JP2008052267A - Optical compensation film, its manufacturing method, polarizing plate, and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device, particularly the liquid crystal display devices of VA, IPS and OCB modes capable of reducing coloring in a viewing angle direction by precisely performing optical compensation not only in the front direction but also in oblique directions. <P>SOLUTION: The optical compensation film or the like includes a transparent support containing at least one kind of Rth raising agent. In the transparent support, the degree of orientation P defined by an expression (A), P=<3cos<SP>2</SP>β-1>/2, calculated by x-ray diffraction measurement is within 0.05 to 0.30, where <cos<SP>2</SP>β>=∫(0, π)cos<SP>2</SP>βI(β)sinβdβ/∫(0, π)I(β)sinβdβ is satisfied. In the expression, β is an angle defined by an incident plane of the incident X-ray and one direction in a surface of the transparent support, and I is diffraction intensity at 2θ=8° in an X-ray diffraction chart measured at the angle β. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical compensation film, a manufacturing method thereof, a polarizing plate, and a liquid crystal display device.

The liquid crystal display device has a liquid crystal cell and a polarizing plate. The polarizing plate generally has a protective film and a polarizing film made of cellulose acetate. For example, a polarizing film made of a polyvinyl alcohol film is dyed with iodine, stretched, and both surfaces thereof are laminated with a protective film. Obtained.
In the transmissive liquid crystal display device, polarizing plates are attached to both sides of the liquid crystal cell, and one or more optical compensation films may be disposed.
In a reflective liquid crystal display device, usually, a reflector, a liquid crystal cell, one or more optical compensation films, and a polarizing plate are arranged in this order.
The liquid crystal cell includes a liquid crystal molecule, two substrates for encapsulating the liquid crystal molecule, and an electrode layer for applying a voltage to the liquid crystal molecule.
The liquid crystal cell performs ON / OFF display depending on the alignment state of liquid crystal molecules, and can be applied to both transmission and reflection types. TN (Twisted Nematic), IPS (In-Plane Switching), OCB (Optically Compensatory Bend). ), VA (Vertically Aligned), and ECB (Electrically Controlled Birefringence) have been proposed.

Among such liquid crystal display devices, for applications that require high display quality, nematic liquid crystal molecules having a positive dielectric anisotropy are used, and a 90 ° twisted nematic liquid crystal display device (hereinafter referred to as a thin film transistor) is driven. TN mode) is mainly used.
However, although the TN mode has excellent display characteristics when viewed from the front, the contrast is lowered when viewed from an oblique direction, and display is caused by gradation inversion in which the brightness is reversed in gradation display. There is a viewing angle characteristic that the characteristic is deteriorated, and this improvement is strongly desired.

On the other hand, the liquid crystal systems having a wide viewing angle such as the IPS system, the OCB system, and the VA system have expanded their share with the recent increase in demand for liquid crystal televisions.
However, although each system has improved display quality year by year (Patent Documents 1 to 14), the problem of color misregistration that occurs when viewed obliquely has not been solved.

It has been found that the cause of this color shift is due to the wavelength dispersion between the optical compensation film Re and Rth. In particular, in the case of Re, “reverse dispersion” in which the Re value monotonously increases as the wavelength becomes longer, and in the case of Rth, the color becomes “forward dispersion” in which the Re value monotonously decreases as the wavelength becomes longer. The taste is neutral, and the effect of changing the viewing angle is small.
However, since it is difficult to obtain an optical compensation film having such characteristics with a single sheet, conventionally, wavelength dispersion characteristics are realized using two optical compensation films.
However, when two optical compensation films are used, the thickness of the polarizing plate to which the film is applied increases. In addition, since this leads to an increase in cost, it has been desired that Re be set to “reverse dispersion” and Rth be set to “forward dispersion” with a single optical compensation film.

JP-A-9-212444 JP 11-316378 A Japanese Patent Laid-Open No. 2-176625 JP-A-11-95208 JP 2003-15134 A JP-A-11-95208 Japanese Patent Laid-Open No. 2002-221622 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 JP 11-133408 A JP-A-11-305217 JP-A-10-307291

  The present invention aims to solve the above-described problems and achieve the following objects. In other words, liquid crystal display devices that can reduce tinting in the viewing angle direction by strictly performing optical compensation not only in the front direction but also in an oblique direction with a single optical compensation film, particularly in VA, IPS, and OCB modes. An object is to provide a liquid crystal display device.

  The present invention accurately compensates a liquid crystal cell optically, and improves the color shift depending on the viewing angle direction at the time of high contrast and black display by one sheet, particularly for VA, IPS and OCB modes. In order to obtain a compensation film, a method for producing the same, and a polarizing plate using the compensation film, the present inventors have intensively studied to achieve this.

Means for solving the above-mentioned problems are as follows. That is,
<1> It has a transparent support containing at least one Rth increasing agent, and the degree of orientation P defined by the following formula (A) calculated from the X-ray diffraction measurement with respect to the transparent support is 0.00. It is an optical compensation film characterized by being from 0.5 to 0.30.
P = <3cos ² β-1> / 2... Formula (A)
However, in the above formula (A), <cos ² β> = ∫ (0, π) cos ² βI (β) sinβdβ / ∫ (0, π) I (β) sinβdβ.
In the above formula, β is an angle formed by the incident surface of the incident X-ray and a certain direction in the surface of the transparent support, and I is 2θ = 8 in the X-ray diffraction chart measured at the angle β. It is the diffraction intensity at °.
<2> The optical compensation film according to <1>, wherein the optical properties of one transparent support satisfy the relationships of the following formulas (1) to (6).
10 nm <Re ₍₅₅₀₎ <100 nm... Formula (1)
100 nm <Rth ₍₅₅₀₎ <200 nm (2)
0.5 <Re ₍₄₅₀₎ / Re ₍₅₅₀₎ <1.0 (3)
1.0 <Re ₍₆₃₀₎ / Re ₍₅₅₀₎ <1.5... Equation (4)
1.0 <Rth ₍₄₅₀₎ / Rth ₍₅₅₀₎ <1.5... Formula (5)
0.5 <Rth ₍₆₃₀₎ / Rth ₍₅₅₀₎ <1.0 ... Formula (6)
In the above formulas (1) to (6), Re _(λ) is the retardation value of the transparent support for light with a wavelength of _λ nm, and Rth _(λ) is the transparent support for light with a wavelength of _λ nm. It is the retardation value in the thickness direction of the body.
<3> The optical compensation film according to any one of <1> to <2>, wherein the Rth increasing agent is a compound represented by any one of the following general formulas (II) to (V).
However, in the following general formula (II), each R ¹² independently represents an aromatic ring or a heterocyclic ring having a substituent in at least one of the ortho position, the meta position and the para position.
Moreover, X < ¹¹ > represents a single bond or NR < ¹³ >-each independently. Here, each R ¹³ independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an aryl group, or a heterocyclic group.
Moreover, in the following general formula (III), R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ each independently represent a hydrogen atom or a substituent.
In the following general formula (IV), Q ⁷¹ represents a nitrogen-containing aromatic heterocycle, and Q ⁷² represents an aromatic ring.
Further, in the following general formula ^{(V), Q 81} and ^{Q 82} represents an aromatic ring each ^{independently, X 81} is ^NR 81 ^{(R 81} represents a hydrogen atom or a substituent) represents an oxygen atom or a sulfur atom Represents.
<4> The optical compensation film according to any one of <1> to <3>, wherein the Rth increasing agent has two or more aromatic rings.
<5> The optical compensation film according to any one of <1> to <4>, including a compound having a maximum absorption wavelength (λ _max ) of at least 250 nm in a solution absorption spectrum of the Rth increasing agent.
<6> The optical compensation film according to any one of <1> to <5>, wherein a humidity dependency improving agent having a hydrogen bonding group in at least one molecule is contained.
<7> The optical compensation film according to <6>, wherein the humidity dependency improving agent has an aromatic ring and satisfies the following formula (7).
Molecular weight of the number of hydrogen bonding groups in one molecule / humidity dependency improver ≧ 0.01 (7)
<8> The optical compensation film according to any one of <1> to <7>, wherein the transparent support is a cellulose acylate film satisfying the following formulas (8) to (9).
2.0 ≤ SA + SB ≤ 3.0 ........................... (8)
0 <SB ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Equation (9)
However, in said formula (8)-(9), SA is the substitution degree of the acetyl group which has substituted the hydrogen atom of the hydroxyl group in a cellulose, SB substituted the hydrogen atom of the hydroxyl group in a cellulose. The substitution degree of the acyl group having 3 to 22 carbon atoms.
<9> The method for producing an optical compensation film according to any one of <1> to <8>, wherein a polymer solution, which is a raw material for a transparent support containing at least one Rth increasing agent, is allowed to flow over the band. A casting process, a drying process for drying the film produced by the casting process, and after peeling the film from the band, at a temperature of +15 to + 100 ° C. than the glass transition temperature of the transparent support. And a stretching step of stretching the film.
<10> The drying step is the method for producing an optical compensation film according to <9>, wherein an average drying rate for a region where the volatile content of the film is 10 to 100% by mass is at least 1.2% by mass / min. is there.
<11> A polarizing plate having a polarizing film and a pair of protective films sandwiching the polarizing film, wherein at least one of the protective films is the optical according to any one of <1> to <8> The polarizing plate is a compensation film.
<12> The above-mentioned <11, which has a coating layer having low moisture permeability on at least one surface of the protective film, and has a moisture permeability of 300 g / m ² · day or less at 60 ° C. and 95% relative humidity. > Polarizing plate.
<13> A liquid crystal display device comprising a liquid crystal cell and the polarizing plate according to any one of <11> to <12>.
<14> The liquid crystal display device according to <13>, wherein the liquid crystal cell is a VA method, an OCB method, or an IPS method.

According to the present invention, not only the front surface but also the optical compensation film in the oblique direction can be reduced with a single optical compensation film, thereby reducing the coloring in the viewing angle direction, particularly VA, IPS, And an optical compensation film for OCB mode, and a polarizing plate using the same.
In addition, according to the present invention, a liquid crystal display device that can reduce tinting in the viewing angle direction by strictly performing optical compensation not only in the front but also in an oblique direction, particularly a liquid crystal display device in VA, IPS, and OCB modes. Can be provided.

Hereinafter, the optical compensation film, the polarizing plate, and the liquid crystal display device according to the present invention will be described in detail.
In the description of the present embodiment, “45 °”, “parallel” or “orthogonal” means that the angle is within a range of strictly less than ± 5 °. The error from the exact angle is preferably less than 4 °, more preferably less than 3 °. Regarding the angle, “+” means the clockwise direction, and “−” means the counterclockwise direction. Further, the “slow axis” means a direction in which the refractive index is maximized. The “visible light region” means 380 to 780 nm. Further, the refractive index measurement wavelength is a value in the visible light region (λ = 550 nm) unless otherwise specified.

In the description of the present embodiment, the term “polarizing plate” is used to include both a long polarizing plate and a polarizing plate cut into a size incorporated in a liquid crystal device unless otherwise specified. Yes. Here, “cutting” includes “punching” and “cutting out”.
In the description of the present embodiment, “polarizing film” and “polarizing plate” are distinguished from each other. However, “polarizing plate” is a laminate having a transparent protective film that protects the polarizing film on at least one side of “polarizing film”. It shall mean the body.

In the description of the present embodiment, the “molecular symmetry axis” refers to a symmetry axis when the molecule has a rotational symmetry axis, but strictly requires that the molecule is rotationally symmetric. is not.
In general, in a discotic liquid crystalline compound, the molecular symmetry axis coincides with an axis perpendicular to the disc surface passing through the center of the disc surface, and in a rod-like liquid crystalline compound, the molecular symmetry axis is the major axis of the molecule. Match.

In the present specification, Re _(λ) and Rth _(λ) represent in-plane retardation and retardation in the thickness direction at the wavelength λ, respectively. Re _(λ) is measured with KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments) by allowing light of wavelength λ nm to be incident in the normal direction of the film.
When the film to be measured is represented by a uniaxial or biaxial refractive index ellipsoid, Rth _(λ) is calculated by the following method.
Rth _(λ) is the film surface when Re _(λ) is used and the in-plane slow axis (determined by KOBRA 21ADH or WR) is the tilt axis (rotation axis) (if there is no slow axis) Measurement is performed at a total of 6 points by injecting light of wavelength λ nm from each inclined direction in steps of 10 degrees from the normal direction to 50 ° on one side with respect to the film normal direction (with any rotation direction as the rotation axis). Then, KOBRA 21ADH or WR is calculated based on the measured retardation value, the assumed value of the average refractive index, and the input film thickness value.
In the above case, in the case of a film having a direction in which the retardation value is zero at a certain tilt angle with the in-plane slow axis from the normal direction as the rotation axis, retardation at a tilt angle larger than the tilt angle. The value is calculated by KOBRA 21ADH or WR after changing its sign to negative.
The retardation value is measured from two inclined directions with the slow axis as the tilt axis (rotation axis) (if there is no slow axis, the arbitrary direction in the film plane is the rotation axis). Rth can also be calculated from the following formula (B) and formula (C) based on the value, the assumed value of the average refractive index, and the input film thickness value.

・ ・ ・ ・ ・ ・ Formula (B)

Note that Re (θ) represents a retardation value in a direction inclined by an angle θ from the normal direction.
In the formula (B), nx represents the refractive index in the slow axis direction in the plane, ny represents the refractive index in the direction orthogonal to nx in the plane, and nz represents the refraction in the direction orthogonal to nx and ny. Represents a rate.

Rth = ((nx + ny) / 2−nz) × d (Equation (C)

When the film to be measured is a film that cannot be expressed by a uniaxial or biaxial refractive index ellipsoid, that is, a film without a so-called optical axis, Rth _(λ) is calculated by the following method.
Rth _(λ) is defined as Re _(λ) from −50 ° with respect to the film normal direction, with the in-plane slow axis (determined by KOBRA 21ADH or WR) as the tilt axis (rotary axis). Measured at 11 points by making light of wavelength λ nm incident in 10 ° steps up to + 50 °, and based on the measured retardation value, average refractive index assumption value and input film thickness value. KOBRA 21ADH or WR is calculated.
In the above measurement, as the assumed value of the average refractive index, values in the polymer handbook (John Wiley & Sons, Inc.) and catalogs of various optical films can be used. If the average refractive index is not known, it 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). The KOBRA 21ADH or WR calculates nx, ny, and nz by inputting the assumed value of the average refractive index and the film thickness. Nz = (nx−nz) / (nx−ny) is further calculated from the calculated nx, ny, and nz.

In the present specification, the maximum absorption wavelength (λ _max ) is a value measured in UV-3150 (manufactured by SHIMADZU Co., Ltd.).

(Configuration of liquid crystal display device)
FIG. 1 is a diagram showing a configuration of a liquid crystal display device of the present invention.
As shown in FIG. 1, the OCB mode liquid crystal display device includes a liquid crystal layer in which liquid crystal bends with respect to the substrate surface when a voltage is applied, that is, black display, a substrate 6 and a substrate 8 sandwiching the liquid crystal layer. A liquid crystal cell comprising:
As for the board | substrate 6 and the board | substrate 8, the alignment process is given to the surface at the side of a liquid crystal layer. The orientation direction (rubbing direction) is indicated by an arrow RD. In the case of the back surface, it is indicated by a broken line arrow. The polarizing films 1 and 101 are disposed so as to sandwich the liquid crystal cell, and the transmission axis 2 of the polarizing film 1 and the transmission axis 102 of the polarizing film 101 are orthogonal to each other and in the RD direction of the liquid crystal layer of the liquid crystal cell. And 45 ° with respect to each other.
An optical compensation film 13A (113A) is disposed between the polarizing film 1 (101) and the liquid crystal cell. The optical compensation film 13A (113A) is composed of a cellulose acylate film 13a (113a) and a discotic compound. The optically anisotropic layer 5 (9) is fixed in a hybrid alignment state in which the inclination angle with respect to the film plane is different in the thickness direction. In the cellulose acylate film 13a (113a), the slow axis 4a (104a) is arranged in parallel with the direction of the transmission axis 2 (102) of the polarizing film 1 (101) adjacent thereto.

The liquid crystal cell in FIG. 1 includes a liquid crystal layer formed of an upper substrate 6 and a lower substrate 8 and liquid crystal molecules 7 sandwiched between them. An alignment film (not shown) is formed on the surface of the substrate 6 and the substrate 8 that is in contact with the liquid crystal molecules 7 (hereinafter sometimes referred to as “inner surface”). The orientation of the molecules 7 is controlled in a parallel direction with a pretilt angle.
Further, on the inner surfaces of the substrate 6 and the substrate 8, a transparent electrode (not shown) capable of applying a voltage to the liquid crystal layer made of the liquid crystal molecules 7 is formed.
In the present invention, the product Δn · d of the thickness d (μm) of the liquid crystal layer and the refractive index anisotropy Δn is preferably 0.1 to 1.5 μm, more preferably 0.2 to 1.5 μm. Is more preferably 0.3 to 1.2 μm, and particularly preferably 0.4 to 1.0 μm. In these ranges, since the white display luminance when white voltage is applied is high, a bright and high-contrast display device can be obtained. The liquid crystal material to be used is not particularly limited, but in a mode in which an electric field is applied between the upper and lower substrates 6 and 8, the liquid crystal material having a positive dielectric anisotropy such that the liquid crystal molecules 7 respond in parallel to the electric field direction. Is used.

For example, when the liquid crystal cell is an OCB mode liquid crystal cell, the dielectric anisotropy between the upper substrate 6 and the lower substrate 8 is positive and Δn = 0.16 and Δε = 5 or so. A liquid crystal material or the like can be used.
The thickness d of the liquid crystal layer is not particularly limited, but can be set to about 4 μm when the liquid crystal having the characteristics in the above range is used. The brightness at the time of white display changes depending on the thickness Δ and the product Δn · d of the refractive index anisotropy Δn when white voltage is applied, so that sufficient brightness can be obtained when white voltage is applied. The Δn · d of the liquid crystal layer in the non-application state is preferably set to be in the range of 0.4 to 1.0 μm.

In addition, in the OCB mode liquid crystal display device, the addition of a chiral agent generally used in the TN mode liquid crystal display device is rarely used because it deteriorates the dynamic response characteristics, but in order to reduce alignment defects. May be added.
In addition, the multi-domain structure is advantageous for adjusting the alignment of the liquid crystal molecules in the boundary region between the domains.
Here, the multi-domain structure refers to a structure in which one pixel of a liquid crystal display device is divided into a plurality of regions. For example, in the OCB mode, a multi-domain structure is preferable because the viewing angle characteristics of luminance and color tone are improved.
Specifically, each pixel is composed of two or more (preferably 4 or 8) regions in which the initial alignment state of the liquid crystal molecules is different from each other, and averaging is performed. Can be reduced. Further, the same effect can be obtained even if each pixel is constituted by two or more different regions where the alignment direction of liquid crystal molecules continuously changes in a voltage application state.

The transparent support 13a (113a) may function as a support for the optically anisotropic layer 5 (9), may function as a protective film for the polarizing film 1 (101), You may have both functions. That is, the polarizing film 1 (101), the transparent support 13a (113a), and the optically anisotropic layer 5 (9) may be incorporated into the liquid crystal display device as an integrated laminate, Each may be incorporated as a single member.
Further, a protective film for a polarizing film may be separately disposed between the transparent support 13a (113a) and the polarizing film 1 (101), but the protective film is not disposed. Is preferred. The slow axis 14a of the transparent support 13a and the slow axis 114a of the transparent support 113a are preferably substantially parallel or orthogonal to each other. When the slow axis 14a of the transparent support 13a and the slow axis 114a of the transparent support 113a are orthogonal to each other, the birefringence of each transparent support cancels each other, thereby perpendicularly entering the liquid crystal display device. It is possible to reduce deterioration of optical characteristics of light. Further, in a mode in which the slow axes 14a and 114a are parallel to each other, when there is a residual phase difference in the liquid crystal layer, this phase difference can be compensated for by birefringence of the protective film.

  Regarding the transmission axis 2 (102) of the polarizing film 1 (101), the slow axis direction 14a (114a) of the transparent support 13a (113a), and the alignment direction of the liquid crystal molecules 7, the materials used for each member and the display mode Then, the optimum range is adjusted according to the laminated structure of the members. That is, the transmission axis 2 of the polarizing film 1 and the transmission axis 102 of the polarizing film 101 are arranged so as to be substantially orthogonal to each other. However, the liquid crystal display device of the present invention is not limited to this configuration.

