JP7162068B2 - Liquid crystal film, polarizing plate, circularly polarizing plate and image display device - Google Patents

Description

The present invention relates to a liquid crystal film, a polarizing plate, a circularly polarizing plate and an image display device.

Conventionally, liquid crystal films having a liquid crystal layer formed using a polymerizable liquid crystal compound have been used as retardation films and high-performance films. Such a liquid crystal film is produced, for example, by providing a photo-alignment layer on a base material, coating a composition containing a polymerizable liquid crystal compound on the photo-alignment layer, and polymerizing aligned by the alignment regulating force of the photo-alignment layer. It is produced by polymerizing a polar liquid crystal compound to fix the alignment state. At that time, a liquid crystal film having a liquid crystal layer having desired optical properties can be obtained by selecting a polymerizable liquid crystal compound and controlling its alignment state.
For example, Patent Literature 1 describes forming an optically anisotropic layer by forming a layer in which a liquid crystal compound is given a certain orientation.

Moreover, in order to obtain a liquid crystal film with few defects, as described in Patent Document 2, it has been proposed to use a photo-alignment layer instead of the conventionally used rubbing alignment layer. When a photo-alignment layer is used, the process of imparting an alignment regulating force to the photo-alignment layer can be performed in a non-contact manner. Therefore, it is possible to suppress unevenness and defects caused by foreign matter accompanying rubbing.

Display devices to which liquid crystal films are applied include, for example, liquid crystal display devices and organic EL display devices. These display devices are constantly being improved in definition and dynamic range, and there is a constant demand for finer pixel pitch, higher white luminance, and blacker black display performance. In addition, it is required to be visible even in outdoor sunlight or under bright lighting.

Along with such high performance of the display device, the influence of retardation unevenness caused by various factors on the display quality of the display device in addition to defects due to foreign matter in the liquid crystal film is becoming unignorable. Therefore, various methods for suppressing the retardation unevenness of the liquid crystal film have been proposed.

For example, in Patent Document 3, a coating liquid containing a solvent and a liquid crystalline compound is coated on a long substrate, and then the orientation of the liquid crystalline compound in the coating film is fixed to form an optically anisotropic layer. In the method for producing an optical compensation film that forms the surface potential of the substrate and the photo-alignment layer, the coating liquid and the coating environment temperature, the wind speed, and the amount of residual solvent in the coating film and the orientation control conditions are variously adjusted. It is described that an optical compensation film free from unevenness and variation can be obtained.

Further, Patent Document 4 includes a step of applying a coating liquid containing a liquid crystalline compound on a transparent strip-shaped film having an alignment film layer formed thereon, drying the coating layer, and curing the dried coating layer. In the method for producing an optical compensation film, the process from drying until the solid content concentration in the coating layer reaches 80% or more until curing of the coating layer is completed, the strip film in the vicinity of the coating layer of the strip film. A method for producing an optical compensation film is disclosed in which the wind speed of the drying wind component in the width direction is set to 0.7 m/sec or less. It is described that this suppresses the disturbance of the arrangement state of the liquid crystal compound due to the dry air, and reduces the deviation and variation of the slow axis.

JP-A-8-094838 JP-A-2000-086786 Japanese Patent Application Laid-Open No. 2002-277637 Japanese Patent Application Laid-Open No. 2008-224968

In recent years, not only excellent display performance but also thin, lightweight, or bendable display devices have been required. In order to realize such a display device, liquid crystal films are required to have both self-supporting properties and thin base materials. The inventors have made intensive studies to obtain a liquid crystal film using a thin base material, which has been considered difficult to use, and have found that a fine alignment unevenness, which has not been seen in the past, occurs.

For this reason, it has been found that there is a problem that the change in color tone is emphasized and easily recognized when used in a display device with a high dynamic range as described above or in an extremely bright environment that has not been assumed in the past.

Accordingly, an object of the present invention is to provide a thin liquid crystal film, a polarizing plate, a circularly polarizing plate, and an image display device which are thin and have high in-plane uniformity with less uneven alignment. be.

As a result of working to solve the above problems, the inventors have found that the above problems can be solved by the following configuration. That is, the present invention is as follows.

[1] including a photo-alignment layer and a liquid crystal layer in this order on a transparent substrate;
The thickness of the transparent substrate is 10 μm to 25 μm,
A liquid crystal film, wherein the photo-alignment layer is formed from a composition for forming a photo-alignment layer containing an antistatic agent.
[2] The liquid crystal film of [1], wherein the composition for forming a photo-alignment layer contains a photo-aligning polymer.
[3] The liquid crystal film of [2], wherein the photo-orientable polymer comprises any one of an acrylate skeleton, a methacrylate skeleton, a siloxane skeleton, and a polystyrene skeleton.
[4] The liquid crystal film of [2] or [3], wherein the photo-alignable polymer has any one of an acrylate skeleton, a methacrylate skeleton, and a siloxane skeleton.
[5] The liquid crystal film according to any one of [2] to [4], wherein the photo-alignable polymer contains an acrylate skeleton or a methacrylate skeleton.
[6] The liquid crystal film according to any one of [2] to [5], wherein the composition for forming a photo-alignment layer further contains a cross-linking agent and at least one of a cross-linking accelerator and a cross-linking initiator.
[7] The liquid crystal film according to any one of [2] to [6], wherein the composition for forming a photo-alignment layer further contains an acid quencher.
[8] The liquid crystal film according to any one of [1] to [7], wherein the antistatic agent is a low molecular weight ionic compound.
[9] The liquid crystal film of [8], wherein the low-molecular-weight ionic compound comprises an inorganic cation or an organic cation and an organic anion.
[10] The liquid crystal film of [9], wherein the organic anion is bis(fluoroalkylsulfonyl)imide.
[11] The liquid crystal film according to any one of [1] to [10], wherein the transparent substrate and the photo-alignment layer are in direct contact.
[12] The liquid crystal film of any one of [1] to [11], wherein the transparent substrate is a cellulose acylate film containing a polyester additive or a sugar ester compound.
[13] The liquid crystal film of [12], wherein Re(550) of the transparent substrate is 10 nm or less, or Rth(550) of the transparent substrate is -20 nm to 20 nm.
[14] The liquid crystal film according to any one of [1] to [13], wherein Re(550) is 100 nm to 250 nm.
[15] A polarizing plate comprising the liquid crystal film of [14] and a polarizer, wherein the transparent substrate and the polarizer are in contact directly or via an adhesive layer.
[16] The polarizing plate of [15], wherein Re(550) of the liquid crystal film is 120 nm to 160 nm and satisfies the following formulas (1) and (2).
0.6<Re(450)/Re(550)<1.0 (1)
1.0<Re(650)/Re(550)<1.2 (2)
[17] The circularly polarizing plate of [16], wherein the slow axis of the liquid crystal film and the absorption axis of the polarizer intersect at 40° to 50°.
[18] An image display device comprising an antireflection film containing the circularly polarizing plate of [17].

According to the present invention, it is possible to provide a liquid crystal film, a polarizing plate, and an image display device which are thin and have less uneven alignment.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically an example of the liquid crystal film of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram of an example of the manufacturing apparatus which enforces the manufacturing method which manufactures the liquid crystal film of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically an example of the polarizing plate of this invention which has the liquid crystal film of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically an example of the image display apparatus of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. In this specification, a numerical range represented by "-" means a range including the numerical values described before and after it as a lower limit and an upper limit.
In addition, "perpendicular" and "parallel" with respect to angles shall mean a strict angle range of ± 10 °, and "same" and "different" with respect to angles shall mean whether the difference is less than 5 ° can be judged on the basis of
In this specification, "visible light" means 380 nm to 780 nm. In this specification, the measurement wavelength is 550 nm unless otherwise specified.
Next, the terms used in this specification will be explained.

<Lagging axis>
As used herein, the term “slow axis” means the direction in which the refractive index is maximized within the plane. The slow axis of the retardation film means the slow axis of the entire retardation film.

<Re(λ), Rth(λ)>
The values of the in-plane retardation and the retardation in the thickness direction are the values measured using AxoScan OPMF-1 (manufactured by Optoscience) using light of the measurement wavelength.
Specifically, by inputting the average refractive index ((nx+ny+nz)/3) and film thickness (d (μm)) into AxoScan OPMF-1,
Slow axis direction (°)
Re(λ)=R0(λ)
Rth(λ)=((nx+ny)/2−nz)×d
is calculated.
Note that R0(λ), which is displayed as a numerical value calculated by AxoScan OPMF-1, means Re(λ).

[Liquid crystal film]
The liquid crystal film of the present invention comprises a photo-alignment layer and a liquid crystal layer in this order on a transparent substrate,
The thickness of the transparent substrate is 10 μm to 25 μm,
The photo-alignment layer is formed from a composition for forming a photo-alignment layer containing an antistatic agent.
Moreover, the liquid crystal film of the present invention preferably comprises a long transparent substrate, a photo-alignment layer and a liquid crystal layer provided in this order on a long transparent substrate.

This liquid crystal film will be described in detail below. Note that physical property values such as a retardation value and thickness, which will be described later, are those of a portion (typically, the central region in the width direction) that is usually used thereafter.

FIG. 1 is a cross-sectional view schematically showing an example of the liquid crystal film of the present invention. FIG. 1 is a cross-sectional view in a direction perpendicular to the longitudinal direction of the liquid crystal film. The liquid crystal film 10 shown in FIG. 1 has a configuration in which a transparent substrate 1 (hereinafter also referred to as a substrate), a photo-alignment layer 2 and a liquid crystal layer 3 are laminated in this order.
In FIG. 1, the substrate 1, the photo-alignment layer 2, and the liquid crystal layer 3 are drawn to have the same width. 3 is generally provided narrower than the photo-alignment layer 2 . However, if necessary, the liquid crystal layer 3 may be wider than the photo-alignment layer 2 and narrower than the substrate 1 .
In the following description, the direction in which the liquid crystal film extends is defined as the longitudinal direction, and the direction orthogonal to the longitudinal direction is defined as the width direction.

Generally, a liquid crystal film is produced by laminating an alignment film and a liquid crystal layer on a substrate in this order. The alignment film is subjected to an alignment treatment before the liquid crystalline composition forming the liquid crystal layer is applied, and an alignment control force is imparted to the alignment film. get In order to carry out these steps with good productivity and obtain a high-quality and uniform liquid crystal film, it is common to apply a roll-to-roll process. As mentioned above, in order to obtain a uniform and even coating film in the roll-to-roll process, the coating method is devised and the wind speed is controlled in each zone. Also, the alignment of liquid crystal molecules is strictly controlled by precisely controlling the composition and temperature conditions of the composition.

In the roll-to-roll process, peeling electrification is likely to occur when the substrate is fed from the substrate roll, when the web is separated from the transport roll, and when various coating liquids are transferred from the coating head to the web. Such peeling electrification not only causes explosion-proof problems, but also causes unintended surface defects (unevenness and material denaturation) during discharge. Suppression of web charging is performed.

However, in the study of manufacturing a liquid crystal film using a thin base material, the inventors found that the occurrence of conventionally known alignment unevenness can be suppressed by taking these conventionally known measures. It was found that the orientation unevenness could not be eliminated. A detailed analysis of this fine alignment unevenness revealed that only the alignment axis of the liquid crystal layer changed in an unintended direction, without the unevenness of each layer, the denaturation or uneven distribution of substances, and the like.

Although it is not clear how this phenomenon occurs, the inventors believe that when the base material becomes thin, the electrification generated on the surface of the web on the orientation layer side and the surface on the opposite side affect each other. As a result, the direction of the alignment control force of the photo-alignment layer or the alignment direction of the liquid crystal molecules in the polymerizable liquid crystal composition is affected by the electric field caused by the residual charge. It is thought that fine alignment unevenness is induced by being affected and shifted.

