KR20200080244A - Manufacturing method of polarizing film and polarizing film - Google Patents

Abstract

The manufacturing method of a polarizing film is a preparation process of preparing a laminated film which has a polarizing layer containing a dichroic dye on at least one side of a base material layer, and a coating region for coating the polarizing layer on the polarizing layer of the laminated film The protective layer lamination process of obtaining a protective layer-forming laminated film by laminating a protective layer having an exposed region for exposing the polarizing layer, and the protective layer-forming laminated film in contact with a dissolving solution capable of dissolving the polarizing layer It has a solution contacting step of obtaining a patterned polarizing layer forming film having a patterned polarizing layer formed by removing a portion of the layer, and a peeling step of peeling off the protective layer from the patterned polarizing layer forming film.

Description

Manufacturing method of polarizing film and polarizing film

The present invention relates to a method of manufacturing a polarizing film and a polarizing film, and more particularly, to a manufacturing method of a polarizing film having a layer containing a liquid crystal compound and a dichroic dye, and a polarizing film.

Organic EL display devices using organic light-emitting diodes (OLEDs) can not only be lighter or thinner than liquid crystal displays, but also can achieve high image quality such as wide viewing angles, fast response speeds, and high contrast. , Digital cameras, etc. are used in various fields. In an organic EL display device, it is known to improve the antireflection performance using a circular polarizing plate or the like in order to suppress a decrease in visibility due to reflection of external light.

As a polarizing film used for such a circular polarizing plate, in Japanese Unexamined Patent Publication No. 2015-206852 (Patent Document 1) and Japanese Unexamined Patent Publication No. 2015-212823 (Patent Document 2), a liquid crystal cured film patterned on a substrate is laminated. One pattern polarizing film is described.

Japanese Patent Application Publication No. 2015-206852 Japanese Patent Application Publication No. 2015-212823

An object of the present invention is to provide a method for manufacturing a new polarizing film having at least two regions having different visibility-correcting polarizations and a polarizing film.

The present invention provides a method for producing a polarizing film shown below and a polarizing film.

[1] a preparation step of preparing a laminated film having a polarizing layer containing a dichroic dye on at least one side of the base layer;

A protective layer laminating process for obtaining a protective layer-forming laminated film by laminating a protective layer having a coating region for coating the polarizing layer and an exposed region for exposing the polarizing layer on the polarizing layer of the laminated film,

The solution contacting step of obtaining a patterned polarizing layer forming film having a patterned polarizing layer formed by removing a portion of the polarizing layer by bringing the protective layer forming laminated film into contact with a dissolving solution capable of dissolving the polarizing layer. and,

The manufacturing method of a polarizing film which has a peeling process which peels the said protective layer from the said patterned polarizing layer forming film.

[2] The preparation process,

An alignment layer forming process of forming an alignment layer by coating a composition for forming an alignment layer on one side of the base layer;

The method according to [1], having a polarizing layer forming step of forming a polarizing layer by coating a composition for forming a polarizing layer containing a liquid crystal compound and the dichroic dye on a side of the substrate layer on which the alignment layer is formed. Manufacturing method of polarizing film.

[3] The composition for forming an alignment layer contains a photo-alignment polymer,

The said alignment layer formation process is a manufacturing method of the polarizing film as described in [2] which forms a said alignment layer by carrying out polarization irradiation to the coating layer for alignment layers formed by coating the said composition for forming an alignment layer.

[4] The polarizing layer is a layer in which a polymerizable liquid crystal compound is aligned,

In the polarizing layer forming step, the method for producing a polarizing film according to [2] or [3], wherein the polarizing layer is formed by applying active energy ray to a coating layer for a polarizing layer formed by coating the composition for forming the polarizing layer. .

[5] The method for producing a polarizing film according to any one of [2] to [4], wherein the polarizing layer exhibits a Bragg peak in X-ray diffraction measurement.

[6] The exposed area has a circular, elliptical, oval, or polygonal shape when viewed in a plane,

When the exposed area is circular, the diameter is 5 cm or less,

The long diameter when the exposed area is oval or elliptical is 5 cm or less,

When the said exposed area is a polygon, the diameter of the virtual circle drawn so that the said polygon is inscribed is 5 cm or less, The manufacturing method of any one of [1]-[5].