The optically anisotropic layer 5 (9) is disposed between the transparent support 13a (113a) and the liquid crystal cell. The optically anisotropic layer 5 (9) is a layer formed from a composition containing a liquid crystal compound, for example, a rod-like compound or a discotic compound.
In the optically anisotropic layer 5 (9), the molecules of the liquid crystalline compound are fixed in a predetermined alignment state.
The orientation average direction 5a (9a) at least at the interface of the transparent support 13a (113a) of the molecular symmetry axis of the liquid crystalline compound in the optically anisotropic layer 5 (9) and the in-plane of the transparent support 13a (113a) Intersects with the slow axis 14a (114a) of approximately 45 °. When arranged in such a relationship, the optically anisotropic layer 5 (9) causes retardation with respect to the incident light from the normal direction, does not cause light leakage, and incident light from the oblique direction. In contrast, the effects of the present invention can be sufficiently achieved. Even at the interface on the liquid crystal cell side, the orientation average direction of the molecular symmetry axis of the optically anisotropic layer 5 (9) is about 45 with respect to the slow axis 14a (114a) in the plane of the transparent support 13a (113a). It is preferable to make an angle.

  In addition, the orientation average direction 5a on the polarizing film side (optical anisotropic layer interface side) of the molecular symmetry axis of the liquid crystalline compound of the optically anisotropic layer 5 is substantially the same as the transmission axis 2 of the polarizing film 1 located closer. It is preferable to arrange at 45 °. Similarly, the alignment average direction 9a on the polarizing film side (optical anisotropic layer interface side) of the molecular symmetry axis of the liquid crystalline compound of the optically anisotropic layer 9 is closer to the transmission axis 102 of the polarizing film 101 positioned closer to the optical axis. It is preferable to arrange at approximately 45 °. When arranged in such a relationship, optical switching can be performed according to the sum of the retardation generated in the optically anisotropic layer 5 (9) and the retardation generated in the liquid crystal layer, and incident light from an oblique direction. In contrast, the effects of the present invention can be sufficiently achieved.

<Principle of image display>
Next, the principle of image display of the liquid crystal display device will be described with reference to FIG.
In a driving state in which a driving voltage corresponding to black is applied to the transparent electrodes (not shown) of the substrate 6 and the substrate 8 of the liquid crystal cell, the liquid crystal molecules 7 in the liquid crystal layer are bend-aligned, and the surface at that time The internal retardation is canceled by the in-plane retardation of the optically anisotropic layer 5 (9). As a result, the polarization state of incident light hardly changes. Since the transmission axis 2 of the polarizing film 1 and the transmission axis 102 of the polarizing film 101 are orthogonal to each other, the light incident from below is polarized by the polarizing film 101 and passes through the liquid crystal cell while maintaining the polarization state. And is blocked by the polarizing film 1.
That is, the liquid crystal display device of FIG. 1 realizes an ideal black display in the driving state. On the other hand, in a driving state in which a driving voltage corresponding to white is applied to a transparent electrode (not shown), the liquid crystal molecules 7 in the liquid crystal layer have a bend alignment different from the bend alignment corresponding to black. It changes when the retardation is black. As a result, the in-plane retardation of the optically anisotropic layer 5 (9) does not cancel, and the polarization state changes by passing through the liquid crystal cell, and passes through the polarizing film 1. That is, a white display is obtained.

Conventionally, in the OCB mode, there is a problem that even if the front contrast is high, the contrast decreases in an oblique direction. At the time of black display, high contrast is obtained by compensation of the liquid crystal cell and the optically anisotropic layer in the front, whereas birefringence and rotation of the polarization axis occur in the liquid crystal molecules 7 when observed obliquely.
Further, the crossing angle between the transmission axis 2 of the polarizing film 1 and the transmission axis 102 of the polarizing film 101 is 90 ° orthogonal at the front, but is shifted from 90 ° when viewed obliquely. Conventionally, due to these two factors, there has been a problem that leakage light occurs in an oblique direction and the contrast is lowered.
In the liquid crystal display device of the present invention having the configuration shown in FIG. 1, the transparent support 13 a (113 a) having optical characteristics satisfying specific conditions, in which Re / Rth in R, G, and B do not match each other, is used. Therefore, light leakage in an oblique direction during black display is reduced, and contrast is improved.

More specifically, the present invention is different for each wavelength of light of R, G, and B wavelengths incident in an oblique direction by using the transparent support having the optical characteristics and the optically anisotropic layer. Optical compensation is possible with the slow axis and retardation.
Furthermore, the optically anisotropic layer 5 (9) in which the orientation of the liquid crystalline compound is fixed has an orientation average direction at the transparent support side interface of the symmetry axis of the molecules of the liquid crystalline compound and a slow axis of the transparent support of 45. By arranging them so as to cross each other, it is possible to perform a unique compensation method for OCB orientation at all wavelengths.
As a result, the viewing angle contrast of black display is greatly improved, and the coloring in the viewing angle direction of black display is further reduced.
In particular, when the viewing angle is swung in the left-right direction, for example, there is a difference in coloring at the polar angle 60 ° in the azimuth angle 0 ° direction and the 180 ° direction, and left-right asymmetry has occurred. Is done.
Here, in this specification, as the wavelengths of R, G, and B, R has a wavelength of 630 nm, G has a wavelength of 550 nm, and B has a wavelength of 450 nm. The wavelengths of R, G, and B are not necessarily represented by these wavelengths, but are considered to be wavelengths that are suitable for defining optical characteristics that exhibit the effects of the present invention.

  In particular, in the present invention, attention is paid to Re / Rth which is a ratio of Re and Rth of the transparent support. This is because the value of Re / Rth determines the axes of two intrinsic polarizations in the propagation of light traveling obliquely through a biaxial birefringent medium. The two axes of intrinsic polarization in the propagation of light traveling obliquely through a biaxial birefringent medium are the major axis and the minor axis of the cross section formed when the refractive index ellipsoid is cut in the normal direction of the light traveling direction. Corresponds to the direction. In FIG. 2, when light traveling in an oblique direction is incident on the transparent support used in the present invention, the direction of one axis of two intrinsic polarizations, that is, the angle of the slow axis in this case, and Re / Rth An example of the result of calculating the relationship is shown.

In FIG. 2, the propagation direction of light is assumed to be an azimuth angle = 45 ° and a polar angle = 34 °. As shown in FIG. 2, the angle of the slow axis does not depend on the wavelength of incident light, but is uniquely determined by Re / Rth. How the polarization state of incident light changes by passing through the transparent support is mainly determined by the slow axis orientation of the transparent support and the retardation of the transparent support. Then, the Re / Rth values are almost the same regardless of the R, G, and B wavelengths, that is, the slow axis angles are almost the same.
On the other hand, in the present invention, by specifying the Re / Rth relationship separately for each of the R, G, and B wavelengths, both the slow axis and the retardation, which are factors that mainly determine the change in the polarization state, can be obtained. Optimization is performed for each wavelength of R, G, and B.
Then, when light in an oblique direction passing through the transparent support passes through the optically anisotropic layer in which the orientation of the liquid crystal compound is fixed and further passes through the liquid crystal layer of bend orientation, the retardation and the upper and lower polarizing films at any wavelength The value of Re / Rth of the transparent support is adjusted according to the wavelength so that the two factors that the apparent transmission axis is deviated from the front can be compensated simultaneously.
Specifically, by increasing the Re / Rth of the transparent support as the wavelength increases, the difference in polarization state in R, G, and B caused by the wavelength dispersion of the optically anisotropic layer and the liquid crystal cell layer is eliminated. It became possible.
As a result, complete compensation is possible and reduction in contrast is reduced. If the parameters of the film are determined with R, G, and B representing the entire visible light region, almost complete compensation can be achieved in the entire visible light region.

Here, polar angle and azimuth angle are defined. The polar angle is the normal direction of the optical compensation film surface, that is, the tilt angle from the z-axis in FIG. 1. For example, the normal direction of the optical compensation film surface is the direction of polar angle = 0 °.
The azimuth angle represents an azimuth rotated counterclockwise with respect to the positive direction of the x axis. For example, the positive direction of the x axis is the direction of the azimuth angle = 0 °, and the positive direction of the y axis is The direction of azimuth = 90 °.
The oblique direction in which black display is most problematic is the case where the polar angle is not 0 ° and the azimuth angle = 0 °, 90 °, 180 because the polarization axis of the polarizing layer is ± 45. ° Mainly refers to the case of 270 °.

  In order to explain the effect of the present invention in more detail, the polarization state of the light incident on the liquid crystal display device is shown on the Poincare sphere in FIG. In FIG. 3, the S2 axis is an axis that penetrates vertically from the top to the bottom of the drawing, and FIG. 3 is a view of the Poincare sphere viewed from the positive direction of the S2 axis. Further, since FIG. 3 is shown in a plan view, the displacement of the point before and after the change of the polarization state is indicated by a straight arrow in the figure. The change in the polarization state due to the passage is expressed by rotating a specific angle on a Poincare sphere around a specific axis determined according to each optical characteristic. The same applies to FIGS. 5 and 6 below.

3A is a diagram showing a change in the polarization state of the G light incident from the left 60 ° to the liquid crystal display device of FIG. 1, and FIG. 3B shows a change in the polarization state of the G light incident from the right 60 °. FIG. The optical characteristics of the transparent support 13a (113a) and the optical characteristics of the optically anisotropic layer 5 (9) were calculated on the assumption that the conditions were the same as those of the Poincare sphere in FIG. The G light incident from the left 60 ° changes its polarization state as indicated by a point on the Poincare sphere in FIG. 3A.
Specifically, the polarization state I1 of the G light that has passed through the polarizing film 101 passes through the transparent support 113a, passes through I2, passes through the optically anisotropic layer 9, passes through I3, and the liquid crystal layer of the liquid crystal cell during black display Passes through the optical anisotropic layer 5, passes through the optically anisotropic layer 5, passes through the transparent support 13a, and passes through the transparent support 13a to be in the polarization state of I6 and is blocked by the polarizing film 1 to display ideal black. On the other hand, the G light incident from the right 60 ° also changes its polarization state from I1 ′ → I2 ′ → I3 ′ → I4 ′ → I5 ′ → I6 ′.
Examining the change of the polarization state, the change of the polarization state by passing through the optically anisotropic layer 5 (9) and the liquid crystal layer 7 is mirror-symmetric with the incident light from the left 60 ° and the right 60 °. On the other hand, the change in the polarization state due to passing through the transparent support 13a (113a) coincides with the incident light from the left 60 ° and the right 60 °. In order to reduce the left and right black spots and the left and right color shifts, it is necessary to satisfy this compensation condition at the left and right at the same time. That is, not only the G light but also the R (red) and B (blue) incident light in the visible light range, the positions of I6 and I6 ′ coincide with each other, and the polarized light whose position is blocked by the polarizing film 1 It must be in a position that indicates the state. The transition is represented by a straight line in the figure, but is not necessarily limited to a linear transition on the Poincare sphere.

FIG. 4 is a diagram showing a configuration of a conventional OCB mode liquid crystal display device disclosed in Japanese Patent Laid-Open No. 11-316378. As shown in FIG. 4, in this configuration, the optical compensation film whose Re / Rth exhibits the above wavelength dependency is not disposed, and instead, the transparent support 3a (103a) is disposed. The transparent support 3a (103a) is used for the purpose of supporting the optically anisotropic layer 5 (9) and is made of a general polymer film.
Accordingly, there is no wavelength dependency on Re / Rth as shown by the transparent support 13a (113a), and the same Re and Rth are exhibited at any of the R, G, and B wavelengths.
As a result, in the conventional OCB mode liquid crystal display device, when voltage is applied, that is, when black is displayed, the front retardation of the liquid crystal cell and the optically anisotropic layer is offset in the front and black can be obtained. In the direction, there is a problem that light leakage of black display cannot be completely suppressed. In addition, sufficient viewing angle contrast cannot be obtained, and compensation cannot be made at all wavelengths.

In order to explain in more detail, the result of calculating the polarization state of the R, G, B light incident on the OCB mode liquid crystal display device of the conventional configuration shown in FIG. 4 is shown on the Poincare sphere in FIG. FIG. 5A is a diagram showing changes in the polarization state of light incident from the left 60 ° with respect to R, G, and B. FIG. 5B shows changes in the polarization state of light incident from the right 60 ° in R, G, and B. It is the figure shown about each. In the drawing, the polarization state of R incident light is indicated by IR, the polarization state of G incident light is indicated by IG, and the polarization state of B incident light is indicated by IB. Further, as a configuration of the conventional OCB mode liquid crystal display device, the transparent support 3a (103a) in FIG. 4 has Re = 45 nm and Rth = 160 nm at any wavelength of R, G, and B. The calculation was performed assuming that the optically anisotropic layer 5 (9) had Re = 30 nm.
First, in FIG. 5A, the polarization state after passing through the polarizing film 101, IR1, IG1, and IB1 are equal. Paying attention to the change in the polarization state of the B light, the B light incident from the left 60 ° is the same as the direction in which the polarization state IB2 after passing through the transparent support 103a transits by passing through the optically anisotropic layer 9. The B light incident in the right direction and incident from 60 ° to the right is shifted in the direction opposite to the direction in which the polarization state IB2 ′ after passing through the transparent support 103a transits by passing through the optically anisotropic layer 9. Can understand. In other words, the light incident from the left and the light incident from the right differ in how the transparent support 103a affects the polarization state. As a result, the final transition state IR6 of the R, G and B incident light from the left 60 °, the position of IG6 and IB6, the final transition state IR6 ′ of the R, G and B incident light from the right 60 °, The positions of IG6 ′ and IB6 ′ are not only coincident, but are completely different at the left 60 ° and the right 60 °. Therefore, left and right black light leakage and left and right color misregistration occur, and it has been difficult to improve these simultaneously.

In the present invention, by disposing a transparent support exhibiting specific optical characteristics, the left and right black light leakage and the left and right color shift of the OCB mode liquid crystal display device are simultaneously improved. In order to explain in more detail, the result of calculating the polarization state of the R, G, B light passing through the OCB mode liquid crystal display device having the configuration of the present invention shown in FIG. 1 is shown on the Poincare sphere in FIG. It was.
6A is a diagram showing changes in the polarization state of light incident from the left 60 ° for each of R, G, and B. FIG. 6B shows the change in the polarization state of light incident from the right 60 ° as R, G. It is the figure shown about each of B and B.
6A and 6B, the polarization state of R incident light is indicated by IR, the polarization state of G incident light is indicated by IG, and the polarization state of B incident light is indicated by IB. The transparent support 13 (113) has a Re / Rth (Re ₍₄₅₀₎ / Rth ₍₄₅₀₎ ) of 0.17 at a wavelength of ₄₅₀ nm and a Re / Rth (Re ₍₅₅₀₎ / Rth ₍₅₅₀₎ ) of ₅₅₀ nm. Is 0.28, Re / Rth ((Re ₍₆₃₀₎ / Rth ₍₆₃₀₎ )) at a wavelength of 650 nm is 0.39, and Rth (Rth ₍₅₅₀₎ ) at a wavelength of 550 nm is 160 nm. Calculated. Re of the optically anisotropic layer 5 (9) was assumed to be the same value as the Poincare sphere shown in FIG.

  As shown in FIG. 6A and FIG. 6B, the R light, G light, and B light incident from the left and right pass through the transparent support 113a, and are all in the vicinity of S1 = 0, and the transparent support 113a Reflecting the wavelength dependency of Re / Rth, the polarization state changes to a shifted position. This shift makes it possible to cancel the polarization state shift that the R light, the G light, and the B light receive due to the wavelength dispersion of the optically anisotropic layer 9 (5) and the liquid crystal layer 7. As a result, the light that has entered from either the left or right direction can have the same final transition point regardless of the wavelength. As a result, it is possible to simultaneously improve the left and right black light omission and the left and right color shift.

  The present invention relates to the transparent support (cellulose acylate film) having optical characteristics in which the wavelength dispersion of the retardation is different between the normal direction and the oblique direction inclined with respect to the normal direction, for example, the polar angle direction of 60 °, In addition, the optical characteristics of the transparent support and the optically anisotropic layer are positively used for optical compensation by using the optically anisotropic layer. ing. As long as this principle is used, the scope of the present invention is not limited by the display mode of the liquid crystal layer, and a liquid crystal display having a liquid crystal layer of any display mode such as VA mode, IPS mode, ECB mode, and TN mode. It can also be used for devices.

  Further, the liquid crystal display device of the present invention is not limited to the configuration shown in FIG. 1 and may include other members. For example, a color filter may be disposed between the liquid crystal cell and the polarizing film. In the case of use as a transmission 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.

  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 TFT or MIM. Of course, an embodiment applied to a passive matrix liquid crystal display device represented by STN type called time-division driving is also effective.

(Optical compensation film)
The optical compensation film of the present invention has at least a transparent support. Moreover, you may form an optically anisotropic layer on the said transparent support body as needed. Hereafter, each element which comprises the optical compensation film of this invention is demonstrated in detail.

<Transparent support>
The transparent support constituting the optical compensation film of the present invention is not particularly limited as long as it is a transparent film and is appropriately selected according to the purpose. A combination of a polymer layer and a polymer film may be used. As a material for the polymer film, a synthetic polymer is generally used. Examples of the synthetic polymer include polycarbonate, polysulfone, polyethersulfone, polyacrylate, polymethacrylate, norbornene resin, and cellulose ester.

  As a method for controlling Re of the transparent support, a method in which the transparent support is stretched at a temperature of (Tg + 15) to (Tg + 100) ° C. when the glass transition point of the transparent support is (Tg) is preferably used. It is done. The stretching step for stretching the transparent support may include a shrinking step for shrinking.

In the present invention, the reverse wavelength dispersion characteristic of Re and the forward wavelength dispersion characteristic of Rth, which were difficult to achieve with a single film, are achieved by sharing and adjusting as follows. That is, the reverse wavelength dispersion characteristic of Re is mainly performed by changing the stretching condition of the film, and the forward wavelength dispersion characteristic of Rth is mainly performed by adding an additive (Rth increasing agent).
Here, it has been found that the stretched result is expressed by the orientation degree P (alignment order parameter; Baifukan, Liquid Crystal Dictionary P.175, published on 12/5, 1989) described in the present invention.
FIG. 7A shows the chromatic dispersion in the case where only the additive is added without stretching, and FIG. 7B shows the chromatic dispersion in the case where the additive is not added after stretching.
As shown in FIGS. 7A and 7B, in both cases, the reverse dispersion characteristic of Re and the forward dispersion characteristic of Rth cannot be achieved simultaneously.
On the other hand, FIG. 7C shows the wavelength dispersion in the case where stretching is performed and an additive is further added.
As shown in FIG. 7C, in order to achieve the reverse wavelength dispersion characteristic of Re and the forward wavelength dispersion characteristic of Rth with one film, these two conditions (stretching and addition of an Rth increasing agent) are required at the same time. It is clear that

<< degree of orientation P >>
The transparent support constituting the optical compensation film of the present invention is preferably produced so that Re at each wavelength becomes a desired value by stretching in a high temperature region. The mechanism will be described by taking cellulose acylate as the most preferable embodiment as an example.
Cellulose acylate is formed of a main chain composed of a glucopyranose ring and a side chain composed of an acyl group. When a film made of cellulose acylate is stretched, Re is expressed by the polymer main chain being oriented in the stretching direction.
As a result of extensive research, the present inventor has found that Re at 450 nm decreases and Re increases at 650 nm by stretching at a very high temperature of 175 ° C. or higher (Tg of the cellulose acylate used is 148 ° C.). I found it.
This is due to the fact that the orientation of cellulose acylate is remarkably increased by stretching in the high temperature region as described above. The degree of orientation P calculated by X-ray diffraction measurement was used as a parameter indicating the orientation of cellulose acylate. For X-ray diffraction measurement, RAPID R-AXIS manufactured by Rigaku Denki Kogyo Co., Ltd. was used, CuKα rays were used as the X-ray source, and X-rays were generated at 40 kV-36 mA. The collimator was 0.8 mmφ, and the cellulose acylate film as a sample was fixed using a transmission sample stage. The measurement was performed under the conditions of 22 ° C. and 60% RH. The orientation degree P of the cellulose acylate defined by the following formula (A) from the detected X-ray pattern is preferably 0.05 to 0.30, more preferably 0.06 to 0.30. 0.08 to 0.30 is particularly preferable. The upper limit value of the degree of orientation P is 1.0.

