WO2019082745A1

WO2019082745A1 - Polarizing film and method for manufacturing same

Info

Publication number: WO2019082745A1
Application number: PCT/JP2018/038525
Authority: WO
Inventors: 伸行幡中; 耕太村野
Original assignee: 住友化学株式会社
Priority date: 2017-10-27
Filing date: 2018-10-16
Publication date: 2019-05-02
Also published as: KR20200080245A; JPWO2019082745A1; CN111279231A; JP2023080141A; TW201923393A

Abstract

This polarizing film comprises a liquid crystal layer. The liquid crystal layer contains a liquid crystal compound, and comprises at least two regions that are distinguished by color correction polarization value. The at least two regions have different dichroic pigment contents.

Description

Polarized film and method of manufacturing the same

The present invention relates to a polarizing film and a method for producing the same, and more particularly to a polarizing film having a layer containing a liquid crystal compound and a dichroic dye and a method for producing the same.

An organic EL display device using an organic light emitting diode (OLED) can not only be reduced in weight and thickness as compared with a liquid crystal display device, but also has high image quality such as wide viewing angle, fast response speed, and high contrast. Because it can be realized, it is used in various fields such as smartphones, televisions, digital cameras, and the like. In the organic EL display device, it is known to improve the antireflection performance by using a circularly polarizing plate or the like in order to suppress a decrease in visibility due to the reflection of external light.

As a polarizing film used for such a circularly polarizing plate, in JP-A-2015-206852 (patent document 1) and JP-A-2015-212823 (patent document 2), liquid crystal cured on a substrate is cured. A patterned polarizing film having a laminated film is described.

JP, 2015-206852, A JP, 2015-212823, A

An object of the present invention is to provide a novel polarizing film having at least two regions in which values of the degree of visibility correction polarization are different from each other, and a method of manufacturing the same.

The present invention provides a polarizing film shown below and a method for producing the same.
[1] A polarizing film having a liquid crystal layer, which is
The liquid crystal layer contains a liquid crystal compound and has at least two regions distinguished by the value of the degree of polarization correction for polarization,
The polarizing film, wherein the at least two regions have different dichroic dye contents.
[2] Furthermore, a base material layer,
An orientation layer laminated on at least one side of the substrate layer,
The polarizing film according to [1], wherein the liquid crystal layer is laminated on the alignment layer.
[3] The polarizing film according to [2], wherein the alignment layer contains a photoalignable polymer.
[4] The polarizing film according to any one of [1] to [3], wherein the liquid crystal compound comprises a polymerizable liquid crystal compound.
[5] The liquid crystal layer has a first region containing a dichroic dye, and a second region in which the content of the dichroic dye is smaller than that of the first region,
The visibility correction polarization degree of the first area is 90% or more.
The polarizing film according to any one of [1] to [4], wherein the visibility correction polarization degree of the second region is 10% or less.
[6] The liquid crystal layer has a first region containing a dichroic dye, and a second region containing a smaller amount of dichroic dye than the first region,
The visibility correction single transmittance of the first region is 35% or more,
The polarizing film according to any one of [1] to [5], wherein the transmittance of the second region in the second region is 80% or more.
[7] The second region is circular, elliptical, oval or polygonal in a plan view shape,
When the second region is circular, the diameter is 5 cm or less.
When the second region is elliptical or oblong, the major axis is 5 cm or less.
The polarizing film according to any one of [5] or [6], wherein a diameter of a virtual circle drawn so that the polygon is inscribed is 5 cm or less when the second region is a polygon.
[8] The polarizing film according to any one of [5] to [7], wherein the first region exhibits a Bragg peak in X-ray diffraction measurement.
[9] Furthermore, it has a base material layer,
The polarizing film according to any one of [1] to [8], wherein the base material layer has a quarter wavelength plate function.
[10] The polarizing film according to any one of [1] to [9], wherein the length of the polarizing film is 10 m or more.
[11] A circularly polarizing plate formed by laminating the polarizing film as described in any one of [1] to [8] and [10] and a retardation layer having a 1⁄4 wavelength plate function.
[12] A preparing step of preparing a laminated film having a polarizing layer containing a liquid crystal compound and a dichroic dye on at least one side of a substrate layer.
A dichroic dye in a partial region of the polarizing layer is brought into contact with a partial region of the polarizing layer of the laminated film by bringing a liquid capable of reducing the content of the dichroic dye in the polarizing layer into contact. And D. a liquid contacting step of reducing the content of.
[13] The liquid contacting step is
A protective layer is formed on the polarizing layer of the laminated film prepared in the preparation step, by laminating a protective layer having a coated area for covering the polarizing layer and an exposed area for exposing the polarizing layer. A protective layer laminating step of obtaining a laminated film
By bringing the laminated film with the protective layer into contact with a liquid capable of reducing the content of the dichroic dye in the polarizing layer, the content of the dichroic dye is reduced in a partial region of the polarizing layer A decoloring process to obtain a decolorized laminated film,
The peeling process of peeling the said protective layer from the said decolorized laminated film, The manufacturing method of the polarizing film as described in [12].
[14] The exposed area in the protective layer is circular, elliptical, oval or polygonal in a plan view shape,
When the exposed area is circular, the diameter is 5 cm or less.
When the exposed area is elliptical or oval, the major axis is 5 cm or less.
The manufacturing method of the polarizing film as described in [13] whose diameter of the virtual circle drawn so that the said polygon may be inscribed is 5 cm or less, when the said exposure area | region is a polygon.
[15] The preparation step is
An alignment layer forming step of coating the composition for forming an alignment layer on one side of the base material layer to form an alignment layer;
A polarizing layer forming step of applying the composition for forming a polarizing layer containing the liquid crystal compound and the dichroic dye on the surface of the base layer on which the alignment layer is formed, thereby forming the polarizing layer; , The manufacturing method of the polarizing film in any one of [12]-[14].
[16] The composition for forming an alignment layer contains a photoalignable polymer,
The polarizing film according to [15], wherein the step of forming an alignment layer is performed by irradiating polarized light on the coating layer for an alignment layer formed by applying the composition for forming an alignment layer to form an alignment layer. Production method.
[17] The liquid crystal compound is a polymerizable liquid crystal compound,
In the polarizing layer forming step, the polarizing layer is formed by applying an active energy ray to the coating layer for a polarizing layer formed by applying the composition for forming a polarizing layer, [15] or [16] The manufacturing method of the polarizing film as described in-.
[18] The method for producing a polarizing film according to any one of [12] to [17], wherein the polarizing film has a length of 10 m or more.
[19] A retardation layer laminating step of laminating a polarizing film produced by the method for producing a polarizing film according to any one of [12] to [18] and a retardation layer having a quarter wave plate function The manufacturing method of the circularly-polarizing plate to have.
[20] The polarizing film is a long polarizing film having a length of 10 m or more,
The retardation layer is a long retardation layer having a length of 10 m or more,
In the retardation layer laminating step, an elongated laminate is formed by laminating the elongated polarizing film and the elongated retardation layer.
Furthermore, the manufacturing method of the circularly-polarizing plate as described in [19] which has a cutting process which cut | judges the said elongate laminated body to a sheet.

According to the present invention, it is possible to provide a polarizing film having at least two regions having mutually different values of the degree of visibility correction polarization, and a method of manufacturing the same.

(A) is a schematic plan view which shows an example of the polarizing film of this invention, (b) is XX sectional drawing of (a). (A) to (c) are each a schematic cross-sectional view showing an example of the circularly polarizing plate of the present invention. (A) to (d) are schematic cross-sectional views showing an example of the layer structure obtained in each step of the process for producing a polarizing film of the present invention. It is a schematic sectional drawing which shows an example of the liquid thing contact process in the manufacturing method of the polarizing film of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the polarizing film of the present invention and the method for producing the same will be described below with reference to the drawings. The scope of the present invention is not limited to the embodiments described herein, and various modifications can be made without departing from the spirit of the present invention.

<Polarizing film>
FIG. 1 (a) is a schematic plan view showing an example of the polarizing film of the present invention, and FIG. 1 (b) is a sectional view taken along the line XX in FIG. 1 (a). The polarizing film 1 of the present embodiment is a film having the function of light absorption anisotropy, and has a liquid crystal layer 11 containing a liquid crystal compound. The liquid crystal layer 11 has at least two regions distinguished by the value of the degree of polarization correction (Py), and the at least two regions have mutually different dichroic dye contents. The polarizing film 1 has a liquid crystal layer 11, but may further have a base layer 13, an alignment layer 12, other layers, and the like. Although the polarizing film 1 shown in FIG. 1 (b) shows an example in which the alignment layer 12 and the liquid crystal layer 11 are provided on one side of the base layer 13, the alignment layer and the liquid crystal layer are provided on both sides of the base layer 13. It may be done. The structures of the liquid crystal layers provided on both sides of the base layer 13 may be the same as or different from each other.

The polarizing film 1 may be an elongated polarizing film having a length of 10 m or more. In this case, the polarizing film 1 can be a wound body wound in a roll. The polarizing film can be continuously drawn out from the wound body and laminated with a retardation layer to be described later, or can be cut into pieces. Although the length of the elongate polarizing film used as a winding body will not be specifically limited if it is 10 m or more, For example, it can be 10000 m or less.

(Liquid crystal layer)
The liquid crystal layer 11 contains a liquid crystal compound and has a region containing the liquid crystal compound and a dichroic dye. When the polarizing film 1 has the polarization characteristic of the plane of the polarizing film 1, it is preferable to have a region in which the dichroic dye and the liquid crystal compound are horizontally aligned with respect to the plane of the polarizing film 1. When the polarizing film 1 has polarization characteristics in the film thickness direction of the polarizing film 1, it is preferable to have a region in which the dichroic dye and the liquid crystal compound are horizontally aligned with respect to the plane of the polarizing film 1.

The region of the liquid crystal layer 11 which contains a dichroic dye and a liquid crystal compound and is in a state in which the dichroic dye and the liquid crystal compound are horizontally aligned relative to one plane of the polarizing film is a liquid crystal alignment horizontal direction with respect to light of wavelength λ nm. It is preferable that the dichroic ratio (= A1 (λ) / A2 (λ)) which is the ratio of the absorbance A1 (λ) of the liquid crystal to the absorbance A2 (λ) in the vertical direction in the liquid crystal alignment plane is 7 or more. Is more preferably 30 or more. The higher the value, the better the polarization characteristics of the absorption selectivity. Depending on the type of dichroic dye, when the liquid crystal layer 11 is a nematic liquid crystal phase, the above ratio is about 5 to 10. When the liquid crystal layer 11 is a nematic liquid crystal phase and a smectic liquid crystal phase to be described later, the fact that the liquid crystal compound and the dichroic dye are not phase separated means, for example, surface observation with various microscopes or scattering degree measurement with a haze meter It can confirm by.

As shown in FIGS. 1 (a) and 1 (b), the liquid crystal layer 11 is distinguished by the degree of polarization correction (Py), and is distinguished by the content of the dichroic dye. It has two areas 11b. The polarizing film 1 shown in FIG. 1A shows an example in which each of two regions different in the visibility correction polarization degree (Py) and the content of the dichroic dye is one each. Two or more second regions may be present, and three or more regions in which the dichroic dye content is different from one another may be provided.

The first region 11 a of the polarizing film 1 shown in FIG. 1A contains a liquid crystal compound and a dichroic dye. The second region 11 b contains a liquid crystal compound, but may or may not contain a dichroic dye, and in the case of containing a dichroic dye, the content is the same as that contained in the first region 11 a. It is preferable that it is less than the content rate of the dichroic dye.

The content of the dichroic dye in the liquid crystal layer 11 can be determined, for example, by measuring the absorbance at the absorption maximum wavelength (λ _MAX ) of the dichroic dye.

The first area 11a is preferably an area having high polarization characteristics, and for example, the visibility correction polarization degree (Py) can be 90% or more, preferably 92% or more, and 95% or more. Is more preferable, and usually 100% or less. In addition, the first region 11a can have the visibility correction single transmittance (Ty) of, for example, 35% or more, preferably 40% or more, more preferably 44% or more, and usually 50%. Less than.

The second region 11 b is preferably a low polarization region having a visibility correction polarization degree (Py) lower than the visibility correction polarization degree (Py) of the first region 11 a. The visibility correction polarization degree (Py) of the second region 11 b can be, for example, 10% or less, preferably 5% or less, more preferably 1% or less, and even 0% Good. In addition, it is preferable that the second region 11 b has a visibility correction single transmittance (Ty) higher than the visibility correction single transmittance (Ty) of the first region 11 a. In the second region 11b, the visibility correction single transmittance (Ty) can be set to, for example, 80% or more, preferably 85% or more, more preferably 88% or more, and usually 98% or less. is there.

