ring represented by Q ¹ and Q ² is preferably (preferably a monocyclic or bicyclic aromatic hydrocarbon ring having 6 to 30 carbon atoms (eg, benzene ring, naphthalene ring, etc.). More preferably, it is an aromatic hydrocarbon ring having 6 to 20 carbon atoms, more preferably an aromatic hydrocarbon ring having 6 to 12 carbon atoms.) More preferably, it is a benzene ring.
The aromatic heterocycle represented by Q ¹ and Q ² is preferably an aromatic heterocycle containing at least one of an oxygen atom, a nitrogen atom or a sulfur atom. Specific examples of the heterocyclic ring include, for example, furan ring, pyrrole ring, thiophene ring, imidazole ring, pyrazole ring, pyridine ring, pyrazine ring, pyridazine ring, triazole ring, triazine ring, indole ring, indazole ring, purine ring, thiazoline. Ring, thiazole ring, thiadiazole ring, oxazoline ring, oxazole ring, oxadiazole ring, quinoline ring, isoquinoline ring, phthalazine ring, naphthyridine ring, quinoxaline ring, quinazoline ring, cinnoline ring, pteridine ring, acridine ring, phenanthroline ring, phenazine Ring, tetrazole ring, benzimidazole ring, benzoxazole ring, benzthiazole ring, benzotriazole ring, tetrazaindene ring and the like. The aromatic hetero ring is preferably a pyridine ring, a triazine ring or a quinoline ring.
The aromatic ring represented by Q ¹ and Q ² is preferably an aromatic hydrocarbon ring, more preferably an aromatic hydrocarbon ring having 6 to 10 carbon atoms, and still more preferably a substituted or unsubstituted benzene. It is a ring.

Q ¹ and Q ² may further have a substituent, and the above-described substituent T is preferable, but the substituent does not contain a carboxylic acid, a sulfonic acid, or a quaternary ammonium salt. Further, if possible, substituents may be linked to form a ring structure.

  X represents NR (R represents a hydrogen atom or a substituent. As the substituent, the above-mentioned substituent T can be applied), an oxygen atom or a sulfur atom, X is preferably NR (R is preferably an acyl group) , A sulfonyl group, and these substituents may be further substituted.), Or O, particularly preferably O.

（式中、Ｒ¹、Ｒ²、Ｒ³、Ｒ⁴、Ｒ⁵、Ｒ⁶、Ｒ⁷、Ｒ⁸、およびＲ⁹はそれぞれ独立に水素原子または置換基を表す。） As the general formula (102), a compound represented by the following general formula (102-A) is preferable.
Formula (102-A)

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ each independently represents a hydrogen atom or a substituent.)

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ each independently represent a hydrogen atom or a substituent, and the above-mentioned substituent T is applied as the substituent. it can. These substituents may be further substituted with another substituent, and the substituents may be condensed to form a ring structure.

R ¹ , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ and R ⁹ are preferably a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, substituted or unsubstituted amino group, alkoxy group, aryl An oxy group, a hydroxy group and a halogen atom, more preferably a hydrogen atom, an alkyl group, an aryl group, an alkyloxy group, an aryloxy group and a halogen atom, still more preferably a hydrogen atom and a carbon 1-12 alkyl group. Particularly preferred are a hydrogen atom and a methyl group, and most preferred is a hydrogen atom.

R ² is preferably a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a substituted or unsubstituted amino group, an alkoxy group, an aryloxy group, a hydroxy group, a halogen atom, more preferably a hydrogen atom or a carbon atom number. An alkyl group having 1 to 20 carbon atoms, an amino group having 0 to 20 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, and a hydroxy group, and more preferably 1 to 1 carbon atom. 20 alkoxy groups, particularly preferably an alkoxy group having 1 to 12 carbon atoms.

R ⁷ is preferably a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, substituted or unsubstituted amino group, alkoxy group, aryloxy group, hydroxy group, halogen atom, more preferably a hydrogen atom or the number of carbon atoms An alkyl group having 1 to 20 carbon atoms, an amino group having 0 to 20 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, and a hydroxy group, more preferably a hydrogen atom and a carbon atom. It is an alkyl group having 1 to 20 carbon atoms (preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably a methyl group), and particularly preferably a methyl group or a hydrogen atom.

（式中、Ｒ¹⁰は水素原子、置換または無置換のアルキル基、置換または無置換のアルケニル基、置換または無置換のアルキニル基、置換または無置換のアリール基を表す。） More preferable as the general formula (102) is a compound represented by the following general formula (102-B).
General formula (102-B)

(Wherein R ¹⁰ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group.)

R ¹⁰ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. Applicable.
R ¹⁰ is preferably a substituted or unsubstituted alkyl group, more preferably a substituted or unsubstituted alkyl group having 5 to 20 carbon atoms, and still more preferably a substituted or unsubstituted group having 5 to 12 carbon atoms. An alkyl group (including n-hexyl group, 2-ethylhexyl group, n-octyl group, n-decyl group, n-dodecyl group, benzyl group, etc.), particularly preferably 6 to 12 carbon atoms. Or an unsubstituted alkyl group (2-ethylhexyl group, n-octyl group, n-decyl group, n-dodecyl group, benzyl group).

The compound represented by the general formula (102) can be synthesized by a known method described in JP-A-11-12219.
Specific examples of the compound represented by the general formula (102) are given below, but the present invention is not limited to the following specific examples.