[7] The method for producing a polarizing film according to any one of [1] to [6], wherein the polarizing film has a length of 10 m or more.

[8] The method for producing a polarizing film according to any one of [1] to [7], wherein the base layer has a 1/4 wavelength plate function.

[9] A circular polarizing plate having a retardation layer lamination step of laminating a retardation layer having a 1/4 wavelength plate function and a polarizing film produced by the method for producing a polarizing film according to any one of [1] to [7]. Manufacturing method.

[10] 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 lamination process, the elongated polarizing film and the elongated retardation layer are laminated to form a long elongated laminate,

Furthermore, the manufacturing method of the circular polarizing plate as described in [9] which has a cutting process of cutting the said long laminated body into single sheets.

[11] A polarizing film having a polarization region and a low polarization region having a lower visibility correction polarization than the polarization region,

The polarization region contains a liquid crystal compound and a dichroic dye, and the visibility correction polarization degree is 90% or more,

The low polarization region does not contain a liquid crystal compound and a dichroic dye,

The low polarization region has a circular, elliptical, elliptical, or polygonal shape when viewed in a plane,

When the low polarization region is circular, the diameter is 5 cm or less,

The long diameter when the low polarization region is oval or elliptical is 5 cm or less,

When the low polarization region is a polygon, the diameter of the virtual circle drawn so that the polygon is inscribed is 5 cm or less, a polarizing film.

[12] The polarizing film according to [11], wherein the low polarization region has a visibility correction polarization degree of 10% or less.

[13] The polarization region has a visibility-adjustable simple substance transmittance of 35% or more,

The polarization film according to [11] or [12], wherein the low-polarization region has a visibility correction simple substance transmittance of 80% or more.

[14] The polarizing film according to any one of [11] to [13], wherein the polarizing film has a length of 10 m or more.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the polarizing film which has at least 2 area|region with which the visibility correction polarization is different from each other can be provided.

1 is a schematic plan view showing an example of the polarizing film of the present invention.
2(a) to 2(e) are schematic cross-sectional views showing an example of the layer structure obtained in each step of the production process of the polarizing film of the present invention.
3(a) to 3(c) are schematic cross-sectional views each showing an example of the original polarizing plate of the present invention.

Hereinafter, a manufacturing method of the polarizing film of this invention and preferable embodiment of a polarizing film are demonstrated with reference to drawings. In addition, the scope of the present invention is not limited to the embodiments described herein, and various changes can be made without departing from the scope of the present invention.

[First Embodiment (Production Method of Polarizing Film and Polarizing Film)]

1 is a schematic plan view showing an example of the polarizing film of the present invention. 2(a) to 2(e) are schematic cross-sectional views showing a layer structure obtained in each step of the manufacturing process of the polarizing film shown in FIG. 1. Fig. 2(e) is an X-X sectional view of Fig. 1. The manufacturing method of the polarizing film 1 of this embodiment,

A preparation step of preparing a laminated film 62 (Fig. 2(b)) having a polarizing layer 11 containing a dichroic dye on at least one side of the base layer 13;

On the polarizing layer 11 of the laminated film 62, a protective layer 35 having a covering region 35a for covering the polarizing layer 11 and an exposed region 35b for exposing the polarizing layer 11 A protective layer lamination process to obtain a protective layer-forming laminated film 63 (FIG. 2(c)) by laminating,

Patterning with the patterned polarizing layer 11' formed by removing a partial region of the polarizing layer 11 by bringing the protective layer-forming laminated film 63 into contact with a dissolving solution capable of dissolving the polarizing layer 11 A solution contacting step of obtaining a polarizing layer forming film 64 (FIG. 2(d)),

It has a peeling step of peeling the protective layer 35 from the patterned polarizing layer forming film 64. Thereby, the polarizing film 1 which has the patterned polarizing layer 11' shown in FIG. 1 and FIG. 2(e), for example can be manufactured. The polarizing layer 11 may contain a liquid crystal compound, or a layer in which a polymerizable liquid crystal compound is aligned.