The visibility correction polarization degree (Py) and the visibility correction single transmittance (Ty) in the present specification can be calculated based on the degree of polarization and the single transmittance measured using a spectrophotometer. For example, the transmittance of the transmittance of the transmission axis direction in the wavelength range of 380 nm ~ 780 nm is visible light (alignment vertical) _{(T 1)} and the absorption axis direction (oriented the same direction) to _{(T 2),} the spectrophotometer It can measure by a double beam method using the apparatus which set the folder with a polarizer. For the degree of polarization and single transmittance in the visible light range, the degree of polarization and single transmittance at each wavelength are calculated using the following formulas (Formula 1) and (Formula 2) By performing the visibility correction with the light source), it is possible to calculate the visibility correction single transmittance (Ty) and the visibility correction polarization degree (Py).

Degree of polarization [%] = {(T ₁ −T ₂ ) / (T ₁ + T ₂ )} × 100 (Equation 1)
Single transmittance [%] = (T ₁ + T ₂ ) / 2 (equation 2)

The occupied area of the first area 11 a and the occupied area of the second area 11 b may be appropriately selected according to the characteristics required of the polarizing film 1. The ratio of the total occupied area of the first region 11a and the second region 11b to the surface area of the polarizing film 1 is preferably 90% or more, more preferably 95% or more, and 99% or more. Is more preferred. In addition, the occupied area of the first area 11a is preferably 50% or more, more preferably 70% or more, of the total area of the occupied area of the first area 11a and the occupied area of the second area 11b. Preferably, it is 80% or more. For example, as shown in FIG. 1A, the area occupied by the second area 11b is smaller than the area occupied by the first area 11a, and the first area 11a may be provided so as to surround the second area 11b. In the polarizing film 1 shown to Fig.1 (a), although 1st area | region 11a is provided so that one circular 2nd area | region 11b may be surrounded, two or more 2nd area | regions 11b may be provided independently, respectively.

The shape of the first area 11a and the shape of the second area 11b are not particularly limited. For example, as shown in FIG. 1A, when the first area 11a is provided to surround the second area 11b, the second area 11b can be formed into any shape such as a circular shape; an oval shape; a polygonal shape such as a triangle, a square, a rectangle, a rhombus, a letter shape, a combination thereof, and the like in a plan view shape.

The second region 11 b preferably has a circular, elliptical, oval or polygonal shape in plan view. When the second region 11 b is circular, the diameter is preferably 5 cm or less, more preferably 3 cm or less, and still more preferably 2 cm or less. When the second region 11 b is elliptical or oblong, the major axis is preferably 5 cm or less, more preferably 3 cm or less, and still more preferably 2 cm or less. When the second region 11b is a polygon, the diameter of the virtual circle drawn so as to be inscribed in this polygon is preferably 5 cm or less, more preferably 3 cm or less, and 2 cm or less Is more preferred. The second region 11 b having the above-described shape can be suitably used as a region corresponding to the lens position of a camera provided in a smartphone, a tablet, or the like. At this time, the second region 11b is a region where the visibility correction polarization degree (Py) is 10% or less and the visibility correction single transmittance (Ty) is 80% or more. The performance of the camera can be improved because the coloration of the image can be reduced, and excellent transparency can be obtained.

Furthermore, the first area 11a and the second area 11b may be provided such that the shape in plan view is linear, band-like, wave-like, or the like. In this case, a plurality of first areas 11a and a plurality of second areas 11b may be alternately provided. In this case, the widths of the first region 11a and the second region 11b are preferably independently 1 μm to 10 mm, more preferably 1 μm to 1 mm, and still more preferably 1 μm to 100 μm.

In the case where the polarizing film is a long polarizing film, the long polarizing film is usually cut into a predetermined size according to the application of the polarizing film, etc. It is preferable to set the arrangement of the first area 11a and the second area 11b in the elongated polarizing film so that the first area 11a and the second area 11b are formed. For example, in the case where the polarizing film after cutting is the polarizing film 1 shown in FIG. 1A, a plurality of second regions at predetermined intervals in the longitudinal direction and / or the width direction of the long polarizing film It is preferable to provide 11b.

The thickness of the first region 11a in the liquid crystal layer 11 is preferably 0.5 μm or more, more preferably 1 μm or more, and preferably 5 μm or less, more preferably 3 μm or less. The thickness of the second region 11b in the liquid crystal layer 11 is preferably the same as that of the first region 11a, preferably 0.5 μm or more, more preferably 1 μm or more, and 5 μm or less Is preferably, and more preferably 3 μm or less. The thickness of the liquid crystal layer 11 can be measured by an interference film thickness meter, a laser microscope, a stylus film thickness meter, or the like.

The thickness of the second area 11b may be smaller than the thickness of the first area 11a, but the difference between the thickness of the first area 11a and the thickness of the second area 11b is preferably 2 μm or less, and 1 μm or less And more preferably 0.5 μm or less. By making the thickness of the first region 11a and the second region 11b of the liquid crystal layer 11 approximately the same and reducing the difference between the first region 11a and the second region 11b, a retardation layer to be described later and the like are described later. When the layers (surface protective layer etc.) are laminated, defects such as biting of air bubbles and generation of wrinkles can be suppressed. Moreover, when the polarizing film 1 having the liquid crystal layer 11 is wound into a roll, it is possible to suppress a defect such as formation of a winding mark.

(Liquid crystal compound)
As a liquid crystal compound contained in the liquid crystal layer 11, a known liquid crystal compound can be used. The type of liquid crystal compound is not particularly limited, and rod-like liquid crystal compounds, discotic liquid crystal compounds, and mixtures thereof can be used. The liquid crystal compound may be a polymer liquid crystal compound, a polymerizable liquid crystal compound, or a mixture of these.

It is preferable to use a polymerizable liquid crystal compound as the liquid crystal compound. By using the polymerizable liquid crystal compound, the hue of the polarizing film can be arbitrarily controlled, and the thickness of the polarizing film can be significantly reduced. Moreover, since a polarizing film can be manufactured without performing an extending | stretching process, it can be set as the non-stretchable polarizing film without the extending | stretching relaxation by heat.

The polymerizable liquid crystal compound refers to a compound having a polymerizable group and having liquid crystallinity. The polymerizable group means a group involved in the polymerization reaction, and is preferably a photopolymerizable group. Here, the photopolymerizable group means a group capable of participating in the polymerization reaction by active radicals or acids generated from a photopolymerization initiator described later. Examples of the polymerizable group include vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloyloxy group, methacryloyloxy group, oxiranyl group, oxetanyl group and the like. Among them, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxiranyl group or an oxetanyl group is preferable, and an acryloyloxy group is more preferable. The liquid crystallinity may be a thermotropic liquid crystal or a lyotropic liquid crystal, but when mixed with a dichroic dye as in the liquid crystal layer of the present embodiment, it is preferable to use a thermotropic liquid crystal.

When the polymerizable liquid crystal compound is a thermotropic liquid crystal, it may be a thermotropic liquid crystal compound exhibiting a nematic liquid crystal phase or a thermotropic liquid crystal compound exhibiting a smectic liquid crystal phase. When the liquid crystal layer 11 exhibits a polarization function as a polymer film obtained by a polymerization reaction, the liquid crystal state exhibited by the polymerizable liquid crystal compound is preferably a smectic phase, and from the viewpoint of performance improvement, higher order smectic More preferably, it is a phase. Among them, higher-order smectic liquid crystal compounds forming a smectic B phase, a smectic D phase, a smectic E phase, a smectic F phase, a smectic G phase, a smectic H phase, a smectic I phase, a smectic J phase, a smectic K phase or a smectic L phase More preferred are higher order smectic liquid crystal compounds which form smectic B phase, smectic F phase or smectic I phase. When the liquid crystal layer 11 formed by the polymerizable liquid crystal compound is a high-order smectic phase, a region with higher polarization performance can be formed in the liquid crystal layer 11. In addition, regions with high polarization performance as described above are those in which Bragg peaks derived from higher order structures such as hexatic phase and crystal phase are obtained in X-ray diffraction measurement. The Bragg peak is a peak derived from the periodic structure of molecular orientation, and a film having a periodic spacing of 3 to 6 Å can be obtained. In the polarizing film 1 of the present embodiment, it is preferable that the liquid crystal layer 11 contains a polymer in which the polymerizable liquid crystal compound is polymerized in the smectic phase, for example, because the first region 11a can have higher polarization characteristics.

Whether or not the polymerizable liquid crystal compound exhibits a nematic liquid crystal phase or a smectic liquid crystal phase can be confirmed, for example, as follows. After the composition for forming a polarizing film is applied to a substrate to form a coated film, the solvent contained in the coated film is removed by heat treatment under the condition that the polymerizable liquid crystal compound is not polymerized. Subsequently, the coating film formed on the substrate is heated to an isotropic phase temperature, and the liquid crystal phase developed by gradually cooling is inspected by texture observation with a polarizing microscope, X-ray diffraction measurement or differential scanning calorimetry Do.

Specifically as such a polymerizable liquid crystal compound, the following formula (A)
U ¹ -V ¹ -W ¹ -X ¹ -Y ¹ -X ² -Y ² -X ³ -W ² -V ² -U ² (A)
[In the formula (A), X ¹ , X ² and X ³ each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group, and here, the divalent aromatic group Or a hydrogen atom contained in a divalent alicyclic hydrocarbon group is a halogen atom, an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a cyano group Or a nitro group may be substituted, and a carbon atom constituting the divalent aromatic group or divalent alicyclic hydrocarbon group may be substituted by an oxygen atom, a sulfur atom or a nitrogen atom . Provided that at least one of X ¹ , X ² and X ³ is a 1,4-phenylene group which may have a substituent or a cyclohexane-1,4-diyl group which may have a substituent It is.
Y ¹ , Y ² , W ¹ and W ² are each independently a single bond or a divalent linking group.
V ¹ and V ² each independently represent an alkanediyl group having 1 to 20 carbon atoms which may have a substituent, and -CH _2- constituting the alkanediyl group is -O-,- It may be replaced by S- or NH-.
U ¹ and U ² independently of one another represent a polymerizable group or a hydrogen atom, and at least one is a polymerizable group. ]
And the like (hereinafter sometimes referred to as compound (A)) and the like can be mentioned.

In the compound (A), at least one of X ¹ , X ² and X ³ is a 1,4-phenylene group which may have a substituent, or cyclohexane which may have a substituent It is a 1,4-diyl group. In particular, X ¹ and X ³ are preferably a cyclohexane-1,4-diyl group which may have a substituent, and the cyclohexane-1,4-diyl group is preferably a trans-cyclohexane-. More preferably, it is a 1,4-diyl group. When the structure of trans-cyclohexane-1,4-diyl group is included, smectic liquid crystallinity tends to be easily developed. Moreover, as a substituent which the 1,4-phenylene group which may have a substituent and the cyclohexane-1,4-diyl group which may have a substituent optionally have, a methyl group, ethyl Examples thereof include alkyl groups having 1 to 4 carbon atoms such as a group or a butyl group, halogen atoms such as a cyano group, a chlorine atom or a fluorine atom. Preferably it is unsubstituted.

Y ¹ and ^{Y 2,} independently of one another, a single _{_{_{bond, -CH 2 CH 2 -, -}}} CH 2 O -, - COO -, - OCO -, - N = N -, - CR a = CR b -, - C≡C— or CR ^a NN— is preferable, and R ^a and R ^b independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Y ¹ and Y ² are more preferably —CH ₂ CH ₂ —, —COO—, —OCO— or a single bond, and X ¹ , X ² and X ³ all contain a cyclohexane-1,4-diyl group. If not, it is more preferred that Y ¹ and Y ² be different bonding systems. In the case where Y ¹ and Y ² are bonding systems different from each other, smectic liquid crystallinity tends to be easily exhibited.

W ¹ and W ² are preferably, independently of one another, a single bond, —O—, —S—, —COO— or OCO—, and more preferably, independently of each other, be a single bond or —O—.

As the C 1-20 alkanediyl group represented by V ¹ and V ² , a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,3-diyl group, a butane-1,4 -Diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, decane-1,10-diyl group, tetradecane There may be mentioned -1,14-diyl or icosane-1,20-diyl and the like. V ¹ and V ² are preferably alkanediyl groups having 2 to 12 carbon atoms, and more preferably linear alkanediyl groups having 6 to 12 carbon atoms. By the linear alkanediyl group having 6 to 12 carbon atoms, the crystallinity is improved, and smectic liquid crystallinity tends to be easily exhibited.

Examples of the substituent optionally possessed by the optionally substituted alkanediyl group having 1 to 20 carbon atoms include a cyano group and a halogen atom such as a chlorine atom or a fluorine atom, and the alkanediyl group is It is preferably unsubstituted, and more preferably an unsubstituted and linear alkanediyl group.