In contrast, in the liquid crystal film of the present invention, the photo-alignment layer (composition for forming a photo-alignment layer) contains an antistatic agent. As a result, it is possible to suppress the occurrence of fine alignment unevenness due to electrification of the base material, and to obtain a uniform alignment state without alignment unevenness even with a thin base material, as in the case of using a conventional base material. Therefore, it is possible to obtain a liquid crystal film which is thin, exhibits little change in panel color when incorporated in a display device, and has high in-plane uniformity.

The liquid crystal film of the present invention may have an in-plane retardation of at least Re(550) of 10 nm or more. Preferably, Re(550) is in the range of 100 nm to 250 nm, and within this range, it can be used as various optical compensation films and wavelength plates. More preferably, Re(550) is in the range of 120 nm to 160 nm, and within this range, it can be used as a λ/4 wavelength plate.

Further, with respect to the in-plane retardation of the liquid crystal film, it is preferable that the in-plane retardation at each wavelength satisfies the following relationship.

0.6<Re(450)/Re(550)<1.0
1.0<Re(650)/Re(550)<1.2

When this relationship is satisfied, uniform polarization conversion is possible over a wide band, and when used as various optical compensation films or wavelength plates, good performance with little color change can be exhibited.

<Transparent substrate>
The transparent substrate 1 has a thickness of 10 μm to 25 μm and is transparent. A long shape is preferable in that it is suitable for continuous production and a uniform and high-quality liquid crystal film can be obtained.

Examples of such transparent substrates include cellulose acylate films, acrylic films, polycarbonate films, cycloolefin films, polyethylene terephthalate films, and transparent film materials made of glass. From the viewpoint of thinness, strength, and flexibility, the transparent substrate 1 is preferably a resin film such as a cellulose acylate film, an acrylic film, a polycarbonate film, a cycloolefin film, or a polyethylene terephthalate film.

The transparent substrate 1 preferably has an in-plane retardation Re (550) of 10 nm or less, more preferably 5 nm or less, from the viewpoint of facilitating the control of the polarization state when used as a polarizing plate protective film. It is more preferably 3 nm or less. Although the lower limit is not particularly limited, 0 nm is an example.
Further, from the viewpoint of suppressing the optical influence in the oblique direction, the thickness direction retardation Rth (550) of the transparent substrate 1 is preferably in the range of -20 nm to 20 nm, more preferably in the range of -10 nm to 10 nm. More preferably, it is in the range of -5 nm to 5 nm.

The thickness of the transparent substrate 1 is 10 μm to 25 μm as described above. More preferably, it is 15 μm to 23 μm. Within this range, by devising web handling, the same coatability as in the case of using a substrate having a conventional thickness (typically 40 μm or more) can be ensured.

Further, when the transparent substrate 1 is elongated, its length is preferably 100 m to 10000 m, more preferably 250 m to 7000 m, even more preferably 1000 m to 6000 m. Also, the width is preferably 400 mm to 3000 mm, more preferably 500 mm to 2500 mm, even more preferably 600 mm to 1750 mm. Within this range, even a thin substrate that is inferior in self-supporting property to conventionally known substrates having a thickness of 40 μm to 80 μm while ensuring economic efficiency in the roll-to-roll process can be used for web handling and By devising the winding form, it is possible to produce a liquid crystal film that is excellent in uniformity in the longitudinal and width directions and that suppresses the occurrence of surface defects due to blocking and rubbing that occur in the roll state.

(cellulose acylate film)
A cellulose acylate film can be used as the substrate used in the present invention. It is preferably used because it has both transparency and strength, and even though it is thin, it is more self-supporting than other materials. As the cellulose acylate film, a film containing a cellulose acylate resin and, if necessary, additives can be used. The cellulose acylate film can be produced by solution film forming, or may be produced by melt film forming.

As the cellulose acylate resin, triacetyl cellulose, diacetyl cellulose, and cellulose in which a part of the acetyl group is substituted with a higher acyl group, an aromatic acyl group, an alkoxy group, or a substituted alkoxy group can be used. In the cellulose acylate, the degree of substitution of hydroxyl groups of cellulose is not particularly limited, but in order to impart appropriate moisture permeability and hygroscopicity, the degree of acyl substitution of hydroxyl groups of cellulose should be 2.00 to 3.00. is preferred. Furthermore, the degree of substitution is preferably 2.30 to 2.98, more preferably 2.70 to 2.96, even more preferably 2.80 to 2.94.

As additives, for example, JP-A-2005-154764, JP-A-2013-228720, JP-A-2014-081619, JP-A-2014-178519, JP-A-2015-227956, JP-A-2016- Various additives described in JP-A-2016-164668 and JP-A-2017-106975 can be used.

A preferred example of the additive is a polyester additive having a repeating unit represented by the following general formula (1).

General formula (1)

(In general formula (1), X and Y represent a divalent linking group.)

X includes an alkylene group, polyoxyalkylene group, alkenylene group, phenylene group, naphthylene group, or divalent heterocyclic aromatic group having 2 to 20 carbon atoms, which may have a substituent. . The alkylene group, the alkenylene group, and the alkylene group in the polyoxyalkylene group may have an alicyclic structure.
Y includes an alkylene group having 2 to 20 carbon atoms, a polyoxyalkylene group, an alkenylene group, a phenylene group, a naphthylene group, or a divalent heterocyclic aromatic group, which may have a substituent. . The alkylene group, the alkenylene group, and the alkylene group in the polyoxyalkylene group may have an alicyclic structure.
These divalent linking groups may contain molecules other than carbon such as oxygen atoms and nitrogen atoms. Examples of the substituents described above include alkyl groups, alkoxy groups, hydroxyl groups, alkoxy-substituted alkyl groups, carboxyl groups, and the like.

As the repeating unit represented by the above-described general formula (1), X represents an acyclic divalent linking group having 2 to 10 carbon atoms, and Y represents 3 in terms of excellent retardation properties and elastic modulus of the film. It preferably represents a linking group having 3 to 12 carbon atoms including an alicyclic structure of up to 6-membered rings. The alicyclic structure is preferably a 3- to 6-membered ring, more preferably a 5- to 6-membered ring. Specifically, cyclopropylene group, 1,2-cyclobutylene group, 1,3-cyclobutylene group, 1,2 -cyclopentylene group, 1,3-cyclopentylene group, 1,2-cyclohexylene group, 1,3-cyclohexylene group, and 1,4-cyclohexylene group.

The hydrogen atom at the hydroxyl group terminal of the polyester additive having a repeating unit represented by the general formula (1) may be substituted with an acyl group derived from a monocarboxylic acid (hereinafter also referred to as a monocarboxylic acid residue). (Hereinafter, it is also said that the hydrogen atom at the terminal of the hydroxyl group is blocked). At this time, both ends of the polyester are monocarboxylic acid residues. By protecting the terminal with a hydrophobic functional group, the cohesive force of the additive is suppressed, the compatibility with the film and the handleability of the compound are improved. You can get a good film.

Here, the term "residue" means a partial structure of the polyester and represents a partial structure having the characteristics of the monomers forming the polyester. For example, the monocarboxylic acid residue formed from the monocarboxylic acid R--COOH is R--CO--. Examples of R include an optionally substituted alkyl group having 1 to 10 carbon atoms, an alicyclic alkyl group, and an aromatic group. Preferably, it is an aliphatic monocarboxylic acid residue, more preferably the monocarboxylic acid residue is an aliphatic monocarboxylic acid residue having 2 to 10 carbon atoms, and an aliphatic monocarboxylic acid residue having 2 to 3 carbon atoms. A group is more preferred, and an aliphatic monocarboxylic acid residue having 2 carbon atoms is particularly preferred.

From the viewpoint of improving the durability of the polarizer, the hydroxyl value of the polyester is preferably 10 mgKOH/g or less, more preferably 5 mgKOH/g or less, and particularly preferably 0 mgKOH/g. The number average molecular weight (Mw) of the polyester is preferably 500-3000, more preferably 700-2000. Within this range, it is possible to obtain a stable film with excellent compatibility and less volatilization of additives during film production and use.

Another preferred example of the additive is a compound (sugar ester compound) can be used. More specifically, a compound (M) having 1 to 12 at least one of a pyranose structure or a furanose structure, or a hydroxyl group of a compound (D) in which two at least one of a furanose structure or a pyranose structure are bonded (hereinafter , simply referred to as OH groups) are preferably used.

Examples of compound (M) include glucose, galactose, mannose, fructose, xylose and arabinose, preferably glucose and fructose, more preferably glucose.
Examples of compound (D) include lactose, sucrose, nystose, 1F-fructosylnystose, stachyose, maltitol, lactitol, lactulose, cellobiose, maltose, cellotriose, maltotriose, raffinose and kestose. Also included are gentiobiose, gentiotriose, gentiotetraose, xylotriose, and galactosylsucrose. Among them, glucose, sucrose or lactose is preferred.

It is preferable to use an aliphatic monocarboxylic acid, a monocarboxylic acid having an alicyclic structure, or an aromatic monocarboxylic acid to alkyl-esterify all or part of the OH groups in compound (M) and compound (D). . Such monocarboxylic acids include acetic acid, propionic acid, butyric acid, isobutyric acid, benzoic acid, cyclohexanecarboxylic acid, and the like. Two or more of these monocarboxylic acids may be used in combination.

As other additives, a plasticizer, an ultraviolet absorber, a cross-linking agent, a matting agent (inorganic fine particles such as vapor-phase synthetic silica), an antioxidant, a radical scavenger, and the like may be added. As will be described later, in the case where the substrate of the retardation film of the present invention also serves as a polarizing plate protective film to form a polarizing plate, from the viewpoint of imparting the effect of improving the durability of the polarizer, the following general formula It preferably contains a compound represented by (2).

general formula (2)

(In general formula (2), R ¹¹ , R ¹³ and R ¹⁵ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, or a represents an alkenyl group or an aromatic group having 6 to 20 carbon atoms.)
As such compounds, those described in, for example, International Publication WO2014/112575 can be used.

The cellulose acylate film used in the present invention can be produced using the method described in the Technical Bulletin published by the Institute of Invention and Innovation (public technical number 2001-1745, Institute of Invention and Innovation).
These cellulose acylate films can be obtained by stretching uniaxially or biaxially as necessary, and preferably stretched in the transverse direction. Moreover, it can also be stretched in an oblique direction. The draw ratio in one direction is preferably 1.02 times to 1.50 times, more preferably 1.05 times to 1.30 times. Stretching increases the strength in the stretching direction, so even if the web is thin, the web handleability can be improved.

The cellulose acylate film may have a glass transition temperature (Tg) of 140°C to 200°C, preferably 170°C to 200°C, more preferably 180°C to 200°C, and 185°C. ~200°C is more preferred, and 190°C to 200°C is most preferred. Within this range, the resistance to heat deflection is more excellent, and even if the base material is thin, the alignment state can be controlled precisely and uniformly without any particular difficulty in the liquid crystal film manufacturing process involving heating or the like. It is possible to create a liquid crystal film. The glass transition temperature can be obtained as the peak value of tan δ with a dynamic viscoelasticity measuring device.

<Photo-alignment layer>
The photo-alignment layer 2 used in the present invention is formed from a composition for forming a photo-alignment layer containing an antistatic agent. The photo-alignment layer 2 is formed on the base material 1 and is a layer for orienting the liquid crystal compound of the liquid crystal layer 3 formed on the photo-alignment layer 2 by its alignment control force.