(Polarizing film)

An example of the polarizing film obtained by the above manufacturing method will be described. The polarizing film 1 shown in FIG. 1 is a film having a function of light absorption anisotropy and has a patterned polarizing layer 11'. The patterned polarizing layer 11' has a polarization region 11a and a low polarization region 11b having a lower visibility correction polarization degree Py than the polarization region 11a. The polarization region 11a contains a liquid crystal compound and a dichroic dye, and the visibility correction polarization degree is 90% or more. The low polarization region 11b does not contain a liquid crystal compound and a dichroic dye, and is preferably an opening of the patterned polarization layer 11'. The polarizing film 1 may have the patterned polarizing layer 11' on the base layer 13.

Although the polarizing film 1 has a patterned polarizing layer 11', in addition to the base layer 13 described above, the alignment layer 12, other layers, and the like may be further included. Details of the alignment layer 12 will be described later. As another layer, the surface protection layer formed for the purpose of protecting the surface of the patterned polarizing layer 11', etc. is mentioned, for example. When the polarizing film 1 has the base layer 13, it is preferable to form a surface protection layer on the surface opposite to the base layer 13 of the patterned polarizing layer 11', and the base layer 13 ), the surface protection layer may be formed on the surface of the patterned polarizing layer 11' on the side where the base layer 13 is peeled off. 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 from each other.

Moreover, in the polarizing film 1 shown in FIG. 2(e), although the example which has the orientation layer 12 and the patterned polarizing layer 11' on one side of the base layer 13 is shown, the base layer 13 ) May have an alignment layer and a patterned polarization layer on both sides. The structures of the patterned polarizing layers formed on both surfaces of the base layer 13 may be the same or different from each other.

The polarizing film 1 may be a long polarizing film having a length of 10 m or more, and in this case, the polarizing film 1 can be a wound body wound in a roll shape. The polarizing film can be continuously released from the wound body, and steps such as laminating with a retardation layer, which will be described later, and cutting with a sheet can be performed. The length of the long polarizing film used as a wound body is not particularly limited as long as it is 10 m or more, but can be, for example, 10000 m or less.

The polarization region 11a of the patterned polarization layer 11' may contain a liquid crystal compound and a dichroic dye. As for the polarization region 11a, the visibility correction polarization degree Py is preferably 90% or more, more preferably 92% or more, still more preferably 95% or more, and usually 100% or less. Moreover, as for the polarization region 11a, it is preferable to make the visibility correction simple substance transmittance (Ty) into 35% or more, for example, more preferably 40% or more, still more preferably 44% or more, and usually less than 50% to be.

It is preferable that the low polarization region 11b of the patterned polarization layer 11' does not contain a liquid crystal compound and a dichroic dye, it has a lower visibility correction polarization degree Py than the polarization region 11a, and the polarization region (11a) It is preferable to have a higher visibility correction simple substance transmittance (Ty). The visibility-corrected polarization degree Py of the low polarization region 11b can be, for example, 10% or less, preferably 5% or less, more preferably 1% or less, and may be 0%. Moreover, the visibility correction simple substance transmittance (Ty) of the low polarization region 11b can be 80% or more, for example, preferably 85% or more, more preferably 88% or more, and usually 98% or less .

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

Polarization degree [%] = {(T ₁ ― T ₂ ) / (T ₁ + T ₂ )} × 100 (Equation 1)

Simple substance transmittance [%] = (T ₁ + T ₂ )/2 (Equation 2)

The area occupied by the polarization region 11a and the area occupied by the low polarization region 11b may be appropriately selected depending on the characteristics required of the polarizing film 1. The total ratio of the area occupied by the polarizing region 11a and the low polarization region 11b to the surface area of the polarizing film 1 is preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more desirable. Moreover, with respect to the total area of the occupied area of the polarization region 11a and the occupied area of the low polarization region 11b, the occupied area of the polarization region 11a is preferably 50% or more, more preferably 70% or more. , More preferably 80% or more. For example, as shown in FIG. 1, the area occupied by the low polarization area 11b is smaller than the area occupied by the polarization area 11a, and the polarization area 11a may be formed to surround the low polarization area 11b. . In the polarizing film 1 shown in FIG. 1, although the polarization region 11a is formed so as to surround one circular low polarization region 11b, a plurality of low polarization regions 11b may be formed independently of each other.