P = <3cos ² β-1> / 2... Formula (A)

However, <cos ² β> = ∫ (0, π) cos ² βI (β) sinβdβ / ∫ (0, π) I (β) sinβdβ.
In the above formula, β is an angle formed by an incident surface of incident X-rays and a certain direction in the surface of the transparent support (cellulose acylate film), and I is an X-ray diffraction chart measured at an angle β. Is the diffraction intensity at 2θ = 8 °. In addition, in the cellulose acylate film after high-temperature stretching, a peak of X-ray diffraction that is considered to be derived from crystallization appears, and crystallization of the cellulose acylate film is effective for the desired Re expression.

  In order to improve the color shift of the liquid crystal display device, it is also important to control Rth. In the present invention, in order to selectively control Rth, it is preferable to use an Rth raising agent. The Rth raising agent is preferably a compound that selectively expresses Rth relative to Re in the transparent support. Specifically, when the transparent support is uniaxially stretched at a fixed end of 115% at 160 ° C., the difference in Rth value before and after the addition / re difference before and after the addition is preferably 5 or more, more than 8 Is more preferable, and 10 or more is still more preferable.

In the optical compensation film of the present invention, Rth can be controlled by the added Rth increasing agent and the stretching step during the production of the transparent support.
In order to achieve a desired Rth value, it is necessary to control the aggregation state of the additive in the transparent support.
Effective as a means for controlling the aggregation state of the additive in the transparent support is control of the drying rate in the drying step after casting the polymer solution, which is the raw material of the transparent support, on the band.
In the drying step, the average drying rate in the region where the volatile fraction during the drying step of the transparent support is 10 to 100% by mass is preferably at least 1.2% by mass / min, and 1.4% by mass More preferably, it is set to not less than / min. The Rth-increasing agent in the transparent support dried under these conditions has a small aggregate size and can achieve the desired Rth while maintaining the transparency of the transparent support.

The Re ₍₅₅₀₎ range for the transparent support constituting the optical compensation film of the present invention is preferably 10 to 100 nm, more preferably 10 to 90 nm, and still more preferably 20 to 80 nm.
Further, the range of Rth ₍₅₅₀₎ relating to the transparent support constituting the optical compensation film of the present invention is preferably 100 to 200 nm, more preferably 110 to 200 nm, and further preferably 120 to 200 nm. preferable.

The range of the following formula (3) relating to the transparent support constituting the optical compensation film of the present invention is preferably 0.40 to 0.95, more preferably 0.55 to 0.8, and 0 More preferably, it is 55-0.75.
Moreover, the range of the following formula (4) relating to the transparent support constituting the optical compensation film of the present invention is preferably 1.02 to 1.50, more preferably 1.10 to 1.45. More preferably, 1.10 to 1.42.

0.5 <Re ₍₄₅₀₎ / Re ₍₅₅₀₎ <1.0 Formula (3)
1.0 <Re ₍₆₃₀₎ / Re ₍₅₅₀₎ <1.5 (4)

  Here, the absolute value of Re is preferably controlled within a preferable range depending on the mode of each liquid crystal layer. For example, in the case of OCB and VA modes, 20 to 110 nm is preferable, 20 to 100 nm is more preferable, and 35 to 90 nm is still more preferable.

The range of the following formula (5) relating to the transparent support constituting the optical compensation film of the present invention is preferably 1.01-1.50, more preferably 1.02-1.40. More preferably, it is 1.05-1.30.
The range of the following formula (6) relating to the transparent support constituting the optical compensation film of the present invention is preferably 0.60 to 1.00, more preferably 0.65 to 0.99. 0.75 to 0.97 is more preferable.

1.0 <Rth ₍₄₅₀₎ / Rth ₍₅₅₀₎ <1.5 (5)
0.5 <Rth ₍₆₃₀₎ / Rth ₍₅₅₀₎ <1.0 (6)

Further, the retardation in the thickness direction (Rth) of the entire transparent support has a function for canceling the retardation of the liquid crystal layer in the thickness direction at the time of black display. Therefore, it is preferable depending on the mode of each liquid crystal layer. The range is also different.
For example, an OCB mode liquid crystal cell (for example, an OCB mode liquid crystal cell having a liquid crystal layer having a product Δn · d of thickness d (μm) and refractive index anisotropy Δn of 0.2 to 1.5 μm). When used for optical compensation, it is preferably 70 to 400 nm, more preferably 100 to 400 nm, and even more preferably 130 to 200 nm.

<< cellulose acylate >>
As the raw material cotton of the transparent support (hereinafter sometimes referred to as cellulose acylate (film)) selected as the material of the support of the present invention, a known raw material can be used (for example, the Japan Institute of Invention and Innovation Technical Report). 2001-1745).
Cellulose acylate can also be synthesized by a known method (for example, see Mita et al., Wood Chemistry pages 180-190 (Kyoritsu Shuppan, 1968)).
The average degree of polymerization of cellulose acylate is preferably 200 to 700, more preferably 250 to 500, and still more preferably 250 to 350.
The cellulose ester used in the present invention preferably has a narrow molecular weight distribution of Mw / Mn (Mw is a mass average molecular weight, Mn is a number average molecular weight) by gel permeation chromatography.
The specific value of Mw / Mn is preferably 1.5 to 5.0, more preferably 2.0 to 4.5, and further preferably 3.0 to 4.0. preferable.

The acyl group of the cellulose acylate film of the present invention is not particularly limited, but an acetyl group or a propionyl group is preferably used, and an acetyl group is particularly preferable. The degree of substitution of all acyl groups is preferably 2.7 to 3.0, more preferably 2.8 to 2.95. In the present embodiment, the substitution degree of the acyl group is a value calculated according to ASTM (AMERICA SOCIETY FOR TESTING AND MATERIALS) D817.
The acyl group is particularly preferably an acetyl group, and when cellulose acetate having an acyl group as the acetyl group is used, the acetylation degree is preferably 57.0 to 62.5%, and 58.0 to 62.0. % Is more preferable. When the acetylation degree is within this range, Re does not become larger than a desired value due to the conveying tension during casting, there is little in-plane variation, and there is little change in retardation value due to temperature and humidity.
In particular, it is obtained by substituting the hydroxyl group of the glucose unit constituting the cellulose of the cellulose acylate film with an acyl group having 2 or more carbon atoms, and the substitution degree of the hydroxyl group at the 2-position of the glucose unit with the acyl group is DS2, 3 When the substitution degree of the hydroxyl group at the position is DS3 and the substitution degree of the acyl group at the 6-position hydroxyl group is DS6, if the following formula (I) and the following formula (II) are satisfied, the Re by temperature and humidity The fluctuation of the value is small, which is preferable.

2.0 ≦ DS2 + DS3 + DS6 ≦ 3.0... Formula (I)
DS6 / (DS2 + DS3 + DS6) ≧ 0.315 Formula (II)

<< Drawing method >>
The cellulose acylate film of the present invention exhibits a function by stretching as described above.
Below, the preferable extending | stretching method for this invention is demonstrated concretely.
The cellulose acylate film of the present invention is preferably stretched in the width direction when applied to a polarizing plate. About this stretching method, for example, in JP-A-62-115035, JP-A-4-152125, JP-A-4-284221, JP-A-4-298310, JP-A-11-48271, etc. Are listed.
In addition, the cellulose acylate film of the present invention is stretched under the condition of 155 to 250 ° C., which is +5 to + 100 ° C. of Tg (150 ° C.) of the film as described above.
The cellulose acylate film of the present invention may be stretched uniaxially or biaxially.
Moreover, the cellulose acylate film of the present invention can be stretched by a treatment during drying, and is particularly effective when a solvent remains. For example, when the speed of the cellulose acylate film is adjusted so that the take-up speed of the cellulose acylate film is higher than the peel-off speed of the cellulose acylate film, the cellulose acylate film is stretched.
The cellulose acylate film can also be stretched by conveying the cellulose acylate film while holding it with a tenter and gradually widening the width of the tenter.
Furthermore, after the cellulose acylate film is dried, it can be stretched using a stretching machine (preferably uniaxial stretching using a long stretching machine).
The stretching ratio of the cellulose acylate film of the present invention (ratio of increase due to stretching relative to the original length) is preferably 0.5 to 300%, more preferably 1 to 200%, and more preferably 1 to 100%. % Stretching is more preferred.

The cellulose acylate film of the present invention is preferably produced by sequentially or continuously performing a film-forming step by a solvent cast method and a drawing step for drawing the formed film, and the draw ratio is 1.2. It is preferable that it is not less than twice and not more than 1.8 times.
Moreover, the said extending process may be performed by 1 step | paragraph and may be performed by multiple steps | paragraphs. When it is performed in multiple stages, the product of the stretching ratios may be in the above range (1.2 to 1.8 times).

The stretching speed is preferably 5 to 1,000% / min, and more preferably 10 to 500% / min.
Furthermore, it is preferable that the said extending process is performed with a heat roll and / or a radiant heat source (IR heater etc.) and warm air. Moreover, you may provide a thermostat in order to improve the uniformity of temperature. When performing uniaxial stretching by roll stretching, it is preferable that L / W which is a ratio of the distance (L) between rolls and the film width (W) of a protective film is 2.0-5.0.

Furthermore, it is preferable to provide a preheating step before the stretching step, and heat treatment may be performed after the stretching step. The heat treatment temperature is preferably a temperature between 20 ° C. lower than the glass transition temperature (Tg) of the cellulose acetate film and 10 ° C. higher than the glass transition temperature (Tg). It is preferably 3 minutes.
The heating method may be zone heating, partial heating using an infrared heater, or slitting both ends of the cellulose acetate film during or at the end of the heating process. And it is preferable to collect | recover the slit waste produced at this time, and to reuse as a raw material.

  Regarding the tenter, in Japanese Patent Application Laid-Open No. 11-077718, when the web is dried while maintaining the width with the tenter, the blowing method, the blowing angle, the wind speed distribution, the wind speed, the air volume, the temperature difference, the air volume difference, and the upper and lower air blowing are performed. By appropriately controlling the use of air volume ratio and high specific heat drying gas, etc., it is possible to ensure quality prevention such as flatness when increasing the speed by the solution casting method or widening the web width. These techniques may be employed in the present invention.

  Japanese Patent Application Laid-Open No. 11-077782 describes a technique in which a stretched thermoplastic resin film is heat treated by providing a temperature gradient in the width direction of the film in the thermal relaxation process after the stretching process in order to prevent unevenness. This technique may be employed in the heat treatment step.

  Japanese Patent Laid-Open No. 4-204503 describes a technique for stretching the film so that the solvent content of the film is 2 to 10% based on the solid content in order to prevent the occurrence of unevenness, and this technique is employed in the present invention. May be.

  Japanese Patent Application Laid-Open No. 2002-248680 discloses that tenter clip biting width D ≦ (33 / (log stretch ratio × log volatile content)) in order to suppress curling due to the regulation of clip biting width. Describes a technique for suppressing curling and facilitating film conveyance after the stretching process, and this technique may be employed in the present invention.

  Japanese Patent Application Laid-Open No. 2002-337224 describes a technique for switching the tenter conveyance to the first half pin and the second half clip in order to achieve both high-speed soft film conveyance and stretching, and this technique is employed in the present invention. May be.

Japanese Patent Application Laid-Open No. 2002-187960 discloses that a cellulose ester dope solution is cast on a casting support for the purpose of easily improving the viewing angle characteristics and improving the viewing angle. The web (film) peeled off from the support for stretching is 1.0 to 4.0 times in at least one direction while the amount of residual solvent in the web is in the range of 100% by mass or less, particularly 10 to 100% by mass. An invention having optically biaxiality obtained by stretching is described.
As a further preferred embodiment of this technique, it is also described that the film is stretched 1.0 to 4.0 times in at least one direction while the amount of residual solvent in the web is 100% by mass or less, particularly 10 to 100% by mass. Has been.
In addition, as another stretching method of this technique, a difference in circumferential speed is applied to a plurality of rolls, and the roll is stretched in the longitudinal direction using the difference in circumferential speed between the rolls, and both ends of the web are fixed with clips or pins. A method of extending the gap between the pins in the direction of travel and extending in the vertical direction, a method of extending the width in the horizontal direction and extending in the horizontal direction, a method of extending the length and width simultaneously and extending in both the vertical and horizontal directions, a method of combining these, etc. Are also listed.
Furthermore, in the case of the so-called tenter method, it has been shown that driving the clip portion by the linear drive method is preferable because smooth stretching can be performed and the risk of breakage and the like can be reduced. You may employ | adopt for invention.

JP-A-2003-014933 discloses that an additive and a resin are added in order to produce an optical compensation film having little additive bleed-out, no delamination phenomenon between layers, and good slipperiness and excellent transparency. A dope A containing an additive and an organic solvent, and a dope B containing no additive or a resin having a lower additive content than the dope A, an additive and an organic solvent, and the dope A being a core layer Then, after co-casting on the support so that the dope B becomes a surface layer and evaporating the organic solvent until it can be peeled, the web is peeled off from the transparent support, and further in the resin film during stretching A technique is described in which the residual solvent is stretched 1.1 to 1.3 times in at least a uniaxial direction in the range of 3 to 50% by mass.
As a further preferred embodiment of this technique, the web is peeled from the support, and further stretched at least uniaxially in the uniaxial direction at a stretching temperature of 140 to 200 ° C., and a resin and an organic solvent are included. Dope A, dope B containing resin, fine particles, and organic solvent is prepared, until the dope A becomes a core layer and the dope B becomes a surface layer, and is co-cast on a transparent support until it becomes peelable. After evaporating the organic solvent, the web is peeled from the support, and further stretched 1.1 to 3.0 times in the uniaxial direction in the range of 3 to 50% by mass of the residual solvent in the resin film during stretching. Furthermore, the film is stretched 1.1 to 3.0 times at least in a uniaxial direction at a stretching temperature of 140 to 200 ° C., a dope A containing a resin, an organic solvent and an additive, and an additive or no additive. Resin with less content than Dope A A dope B containing an additive and an organic solvent, and a dope C containing a resin, fine particles, and an organic solvent are prepared. The dope A is a core layer, the dope B is a surface layer, and the dope C is a surface opposite to the dope B. After co-casting on the support so as to form a layer and evaporating the organic solvent until it can be peeled, the web is peeled from the support, and the amount of residual solvent in the resin film during stretching is 3 to 3 Stretching at least uniaxially 1.1 to 3.0 times in the range of 50% by mass, stretching at least uniaxially 1.1 to 3.0 times in the range of the stretching temperature of 140 to 200 ° C., Dope A The additive amount in the resin is 1 to 30% by mass with respect to the resin, the additive amount in the dope B is 0 to 5% by mass with respect to the resin, and the additive is a plasticizer, an ultraviolet absorber, or a retardation. Being a control agent, present in dope A and dope B The solvent is described to be preferable to use that it contains more than 50 wt% methylene chloride or methyl acetate with respect to the total organic solvents may be employed these techniques to the present invention.

Japanese Patent Application Laid-Open No. 2003-014933 discloses a transverse stretching machine called a tenter that stretches in the lateral direction by fixing both ends of the web with clips and pins and expanding the distance between the clips and pins in the lateral direction. It is described that can be preferably used.
Further, in this publication, in order to stretch or shrink in the longitudinal direction, the simultaneous biaxial stretching machine is used to expand or contract the interval in the transport direction of clips and pins in the transport direction (vertical direction). It is also disclosed that
Further, in this publication, when the clip portion is driven by the linear drive system, it is possible to smoothly stretch and reduce the risk of breakage, etc., and a method of stretching in the longitudinal direction is preferable. It has been shown that a method can be used in which a difference in circumferential speed is applied to the belt and the roll is stretched in the longitudinal direction by utilizing the difference in circumferential speed of the roll.
In addition, in this publication, these stretching methods can be used in combination, and the stretching process is performed in two or more stages, such as (longitudinal stretching, lateral stretching, longitudinal stretching) or (longitudinal stretching, longitudinal stretching). However, these techniques may be applied to the present invention.

  Japanese Patent Laid-Open No. 2003-004374 discloses that in order to prevent foaming of the tenter-dried web, improve detachability, and prevent dust generation, hot air from the dryer is applied to both edges of the web. In order not to hit, a technique is described in which the width of the dryer is formed shorter than the width of the web, and this technique may be employed in the present invention.

  Japanese Patent Application Laid-Open No. 2003-019757 discloses that the tenter drying web is prevented from being foamed, the releasability is improved, and dust is prevented from being generated. The technique which provides a wind-shielding board inside a part is described, You may employ | adopt this technique for this invention.

  Japanese Patent Application Laid-Open No. 2003-053749 discloses that the thickness after drying of both ends of a film carried by a pin tenter is X (μm) in order to stably carry and dry the film. When the average thickness after drying is T (μm), T ≦ 60 satisfies 40 ≦ X ≦ 200, and 60 <T ≦ 120, 40+ (T−60) × 0.2 ≦ X ≦ 300 Is satisfied, and in 120 <T, a technique that satisfies 52+ (T−120) × 0.2 ≦ X ≦ 400 is described, and this technique may be employed in the present invention.

  Japanese Patent Laid-Open No. 2-182654 discloses a tenter device in which a heating chamber and a cooling chamber are provided in a dryer of a multistage tenter so that wrinkles are not generated in the multistage tenter. A separate cooling technique is described and may be employed in the present invention.

  Japanese Patent Application Laid-Open No. 9-073315 describes a technique for increasing the inner pin density and decreasing the outer pin density in the pin tenter pins in order to prevent web breakage, wrinkles, and conveyance failure. This technique may be employed in the present invention.

  Japanese Patent Laid-Open No. 9-085846 discloses a web-type side edge holding pin in a tenter drying device in order to prevent foaming of the web itself and adhesion of the web to the holding means in the tenter. A technology is described in which the pin is cooled to below the foaming temperature of the web with a cooler, and the pin immediately before the web is entrapped is cooled to the gelation temperature of the dope + 15 ° C. or less in the duct type cooler. You may employ | adopt for this invention.

  Japanese Patent Laid-Open No. 2003-103542 discloses a surface of a web that cools the insertion structure and contacts the insertion structure in the pin tenter in order to prevent pin tenter loss and improve foreign matter. A technique relating to a solution casting method for preventing the temperature from exceeding the gelling temperature of the web is described, and this technique may be employed in the present invention.

Japanese Patent Application Laid-Open No. 11-077718 discloses a web in a tenter in order to prevent deterioration in quality such as flatness when the speed is increased by a solution casting method or the width of the web is widened by a tenter. Is dried, the wind speed is 0.5-20 (40) m / s, the transverse temperature distribution is 10% or less, the web up-down air volume ratio is 0.2-1 and the dry gas ratio is 30-250 J /. A technique of Kmol is described. Furthermore, preferable drying conditions are disclosed depending on the amount of residual solvent in drying in the tenter.
Specifically, after the web is peeled off from the support, the angle of the air blown from the air outlet is in the range of 30 to 150 ° with respect to the film plane until the amount of residual solvent in the web reaches 4% by mass. And when the wind speed distribution on the film surface located in the direction in which the drying gas is blown out is based on the upper limit value of the wind speed, the difference between the upper limit value and the lower limit value is within 20% of the upper limit value. When blowing out, drying the web, and when the residual solvent amount in the web is 70% by mass or more and 130% by mass or less, the wind speed on the web surface of the dry gas blown out from the blowing type dryer is 0.5 m. / Sec or more and 20 m / sec or less, and when the residual solvent amount is less than 70% by mass and 4% by mass or more, the drying gas blown out at a wind speed of 0.5 m / sec or more and 40 m / sec or less. When the temperature distribution of the drying gas in the width direction of the web is based on the upper limit value of the gas temperature, the difference between the upper limit value and the lower limit value should be within 10% of the upper limit value. When the solvent amount is 4% by mass or more and 200% by mass or less, the air flow ratio q of the dry gas blown out from the blow-out port of the blow-type dryer located above and below the web to be conveyed may be 0.2 ≦ q ≦ 1. Are listed. Furthermore, as a preferred embodiment, at least one kind of gas is used for the drying gas, the average specific heat is 31.0 J / K · mol or more and 250 J / K · mol or less, and the room temperature contained in the drying gas during drying. And the concentration of the liquid organic compound is dried with a drying gas having a saturated vapor pressure of 50% or less. These techniques may be employed in the present invention.