The thickness of the photo-alignment layer is not particularly limited as long as the alignment function can be exhibited, but it is preferably 0.01 μm to 5 μm, more preferably 0.05 μm to 2 μm, and more preferably 0.1 μm to 0.1 μm. More preferably, it is 5 μm. Within this range, an excellent orientation regulating force can be exhibited, and the effect of suppressing foreign matter defects is high.

The substrate 1 and the photo-alignment layer 2 may be provided in direct contact, or a functional layer may be interposed between the substrate 1 and the photo-alignment layer 2 . Such functional layers include a barrier layer, a shock absorbing layer, an easy adhesion layer, and the like.

The photo-alignment layer is preferably formed by applying and drying a composition for forming a photo-alignment layer to form a layer of material that will become the photo-alignment layer on the base material 1, and then irradiating the material layer with linearly polarized ultraviolet rays. As the material for the photo-alignment layer (photo-alignment material), various materials to which the method of photo-alignment can be applied can be applied. can be used. Photoisomerizable materials such as azo compounds can also be suitably used.

From the viewpoint of maintaining the alignment regulating force even under the coating film of the polymerizable liquid crystal composition, the photo-alignment layer is preferably made of a material that is difficult to dissolve and swell by the solvent contained in the polymerizable liquid crystal composition. As such an example, it is preferable to form a photo-alignment layer-forming composition containing a polymer having a photo-alignment group, a cross-linking agent as necessary, and a cross-linking accelerator and a cross-linking reaction initiator as necessary. Moreover, from the viewpoint of achieving close adhesion between the photo-alignment layer and the liquid crystal layer, it is preferable to use a polymer having a photo-alignment group, which has a hydrophobicity close to that of the liquid crystal layer. For example, JP-A-6-289374, JP-A-10-506420, JP-A-2009-501238, JP-A-2012-078421, JP-A-2015-106062, JP-A-2016-079189 Photo-alignable acrylate polymer described in, etc., JP-A-2012-037868, JP-A-2014-026261, JP-A-2015-026050, photo-alignable polysiloxane described in JP-A-2015-151548 JP, JP 2015-151549, JP 2016-098249, etc. Photo-orientable polystyrene-acrylate copolymer described in JP 2012-027471, JP 2015-533883, etc. The described photo-alignable polynorbornene polymer and the like can be used.

The photo-alignment group possessed by the polymer having a photo-alignment group has a photo-alignment function that induces rearrangement or an anisotropic chemical reaction by irradiation with anisotropic light (e.g., plane polarized light). A photo-orienting group is preferable, which causes at least one of dimerization and isomerization by the action of light, from the viewpoint of excellent uniformity of orientation and good thermal and chemical stability.

Photoalignable groups that dimerize under the action of light include, for example, cinnamic acid derivatives (M. Schadt et al., J. Appl. Phys., vol. 31, No. 7, page 2155 (1992)), coumarin Derivatives (M. Schadt et al., Nature., vol. 381, page 212 (1996)), chalcone derivatives (Toshihiro Ogawa et al., Lecture Proceedings of the Liquid Crystal Symposium, 2AB03 (1997)), Maleimide Derivatives, and Benzophenone Derivatives (YK Jang et al., SID Int. Symposium Digest, P-53 (1997)).
On the other hand, examples of photoorientable groups that are isomerized by the action of light include azobenzene compounds (K. Ichimura et al., Mol.Cryst.Liq.Cryst., 298, 221 (1997)), stilbene compounds (JGVictor and JM Torkelson, Macromolecules, 20, 2241 (1987)), spiropyran compounds (K. Ichimura et al., Chemistry Letters, page 1063 (1992); K. Ichimura et al., Thin Solid Films, vol. 235, page 101 (1993) )), cinnamic acid compounds (K. Ichimura et al., Macromolecules, 30, 903 (1997)), and hydrazono-β-ketoester compounds (S. Yamamura et al., Liquid Crystals, vol. 13, No. 2 , page 189 (1993)).

The photo-orientation group is preferably a group having a skeleton of at least one derivative selected from the group consisting of cinnamic acid derivatives, coumarin derivatives, chalcone derivatives, maleimide derivatives, azobenzene compounds, stilbene compounds, and spiropyran compounds. A group having a cinnamic acid derivative skeleton or a coumarin derivative skeleton is more preferable.

The structure of the main chain of the polymer having a photoalignment group is not particularly limited, and includes known structures such as acrylate skeleton, methacrylate skeleton, siloxane skeleton, and polystyrene skeleton, acrylate skeleton, methacrylate skeleton, Alternatively, a siloxane skeleton is preferred, and an acrylate skeleton or methacrylate skeleton is more preferred.
The acrylate skeleton is a skeleton composed of repeating units derived from an acrylate compound (a compound having an acryloyl group). That is, the polymer having a photo-alignment group is preferably a polymer containing a repeating unit derived from an acrylate compound having a photo-orientation group.
A methacrylate skeleton is a skeleton composed of repeating units derived from a methacrylate compound (a compound having a methacryloyl group). That is, the polymer having a photo-alignment group is preferably a polymer containing repeating units derived from a methacrylate compound having a photo-alignment group.
A polystyrene skeleton is a skeleton composed of repeating units derived from styrene. In other words, the polymer having a photo-alignment group is preferably a polymer containing repeating units derived from a styrene compound having a photo-alignment group.
In addition, the siloxane skeleton is a skeleton in which the polymer main chain is composed of Si—O bonds.

A polymer having a repeating unit represented by formula (A) is preferable as the polymer having a photo-orientation group.

In formula (A) above, R ^A1 represents a hydrogen atom or a methyl group.
L ^A1 represents a single bond or a divalent linking group.
The divalent linking group represented by L ^A1 includes, for example, a divalent hydrocarbon group optionally having a substituent (e.g., an alkylene group having 1 to 10 carbon atoms (preferably 1 to 5) , an alkenylene group having 1 to 10 carbon atoms, and a divalent aliphatic hydrocarbon group such as an alkynylene group having 1 to 10 carbon atoms, a divalent aromatic hydrocarbon group such as an arylene group), a divalent heterocyclic ring groups, -O-, -S-, -N(Q)-, -CO-, or groups combining these (e.g., -O-divalent hydrocarbon group -, -(O-divalent hydrocarbon hydrogen group) _p -O- (p represents an integer of 1 or more), and -divalent hydrocarbon group -O-CO-, etc.). Q represents a hydrogen atom or a substituent.
Among them, the divalent linking group represented by L ^A1 is a linear, branched or cyclic alkylene group having 1 to 10 carbon atoms which may have a substituent, and a substituent. an arylene group having 6 to 12 carbon atoms, which may be substituted, -O-, -CO-, and -N(Q)-. Preferably. Q represents a hydrogen atom or a substituent.

R ^A2 , R ^A3 , R ^A4 , R ^A5 and R ^A6 each independently represent a hydrogen atom or a substituent.
R ^A2 , R ^A3 , R ^A4 , R ^A5 and R ^A6 each independently represent a halogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, or a linear alkyl group having 1 to 20 carbon atoms. A chain-like halogenated alkyl group, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a cyano group, an amino group, or the following formula (3) The groups represented are preferred.

Here, in the above formula (3), * represents a bonding position.
^RA7 represents a monovalent organic group. Examples of monovalent organic groups represented by R ^A7 include linear or cyclic alkyl groups having 1 to 20 carbon atoms.

The photo-alignment material preferably has a cross-linkable group capable of reacting with a cross-linking agent described below. The types of crosslinkable groups are not particularly limited, and include hydroxyl groups, carboxyl groups, amino groups, radically polymerizable groups (e.g., acryloyl groups, methacryloyl groups, vinyl groups, styryl groups, and allyl groups), and cationically polymerizable groups. (eg, epoxy group, epoxycyclohexyl group, and oxetanyl group).
When the photo-alignment material is a polymer having a photo-alignment group as described above, the polymer may have a repeating unit having a cross-linkable group, or the repeating unit having a photo-orientation group as described above is further a cross-linkable group. may have

(crosslinking agent)
In order to suppress dissolution and swelling due to the solvent contained in the photo-alignment film polymerizable liquid crystal composition used in the present invention and to impart mechanical strength to the film, a cross-linking agent can be added as necessary. The cross-linking agent may be a monomer capable of chain polymerization, or may be a polyaddition type composition. Moreover, the above-mentioned photo-orientable polymer may participate in the cross-linking reaction.

Examples of chain-polymerizable monomers include (meth)acrylate compounds, epoxy compounds, oxetane compounds, and the like. A polyfunctional monomer is preferable from the viewpoint of increasing the film strength. In addition, by modifying the photo-orientable polymer described above with a copolymerizable functional group, it may be made copolymerizable with these cross-linking agents.

In the cross-linking reaction, a cross-linking accelerator that accelerates the cross-linking reaction or a cross-linking initiator that initiates the cross-linking reaction itself can be added as necessary. When using the above-mentioned cross-linking agent, it is preferable to include at least one of a cross-linking accelerator and a cross-linking initiator from the viewpoint of increasing the productivity of the film and obtaining a stable and uniform photo-alignment film. In particular, when using a monomer capable of chain polymerization, it is preferable to use various polymerization initiators together as a cross-linking initiator. If it is a (meth)acrylate compound, a photo-radical generator and a thermal radical generator can be used. Moreover, if it is an epoxy compound and an oxetane compound, a photocation generator, a thermal cation generator, and a thermal anion generator can be used. Moreover, when using a photo-radical generator and a photo-cation generator, a sensitizer can be used together.

The amount of the cross-linking agent to be added is preferably 25 to 70% by mass, more preferably 40 to 60% by mass, based on the total solid content of the composition for forming a photo-alignment layer.
In addition, solid content means the material which comprises the photo-alignment layer except a solvent, and even if the property is liquid, it is calculated as solid content.

(Antistatic agent)
The antistatic agent added to the composition for forming the photo-alignment layer used in the present invention has excellent compatibility with the photo-alignment layer, and reduces the electrical resistance of the layer surface without affecting the transparency and durability reliability. Various compounds can be used as long as they are antistatic agents capable of suppressing the localization of electrostatic charges. As an example, a conductive polymer, a polymer having an ionic side chain, a low-molecular-weight ionic compound having a cation (for example, an organic cation or an inorganic cation) and an anion (preferably an organic anion), and the like can be used. A low-molecular-weight ionic compound is preferred from the viewpoint of the hue of the compound and compatibility with the photo-alignment layer.
A low molecular weight ionic compound means an ionic compound having a molecular weight of 1000 or less. An ionic compound is a compound (salt) composed of a cation and an anion.

Examples of anions constituting the low molecular weight ionic compound include methylbenzenesulfonate (CH ₃ (C ₆ H ₄ )SO ₃ ⁻ ), carboxybenzenesulfonate (COOH(C ₆ H ₄ )SO ₃ ⁻ ), benzoate (C ₆ H ₅ COO ⁻ ), perchlorate (ClO ₄ ⁻ ), hydroxide (OH ⁻ ), trifluoroacetate (CF ₃ COO ⁻ ), trifluoromethanesulfonate (CF ₃ SO ₂ ⁻ ), tetrafluoroborate (BF ₄ ⁻ ), tetra benzylborate (B(C ₆ H ₅ ) ₄ ⁻ ), hexafluorophosphate (PF ₆ ⁻ ), bis(trifluoromethanesulfonyl)imide (N(SO ₂ CF ₃ ) ₂ ⁻ ), bis(pentafluoroethanesulfonyl)imide (N(SOC ₂ F ₅ ) ₂ ⁻ ), bis(pentafluoroethanecarbonyl) imide (N(COC ₂ F ₅ ) ₂ ⁻ ), bis(perfluorobutanesulfonyl) imide (N(SO ₂ C ₄ F ₉ ) ₂ ⁻ ), bis(perfluorobutanecarbonyl)imide (N(COC ₄ F ₉ ) ₂ ⁻ ), tris(trifluoromethanesulfonyl)methide (C(SO ₂ CF ₃ ) ₃ ⁻ ), and tris(trifluoromethanecarbonyl)methide ( C(SO ₂ CF ₃ ) ₃ ⁻ ). Bis(trifluoromethanesulfonyl)imide is preferred because of its excellent antistatic performance.