（式中、Ｑ¹およびＱ²はそれぞれ独立に芳香族環を表す。Ｘ¹およびＸ²は水素原子または置換基を表し、少なくともどちらか１つはシアノ基、カルボニル基、スルホニル基、芳香族ヘテロ環を表す。）Ｑ¹およびＱ²で表される芳香族環は芳香族炭化水素環でも芳香族ヘテロ環でもよい。また、これらは単環であってもよいし、更に他の環と縮合環を形成してもよい。
芳香族炭化水素環として好ましくは（好ましくは炭素原子数６〜３０の単環または二環の芳香族炭化水素環（例えばベンゼン環、ナフタレン環などが挙げられる。）であり、より好ましくは炭素原子数６〜２０の芳香族炭化水素環、更に好ましくは炭素原子数６〜１２の芳香族炭化水素環である。）更に好ましくはベンゼン環である。 As the compound containing a cyano group, which is one of the wavelength dispersion adjusting agents used in the present invention, those represented by the general formula (103) are preferably used.
General formula (103)

(In the formula, Q ¹ and Q ² each independently represent an aromatic ring. X ¹ and X ² represent a hydrogen atom or a substituent, and at least one of them represents a cyano group, a carbonyl group, a sulfonyl group, an aromatic group. The aromatic ring represented by Q ¹ and Q ² may be an aromatic hydrocarbon ring or an aromatic heterocyclic ring. These may be monocyclic or may form a condensed ring with another ring.
The aromatic hydrocarbon ring is preferably (preferably a monocyclic or bicyclic aromatic hydrocarbon ring having 6 to 30 carbon atoms (for example, a benzene ring, a naphthalene ring, etc.), more preferably a carbon atom. An aromatic hydrocarbon ring having 6 to 20 carbon atoms, more preferably an aromatic hydrocarbon ring having 6 to 12 carbon atoms.) More preferably, it is a benzene ring.

  The aromatic heterocycle is preferably an aromatic heterocycle containing a nitrogen atom or a sulfur atom. Specific examples of the hetero ring include, for example, thiophene ring, imidazole ring, pyrazole ring, pyridine ring, pyrazine ring, pyridazine ring, triazole ring, triazine ring, indole ring, indazole ring, purine ring, thiazoline ring, thiazole ring, thiadiazole. Ring, oxazoline ring, oxazole ring, oxadiazole ring, quinoline ring, isoquinoline ring, phthalazine ring, naphthyridine ring, quinoxaline ring, quinazoline ring, cinnoline ring, pteridine ring, acridine ring, phenanthroline ring, phenazine ring, tetrazole ring, benz Examples include an imidazole ring, a benzoxazole ring, a benzthiazole ring, a benzotriazole ring, and a tetrazaindene ring. The aromatic hetero ring is preferably a pyridine ring, a triazine ring or a quinoline ring.

The aromatic ring represented by Q ¹ and Q ² is preferably an aromatic hydrocarbon ring, more preferably a benzene ring.
Q ¹ and Q ² may further have a substituent, and the above-described substituent T is preferable.

X ¹ and X ² each represent a hydrogen atom or a substituent, and at least one of them represents a cyano group, a carbonyl group, a sulfonyl group, or an aromatic heterocycle. The substituent T described above can be applied to the substituents represented by X ¹ and X ² . In addition, the substituent represented by X ¹ and X ² may be further substituted with another substituent, and X ¹ and X ² may each be condensed to form a ring structure.

X ¹ and X ² are preferably a hydrogen atom, an alkyl group, an aryl group, a cyano group, a nitro group, a carbonyl group, a sulfonyl group, or an aromatic heterocycle, and more preferably a cyano group, a carbonyl group, a sulfonyl group, An aromatic heterocycle, more preferably a cyano group or a carbonyl group, and particularly preferably a cyano group or an alkoxycarbonyl group (—C (═O) OR (R is an alkyl group having 1 to 20 carbon atoms, a carbon atom) 6 to 12 aryl groups and combinations thereof.

（式中、Ｒ¹、Ｒ²、Ｒ³、Ｒ⁴、Ｒ⁵、Ｒ⁶、Ｒ⁷、Ｒ⁸、Ｒ⁹およびＲ¹⁰はそれぞれ独立に水素原子または置換基を表す。Ｘ¹およびＸ²は一般式（１０３）におけるそれらと同義であり、また好ましい範囲も同様である。） Preferred as the general formula (103) is a compound represented by the following general formula (103-A).
General formula (103-A)

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ each independently represents a hydrogen atom or a substituent. X ¹ and X ² Are the same as those in formula (103), and the preferred range is also the same.)

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ each independently represents a hydrogen atom or a substituent. Is applicable. These substituents may be further substituted with another substituent, and the substituents may be condensed to form a ring structure.

R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ , and R ¹⁰ are preferably a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a substituted or unsubstituted amino group, An alkoxy group, an aryloxy group, a hydroxy group, and a halogen atom, more preferably a hydrogen atom, an alkyl group, an aryl group, an alkyloxy group, an aryloxy group, and a halogen atom, still more preferably a hydrogen atom and carbon 1-12. An alkyl group, particularly preferably a hydrogen atom or a methyl group, and most preferably a hydrogen atom.

R ³ and R ⁸ are preferably hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, substituted or unsubstituted amino groups, alkoxy groups, aryloxy groups, hydroxy groups, halogen atoms, more preferably hydrogen atoms. , An alkyl group having 1 to 20 carbon atoms, an amino group having 0 to 20 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, and a hydroxy group, more preferably hydrogen. An atom, an alkyl group having 1 to 12 carbon atoms, and an alkoxy group having 1 to 12 carbon atoms, particularly preferably a hydrogen atom.