Japanese Patent Laid-Open No. 11-0777719 discloses that a tenter clip incorporates a heating portion in a TAC (cellulose triacetate) film manufacturing apparatus in order to prevent deterioration of flatness and coating due to generation of contaminants. The technology is described.
As a further preferred aspect of this technique, a device for removing foreign matter generated at the contact portion between the clip and the web after the tenter clip releases the web and again supports the web is provided, and the gas to be injected Alternatively, the foreign matter is removed using a liquid and a brush, the residual amount at the time of contact between the clip or pin and the web is 12% by mass or more and 50% by mass or less, and the surface temperature of the contact portion between the clip or pin and the web is It is disclosed that it is 60 ° or more and 200 ° or less (more preferably 80 ° or more and 120 ° or less), and this technique may be employed in the present invention.

  In addition, in JP-A-11-090943, in order to improve flatness, improve quality deterioration due to tearing in the tenter, and increase productivity, in the tenter clip, an arbitrary transport length Lt ( m) and the total length Ltt (m) in the conveyance direction of the portion where the clip of the tenter having the same length as Lt holds the web Lr = Ltt / Lt is 1.0 ≦ Lr ≦ 1 .99 is described. Further, as a preferred embodiment, a technique is disclosed in which a portion for holding a web is arranged without a gap when viewed from the web width direction, and this technique may be adopted in the present invention.

Japanese Patent Application Laid-Open No. 11-090944 discloses a plastic film manufacturing apparatus in front of a tenter entrance in order to improve flatness deterioration due to web sagging and introduction instability when a web is introduced into a tenter. Describes a technology having a sag suppressing device in the web width direction.
As a more preferable aspect of this technique, the sag suppressing device is a rotating roller that rotates in the direction range of 2 to 60 ° in the width direction, has an air intake device on the upper part of the web, and from below the web. Having a blower capable of blowing air is also disclosed, and this technique may be employed in the present invention.

  Japanese Patent Laid-Open No. 11-090945 discloses a TAC manufacturing method in which the web peeled from the support is angled with respect to the horizontal in order to prevent the deterioration of quality and sagging that hinders productivity. Is introduced to the tenter, and this technology may be employed in the present invention.

  JP-A-2000-289903 discloses a transporting apparatus that transports while applying tension in the width direction of the web when the film is peeled and has a solvent content of 50 to 12% by mass in order to produce a film having stable physical properties. , A web width detecting means, a web holding means, and a technique that has two or more variable bending points, calculates a web width from a detection signal in web width detection, and changes the position of the bending point This technique may be employed in the present invention.

Japanese Patent Application Laid-Open No. 2003-033933 discloses that the right and left sides of the web on the left and right sides near the entrance of the tenter are provided in order to improve clipping, prevent web breakage for a long period of time, and obtain a film with excellent quality. A web side edge curl prevention guide plate is disposed at least below the upper and lower side edges, and the web facing surface of the guide plate is arranged in the web conveying direction and the web. It is described that it comprises a contact metal part.
As a further preferable aspect of this technique, the web contact resin portion of the guide plate facing the web is disposed on the upstream side in the web conveyance direction, and the web contact metal portion is disposed on the downstream side. The step between the resin part and the metal part for web contact (including the inclination) is within 500 μm, and the distance in the width direction in contact with the web of the resin part for web contact of the guide plate and the web of the metal part for web contact is The distance between the web contact resin part of the guide plate and the web contact metal part of the web contact direction in the web conveyance direction is 5 to 120 mm, respectively, and the web contact resin part of the guide plate is 2 to 150 mm. , Provided on a metal guide substrate by surface resin processing or resin coating, the web contact resin portion of the guide plate is made of a single resin, the left and right sides of the web The distance between the web facing surfaces of the guide plates arranged above and below at the side edge is 3 to 30 mm, and between the web facing surfaces of the upper and lower guide plates at the left and right side edges of the web. The distance is increased in the width direction of the web and inward at a rate of 2 mm or more per width of 100 mm, and the upper and lower guide plates have a length of 10 to 300 mm at the left and right side edges of the web, respectively. And both upper and lower guide plates are arranged so as to be displaced back and forth along the web conveyance direction, and the distance of deviation between the upper and lower guide plates is −200 to +200 mm, The web facing surface of the upper guide plate is made of only resin or metal, the web contact resin portion of the guide plate is made of Teflon (registered trademark), and the web contact gold The genus part is made of stainless steel, the web facing surface of the guide plate or the surface roughness of the resin part for web contact and / or the metal part for web contact provided on this is 3 μm or less, etc. It is disclosed.
Further, it is also described that the installation position of the upper and lower guide plates for preventing web side edge curl generation is preferably between the peeling side end portion of the support and the tenter introduction portion, and more preferably installed near the tenter entrance. These techniques may be employed in the present invention.

Japanese Patent Application Laid-Open No. 11-048271 discloses a width stretching device at the time when the web has a solvent content of 50 to 12% by mass in order to prevent cutting and unevenness of the web during drying in the tenter. And a technique of applying a pressure of 0.2 to 10 KPa from both sides of the web with a pressurizing device when the solvent content of the web is 10% by mass or less.
As a more preferable embodiment of this technique, when applying the tension using a nip roll as a method of finishing applying the tension when the solvent content is 4% by mass or more and applying pressure from both sides of the web (film), a pair of nip rolls is used. It is also disclosed that about 1 to 8 pairs are preferable, and that the temperature when pressurizing is preferably 100 to 200 ° C., and this technique may be adopted in the present invention.

Japanese Patent Laid-Open No. 2002-036266 discloses a preferred embodiment of a technique for obtaining a high-quality thin tack having a thickness of 20 to 85 μm as a difference in tension acting on the web along the conveying direction before and after the tenter. Is 8 N / mm ² or less, a preheating step for preheating the web after the peeling step, a stretching step for stretching the web using a tenter after the preheating step, and after the stretching step, And a relaxation step for relaxing by an amount smaller than the stretching amount in the stretching step, and the temperature T ₁ in the preheating step and the stretching step is set to (glass transition temperature Tg-60) ° C. or more and relaxation. The temperature T ₂ in the process is set to (T ₁ -10) ° C. or less, and the stretch ratio of the web in the stretching process is 0 to 30% as a ratio to the web width immediately before entering the stretching process. In addition, it is disclosed that the stretching ratio of the web in the relaxation step is −10 to 10%, and this technique may be employed in the present invention.

  JP 2002-225054 A discloses that the residual solvent amount of the web after peeling is 10% by mass for the purpose of being excellent in thinness and dry weight with a dry film thickness of 10 to 60 μm and small durability. In the meantime, the both ends of the web are gripped with clips, the drying shrinkage is suppressed by holding the width, and / or the stretching is performed in the width direction, and the plane orientation degree S represented by the following formula (III) Forming a film of 0.0008 to 0.0020 (in the following formula (III), Nx is the refractive index in the direction of the largest refractive index in the plane of the film, and Ny is perpendicular to Nx in the plane) The refractive index in the direction, Nz refers to the refractive index in the film thickness direction of the film.), The time from casting to peeling is set to 30 to 90 seconds, and the web after peeling in the width direction and / or the longitudinal direction Stretching, etc. are disclosed. The may also be employed in the present invention.

S = {(Nx + Ny) / 2} −Nz... Formula (III)

  Japanese Patent Application Laid-Open No. 2002-341144 discloses a solution film-forming method having a stretching process in which the mass concentration of a retardation increasing agent has a higher optical distribution as it approaches the center in the film width direction in order to suppress optical unevenness. This technique may be employed in the present invention.

In addition, in JP-A-2003-071863, in order to obtain a film in which fogging does not occur, the draw ratio in the width direction is preferably 0 to 100%. It is described that 20% is more preferable, and 8 to 15% is most preferable.
On the other hand, in this publication, when used as a retardation film (optical compensation film), 10 to 40% is more preferable, 20 to 30% is most preferable, and Ro can be controlled by the draw ratio. It is disclosed that a higher value is preferable because the flatness of the finished film is excellent.
Furthermore, when the tenter is used, the residual solvent amount of the film is preferably 20 to 100% by mass at the start of the tenter, and drying is performed while the tenter is applied until the residual solvent amount of the film becomes 10% by mass or less. It is preferable that 5% by mass or less is more preferable.
Moreover, the drying temperature in the case of performing a tenter is preferably 30 to 150 ° C., more preferably 50 to 120 ° C., most preferably 70 to 100 ° C. However, it is also disclosed that the higher the drying temperature, the better the flatness of the film, and this technique may be adopted in the present invention.

Japanese Patent Laid-Open No. 2002-248639 discloses that a cellulose ester solution is continuously cast on a support in order to reduce vertical and horizontal dimensional fluctuations during storage under high temperature and high humidity conditions. In the method for producing a film to be peeled and dried, a technique for drying so that the drying shrinkage rate satisfies the following formula (IV) is described.
0 ≦ dry shrinkage (%) ≦ 0.1 × residual solvent amount when peeling (%) ··· formula (IV)

  As a more preferred embodiment of this technique, when the residual solvent amount of the cellulose ester film after peeling is in the range of 40 to 100% by mass, at least the residual solvent amount is set to 30 while holding both ends of the cellulose ester film by tenter conveyance. The amount of residual solvent at the tenter transport inlet of the cellulose ester film after peeling is 40 to 100% by weight, the amount of residual solvent at the outlet is 4 to 20% by weight, and the cellulose ester by tenter transport The tension for transporting the film increases from the entrance to the exit of the tenter transport, the tension for transporting the cellulose ester film by the tenter transport and the tension of the cellulose ester film in the width direction are substantially equal, etc. And this technology is adopted in the present invention. It may be.

  Japanese Patent Application Laid-Open No. 2000-239403 discloses a residual solvent ratio X at the time of peeling and a residual value when introduced into a tenter in order to obtain a film having a thin film thickness and excellent optical isotropy and flatness. It is disclosed that the film formation is performed with the relationship with the solvent ratio Y being in the range of 0.3X ≦ Y ≦ 0.9X, and this technique may be employed in the present invention.

  JP 2002-286933 A includes a method of stretching a film to be formed by casting, a method of stretching under heating conditions and a method of stretching under solvent-containing conditions. When stretching, it is preferable to stretch at a temperature below the glass transition point of the resin. On the other hand, when stretching a cast film under solvent-impregnated conditions, the once dried film is re-solvent. It is disclosed that the film can be impregnated with a solvent to be stretched, and this technique can be employed in the present invention.

<< Retardation raising agent >>
[Retardation increasing agent for controlling Rth]
The transparent support constituting the optical compensation film of the present invention contains a retardation increasing agent (Rth increasing agent) that selectively controls Rth.
Here, the Rth increasing agent of the present invention is added to the transparent support, among the general retardation increasing agents that increase Re and Rth of the transparent support by adding it to the transparent support. , Rth is a compound that selectively expresses Rth. For example, when the Re value and Rth value of the transparent support itself (transparent support to which no Rth increasing agent is added) are subtracted from the Re value and Rth value of the transparent support prepared by adding, It is a compound in which Rth expressed by the added compound (Rth raising agent) shows a predetermined value or more with respect to Re.
The Rth raising agent preferably has at least one absorption maximum at 250 nm or more, more preferably at least one absorption maximum at 250 or more and 360 nm or less, and at least one absorption maximum at 300 or more and 355 nm or less. Is more preferable.
By doing in this way, the difference of the Rth value in each wavelength of 630 nm, 550 nm, and 450 nm becomes large, and the color change is suppressed.

  Further, the Rth increasing agent contained in the transparent support constituting the optical compensation film of the present invention is preferably a compound having at least two aromatic rings.

  Moreover, it is preferable that the Rth raising agent contained in the transparent support which comprises the optical compensation film of this invention is chosen from the compound represented by the following general formula (II)-(V).

In the general formula (II), each R ¹² independently represents an aromatic ring or a heterocyclic ring having a substituent in at least one of the ortho position, the meta position, and the para position.
Moreover, X < ¹¹ > represents a single bond or NR < ¹³ >-each independently. Here, each R ¹³ independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an aryl group, or a heterocyclic group.

The aromatic ring represented by R ¹² is preferably phenyl or naphthyl, and particularly preferably phenyl. The aromatic ring represented by R ¹² may have at least one substituent at any substitution position. Examples of the substituent include a halogen atom, hydroxyl, cyano, nitro, carboxyl, alkyl group, alkenyl group, aryl group, alkoxy group, alkenyloxy group, aryloxy group, acyloxy group, alkoxycarbonyl group, alkenyloxycarbonyl group. , Aryloxycarbonyl group, sulfamoyl group, alkyl-substituted sulfamoyl group, alkenyl-substituted sulfamoyl group, aryl-substituted sulfamoyl group, sulfonamide group, carbamoyl, alkyl-substituted carbamoyl group, alkenyl-substituted carbamoyl group, aryl-substituted carbamoyl group, amide group, alkylthio group , An alkenylthio group, an arylthio group, and an acyl group.

The heterocyclic group represented by R ¹² preferably has aromaticity. The heterocycle having aromaticity is generally an unsaturated heterocycle, and a heterocycle having the largest number of double bonds is preferred. The heterocyclic ring is preferably a 5-membered ring, a 6-membered ring or a 7-membered ring, more preferably a 5-membered ring or a 6-membered ring, and most preferably a 6-membered ring. The hetero atom of the heterocyclic ring is preferably a nitrogen atom, a sulfur atom or an oxygen atom, and particularly preferably a nitrogen atom. As the heterocyclic ring having aromaticity, a pyridine ring (2-pyridyl or 4-pyridyl as the heterocyclic group) is particularly preferable. The heterocyclic group may have a substituent. Examples of the substituent of the heterocyclic group are the same as the examples of the substituent of the aryl moiety.
When X ¹¹ is a single bond, the heterocyclic group is preferably a heterocyclic group having a free valence on the nitrogen atom. The heterocyclic group having a free valence on the nitrogen atom is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring, and a 5-membered ring. Is most preferred. The heterocyclic group may have a plurality of nitrogen atoms. In addition, the heterocyclic group may have a hetero atom other than the nitrogen atom (eg, O, S). Examples of heterocyclic groups having free valences on nitrogen atoms are shown below.

In the general formula ^{(II), X 11} represents a single bond or ^{NR 13} - represents a. R ¹³ independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an aryl group, or a heterocyclic group.
The alkyl group represented by R ¹³ may be a cyclic alkyl group or a chain alkyl group, but a chain alkyl group is preferable, and a linear alkyl group is more preferable than a branched chain alkyl group. preferable. The number of carbon atoms in the alkyl group is preferably 1-30, more preferably 1-20, still more preferably 1-10, still more preferably 1-8, and 1-6. Most preferred. The alkyl group may have a substituent. Examples of the substituent include a halogen atom, an alkoxy group (for example, methoxy group, ethoxy group) and an acyloxy group (for example, acryloyloxy group, methacryloyloxy group).

The alkenyl group represented by R ¹³ may be a cyclic alkenyl group or a chain alkenyl group, but is preferably a chain alkenyl group, and is a straight chain alkenyl group rather than a branched chain alkenyl group. More preferably it represents a group. The number of carbon atoms in the alkenyl group is preferably 2 to 30, more preferably 2 to 20, still more preferably 2 to 10, still more preferably 2 to 8, 6 is most preferred. The alkenyl group may have a substituent. Examples of the substituent are the same as those of the alkyl group described above.
The aromatic ring group and heterocyclic group represented by R ¹³ are the same as the aromatic ring and heterocyclic ring represented by R ¹² , and the preferred range is also the same. The aromatic ring group and the heterocyclic group may further have a substituent, and examples of the substituent are the same as those of the aromatic ring and heterocyclic ring of R ¹² .

  Below, the specific example of Rth raising agent represented by general formula (II) used by this invention is shown. Several R shown in the same structural formula in each exemplary compound means the same group. The definition of R is shown after the formula together with the specific example number.

II- (1) phenyl II- (2) 3-ethoxycarbonylphenyl II- (3) 3-butoxyphenyl II- (4) m-biphenylyl II- (5) 3-phenylthiophenyl II- (6) 3- Chlorophenyl II- (7) 3-benzoylphenyl II- (8) 3-acetoxyphenyl II- (9) 3-benzoyloxyphenyl II- (10) 3-phenoxycarbonylphenyl II- (11) 3-methoxyphenyl II- (12) 3-anilinophenyl II- (13) 3-isobutyrylaminophenyl II- (14) 3-phenoxycarbonylaminophenyl II- (15) 3- (3-ethylureido) phenyl II- (16) 3- (3,3-Diethylureido) phenyl II- (17) 3-methylphenyl II- (18) 3-phenoxy Phenyl II- (19) 3- hydroxyphenyl

II- (20) 4-Ethoxycarbonylphenyl II- (21) 4-butoxyphenyl II- (22) p-biphenylyl II- (23) 4-phenylthiophenyl II- (24) 4-chlorophenyl II- (25) 4-benzoylphenyl II- (26) 4-acetoxyphenyl II- (27) 4-benzoyloxyphenyl II- (28) 4-phenoxycarbonylphenyl II- (29) 4-methoxyphenyl II- (30) 4-ani Linophenyl II- (31) 4-isobutyrylaminophenyl II- (32) 4-phenoxycarbonylaminophenyl II- (33) 4- (3-ethylureido) phenyl II- (34) 4- (3,3 -Diethylureido) phenyl II- (35) 4-methylphenyl II- (36) 4-phenoxyv Sulfonyl II- (37) 4-hydroxyphenyl

II- (38) 3,4-diethoxycarbonylphenyl II- (39) 3,4-dibutoxyphenyl II- (40) 3,4-diphenylphenyl II- (41) 3,4-diphenylthiophenyl II- (42) 3,4-dichlorophenyl II- (43) 3,4-dibenzoylphenyl II- (44) 3,4-diacetoxyphenyl II- (45) 3,4-dibenzoyloxyphenyl II- (46) 3,4-diphenoxycarbonylphenyl II- (47) 3,4-dimethoxyphenyl II- (48) 3,4-dianilinophenyl II- (49) 3,4-dimethylphenyl II- (50) 3,4 -Diphenoxyphenyl II- (51) 3,4-dihydroxyphenyl II- (52) 2-naphthyl

II- (53) 3,4,5-triethoxycarbonylphenyl II- (54) 3,4,5-tributoxyphenyl II- (55) 3,4,5-triphenylphenyl II- (56) 3 4,5-triphenylthiophenyl II- (57) 3,4,5-trichlorophenyl II- (58) 3,4,5-tribenzoylphenyl II- (59) 3,4,5-triacetoxyphenyl II -(60) 3,4,5-tribenzoyloxyphenyl II- (61) 3,4,5-triphenoxycarbonylphenyl II- (62) 3,4,5-trimethoxyphenyl II- (63) 3 4,5-trianilinophenyl II- (64) 3,4,5-trimethylphenyl II- (65) 3,4,5-triphenoxyphenyl II- (66) 3,4,5-trihi Rokishifeniru

II- (67) phenyl II- (68) 3-ethoxycarbonylphenyl II- (69) 3-butoxyphenyl II- (70) m-biphenylyl II- (71) 3-phenylthiophenyl II- (72) 3- Chlorophenyl II- (73) 3-benzoylphenyl II- (74) 3-acetoxyphenyl II- (75) 3-benzoyloxyphenyl II- (76) 3-phenoxycarbonylphenyl II- (77) 3-methoxyphenyl II- (78) 3-anilinophenyl II- (79) 3-isobutyrylaminophenyl II- (80) 3-phenoxycarbonylaminophenyl II- (81) 3- (3-ethylureido) phenyl II- (82) 3- (3,3-Diethylureido) phenyl II- (83) 3-methylphenyl II- ( 4) 3-phenoxyphenyl II- (85) 3-hydroxyphenyl

II- (86) 4-Ethoxycarbonylphenyl II- (87) 4-butoxyphenyl II- (88) p-biphenylyl II- (89) 4-phenylthiophenyl II- (90) 4-chlorophenyl II- (91) 4-benzoylphenyl II- (92) 4-acetoxyphenyl II- (93) 4-benzoyloxyphenyl II- (94) 4-phenoxycarbonylphenyl II- (95) 4-methoxyphenyl II- (96) 4-ani Linophenyl II- (97) 4-isobutyrylaminophenyl II- (98) 4-phenoxycarbonylaminophenyl II- (99) 4- (3-ethylureido) phenyl II- (100) 4- (3,3 -Diethylureido) phenyl II- (101) 4-methylphenyl II- (102) 4-pheno Shifeniru II- (103) 4-hydroxyphenyl