Examples of organic cations or inorganic cations include alkali metal element ions such as lithium ions, sodium ions, and potassium ions, and quaternary ammonium cations, quaternary phosphonium cations, imidazolium cations, pyridinium cations, and , organic onium cations having a nitrogen atom or a phosphorus atom, such as pyrrolidinium-based cations. From the viewpoint of antistatic properties, cations with a small molecular weight that increase the mobility in the matrix are preferable. .
Among them, inorganic cations are preferred, and lithium ions are more preferred.

The amount of the antistatic agent added is preferably 0.5% by mass to 10% by mass, more preferably 1% by mass to 7% by mass, and 1% by mass to the total solid content of the composition for forming a photo-alignment layer. 5% by mass is more preferred. Within this range, a sufficient effect of suppressing alignment unevenness can be obtained, and the alignment state of the liquid crystal molecules in the coating film of the polymerizable liquid crystal composition can be maintained at the same level as in the case of no additive.
In addition, solid content means the material which comprises the photo-alignment layer except a solvent, and even if the property is liquid, it is calculated as solid content.

(acid quencher)
The composition for forming a photo-alignment layer used in the present invention may contain an acid quencher, if necessary. Although the mechanism is not clear, the inclusion of the acid quencher suppresses changes in physical properties over time in the composition for forming a photo-alignment film or in the photo-alignment film, and a stable alignment regulating force can be expressed. A low nucleophilic Lewis base can be used as the acid quencher.

Low nucleophilic Lewis bases include nitrogen-containing compounds such as amine compounds (primary amine compounds, secondary amine compounds, tertiary amine compounds). More specifically, higher tertiary amines such as diisopropylethylamine, diethylpropylamine, and benzyldimethylamine, alkylpiperidine, N,N-dimethylpiperazine, triethylenediamine, diazabicycloundecene, and diazabicyclo Cyclic tertiary amines such as nonene, alkyl-substituted imidazoles, and the like can be used. Also available are onium salts having cations with a higher pKa than the acid component that occurs (or can be assumed to be) in the system.
Among them, the acid quencher is preferably a nitrogen-containing compound, more preferably an amine compound.

As mentioned above, onium salts can also be used as acid quenchers.
Examples of cations constituting the onium salt include ammonium cations, sulfonium cations, and iodonium cations.
Preferred onium salts are compounds represented by general formulas (d1-1) to (d1-3).

In the formula, R ⁵¹ is a hydrocarbon group which may have a substituent, Z ^2c is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent (eg fluorine atom) , R ⁵² is an organic group, Y ³ is a linear, branched or cyclic alkylene group or arylene group, Rf is a hydrocarbon group containing a fluorine atom, M ⁺ is each independently ammonium, sulfonium or iodonium cations.

The amount of the acid quencher added is preferably 0.01% by mass to 1.5% by mass, more preferably 0.05% by mass to 1% by mass, based on the total solid content of the composition for forming a photo-alignment layer. more preferably 0.15% by mass to 0.75% by mass.

Various additives may be further added to the composition for forming a photo-alignment layer. Examples of such additives include acid generators (e.g., thermal acid generators), UV (ultraviolet) absorbers, reaction sensitizers for photoalignment groups, leveling agents, and low-molecular-weight photoreactive group-containing compounds. mentioned.

<Liquid crystal layer>
The liquid crystal layer 3 is a layer formed on the substrate 1 (photo-alignment layer 2) using a polymerizable liquid crystal composition containing a liquid crystal compound. The liquid crystal layer 3 is formed by curing the liquid crystal compound to be the liquid crystal layer 3 in an aligned state by the alignment control force of the photo-alignment layer 2 . Therefore, the liquid crystal layer 3 has optical characteristics according to the alignment state of the liquid crystal compound.

The liquid crystal layer 3 can have an in-plane retardation of at least Re(550) of 10 nm or more. Preferably, Re(550) is in the range of 100 nm to 250 nm, and within this range, it can be used as various optical compensation films and wavelength plates. More preferably, Re(550) is in the range of 120 nm to 160 nm, and within this range, it can be used as a λ/4 wavelength plate.
In the case of a λ/4 wavelength plate in which the liquid crystal layer 3 is manufactured in a long shape, a polarizer film also manufactured in a long shape (generally, the absorption axis is parallel to the longitudinal direction or parallel to the width direction It is preferable that the slow axis forms 40° to 50° with respect to the longitudinal direction of the base material 1, and forms 45° because it is easy to obtain a circularly polarizing plate when combined with is more preferred.

The refractive index anisotropy Δn of the liquid crystal layer 3 at a wavelength of 550 nm is preferably in the range of 0.03 to 0.25, more preferably in the range of 0.05 to 0.20. Within this range, it is possible to obtain a desired high retardation with a thin liquid crystal layer. The thickness of the liquid crystal layer 3 can be appropriately set depending on the refractive index anisotropy and the desired retardation value, and is typically in the range of 0.5 μm to 7 μm, more preferably 0.7 μm to 5 μm. More preferably, it is in the range of 1.0 μm to 3.0 μm.

Regarding the in-plane retardation Re of the liquid crystal layer 3 , the in-plane retardation at each wavelength preferably satisfies the relationship Re(450)<Re(550)<Re(650).
When this relationship is satisfied, uniform polarization conversion is possible over a wide band, and when used as various optical compensation films or wavelength plates, good performance with little tint can be exhibited. More preferably, it satisfies the relationships of the following formulas (1) and (2). Such a liquid crystal layer can be obtained by using a reverse wavelength dispersion polymerizable liquid crystal compound described later.

0.6<Re(450)/Re(550)<1.0
1.0<Re(650)/Re(550)<1.2

<<polymerizable liquid crystal composition>>
The polymerizable liquid crystal composition used in the present invention exhibits liquid crystallinity and includes a polymerizable liquid crystal compound having a polymerizable functional group in the molecule, other polymerizable compounds, an alignment stabilizer, a polymerization initiator, and a solvent. etc. may be included.

(Polymerizable liquid crystal compound)
The polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition has refractive index anisotropy and is regularly aligned by the alignment control force of the photo-alignment layer 2, thereby providing a desired retardation property. have. Polymerizable liquid crystal compounds include, for example, materials exhibiting liquid crystal phases such as nematic phases and smectic phases. In addition, polymerizable liquid crystal molecules having various structures such as rod-like liquid crystal compounds and discotic liquid crystal compounds can be used.

As the polymerizable liquid crystal compound used in the present embodiment, JP-A-8-050206, JP-A-2007-002220, JP-A-2010-244038, JP-A-2008-019240, JP-A-2013-166879 Publications, JP 2014-078036, JP 2014-198813, JP 2011-006360, JP 2011-6361, JP 2011-207765, JP 2008-273925, Compounds and the like described in JP-A-2015-200877 can be used. A plurality of different polymerizable liquid crystal compounds can be mixed and used from the viewpoint of obtaining a liquid crystal film having a more excellent surface state by adjusting the phase transition temperature and suppressing the crystallization of the polymerizable liquid crystal compound.

When the liquid crystal film of the present invention is used as a wave plate or the like, a polymerizable liquid crystal compound having reverse wavelength dispersion can be used as the polymerizable liquid crystal compound. A polymerizable liquid crystal compound having reverse wavelength dispersion is used to measure the retardation at a specific wavelength (visible light range) of the retardation layer produced using this, typically the in-plane retardation (Re) value. When measured, the Re value becomes equal or higher as the measurement wavelength increases, and as described above, it means a substance that satisfies the relationship Re(450)<Re(550)<Re(650).

Reverse wavelength dispersion liquid crystal compounds are, for example, compounds represented by general formula (I) described in JP-A-2008-297210 (especially compounds described in paragraphs [0034] to [0039]), Compounds represented by the general formula (1) described in JP-A-2010-084032 (in particular, compounds described in paragraph numbers [0067] to [0073]), liquid crystal compounds represented by the general formula (II) described later etc. can be used.

From the viewpoint of being more excellent in reverse wavelength dispersion, the reverse wavelength dispersion liquid crystal compound described above preferably contains a liquid crystal compound represented by the following general formula (II).

L ₁ -G ₁ -D ₁ -Ar-D ₂ -G ₂ -L ₂ General formula (II)

In the above general formula (II), D ₁ and D ₂ are each independently a single bond, -O-, -CO-O-, -C(=S)O-, -CR ¹ R ² -, -CR ¹ R ² -CR ³ R ⁴ -, -O-CR ^{1 R 2 -, -CR 1 R 2 -O-CR 3 R 4 -, -CO-O-CR 1 R 2 - , -O - CO -} CR ¹ R ² -, -CR ¹ R ² -O-CO-CR ³ R ⁴ -, -CR ¹ R ² -CO-O-CR ³ R ⁴ -, -NR ¹ -CR ² R ³ - or -CO-NR ¹ represents -.
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom, a fluorine atom or an alkyl group having 1 to 4 carbon atoms. When there are a plurality of each of R ¹ , R ² , R ³ and R ⁴ , the plurality of R ¹ s, the plurality of R ² , the plurality of R ³ and the plurality of R ⁴ may be the same or different from each other. good.
G ₁ and G ₂ each independently represent a divalent alicyclic hydrocarbon group having 5 to 8 carbon atoms, and the methylene groups contained in the alicyclic hydrocarbon groups are —O—, —S—, Alternatively, it may be substituted with -NH-.
L ₁ and L ₂ each independently represent a monovalent organic group, and at least one selected from the group consisting of L ₁ and L ₂ represents a monovalent group having a polymerizable group.
Ar represents a divalent aromatic ring group represented by the following general formula (II-1), general formula (II-2), general formula (II-3) or general formula (II-4).

In general formulas (II-1) to (II-4) above, Q ₁ represents -S-, -O-, or -NR ¹¹ -,
R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms,
Y ₁ represents an aromatic hydrocarbon group having 6 to 12 carbon atoms or an aromatic heterocyclic group having 3 to 12 carbon atoms (the above aromatic hydrocarbon group and the above aromatic heterocyclic group are substituents ),
Z ₁ , Z ₂ and Z ₃ are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a monovalent represents an aromatic hydrocarbon group, a halogen atom, a cyano group, a nitro group, —NR ¹² R ¹³ or —SR ¹² ,
Z ₁ and Z ₂ may combine with each other to form an aromatic ring or an aromatic heterocyclic ring, R ¹² and R ¹³ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms,
A ₁ and A ₂ are each independently a group selected from the group consisting of —O—, —NR ²¹ —, —S— and —CO—, wherein R ²¹ represents a hydrogen atom or a substituent, and X is a hydrogen atom or a nonmetallic atom of groups 14 to 16 to which a substituent may be bound (preferably =O, =S, =NR', =C(R')R' (where R ' represents a substituent)),
Ax represents an organic group having 2 to 30 carbon atoms having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring, preferably an aromatic hydrocarbon ring group; A heterocyclic group; an alkyl group having 3 to 20 carbon atoms having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring; a group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring An alkenyl group having 3 to 20 carbon atoms having at least one aromatic ring selected from; Alkenyl groups include
Ay is a hydrogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms, or a carbon having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring represents an organic group of numbers 2 to 30, the preferred embodiment of this organic group is the same as the preferred embodiment of the organic group of Ax above,
each of the aromatic rings in Ax and Ay may have a substituent, and Ax and Ay may combine to form a ring,
Q ₂ represents a hydrogen atom or an optionally substituted alkyl group having 1 to 6 carbon atoms.
The substituents include halogen atoms, alkyl groups, halogenated alkyl groups, alkenyl groups, aryl groups, cyano groups, amino groups, nitro groups, nitroso groups, carboxy groups, alkylsulfinyl groups having 1 to 6 carbon atoms, carbon an alkylsulfonyl group having 1 to 6 carbon atoms, a fluoroalkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylsulfanyl group having 1 to 6 carbon atoms, an N-alkylamino group having 1 to 6 carbon atoms, N,N-dialkylamino group having 2 to 12 carbon atoms, N-alkylsulfamoyl group having 1 to 6 carbon atoms, N,N-dialkylsulfamoyl group having 2 to 12 carbon atoms, or a combination thereof etc.