Both U ¹ and U ² are preferably polymerizable groups, and both are more preferably photopolymerizable groups. A polymerizable liquid crystal compound having a photopolymerizable group can be polymerized under a lower temperature condition than a thermally polymerizable group, and is thus advantageous in that a polymer of the polymerizable liquid crystal compound can be formed in a highly ordered state.

The polymerizable groups represented by U ¹ and U ² may be different from each other, but are preferably the same. Examples of the polymerizable group include vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloyloxy group, methacryloyloxy group, oxiranyl group, oxetanyl group and the like. Among them, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxiranyl group or an oxetanyl group is preferable, and a methacryloyloxy group or an acryloyloxy group is more preferable.

Examples of such a polymerizable liquid crystal compound include the following.

Among the exemplified compounds, Formula (1-2), Formula (1-3), Formula (1-4), Formula (1-6), Formula (1-7), Formula (1-8), Formula At least one selected from the group consisting of compounds represented by (1-13), formula (1-14) and formula (1-15) is preferable.

The exemplified compounds (A) can be used for the liquid crystal layer 11 alone or in combination. When two or more polymerizable liquid crystal compounds are combined, it is preferable that at least one be a compound (A), and it is more preferable that two or more be a compound (A). By combining two or more polymerizable liquid crystal compounds, it may be possible to temporarily maintain liquid crystallinity even at a temperature below the liquid crystal-crystal phase transition temperature. The mixing ratio when combining two kinds of polymerizable liquid crystal compounds is usually 1:99 to 50:50, preferably 5:95 to 50:50, and 10:90 to 50:50. Is more preferred.

The compound (A) is described, for example, in Lub et al. Recl. Trav. Chim. It can manufacture by the well-known method as described in Pays-Bas, 115, 321-328 (1996) or patent 4719156 grade | etc.,.

The content of the polymerizable liquid crystal compound in the liquid crystal layer 11 is usually 50 to 99.5 parts by mass, preferably 60 to 99 parts by mass, relative to 100 parts by mass of the solid content of the liquid crystal layer 11. Is 70 to 98 parts by mass, more preferably 80 to 97 parts by mass. If the content of the polymerizable liquid crystal compound is in the above range, the orientation tends to be high. Here, solid content means the thing of the total amount of the component except the solvent from the composition for polarizing layer formation mentioned later.

(Dichroic dye)
The dichroic dye is a dye having a property in which the absorbance in the long axis direction of the molecule and the absorbance in the short axis direction are different. The dichroic dye is a dye that is oriented with the liquid crystal compound to exhibit dichroism, and the dichroic dye itself may have polymerizability or liquid crystallinity. The dichroic dye preferably has a property of absorbing visible light, and more preferably one having an absorption maximum wavelength (λ _MAX ) in the range of 380 to 680 nm. As such a dichroic dye, for example, an acridine dye, an oxazine dye, a cyanine dye, a naphthalene dye, an azo dye, an anthraquinone dye and the like can be mentioned, and among them, an azo dye is preferable. Examples of the azo dye include monoazo dyes, bisazo dyes, trisazo dyes, tetrakisazo dyes, stilbene azo dyes and the like, with preference given to bisazo dyes or trisazo dyes. The dichroic dyes may be used alone or in combination of two or more types, but in order to obtain absorption in the entire visible light range, it is preferable to combine three or more types of dichroic dyes, It is more preferable to combine a kind or more of azo dyes.

As an azo dye, for example, a compound of the formula (I)
T ¹ -A ¹ (-N = N-A ² ) _p -N = N-A ³ -T ² (I)
[In the formula (I), A ¹ , A ² and A ³ are each independently a 1,4-phenylene group which may have a substituent, a naphthalene-1,4-diyl group, or a substituent And T ¹ and T ² independently of each other are an electron withdrawing group or an electron emitting group, and the position is substantially 180 ° with respect to the azo bonding surface. Have to. p represents an integer of 0 to 4; When p is 2 or more, each A ² may be the same or different. The -N = N- bond may be replaced by -C = C-, -COO-, -NHCO- or -N = CH- bond within the range showing absorption in the visible region. ]
And a compound represented by (hereinafter sometimes referred to as "compound (I)").

As a substituent which the 1,4-phenylene group, the naphthalene-1,4-diyl group and the divalent heterocyclic group in A ¹ , A ² and A ³ optionally have, such as methyl group, ethyl group or butyl group An alkyl group having 1 to 4 carbon atoms; an alkoxy group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group or a butoxy group; a fluorinated alkyl group having 1 to 4 carbon atoms such as a trifluoromethyl group; a cyano group; Halogen atoms such as chlorine atom and fluorine atom; substituted or unsubstituted amino groups such as amino group, diethylamino group and pyrrolidino group (amino group having one or two alkyl groups having 1 to 6 carbon atoms) group, or two of the substituted alkyl group is meant bonded to the amino group which forms an alkanediyl group having 2 to 8 carbon atoms with each other. unsubstituted amino group is -NH _2.) can be mentioned . Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group and a hexyl group. Examples of the alkanediyl group having 2 to 8 carbon atoms include ethylene group, propane-1,3-diyl group, butane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group. And hexane-1,6-diyl group, heptane-1,7-diyl group, and octane-1,8-diyl group. In order to include the compound (I) in a highly ordered liquid crystal structure such as a smectic liquid crystal, A ¹ , A ² and A ³ are each independently unsubstituted, and hydrogen is substituted with a methyl group or a methoxy group A 1,4-phenylene group or a divalent heterocyclic group is preferable, and p is preferably 0 or 1. Among them, p is 1 and at least two of the three structures of A ¹ , A ² and A ³ are 1,4-phenylene groups, in that they have both simplicity of molecular synthesis and high performance. More preferable.

Examples of the divalent heterocyclic group include quinoline, thiazole, benzothiazole, thienothiazole, imidazole, benzimidazole, oxazole and a group in which two hydrogen atoms are removed from benzoxazole. When A ² is a divalent heterocyclic group, a structure having a molecular bonding angle of substantially 180 ° is preferable, and specifically, benzothiazole, benzimidazole, benzoxazole in which two 5-membered rings are condensed. The structure is more preferred.

T ¹ and T ² are, independently of each other, an electron withdrawing group or an electron emitting group, which are preferably different from each other, and T ¹ is an electron withdrawing group and T ² is an electron emitting group, or More preferably, T ¹ is an electron-emitting group and T ² is an electron-withdrawing group. Specifically, T ¹ and T ² independently represent an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, a nitro group, or an alkyl group having 1 to 6 carbon atoms. Or an amino group having two or two substituted alkyl groups bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms, or a trifluoromethyl group, preferably a smectic liquid crystal. In order to be included in such a highly ordered liquid crystal structure, it is necessary to have a structure with a smaller excluded volume of the molecule, so an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group An amino group having one or two alkyl groups having 1 to 6 carbon atoms, or an amino group in which two substituted alkyl groups are bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms is preferable.

Examples of such azo dyes include the following.

In formulas (2-1) to (2-6), B ¹ to B ²⁰ independently of each other represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, It represents a nitro group, a substituted or unsubstituted amino group (as defined for the substituted amino group and the unsubstituted amino group as described above), a chlorine atom or a trifluoromethyl group. Further, from the viewpoint of obtaining high polarization performance, B ² , B ⁶ , B ⁹ , B ¹⁴ , B ¹⁸ and B ¹⁹ are preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.
n1 to n4 each independently represent an integer of 0 to 3.
When n1 is 2 or more, a plurality of B ² may be identical to or different from each other,
When n2 is 2 or more, a plurality of B ⁶ may be identical to or different from each other,
When n3 is 2 or more, a plurality of B ⁹ may be identical to or different from each other,
When n4 is 2 or more, the plurality of B ¹⁴ may be identical to or different from each other.

As the anthraquinone dye, a compound represented by Formula (2-7) is preferable.

[In Formula (2-7), R ¹ to R ⁸ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom.
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

The oxazine dye is preferably a compound represented by the formula (2-8).

[In the formula (2-8), R ⁹ to R ¹⁵ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom. ]
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

The acridine dye is preferably a compound represented by formula (2-9).

[In the formula (2-9), R ¹⁶ to R ²³ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom.
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

Examples of the alkyl group having 1 to 4 carbon atoms represented by ^Rx in formulas (2-7), (2-8) and (2-9) include a methyl group, an ethyl group, a propyl group and a butyl group And a pentyl group or a hexyl group. Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, a toluyl group, a xylyl group or a naphthyl group.

The cyanine dye is preferably a compound represented by Formula (2-10) and a compound represented by Formula (2-11).

[In Formula (2-10), D ¹ and D ² independently represent a group represented by any one of Formula (2-10a) to Formula (2-10d).

n5 represents an integer of 1 to 3; ]

[In the formula (2-11), D ³ and D ⁴ each independently represent a group represented by any one of the formulas (2-11 a) to (2-11 h).

n6 represents an integer of 1 to 3; ]

As in the case of the first region 11 a of the liquid crystal layer 11, the content of the dichroic dye (the ratio of the total amount thereof in the case of containing plural kinds) is, like the first region 11 a of the liquid crystal layer 11, In a region having a high polarization property of 90% or more of Py), it is usually preferably 0.1 to 30 parts by mass, and more preferably 1 to 20 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. Preferably, it is 3 to 15 parts by mass. When the content of the dichroic dye is less than this range, light absorption is insufficient, sufficient polarization performance can not be obtained, and when it is more than this range, the alignment of liquid crystal molecules may be inhibited. As in the second region 11b of the liquid crystal layer 11, in a region where the polarization characteristic with a visibility correction polarization degree (Py) of 10% or less is low, usually 0 to 20 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. The content is preferably 0 to 10 parts by mass, more preferably 0 to 5 parts by mass.

(Base material layer)
The polarizing film 1 may have a base layer 13. The base material layer 13 can be used, for example, to support the alignment layer 12 and the polarizing layer 21 described later when producing the polarizing film 1 as described later, and the liquid crystal layer 11 of the polarizing film 1 can be used. It can be used to support.

The base material layer 13 may be a glass base material or a resin base material, but is preferably a resin base material. Moreover, from the point which can manufacture the polarizing film 1 continuously, it is more preferable that the base material layer 13 unrolls the elongate resin base material wound by roll shape. The resin substrate is preferably a light-transmissive substrate capable of transmitting visible light. Here, the term “transparency” means that the transmittance of a single visible sensitivity correction is 80% or more for light in a wavelength range of 380 to 780 nm.

The thickness of the base material layer 13 is preferably thin in that it is a mass that can be practically handled, but if it is too thin, the strength tends to decrease and the processability tends to be poor. The thickness of the base layer 13 is usually 5 μm to 300 μm, preferably 20 μm to 200 μm. The base material layer 13 may be provided so as to be peelable. For example, after bonding the liquid crystal layer 11 of the polarizing film 1 to a member forming a display device, a retardation layer to be described later, etc. It may be removable from the Thereby, the further film thinning effect of the polarizing film 1 is acquired.

Examples of the resin constituting the resin base include polyolefins such as polyethylene and polypropylene; cyclic olefin resins such as norbornene polymers; polyvinyl alcohol; polyethylene terephthalate; polymethacrylic acid esters; polyacrylic acid esters; Cellulose esters such as cellulose and cellulose acetate propionate; polyethylene naphthalate; polycarbonate; polysulfone; polyethersulfone; polyethersulfone; polyether ketone; polyphenylene sulfide and polyphenylene oxide;

Examples of commercially available resin base materials of cellulose ester include “Fujitack film” (manufactured by Fuji Photo Film Co., Ltd.); “KC8UX2M”, “KC8UY” and “KC4UY” (all manufactured by Konica Minolta Opto Co., Ltd.), etc. .

Examples of commercially available cyclic olefin resins include “Topas” (registered trademark) (manufactured by Ticona, Germany), “Arton” (registered trademark) (manufactured by JSR Corporation), “ZEONOR” (registered trademark), Examples include "ZEONEX" (registered trademark) (manufactured by Nippon Zeon Co., Ltd.) and "APEL" (registered trademark) (manufactured by Mitsui Chemicals, Inc.). Such a cyclic olefin resin can be formed into a film by a known means such as a solvent casting method and a melt extrusion method to make a resin substrate. The resin base material of cyclic olefin resin marketed can also be used. As resin base materials of commercially available cyclic olefin-based resins, "ESSINA" (registered trademark), "SCA 40" (registered trademark) (above, manufactured by Sekisui Chemical Co., Ltd.), "Zeonor Film" (registered trademark) (OPTES share) And “Arton Film” (registered trademark) (manufactured by JSR Corporation).

The base material layer 13 may have a single layer structure or a multilayer structure of two or more layers. When the base material layer 13 is a multilayer structure, each layer may be formed of the same material, or may be formed of different materials.