II- (104) 3,4-diethoxycarbonylphenyl II- (105) 3,4-dibutoxyphenyl II- (106) 3,4-diphenylphenyl II- (107) 3,4-diphenylthiophenyl II- (108) 3,4-dichlorophenyl II- (109) 3,4-dibenzoylphenyl II- (110) 3,4-diacetoxyphenyl II- (111) 3,4-dibenzoyloxyphenyl II- (112) 3,4-diphenoxycarbonylphenyl II- (113) 3,4-dimethoxyphenyl II- (114) 3,4-dianilinophenyl II- (115) 3,4-dimethylphenyl II- (116) 3,4 -Diphenoxyphenyl II- (117) 3,4-dihydroxyphenyl II- (118) 2-naphthyl

II- (119) 3,4,5-triethoxycarbonylphenyl II- (120) 3,4,5-tributoxyphenyl II- (121) 3,4,5-triphenylphenyl II- (122) 3 4,5-triphenylthiophenyl II- (123) 3,4,5-trichlorophenyl II- (124) 3,4,5-tribenzoylphenyl II- (125) 3,4,5-triacetoxyphenyl II -(126) 3,4,5-tribenzoyloxyphenyl II- (127) 3,4,5-triphenoxycarbonylphenyl II- (128) 3,4,5-trimethoxyphenyl II- (129) 3 4,5-trianilinophenyl II- (130) 3,4,5-trimethylphenyl II- (131) 3,4,5-triphenoxyphenyl II- 132) 3,4,5-hydroxyphenyl

II- (133) phenyl II- (134) 4-butylphenyl II- (135) 4- (2-methoxy-2-ethoxyethyl) phenyl II- (136) 4- (5-nonenyl) phenyl II- (137 ) P-biphenylyl II- (138) 4-ethoxycarbonylphenyl II- (139) 4-butoxyphenyl II- (140) 4-methylphenyl II- (141) 4-chlorophenyl II- (142) 4-phenylthiophenyl II- (143) 4-benzoylphenyl II- (144) 4-acetoxyphenyl II- (145) 4-benzoyloxyphenyl II- (146) 4-phenoxycarbonylphenyl II- (147) 4-methoxyphenyl II- ( 148) 4-anilinophenyl II- (149) 4-isobutyrylamino Enyl II- (150) 4-phenoxycarbonylaminophenyl II- (151) 4- (3-ethylureido) phenyl II- (152) 4- (3,3-diethylureido) phenyl II- (153) 4-phenoxy Phenyl II- (154) 4-hydroxyphenyl

II- (155) 3-Butylphenyl II- (156) 3- (2-methoxy-2-ethoxyethyl) phenyl II- (157) 3- (5-nonenyl) phenyl II- (158) m-biphenylyl II- (159) 3-ethoxycarbonylphenyl II- (160) 3-butoxyphenyl II- (161) 3-methylphenyl II- (162) 3-chlorophenyl II- (163) 3-phenylthiophenyl II- (164) 3 -Benzoylphenyl II- (165) 3-acetoxyphenyl II- (166) 3-benzoyloxyphenyl II- (167) 3-phenoxycarbonylphenyl II- (168) 3-methoxyphenyl II- (169) 3-anilino Phenyl II- (170) 3-isobutyrylaminophenyl II- (171) -Phenoxycarbonylaminophenyl II- (172) 3- (3-ethylureido) phenyl II- (173) 3- (3,3-diethylureido) phenyl II- (174) 3-phenoxyphenyl II- (175) 3 -Hydroxyphenyl

II- (176) 2-Butylphenyl II- (177) 2- (2-methoxy-2-ethoxyethyl) phenyl II- (178) 2- (5-nonenyl) phenyl II- (179) o-biphenylyl II- (180) 2-ethoxycarbonylphenyl II- (181) 2-butoxyphenyl II- (182) 2-methylphenyl II- (183) 2-chlorophenyl II- (184) 2-phenylthiophenyl II- (185) 2 -Benzoylphenyl II- (186) 2-acetoxyphenyl II- (187) 2-benzoyloxyphenyl II- (188) 2-phenoxycarbonylphenyl II- (189) 2-methoxyphenyl II- (190) 2-anilino Phenyl II- (191) 2-isobutyrylaminophenyl II- (192) -Phenoxycarbonylaminophenyl II- (193) 2- (3-ethylureido) phenyl II- (194) 2- (3,3-diethylureido) phenyl II- (195) 2-phenoxyphenyl II- (196) 2 -Hydroxyphenyl

II- (197) 3,4-dibutylphenyl II- (198) 3,4-di (2-methoxy-2-ethoxyethyl) phenyl II- (199) 3,4-diphenylphenyl II- (200) 3 4-diethoxycarbonylphenyl II- (201) 3,4-didodecyloxyphenyl II- (202) 3,4-dimethylphenyl II- (203) 3,4-dichlorophenyl II- (204) 3,4-di Benzoylphenyl II- (205) 3,4-diacetoxyphenyl II- (206) 3,4-dimethoxyphenyl II- (207) 3,4-di-N-methylaminophenyl II- (208) 3,4 Diisobutyrylaminophenyl II- (209) 3,4-diphenoxyphenyl II- (210) 3,4-dihydroxyphenyl

II- (211) 3,5-dibutylphenyl II- (212) 3,5-di (2-methoxy-2-ethoxyethyl) phenyl II- (213) 3,5-diphenylphenyl II- (214) 3 5-diethoxycarbonylphenyl II- (215) 3,5-didodecyloxyphenyl II- (216) 3,5-dimethylphenyl II- (217) 3,5-dichlorophenyl II- (218) 3,5-di Benzoylphenyl II- (219) 3,5-diacetoxyphenyl II- (220) 3,5-dimethoxyphenyl II- (221) 3,5-di-N-methylaminophenyl II- (222) 3,5- Diisobutyrylaminophenyl II- (223) 3,5-diphenoxyphenyl II- (224) 3,5-dihydroxyphenyl

II- (225) 2,4-dibutylphenyl II- (226) 2,4-di (2-methoxy-2-ethoxyethyl) phenyl II- (227) 2,4-diphenylphenyl II- (228) 2, 4-diethoxycarbonylphenyl II- (229) 2,4-didodecyloxyphenyl II- (230) 2,4-dimethylphenyl II- (231) 2,4-dichlorophenyl II- (232) 2,4-di Benzoylphenyl II- (233) 2,4-diacetoxyphenyl II- (234) 2,4-dimethoxyphenyl II- (235) 2,4-di-N-methylaminophenyl II- (236) 2,4- Diisobutyrylaminophenyl II- (237) 2,4-diphenoxyphenyl II- (238) 2,4-dihydroxyphenyl

II- (239) 2,3-dibutylphenyl II- (240) 2,3-di (2-methoxy-2-ethoxyethyl) phenyl II- (241) 2,3-diphenylphenyl II- (242) 2, 3-diethoxycarbonylphenyl II- (243) 2,3-didodecyloxyphenyl II- (244) 2,3-dimethylphenyl II- (245) 2,3-dichlorophenyl II- (246) 2,3-di Benzoylphenyl II- (247) 2,3-diacetoxyphenyl II- (248) 2,3-dimethoxyphenyl II- (249) 2,3-di-N-methylaminophenyl II- (250) 2,3- Diisobutyrylaminophenyl II- (251) 2,3-diphenoxyphenyl II- (252) 2,3-dihydroxyphenyl

II- (253) 2,6-dibutylphenyl II- (254) 2,6-di (2-methoxy-2-ethoxyethyl) phenyl II- (255) 2,6-diphenylphenyl II- (256) 2, 6-diethoxycarbonylphenyl II- (257) 2,6-didodecyloxyphenyl II- (258) 2,6-dimethylphenyl II- (259) 2,6-dichlorophenyl II- (260) 2,6-di Benzoylphenyl II- (261) 2,6-diacetoxyphenyl II- (262) 2,6-dimethoxyphenyl II- (263) 2,6-di-N-methylaminophenyl II- (264) 2,6- Diisobutyrylaminophenyl II- (265) 2,6-diphenoxyphenyl II- (266) 2,6-dihydroxyphenyl

II- (267) 3,4,5-tributylphenyl II- (268) 3,4,5-tri (2-methoxy-2-ethoxyethyl) phenyl II- (269) 3,4,5-triphenylphenyl II- (270) 3,4,5-triethoxycarbonylphenyl II- (271) 3,4,5-tridodecyloxyphenyl II- (272) 3,4,5-trimethylphenyl II- (273) 3 4,5-trichlorophenyl II- (274) 3,4,5-tribenzoylphenyl II- (275) 3,4,5-triacetoxyphenyl II- (276) 3,4,5-trimethoxyphenyl II- (277) 3,4,5-Tri-N-methylaminophenyl II- (278) 3,4,5-triisobutyrylaminophenyl II- (279) 3,4,5- Li phenoxyphenyl II- (280) 3,4,5-trihydroxy-phenyl

II- (281) 2,4,6-tributylphenyl II- (282) 2,4,6-tri (2-methoxy-2-ethoxyethyl) phenyl II- (283) 2,4,6-triphenylphenyl II- (284) 2,4,6-triethoxycarbonylphenyl II- (285) 2,4,6-tridodecyloxyphenyl II- (286) 2,4,6-trimethylphenyl II- (287) 2, 4,6-trichlorophenyl II- (288) 2,4,6-tribenzoylphenyl II- (289) 2,4,6-triacetoxyphenyl II- (290) 2,4,6-trimethoxyphenyl II- (291) 2,4,6-Tri-N-methylaminophenyl II- (292) 2,4,6-triisobutyrylaminophenyl II- (293) 2,4,6- Li phenoxyphenyl II- (294) 2,4,6-trihydroxyphenyl

II- (295) pentafluorophenyl II- (296) pentachlorophenyl II- (297) pentamethoxyphenyl II- (298) 6-N-methylsulfamoyl-8-methoxy-2-naphthyl II- (299) 5 -N-methylsulfamoyl-2-naphthyl II- (300) 6-N-phenylsulfamoyl-2-naphthyl II- (301) 5-ethoxy-7-N-methylsulfamoyl-2-naphthyl II -(302) 3-methoxy-2-naphthyl II- (303) 1-ethoxy-2-naphthyl II- (304) 6-N-phenylsulfamoyl-8-methoxy-2-naphthyl II- (305) 5 -Methoxy-7-N-phenylsulfamoyl-2-naphthyl II- (306) 1- (4-methylphenyl) -2-naphthyl II (307) 6,8-Di-N-methylsulfamoyl-2-naphthyl II- (308) 6-N-2-acetoxyethylsulfamoyl-8-methoxy-2-naphthyl II- (309) 5- Acetoxy-7-N-phenylsulfamoyl-2-naphthyl II- (310) 3-benzoyloxy-2-naphthyl

II- (311) 5-acetylamino-1-naphthyl II- (312) 2-methoxy-1-naphthyl II- (313) 4-phenoxy-1-naphthyl II- (314) 5-N-methylsulfamoyl -1-Naphtyl II- (315) 3-N-methylcarbamoyl-4-hydroxy-1-naphthyl II- (316) 5-methoxy-6-N-ethylsulfamoyl-1-naphthyl II- (317) 7 -Tetradecyloxy-1-naphthyl II- (318) 4- (4-methylphenoxy) -1-naphthyl II- (319) 6-N-methylsulfamoyl-1-naphthyl II- (320) 3-N , N-dimethylcarbamoyl-4-methoxy-1-naphthyl II- (321) 5-methoxy-6-N-benzylsulfamoyl-1-naphthyl II- (32 ) 3,6-di -N- phenyl sulfamoyl-1-naphthyl

II- (323) methyl II- (324) ethyl II- (325) butyl II- (326) octyl II- (327) dodecyl II- (328) 2-butoxy-2-ethoxyethyl II- (329) benzyl II -(330) 4-methoxybenzyl

II- (331) methyl II- (332) phenyl II- (333) butyl

  The compound represented by general formula (III) is demonstrated below.

In the general formula (III), R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ each independently represent a hydrogen atom or a substituent.
R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ are each represented by an alkyl group (preferably having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably An alkyl group having 1 to 20 carbon atoms, for example, methyl group, ethyl group, isopropyl group, tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl Group), an alkenyl group (preferably an alkenyl group having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, and particularly preferably 2 to 20 carbon atoms, such as a vinyl group, an allyl group, 2 -Butenyl group, 3-pentenyl group and the like), alkynyl group (preferably having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, and particularly preferably 2 carbon atoms). -20 alkynyl group, for example, propargyl group, 3-pentynyl group, etc., aryl group (preferably 6-30 carbon atoms, more preferably 6-20 carbon atoms, particularly preferably 6-6 carbon atoms). 12 aryl groups, for example, phenyl group, p-methylphenyl group, naphthyl group and the like, substituted or unsubstituted amino group (preferably having 0 to 40 carbon atoms, more preferably 0 to 30 carbon atoms). And particularly preferably an amino group having 0 to 20 carbon atoms, such as an unsubstituted amino group, a methylamino group, a dimethylamino group, a diethylamino group, and an anilino group).

  An alkoxy group (preferably an alkoxy group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, and a butoxy group). Aryloxy group (preferably an aryloxy group having 6 to 40 carbon atoms, more preferably 6 to 30 carbon atoms, particularly preferably 6 to 20 carbon atoms, and examples thereof include a phenyloxy group and a 2-naphthyloxy group. An acyl group (preferably an acyl group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, and particularly preferably 1 to 20 carbon atoms, such as an acetyl group, a benzoyl group, a formyl group, and a pivaloyl group. Etc.), an alkoxycarbonyl group (preferably having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, and particularly preferably carbon number) To 20 alkoxy groups such as methoxycarbonyl group and ethoxycarbonyl group), aryloxycarbonyl groups (preferably having 7 to 40 carbon atoms, more preferably having 7 to 30 carbon atoms, and particularly preferably carbon atoms). An aryloxycarbonyl group having 7 to 20 carbon atoms, such as a phenyloxycarbonyl group, and an acyloxy group (preferably having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, and particularly preferably carbon number). 2-20 acyloxy groups such as an acetoxy group and a benzoyloxy group).

  An acylamino group (preferably an acylamino group having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, particularly preferably 2 to 20 carbon atoms, such as an acetylamino group and a benzoylamino group), alkoxycarbonyl An amino group (preferably an alkoxycarbonylamino group having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, particularly preferably 2 to 20 carbon atoms, such as a methoxycarbonylamino group), aryloxy Carbonylamino group (preferably an aryloxycarbonylamino group having 7 to 40 carbon atoms, more preferably 7 to 30 carbon atoms, particularly preferably 7 to 20 carbon atoms, such as a phenyloxycarbonylamino group) Sulfonylamino group (preferably having 1 to 40 carbon atoms, more preferred Or a sulfonylamino group having 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, such as a methanesulfonylamino group and a benzenesulfonylamino group, and a sulfamoyl group (preferably having a carbon number of 0 to 40). More preferably, it is a sulfamoyl group having 0 to 30 carbon atoms, particularly preferably 0 to 20 carbon atoms, and examples thereof include a sulfamoyl group, a methylsulfamoyl group, a dimethylsulfamoyl group, and a phenylsulfamoyl group. ), A carbamoyl group (preferably a carbamoyl group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, for example, an unsubstituted carbamoyl group, a methylcarbamoyl group, diethyl A carbamoyl group, a phenylcarbamoyl group, etc.).

  An alkylthio group (preferably having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, such as a phenylthio group), a sulfonyl group (preferably having 1 to 1 carbon atoms). 40, more preferably a sulfonyl group having 1 to 30 carbon atoms, particularly preferably a sulfonyl group having 1 to 20 carbon atoms, such as a mesyl group and a tosyl group, and a sulfinyl group (preferably having a carbon number of 1 to 40, more Preferably it is C1-C30, Most preferably, it is C1-C20 sulfinyl group, for example, a methane sulfinyl group, a benzene sulfinyl group, etc., a ureido group (preferably C1-C40, more preferable) Is a ureido group having 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, such as an unsubstituted ureido group or methylurea. And phosphoric acid amide groups (preferably having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, and particularly preferably 1 to 20 carbon atoms), For example, a diethylphosphoric acid amide group, a phenylphosphoric acid amide group etc. are mentioned), a hydroxy group, a mercapto group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a cyano group, a sulfo group, a carboxyl group , A nitro group, a 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 heterocyclic group having a heteroatom such as a sulfur atom, such as an imidazolyl group, a pyridyl group, a quinolyl group, a furyl group, a piperidyl group Morpholino group, benzoxazolyl group, benzimidazolyl group, benzthiazolyl group, 1,3,5-triazyl group, etc.), silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms). Particularly preferred is a silyl group having 3 to 24 carbon atoms, and examples thereof include a trimethylsilyl group and a triphenylsilyl group. 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.

Examples of the substituent represented by R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ include an alkyl group, an aryl group, a substituted or unsubstituted amino group, an alkoxy group, an alkylthio group, or a halogen atom. preferable.

  Although the specific example of a compound represented by general formula (III) below is given, it is not limited to these.

The compound represented by general formula (IV) is demonstrated below.
In the general formula (IV), Q ⁷¹ represents a nitrogen-containing aromatic heterocycle, and Q ⁷² represents an aromatic ring.
Similarly, the general formula (IV), Q ⁷¹ represents a nitrogen-containing heterocycle direction aromatic, preferably nitrogen-containing aromatic heterocyclic 5- to 7-membered, nitrogen-containing aromatic heterocyclic 5-6 membered More preferred.

  Examples of the nitrogen-containing aromatic heterocycle include imidazole, pyrazole, triazole, tetrazole, thiazole, oxazole, selenazole, benzotriazole, benzothiazole, benzoxazole, benzoselenazole, thiadiazole, oxadiazole, naphthothiazole, naphthoxazole, Each ring such as azabenzimidazole, purine, pyridine, pyrazine, pyrimidine, pyridazine, triazine, triazaindene, tetrazaindene and the like is preferable, triazine and a 5-membered nitrogen-containing aromatic heterocycle are more preferable, specifically 1,3,5-triazine, imidazole, pyrazole, triazole, tetrazole, thiazole, oxazole, benzotriazole, benzothiazole, benzoxazole, thiadia Lumpur, each ring are preferred, such as oxadiazole, 1,3,5-triazine ring and a benzotriazole ring is particularly preferred.

Nitrogen-containing aromatic heterocyclic ring represented by Q ⁷¹ may have a substituent, and the substituent may be the substituent T described later. In addition, when there are a plurality of substituents, each may be condensed to form a ring.

Q ⁷² represents an aromatic ring. Aromatic ring represented by Q ⁷² may be an aromatic hetero ring in the aromatic hydrocarbon ring. These may be monocyclic or may form a condensed ring with another ring. The aromatic hydrocarbon ring is preferably a monocyclic or bicyclic aromatic hydrocarbon ring having 6 to 30 carbon atoms (for example, a benzene ring, a naphthalene ring, etc.), and an aromatic hydrocarbon having 6 to 20 carbon atoms. A ring is more preferable, an aromatic hydrocarbon ring having 6 to 12 carbon atoms is further preferable, and a benzene ring is particularly preferable.

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

The aromatic ring represented by Q ^72, an aromatic hydrocarbon ring is preferably a naphthalene ring, more preferably a benzene ring, a benzene ring is particularly preferred. Q ⁷² may further have a substituent, and the following substituent T is preferred.
Examples of the substituent T include alkyl groups (preferably those having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms such as a methyl group, an ethyl group, an isopropyl group, and t-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, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8, for example, vinyl group, allyl group, 2-butenyl group, 3-pentenyl group, etc.), alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms). Yes, for example, propargyl group, 3-pentynyl group, etc., aryl group (preferably 6-30 carbon atoms, more preferably 6-20, particularly preferably 6-1) For example, a phenyl group, a biphenyl group, a naphthyl group, etc.), an amino group (preferably having a carbon number of 0 to 20, more preferably 0 to 10, particularly preferably 0 to 6, such as an amino group, a methylamino group, A dimethylamino group, a diethylamino group, a dibenzylamino group, etc.), an alkoxy group (preferably having a carbon number of 1-20, more preferably 1-12, particularly preferably 1-8, for example, a methoxy group, an ethoxy group, a butoxy group. Etc.), an aryloxy group (preferably having 6 to 20 carbon atoms, 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 The number is 1 to 20, more preferably 1 to 16, and particularly preferably 1 to 12. For example, acetyl group, benzoyl group, formyl group, A valoyl group), an alkoxycarbonyl group (preferably having a carbon number of 2-20, more preferably 2-16, particularly preferably 2-12, such as a methoxycarbonyl group, an ethoxycarbonyl group, etc.), an aryloxycarbonyl group (preferably Has 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 10 carbon atoms, such as a phenyloxycarbonyl group, an acyloxy group (preferably 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly Preferably it is 2-10, for example, an acetoxy group, a benzoyloxy group, etc.) etc. are mentioned.