（式中、Ｒ³およびＲ⁸は一般式（１０３-Ａ）におけるそれらと同義であり、また、好ましい範囲も同様である。Ｘ³は水素原子、または置換基を表す。）
Ｘ³は水素原子、または置換基を表し、置換基としては前述の置換基Ｔが適用でき、また、可能な場合は更に他の置換基で置換されてもよい。Ｘ³として好ましくは水素原子、アルキル基、アリール基、シアノ基、ニトロ基、カルボニル基、スルホニル基、芳香族ヘテロ環であり、より好ましくは、シアノ基、カルボニル基、スルホニル基、芳香族ヘテロ環であり、更に好ましくはシアノ基、カルボニル基であり、特に好ましくはシアノ基、アルコキシカルボニル基（-C(＝O)OR（Rは：炭素原子数１〜２０アルキル基、炭素原子数６〜１２のアリール基およびこれらを組み合せたもの）である。 More preferable as the general formula (103) is a compound represented by the following general formula (103-B).
General formula (103-B)

(Wherein R ³ and R ⁸ have the same meanings as those in formula (103-A), and preferred ranges are also the same. X ³ represents a hydrogen atom or a substituent.)
X ³ represents a hydrogen atom or a substituent. As the substituent, the above-described substituent T can be applied, and if possible, the substituent may be further substituted with another substituent. X ³ is preferably a hydrogen atom, an alkyl group, an aryl group, a cyano group, a nitro group, a carbonyl group, a sulfonyl group or an aromatic heterocyclic ring, more preferably a cyano group, a carbonyl group, a sulfonyl group or an aromatic heterocyclic ring. More preferably a cyano group or a carbonyl group, and particularly preferably a cyano group or an alkoxycarbonyl group (—C (═O) OR (R is an alkyl group having 1 to 20 carbon atoms, 6 to 12 carbon atoms). Aryl groups and combinations thereof).

（式中、Ｒ³およびＲ⁸は一般式（１０３-Ａ）におけるそれらと同義であり、また、好ましい範囲も同様である。Ｒ²¹は炭素原子数１〜２０のアルキル基を表す。） As the general formula (103), a compound represented by the general formula (103-C) is more preferable.
General formula (103-C)

(In the formula, R ³ and R ⁸ have the same meanings as those in formula (103-A), and preferred ranges are also the same. R ²¹ represents an alkyl group having 1 to 20 carbon atoms.)

R ²¹ is preferably an alkyl group having 2 to 12 carbon atoms, more preferably an alkyl group having 4 to 12 carbon atoms, and still more preferably carbon when R ³ and R ⁸ are both hydrogen. An alkyl group having 6 to 12 atoms, particularly preferably an n-octyl group, a tert-octyl group, a 2-ethylhexyl group, an n-decyl group or an n-dodecyl group, most preferably 2-ethyl Hexyl group.

R ²¹ is preferably R ³ and R ⁸ other than hydrogen, the compound represented by the general formula (103-C) has a molecular weight of 300 or more and an alkyl having 20 or less carbon atoms. Groups are preferred.

  The compound represented by the general formula (103) of the present invention can be synthesized by the method described in Journal of American Chemical Society 63, 3452 (1941).

  Specific examples of the compound represented by the general formula (103) are given below, but the present invention is not limited to the following specific examples.

[Protective film]
Moreover, it is preferable that a transparent polymer film is used as a protective film on the optically anisotropic layer side (or on both sides) of the retardation film of the present invention. That the protective film is transparent means that the light transmittance is 80% or more. As the protective film, generally a cellulose ester film, preferably a triacetyl cellulose film is used. The cellulose ester film is preferably formed by a solvent cast method. The thickness of the protective film is preferably 20 to 500 μm, and more preferably 50 to 200 μm.

[Polarizer]
A linearly polarizing film may be bonded to the retardation film of the present invention to form a polarizing plate, and then used for a liquid crystal display device. In general, a protective film is bonded to both surfaces of the polarizing film, but if the support of the retardation film of the present invention is used instead of one protective film, it contributes to thinning of the liquid crystal display device. Therefore, it is preferable. The polarizing film and the protective film for the polarizing film will be described below.
[Polarizing film]
Examples of the polarizing film include an iodine polarizing film, a dye polarizing film using a dichroic dye, and a polyene polarizing film. The iodine polarizing film and the dye polarizing film are generally produced using a polyvinyl alcohol film. The transmission axis of the polarizing film corresponds to a direction perpendicular to the stretching direction of the film. When the discotic liquid crystalline compound is used for the optically anisotropic layer, the transmission axis of the polarizing film is arranged so as to be substantially parallel to the surface of the discotic liquid crystalline compound on the alignment film side. . When a rod-like liquid crystal compound is used, it is preferable that the rod-like liquid crystal is aligned perpendicular to the polarizing film. The polarizing film is preferably bonded to the support side of the retardation film of the present invention, but may be bonded to the optically anisotropic layer side if necessary.

  The features of the present invention will be described more specifically with reference to examples and comparative examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

<Preparation of IPS mode liquid crystal cell 1>
As shown in FIG. 2, electrodes 2 and 3 are arranged on a glass substrate so that the distance between adjacent electrodes is 20 μm, and a polyimide film is provided as an alignment film thereon, and a rubbing treatment is performed. I did it. The rubbing process was performed in the direction 4 shown in FIG. A polyimide film was provided on one surface of a separately prepared glass substrate, and a rubbing treatment was performed to obtain an alignment film. The two glass substrates are stacked and bonded so that the alignment films face each other, the distance (gap; d) between the substrates is 3.9 μm, and the rubbing directions of the two glass substrates are parallel. A nematic liquid crystalline compound having a refractive index anisotropy (Δn) of 0.0769 and a dielectric anisotropy (Δε) of 4.5 was enclosed. The value of d · Δn of the liquid crystal layer was 300 nm.

[Measurement of oblique leakage light of the manufactured liquid crystal display device]
The oblique leakage light of the liquid crystal display device thus manufactured was measured. First of all, the IPS mode liquid crystal cell produced above was placed on a Schaukasten installed in a dark room without attaching a polarizing plate, and the orientation was 45 degrees to the left with respect to the rubbing direction of the liquid crystal cell. The luminance 1 was measured with a luminance meter installed at a distance of 1 m in the direction of 60 ° from the normal direction of the liquid crystal cell. Next, a liquid crystal display panel in which a polarizing plate is gradually pasted on the same Schaukasten as described above is arranged in the same manner, and the luminance 2 is similarly measured in the dark display state, and this is expressed as a percentage of the luminance 1 Was assumed to be oblique leakage light. The measured leakage light was 0.03%. Furthermore, the azimuth direction dependence of the black tint at a polar angle of 60 ° in the black display state was visually observed, but no change in tint was detected.
In addition, with respect to the measurement of the oblique leakage light of the example, a sample is placed between the liquid crystal cell and the polarizing plate on the luminance meter side, the luminance 3 is measured, and this is expressed as a percentage of the luminance 1 with the oblique leakage light. It was.