For the definition and preferred range of each substituent of the liquid crystal compound represented by general formula (II), D ¹ , D ² , G ¹ , G ² , The descriptions of L ¹ , L ² , R ⁴ , R ⁵ , R ⁶ , R ⁷ , X ¹ , Y ¹ , Q ¹ and Q ² are respectively D ₁ , D ₂ , G ₁ , G ₂ , L ₁ and L ₂ , R ¹ , R ² , R ³ , R ⁴ , Q ₁ , Y ₁ , Z ₁ , and Z ₂ , and for compounds represented by general formula (I) described in JP-A-2008-107767 A ₁ , A ₂ , and X can be referred to for A ₁ , A ₂ , and X, respectively, and Ax, Ay for compounds represented by general formula (I) described in WO 2013/018526 , Q ¹ can be referred to for Ax, Ay, Q ₂ respectively. For Z ₃ , the description of Q ¹ regarding compound (A) described in JP-A-2012-21068 can be referred to.

In particular, the organic groups represented by L ₁ and L ₂ are each preferably a group represented by -D ₃ -G ₃ -Sp-P ₃ .
_D3 is _synonymous with D1.
G ₃ represents a single bond, a divalent aromatic or heterocyclic group having 6 to 12 carbon atoms, or a divalent alicyclic hydrocarbon group having 5 to 8 carbon atoms, and the above alicyclic hydrocarbon group The methylene group contained in may be substituted with —O—, —S—, or —NR ⁷ —, where R ⁷ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
Sp is a single bond, -(CH ₂ ) _n -, -(CH ₂ ) _n -O-, -(CH ₂ -O-) _n -, -(CH ₂ CH ₂ -O-) _m , -O- (CH ₂ ) _n —, —O—(CH ₂ ) _n —O—, —O—(CH ₂ —O—) _n —, —O—(CH ₂ CH ₂ —O—) _m , —C(= O)-O-(CH ₂ ) _n -, -C(=O)-O-(CH ₂ ) _n -O-, -C(=O)-O-(CH ₂ -O-) _n -,- C(=O)-O-(CH ₂ CH ₂ -O-) _m , -C(=O)-N(R ⁸ )-(CH ₂ ) _n -, -C(=O)-N(R ⁸ )-(CH ₂ ) _n -O-, -C(=O)-N(R ⁸ )-(CH ₂ -O-) _n -, -C(=O)-N(R ⁸ )-(CH ₂ a spacer group represented by CH ₂ —O—) _m , —(CH ₂ ) _n —O—(C=O)—(CH ₂ ) _n —C(=O)—O—(CH ₂ ) _n — show. Here, n represents an integer of 2 to 12, m represents an integer of 2 to 6, and R ⁸ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Also, the hydrogen atom of —CH ₂ — in each of the above groups may be substituted with a methyl group.
_P3 represents a polymerizable group.

The polymerizable group is not particularly limited, but is preferably a polymerizable group capable of radical polymerization or cationic polymerization.
As the radically polymerizable group, generally known radically polymerizable groups can be used, and acryloyl groups and methacryloyl groups can be mentioned as suitable groups. In this case, it is known that acryloyl groups generally have a high polymerization rate, and acryloyl groups are preferable from the viewpoint of improving productivity. can be done.
As the cationically polymerizable group, generally known cationically polymerizable groups can be used. Specifically, alicyclic ether groups, cyclic acetal groups, cyclic lactone groups, cyclic thioether groups, spiroorthoester groups, and , a vinyloxy group. Among them, an alicyclic ether group and a vinyloxy group are preferable, and an epoxy group, an oxetanyl group and a vinyloxy group are particularly preferable.
Examples of particularly preferred polymerizable groups include the following.

In this specification, the "alkyl group" may be linear, branched, or cyclic, and examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, 1,1-dimethylpropyl group, n-hexyl group, isohexyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, and a cyclohexyl group and the like.

Preferred examples of the liquid crystal compound represented by formula (II) are shown below, but the liquid crystal compound is not limited to these.

In addition, in the above formula, "*" represents a bonding position.

The reverse wavelength dispersion polymerizable liquid crystal compound described above can be used in combination with different polymerizable liquid crystal compounds for the purpose of adjusting the phase transition temperature, controlling the degree of wavelength dispersion, and controlling the film quality. preferable. The polymerizable liquid crystal compound to be used in combination is not particularly limited, and different kinds of known polymerizable liquid crystal compounds and the reverse wavelength dispersion polymerizable liquid crystal compounds described above can be combined. Precipitation can be suppressed by using a plurality of types of compounds having liquid crystallinity. It is preferable to mix three or more kinds of liquid crystals, and it is more preferable to mix five or more kinds of liquid crystals.

(Other polymerizable compounds)
As the polymerizable compound contained in the polymerizable liquid crystal composition, a non-liquid crystal polyfunctional polymerizable compound can be preferably included. Examples of such non-liquid crystalline polyfunctional polymerizable compounds include known ester compounds of polyhydric alcohols and (meth)acrylic acid. Addition of these compounds increases the fluidity of the polymerizable liquid crystal composition and promotes leveling, so that the liquid crystal layer 3 with less retardation unevenness can be obtained. In addition, by adjusting the number of polymerizable functional groups, the wet heat durability of the liquid crystal layer 3 can be improved, and the scratch resistance and film strength can be enhanced.

(Orientation stabilizer)
The polymerizable liquid crystal composition may contain an alignment stabilizer. By using an alignment stabilizer, various disturbing factors are suppressed, the alignment of the liquid crystalline compound is stabilized, and the liquid crystal layer 3 with little retardation unevenness can be obtained. Moreover, by appropriately selecting the structure of the alignment stabilizer, the alignment of the liquid crystal layer can be adjusted to any alignment such as horizontal alignment, vertical alignment, hybrid alignment, cholesteric alignment, and the like. From the viewpoint of achieving both alignment stabilization and leveling, it is particularly preferable to use acrylic polymers having fluoroaliphatic side chains (paragraphs 0022 to 0063 of JP-A-2008-257205, paragraph 0017 of JP-A-2006-91732 ~0124) can be added.

(Polymerization initiator)
The polymerizable liquid crystal composition forming the liquid crystal layer may contain a polymerization initiator.
The polymerization initiator used is preferably a photopolymerization initiator capable of initiating the polymerization reaction by irradiation with ultraviolet rays.
Examples of photopolymerization initiators include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ethers (described in US Pat. No. 2,448,828), and α-hydrocarbon-substituted aromatic compounds. group acyloin compounds (described in US Pat. No. 2,722,512), polynuclear quinone compounds (described in US Pat. No. 3549367), acridine and phenazine compounds (Japanese Patent Application Laid-Open No. 60-105667, US Pat. No. 4,239,850) and oxadiazole compounds (US Pat. No. 4,212,970), acylphosphine Oxide compounds (described in JP-B-63-40799, JP-B-5-29234, JP-A-10-95788, JP-A-10-29997) and the like.

In the present invention, the polymerization initiator is preferably an oxime-type polymerization initiator (described in U.S. Pat. No. 5,496,482) because the durability of the liquid crystal layer is improved. A polymerization initiator represented by formula (III) is more preferred.

Here, in the above formula (III), X represents a hydrogen atom or a halogen atom, and Y represents a monovalent organic group.
Ar ³ represents a divalent aromatic group, L ⁶ represents a divalent organic group having 1 to 12 carbon atoms, and R ¹⁰ represents an alkyl group having 1 to 12 carbon atoms.

In the above formula (III), the halogen atom represented by X includes, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. Among them, a chlorine atom is preferred.
In the above formula (III), the divalent aromatic group represented by Ar ³ is selected from the group consisting of the aromatic hydrocarbon rings and aromatic heterocycles exemplified as Ar ² in the above formula (II). A divalent group having at least one aromatic ring and the like are included.
In the above formula (III), the divalent organic group having 1 to 12 carbon atoms represented by L ⁶ includes, for example, a linear or branched alkylene group having 1 to 12 carbon atoms. preferably includes a methylene group, an ethylene group, a propylene group, and the like.
Further, in the above formula (III), specific examples of the alkyl group having 1 to 12 carbon atoms represented by R ¹⁰ preferably include a methyl group, an ethyl group, and a propyl group.
In the above formula (III), the monovalent organic group represented by Y includes, for example, a functional group containing a benzophenone skeleton ((C ₆ H ₅ ) ₂ CO). Specifically, a functional group containing a benzophenone skeleton having an unsubstituted or monosubstituted terminal benzene ring, such as groups represented by the following formulas (2a) and (2b), is preferred.

Here, in the above formulas (3a) and (3b), * represents the bonding position, that is, the bonding position with the carbon atom of the carbonyl group in the above formula (III).

Examples of the oxime-type polymerization initiator represented by the formula (III) include compounds represented by the following formula S-1 and compounds represented by the following formula S-2.

In the present invention, the content of the polymerization initiator is not particularly limited. parts to 10 parts by mass, more preferably 0.2 parts to 1 part by mass.

(solvent)
The polymerizable liquid crystal composition preferably contains an organic solvent from the viewpoint of workability for forming a liquid crystal layer.
Specific examples of organic solvents include ketones (eg, acetone, 2-butanone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, etc.), ethers (eg, dioxane, tetrahydrofuran, etc.), aliphatic Hydrocarbons (e.g., hexane, etc.), alicyclic hydrocarbons (e.g., cyclohexane, etc.), aromatic hydrocarbons (e.g., toluene, xylene, trimethylbenzene, etc.), halogenated carbons (e.g., dichloromethane, dichloroethane, etc.) , dichlorobenzene, chlorotoluene, etc.), esters (e.g., methyl acetate, ethyl acetate, butyl acetate, etc.), water, alcohols (e.g., ethanol, isopropanol, butanol, cyclohexanol, etc.), cellosolves (e.g., methyl cellosolve , ethyl cellosolve, etc.), cellosolve acetates, sulfoxides (e.g., dimethylsulfoxide, etc.), amides (e.g., dimethylformamide, dimethylacetamide, etc.). The above may be used in combination.

The amount of solvent in the polymerizable liquid crystalline composition is preferably between 50% and 90% by mass, more preferably between 60% and 85% by mass, relative to the total amount of the composition. Within this range, the film exhibits excellent leveling properties and has an appropriate viscosity, so that it is less likely to be disturbed by external factors, and film thickness variations due to film thickness unevenness can be effectively suppressed.

(other ingredients)
The polymerizable liquid crystal composition may contain components other than those mentioned above, and examples thereof include plasticizers, ultraviolet absorbers, dyes, radical quenchers, and the like.