  Other examples of the substituent T include an acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, and particularly preferably 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 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms such as a methoxycarbonylamino group), an aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms). , More preferably 7 to 16, particularly preferably 7 to 12, for example, phenyloxycarbonylamino group, etc., sulfonylamino group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16, particularly preferably 1 to 1). 12 such as methanesulfonylamino group, benzenesulfonylamino group, etc.), sulfamo Ru group (preferably having 0 to 20 carbon atoms, more preferably 0 to 16 carbon atoms, particularly preferably 0 to 12 carbon atoms such as sulfamoyl group, methylsulfamoyl group, dimethylsulfamoyl group, phenylsulfamoyl group, etc.) A carbamoyl group (preferably having a carbon number of 1-20, more preferably 1-16, particularly preferably 1-12, such as a carbamoyl group, a methylcarbamoyl group, a diethylcarbamoyl group, a phenylcarbamoyl group, etc.), an alkylthio group (preferably Has 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as a methylthio group and an ethylthio group, and an arylthio group (preferably 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, Particularly preferred are 6 to 12, for example, phenylthio group and the like, and sulfonyl group (preferably Or 1 to 16 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 12 carbon atoms such as a mesyl group and a tosyl group.), A sulfinyl group (preferably 1 to 20 carbon atoms, more preferably Is 1 to 16, particularly preferably 1 to 12, for example, methanesulfinyl group, benzenesulfinyl group, etc.), ureido group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms). For example, ureido group, methylureido group, phenylureido group, etc.), phosphoric acid amide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16, particularly preferably 1 to 12, such as diethyl phosphoric acid amide. , Phenyl phosphoric acid amide, etc.).

  Furthermore, as the substituent T, other than that, hydroxy group, mercapto group, halogen atom (for example, 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 a carbon number of 1-30, more preferably 1-12, and examples of the heteroatom include a nitrogen atom, an oxygen atom, a sulfur atom, specifically Is, for example, imidazolyl group, pyridyl group, quinolyl group, furyl group, piperidyl group, morpholino group, benzoxazolyl group, benzimidazolyl group, benzthiazolyl group, etc.), silyl group (preferably having 3 to 40 carbon atoms, more preferably Is 3 to 30, particularly preferably 3 to 24, such as trimethylsilyl group and triphenylsilyl group. ), And the like.

  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.

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

The compound represented by general formula (V) is demonstrated below.
However, in the general formula ^{(V), Q 81} and ^{Q 82} represents an aromatic ring each ^{independently, X 81} is ^NR 81 ^{(R 81} represents a hydrogen atom or a substituent) represents an oxygen atom or a sulfur atom Represents.
The aromatic hydrocarbon ring represented by Q ⁸¹ and Q ⁸² is preferably a monocyclic or bicyclic aromatic hydrocarbon ring having 6 to 30 carbon atoms (for example, a benzene ring or a naphthalene ring), It is preferably an aromatic hydrocarbon ring having 6 to 20 carbon atoms, more preferably an aromatic hydrocarbon ring having 6 to 12 carbon atoms, and particularly preferably a benzene ring.

The aromatic heterocycle represented by Q ⁸¹ and Q ⁸² is preferably an aromatic heterocycle containing at least one of an oxygen atom, a nitrogen atom or a sulfur atom. Specific examples of the aromatic heterocycle include, for example, furan, pyrrole, thiophene, imidazole, pyrazole, pyridine, pyrazine, pyridazine, triazole, triazine, indole, indazole, purine, thiazoline, thiazole, thiadiazole, oxazoline, oxazole, oxadi Examples include azole, quinoline, isoquinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, acridine, phenanthroline, phenazine, tetrazole, benzimidazole, benzoxazole, benzothiazole, benzotriazole, and tetrazaindene. As the aromatic heterocycle, a pyridine ring, a triazine ring, and a quinoline ring are preferable.

The aromatic ring represented by Q ⁸¹ and Q ⁸² is preferably an aromatic hydrocarbon ring, more preferably an aromatic hydrocarbon ring having 6 to 10 carbon atoms, and a substituted or unsubstituted benzene. More preferably, it is a ring.

Q ⁸¹ and Q ⁸² may further have a substituent. As the substituent, the above-described substituent T is preferable, but the substituent does not include a carboxylic acid, a sulfonic acid, or a quaternary ammonium salt. Further, if possible, substituents may be linked to form a ring structure.

X ⁸¹ represents NR ⁸¹ (R ⁸¹ represents a hydrogen atom or a substituent, and the above substituent T can be applied as the substituent), an oxygen atom or a sulfur atom. X ⁸¹ is preferably NR ⁸¹ (preferably R ⁸¹ is an acyl group or a sulfonyl group, and these substituents may be further substituted) or an oxygen atom, and more preferably an oxygen atom.

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

  The Rth raising agent used in the present invention is preferably a compound represented by the general formulas (II) and (III). Moreover, it is also preferably used to mix the compound represented by the general formula (IV) with the compound represented by the general formulas (II) and (III).

  The addition amount of the Rth raising agent (the compounds represented by the general formulas (II) to (V)) used in the present invention is preferably 2.0 to 30% by mass with respect to the base polymer of the film, respectively. 5-20 mass% is more preferable, and 2.5-10 mass% is still more preferable. When using 2 or more types, it is preferable that the total amount satisfy | fills the range of the said addition amount.

  The Rth increasing agent used in the present invention preferably exhibits liquid crystallinity. It is more preferable to exhibit liquid crystallinity (having thermotropic liquid crystallinity) by heating, and it is preferable to exhibit liquid crystallinity in a temperature range of 100 to 300 ° C. The liquid crystal phase is preferably a columnar phase, a nematic phase, or a smectic phase, and more preferably a columnar phase.

  The compound of the general formula (I) and the Rth raising agent may be added simultaneously with the dissolution of the base polymer of the film, or may be added to the dope after dissolution. In particular, a mode in which a UV absorber solution is added to the dope immediately before casting using a static mixer or the like is preferable because the spectral absorption characteristics can be easily adjusted.

[Retardation increasing agent for controlling Re]
In order to control the absolute value of Re of the protective film (optical compensation film) of the present invention, a compound having a maximum absorption wavelength (λ _max ) shorter than 250 nm in the ultraviolet absorption spectrum of the solution is used as a retardation increasing agent. It is preferable.
By using such a compound, the absolute value can be controlled without substantially changing the wavelength dependence of Re in the visible region.
In addition, from the viewpoint of the function of the retardation increasing agent, a rod-like compound is preferable, preferably having at least one aromatic ring, and more preferably having at least two aromatic rings.
The rod-shaped compound preferably has a linear molecular structure. The linear molecular structure means that the molecular structure of the rod-shaped compound is linear in the thermodynamically most stable structure.
The thermodynamically most stable structure can be obtained by crystal structure analysis or molecular orbital calculation.
For example, molecular orbital calculation is performed using molecular orbital calculation software (eg, WinMOPAC2000, manufactured by Fujitsu Limited), and a molecular structure that minimizes the heat of formation of a compound can be obtained.
Here, the molecular structure being linear means that the angle of the molecular structure is 140 ° or more in the thermodynamically most stable structure obtained by calculation as described above.
In addition, it is preferable that the addition amount of a retardation raising agent is 0.1-30 mass% with respect to the total solid of a polymer, and it is still more preferable that it is 0.5-20 mass%.

[Humidity dependency improver]
In the transparent support of the present invention, it is preferable to use a humidity dependency improving agent as an additive for reducing fluctuations in Re and Rth with respect to changes in environmental humidity.
The humidity dependency improver is preferably a compound having at least a plurality of hydrogen bonding groups in one molecule, and the hydrogen bonding group may be selected from a hydroxyl group, an amino group, a thiol group, and a carboxylic acid group. More preferably, it is particularly preferably selected from a hydroxyl group and a carboxylic acid group.
Moreover, it is preferable to have a plurality of different functional groups in one molecule.
The humidity-dependent improving agent preferably contains 1 to 2 aromatic rings as a mother nucleus, and the value obtained by dividing the number of functional groups contained in one molecule by the molecular weight of the additive, It is preferable that it is 0.01 or more.
These characteristics are that the humidity dependency improver is bonded (hydrogen bond) to the hydrogen bond position of the cellulose acylate resin, so that the orientation of water molecules in the cellulose acylate resin and the cellulose acylate by desorption of the water molecules. It is presumed to act to cancel the retardation change caused by the change in the charge distribution of the rate.

  Specific examples of the humidity dependency improver include, but are not limited to, the following compounds (A-1) to (A-17).

Furthermore, the molecular weight of the humidity dependency improving agent is preferably 130 or more and 500 or less. When the molecular weight is less than 130, the volatility becomes insufficient, and when it is 500 or more, the solubility in a solvent and the compatibility with the cellulose acylate resin deteriorate.
Specific examples of the humidity dependency improving agent that satisfies such conditions include the following compounds (A-18) to (A-42), but are not limited thereto.

<Application to optical compensation film>
Next, an optical compensation film for realizing this optical compensation will be specifically described.
The optical compensation film of the present invention contributes to the expansion of the viewing angle contrast and the reduction of color shift depending on the viewing angle of liquid crystal display devices, particularly OCB mode and VA mode liquid crystal display devices.
The optical compensation film of the present invention may be disposed between the polarizing plate on the observer side and the liquid crystal cell, or may be disposed between the polarizing plate on the back side and the liquid crystal cell, or may be disposed on both sides. Also good.
For example, it can be incorporated into the liquid crystal display device as an independent member, or a protective film that protects the polarizing film is provided with optical characteristics to function as a transparent film, so that the liquid crystal can be used as one member of a polarizing plate. It can also be incorporated inside the display device.
The optical compensation film of the present invention can also have at least two layers of a transparent support and an optically anisotropic layer having other optical properties.

[Optically anisotropic layer (hybrid orientation anisotropic layer)]
The optical compensation film of the present invention has at least one optically anisotropic layer formed from a liquid crystalline compound according to a target liquid crystal system. The optically anisotropic layer may be formed directly on the surface of the optical compensation film, or may be formed on the alignment film by forming an alignment film on the optical compensation film.
Also, an optical compensation film having an optically anisotropic layer can be produced by transferring a liquid crystalline compound layer formed on another substrate onto the optical compensation film using an adhesive, an adhesive, or the like. Is possible.

  Examples of the liquid crystalline compound used for forming the optically anisotropic layer include a rod-like liquid crystalline compound and a discotic liquid crystalline compound (hereinafter, the discotic liquid crystalline compound may be referred to as a “discotic liquid crystalline compound”). . The rod-like liquid crystal compound and the discotic liquid crystal compound may be a high-molecular liquid crystal or a low-molecular liquid crystal. In addition, the compound finally contained in the optically anisotropic layer no longer needs to exhibit liquid crystallinity. For example, when a low-molecular liquid crystalline compound is used for the production of the optically anisotropic layer, In the process of forming the isotropic layer, the compound may be cross-linked and no longer exhibits liquid crystallinity.

[Bar-shaped liquid crystalline compound]
Examples of the rod-like liquid crystalline compound that can be used in the optically anisotropic layer of the present invention include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexane. , Cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines, phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used.
The rod-like liquid crystalline compound includes a metal complex. A liquid crystal polymer containing a rod-like liquid crystal compound in a repeating unit can also be used. In other words, the rod-like liquid crystalline compound may be bonded to a (liquid crystal) polymer.
For rod-like liquid crystalline compounds, Chapter 4, Chapter 7 and Chapter 11 of Quarterly Chemical Review Vol. 22, “Liquid Crystal Chemistry” (1994, edited by the Chemical Society of Japan), and Liquid Crystal Device Handbook (Japan Society for the Promotion of Science) 142 chapter)).

The birefringence of the rod-like liquid crystalline compound used in the present invention is preferably in the range of 0.001 to 0.7.
The rod-like liquid crystalline compound preferably has a polymerizable group in order to fix the alignment state. The polymerizable group is preferably an unsaturated polymerizable group or an epoxy group, more preferably an unsaturated polymerizable group, and still more preferably an ethylenically unsaturated polymerizable group.

[Discotic liquid crystalline compounds]
Examples of discotic liquid crystalline compounds include C.I. Destrade et al., Mol. Cryst. 71, 111 (1981), benzene derivatives described in C.I. Destrade et al., Mol. Cryst. 122, 141 (1985), Physics lett, A, 78, 82 (1990); Kohne et al., Angew. Chem. 96, 70 (1984) and the cyclohexane derivatives described in J. Am. M.M. Lehn et al. Chem. Commun. , 1794 (1985), J. Am. Zhang et al., J. Am. Chem. Soc. 116, 2655 (1994), azacrown type and phenylacetylene type macrocycles are included.

  The discotic liquid crystalline compound exhibits liquid crystallinity with a structure in which a linear alkyl group, an alkoxy group or a substituted benzoyloxy group is radially substituted as a side chain of the mother nucleus with respect to the mother nucleus at the center of the molecule. Also included are compounds. The molecule or the assembly of molecules is preferably a compound having rotational symmetry and imparting a certain orientation.

  As described above, when an optically anisotropic layer is formed from a liquid crystalline compound, the compound finally contained in the optically anisotropic layer no longer needs to exhibit liquid crystallinity. For example, a low-molecular discotic liquid crystalline compound has a group that reacts with heat or light, and the group reacts with heat or light to polymerize or crosslink to increase the molecular weight. When a layer is formed, the compound contained in the optically anisotropic layer may no longer have liquid crystallinity. Preferred examples of the discotic liquid crystalline compound are described in JP-A-8-50206. Moreover, about superposition | polymerization of a discotic liquid crystalline compound, Unexamined-Japanese-Patent No. 8-27284 has description.

  In order to fix the discotic liquid crystalline compound by polymerization, it is necessary to bond a polymerizable group as a substituent to the discotic core of the discotic liquid crystalline compound. However, when the polymerizable group is directly connected to the disc-shaped core, it becomes difficult to maintain the orientation state in the polymerization reaction. Therefore, it is preferable to introduce a linking group between the discotic core and the polymerizable group.

  In the present invention, in the optically anisotropic layer, the rod-like compound or the molecule of the discotic compound is fixed in an oriented state. The orientation average direction of the molecular symmetry axis of the liquid crystalline compound at the interface on the optical compensation film side has an intersection angle of about 45 ° with the slow axis in the plane of the optical compensation film. In the present specification, “approximately 45 °” means an angle in a range of 45 ° ± 5 °, preferably 42 to 48 °, and more preferably 43 to 47 °.

The orientation average direction of the molecular symmetry axis of the liquid crystal compound can be generally adjusted by selecting a material of the liquid crystal compound or the alignment film or by selecting a rubbing treatment method.
In the present invention, for example, in the case of producing an optical compensation film for the OCB method, an alignment film for forming an optically anisotropic layer is produced by rubbing treatment and rubbed in a direction of 45 ° with respect to the slow axis of the optical compensation film. By processing, an optically anisotropic layer in which the orientation average direction of the molecular symmetry axis of the liquid crystalline compound at least at the cellulose acylate film interface is 45 ° with respect to the slow axis of the cellulose acylate film is formed. Can do.
For example, the optical compensation film of the present invention can be continuously produced by using the long optical compensation film of the present invention whose slow axis is perpendicular to the longitudinal direction.

  The plasticizer, surfactant and polymerizable monomer used together with the liquid crystal compound are compatible with the discotic liquid crystal compound and may change the tilt angle of the liquid crystal compound or do not inhibit the alignment. preferable. A polymerizable monomer (eg, a compound having a vinyl group, a vinyloxy group, an acryloyl group and a methacryloyl group) is preferred. The amount of the compound added is generally in the range of 1 to 50% by mass and preferably in the range of 5 to 30% by mass with respect to the liquid crystal compound. In addition, when a monomer having 4 or more polymerizable reactive functional groups is mixed and used, adhesion between the alignment film and the optically anisotropic layer can be improved.

When a discotic liquid crystalline compound is used as the liquid crystalline compound, it is preferable to use a polymer that has a certain degree of compatibility with the discotic liquid crystalline compound and can change the tilt angle of the discotic liquid crystalline compound.
A cellulose ester can be mentioned as an example of a polymer. The addition amount of the polymer is preferably in the range of 0.1 to 10% by mass with respect to the discotic liquid crystalline compound so as not to inhibit the orientation of the discotic liquid crystalline compound. %, More preferably in the range of 0.1 to 5% by weight.
The discotic nematic liquid crystal phase-solid phase transition temperature of the discotic liquid crystalline compound is preferably 70 to 300 ° C, and more preferably 70 to 170 ° C.

  In the present invention, the “other” optically anisotropic layer described above has at least in-plane optical anisotropy. The in-plane retardation Re of the optically anisotropic layer is preferably 3 to 300 nm, more preferably 5 to 200 nm, and still more preferably 10 to 100 nm. The retardation Rth in the thickness direction of the optically anisotropic layer is preferably 20 to 400 nm, and more preferably 50 to 200 nm. The thickness of the optically anisotropic layer is preferably 0.1 to 20 μm, more preferably 0.5 to 15 μm, and still more preferably 1 to 10 μm.

[Alignment film]
The optical compensation film of the present invention may have an alignment film between the support and the optically anisotropic layer. In addition, the alignment film is used only when the optically anisotropic layer is prepared, and after forming the optically anisotropic layer on the alignment film, only the optically anisotropic layer is used as the optical compensation film (support) of the present invention. ) May be transferred onto.
In the present invention, the alignment film is preferably a layer made of a crosslinked polymer. The polymer used for the alignment film may be either a polymer that can be crosslinked by itself or a polymer that is crosslinked by a crosslinking agent. The alignment film is formed by reacting a polymer having a functional group or a polymer having a functional group introduced therein with light, heat, pH change, or the like; or a cross-linking agent that is a highly reactive compound Can be formed by introducing a linking group derived from a cross-linking agent between polymers to cross-link between the polymers.

The alignment film composed of a crosslinked polymer can be usually formed by applying a coating solution containing the polymer or a mixture of a polymer and a crosslinking agent on a support, followed by heating.
In the rubbing process described later, it is preferable to increase the degree of cross-linking in order to suppress dust generation in the alignment film. A value (1- (Ma / Mb)) obtained by subtracting 1 from the ratio (Ma / Mb) of the amount (Ma) of the crosslinking agent remaining after crosslinking to the amount (Mb) of the crosslinking agent added to the coating solution. When Mb)) is defined as the degree of crosslinking, the degree of crosslinking is preferably 50 to 100%, more preferably 65 to 100%, still more preferably 75 to 100%.

(Polarizer)
The polarizing plate of the present invention is composed of a polarizing film and a pair of polarizing plate protective films sandwiching the polarizing film, and such a constitution is preferable from the viewpoints of polarizing ability and transmittance. The above-mentioned optical compensation film is included in at least one of the polarizing plate protective films of the pair of polarizing plate protective films. As a method for producing the polarizing plate, for example, after cutting into a desired shape such as a rectangular shape, the optical compensation film may be bonded to a polarizing film, or after being bonded to a long polarizing film. It can also be cut into a desired shape.
The polarizing plate of the present invention has not only a polarizing function but also an excellent optical compensation function, and can be easily incorporated into a liquid crystal display device. Moreover, the aspect which used the said optical compensation film as the protective film of a polarizing film contributes also to thickness reduction of a liquid crystal display device.

<Coating layer>
As for the protective film for polarizing plates of this invention, especially the protective film arrange | positioned at the visual recognition side of a polarizing film, it is preferable that the coating layer (barrier layer) is formed on the transparent base film. The preferred range of the thickness of the coating layer varies depending on the type of the coating layer. It is preferable to set the coating layer to an optimum thickness because it has excellent low moisture permeability and does not cause adverse effects such as increased curl. If the curl becomes too large, it will hinder subsequent processes for producing a polarizing plate, for example, a bonding process with a polarizing film and handling. Further, it is not preferable that the curl remains not only in the manufacturing process but also as the polarizing plate, which causes display unevenness in the LCD. Therefore, it is preferable to control the film thickness of the coating layer to an optimum range in order to reduce the curl to such an extent that it does not occur or is practically unproblematic. On the other hand, a preferable range of the lower limit of the film thickness is determined based on moisture permeability. The coating layer consists of at least one layer, and two or more layers are also possible. It is particularly preferable to use two or more different coating layers at the same time from the viewpoint of reducing moisture permeability.