<Preparation of first retardation region 1 and first retardation region 2>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution. The solution was filtered using a filter paper (No. 63, manufactured by Advantech) having a retained particle size of 4 μm and a drainage time of 35 seconds at 0.5 MPa (5 kg / cm ² ) or less.
The cellulose acetate used here has a substitution degree of 2.86 and a 6-position substitution rate of 0.311.

────────────────────────────────────
Cellulose acetate solution composition A
────────────────────────────────────
Cellulose acetate having an acetylation degree of 60.9% (degree of polymerization: 300, Mn / Mw = 1.5) 100 parts by weight Triphenyl phosphate (plasticizer) 7.8 parts by weight Biphenyl diphenyl phosphate (plasticizer) 3.9 parts by weight Methylene chloride (first solvent) 300 parts by weight Methanol (second solvent) 54 parts by weight 1-butanol (third solvent) 11 parts by weight ──────────────────── ────────────────

  In another mixing tank, 8 parts by mass of the following retardation developer A, 10 parts by mass of retardation developer B, 0.28 parts by mass of silicon dioxide fine particles (average particle size: 0.1 μm), and 80 parts by mass of methylene chloride. And 20 parts by mass of methanol were added and stirred while heating to prepare Solution A. 40 parts by mass of the solution A was mixed with 474 parts by mass of the cellulose acetate solution, and stirred well to prepare a dope.

Retardation expression agent A

Retardation developer B

  The obtained dope was cast using a band casting machine. A film having a residual solvent amount of 15% by mass was stretched transversely at a stretch ratio of 20% using a tenter under the conditions of 130 ° C., held at 50 ° C. for 30 seconds with the stretched width, and then clipped to remove cellulose. An acetate film was prepared. The residual solvent amount at the end of stretching was 5% by mass, and further dried to prepare a film with the residual solvent amount being less than 0.1% by mass.

  The thickness of the film thus obtained (first retardation region 1) was 80 μm. About the produced 1st phase difference area | region 1, Re using the automatic birefringence meter (KOBRA-21ADH, the Oji Scientific Instruments Co., Ltd. product) measured the light incident angle dependence of Re, Re was 70 nm, Rth Was 175 nm, and it was found that Nz was 3.0.

  In another mixing tank, 16 parts by mass of the retardation developer A, 8 parts by mass of the retardation developer B, 0.28 parts by mass of silicon dioxide fine particles (average particle size: 0.1 μm), and 80 parts by mass of methylene chloride. And 20 parts by mass of methanol were added and stirred while heating to prepare solution B. 45 parts by mass of the solution B was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring to form a film in the same manner as in the first retardation region 1 described above. The thickness of the film thus obtained (first retardation region 2) was 80 μm. About the produced 1st phase difference area | region 2, Re is 60 nm by measuring the light incident angle dependence of Re using an automatic birefringence meter (KOBRA-21ADH, Oji Scientific Instruments Co., Ltd. product). It was found that Rth was 210 nm and Nz was 4.0.

<First phase difference region 3>
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution B.
The cellulose acetate used here has a substitution degree of 2.81 and a 6-position substitution rate of 0.317.

(Composition of cellulose acetate solution B)
Cellulose acetate having an acetylation degree of 60.2% 100 parts by weight Triphenyl phosphate (plasticizer) 7.8 parts by weight Biphenyl diphenyl phosphate (plasticizer) 3.9 parts by weight Methylene chloride (first solvent) 318 parts by weight Methanol (No. 2 solvents) 47 parts by mass

Into the mixing tank, 16 parts by mass of the following retardation developer C, 87 parts by mass of methylene chloride and 13 parts by mass of methanol were added and stirred while heating to prepare a retardation developer C solution.
The dope was prepared by mixing 43 parts by mass of the retardation control agent C solution with 474 parts by mass of the cellulose acetate solution composition B, and stirring sufficiently. The addition amount of the retardation developer was 6.0 parts by mass with respect to 100 parts by mass of cellulose acetate.
Retardation developer C

  After casting on a band, it was peeled off with a residual solvent amount of 32%, and then stretched in a transverse direction with a tenter stretching machine. The draw ratio was 25%, and the draw temperature was 140 ° C. Thereafter, it was dried with warm air of 130 ° C. to prepare a cellulose acetate film. The film thickness after drying was 85 μm. The obtained cellulose acetate film (first retardation region 3) was evaluated in the same manner as in the first retardation region 1. As a result, Re was 65 nm, Rth was 200 nm, and from this, it was found that Nz was 3.6. It was.

<Production of Second Phase Difference Regions 1 and 2>
The surface of each of the manufactured first retardation region 1 and first retardation region 2 was subjected to saponification treatment, and an alignment film coating solution having the following composition was applied onto this film with a wire bar coater at 20 ml / m ² . . A film was formed by drying with warm air of 60 ° C. for 60 seconds and further with warm air of 100 ° C. for 120 seconds to obtain an alignment film.
Composition of alignment film coating solution Modified polyvinyl alcohol 10 parts by weight Water 371 parts by weight Methanol 119 parts by weight Glutaraldehyde 0.5 parts by weight

  Next, 2.0 g of the following rod-like liquid crystal compound, 0.06 g of photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals), sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) A solution was prepared by dissolving 0.02 g, the following onium salt, 0.02 g for each, and 0.002 g of the following air interface side vertical alignment agent in 2.7 g of methyl ethyl ketone. This coating solution was applied to the surface of the alignment film by adjusting the coating film thickness with a wire bar. This was affixed to a metal frame and heated in a thermostatic bath at 80 ° C. for 2 minutes to align the rod-like liquid crystal compound. Next, UV irradiation is performed at 60 ° C. with a 120 W / cm high-pressure mercury lamp for 20 seconds to crosslink the rod-like liquid crystal compound, and then the mixture is allowed to cool to room temperature to produce second retardation regions 1 and 2. And 2. At this time, when the optically anisotropic layer was produced with the same conditions except for the temperature during UV irradiation and the temperatures during UV irradiation being 30 ° C. and 100 ° C., an alignment defect occurred on one surface, which was used as the second retardation region. could not. The optical characteristics of the optically anisotropic layer are shown in Table 1. Table 2 shows combinations of the first phase difference region and the second phase difference region.