Moreover, the base material layer 13 may have a 1⁄4 wavelength plate function. When the base material layer 13 has a 1⁄4 wavelength plate function, a combination of the base material layer 13 and the liquid crystal layer 11 can provide a polarizing film having the function of a circularly polarizing plate. Thereby, a circularly-polarizing plate can be obtained even if it does not bond the retardation film which has a 1⁄4 wavelength plate function separately from the base material layer 13 to the polarizing film 1. When the base material layer 13 has a multilayer structure, the liquid crystal layer 11 may be a half-wave plate using a laminate of a layer having the half-wave plate function and a layer having the quarter-wave plate function. A circularly-polarizing plate can be obtained by laminating | stacking on the layer side which has a function. Alternatively, in the case where the base material layer 13 has a multilayer structure, a circularly polarizing plate can also be used by using a layer in which a layer having inverse wavelength dispersive 1/4 wavelength plate function and a layer having positive C plate function are laminated. You can get

(Alignment layer)
The polarizing film 1 may have an alignment layer 12 on the base material layer 13, and the alignment layer 12 is disposed between the base material layer 13 and the liquid crystal layer 11. The alignment layer 12 can have an alignment regulating force that causes the liquid crystal compound in the liquid crystal layer 11 stacked thereon to be aligned in a desired direction.

The alignment layer 12 facilitates the liquid crystal alignment of the liquid crystal compound. The state of liquid crystal alignment such as horizontal alignment, vertical alignment, hybrid alignment, and tilt alignment changes depending on the properties of the alignment layer 12 and the liquid crystal compound, and the combination thereof can be arbitrarily selected. For example, if the alignment layer 12 is a material that expresses horizontal alignment as alignment regulating force, the liquid crystal compound can form horizontal alignment or hybrid alignment, and if the alignment layer 12 is a material that expresses vertical alignment, liquid crystal The compounds can form a vertical orientation or a tilted orientation. The expressions such as horizontal and vertical represent the direction of the major axis of the aligned liquid crystal compound when the plane of the polarizing film 1 is used as a reference. For example, the vertical alignment is to have the major axis of the aligned polymerizable liquid crystal in the direction perpendicular to the plane of the polarizing film 1. As used herein, perpendicular means 90 ° ± 20 ° with respect to the plane of the polarizing film 1. Since it is preferable that the polarizing film 1 has the polarization | polarized-light characteristic of the polarizing film 1 flat surface, it is preferable to form the orientation layer 12 using the material which expresses horizontal orientation.

When the alignment layer 12 is formed of an alignment polymer, the alignment regulating force of the alignment layer 12 can be arbitrarily adjusted according to the surface state and the rubbing conditions, and is formed of a photoalignment polymer. Can be adjusted arbitrarily according to polarized light irradiation conditions and the like. The liquid crystal alignment can also be controlled by selecting physical properties such as surface tension and liquid crystallinity of the polymerizable liquid crystal compound.

The thickness of the alignment layer 12 is usually 10 nm to 5000 nm, preferably 10 nm to 1000 nm, and more preferably 30 nm to 300 nm. In addition, the alignment layer 12 formed between the base material layer 13 and the liquid crystal layer 11 is insoluble in the solvent used when forming the liquid crystal layer 11 on the alignment layer 12, and the removal of the solvent and the like It is preferable to have heat resistance in heat treatment for alignment of liquid crystal.

Examples of the alignment layer 12 include an alignment film made of an alignment polymer, a photo alignment film, a groove alignment film, and the like. In the case where the base material layer 13 is unrolled from a roll-shaped long resin base material, the alignment layer 12 is preferably a photoalignment film from the viewpoint of easily controlling the alignment direction.

Examples of orientation polymers include polyamides and gelatins having an amide bond in the molecule, polyimides having an imide bond in the molecule, polyamic acid which is a hydrolyzate thereof, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyoxazole, Examples thereof include polyethylene imine, polystyrene, polyvinyl pyrrolidone, polyacrylic acid, and polyacrylic acid esters. Among them, polyvinyl alcohol is preferred. These orientable polymers may be used alone or in combination of two or more.

In an alignment film made of an alignment polymer, a composition in which the alignment polymer is dissolved in a solvent (hereinafter sometimes referred to as “alignment polymer composition”) is applied to the substrate layer 13 to remove the solvent. Alternatively, it can be obtained by applying the oriented polymer composition to the substrate layer 13, removing the solvent, and rubbing (rubbing method).

Examples of the solvent used for the orientable polymer composition include water; alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, methyl cellosolve, butyl cellosolve or propylene glycol monomethyl ether; ethyl acetate, butyl acetate, ethylene glycol methyl Ester solvents such as ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate or ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, methyl amyl ketone or methyl isobutyl ketone; fats such as pentane, hexane or heptane Group hydrocarbon solvents; aromatic hydrocarbon solvents such as toluene or xylene; nitrile solvents such as acetonitrile; Rofuran or ether solvents such as dimethoxyethane; chloroform or chlorinated hydrocarbon solvents such as chlorobenzene; and the like. These solvents may be used alone or in combination of two or more.

The content of the orienting polymer in the orientating polymer composition may be in the range in which the orienting polymer can be completely dissolved in the solvent, but is preferably 0.1 to 20% by mass in terms of solid content with respect to the solution. 0.1 to 10% by mass is more preferable.

A commercially available alignment film material may be used as it is as an alignment polymer composition. Examples of commercially available alignment film materials include Sun Ever (registered trademark) (manufactured by Nissan Chemical Industries, Ltd.) or Optomer (registered trademark) (manufactured by JSR Corporation).

As a method of applying the oriented polymer composition to the substrate layer 13, coating methods such as spin coating method, extrusion method, gravure coating method, die coating method, bar coating method or applicator method, flexo method, etc. There are known methods such as the printing method. When the polarizing film 1 is produced by a roll-to-roll type continuous production method, a printing method such as a gravure coating method, a die coating method or a flexo method can be usually employed as the coating method.

By removing the solvent contained in the orientable polymer composition, a dry film of the orientable polymer is formed. As a method of removing the solvent, a natural drying method, a ventilation drying method, a heat drying method, a reduced pressure drying method and the like can be mentioned. Thereafter, the dried film can be brought into contact with a rotating rubbing roll on which a rubbing cloth is wound to form the alignment layer 12.

The photo alignment film is usually coated on the substrate layer 13 with a composition containing a polymer or monomer having a photo reactive group and a solvent (hereinafter sometimes referred to as “a composition for forming a photo alignment film”). It can obtain by irradiating polarized light (preferably polarized UV) to the coating layer for alignment layers formed. The photo alignment film is more preferable in that the direction of the alignment control force can be arbitrarily controlled by selecting the polarization direction of the polarized light to be irradiated.

The photoreactive group refers to a group that generates liquid crystal alignment ability by irradiating light. Specifically, it generates a light reaction that is the source of liquid crystal alignment ability, such as alignment induction or isomerization reaction of molecules generated by light irradiation, dimerization reaction, photocrosslinking reaction, or photolysis reaction. is there. Among the photoreactive groups, those capable of causing a dimerization reaction or a photocrosslinking reaction are preferable in that they are excellent in orientation. The photoreactive group capable of causing the above reaction is preferably one having an unsaturated bond, particularly a double bond, preferably a carbon-carbon double bond (CCC bond), a carbon-nitrogen double bond (C A group having at least one selected from the group consisting of NN bond), nitrogen-nitrogen double bond (N = N bond), and carbon-oxygen double bond (C = O bond) is more preferable.

Examples of the photoreactive group having a C = C bond include a vinyl group, a polyene group, a stilbene group, a stilbazole group, a stilbazolium group, a chalcone group or a cinnamoyl group. From the viewpoint of easy control of reactivity and from the viewpoint of expression of alignment control force at the time of light alignment, a chalcone group or a cinnamoyl group is preferable. Examples of photoreactive groups having a C = N bond include groups having a structure such as aromatic Schiff base or aromatic hydrazone. Examples of the photoreactive group having an N = N bond include an azobenzene group, an azonaphthalene group, an aromatic heterocyclic azo group, a bisazo group or a formazan group, and a group having an azoxybenzene as a basic structure. Examples of the photoreactive group having a C = O bond include benzophenone group, coumarin group, anthraquinone group, maleimide group and the like. These groups may have a substituent such as an alkyl group, an alkoxy group, an aryl group, an allyloxy group, a cyano group, an alkoxycarbonyl group, a hydroxyl group, a sulfonic acid group or a halogenated alkyl group.

As a solvent of the composition for forming a photo alignment film, those capable of dissolving a polymer having a photo reactive group and a monomer are preferable. As the solvent, for example, the solvents mentioned as the solvent of the alignment polymer composition described above, etc. Can be mentioned.

The content of the polymer or monomer having a photoreactive group in the composition for forming a photoalignment film is appropriately adjusted depending on the type of the polymer or monomer having a photoreactive group and the thickness of the photoalignment film to be produced. Although it is possible, 0.2 mass% or more is preferable, and a range of 0.3 to 10 mass% is particularly preferable. In addition, a polymer material such as polyvinyl alcohol or polyimide and a photosensitizer may be contained within the range that the characteristics of the photo alignment film are not significantly impaired.

As a method of applying the composition for photo alignment film formation to the base material layer 13, the method similar to the method of applying the above-mentioned orientation polymer composition to the base material layer 13 is mentioned. As a method of removing a solvent from the composition for photo-alignment film formation applied, the same method as the method of removing a solvent from alignment polymer composition is mentioned, for example.

The polarized light irradiation may be performed directly from above the dried film obtained by removing the solvent from the composition for forming a light alignment film coated on the base material layer 13, and the polarized light transmitted through the base material layer 13 irradiates the dried film. You may carry out from the base material layer 13 side so that it may be carried out. In addition, it is particularly preferable that polarized light used for polarized light irradiation is substantially parallel light. The wavelength of the polarized light to be irradiated is preferably in the wavelength range in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb light energy. Specifically, UV (ultraviolet light) having a wavelength of 250 to 400 nm is particularly preferable. Examples of light sources used for polarized light irradiation include xenon lamps, high pressure mercury lamps, ultra high pressure mercury lamps, metal halide lamps, ultraviolet light lasers such as KrF and ArF, etc., and high pressure mercury lamps, ultra high pressure mercury lamps or metal halide lamps are more preferable. . These lamps are preferable because the emission intensity of ultraviolet light with a wavelength of 313 nm is large. Polarized light can be illuminated by illuminating the light from the light source through a suitable polarizer. As such a polarizer, a polarizing filter, a polarizing prism such as Glan-Thomson, Glan-Taylor, or a wire grid type polarizer can be used.

A plurality of regions (patterns) having different liquid crystal alignment directions can also be formed by performing masking when performing rubbing or polarized light irradiation.

The groove alignment film is a film having a concavo-convex pattern or a plurality of grooves (grooves) on the film surface. When liquid crystal molecules are placed on a film having a plurality of straight grooves aligned at equal intervals, the liquid crystal molecules are aligned in the direction along the groove.

As a method of obtaining a globular alignment film, a method of forming a concavo-convex pattern by performing development and rinsing after exposure through an exposure mask having slits of a pattern shape on the surface of a photosensitive polyimide film, a plate having grooves on the surface Method of forming a layer of a UV curable resin before curing on a sheet-like master, transferring the resin layer to a substrate and then curing, a plurality of films of the UV curable resin before curing formed on a substrate, The roll-shaped original disc which has a groove | channel is pressed, an unevenness | corrugation is formed, and the method etc. which harden | cure are mentioned. Specifically, the methods described in JP-A-6-34976 and JP-A-2011-242743 can be mentioned.

In order to obtain an alignment with a small alignment disorder, the width of the convex portion of the glue alignment film is preferably 0.05 μm to 5 μm, and the width of the concave portion is preferably 0.1 μm to 5 μm. The depth is preferably 2 μm or less, and more preferably 0.01 μm to 1 μm or less.

(Other layers)
The polarizing film 1 may have layers other than the base material layer 13 and the alignment layer 12. For example, a surface protection layer for the purpose of protecting the surface of the liquid crystal layer 11 may be provided on the surface of the liquid crystal layer 11 opposite to the base material layer 13. Moreover, when peeling and using the base material layer 13, you may provide a surface protective layer in the surface at the side which peeled the base material layer 13 of the liquid-crystal layer 11. As shown in FIG. The surface protective layer may have a single layer structure or a multilayer structure. When the surface protective layer has a multilayer structure, each layer may be formed of the same material, or may be formed of different materials.