[Method for producing liquid crystal film]
The method for producing the liquid crystal film of the present invention is not particularly limited, and includes known methods.
Typically,
The composition for forming a photo-alignment layer is applied directly onto a transparent substrate or, if necessary, via a functional layer to form a coating film, and the resulting coating film is irradiated with polarized light to regulate the alignment. a step of applying a force to obtain a photo-alignment film;
The polymerizable liquid crystal composition is applied on the obtained photo-alignment film to form a coating film, and the resulting coating film is subjected to curing treatment (irradiation of active energy rays (light irradiation treatment) and / or heat treatment ),
are performed in this order, the liquid crystal film of the present invention can be produced. In order to carry out these processes with good productivity and obtain a high-quality and uniform liquid crystal film, a roll-to-roll process is applied, and a series of processes are continuously performed on a long transparent substrate to form a long transparent substrate. It is preferable to produce a liquid crystal film of

FIG. 2 is a diagram schematically showing a roll-to-roll manufacturing apparatus for carrying out the liquid crystal film manufacturing method of the present invention.
Manufacturing apparatus 30 shown in FIG. 62.
This manufacturing apparatus 30 sequentially forms the photo-alignment layer 2 and the liquid crystal layer 3 while transporting the substrate 1 along a predetermined transport path in the longitudinal direction.

The rotating shaft 60 is loaded with the substrate roll 31 around which the substrate 1 is wound. The take-up shaft 62 is a known elongated take-up shaft for taking up the substrate 1 after forming the photo-alignment layer 2 and the liquid crystal layer 3 . The backup roll 38 is a backup roll that supports the long base material 1 from the back side during the formation of the photo-alignment layer 2 (light irradiation).

The coating part 32 is a part for coating (applying) the coating liquid to be the photo-alignment layer 2 onto the substrate 1 . The coating portion 35 is a portion for coating the photo-alignment layer 2 formed on the substrate 1 with the coating liquid that will form the liquid crystal layer 3 .
The coating method for the coating portion 32 and the coating portion 35 is not limited, and a coating method capable of coating the photo-alignment layer 2 and the liquid crystal layer 3 to desired thicknesses, respectively, may be used. Therefore, known coating methods such as die coating, dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, and slide coating can all be used.
Among them, the die coating method is preferable because the coating liquid can be applied in a non-contact manner, so that the surface of the substrate 1 is not damaged, and the bead formation is excellent in embedding the unevenness of the surface of the substrate 1. used.

The heating part 33 and the heating part 36 are parts for heating and drying the coating liquid layer to be the photo-alignment layer 2 or the liquid crystal layer 3 coated on the substrate 1, respectively.
The drying method by the heating unit 33 and the heating unit 36 is not limited. All known drying means are available. As an example, drying by heating with a heater, drying by heating with hot air, and the like are exemplified.

The light sources 34 and 37 irradiate the dried coating liquid layer or the coating liquid layer with ultraviolet light, visible light, or the like, respectively, to crosslink organic compounds such as monomers contained in the coating liquid layer and the coating liquid layer. It is cured to form the photo-alignment layer 2 or the liquid crystal layer 3 .
The wavelength of the light emitted by the light source may be set according to the material contained in the coating liquid, the material contained in the coating liquid, and the like. The light source is not limited as long as it can irradiate light of a set wavelength, and known light sources used in liquid crystal film manufacturing apparatuses can be used as appropriate.

In addition to the illustrated members, the manufacturing apparatus 30 conveys a long base material such as a conveying roller, a guide member for regulating the position of the base material 1 in the width direction, various sensors, and a static eliminator. At the same time, it may have various members provided in a known device for forming a liquid crystal layer.

Next, each step of the manufacturing method of the liquid crystal film of the present invention performed by the manufacturing apparatus 30 shown in FIG. 2 will be described.
First, as a preparation step, a substrate roll 31 around which a transparent substrate 1 having a thickness of 10 μm to 25 μm is wound is prepared.
The base material roll 31 is set on the rotating shaft 60 , and the base material 1 is pulled out from the base material roll 31 and passed through a predetermined conveying path from the rotating shaft 60 to the take-up shaft 62 .

Moreover, the composition for forming the photo-alignment layer 2 which is prepared in advance is supplied to the application section 32 . Similarly, a previously prepared polymerizable liquid crystal composition for forming the liquid crystal layer 3 is supplied to the coating section 35 .

In the manufacturing apparatus 30, feeding of the base material 1 from the base material roll 31 and winding of the base material 1 on which the liquid crystal layer 3 has been formed are synchronously carried out on the take-up shaft 62, and the base material 1 is conveyed in a predetermined manner. Formation of the photo-alignment layer 2 (orientation process) and formation of the liquid crystal layer 3 (coating process, liquid crystal layer formation process) are continuously performed while conveying in the longitudinal direction along the path.

The photo-alignment layer 2 is formed by performing an alignment step in the manufacturing apparatus 30 .
Specifically, the coating section 32 arranged in the middle of the transport path of the base material 1 coats the base material 1 with the coating liquid that will become the photo-alignment layer 2 . Next, the heating unit 33 arranged downstream of the coating unit 32 heats and dries the coated coating liquid layer that will become the photo-alignment layer 2 . Next, the light source 34 disposed downstream of the heating unit 33 irradiates linearly polarized ultraviolet rays to cure the coating liquid layer, thereby forming the photo-alignment layer 2 . At this time, the exposure from the light source 34 is prevented from vibrating the web using a backup roll 38 .

Next, as a coating step, the coating section 35 arranged on the downstream side of the light source 34 coats the coating liquid to be the liquid crystal layer 3 onto the substrate 1 (photo-alignment layer 2).
Next, as a liquid crystal layer forming step, the heating unit 36 disposed downstream of the coating unit 35 heats and dries the coated liquid layer that will become the liquid crystal layer 3 . If necessary, further heating or cooling can be performed to promote the alignment of the liquid crystal compound contained in the polymerizable liquid crystalline composition or to adjust the alignment state.

Among these series of steps, the surface potential of the transparent base material and the photo-alignment film can be controlled by providing static eliminators before and after the separation part from the transport roll and the area where the coating bead contacts. Such measures can be carried out as a range that can be generally carried out in order to improve explosion-proof safety. It is possible to adjust the location and various conditions for static elimination.

Furthermore, the light source 37 disposed downstream of the heating unit 36 irradiates ultraviolet rays, and the liquid crystal compound is cured in an aligned state by the alignment control force of the photo-alignment layer 2 to form the liquid crystal layer 3 . Here, the irradiation of ultraviolet rays by the light source 37 is performed from the side of the coating liquid layer that becomes the liquid crystal layer 3 . When irradiating with ultraviolet rays, the atmosphere may be replaced with nitrogen.

Next, as a winding step, the substrate 1 on which the photo-alignment layer 2 and the liquid crystal layer 3 are formed, that is, the liquid crystal film 10 is wound around the winding shaft 62 .
The wound liquid crystal film roll 39 is subjected to the next step as required.

In the example shown in FIG. 2, the photo-alignment layer 2 and the liquid crystal layer 3 are formed continuously in one transport path. 3 may be formed by a different manufacturing apparatus.

Here, as described above, separation electrification occurs when the substrate is delivered from the substrate roll, when the substrate is separated from the transport roll, or the like. In particular, when the transparent base material 1 is thin, the base materials or the base material and the roll are likely to stick to each other. In addition, when the base material is thin, the effect of static elimination is limited, and local electrification tends to remain. Fine orientation unevenness is induced by being disturbed by the influence of the electric field caused by the

In contrast, in the liquid crystal film of the present invention, the composition for forming a photo-alignment layer contains an antistatic agent. As a result, it is possible to suppress the occurrence of fine alignment unevenness due to electrification of the base material, and to obtain a uniform alignment state without alignment unevenness even with a thin base material.

[Optical parts]
By combining with a polarizer, the liquid crystal film of the present invention can be used as an optical component (for example, a polarizing plate) that can be used in various display devices. In combination, various adhesives can be used for lamination. Examples of such adhesives include ultraviolet curable resins, thermosetting resins, and pressure-sensitive adhesives.

<Polarizing plate>
The polarizing plate of the present invention has the liquid crystal film described above and a polarizer.
FIG. 3 is a schematic diagram showing an example of the polarizing plate of the present invention.
A polarizing plate 20 shown in FIG. 3 has a liquid crystal film 10 and a polarizer 21 laminated on the transparent substrate 1 side of the liquid crystal film 10 .

Thus, the polarizing plate 20 can be constructed by laminating the liquid crystal film of the present invention and the polarizer. For example, when the polarizing plate 20 is configured as a circular polarizing plate, the in-plane retardation Re(550) of the liquid crystal film of the invention is preferably in the range of 120 nm to 160 nm, more preferably in the range of 130 nm to 150 nm. Further, it is preferable to dispose the slow axis of the liquid crystal film of the present invention so as to intersect the absorption axis of the linear polarizing plate at 40° to 50°. More preferably, the slow axis of the liquid crystal film and the absorption axis of the linear polarizing plate are arranged at 45°. When the liquid crystal film of the present invention is elongated, the slow axis of the liquid crystal film is set at 45° with respect to the conveying direction, and the elongated polarizer 21 having an absorption axis in the width direction, or an absorption in the conveying direction A long circularly polarizing plate can be manufactured with good productivity by laminating the long polarizer 21 having an axis. In addition, since the liquid crystal film of the present invention satisfies the above formulas (1) and (2), the circularly polarizing plate of the present invention can be used as a circularly polarizing plate that provides uniform circularly polarized light over a wide band.

The structure of the polarizing plate of the present invention is not limited to the above. By variously controlling the directional retardation Rth(550) and wavelength dispersion, it can be used as various optical compensation films.

The polarizer 21 used in the polarizing plate of the present invention is typically composed of an optical functional layer that functions as a polarizer and, if necessary, a protective film. Examples of materials for the protective film include TAC (triacetylcellulose), acrylic resins such as polymethyl (meth)acrylate and copolymers thereof, epoxy compounds, crosslinked polymer resins such as (meth)acrylate compounds, and cycloolefins. Resins such as resins, polycarbonate resins, and glass can be applied. Typically, it is possible to use a laminate obtained by sandwiching an optical function layer made of stretched PVA to which iodine is adsorbed by a pair of protective films and interposing an adhesive layer therebetween.

When constructing the polarizing plate of the present invention, the substrate of the liquid crystal film is used as a protective film, and the optical function layer (polarizer), the transparent substrate 1, the photo-alignment layer 2, and the liquid crystal layer 3 are laminated in this order. can be The optical function layer is typically produced by adsorbing and orienting iodine compound molecules on a film material made of polyvinyl alcohol (PVA) as described above. A film, a layer in which an organic dichroic dye is blended in a liquid crystal composition and oriented, a layer in which a liquid crystalline organic dichroic dye is oriented, or the like may be used. As the adhesive layer (not shown) for lamination, various known adhesives described above can be used.

The polarizing plate of the present invention may further include a positive C plate having a thickness direction retardation (Rth(550)) of −150 nm to −50 nm at a wavelength of 550 nm. By including the positive C plate, it is possible to further suppress light leakage and coloring in the oblique direction of the display device.
The thickness direction retardation (Rth(550)) of the positive C plate at a wavelength of 550 nm is -150 nm to -50 nm, preferably -130 nm to -60 nm, more preferably -120 nm to -70 nm.

Although the thickness of the positive C plate is not particularly limited, it is preferably 0.5 μm to 10 μm, more preferably 0.5 μm to 5 μm, from the viewpoint of thinning. When providing the positive C plate, only the positive C plate may be provided independently by transfer or coating, but other functional layers may be provided together with the positive C plate as necessary. Such functional layers include protective films, hard coat layers, and cushion layers. As the protective film, each film exemplified as the protective film for the polarizer described above can be used.