<Preparation of Second Phase Difference Region 3>
For the manufactured first retardation region 3, a saponification treatment and an alignment film were formed in the same manner as when the first retardation region 1 was produced.

Next, 2.0 g of the above rod-shaped liquid crystal compound, 0.06 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals Co., Ltd.), sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 0 0.02 g, 0.02 g of the following onium salt, 0.004 g of the following air interface side vertical alignment agent, and 0.1 g of UV curable resin (KAYARAD DPHA, Nippon Kayaku Co., Ltd.) are dissolved in 3.9 g of methyl ethyl ketone. A prepared solution was prepared. This coating solution was applied to the surface of the alignment film by adjusting the coating film thickness with a wire bar. This was affixed to a metal frame and heated in a constant temperature bath at 70 ° C. for 1 minute 30 seconds to align the rod-like liquid crystal compound. Next, while keeping the temperature at 70 ° C., irradiation with ultraviolet light having an illuminance of 400 mW / cm ² and an irradiation amount of 600 mJ / cm ² is performed using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under nitrogen purge. Then, the rod-like liquid crystal compound was crosslinked, and then allowed to cool to room temperature, whereby the second retardation region 3 was produced, and the retardation film 3 was obtained. The optical characteristics of the optically anisotropic layer are shown in Table 1. Table 2 shows combinations of the first phase difference region and the second phase difference region.

<Production of Polarizing Plate Protective Film 1>
The following composition was put into a mixing tank, stirred while heating to dissolve each component, and a cellulose acetate solution C was prepared.
<Cellulose acetate solution C composition>
Cellulose acetate with a substitution degree of 2.86 100 parts by weight Triphenyl phosphate (plasticizer) 7.8 parts by weight Biphenyl diphenyl phosphate (plasticizer) 3.9 parts by weight Methylene chloride (first solvent) 300 parts by weight Methanol (second solvent) 54 parts by weight 1-butanol 11 parts by weight

The following composition was charged into another mixing tank, stirred while heating to dissolve each component, and an additive solution B-1 was prepared.
<Additive solution B-1 composition>
Methylene chloride 80 parts by mass Methanol 20 parts by mass The following retardation reducing agent 40 parts by mass

40 parts by mass of the additive solution B-1 was added to 477 parts by mass of the cellulose acetate solution A, and the dope was prepared by sufficiently stirring. The dope was cast from a casting port onto a drum cooled to 0 ° C. The film is peeled off at a solvent content of 70% by mass, and both ends in the width direction of the film are fixed with a pin tenter (the pin tenter described in FIG. 3 of JP-A-4-1009), and the solvent content is 3-5% by mass. In this state, the film was dried while maintaining an interval at which the stretching ratio in the transverse direction (direction perpendicular to the machine direction) was 3%. Then, it further dried by conveying between the rolls of the heat processing apparatus, and produced the polarizing plate protective film 1 with a thickness of 80 μm.
Using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments Co., Ltd.), the light incident angle dependence of Re was measured, and the optical characteristics were calculated. Re was 1 nm and Rth was 6 nm. I was able to confirm.
In addition, | Re ₍₄₀₀₎ −Re ₍₇₀₀₎ | was 6 nm, and | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | was 20 nm.

<Preparation of polarizing plate protective film 2>
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a cellulose acetate solution D.
Composition of cellulose acetate solution D ――――――――――――――――――――――――――――――――――――
Cellulose acetate with an acetyl substitution degree of 2.94 100.0 parts by mass Methylene chloride (first solvent) 402.0 parts by mass Methanol (second solvent) 60.0 parts by mass ――――――――――――― ――――――――――――――――――――――

(Preparation of matting agent solution)
20 parts by mass of silica particles having an average particle diameter of 16 nm (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) and 80 parts by mass of methanol were mixed well for 30 minutes to obtain a silica particle dispersion. This dispersion was put into a disperser together with the following composition, and further stirred for 30 minutes or more to dissolve each component to prepare a matting agent solution.
Matting agent solution composition ――――――――――――――――――――――――――――――――――
Silica particle dispersion with an average particle size of 16 nm 10.0 parts by weight Methylene chloride (first solvent) 76.3 parts by weight Methanol (second solvent) 3.4 parts by weight Cellulose acetate solution D 10.3 parts by weight ―――――――――――――――――――――――――――――

(Preparation of additive solution)
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare an additive solution.
Additive solution composition ――――――――――――――――――――――――――――――
49.3 parts by mass of the retardation reducing agent 4.9 parts by mass of the following wavelength dispersion adjusting agent 4.9 parts by mass of methylene chloride (first solvent) 8.7 parts by mass of methanol (second solvent) 8.7 parts by mass of cellulose acetate solution D 12 .8 parts by mass ――――――――――――――――――――――――――――――

(Production of cellulose acetate film)
94.6 parts by mass of the cellulose acetate solution D, 1.3 parts by mass of the matting agent solution, and 4.1 parts by mass of the additive solution were mixed after filtration, and cast using a band casting machine. In the above composition, the mass ratios of the retardation reducing agent and the wavelength dispersion adjusting agent to cellulose acetate were 12% and 1.2%, respectively. The film was peeled from the band with a residual solvent amount of 30% and dried at 140 ° C. for 40 minutes to produce a long cellulose acetate film having a thickness of 80 μm. The obtained film had an in-plane retardation (Re) of 1 nm and a thickness direction retardation (Rth) of 3 nm.
Moreover, | Re ₍₄₀₀₎ −Re ₍₇₀₀₎ | was 4 nm, and | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | was 12 nm.