<Circularly polarizing plate>
2 (a) to 2 (c) are each a schematic cross-sectional view showing an example of the circularly polarizing plate of the present invention. The polarizing film 1 shown in FIG. 1 (b) is made to be circularly

polarizing plates

5a and 5b shown in FIGS. 2 (a) and 2 (b) by laminating a retardation layer 15 having a 1⁄4 wavelength plate function. Can. The retardation layer 15 may be laminated on the liquid crystal layer 11 side of the polarizing film 1 (FIG. 2 (a)) or may be laminated on the base material layer 13 side (FIG. 2 (b)). Moreover, what peeled the base material layer 13 from the circularly-polarizing plate 5a shown to Fig.2 (a) can also be used as a circularly-polarizing plate 5c (FIG.2 (c)), In this case, it aligns with the base material layer 13. The layer 12 may also be peeled off.

In addition, the circularly polarizing plate may be one in which the polarizing film 1 and a retardation layer having a multilayer structure are laminated. In this case, as the retardation layer of the multilayer structure, a retardation layer in which a layer having a half wave plate function and a layer having a quarter wave plate function can be laminated can be used. By laminating the layer side having the half wavelength plate function and the polarizing film 1, a circularly polarizing plate can be obtained. Alternatively, a circularly polarizing plate can also be obtained by using a retardation layer in which a layer having a function of a quarter wavelength plate with reverse wavelength dispersion and a layer having a positive C plate function are laminated as a retardation layer having a multilayer structure. be able to.

In addition, as the base material layer 13 of the polarizing film 1, one having a function as a retardation layer may be used, and a retardation layer may be further laminated to form a circularly polarizing plate. In this case, the function as the retardation layer of the base material layer 13 and the retardation layer may be selected according to the lamination position of the base material layer 13 and the retardation layer in the circularly polarizing plate.

The polarizing film and the retardation layer can be laminated via an adhesive layer using a known pressure-sensitive adhesive or adhesive.

<Method of Producing Polarizing Film (First Production Method)>
3 (a) to 3 (d) are schematic cross-sectional views showing the layer structure obtained in each step of the manufacturing process of the polarizing film 1 shown in FIG. 1 (b). The first production method of the polarizing film 1 is
Preparing a laminated film 62 (FIG. 3B) having a polarizing layer 21 containing a liquid crystal compound and a dichroic dye on at least one side of a substrate layer 13;
By contacting a partial region of the polarizing layer 21 of the laminated film 62 with a liquid capable of reducing the content of the dichroic dye in the polarizing layer 21, the dichroic dye in a partial region of the polarizing layer 21 is obtained. And a liquid contacting step of reducing the content of

In the liquid contact process, a protective layer 35 having a coated area 35 a for covering the polarizing layer 21 and an exposed area 35 b for exposing the polarizing layer 21 is laminated on the polarizing layer 21 of the laminated film 62. A protective layer laminating step of obtaining a laminated film 63 with protective layer (FIG. 3 (c));
By bringing the laminated film 63 with a protective layer into contact with a liquid capable of reducing the content of the dichroic dye in the polarizing layer 21, the content of the dichroic dye is reduced in a partial region of the polarizing layer 21. A decolorizing step of obtaining a colored decolorized laminated film 64 (FIG. 3 (d));
It has a peeling process which peels the protective layer 35 from this decolorized laminated film 64, and, thereby, the polarizing film 1 shown in FIG.1 (b) can be manufactured.

(Preparation process)
The laminated film 62 prepared in the preparation step is not particularly limited as long as it has the polarizing layer 21 on at least one side of the base layer 13, but as shown in FIG. 3 (b), it is oriented on the base layer 13. It is preferable that the layer 12 and the polarizing layer 21 be laminated in this order. Such a laminated film 62 is obtained by applying the composition for forming an alignment layer on one surface of the base material layer 13 to form an alignment layer 12 and forming a base material layer 61 with an alignment layer (FIG. 3A). And a polarizing layer forming step of forming a polarizing layer 21 by applying a composition for forming a polarizing layer on the side of the base layer 61 with an alignment layer on which the alignment layer 12 is formed. It can be manufactured through.

In the alignment layer forming step, the substrate layer 13 may be subjected to surface treatment before applying the composition for forming an alignment layer. As a method of surface treatment, for example, corona treatment, plasma treatment, laser treatment, ozone treatment, saponification treatment, flame treatment, coating treatment of coupling agent, primer treatment and the like can be mentioned. As the composition for forming an alignment layer, the above-described alignment polymer composition, a composition for forming a photo alignment film, a composition containing a resin material for forming a glue alignment film, and the like can be used. The method of forming the alignment layer using each composition is also as described above. For example, in the case where the composition for forming an alignment layer contains a photoalignable polymer, in the alignment layer forming step, the coating layer for an alignment layer formed by applying the composition for forming an alignment layer is irradiated with polarized light. An alignment layer having an alignment control force in a predetermined direction can be formed.

The composition for forming a polarizing layer is a composition containing a liquid crystal compound and a dichroic dye, and preferably contains a solvent and a polymerization initiator, and a sensitizer, a polymerization inhibitor, a leveling agent, a reactive additive, etc. May be included. As the liquid crystal compound and the dichroic dye, those described above can be used, and as the solvent, the polymerization initiator, the sensitizer, the polymerization inhibitor, the leveling agent, and the reactive additive, those described later can be used. .

As a method of applying the composition for forming a polarizing layer, extrusion coating method, direct gravure coating method, reverse gravure coating method, CAP coating method, slit coating method, microgravure method, die coating method, ink jet method, etc. may be mentioned. . Moreover, the method etc. of coating using coaters, such as a dip coater, a bar coater, a spin coater, etc. are mentioned. Among them, the coating method by microgravure method, ink jet method, slit coating method, die coating method is preferable in the case of continuous coating in the Roll to Roll format, and in the case of coating on a sheet substrate such as glass A highly uniform spin coating method is preferred. When coating is performed by a roll to roll method, a composition for forming an alignment film or the like is coated on the base material layer 13 to form an alignment layer 12, and a composition for forming a polarizing layer is further formed on the obtained alignment layer 12. It can also be applied continuously.

When coating the composition for polarizing layer formation and forming the polarizing layer 21, a solvent is removed from the coated polarizing layer formation composition, and the coating layer for polarizing layers is formed. As the method of removing the solvent, the same method as the method of removing the solvent from the oriented polymer composition can be used, and for example, natural drying, air drying, heat drying, reduced pressure drying and a combination thereof are mentioned. Be Among these, natural drying or heat drying is preferred. The drying temperature is preferably in the range of 0 to 200 ° C., more preferably in the range of 20 to 150 ° C., and still more preferably in the range of 50 to 130 ° C. The drying time is preferably 10 seconds to 10 minutes, more preferably 30 seconds to 5 minutes.

When the liquid crystal compound contained in the composition for forming a polarizing layer is a polymerizable liquid crystal compound, the coating layer for a polarizing layer formed in the step for forming a polarizing layer is irradiated with active energy rays to photopolymerize the polymerizable liquid crystal compound. Preferably, the polarizing layer 21 is formed as a polymer layer of the polymerizable liquid crystal compound. In the case of containing the type of the polymerizable liquid crystal compound (particularly, the type of the photopolymerizable functional group possessed by the polymerizable liquid crystal compound) and the photopolymerization initiator contained as the active energy ray to be irradiated, It is suitably selected according to the kind of photoinitiator and those quantities. Specifically, one or more types of light selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays, and γ-rays can be mentioned. Among them, ultraviolet light is preferable in that it is easy to control the progress of the polymerization reaction, and in that it can be used widely as an apparatus for photopolymerization, polymerization is possible so that it can be photopolymerized by ultraviolet light. It is preferable to select the type of the liquid crystal compound.

As a light source of active energy ray, for example, low pressure mercury lamp, medium pressure mercury lamp, high pressure mercury lamp, super high pressure mercury lamp, xenon lamp, halogen lamp, carbon arc lamp, tungsten lamp, gallium lamp, excimer laser, wavelength range 380 Examples thereof include an LED light source emitting ~ 440 nm, a chemical lamp, a black light lamp, a microwave excitation mercury lamp, a metal halide lamp and the like.

Irradiation intensity of the active energy rays are ^{usually, 10mW / cm 2 ~ 3000mW /} cm 2. The irradiation intensity of the active energy ray is preferably an intensity in a wavelength range effective for activating the cationic polymerization initiator or the radical polymerization initiator. The irradiation time of the active energy ray is usually 0.1 seconds to 10 minutes, preferably 0.1 seconds to 5 minutes, more preferably 0.1 seconds to 3 minutes, still more preferably 0. 1 second to 1 minute. When such irradiation once or several times with the irradiation intensity of the active energy ray, the cumulative amount of light ^{is, 10mJ / cm 2 ~ 3000mJ /} cm 2, preferably ^{50mJ / cm 2 ~ 2,000mJ / cm} 2, more preferably It can be 100 mJ / cm ² to 1000 mJ / cm ² . When the integrated light amount is less than this range, the curing of the polymerizable liquid crystal compound may be insufficient, and good transferability may not be obtained. On the contrary, when the integrated light amount is above this range, the polarizing layer may be colored.

(solvent)
The composition for forming a polarizing layer may contain a solvent. Generally, since the polymerizable liquid crystal compound has a high viscosity, when the polymerizable liquid crystal compound is used as the liquid crystal compound, coating is facilitated by using a composition for forming a polarizing layer containing a solvent, and as a result, a polarizing layer is formed. It will be easier. The solvent is preferably one that can completely dissolve the polymerizable liquid crystal compound and the dichroic dye, and is preferably a solvent inert to the polymerization reaction of the polymerizable liquid crystal compound.

As the solvent, alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether or propylene glycol monomethyl ether; ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone Or ester solvents such as propylene glycol methyl ether acetate or ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone or methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane or heptane; toluene Or an aromatic hydrocarbon solvent such as xylene, a nitrile solvent such as acetonitrile; Ether solvents such as dimethoxyethane or dimethoxyethane; chlorine-containing solvents such as chloroform or chlorobenzene; amide solvents such as dimethylacetamide, dimethylformiamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone Etc. These solvents may be used alone or in combination of two or more.

The content of the solvent contained in the composition for forming a polarizing layer is preferably 50 to 98% by mass with respect to the total amount of the composition for forming a polarizing layer. In other words, the content of solid content in the composition for forming a polarizing layer is preferably 2 to 50% by mass. When the content of the solid content is 50% by mass or less, the viscosity of the composition for forming a polarizing layer is low, so that the thickness of the polarizing layer 21 becomes substantially uniform, and unevenness tends not to occur in the polarizing layer 21. There is. The solid content can be determined in consideration of the thickness of the polarizing layer 21 to be produced.

(Polymerization initiator)
The composition for forming a polarizing layer may contain a polymerization initiator. The polymerization initiator can be used when a polymerizable liquid crystal compound is used as the liquid crystal compound, and is a compound capable of initiating a polymerization reaction of the polymerizable liquid crystal compound or the like. The polymerization initiator is preferably a photopolymerization initiator that generates active radicals by the action of light from the viewpoint of being independent of the phase state of the thermotropic liquid crystal.

Examples of the polymerization initiator include benzoin compounds, benzophenone compounds, alkylphenone compounds, acyl phosphine oxide compounds, triazine compounds, iodonium salts and sulfonium salts.

Examples of the benzoin compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether.

Examples of benzophenone compounds include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, 3,3 ′, 4,4′-tetra (tert-butylperoxycarbonyl) And benzophenone and 2,4,6-trimethylbenzophenone.

Examples of the alkylphenone compounds include diethoxyacetophenone, 2-methyl-2-morpholino-1- (4-methylthiophenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) ) Butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1,2-diphenyl-2,2-dimethoxyethane-1-one, 2-hydroxy-2-methyl-1 -[4- (2-hydroxyethoxy) phenyl] propan-1-one, 1-hydroxycyclohexyl phenyl ketone or 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propane-1-propane On-oligomer etc. are mentioned.

Examples of the acyl phosphine oxide compound include 2,4,6-trimethyl benzoyl diphenyl phosphine oxide or bis (2,4,6-trimethyl benzoyl) phenyl phosphine oxide.

Examples of triazine compounds include 2,4-bis (trichloromethyl) -6- (4-methoxyphenyl) -1,3,5-triazine and 2,4-bis (trichloromethyl) -6- (4-methoxy). Naphthyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (4-methoxystyryl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (5-Methylfuran-2-yl) ethenyl] -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (furan-2-yl) ethenyl] -1 , 3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (4-diethylamino-2-methylphenyl) ethenyl] -1,3,5-triazine or 2,4-bis (trichloro) Methyl) 6- [2- (3,4-dimethoxyphenyl) ethenyl] -1,3,5-triazine.