Although the material constituting the positive C plate is not particularly limited, it is preferably formed from a composition containing a liquid crystal compound. Forming from a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound is preferable from the viewpoint of increasing the durability over time and the degree of alignment order. Such a positive C plate can typically be obtained by vertically aligning a rod-like polymerizable liquid crystal compound contained in a polymerizable liquid crystal composition and fixing the alignment state by polymerization. Moreover, it can also be formed from a composition containing a side-chain type polymer liquid crystal compound as the liquid crystal compound.

(other optical components)
The liquid crystal film of the present invention can be applied not only to circularly polarizing plates but also to various optical components. Examples thereof include polarizing plates with optical compensation layers for liquid crystal display devices, polarized sunglasses, brightness enhancement plates, decorative films, viewing angle limiting films, and light control films. The optical properties and the average slow axis direction of the liquid crystal film of the present invention can be changed variously according to the application without departing from the gist of the present invention.

[Image display device]
The image display device of the present invention is an image display device including the polarizing plate. By appropriately cutting the polarizing plate and mounting it on the display device, an image display device with excellent display quality can be configured. For example, by arranging it between a liquid crystal display panel and a polarizer, it is possible to improve the viewing angle characteristics of the liquid crystal display device as an optical compensation film. Moreover, it can be used as an antireflection film provided in an organic EL display device to prevent internal reflected light.

FIG. 4 is a cross-sectional view schematically showing an example of the image display device of the present invention. The image display device 50 shown in FIG. 4 has an antireflection film 52 cut out from the polarizing plate 20 on the panel surface (viewer side) of the image display panel 51 . The antireflection film 52 is a circularly polarizing plate containing the liquid crystal film of the present invention described above, and prevents internal reflected light.
The image display panel 51 is an organic EL panel, for example, and displays a desired color image. The image display panel 51 is not limited to the organic EL panel, and various image display panels such as a liquid crystal display panel can be widely applied.

The antireflection film 52 is typically attached and held to the panel surface of the image display panel 51 by an adhesive layer 53 . The antireflection film 52 is configured by laminating and integrating the linear polarizer 21 and the liquid crystal film 10 having the characteristics of a λ/4 wavelength plate with the adhesive layer 22 . A known adhesive can be used for the adhesive layer 53 and the adhesive layer 22 .

The liquid crystal film, polarizing plate, circularly polarizing plate, and image display device of the present invention have been described in detail above, but the present invention is not limited to the above embodiments, and various improvements can be made without departing from the scope of the present invention. and may make changes.

The invention will be described in detail below with reference to examples.

[Preparation of Cellulose Acylate Film 1]
(Preparation of Core Layer Cellulose Acylate Dope)
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a cellulose acetate solution used as the core layer cellulose acylate dope 1 .
──────────────────────────────────
Core layer cellulose acylate dope 1
──────────────────────────────────
・100 parts by mass of cellulose acetate having a degree of acetyl substitution of 2.88 ・12 parts by mass of polyester compound B described in Examples of JP-A-2015-227955 ・2 parts by mass of compound F below ・Methylene chloride (first solvent) 500 parts by mass, methanol (second solvent) 75 parts by mass────────────────────────────────────

Compound F

(Preparation of outer layer cellulose acylate dope)
To 90 parts by mass of the core layer cellulose acylate dope was added 10 parts by mass of the following matting agent solution to prepare a cellulose acetate solution used as the outer layer cellulose acylate dope.
──────────────────────────────────
Matting agent solution ────────────────────────────────────
・Silica particles with an average particle size of 20 nm (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) 2 parts by mass ・Methylene chloride (first solvent) 76 parts by mass ・Methanol (second solvent) 11 parts by mass ・The above core layer cellulose acetate Rate dope 1 part by mass────────────────────────────────────

(Formation of Cellulose Acylate Film 1)
The core layer cellulose acylate dope 1 and the outer layer cellulose acylate dope were filtered through a filter paper having an average pore size of 34 μm and a sintered metal filter having an average pore size of 10 μm. Three layers of the rate dope were simultaneously cast onto a metal band at 20°C from a casting port (band casting machine).

After casting, the formed membrane (film) is peeled off from the metal band in a state where the solvent content is about 20% by mass, both ends of the film in the width direction are fixed with tenter clips, and the film is stretched in the horizontal direction at a magnification of 1.1 times. It was dried while being stretched at Thereafter, the obtained film was further dried by being transported between rolls of a heat treatment apparatus, and wound up to prepare a long cellulose acylate film 1 having a thickness of 20 μm. The core layer of the film had a thickness of 16 μm, and the outer layers disposed on both sides of the core layer each had a thickness of 2 μm. The in-plane retardation of the obtained cellulose acylate film 1 was 0 nm. Tg was 182°C.

(Preparation of cellulose acylate film 2)
Cellulose Acylate Film 2 was prepared in the same manner as Cellulose Acylate Film 1, except that the formulation of the core layer dope was changed as follows. The in-plane retardation of the obtained cellulose acylate film 1 was 2 nm. Moreover, Tg was 193 degreeC.
──────────────────────────────────
Core layer cellulose acylate dope 2
──────────────────────────────────
・100 parts by mass of cellulose acetate having a degree of acetyl substitution of 2.88 ・11 parts by mass of polyester compound B described in Examples of JP-A-2015-227955 ・500 parts by mass of methylene chloride (first solvent) ・Methanol (second Solvent) 75 parts by mass ────────────────────────────────────

(Preparation of Cellulose Acylate Film 3)
Cellulose Acylate Film 3 was prepared in the same manner as Cellulose Acylate Film 1, except that the formulation of the core layer dope was changed as follows. The in-plane retardation of the obtained cellulose acylate film 1 was 0 nm. Moreover, Tg was 185 degreeC.
──────────────────────────────────
Core layer cellulose acylate dope 3
──────────────────────────────────
- Cellulose acetate having a degree of acetyl substitution of 2.88 100 parts by mass - Sugar ester compound S1 9.3 parts by mass - Sugar ester compound S2 3.1 parts by mass - Methylene chloride (first solvent) 500 parts by mass - Methanol (second solvent ) 75 parts by mass──────────────────────────────────

(Preparation of Cellulose Acylate Film 4)
Cellulose Acylate Film 3 was prepared in the same manner as Cellulose Acylate Film 1, except that the formulation of the core layer dope was changed as follows. The in-plane retardation of the obtained cellulose acylate film 1 was 0 nm. Moreover, Tg was 175 degreeC.
──────────────────────────────────
Core layer cellulose acylate dope 4
──────────────────────────────────
・100 parts by mass of cellulose acetate having a degree of acetyl substitution of 2.88 ・9.5 parts by mass of triphenyl phosphate ・4.5 parts by mass of biphenyldiphenyl phosphate ・500 parts by mass of methylene chloride (first solvent) ・Methanol (second solvent ) 75 parts by mass──────────────────────────────────

(Synthesis of polymer A1 having photoalignable group)
A flask equipped with a condenser and a stirrer was charged with 1 part by mass of 2,2′-azobis(isobutyronitrile) as a polymerization initiator and 180 parts by mass of diethylene glycol methyl ethyl ether as a solvent. 100 parts by mass of 3,4-epoxycyclohexylmethyl methacrylate was added thereto, and the inside of the flask was replaced with nitrogen, followed by gentle stirring. The solution temperature was raised to 80° C. and maintained at this temperature for 5 hours to obtain a polymer solution containing about 35% by weight of polymethacrylate having epoxy groups. The weight average molecular weight Mw of the resulting epoxy-containing polymethacrylate was 25,000.
Next, in another reaction vessel, 286 parts by mass of the solution containing the epoxy-containing polymethacrylate obtained above (100 parts by mass in terms of polymethacrylate) obtained by the method of Synthesis Example 1 of JP-A-2015-026050. 120 parts by mass of the obtained cinnamic acid derivative, 20 parts by mass of tetrabutylammonium bromide as a catalyst, and 150 parts by mass of propylene glycol monomethyl ether acetate as a dilution solvent were charged, and the reaction was allowed to proceed under a nitrogen atmosphere at 90°C for 12 hours with stirring. gone. After completion of the reaction, the reaction mixture was diluted by adding 100 parts by mass of propylene glycol monomethyl ether acetate, and washed with water three times. The organic phase after washing with water was poured into a large excess of methanol to precipitate the polymer, and the collected precipitate was vacuum-dried at 40° C. for 12 hours to obtain the following polymer A1 having a photoalignable group. .

(Example 1)
[Preparation of liquid crystal film]
On one side of the cellulose acylate film 1 prepared above, the following composition 1 for photo-alignment film was continuously applied using a bar coater. After coating, the coating was dried in a heating zone at 120° C. for 1 minute to remove the solvent and form a photoisomerizable composition layer having a thickness of 0.3 μm. Subsequently, while being wrapped around a mirror-finished backup roll, it was irradiated with polarized ultraviolet rays (10 mJ/cm ² , using an ultra-high pressure mercury lamp) so that the polarization axis formed an angle of 45° in the longitudinal direction, thereby producing a long light beam. An alignment film was formed.

──────────────────────────────────
Composition 1 for optical alignment film
──────────────────────────────────
100 parts by mass of the polymer A1 having a photo-orientable group Nomcoat TAB (manufactured by Nisshin OilliO Co., Ltd.) 15.2 parts by weight of a cross-linking agent (Epolead GT401, manufactured by Daicel Corporation)
122 parts by mass Thermal acid generator (San-Aid SI-60, manufactured by Sanshin Chemical Industry Co., Ltd.)
5.5 parts by mass Trifluoromethanesulfonic acid sulfonium salt (CPI-110TF, manufactured by San-Apro Co., Ltd.) 1.0 parts by mass Lithium bis(trifluoromethanesulfonyl)imide 5.0 parts by mass Butyl acetate 3000 parts by mass ---- ――――――――――――――――――――――――――――

NOMCOAT TAB

Subsequently, a previously prepared polymerizable liquid crystal composition 1 described below was applied onto the elongated photo-alignment film using a die coater to form a liquid crystal layer (uncured).

―――――――――――――――――――――――――――――――――
Polymerizable liquid crystal composition (liquid crystal 1)
―――――――――――――――――――――――――――――――――
42.00 parts by mass of the following liquid crystalline compound L-3 42.00 parts by mass of the following liquid crystalline compound L-4 16.00 parts by mass of the following polymerizable compound A-1 The following polymerization initiator S-1 (oxime type ) 0.50 parts by mass Leveling agent (Compound G-1 below) 0.20 parts by mass Hisolve MTEM (manufactured by Toho Chemical Industry Co., Ltd.) 2.00 parts by mass NK Ester A-200 (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) 1.00 parts by mass Methyl ethyl ketone 305.9 parts by mass Cyclopentanone 118.9 parts by mass ――――――――――――――――――――――――――――― ――――
The group adjacent to the acryloyloxy group in the liquid crystal compounds L-3 and L-4 below represents a propylene group (a group in which a methyl group is substituted with an ethylene group), and the liquid crystal compounds L-3 and L-4 below. represents a mixture of positional isomers that differ in the position of the methyl group.

Liquid crystal compound L-3

Liquid crystal compound L-4

Polymerizable compound A-1

Polymerization initiator S-1

Compound G-1

The formed liquid crystal layer (uncured) was once heated to 110° C. in a heating zone and then cooled to 75° C. to stabilize the alignment.
After that, the temperature is maintained at 75° C., and the orientation is fixed by ultraviolet irradiation (500 mJ/cm ² , using an ultra-high pressure mercury lamp) in a nitrogen atmosphere (oxygen concentration: 100 ppm) to form a liquid crystal layer (hardened) with a thickness of 2.3 μm. Then, this was wound up on a winding shaft to produce a liquid crystal film.
The average in-plane retardation Re(550) of the obtained liquid crystal film satisfies Re(450)/Re(550)<1.0 and 1.0<Re(650)/Re(550) at 140 nm, The average slow axis direction was 45° with respect to the longitudinal direction.