<Production of Polarizing Plate Protective Film 3>
In the same manner as the polarizing plate protective film 2, the cast film thickness was adjusted to produce a long cellulose acetate film having a thickness of 35 μm. The obtained film had an in-plane retardation (Re) of 0 nm and a thickness direction retardation (Rth) of 0 nm.
In addition, | Re ₍₄₀₀₎ −Re ₍₇₀₀₎ | was 2 nm, and | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | was 6 nm.

<Preparation of polarizing plate A>
Next, iodine is adsorbed on the stretched polyvinyl alcohol film to produce a polarizing film, and a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd., Re = 3 nm, Rth = 45 nm) is subjected to saponification treatment. A polarizing plate A was formed on one surface of the polarizing film using a polyvinyl alcohol adhesive.

<Preparation of polarizing plate B>
A polarizing film is produced by adsorbing iodine to a stretched polyvinyl alcohol film, and a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) is subjected to saponification treatment, using a polyvinyl alcohol adhesive, A polarizing plate B was formed on both sides of the polarizing film.

<Preparation of polarizing plate C>
A polarizing film was produced in the same manner, and a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was saponified and attached to one side of the polarizing film using a polyvinyl alcohol-based adhesive. . In the same manner, the polarizing plate protective film 1 manufactured as described above was attached to the other side of the polarizing film to form a polarizing plate C.

<Preparation of polarizing plate D>
A polarizing film was produced in the same manner, and a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was saponified and attached to one side of the polarizing film using a polyvinyl alcohol-based adhesive. . In the same manner, a commercially available cellulose acetate film (Fujitac T40UZ, manufactured by Fuji Photo Film Co., Ltd., Re = 1 nm, Rth = 35 nm) was saponified, and the other side of the polarizing film was coated with a polyvinyl alcohol adhesive. A pasting polarizing plate D was formed.

<Preparation of polarizing plate E>
A polarizing film was produced in the same manner, and a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was saponified and attached to one side of the polarizing film using a polyvinyl alcohol-based adhesive. . Further, similarly, the polarizing plate protective film 2 manufactured as described above was attached to the other surface of the polarizing film to form a polarizing plate E.

<Preparation of polarizing plate F>
A polarizing film was produced in the same manner, and a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was saponified and attached to one side of the polarizing film using a polyvinyl alcohol-based adhesive. . Further, similarly, the polarizing plate protective film 3 manufactured as described above was attached to the other surface of the polarizing film to form a polarizing plate F.

[Comparative Example 1] (Example without a retardation film)
The polarizing plate B was attached to one side of the IPS mode liquid crystal cell 1 produced above so that the absorption axis of the polarizing film was parallel to the rubbing direction of the liquid crystal cell. Subsequently, a polarizing plate B was attached to the other side of the liquid crystal cell 1 so that the absorption axis of the polarizing film was perpendicular to the rubbing direction of the liquid crystal cell. The front contrast at this time is 400, which is larger than when the phase difference of the embodiment is provided, but the oblique leakage light when the panel is observed from a polar angle of 60 ° and an azimuth angle of 45 ° when displaying black is 0.58. It was not effective.

[Comparative Example 2] (Example not satisfying formula 0.000 <A = (L−X) / d <2.5)
After saponifying the surface of a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.), an alignment film coating solution having the following composition was applied onto the film with a wire bar coater at 20 ml / m ² . The film was formed by drying with warm air of 60 ° C. for 60 seconds and further with warm air of 100 ° C. for 120 seconds. Next, the formed film was rubbed in a direction parallel to the slow axis direction of the film to form an alignment film.
Composition of alignment film coating solution ―――――――――――――――――――――――――――――――――――
Denatured polyvinyl alcohol 10 parts by weight Water 371 parts by weight Methanol 119 parts by weight Glutaraldehyde 0.5 parts by weight Compound B 0.2 parts by weight ―――――――――――――――――――― ―――――――――――――――

Next, on the alignment film rubbed with each strength, a coating solution having the following composition was applied with a wire bar so that the front retardation after curing was 122 nm.
―――――――――――――――――――――――――――――――――――
Discotic liquid crystal compound 1.8g
Ethylene oxide modified trimethylolpropane triacrylate (V # 360, manufactured by Osaka Organic Chemical Co., Ltd.) 0.2 g
Photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) 0.06 g
Sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 0.02g
Air interface side alignment agent (compound A below) 0.01 g
Methyl ethyl ketone 3.9g
―――――――――――――――――――――――――――――――――――
This was affixed to a metal frame and heated in a thermostatic bath at 125 ° C. for 3 minutes to align the discotic liquid crystal compound. Next, using a 120 W / cm high-pressure mercury lamp, UV irradiation was performed for 30 seconds to crosslink the discotic liquid crystal compound. The temperature at the time of UV curing was set to 80 ° C. to obtain a retardation film. Then, it stood to cool to room temperature. In this way, the retardation film 4 was manufactured.

  Using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments Co., Ltd.), the light incident angle dependency of Re of the retardation film 4 was measured, and the cellulose acetate film (Re = 5 nm) measured in advance. The optical characteristics of only the discotic liquid crystalline phase difference layer were calculated by subtracting the contribution of. The front Re was 122 nm. The Re of the entire optical compensation sheet was 127 nm. Further, the tilt angle of the liquid crystal was 90.0 °, and it was confirmed that the optical axis of the discotic liquid crystalline compound was aligned in parallel to the substrate with respect to the film surface. The slow axis direction was parallel to the rubbing direction of the alignment film.