<< moisture permeability >>
Next, the moisture permeability will be described in detail.
The measurement method of moisture permeability is “Polymer Physical Properties II” (Polymer Experiment Course 4, Kyoritsu Shuppan), pages 285-294: Measurement of vapor permeation amount (mass method, thermometer method, vapor pressure method, adsorption amount method) The film sample of 70 mmφ according to the present invention was conditioned at 60 ° C. and 95% RH for 24 hours, respectively, and from the mass difference before and after the humidity adjustment, according to JIS Z-0208, per unit area Was calculated (g / m ² ). At this time, the operation of taking out and weighing the cup placed in the thermo-hygrostat at an appropriate time interval is repeated, and the mass increase per unit time is obtained for each of two consecutive weighings, and it is constant within 5%. Evaluation continued until. Moreover, in order to exclude the influence by the moisture absorption etc. of a sample, the blank cup which does not put a hygroscopic agent was measured, and the value of moisture permeability was correct | amended.
In addition, the value of moisture permeability used in the present invention is the value when measuring a protective film having a coating layer in which a layered inorganic compound is dispersed in a polyvinyl alcohol, an ethylene vinyl alcohol copolymer, and a resin layer thereof. The value of moisture permeability from was used. The moisture permeability of a commercially available cellulose acetate film measured by the above measurement method is generally 80 μm in thickness and 1,400 to 1,500 g / m ² · day under the above conditions. The upper limit of moisture permeability of the polarizing plate protective film of the present invention is preferably 300 g / m ² · day or less, and more preferably 200 g / m ² · day or less. If the moisture permeability is higher than the above upper limit value, the effect of reducing the occurrence of unevenness in the display image due to the change in the size of the polarizing film due to the change in temperature and humidity during low-term use is low. The lower limit is not particularly limited, but is preferably 20 g / m ² · day or more, more preferably 30 g / m ² · day or more from the viewpoint of productivity during polarizing plate processing. Within this range, the performance (polarization degree, single plate transmittance) as a polarizing plate is not deteriorated, and unevenness of the display image is caused by changes in the size of the polarizing film due to changes in temperature and humidity during long-term use. Can be prevented from occurring.

  Further, by using the protective film in the configuration of the present invention, it is possible to remarkably reduce a change in display performance (viewing angle contrast / tone viewing angle dependency) of the liquid crystal display device depending on the use environment. As described above, when the cellulose acylate film is hydrated, the retardation changes due to the orientation of water molecules in the cellulose acylate resin and the change in the charge distribution of the cellulose acylate due to the desorption of water molecules. As a result, the liquid crystal display device changes in contrast and color, particularly in an oblique direction, according to environmental humidity. By using a protective film with a barrier layer as a polarizer protective film, the penetration of water molecules into the cellulose acylate placed on the opposite side via the polarizer is delayed and deterred. It is considered that the change in the optical characteristics of cellulose acylate is suppressed, and as a result, the humidity dependency of the display characteristics of the liquid crystal display device is reduced.

  The cured coating layer may be composed of a single layer or a plurality of layers, but is preferably a single layer that is simple in the production process. The single layer in this case refers to a coating layer formed of the same composition, and may be formed by a plurality of coatings as long as the composition after coating and drying has the same composition. On the other hand, the term “multiple layers” refers to the formation of a plurality of compositions having different compositions.

<< Adhesive >>
The adhesive between the polarizing film and the protective film is not particularly limited, and examples thereof include PVA resins (including modified PVA such as acetoacetyl group, sulfonic acid group, carboxyl group, oxyalkylene group) and boron compound aqueous solution. PVA resin is preferable. The thickness of the adhesive layer is preferably 0.01 to 10 μm, particularly preferably 0.05 to 5 μm after drying.

<< Integrated manufacturing process of polarizing film and transparent protective film >>
The polarizing plate that can be used in the present invention has a drying step in which the polarizing film is stretched and then contracted to reduce the volatile content rate, but after drying or after the transparent protective film is bonded to at least one side during drying, It is preferable to have a post-heating step.
In an embodiment in which the transparent protective film also serves as a support for the optically anisotropic layer functioning as a transparent film, a transparent support having a transparent protective film on one side and an optically anisotropic layer on the other side is pasted. After combining, it is preferable to post-heat.

<Performance of polarizing plate>
The optical properties and durability (short-term, long-term storage stability) of a transparent protective film, a polarizer (polarizing film), and a transparent support, which are related to the present invention, are commercially available super high contrast products (for example, It is preferable to have equivalent or better performance.
Specifically, the visible light transmittance is 42.5% or more, and the degree of polarization {(Tp−Tc) / (Tp + Tc)} ^1/2 ≧ 0.9995 (where Tp is parallel transmittance and Tc is orthogonal transmission) The rate of change in light transmittance before and after leaving in an atmosphere of 60 ° C. and humidity 90% RH for 500 hours and 80 ° C. in a dry atmosphere for 3 hours or less is 3% or less based on the absolute value. Is preferable, and 1% or less is more preferable. The rate of change in the degree of polarization is preferably 1% or less, more preferably 0.1% or less, based on the absolute value.

(Liquid crystal display device)
The polarizing plate obtained by laminating the optical compensation film or the optical compensation film and the polarizing film is advantageously used for a liquid crystal display device, particularly a transmissive liquid crystal display device. The transmissive liquid crystal display device includes a liquid crystal cell and two polarizing plates arranged on both sides thereof.
The polarizing plate includes a polarizing film and at least two transparent protective films disposed on both sides of the polarizing film. Further, the liquid crystal cell carries a liquid crystal between two electrode substrates.
One optical compensation film of the present invention is disposed between the liquid crystal cell and one of the polarizing plates, or two optical compensation films are disposed between the liquid crystal cell and both polarizing plates.
The polarizing plate of the present invention may be used as at least one of the two polarizing plates disposed on both sides of the liquid crystal cell. In this case, the polarizing plate of the present invention is arranged so that the optical compensation film is on the liquid crystal cell side.
The liquid crystal cell is preferably in VA mode, OCB mode, IPS mode, or TN mode.

<VA mode>
In a VA mode liquid crystal cell, rod-like liquid crystal molecules are aligned substantially vertically when no voltage is applied.
The VA mode liquid crystal cell includes (1) a narrowly defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied (Japanese Patent Laid-Open No. Hei 2-). (2) Liquid crystal cell (SID97, Digest of tech. Papers (Proceedings) 28 (1997) 845 in which the VA mode is converted into a multi-domain (MVA mode) in order to enlarge the viewing angle. (3) A liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied (Preliminary Collection 58- 59 (1998)), and (4) SURVAVAL mode liquid crystal cells (announced at LCD International 98).

<OCB mode>
The OCB mode liquid crystal cell is a bend alignment mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned in a substantially opposite direction (symmetrically) between an upper portion and a lower portion of the liquid crystal cell.
A liquid crystal display device using a bend alignment mode liquid crystal cell is disclosed in US Pat. Nos. 4,583,825 and 5,410,422. Since the rod-like liquid crystal molecules are symmetrically aligned at the upper and lower portions of the liquid crystal cell, the bend alignment mode liquid crystal cell has a self-optical compensation function.
For this reason, this liquid crystal mode is also called an OCB (Optically Compensatory Bend) liquid crystal mode. The bend alignment mode liquid crystal display device has an advantage of high response speed.

<IPS mode>
In an IPS mode liquid crystal cell, rod-like liquid crystal molecules are aligned substantially parallel to the substrate, and the liquid crystal molecules respond in a planar manner when an electric field parallel to the substrate surface is applied. In the IPS mode, black is displayed when no electric field is applied, and the transmission axes of the pair of upper and lower polarizing plates are orthogonal. A method of reducing leakage light at the time of black display in an oblique direction and improving a viewing angle using an optical compensation film is disclosed in JP-A-10-54982, JP-A-11-202323, and JP-A-9-292522. No. 11-133408, No. 11-305217, No. 10-307291, and the like.

<TN mode>
In a TN mode liquid crystal cell, rod-like liquid crystal molecules are substantially horizontally aligned when no voltage is applied, and are twisted and aligned at 60 to 120 °.
The TN mode liquid crystal cell is most frequently used as a color TFT liquid crystal display device, and is described in many documents.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples.

(Example 1)
<Production of optical compensation film>
<< Preparation of transparent support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose triacetate (triacetyl cellulose: TAC) solution.
Table 3 shows the maximum absorption wavelength λ _max measured for the compound of the following structural formula (A).

[Material / solvent composition]
・ Cellulose acetate (degree of substitution 2.81, degree of acetylation 60.2%) ... 100 parts by mass-Triphenyl phosphate (plasticizer) ... 6.5 Parts by mass, biphenyldiphenyl phosphate (plasticizer), 5.2 parts by mass, methylene chloride (first solvent), ...... -633 parts by mass-Methanol (second solvent) ... 95 parts by mass
-Rth raising agent shown in the following structural formula (A) ... 3 parts by mass

  The obtained solution (dope) was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 140% under a temperature condition of 190 ° C. to produce a transparent support. In addition, Tg of the used cellulose acylate film is 148 degreeC. The thickness of the produced transparent support was 90 μm.

<Measurement of Re and Rth>
As the optical characteristics after conditioning the prepared transparent support in an environment of 25 ° C. and 55% RH for 2 hours, Re and Rth of the support at wavelengths of 450 nm, 550 nm, and 630 nm were described above. According to the method, it measured with KOBRA 21ADH (made by Oji Scientific Instruments). The measurement results are shown in Table 2.

<Measurement of humidity dependency of Re and Rth (ΔRe, ΔRth)>
As the optical characteristics after the prepared transparent support was conditioned for 2 hours in an environment of 25 ° C., 10% RH, and 25 ° C., 80% RH, Re and Rth of the support at a wavelength of 550 nm Was measured with KOBRA 21ADH (manufactured by Oji Scientific Instruments). Based on the measurement results, ΔRe = Re (25 ° C., 10% RH) −Re (25 ° C., 80% RH) and ΔRth = Rth (25 ° C., 10% RH) −Rth (25 ° C., 80% RH) The values calculated as) are shown in Table 3.

<Measurement of orientation degree P>
The degree of orientation of the produced transparent support was measured. Specifically, a single crystal X-ray diffractometer (RAPID R-AXIS manufactured by Rigaku Denki Kogyo Co., Ltd.) used CuKα rays as an X-ray source and generated X-rays at 40 kV-36 mA. The collimator was 0.8 mmφ, and the support was fixed using a transmission sample stage. The exposure time was 600 seconds. Table 3 shows the degree of orientation measured using this single crystal X-ray diffractometer.

<Saponification treatment>
A 1.0 N potassium hydroxide solution (solvent: water / isopropyl alcohol / propylene glycol = 69.2 parts by mass / 15 parts by mass / 15.8 parts by mass) is applied to the band surface side of the produced transparent support at 10 mL / m. ^{2 was} applied and kept at a temperature of about 40 ° C. for 30 seconds, and then the alkaline liquid was scraped off, washed with pure water, and water droplets were removed with an air knife. Then, it dried at 100 degreeC for 15 second. The contact angle with respect to pure water of the treated surface of this support was determined to be 42 °.

<< Preparation of alignment film >>
On this support, an alignment film coating solution having the following composition was coated at 28 mL / m ² with a # 16 wire bar coater. The film was dried with warm air of 60 ° C. for 60 seconds and further with warm air of 90 ° C. for 150 seconds to produce an alignment film.

[Alignment film coating solution composition]
・ Modified polyvinyl alcohol shown in the following structural formula (B): 10 parts by mass, water: ... 371 parts by mass, methanol ... 119 parts by mass, glutaraldehyde (crosslinking agent) ... 0.5 parts by mass
・ Citrate ester (AS3 manufactured by Sankyo Chemical Co., Ltd.) ... 0.35 parts by mass

  Drying was performed at 25 ° C. for 60 seconds, 60 ° C. warm air for 60 seconds, and 90 ° C. warm air for 150 seconds. The thickness of the alignment film after drying was 1.1 μm. Further, the surface roughness of the alignment film was measured with an atomic force microscope (AFM: Atomic Force Microscope, SPI3800N, manufactured by Seiko Instruments Inc.), and found to be 1.147 nm.

<< Formation of optically anisotropic layer >>
In 400.0 parts by mass of methyl ethyl ketone, 100 parts by mass of a discotic liquid crystal compound represented by the following structural formula (C), 0.4 parts by mass of an air interface alignment controller represented by the following structural formula (D), a photopolymerization initiator ( A coating solution was prepared by dissolving 3 parts by mass of Irgacure 907 (manufactured by Ciba Geigy) and 1 part by mass of a sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.).
This coating solution was applied onto the alignment film with a # 2.0 wire bar. This was attached to a metal frame and heated in a constant temperature bath at 120 ° C. for 90 seconds to align the discotic liquid crystal compound.
Next, using a 120 W / cm high-pressure mercury lamp at 80 ° C., ultraviolet rays were irradiated for 1 minute to polymerize the discotic liquid crystal compound. Then, it stood to cool to room temperature. In this way, an optically anisotropic layer was formed on the support via an alignment film to produce an optical compensation film.

<< Measurement of optical properties of optically anisotropic layer >>
An alignment film was produced on glass by the same method as described above, the optical anisotropic layer was formed on the alignment film, and Re ₍₅₅₀₎ was measured with light having a wavelength of 550 nm using KOBRA 21ADH. there were.
In addition, when the retardation ratio was measured using KOBRA 21ADH with light having wavelengths of 450 nm and 650 nm, Re ₍₄₅₀₎ / Re ₍₆₅₀₎ was 1.15. Moreover, it was 0.8 micrometer when the thickness of the optically anisotropic layer was measured.

The discotic liquid crystal compound represented by the structural formula (C) was injected while heating into a 2 μm glass cell in which a director of the discotic liquid crystal compound was aligned in parallel in the plane, and left for 2 minutes.
When the retardation value Re_m (550) of this cell was measured using KOBRA 21ADH with light having a wavelength of 550 nm, it was 235 nm. Since the cell gap was 2 μm, the value of Re_m (550) / d was 0.118.

(Example 2)
<Production of optical compensation film>
<< Preparation of transparent support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose triacetate (triacetyl cellulose: TAC) solution.

[Material / solvent composition]
・ Cellulose acetate (degree of substitution 2.87, acetylation degree 60.9%) ・ ・ ・ ・ 100 parts by mass ・ Triphenyl phosphate (plasticizer) ・ ・ ・ ・ ・ ・ 6.5 Parts by mass, biphenyldiphenyl phosphate (plasticizer), 5.2 parts by mass, methylene chloride (first solvent), ...... -630 parts by mass-Methanol (second solvent) ... 95 parts by mass
-Rth raising agent shown in the structural formula (A) ... 2.5 parts by mass

  The obtained dope was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 150% under a temperature condition of 185 ° C. to prepare a transparent support. In addition, Tg of the used cellulose acylate film is 149 degreeC. The thickness of the produced transparent support was 85 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Example 3)
<Production of optical compensation film>
<< Preparation of transparent support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose triacetate (triacetyl cellulose: TAC) solution.

[Material / solvent composition]
・ Cellulose acetate (degree of substitution 2.81, degree of acetylation 60.2%) ... 100 parts by mass-Triphenyl phosphate (plasticizer) ... 6.5 Parts by mass, biphenyldiphenyl phosphate (plasticizer), 5.2 parts by mass, methylene chloride (first solvent), ......・ 639 parts by mass ・ Methanol (second solvent) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 96 parts by mass
-Rth raising agent shown in the above structural formula (A) ... 4.0 parts by mass

  The obtained dope was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, the film was uniaxially stretched to 140% under a temperature condition of 200 ° C. to produce a transparent support, which was used as an optical compensation film. In addition, Tg of the used cellulose acylate film is 149 degreeC. The thickness of the produced transparent support (optical compensation film) was 95 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

Example 4
<Production of optical compensation film>
<< Preparation of transparent support >>
A dope prepared with the same composition as in Example 1 was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 110% under a temperature condition of 180 ° C. to produce a transparent support. In addition, Tg of the used cellulose acylate film is 148 degreeC. The produced transparent support had a thickness of 90 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Example 5)
<Production of optical compensation film>
<< Preparation of transparent support >>
A dope prepared with the same composition as in Example 1 was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 160% under a temperature condition of 190 ° C. to produce a transparent support. In addition, Tg of the used cellulose acylate film is 148 degreeC. The produced transparent support had a thickness of 95 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Example 6)
<Production of optical compensation film>
<< Preparation of support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose triacetate (triacetyl cellulose: TAC) solution.

[Material / solvent composition]
・ Cellulose acetate (degree of substitution 2.81, degree of acetylation 60.2%) ... 100 parts by mass-Triphenyl phosphate (plasticizer) ... 6.5 Parts by mass, biphenyldiphenyl phosphate (plasticizer), 5.2 parts by mass, methylene chloride (first solvent), ...... -633 parts by mass-Methanol (second solvent) ... 95 parts by mass
-Rth raising agent shown in the structural formula (A)-3 parts by mass

  The obtained dope was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 100 ° C. drying air for 10 minutes and 140 ° C. drying air for 20 minutes to produce a film. The average drying rate at a solvent volatile content of 20% in the film at this time was 1.1% by mass / min. Thereafter, this film was uniaxially stretched to 140% under a temperature condition of 190 ° C. to produce a transparent support. In addition, Tg of the used cellulose acylate film is 148 degreeC. The produced transparent support had a thickness of 90 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Example 7)
<Production of optical compensation film>
<< Preparation of support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a CAP (cellulose acetate propionate) solution.

[Material / solvent composition]
・ Cellulose acetate propionate 100 parts by mass (acetyl substitution degree 2.81, propionyl substitution degree 0.68, total substitution degree 2.57, acetylation degree 57 .1%)
・ Compound shown in the following structural formula (E) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 5 parts by mass ・ Compound shown in the following structural formula (F) ・ ・ ・ ・ ・ ・..... 5 parts by mass. Methylene chloride (first solvent) ..... 392 parts by mass. Methanol (second solvent). ) ... 54 parts by mass
-Rth raising agent shown in the above structural formula (A) ... 2 parts by mass

  The obtained dope was cast on a glass plate, dried at room temperature for 1 minute, and then dried at 70 ° C. for 6 minutes. The obtained cellulose propionate film was peeled from the glass plate and dried at 140 ° C. for 30 minutes. The dried film was uniaxially stretched to 130% at a temperature of 130 ° C. to prepare a support. The film thickness of the produced film was 80 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Example 8)
<Production of optical compensation film>
<< Preparation of support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose triacetate (triacetyl cellulose: TAC) solution.

[Material / solvent composition]
-Cellulose acetate (substitution degree 2.81, acetylation degree 60.2%) ... 100 parts by mass-m-hydroxybenzoic acid ... · · 10 parts by mass · Methylene chloride (first solvent) · · · · · · 614 parts by mass · Methanol (second solvent) · · · ... 92 parts by mass
-Rth raising agent shown in the structural formula (A)-3 parts by mass

  The obtained solution (dope) was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 140% under a temperature condition of 190 ° C. to produce a transparent support. In addition, Tg of the used cellulose acylate film is 146 degreeC. The thickness of the produced transparent support was 80 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

Example 9
<Production of optical compensation film>
An optical compensation film was produced by the same production method as in Example 1.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Example 10)
<Production of optical compensation film>
A solution (dope) produced under the same conditions as in Example 8 was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 140% under a temperature condition of 200 ° C. to produce a transparent support. In addition, Tg of the used cellulose acylate film is 146 degreeC. The thickness of the produced transparent support was 80 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Example 11)
<Production of optical compensation film>
An optical compensation film was produced by the same production method as in Example 10.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

Example 12
<Production of optical compensation film>
An optical compensation film was produced by the same production method as in Example 4.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Comparative Example 1)
<Production of optical compensation film>
<< Preparation of transparent support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose triacetate (triacetyl cellulose: TAC) solution.