A commercially available thing can also be used for a polymerization initiator. Commercially available polymerization initiators include Irgacure (registered trademark) 907, 184, 651, 819, 250, 369, 379, 127, 754, OXE01, OXE02, or OXE03 (manufactured by Ciba Specialty Chemicals Inc.) Seikol (registered trademark) BZ, Z, or BEE (manufactured by SEIKO CHEMICAL CO., LTD.); Kayacure (registered trademark) BP 100, or UVI-6992 (manufactured by Dow Chemical Co.); Adeka Optomer SP-152, N-1717, N-1919, SP-170, Adeka Arkles NCI-831, Adeka Arkles NCI-930 (manufactured by ADEKA Co., Ltd.); TAZ-A, or TAZ-PP (manufactured by Nihon Shiber Hegner Co., Ltd.); TAZ- 104 (made by Sanwa Chemical Co., Ltd.) Etc. The. One type of polymerization initiator in the composition for forming a polarizing layer may be used, or two or more types of a plurality of polymerization initiators may be mixed and used according to the light source.

The content of the polymerization initiator in the composition for forming a polarizing layer can be appropriately adjusted according to the type of the polymerizable liquid crystal compound and the amount thereof, but the content is usually 0. 1 parts by mass relative to 100 parts by mass of the content of the polymerizable liquid crystal compound. The amount is 1 to 30 parts by mass, preferably 0.5 to 10 parts by mass, and more preferably 0.5 to 8 parts by mass. When the content of the polymerization initiator is in the above range, the polymerization can be performed without disturbing the alignment of the polymerizable liquid crystal compound.

(Sensitizer)
The composition for forming a polarizing layer may contain a sensitizer. The sensitizer can be suitably used when a polymerizable liquid crystal compound is used as a liquid crystal compound, and when a polymerizable liquid crystal compound having a photopolymerizable group is used, the sensitizer is a photosensitizer. It is preferably an agent. Examples of sensitizers include xanthone compounds such as xanthone and thioxanthone (eg, 2,4-diethylthioxanthone, 2-isopropylthioxanthone etc.); anthracene compounds such as anthracene and alkoxy group-containing anthracene (eg dibutoxyanthracene etc) And phenothiazine or rubrene and the like.

When the composition for forming a polarizing layer contains a sensitizer, the polymerization reaction of the polymerizable liquid crystal compound contained in the composition for forming a polarizing layer can be further promoted. The amount of the sensitizer used is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, and more preferably 0.5 to 3 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. Parts are more preferred.

(Polymerization inhibitor)
The composition for forming a polarizing layer may contain a polymerization inhibitor from the viewpoint of stably advancing the polymerization reaction. The polymerization inhibitor can be suitably used when a polymerizable liquid crystal compound is used as the liquid crystal compound, and the degree of progress of the polymerization reaction of the polymerizable liquid crystal compound can be controlled by the polymerization inhibitor.

Examples of the polymerization inhibitor include radical scavenging such as hydroquinone, alkoxy group-containing hydroquinone, alkoxy group-containing catechol (eg, butyl catechol etc.), pyrogallol, 2,2,6,6-tetramethyl-1-piperidinyloxy radical etc. Agents; thiophenols; β-naphthylamines or β-naphthols.

When the composition for forming a polarizing layer contains a polymerization inhibitor, the content of the polymerization inhibitor is preferably 0.1 to 10 parts by mass, more preferably 100 parts by mass of the content of the polymerizable liquid crystal compound. The amount is 0.5 to 5 parts by mass, more preferably 0.5 to 3 parts by mass. When the content of the polymerization inhibitor is in the above range, the polymerization can be performed without disturbing the alignment of the polymerizable liquid crystal compound.

(Leveling agent)
The composition for forming a polarizing layer may contain a leveling agent. The leveling agent is an additive having a function of adjusting the flowability of the composition and making the film obtained by applying the composition more flat, and is, for example, an organic modified silicone oil type, polyacrylate type or perfluoro type. An alkyl type leveling agent is mentioned. Specifically, DC3PA, SH7PA, DC11PA, SH28PA, SH29PA, SH30PA, ST80PA, ST86PA, SH8400, SH8700, FZ2123 (all manufactured by Toray Dow Corning Co., Ltd.), KP 321, KP 323, KP 324, KP 326, KP 340, KP341, X22-161A, KF6001 (all from Shin-Etsu Chemical Co., Ltd.), TSF400, TSF401, TSF410, TSF4300, TSF4440, TSF4446, TSF-4446, TSF4452, TSF4460 (all, Momentive Performance Materials Japan Ltd. Fluorinert (registered trademark) FC-72, FC-40, FC-43, FC-3283 (above, Sumitomo 3M Co., Ltd., Megafuck (registered trademark) R-08, R-30, R-90, F-410, F-411, F-443, F-445, F-470, F-477, F-479, F-482, F-483 (all available from DIC Corporation), F-Top (trade names) EF301, EF303, EF351, EF 352 (all manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd.), Surflon (registered trademark) S-381, S-382, S-383, S-393, S-101, S-105, KH -40, SA-100 (all available from AGC Seimi Chemical Co., Ltd.), under the trade names E1830 and E5844 (manufactured by Daikin Fine Chemical Laboratories), BM-1000, BM-1100, BYK-352, BY -353 or BYK-361N (both trade name: BM Chemie Co., Ltd.), and the like. Among them, polyacrylate leveling agents or perfluoroalkyl leveling agents are preferable.

When the composition for forming a polarizing layer contains a leveling agent, it is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 5 parts by mass, and still more preferably 100 parts by mass of the liquid crystal compound. 0.1 to 3 parts by mass. When the content of the leveling agent is within the above range, it is easy to horizontally align the liquid crystal compound, and the obtained polarizing layer tends to be smoother. When the content of the leveling agent with respect to the liquid crystal compound exceeds the above range, unevenness tends to easily occur in the obtained polarizing layer. In addition, the composition for polarizing layer formation may contain 2 or more types of leveling agents.

(Reactive additive)
The composition for forming a polarizing layer may contain a reactive additive. The reactive additive is preferably one having a carbon-carbon unsaturated bond and an active hydrogen reactive group in the molecule. The term "active hydrogen reactive group" as used herein refers to a group having reactivity with a group having active hydrogen such as carboxyl group (-COOH), hydroxyl group (-OH), amino group (-NH ₂ ) and the like. And glycidyl group, oxazoline group, carbodiimide group, aziridine group, imide group, isocyanate group, thioisocyanate group, maleic anhydride group and the like are representative examples. The number of carbon-carbon unsaturated bonds or active hydrogen reactive groups contained in the reactive additive is usually 1 to 20, and preferably 1 to 10.

In the reactive additive, at least two active hydrogen reactive groups are preferably present, and in this case, the active hydrogen reactive groups may be the same or different.

The carbon-carbon unsaturated bond possessed by the reactive additive may be a carbon-carbon double bond, a carbon-carbon triple bond, or a combination thereof, but is preferably a carbon-carbon double bond. Among them, it is preferable that the reactive additive contains a carbon-carbon unsaturated bond as a vinyl group and / or a (meth) acrylic group. Furthermore, a reactive additive in which the active hydrogen reactive group is at least one selected from the group consisting of an epoxy group, a glycidyl group and an isocyanate group is preferable, and a reactive additive having an acrylic group and an isocyanate group is more preferable. .

Specific examples of the reactive additive include compounds having a (meth) acrylic group and an epoxy group such as methacryloxy glycidyl ether and acryloxy glycidyl ether; (meth) acrylic groups and oxetane such as oxetane acrylate and oxetane methacrylate A compound having a group; a compound having a (meth) acrylic group and a lactone group such as lactone acrylate and lactone methacrylate; a compound having a vinyl group and an oxazoline group such as vinyl oxazoline and isopropenyl oxazoline; isocyanato methyl acrylate And oligomers of compounds having a (meth) acrylic group and an isocyanate group, such as isocyanatomethyl methacrylate, 2-isocyanatoethyl acrylate or 2-isocyanatoethyl methacrylate. That. In addition, compounds having a vinyl group or vinylene group and an acid anhydride, such as methacrylic anhydride, acrylic anhydride, maleic anhydride or vinyl maleic anhydride, may be mentioned. Among them, methacryloxy glycidyl ether, acryloxy glycidyl ether, isocyanato methyl acrylate, isocyanato methyl methacrylate, vinyl oxazoline, 2-isocyanato ethyl acrylate, 2-isocyanato ethyl methacrylate or the above-mentioned oligomers are preferable, isocyanato methyl acrylate, Particularly preferred is 2-isocyanatoethyl acrylate or the above mentioned oligomers.

Specifically, a compound represented by the following formula (Y) is preferable.

[Wherein, in the formula (Y), n represents an integer of 1 to 10, R ^{1 ′} represents a divalent aliphatic or alicyclic hydrocarbon group having 2 to 20 carbon atoms, or 2 Represents a substituted aromatic hydrocarbon group. Two R ^{2 ′ in} each repeating unit is a group in which one is —NH— and the other is> N—C (= O) —R ^{3 ′} . R ^{3 '} represents a group having a hydroxyl group or a carbon-carbon unsaturated bond.
^'Of at least one R ^3' formula (Y) in R ³ is a carbon - is a group having a carbon unsaturated bond. ]

Among the reactive additives represented by the formula (Y), a compound represented by the following formula (YY) (hereinafter sometimes referred to as a compound (YY)) is particularly preferable (where n is the same as above). Is the meaning).

For the compound (YY), commercially available products can be used as they are or purified as needed. As a commercial item, for example, Laromer (registered trademark) LR-9000 (manufactured by BASF Corporation) may be mentioned.

When the composition for forming a polarizing layer contains a reactive additive, the content of the reactive additive is usually 0.01 to 10 parts by mass, preferably 0.1 to 100 parts by mass of the liquid crystal compound. 5 parts by mass.

(Protective layer lamination process)
In the protective layer laminating step, as shown in FIG. 3C, a covering region 35a for covering the polarizing layer 21 and the polarizing layer 21 are exposed on the polarizing layer 21 of the laminated film 62 prepared in the preparation step. And a protective layer 35 having an exposed area 35b. Thereby, the laminated film 63 with a protective layer can be obtained. The exposed region 35 b can be, for example, an opening of the protective layer 35. The coated region 35 a contacts the polarizing layer 21 when the liquid which can reduce the content of the dichroic dye in the polarizing layer 21 described later and the laminated film 63 with a protective layer are brought into contact with each other. Can be suppressed. On the other hand, in the exposed area 35 b of the protective layer 35, the liquid can be brought into contact with the polarizing layer 21.

As described later, when the polarizing layer 21 comes in contact with the liquid, the liquid penetrates into the polarizing layer 21 and loses the function of the dichroic dye as a dye. Therefore, it is preferable to form the exposed area 35b in correspondence with the area in the polarizing layer 21 in which the content of the dichroic dye is reduced. For example, when manufacturing the polarizing film 1 shown to FIG. 1 (a) and (b), it is preferable to determine the shape according to the shape of 2nd area | region 11 b. For example, if the plan view shape of the second region 11b is circular; oval; oval; polygon such as triangle, square, rectangle, rhombus, etc .; linear; It may be formed corresponding to the shape of.

For example, when the exposed area 35b is circular, the diameter is preferably 5 cm or less, more preferably 3 cm or less, and still more preferably 2 cm or less. When the exposed area 35b is elliptical or oval, the major axis is preferably 5 cm or less, more preferably 3 cm or less, and still more preferably 2 cm or less. When the exposed area 35b is a polygon, the diameter of a virtual circle drawn so as to be inscribed in the polygon is preferably 5 cm or less, more preferably 3 cm or less, and 2 cm or less. More preferable. As described later, since the liquid penetrates into the liquid crystal layer, the size of the exposed area 35b may be formed to be slightly smaller than the size of the second area 11b.

Further, it is preferable that the covering region 35 a of the protective layer 35 be formed to correspond to the region in the polarizing layer 21 in which the content of the dichroic dye is not reduced. For example, when manufacturing the polarizing film 1 shown to FIG. 1 (a) and (b), it is preferable to determine the shape according to the shape of 1st area | region 11 a.

As the protective layer 35, what formed the area | region used as the exposed area | region 35b in a sheet-like base material can be used. In the area to be the exposed area 35b, a predetermined portion of the sheet-like substrate is mechanically removed by punching, cutting plotter, water jet or the like, or a predetermined portion of the sheet-like substrate is removed by laser ablation, chemical dissolution or the like. It can be formed by a method or the like.

The sheet-like base material forming the protective layer 35 is insoluble in a liquid when brought into contact with a liquid that can reduce the content of the dichroic dye in the liquid crystal layer described later, and the liquid is removed The material is not particularly limited as long as the material has durability in ultraviolet irradiation performed after contacting a liquid material. As a sheet-like base material which forms protective layer 35, it can form using the same material as base material layer 13 mentioned above, for example, and forming using resin base material especially is preferred, and protective layer 35 is preferred. It is more preferable to use a polyester resin such as polyethylene terephthalate that easily suppresses deformation of a region (for example, an opening) to be the exposed region 35b.