  A polarizing film was produced by adsorbing iodine to a stretched polyvinyl alcohol film. Using the polyvinyl alcohol adhesive, the produced retardation film 4 was affixed on one side of the polarizing film so that the cellulose acetate film was on the polarizing film side. The transmission axis of the polarizing film and the slow axis of the optical compensation film (the slow axis of the second retardation region also coincides with this) were arranged in parallel. A commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was subjected to saponification treatment and attached to the opposite side of the polarizing film using a polyvinyl alcohol adhesive. This is applied to one of the IPS mode liquid crystal cells 1 produced above so that the slow axis of the retardation film 4 is parallel to the rubbing direction of the liquid crystal cell (that is, the slow axis of the second retardation region is It was attached so that the slow axis of the liquid crystal compound of the liquid crystal cell during black display was parallel) and the discotic liquid crystal application surface side was the liquid crystal cell side. Then, the polarizing plate B was affixed on the other side of the IPS mode liquid crystal cell 1 in a crossed Nicol arrangement to produce a liquid crystal display device 2.

At this time, A in the formula A = (L / X) / d is 3.86, and the oblique leakage light when the panel is observed from a polar angle of 60 ° and an azimuth angle of 45 ° when displaying black is 0.16%. However, the front contrast was greatly reduced to 302.

[Example 1]
Using a polyvinyl alcohol-based adhesive for the polarizing plate A, the retardation film 1 produced as described above is arranged such that the first retardation region 1 side is the first polarizing film side and the transmission axis of the first polarizing film is A polarizing plate 1 was formed on the side of the first polarizing film where the cellulose acetate film was not bonded so that the slow axis of the one retardation region 1 was parallel.

This is applied to one of the IPS mode liquid crystal cells 1 produced above so that the slow axis of the first retardation region 1 is parallel to the rubbing direction of the liquid crystal cell (that is, the slow phase of the first retardation region 1). The polarizing plate 1 was attached so that the axis was parallel to the slow axis of the liquid crystal compound of the liquid crystal cell during black display) and the second retardation region 1 surface side was on the liquid crystal cell side.
Subsequently, the polarizing plate C is pasted on the other side of the IPS mode liquid crystal cell 1 so that the polarizing plate protective film 1 side is on the liquid crystal cell side and in a crossed Nicol arrangement with the polarizing plate 1. A liquid crystal display device was produced. The retardation film had A = 0.59. The front contrast of the liquid crystal display device thus fabricated was 384. Further, the oblique leakage light when the panel was observed from a polar angle direction of 60 ° and an azimuth angle direction of 45 ° during black display was as small as 0.12%.

[Example 2]
Using the polyvinyl alcohol-based adhesive for the polarizing plate A, the retardation film 2 produced as described above is arranged such that the first retardation region 1 side is the polarizing film side and the transmission axis of the polarizing film and the first retardation region A polarizing plate 2 was formed on the side where the cellulose acetate film of the first polarizing film was not bonded so that the slow axis of 1 was parallel.

This is applied to one of the IPS mode liquid crystal cells 1 produced above so that the slow axis of the first retardation region 2 is parallel to the rubbing direction of the liquid crystal cell (that is, the slow phase of the first retardation region 2). The polarizing plate 2 was attached so that the axis was parallel to the slow axis of the liquid crystalline compound of the liquid crystal cell during black display) and the second retardation region 2 surface side was on the liquid crystal cell side.
Subsequently, the polarizing plate D is attached to the other side of the IPS mode liquid crystal cell 1 so that the T40UZ side is on the liquid crystal cell side and the polarizing plate 2 is in a crossed Nicol arrangement. Produced. The retardation film was A = 0.61. The front contrast of the liquid crystal display device thus fabricated was 388. Further, the oblique leakage light when observed from the polar angle direction of 60 ° and the azimuth angle direction of 45 ° when the panel displayed black was as small as 0.06%.

[Example 3]
Using a polyvinyl alcohol-based adhesive for the polarizing plate A, the retardation film 3 produced as described above is arranged such that the first retardation region 3 side is the polarizing film side, and the transmission axis of the polarizing film and the first retardation region are A polarizing plate 3 was formed by pasting the polarizing film on the side where the cellulose acetate film was not pasted so that the slow axis of 3 was parallel.

This is applied to one of the IPS mode liquid crystal cells 1 produced above so that the slow axis of the first retardation region 3 is parallel to the rubbing direction of the liquid crystal cell (that is, the slow phase of the first retardation region 1). The polarizing plate 3 was affixed so that the axis was parallel to the slow axis of the liquid crystal compound of the liquid crystal cell during black display) and the second retardation region 3 surface side was on the liquid crystal cell side.
Subsequently, the polarizing plate E is pasted on the other side of the IPS mode liquid crystal cell 1 so that the polarizing plate protective film 2 side is on the liquid crystal cell side and in a crossed Nicol arrangement with the polarizing plate 1. A liquid crystal display device was produced. The retardation film had A = 0.57. The front contrast of the liquid crystal display device thus fabricated was 390. Further, the oblique leakage light when the panel was observed from the polar angle direction 60 ° and the azimuth angle direction 45 ° when displaying black was as small as 0.05%.

[Example 4]
A liquid crystal display device was produced in the same manner as in Example 3 except that the polarizing plate E was replaced with the polarizing plate F. The retardation film was A = 0.010. The front contrast of the liquid crystal display device thus fabricated was 395. Further, the oblique leakage light when observed from the polar angle direction of 60 ° and the azimuth angle direction of 45 ° when the panel displayed black was as small as 0.03%.

Table 3 shows a summary of the evaluation.