[Material / solvent composition]
・ Cellulose acetate (degree of substitution 2.81, degree of acetylation 60.2%) ... 100 parts by mass-Triphenyl phosphate (plasticizer) ... 6.5 Parts by mass, biphenyldiphenyl phosphate (plasticizer), 5.2 parts by mass, methylene chloride (first solvent), ......・ 617 parts by mass
-Methanol (second solvent) ... 93 parts by mass

  The obtained dope was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 140% under a temperature condition of 190 ° C. to produce a transparent support. In addition, Tg of the used cellulose acylate film is 148 degreeC. The thickness of the produced transparent support was 90 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Comparative Example 2)
<Production of optical compensation film>
<< Preparation of transparent support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose triacetate (triacetyl cellulose: TAC) solution.

[Material / solvent composition]
・ Cellulose acetate (degree of substitution 2.81, degree of acetylation 60.2%) ... 100 parts by mass-Triphenyl phosphate (plasticizer) ... 6.5 Parts by mass, biphenyldiphenyl phosphate (plasticizer), 5.2 parts by mass, methylene chloride (first solvent), ...... -617 parts by mass-Methanol (second solvent) ... 93 parts by mass
-Rth raising agent shown in the structural formula (A) ... 2.5 parts by mass

  The obtained dope was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 120% under a temperature condition of 150 ° C. to produce a transparent support. In addition, Tg of the used cellulose acylate film is 148 degreeC. The thickness of the produced transparent support was 90 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Comparative Example 3)
<Production of optical compensation film>
<< Preparation of transparent support >>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose triacetate (triacetyl cellulose: TAC) solution.
Table 3 shows the maximum absorption wavelength λ _max measured for the compound of the following structural formula (E).

[Material / solvent composition]
・ Cellulose acetate (degree of substitution 2.81, degree of acetylation 60.2%) ... 100 parts by mass-Triphenyl phosphate (plasticizer) ... 6.5 Parts by mass, biphenyldiphenyl phosphate (plasticizer), 5.2 parts by mass, methylene chloride (first solvent), ...... -617 parts by mass-Methanol (second solvent) ... 93 parts by mass
・ Compound represented by the following structural formula (G): 10 parts by mass

  The obtained dope was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, this film was uniaxially stretched to 120% under a temperature condition of 185 ° C. to prepare a transparent support. In addition, Tg of the used cellulose acylate film is 148 degreeC. The thickness of the produced transparent support was 80 μm.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Comparative Example 4)
<Production of optical compensation film>
<< Preparation of transparent support >>
A dope prepared with the same composition as in Example 1 was cast using a casting machine having a band having a width of 2 m and a length of 65 m. After the film surface temperature on the band reached 40 ° C., the film was dried for 1 minute, peeled off, and further dried with 140 ° C. drying air for 30 minutes to produce a film. At this time, the average drying rate at a solvent volatile content of 20% in the film was 1.5% by mass / min. Thereafter, the film was uniaxially stretched to 200% under a temperature condition of 190 ° C., but the film was broken. When the degree of orientation of the fractured transparent support was measured in the same manner as in Example 1, it was 0.31. Therefore, a transparent support having an orientation degree P exceeding 0.30 could not be produced.

(Comparative Example 5)
<Production of optical compensation film>
<< Preparation of transparent support >>
A transparent support was produced in the same manner as in Comparative Example 1, and this was used as an optical compensation film.

  About the produced transparent support body, Re and Rth, humidity dependence, and orientation degree P were measured. The results are shown in Tables 2 and 3.

<Formation of optically anisotropic layer>
In the same manner as in Example 1, the support was subjected to saponification treatment, an alignment film was formed, and an optically anisotropic layer was formed on the alignment film to prepare an optical compensation film.

(Preparation of polarizing plate)
First, iodine was adsorbed on a stretched polyvinyl alcohol film to prepare a polarizing film.
Then, each optical compensation film of Examples 1-8, 11, Comparative Examples 1-3, and Comparative Example 5 was attached to one surface of the polarizing film using a polyvinyl alcohol-based adhesive, and the polarized light A commercially available cellulose triacetate film (Fujitac TD80UF, manufactured by Fuji Film Co., Ltd.) that had been saponified using a polyvinyl alcohol-based adhesive was attached to the other surface of the membrane. Note that when the optical compensation film was attached to one surface of the polarizing film, the transmission axis of the polarizing film and the slow axis of the optical compensation film were arranged in parallel. Thus, 10 types of polarizing plates based on Examples 1-8, 11, Comparative Examples 1-3, and Comparative Example 5 were produced.

<Preparation of protective film for polarizing plate with coating layer>
<< Preparation of coating solution for coating layer >>
As shown in the composition below, the layered inorganic compound was mixed with water so as to have a desired concentration, and then subjected to high-pressure dispersion treatment at 30 Mpa three times using a high-pressure disperser, and dispersed in water.

[Composition of coating solution for coating layer]
-HR3010 (manufactured by Kuraray Co., Ltd.) ... 5 parts by mass-Underwater high pressure dispersant ME-100 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 40 parts by mass (solid content ratio: 5% by weight) (manufactured by Coop Chemical Co., Ltd.)
・ Water ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 75 parts by mass

<Coating layer coating>
In the triacetyl cellulose (TAC-TD80U, manufactured by FUJIFILM Corporation), the side on which the coating layer was provided was saponified at 50 ° C. with a 1 mol / L alkaline solution.
Thereafter, the coating solution for coating layer was applied on the saponified surface of the triacetylcellulose film so that the film thickness after drying was 20 μm using a coater having a throttle die.
Then, it apply | coated on conditions with a conveyance speed of 30 m / min, dried at 130 degreeC for 5 minute (s), and wound up.

<Measurement of moisture permeability>
The measurement method of moisture permeability is “Polymer Physical Properties II” (Polymer Experiment Course 4, Kyoritsu Shuppan), pages 285-294: Measurement of vapor permeation amount (mass method, thermometer method, vapor pressure method, adsorption amount method) The film sample 70 mmφ used in the present invention was conditioned at 60 ° C. and 95% RH for 24 hours, respectively, and according to JIS Z-0208, moisture permeability = mass after humidity adjustment−humidity control The amount of water per unit area (g / m ² ) was calculated based on the previous mass. At this time, the operation of taking out and weighing the cup placed in the thermo-hygrostat at an appropriate time interval is repeated, and the mass increase per unit time is obtained for each of two consecutive weighings, and it is constant within 5%. Evaluation continued until. Moreover, in order to exclude the influence by the moisture absorption etc. of a sample, the blank cup which does not put a hygroscopic agent was measured, and the value of moisture permeability was correct | amended.

The moisture permeability of the coating layer was coated triacetyl cellulose was significantly reduced relative moisture permeability 1,400 g / m ² of triacetylcellulose not coated 230 g / m ^2, and the coating layer.

(Preparation of polarizing plate with coating layer)
A polarizing film was prepared by adsorbing iodine to a stretched polyvinyl alcohol film.
Thereafter, the optical compensation films of Examples 9, 10, and 12 were attached to one surface of the polarizing film using a polyvinyl alcohol-based adhesive, and the other surface of the polarizing film was polyvinyl alcohol-based. Triacetylcellulose coated with the above saponified coating layer was attached using an adhesive. Note that when the optical compensation film was attached to one surface of the polarizing film, the transmission axis of the polarizing film and the slow axis of the optical compensation film were arranged in parallel. In this manner, polarizing plates of Examples 9, 10, and 12 were produced.

<Mounting evaluation with liquid crystal display devices>
<< Preparation of bend alignment liquid crystal cell >>
A polyimide film was provided as an alignment film on a glass substrate with an ITO electrode, and the alignment film was rubbed. The obtained two glass substrates were faced to each other so that the rubbing directions were parallel to each other, and the cell gap was set to 4.7 μm. A bend-aligned liquid crystal cell was prepared by injecting a liquid crystal compound (ZLI1132, manufactured by Merck & Co., Inc.) having a Δn of 0.1396 into the cell gap.
Polarized light produced using the optical compensation films produced in Examples 1-2, 4-6, and Comparative Examples 1-3 on the upper and lower polarizing plates of the liquid crystal display device using the bend alignment type liquid crystal cell. The plates were attached one by one to the observer side and the backlight side through an adhesive so that the optical compensation film was on the liquid crystal cell side. The optically anisotropic layer of the polarizing plate faced the cell substrate, and the rubbing direction of the liquid crystal cell and the rubbing direction of the optically anisotropic layer facing it were antiparallel. The crossed Nicols were arranged so that the transmission axis of the polarizing plate on the viewer side was in the vertical direction and the transmission axis of the polarizing plate on the backlight side was in the horizontal direction.
The produced liquid crystal panel was allowed to stand in an environment of 25 ° C. and 60% RH for 7 days, and then the display characteristics were evaluated based on the following evaluation criteria. The results are shown in Table 5.

[Evaluation criteria]
Viewing angle (polar angle range with contrast ratio of 10 or more and no black-side gradation inversion)
○: Polar angle of 75 ° or more in the top / bottom / left / right ○ △: Top / bottom / left / right in three directions, polar angle of 75 ° or more △: Top / bottom / left / right, two directions in polar angle of 75 ° or more And polar angle less than 75 °

Next, a rectangular wave voltage of 55 Hz was applied to the liquid crystal cell. A normally white mode of 2V white display and 5V black display was set. A voltage at which the transmittance at the front is minimized, that is, a black voltage is applied, and the black display transmittance (%) at an azimuth angle of 0 ° and a polar angle of 60 ° and a viewing angle of 60 °, and an azimuth angle of 0 ° A color shift Δx with an azimuth angle of 180 ° and a polar angle of 60 ° was determined. The results are shown in Table 3.
In Table 3 below, “color shift” means ΔCu′v ′: u′v ′ (polar angle 60 °) −u′v ′ (polar angle 0 °) and azimuth angle 180 at an azimuth angle of 0 °. ΔCu′v ′ at °: sum of u′v ′ (polar angle 60 °) −u′v ′ (polar angle 0 °). (U'v ': color coordinates in CIELAB space)
Further, using the measuring device (EZ-Contrast 160D, manufactured by ELDIM) as the contrast ratio, the transmittance ratio (white display / black display), the visual field is displayed in eight stages from black display (L1) to white display (L8). The corner was measured. The results are shown in Table 4.
In Table 4 below, “viewing angle” refers to a range in which the contrast ratio is 10 or more and there is no “black-side gradation inversion (inversion between L1 and L2)”.

<< Production of VA Oriented Liquid Crystal Cell >>
The liquid crystal cell has a cell gap between substrates of 3.6 μm, and a liquid crystal material having negative dielectric anisotropy (“MLC6608”, manufactured by Merck & Co., Inc.) is dropped and sealed between the substrates. Prepared by forming a layer. The retardation of the liquid crystal layer (that is, the product Δn · d of the thickness d (μm) of the liquid crystal layer and the refractive index anisotropy Δn) was set to 300 nm. The liquid crystal material was aligned so as to be vertically aligned.

A polarizing plate using the optical compensation film prepared in Examples 3 and 12 and Comparative Example 5 on the upper and lower polarizing plates of the liquid crystal display device using the vertical alignment type liquid crystal cell is used in the polarizing plate. One sheet was attached to the observer side and the backlight side through an adhesive so that the optical compensation film side was opposed to the liquid crystal cell side. The crossed Nicols were arranged so that the transmission axis of the polarizing plate on the viewer side was in the vertical direction and the transmission axis of the polarizing plate on the backlight side was in the horizontal direction.
The produced liquid crystal panel was left in an environment of 25 ° C. and 60% RH for 7 days, and then the display characteristics were evaluated based on the above evaluation criteria. The results are shown in Table 5.

Next, a rectangular wave voltage of 55 Hz was applied to the liquid crystal cell. A normally black mode with 5 V white display and 0 V black display was set. The black display transmittance (%) at the azimuth angle of 0 ° and the polar angle of 60 ° and the color shift Δx between the azimuth angle of 0 ° polar angle of 60 ° and the azimuth angle of 180 ° and polar angle of 60 ° were determined. . The results are shown in Table 3.
Further, using the measuring device (EZ-Contrast 160D, manufactured by ELDIM) as the contrast ratio, the transmittance ratio (white display / black display), the visual field is displayed in eight stages from black display (L1) to white display (L8). The corner was measured. The results are shown in Table 4.

<< Measurement of humidity dependence of display characteristics >>
The liquid crystal panel produced above was left in an environment of 25 ° C. and 10% RH and 25 ° C. and 80% RH for 7 days, and then the display characteristics of the liquid crystal panel were evaluated based on the above evaluation criteria. The results are shown in Table 5.

From the results shown in Tables 2 to 5, the degree of orientation P satisfies 0.05 ≦ P ≦ 0.30, and the optical properties are 10 <Re ₍₅₅₀₎ <100, 100 <Rth ₍₅₅₀₎ <200, _{0.5 <Re (450) / Re} (550) <1.0,1.0 <Re (630) / Re (550) <1.5,1.0 <Rth (450) / Rth (550) < 1.5 and 0.5 <Rth ₍₆₃₀₎ / Rth ₍₅₅₀₎ <The liquid crystal display device provided with the optical compensation film of Examples 1-12 satisfying 1.0 <the optical compensation film of Comparative Examples 1-5 Compared with the liquid crystal display device provided with the above, it can be seen that the transmittance at the time of black display at a polar angle of 60 ° is low and the color shift from the front is small, and the contrast is remarkably improved.

The optical compensation film and polarizing plate of the present invention can improve high contrast and color shift depending on the viewing angle direction during black display, particularly in the VA method, IPS method, and OCB method. It can be suitably used for a liquid crystal display device that is remarkably improved.
The liquid crystal display device of the present invention optically compensates the liquid crystal cell, can improve the contrast, and reduce the color shift depending on the viewing angle direction, and is preferably used for a mobile phone, a monitor for a personal computer, a television, a liquid crystal projector, and the like. be able to.

FIG. 1 is a schematic diagram illustrating a configuration example of a liquid crystal display device of the present invention. FIG. 2 is a graph showing optical characteristics of an example of the optical compensation film used in the present invention. FIG. 3A is a schematic diagram of a Poincare sphere used for explaining a change in the polarization state of incident light in the liquid crystal display device of the present invention. FIG. 3B is a schematic view of a Poincare sphere used for explaining a change in the polarization state of incident light in the liquid crystal display device of the present invention. FIG. 4 is a schematic diagram illustrating a configuration example of a conventional OCB mode liquid crystal display device. FIG. 5A is a schematic diagram of a Poincare sphere used to explain a change in the polarization state of incident light in an example of a conventional liquid crystal display device. FIG. 5B is a schematic diagram of a Poincare sphere used to explain a change in the polarization state of incident light in an example of a conventional liquid crystal display device. FIG. 6A is a schematic diagram of a Poincare sphere used for explaining a change in the polarization state of incident light in the liquid crystal display device of the present invention. FIG. 6B is a schematic diagram of a Poincare sphere used for explaining a change in the polarization state of incident light in the liquid crystal display device of the present invention. FIG. 7A is a diagram showing wavelength dispersion of a film prepared without adding an Rth increasing agent and stretching. FIG. 7B is a diagram showing the wavelength dispersion of a film produced by only stretching without adding an Rth increasing agent. FIG. 7C is a diagram showing wavelength dispersion of a film prepared by adding an Rth increasing agent and further stretching.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Polarizing film 2 Transmission axis 13a Transparent support 14a In-plane slow axis 5 Optically anisotropic layer 5a Orientation average direction 6 on the polarizing film side (interface side of the support) of the molecular symmetry axis of the liquid crystalline compound 6 Substrate 7 Liquid crystal Molecule 8 Substrate 9 Optically anisotropic layer 9a Orientation average direction 101 on the polarizing film side (support interface side) of the molecular symmetry axis of the liquid crystalline compound Polarizing film 102 Transmission axis 113a Transparent support 114a In-plane slow axis

Claims (14)

It has a transparent support containing at least one Rth increasing agent, and the degree of orientation P defined by the following formula (A) calculated from the X-ray diffraction measurement is 0.05 to 0 with respect to the transparent support. 30. An optical compensation film characterized by being 30.
P = <3cos ² β-1> / 2... Formula (A)
However, in the above formula (A), <cos ² β> = ∫ (0, π) cos ² βI (β) sinβdβ / ∫ (0, π) I (β) sinβdβ.
In the above formula, β is an angle formed by the incident surface of the incident X-ray and a certain direction in the surface of the transparent support, and I is 2θ = 8 in the X-ray diffraction chart measured at the angle β. It is the diffraction intensity at °. The optical compensation film according to claim 1, wherein the optical characteristics of one transparent support satisfy the relationships of the following formulas (1) to (6).
10 nm <Re ₍₅₅₀₎ <100 nm... Formula (1)
100 nm <Rth ₍₅₅₀₎ <200 nm (2)
0.5 <Re ₍₄₅₀₎ / Re ₍₅₅₀₎ <1.0 (3)
1.0 <Re ₍₆₃₀₎ / Re ₍₅₅₀₎ <1.5... Equation (4)
1.0 <Rth ₍₄₅₀₎ / Rth ₍₅₅₀₎ <1.5... Formula (5)
0.5 <Rth ₍₆₃₀₎ / Rth ₍₅₅₀₎ <1.0 ... Formula (6)
In the above formulas (1) to (6), Re _(λ) is the retardation value of the transparent support for light with a wavelength of _λ nm, and Rth _(λ) is the transparent support for light with a wavelength of _λ nm. It is the retardation value in the thickness direction of the body. The optical compensation film according to claim 1, wherein the Rth increasing agent is a compound represented by any one of the following general formulas (II) to (V).
However, in the following general formula (II), each R ¹² independently represents an aromatic ring or a heterocyclic ring having a substituent in at least one of the ortho position, the meta position and the para position.
Moreover, X < ¹¹ > represents a single bond or NR < ¹³ >-each independently. Here, each R ¹³ independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an aryl group, or a heterocyclic group.
Moreover, in the following general formula (III), R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ each independently represent a hydrogen atom or a substituent.
In the following general formula (IV), Q ⁷¹ represents a nitrogen-containing aromatic heterocycle, and Q ⁷² represents an aromatic ring.
Further, in the following general formula ^{(V), Q 81} and ^{Q 82} represents an aromatic ring each ^{independently, X 81} is ^NR 81 ^{(R 81} represents a hydrogen atom or a substituent) represents an oxygen atom or a sulfur atom Represents.
  The optical compensation film according to any one of claims 1 to 3, wherein the Rth increasing agent has two or more aromatic rings. 5. The optical compensation film according to claim 1, comprising a compound having a maximum absorption wavelength (λ _max ) of at least 250 nm in the solution absorption spectrum of the Rth increasing agent.   The optical compensation film according to any one of claims 1 to 5, further comprising a humidity dependency improving agent having a hydrogen bonding group in at least one molecule. The optical compensation film according to claim 6, wherein the humidity dependency improving agent has an aromatic ring and satisfies the following formula (7).
Molecular weight of the number of hydrogen bonding groups in one molecule / humidity dependency improver ≧ 0.01 (7) The optical compensation film according to any one of claims 1 to 7, wherein the transparent support is a cellulose acylate film satisfying the following formulas (8) to (9).
2.0 ≤ SA + SB ≤ 3.0 ........................... (8)
0 <SB ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Equation (9)
However, in said formula (8)-(9), SA is the substitution degree of the acetyl group which has substituted the hydrogen atom of the hydroxyl group in a cellulose, SB substituted the hydrogen atom of the hydroxyl group in a cellulose. The substitution degree of the acyl group having 3 to 22 carbon atoms.   A method for producing an optical compensation film according to any one of claims 1 to 8, wherein a polymer solution which is a raw material of a transparent support containing at least one Rth raising agent is cast on a band; A drying step of drying the film produced by the casting step, and a stretching step of peeling the film from the band and then stretching the film at a temperature of +15 to + 100 ° C. than the glass transition temperature of the transparent support. A process for producing an optical compensation film comprising the steps of:   The method for producing an optical compensation film according to claim 9, wherein the drying step has an average drying rate of at least 1.2% by mass / min for a region where the volatile fraction of the film is 10 to 100% by mass.   A polarizing plate having a polarizing film and a pair of protective films sandwiching the polarizing film, wherein at least one of the protective films is the optical compensation film according to any one of claims 1 to 8. A polarizing plate. The coating layer having low moisture permeability is provided on at least one surface of the protective film, and the moisture permeability of the coating layer at 60 ° C and 95% relative humidity is 300 g / m ² · day or less. Polarizer.   A liquid crystal display device comprising a liquid crystal cell and the polarizing plate according to claim 11.   The liquid crystal display device according to claim 13, wherein the liquid crystal cell is a VA method, an OCB method, or an IPS method.