The protective layer 35 preferably has an adhesive layer for bonding to the polarizing layer 21. Since the protective layer 35 is peeled off as described later, the adhesive layer is preferably peelable relative to the polarizing layer 21. The thickness of the protective layer 35 is usually 20 μm or more, preferably 30 μm or more, and usually 250 μm or less, preferably 200 μm or less.

(Decoloring process)
In the decoloring step, the laminated film 63 with a protective layer obtained in the protective layer laminating step is brought into contact with a liquid that can reduce the content of the dichroic dye in the polarizing layer 21, thereby forming part of the polarizing layer 21. A decolorized laminated film 64 can be obtained in which the content of the dichroic dye is reduced in the region (FIG. 3 (d)). The protective layer 35 of the laminated film 63 with protective layer has a coated area 35 a for covering the polarizing layer 21 and an exposed area 35 b for exposing the polarizing layer 21. It can be in contact with the polarizing layer 21. Thereby, in the area | region which contacted the liquid among the polarizing layers 21, the content rate of a dichroic dye can be reduced.

The contact between the protective film with a protective layer 63 and the liquid can be carried out by immersing the protective film with a protective layer 63 in the liquid, or by applying, spraying or dropping the liquid on the protective film with a protective layer 63 It is preferable to carry out by the method of immersing the laminated film 63 with a protective layer in a liquid. As a result, the liquid comes in contact with the surface of the polarizing layer 21 exposed from the exposed region 35 b of the protective layer 35 in the polarizing layer 21 and penetrates the inside of the polarizing layer 21. Although the details are not clear, the liquid that has penetrated the inside of the polarizing layer 21 decomposes the dichroic dye in the polarizing layer 21 or reacts with the dichroic dye or the like to form a dye of the dichroic dye. It is thought that the function of As a result, the second region 11b, which is a region having a smaller content of the dichroic dye than the other regions, is formed in a part of the polarizing layer 21, and the decolorized laminated film 64 having the liquid crystal layer 11 (FIG. d) can be obtained.

In the area of the surface of the polarizing layer 21 covered by the covering area 35 a of the protective layer 35, the polarizing layer 21 does not directly contact the liquid, so that the liquid hardly penetrates into the polarizing layer 21 and the dichroic dye It is hard to be lost. On the other hand, in the area of the polarizing layer 21 exposed from the exposed area 35 b of the protective layer 35, the polarizing layer 21 is in direct contact with the liquid, so the liquid easily penetrates into the polarizing layer 21. Are easily lost. Therefore, in the decolorized laminated film 64 shown in FIG. 3D, the second polarization region is a low polarization region in which the content of the dichroic dye is smaller than the other regions in the region corresponding to the exposed region 35b of the polarization layer 21. The liquid crystal layer 11 having the region 11 b can be formed.

As described above, by using the laminated film 63 with the protective layer in which the exposed area 35 b of the protective layer 35 is disposed in the area where the content of the dichroic dye is to be reduced in the polarizing layer 21, the desired position of the polarizing layer 21 is obtained. The liquid crystal layer 11 can be formed in which the content of the dichroic dye is reduced. However, since the liquid penetrates the inside of the polarizing layer 21 and loses the function of the dichroic dye, the liquid penetrates to a region where it is not necessary to reduce the content of the dichroic dye and the dichroism occurs. The thickness of the protective layer 35, the size of the exposed area 35b, the concentration of the liquid, the immersion time of the laminated film with the protective layer in the liquid, the laminated film with the protective layer 63 so as not to reduce the pigment content. It is preferable to adjust the application amount, the spray amount, the dripping amount, and the like of the liquid to the surface.

The liquid that can reduce the content of the dichroic dye in the polarizing layer 21 is not particularly limited as long as the content of the dichroic dye can be reduced, but, for example, peroxide (hydrogen peroxide, sodium percarbonate, etc.) or Chlorine compounds (sodium hypochlorite etc.), acids (sulfuric acid, nitric acid, hexafluorophosphoric acid), alkalis (sodium hydroxide, potassium hydroxide) etc. can be used as appropriate. Among these, acids such as sulfuric acid, nitric acid and hexafluorophosphoric acid are preferable. These liquids may be used alone or in combination.

The contact conditions for contacting the protective film with the protective layer 63 and the liquid may be appropriately selected according to the thickness of the polarizing layer 21 and the range in which the content of the dichroic dye is reduced. The concentration of the liquid is, for example, preferably 20 to 80% by mass, and more preferably 30 to 70% by mass. Further, the temperature of the liquid is preferably 50 to 150 ° C., and more preferably 80 to 120 ° C.

In the decoloring step, the protective film-provided laminated film 63 is brought into contact with the liquid to form a region in which the dichroic dye content is lower than that of the other regions in a part of the polarizing layer 21. It is preferable to provide a first washing step to wash away. The first washing step can be performed using an organic solvent such as water or alcohol.

(Peeling process)
In the peeling step, the protective layer 35 is peeled from the decolorized laminated film 64 obtained in the decoloring step. Thereby, the polarizing film 1 (FIGS. 1A and 1B) in which the second region 11b having a smaller percentage of the dichroic dye content than the other regions is formed in a part of the liquid crystal layer 11. You can get

The polarizing film 1 shown in FIG. 1 (b) can also be used by peeling off the base material layer 13. In this case, the alignment layer 12 may be peeled off together with the base layer 13. For example, peeling of the base material layer 13 can also be performed after bonding the liquid-crystal layer 11 of the polarizing film 1 to the member, retardation layer, etc. which make a display apparatus.

(Method to manufacture polarizing film continuously)
The manufacturing method of the polarizing film 1 can preferably be continuously manufactured by a Roll to Roll type | mold. In this case, the laminated film wound in a roll may be prepared in the preparation step, and the laminated film may be conveyed while being unwound and the protective layer laminating step, the decoloring step, and the peeling step may be continuously performed. In the protective layer laminating step, the protective layer wound in a roll may be conveyed while being unwound, and the protective layer may be bonded to the laminated film to obtain a laminated film with a protective layer. In the decoloring step, the laminated film with the protective layer is continuously transported, and is passed through a liquid bath filled with the liquid, or the liquid is coated, sprayed or continuously transported while the laminated film with the protective layer is continuously transported. It may be dropped to obtain a decolorized laminated film. In the peeling step, the protective layer may be continuously peeled from the decolorized laminated film, and the polarizing film may be wound into a roll to form a wound body. The polarizing film manufactured continuously as mentioned above can have a length of 10 m or more, for example.

When the preparation step has an alignment layer forming step, the base layer wound in a roll is conveyed while being unwound, and the base layer is continuously coated with the composition for forming an alignment layer by a coating device. The orientation layer may be formed by processing. In the case where the preparation step has a polarizing layer forming step, the polarizing layer forming composition is provided on the side on which the alignment layer of the alignment layer-provided base layer is formed while continuously conveying the alignment layer-containing base layer. It may be coated to form a polarizing layer.

In the polarizing film 1 manufactured by the first manufacturing method, the difference in thickness between the first region 11 a and the second region 11 b can be reduced to, for example, 2 μm or less. You can get Thereby, even if it bonds another film on the polarizing layer 21 with an adhesive etc., another film can be laminated | stacked, without biting in air bubbles.

<Method of producing polarizing film (second method of production)>
The polarizing film 1 can also be manufactured by the 2nd manufacturing method shown below other than the above-mentioned 1st manufacturing method. FIG. 4: is a schematic sectional drawing which shows an example of the liquid thing contact process in the manufacturing method of the polarizing film 1 shown in FIG.1 (b). The second production method of the polarizing film 1 is
Preparing a laminated film 62 (FIG. 3B) having a polarizing layer 21 containing a liquid crystal compound and a dichroic dye on at least one side of a substrate layer 13;
By bringing a partial region of the polarizing layer 21 of the laminated film 62 into contact with a liquid capable of reducing the dichroic dye content in the polarizing layer 21, the dichroic dye content in the partial region The liquid contact process (FIG. 4) which reduces the, and, thereby, the polarizing film 1 shown in FIG. 1 (a) and (b) can be manufactured.

The preparation steps in this second manufacturing method are the same as the preparation steps in the first manufacturing method described based on FIGS. 3 (a) and 3 (b). By this preparation process, the laminated film 62 having the polarizing layer 21 is prepared.

In this second manufacturing method, a partial region of the polarizing layer 21 on the laminated film 62 is brought into contact with the liquid (FIG. 4). The liquid used at this time can reduce the content of the dichroic dye in a partial region of the polarizing layer 21 and is the same as the liquid used in the decoloring step in the first manufacturing method described above. The following liquid can be used. As a method of bringing a liquid material into contact with a partial region of the polarizing layer 21, for example, as shown in FIG. 4, a so-called ink jet method etc. in which the liquid material is dropped and applied to this partial region can be mentioned. . By bringing the polarizing layer 21 into contact with the liquid, the liquid penetrates into a partial region of the polarizing layer 21, and the content of the dichroic dye can be reduced to form a low polarization region.

The second manufacturing method preferably includes a second cleaning step of washing the liquid on the polarizing layer 21 after the polarizing layer 21 and the liquid are brought into contact with each other. The second washing step can be performed using an organic solvent such as water or alcohol used in the first washing step in the first production method. Thereby, the polarizing film 1 shown in FIG.1 (b) can be obtained.

In the second production method, as in the first production method, the polarizing film 1 can be continuously produced, for example, by the Roll to Roll method. In this case, the laminated film wound in a roll shape may be prepared in the preparation step, and the laminated film may be conveyed while being unwound and the liquid contacting step may be continuously performed. In the liquid contact step, while continuously conveying the laminated film, the liquid may be dropped and applied to obtain a polarizing film, and the obtained polarizing film may be wound into a roll to form a wound body. The polarizing film manufactured continuously as mentioned above can have a length of 10 m or more, for example.

Also by this second manufacturing method, the difference in thickness between the first region 11a and the second region 11b can be reduced to, for example, 2 μm or less, and the polarizing film 1 having no step can be obtained. Thereby, even if it bonds another film on the polarizing layer 21 with an adhesive etc., another film can be laminated | stacked, without biting in air bubbles.

<Method of manufacturing circularly polarizing plate>
The circularly polarizing plate can be manufactured by laminating the polarizing film 1 and the retardation layer. As described above, in the case where the polarizing film is a continuously produced long polarizing film having a length of 10 m or more, a long retardation layer having a length of 10 m or more is used as the retardation layer, and both are continuously produced. It is preferable to form a long laminated body by laminating | stacking a long polarizing film and a long retardation layer, conveying to. At this time, it is preferable to apply a pressure-sensitive adhesive or an adhesive to at least one of the long polarizing film and the long retardation layer to laminate the both.

The manufacturing method of a circularly polarizing plate is a sheet of a predetermined size in order to attach the polarizing film to a display device of a predetermined size, etc., by attaching a long laminate obtained by laminating a long polarizing film and a long retardation layer to a display of a predetermined size. It may have a process of cutting into In the cutting step, the long laminate is preferably cut in at least one of the length direction and the width direction of the long laminate. In this case, it is preferable to determine the cutting position in the long laminate so that the second region 11b of the liquid crystal layer 11 is disposed at a predetermined position in the cut sheet.

The present invention will be more specifically described based on examples. However, the present invention is not limited by these examples.

[Visual sensitivity correction polarization degree (Py) and visual sensitivity correction transmittance (Ty)]
(Preparation of sample for evaluation)
The composition for forming an alignment layer and the composition for forming a polarizing layer used in each example, comparative example and reference example were prepared. Moreover, what cut out the same film as what was used as a base material layer in each Example, a comparative example, and a reference example in 40 mm x 40 mm was prepared as a base material layer of the sample for evaluation. Using these, in Examples 1 and 2 and Comparative Examples and Reference Examples, the protective layer is not used, and in Example 3, the entire surface of the polarizing layer is brought into contact with the solution instead of dropping the solution partially on the polarizing layer. Except for the above, procedures similar to the production of the polarizing films of the respective examples, comparative examples and reference examples were carried out to obtain samples for evaluation.