It is a schematic model diagram of an apparatus for measuring the front luminance of the retardation film. It is the schematic which shows the pixel area example of the liquid crystal display device of this invention. It is the schematic which shows the example of the liquid crystal display device of this invention. It is the schematic which shows the example of the liquid crystal display device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal element pixel area 2 Pixel electrode 3 Display electrode 4 Rubbing direction 5a, 5b Director of liquid crystal compound at the time of black display 6a, 6b Director of liquid crystal compound at the time of white display 7a, 7b First polarizing plate protective film 8 First Polarizing film 9 Polarization transmission axis 10 of first polarizing film Retardation film 11 First retardation region (transparent support)
12 Second retardation region (optically anisotropic layer)
13 Slow axis 14 of first retardation region 1st substrate 15 First substrate rubbing direction 16 Liquid crystal layer 17 Slow axis direction 18 of liquid crystal compound Second substrate 19 Second substrate rubbing directions 20a, 20b Protection of second polarizing plate Film 21 second polarizing film 22 second polarizing film polarization transmission axis

Claims (15)

An optically anisotropic film containing a liquid crystalline compound, wherein the frontal Re of the optically anisotropic film is 0 to 20 nm, and the optically anisotropic film is in a crossed Nicol state when a diffusion light source is used. An optically anisotropic film satisfying the following formula, where L (cd / m ² ) is the front leakage light when it is disposed between two polarizing plates.
Formula 0.00 <A <2.50
A = (L / X) / d
(Where X represents front leakage light (cd / m ² ) when two polarizing plates are placed in a crossed Nicols state without an optically anisotropic film, and d represents the film thickness of the optically anisotropic film ( In addition, the polarizing plate used for leakage light measurement is 0.00000 <X / M <0.00010, and M represents the front luminance (cd / m ² ) of the light source for leakage light measurement.) A retardation film comprising the optically anisotropic film according to claim 1 and having a front Re of 0 to 200 nm. The retardation film according to claim 2, wherein the liquid crystal compound is a rod-like liquid crystal compound having a polymerizable group. 4. The method for producing a retardation film according to claim 3, wherein the rod-like liquid crystal compound having the polymerizable group is aligned so that its optical axis is perpendicular to a substrate plane, and then the polymerizable property is obtained. A production method comprising a step of polymerizing a group in a range of 40 ° C. to 80 ° C. and fixing the group in an orientation state to form an optically anisotropic film. At least a first polarizing film, a first retardation region, a second retardation region, and a liquid crystal cell having a liquid crystal layer sandwiched between a pair of substrates. A liquid crystal display device oriented substantially parallel to the surface of the substrate,
The Re (λ) of the first retardation region is 20 nm to 150 nm, and the Nz value of the first retardation region defined by Nz = Rth / Re + 0.5 is 1.5 to 7, 4. The Re (λ) of the second retardation region is 5 nm or less, the Rth (λ) of the second retardation region is −80 nm to −400 nm, and the liquid crystal display device according to claim 2 or 3. (However, the retardation film may be included in the first retardation region or the second retardation region), and the molecules of the rod-like liquid crystalline compound are contained in the retardation film. A liquid crystal display device which is substantially vertically aligned and further has a transmission axis of the first polarizing film parallel to a slow axis direction of a liquid crystal compound during black display of the liquid crystal layer. And a second polarizing film having a transmission axis perpendicular to the transmission axis of the first polarizing film, wherein the first polarizing film and the second polarizing film are the first retardation region, the second retardation region, and The liquid crystal display device according to claim 5, wherein the liquid crystal cell is sandwiched and disposed. The first polarizing film, the first retardation region, the second retardation region, and the liquid crystal cell are arranged in this order, and the slow axis of the first retardation region is that of the first polarizing film. The liquid crystal display device according to claim 5, wherein the liquid crystal display device is substantially parallel to the transmission axis. The liquid crystal display device according to claim 5, wherein the first retardation region is made of a polymer film that exhibits optical anisotropy by stretching. The first retardation region is a polymer film containing a cellulose acylate obtained by substituting a hydroxyl group of a glucose unit constituting cellulose with an acyl group having 2 or more carbon atoms. When the substitution degree of the hydroxyl group with an acyl group is DS ² , the substitution degree of the hydroxyl group at the 3-position with DS ³ , and the substitution degree with the acyl group of the hydroxyl group at the 6-position is DS ⁶ , the following formulas (I) and ( The liquid crystal display device according to claim 5, which satisfies II).
(I): 2.0 ≦ DS ² + DS ³ + DS ⁶ ≦ 3.0
(II): DS ⁶ / (DS ² + DS ³ + DS ⁶ ) ≧ 0.315 10. The liquid crystal display device according to claim 8, wherein the polymer film contains at least one retardation developer composed of a rod-shaped compound or a disk-shaped compound. A protective film is provided on a side closer to the liquid crystal layer of the first polarizing film and / or the second polarizing film, and the thickness direction retardation Rth of the protective film is in the range of -40 to 40 nm. The liquid crystal display device according to any one of 10. The protective film is provided in the side near the liquid crystal layer of the 1st polarizing film and / or the 2nd polarizing film, and the thickness of this protective film is 60 micrometers or less. Liquid crystal display device. The protective film is provided in the side near the liquid crystal layer of the first polarizing film and / or the second polarizing film, and the protective film is a cellulose acylate film or a norbornene-based film. A liquid crystal display device according to item. A protective film is provided on a side close to the liquid crystal layer of the first polarizing film and / or the second polarizing film, and the protective film is a cellulose acylate film satisfying the following formulas (III) and (IV): Item 14. The liquid crystal display device according to any one of items 6 to 13.
(III) 0 ≦ Re ₍₆₃₀₎ ≦ 10 and | Rth ₍₆₃₀₎ | ≦ 25
(IV) | Re ₍₄₀₀₎ −Re ₍₇₀₀₎ | ≦ 10 and | Rth ₍₄₀₀₎ −Rth ₍₇₀₀₎ | ≦ 35 A protective film is provided on the first polarizing film and / or the second polarizing film on the side close to the liquid crystal layer, the protective film is a cellulose acylate film, and the cellulose acylate film has an acyl substitution degree of 2. To a cellulose acylate of 85 to 3.00, at least one compound that reduces Re (λ) and Rth (λ) is added at a ratio of 0.01 to 30% by mass with respect to the cellulose acylate. The liquid crystal display device according to claim 6, which is obtained.

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