[Examples 2 to 25, Comparative Example 1]
A liquid crystal film was produced in the same manner as in Example 1, except that the ratio of each component used in the composition for forming a photo-alignment layer was changed as shown in Table 1.
Lithium bis(trifluoromethanesulfonyl)imide is abbreviated as Li-TFSI.

In addition, in Table 1, the polymer A2 of the composition for forming a photo-alignment film is the following copolymer A2. In Example 12, the polymer of Production Example 1 described in JP-A-2016-098249 was used instead of A1 as the polymer of the composition for forming a photo-alignment film. Further, in Example 13, the liquid crystal aligning agent A-4 described in JP-A-2014-026261 was used instead of A1 as the polymer of the composition for forming a photo-alignment film. Further, in Example 14, ROP-103 manufactured by Rolic Co., Ltd. was used instead of A1 as the polymer of the composition for forming a photo-alignment film.

Copolymer A2 (weight average molecular weight Mw: 35000)

（上記式中、各繰り返し単位に付された数値は、各繰り返し単位の質量％を表す。）

(In the above formula, the numerical value attached to each repeating unit represents the mass% of each repeating unit.)

In Table 1, K-FSI of the antistatic agent of the composition for forming a photo-alignment film is potassium bis(fluorosulfonyl)imide.
In Examples 4 to 20 and Comparative Example 1, diisopropylethylamine was used as the acid quencher of the composition for forming a photo-alignment film instead of CPI-110TF.

The polymerizable liquid crystal compositions represented by liquid crystals 2 to 4 in Table 1 have the following compositions.

―――――――――――――――――――――――――――――――――
Polymerizable liquid crystal composition (liquid crystal 2)
―――――――――――――――――――――――――――――――――
・The following liquid crystalline compound 4 100.0 parts by mass ・The above polymerization initiator S-1 1.0 parts by mass ・Leveling agent (the above compound G-1) 0.40 parts by mass ・Cyclopentanone 259 parts by mass ―――――――――――――――――――――――――――――

Liquid crystalline compound 4

―――――――――――――――――――――――――――――――
Polymerizable liquid crystal composition (liquid crystal 3)
―――――――――――――――――――――――――――――――
・Polymerizable liquid crystal compound L-1 39.00 parts by mass ・Polymerizable liquid crystal compound L-2 39.00 parts by mass ・Polymerizable liquid crystal compound L-5 17.00 parts by mass ・Polymerizable liquid crystal compound A-1 5.00 Parts by mass · 0.50 parts by mass of the following polymerization initiator S-1 · Leveling agent (G-1) 0.20 parts by mass · Cyclopentanone 235.00 parts by mass ――――――――――――― ――――――――――――――――――

Polymerizable liquid crystal compound L-1

Polymerizable liquid crystal compound L-2

Polymerizable liquid crystal compound L-5

―――――――――――――――――――――――――――――――――
Polymerizable liquid crystal composition (liquid crystal 4)
―――――――――――――――――――――――――――――――――
・The liquid crystalline compound L-1 10.00 parts by mass ・The liquid crystalline compound L-2 10.00 parts by mass ・The liquid crystalline compound L-3 30.00 parts by mass ・The liquid crystalline compound L-4 40.00 Parts by mass Polymerizable compound A-1 10.00 parts by mass Polymerization initiator S-1 (oxime type) 0.50 parts by mass Leveling agent (Compound G-1 above) 0.20 parts by mass Hisolve MTEM (manufactured by Toho Chemical Industry Co., Ltd.) 2.00 parts by mass NK Ester A-200 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 1.00 parts by mass KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.) 5.00 parts by mass Methyl ethyl ketone 305. 9 parts by mass Cyclopentanone 118.9 parts by mass ――――――――――――――――――――――――――――――――――

[Examples 1a to 25a, Comparative Example 1a]
Each example except that the composition for forming a photo-alignment layer used in each example and comparative example was sealed in a nitrogen-filled sealed light-shielding container immediately after preparation and stored for 10 days before use. A photo-alignment layer and a liquid crystal film were prepared in the same manner as in the comparative example.

[evaluation]
A film having a width of 40 mm and a length of 40 mm was cut out from the liquid crystal film obtained in each example and comparative example. The sample was observed with a polarizing microscope (using a 10-fold objective lens) under crossed Nicols to confirm liquid crystal alignment.

(Evaluation of orientation unevenness)
The number of alignment irregularities was counted when an area of 1.5 m ² of the liquid crystal film of each example and comparative example was observed with a Schaukasten.
a: not seen at all b: 1 to 10 c: 11 to 30 d: 31 or more a to c have no practical problem.

(Evaluation in OLED panel mounting)
The obtained liquid crystal film of Example 1 was subjected to a roll-to-roll process with the cellulose acylate film side of the liquid crystal film facing the polarizing plate side, and the cellulose acylate film 1 also serving as a polarizing plate protective film. After being laminated with a plate (the absorption axis of which is in the longitudinal direction), it was once wound up to produce the polarizing plate 1 of the present invention. Further, the polarizing plate 1 was unwound and cut into a predetermined shape to obtain a circularly polarizing plate 1 . On the liquid crystal layer side surface of the obtained circularly polarizing plate 1, a positive C plate described in paragraphs 0124 to 0127 of Example 0124 of JP-A-2015-200861 (provided that Rth at 550 nm is −65 nm, The thickness of the positive C plate is controlled) was transferred and laminated to obtain a laminate 1. The angle formed by the in-plane slow axis of the retardation film and the transmission axis of the linear polarizing plate was 45°.

Next, the GALAXY SII manufactured by SAMSUNG equipped with an organic EL panel is disassembled, the circularly polarizing plate is peeled off, and the same shape and the same transmission axis direction as the circularly polarizing plate taken out from the laminated body 1 prepared above. An OLED display device was produced by pasting the cut laminate pieces via an adhesive so that the positive C plate side faced the panel side.

Instead of the retardation film of Example 1, except that each liquid crystal film obtained in Examples 2 to 20 and 1a to 20a, Comparative Examples 1 and 1a was used in the same manner as described above Mounting evaluation in an OLED display device did

(Reflectance)
The reflectance of the produced OLED display device was evaluated under bright light. Using a calorimeter (CM-2022, manufactured by Konica Minolta), measurement was performed in SCE (Specular component excluded) mode, and the obtained Y value was evaluated according to the following criteria based on Example 20.
A lower reflectance means less light leakage from the liquid crystal film. That is, it means that the alignment state of the liquid crystal molecules in the liquid crystal layer of the liquid crystal film is good.

A: With respect to the Y value in Example 20, when the ratio of the Y value is 70% or less B: With respect to the Y value in Example 20, when the ratio of the Y value is more than 70% and 90% or less C : When the ratio of the Y value is more than 90% with respect to the Y value in Example 20

When the formed liquid crystal layer (uncured) was once heated to 110° C. in a heating zone, the appearance of wrinkles was observed.

(transportability)
The presence or absence of wrinkles due to transport was checked during the production of the liquid crystal films of each of the examples and comparative examples. Transportability was evaluated according to the following criteria.
A: No wrinkles during transportation B: Intermittent weak wrinkles with an amplitude of less than 1 cm during transportation C: Continuous weak wrinkles with an amplitude of less than 1 cm during transportation D: Amplitude of 1 cm or more during transportation A strong wrinkle is seen.
Table 2 shows the results.

From Tables 1 and 2, it can be seen that Examples 1 to 20 containing an antistatic agent in the photo-alignment film-forming composition have less alignment unevenness than Comparative Example 1.

Moreover, from the comparison with Examples 1, 2, 4 and 20, etc., it can be seen that the content of the antistatic agent is preferably 15% or less with respect to the total solid content of the composition for forming a photo-alignment layer.
Moreover, from the comparison between Example 7 and Example 16, it is found that the antistatic agent containing lithium ions as cations is preferable as the antistatic agent.
Further, from the comparison of Examples 7, 12 to 14, and 17, it can be seen that the photoalignable polymer preferably contains any one of an acrylate skeleton, a methacrylate skeleton, a siloxane skeleton, and a polystyrene skeleton.

Further, from the comparison of Examples 15a and 21a to 23a, it can be seen that it is preferable to contain an acid quencher.

Also, from the comparison of the types of transparent substrates, it can be seen that the higher the Tg, the better the transportability.
From the above results, the effect of the present invention is clear.

REFERENCE SIGNS LIST 1 transparent substrate 2 photo-alignment layer 3 liquid crystal layer 10 liquid crystal film 20 polarizing plate 21 polarizer (optical function layer)
22 Adhesive Layer 30 Liquid Crystal Film Manufacturing Apparatus 31 Base Rolls 32, 35 Coating Sections 33, 36 Heating Sections 34, 37 Light Sources 38 Backup Rolls 39 Liquid Crystal Film Rolls 50 Image Display Device 51 Image Display Panel 52 Antireflection Film 53 Adhesive Layer 60 Rotating shaft 62 Winding shaft

Claims (17)

comprising a photo-alignment layer and a liquid crystal layer in this order on a transparent substrate;
The transparent substrate has a thickness of 10 μm to 25 μm,
The photo-alignment layer is formed from a composition for forming a photo-alignment layer containing an antistatic agent,
the photo-alignment layer comprises an acid quencher;
The liquid crystal film , wherein the acid quencher is an amine compound . 2. The liquid crystal film according to claim 1, wherein the composition for forming a photo-alignment layer contains a photo-aligning polymer. 3. The liquid crystal film according to claim 2, wherein said photo-orientable polymer comprises any one of an acrylate skeleton, a methacrylate skeleton, a siloxane skeleton and a polystyrene skeleton. 4. The liquid crystal film according to claim 2, wherein the photo-orientable polymer has any one of an acrylate skeleton, a methacrylate skeleton, and a siloxane skeleton. 5. The liquid crystal film according to any one of claims 2 to 4, wherein the photo-orientable polymer comprises an acrylate backbone or a methacrylate backbone. 6. The liquid crystal film according to any one of claims 2 to 5, wherein the composition for forming a photo-alignment layer further comprises a cross-linking agent and at least one of a cross-linking accelerator and a cross-linking initiator. The liquid crystal film according to any one of claims 1 to 6, wherein the antistatic agent is a low molecular weight ionic compound. 8. The liquid crystal film according to claim 7, wherein said low molecular weight ionic compound comprises an inorganic cation or an organic cation and an organic anion. 9. The liquid crystal film according to claim 8, wherein said organic anion is bis(fluoroalkylsulfonyl)imide. The liquid crystal film according to any one of claims 1 to 9, wherein the transparent substrate and the photo-alignment layer are in direct contact. 11. The liquid crystal film according to any one of claims 1 to 10, wherein the transparent substrate is a cellulose acylate film containing a polyester additive or a sugar ester compound. 12. The liquid crystal film according to claim 11, wherein Re(550) of said transparent base material is 10 nm or less, or Rth(550) of said transparent base material is -20 nm to 20 nm. The liquid crystal film according to any one of claims 1 to 12, wherein Re(550) is from 100 nm to 250 nm. A polarizing plate comprising the liquid crystal film according to claim 13 and a polarizer, wherein the transparent substrate and the polarizer are in contact directly or via an adhesive layer. 15. The polarizing plate according to claim 14, wherein the liquid crystal film has Re(550) of 120 nm to 160 nm and satisfies the following formulas (1) and (2).
0.6<Re(450)/Re(550)<1.0 (1)
1.0<Re(650)/Re(550)<1.2 (2) 16. The circularly polarizing plate according to claim 15, wherein the slow axis of the liquid crystal film and the absorption axis of the polarizer intersect at 40° to 50°. An image display device comprising an antireflection film comprising the circularly polarizing plate according to claim 16 .

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