(Visual sensitivity correction degree of polarization (Py) and visual sensitivity correction transmittance (Ty))
For the sample for evaluation, the luminosity correction single transmittance (Ty) and the luminosity correction polarization degree (Py) were calculated in the following procedure. Set the folder with polarizer to the spectrophotometer (UV-3150 manufactured by Shimadzu Corporation) in the transmittance axis direction (T ₁ ) and the transmittance (T ₂ ) in the absorption axis direction in the wavelength range of 380 nm to 780 nm. The apparatus was used to measure by the double beam method. In the folder, a mesh was provided to cut the light amount by 50% on the reference side. The transmittance and polarization degree at each wavelength are calculated using the following (Equation 1) and (Equation 2), and the visibility is corrected with a 2-degree field of view (C light source) of JIS Z 8701, and the visibility correction transmittance (Ty) and the visibility correction polarization degree (Py) were calculated.
Degree of polarization [%] = {(T ₁ −T ₂ ) / (T ₁ + T ₂ )} × 100 (Equation 1)
Single transmittance [%] = (T ₁ + T ₂ ) / 2 (equation 2)

Example 1
(Production of Composition for Forming Alignment Layer)
The following components were mixed, and the obtained mixture was stirred at 80 ° C. for 1 hour to obtain a composition for forming an alignment layer which is a composition for forming a photo alignment film.
・ 2 parts of polymer having photoreactive group shown below

Solvent: 98 parts of o-xylene

(Production of composition for forming polarizing layer)
The following components were mixed and stirred at 80 ° C. for 1 hour to obtain a composition for forming a polarizing layer. As the dichroic dye, the azo dye described in the example of JP-A-2013-101328 was used.
-75 parts of a polymerizable liquid crystal compound represented by the formula (1-6)

-25 parts of a polymerizable liquid crystal compound represented by the formula (1-7)

-2.8 parts of the dichroic dye (1) shown below

-2.8 parts of the dichroic dye (2) shown below

-2.8 parts of the dichroic dye (3) shown below

· Polymerization initiator shown below 6 parts 2-dimethylamino-2-benzyl-1- (4-morpholinophenyl) butan-1-one (IRGACURE 369; manufactured by Ciba Specialty Chemicals)
-Leveling agent shown below 1.2 parts Polyacrylate compound (BYK-361N; manufactured by BYK-Chemie)
・ 250 parts of solvents shown below Cyclopentanone

(Manufacture of polarizing film)
A triacetyl cellulose film (KC4UY-TAC manufactured by Konica Minolta, thickness 40 μm) as a base material layer was cut out to 20 × 20 mm, and the surface was subjected to corona treatment (AGF-B10, manufactured by Kasuga Denki Co., Ltd.). After applying the composition for alignment layer formation using the bar coater on the film surface to which the corona treatment was given, it dried for 1 minute with the drying oven set to 120 degreeC, and obtained the coating layer for alignment layers. The alignment layer is irradiated with polarized UV light at an integrated light quantity of 50 mJ / cm ² (based on 313 nm) using a polarized UV irradiation device (SPOT CURE SP-7; manufactured by Ushio Inc.) on the coating layer for alignment layer. It formed. After applying the composition for polarizing layer formation using the bar coater on the obtained orientation layer, it dried for 1 minute with the drying oven set to 110 degreeC. After that, the liquid crystal is irradiated with ultraviolet light (in nitrogen atmosphere, wavelength: 365 nm, integrated light amount at wavelength 365 nm: 1000 mJ / cm ² ) using a high pressure mercury lamp (UNIQUEUR VB-15201BY-A, manufactured by USHIO INC.) The polarizing layer in which the compound and the dichroic dye were oriented was obtained. A protective layer (AY-638 manufactured by Fujimori Kogyo Co., Ltd., having an opening formed on the polarizing layer by a hole-piercing punch (AY-638 with a 15 μm thick adhesive layer provided on a 38 μm thick polyester film) ) Was immersed in a 50 wt% solution of propylene carbonate in diphenyl 4-thiophenoxyphenylsulfonium hexafluorophosphate (CPI-100P manufactured by San-Apro Co., Ltd.) at 120 ° C. for 60 seconds. Thereafter, the protective layer was peeled off to obtain a polarizing film.

When the appearance of the obtained polarizing film was visually observed, it was possible to clearly confirm the circular area (low polarization area) where the polarizing layer was not present, and it was possible to obtain a polarizing film having a polarization area and a low polarization area. all right. Moreover, the sample for evaluation was produced in the above-mentioned procedure, and the visual sensitivity correction | amendment transmittance | permeability (Ty) and the visual sensitivity correction polarization degree (Py) were computed. The results are shown in Table 1.

Example 2
Instead of using a triacetyl cellulose film as a base material layer, the surface of a quarter wave plate (Zeonor film, Nippon Zeon Co., in-plane retardation value Ro: 138 nm) which is a uniaxially stretched film of a cyclic olefin resin A polarizing film was obtained in the same manner as in Example 1 except that the hard-coated film was used and laminated so that the slow axis and the absorption axis of the polarizing layer were 45 °. Moreover, the sample for evaluation was produced in the above-mentioned procedure, and the visual sensitivity correction | amendment transmittance | permeability (Ty) and the visual sensitivity correction | amendment degree of polarization (Py) were computed. The results are shown in Table 1.

[Example 3]
Instead of bonding a protective layer in which an opening is formed by using a punching punch, a diphenyl 4-thiophenoxyphenylsulfonium hexafluorophosphate (San-Apro stock) is partially formed on a polarizing layer using a dropper instead of using a syringe. A polarizing film was obtained in the same manner as in Example 1 except that a 50 wt% solution of propylene carbonate in a company's CPI-100P) was dropped. Moreover, the sample for evaluation was produced in the above-mentioned procedure, and the visual sensitivity correction | amendment transmittance | permeability (Ty) and the visual sensitivity correction | amendment degree of polarization (Py) were computed. The results are shown in Table 1.

Comparative Example
Example 6 was carried out in the same manner as Example 1, except that methanol was used at normal temperature instead of a 50 wt% solution of propylene carbonate in diphenyl 4-thiophenoxyphenyl sulfonium hexafluorophosphate (CPI-100P manufactured by San-Apro Co., Ltd.). A polarizing film was obtained. When the appearance of the obtained polarizing film was visually observed, it was found that the region where the polarizing layer was not present could not be confirmed, and that a polarizing film having a polarizing region and a low polarizing region was not obtained. Moreover, the sample for evaluation was produced in the above-mentioned procedure, and the visual sensitivity correction | amendment transmittance | permeability (Ty) and the visual sensitivity correction | amendment degree of polarization (Py) were computed. The results are shown in Table 1.

[Reference example]
A polarizing film was obtained in the same manner as Example 1, except that a 50 wt% solution of propylene carbonate in diphenyl 4-thiophenoxyphenylsulfonium hexafluorophosphate (CPI-100P, manufactured by San-Apro Co., Ltd.) was not used. When the appearance of the obtained polarizing film was visually observed, it was found that the region where the polarizing layer was not present could not be confirmed, and that a polarizing film having a polarizing region and a low polarizing region was not obtained. Moreover, the sample for evaluation was produced in the above-mentioned procedure, and the visual sensitivity correction | amendment transmittance | permeability (Ty) and the visual sensitivity correction | amendment degree of polarization (Py) were computed. The results are shown in Table 1.

In addition, the values of the visibility correction transmittance (Ty) and the visibility correction polarization degree (Py) measured in each example, comparative example and reference example shown in Table 1 are the visibility correction transmittance of the base material layer ( Ty) and the visibility correction polarization degree (Py) value, the visibility correction transmittance (Ty) of the base material layer alone is 92%, and the visibility correction polarization degree of the base material layer (Ty) Since the value of Py) is 0%, when the base material layer is removed in each of the examples, comparative examples and reference examples shown in Table 1, the value of the visibility correction transmittance (Ty) is the value shown in Table 1 The value of the degree of visibility correction polarization (Py) is considered to be the same as the value shown in Table 1.

DESCRIPTION OF SYMBOLS 1 Polarizing film, 5a-5c circularly polarizing plate, 11 liquid crystal layer, 11a 1st area | region, 11b 2nd area | region, 12 orientation layer, 13 base material layer, 15 retardation layer, 21 polarization layer, 35 protective layer, 35a coating area | region , 35b exposed area, 61 base layer with alignment layer, 62 laminated film, 63 laminated film with protective layer, 64 decolorized laminated film.

Claims

A polarizing film having a liquid crystal layer,
The liquid crystal layer contains a liquid crystal compound and has at least two regions distinguished by the value of the degree of polarization correction for polarization,
The polarizing film, wherein the at least two regions have different dichroic dye contents.
Furthermore, a base material layer,
An orientation layer laminated on at least one side of the substrate layer,
The polarizing film according to claim 1, wherein the liquid crystal layer is laminated on the alignment layer.
The polarizing film according to claim 2, wherein the alignment layer comprises a photoalignable polymer.
The polarizing film according to any one of claims 1 to 3, wherein the liquid crystal compound comprises a polymerizable liquid crystal compound.
The liquid crystal layer has a first region containing a dichroic dye, and a second region containing a smaller amount of dichroic dye than the first region.
The visibility correction polarization degree of the first area is 90% or more.
The polarizing film according to any one of claims 1 to 4, wherein the visibility correction polarization degree of the second region is 10% or less.
The liquid crystal layer has a first region containing a dichroic dye, and a second region containing a smaller amount of dichroic dye than the first region.
The visibility correction single transmittance of the first region is 35% or more,
The polarizing film according to any one of claims 1 to 5, wherein the transmittance of the second region in the luminosity correction alone is 80% or more.
The second region is circular, elliptical, oval or polygonal in plan view shape,
When the second region is circular, the diameter is 5 cm or less.
When the second region is elliptical or oblong, the major axis is 5 cm or less.
The polarizing film according to claim 5 or 6, wherein when the second region is a polygon, a diameter of an imaginary circle drawn so that the polygon is inscribed is 5 cm or less.
The polarizing film according to any one of claims 5 to 7, wherein the first region exhibits a Bragg peak in X-ray diffraction measurement.
Furthermore, it has a substrate layer,
The polarizing film according to any one of claims 1 to 8, wherein the base material layer has a quarter wave plate function.
The polarizing film according to any one of claims 1 to 9, wherein the length of the polarizing film is 10 m or more.
A circularly polarizing plate formed by laminating the polarizing film according to any one of claims 1 to 8 and 10 and a retardation layer having a 1⁄4 wavelength plate function.
Preparing a laminated film having a polarizing layer containing a liquid crystal compound and a dichroic dye on at least one side of the substrate layer;
A dichroic dye in a partial region of the polarizing layer is brought into contact with a partial region of the polarizing layer of the laminated film by bringing a liquid capable of reducing the content of the dichroic dye in the polarizing layer into contact. And D. a liquid contacting step of reducing the content of.
The liquid contacting step is
A protective layer is formed on the polarizing layer of the laminated film prepared in the preparation step, by laminating a protective layer having a coated area for covering the polarizing layer and an exposed area for exposing the polarizing layer. A protective layer laminating step of obtaining a laminated film
By bringing the laminated film with the protective layer into contact with a liquid capable of reducing the content of the dichroic dye in the polarizing layer, the content of the dichroic dye is reduced in a partial region of the polarizing layer A decoloring process to obtain a decolorized laminated film,
The manufacturing method of the polarizing film of Claim 12 which has the peeling process which peels the said protective layer from the said decolorization laminated | multilayer film.
The exposed area in the protective layer is circular, elliptical, oval or polygonal in plan view shape,
When the exposed area is circular, the diameter is 5 cm or less.
When the exposed area is elliptical or oval, the major axis is 5 cm or less.
The method for producing a polarizing film according to claim 13, wherein when the exposed area is a polygon, a diameter of a virtual circle drawn so that the polygon is inscribed is 5 cm or less.
The preparation process is
An alignment layer forming step of coating the composition for forming an alignment layer on one side of the base material layer to form an alignment layer;
A polarizing layer forming step of applying the composition for forming a polarizing layer containing the liquid crystal compound and the dichroic dye on the surface of the base layer on which the alignment layer is formed, thereby forming the polarizing layer; The method for producing a polarizing film according to any one of claims 12 to 14, wherein
The composition for forming an alignment layer contains a photoalignable polymer,
The polarizing film according to claim 15, wherein the alignment layer forming step forms the alignment layer by irradiating polarized light on the coating layer for an alignment layer formed by applying the composition for forming an alignment layer. Production method.
The liquid crystal compound is a polymerizable liquid crystal compound,
17. The polarizing layer-forming step according to claim 15 or 16, wherein the polarizing layer is formed by applying an active energy ray to the coating layer for a polarizing layer formed by applying the composition for forming a polarizing layer. Of producing a polarizing film.
The method for producing a polarizing film according to any one of claims 12 to 17, wherein the polarizing film has a length of 10 m or more.
A circle having a retardation layer laminating step of laminating a polarizing film produced by the method for producing a polarizing film according to any one of claims 12 to 18 and a retardation layer having a quarter wave plate function. The manufacturing method of a polarizing plate.
The polarizing film is a long polarizing film having a length of 10 m or more,
The retardation layer is a long retardation layer having a length of 10 m or more,
In the retardation layer laminating step, an elongated laminate is formed by laminating the elongated polarizing film and the elongated retardation layer.
Furthermore, the manufacturing method of the circularly-polarizing plate of Claim 19 which has a cutting process which cut | judges the said elongate laminated body to a sheet.