Although the shape of the polarization region 11a and the shape of the low polarization region 11b are not particularly limited, for example, as shown in FIG. 1, the polarization region 11a is formed so as to surround the low polarization region 11b. In the case, the low polarization region 11b has a circular shape when viewed from a plane; Oval; Jang, Won-Hyung; Polygons such as triangles, squares, squares, and rhombuses; Character shape; It can be formed in any shape, such as a combination of these.

It is preferable that the shape of the low polarization region 11b is circular, elliptical, elliptical, or polygonal in plan view. When the low polarization region 11b is circular, the diameter is preferably 5 cm or less, more preferably 3 cm or less, and even more preferably 2 cm or less. When the low polarization region 11b is elliptical or elliptical, its long axis is preferably 5 cm or less, more preferably 3 cm or less, even more preferably 2 cm or less. When the low polarization region 11b is a polygon, the diameter of the virtual circle drawn so that the polygon is inscribed is preferably 5 cm or less, more preferably 3 cm or less, and even more preferably 2 cm or less. The low-polarization area 11b of the above-described shape can be suitably used as an area corresponding to the lens position of a camera formed on a smartphone or tablet. Since the low-polarization region 11b does not contain a liquid crystal compound and a dichroic dye, excellent transparency can be obtained, so that the performance of the camera can be improved.

Moreover, you may form the polarization region 11a and the low polarization region 11b so that the shape may become a shape, such as a linear shape, a strip shape, and a wavy shape, respectively, when viewed in plan. In this case, the polarization region 11a and the low polarization region 11b may be alternately formed in plurality. In this case, the widths of the polarization region 11a and the low polarization region 11b are each independently preferably 1 µm to 10 mm, more preferably 1 µm to 1 mm, and more preferably 1 µm to 100 µm. It is more preferable.

In addition, when the polarizing film is a long polarizing film, the long polarizing film is usually cut to a predetermined size according to the use of the polarizing film, and thus, the polarization region 11a or low polarization is at a predetermined position of the polarizing film after cutting. It is preferable to set the arrangement of the polarization region or the low polarization region in the long polarizing film so that the region 11b is formed. For example, when the polarizing film after cutting is the polarizing film 1 shown in FIG. 1, a plurality of low polarization areas 11b are formed at predetermined intervals in the longitudinal direction and/or the width direction of the elongated polarizing film. It is desirable to do.

The thickness of the polarization region 11a of the patterned polarizing layer 11' is preferably 0.5 µm or more, more preferably 1 µm or more, further preferably 5 µm or less, and more preferably 3 µm or less. Moreover, it is preferable that the thickness of the low polarization area 11b is less than 0.5 micrometer, and it is more preferable that it is 0 m. The thickness of the polarization region 11a and the low polarization region 11b can be measured by an interference film thickness meter, a laser microscope, or a stylus film thickness meter.

Next, each process of the manufacturing method of the polarizing film 1 is demonstrated based on FIGS. 2(a)-(e).

(Preparation process)

The laminated film 62 prepared in the preparation step is not particularly limited as long as it has a polarizing layer 11 on at least one side of the base layer 13, but as shown in Fig. 2(b), the base layer 13 It is preferable that the alignment layer 12 and the polarizing layer 11 are stacked in this order. The laminated film 62 is formed with an alignment layer forming step of coating the composition for forming an alignment layer on one surface of the substrate layer 13 to form an alignment layer 12 to obtain an alignment layer forming substrate layer 61. (FIG. 2(a)), a polarizing layer forming step of forming a polarizing layer 11 by coating a composition for forming a polarizing layer on the side of the alignment layer forming base layer 61 on which the alignment layer 12 is formed. Can be manufactured through.

(Base layer)

When manufacturing the polarizing film 1, the base layer 13 can be used to support the alignment layer 12 or the polarizing layer 11, and also the patterned polarizing layer 11 of the polarizing film 1 ') can be used to support.

Although the base material layer 13 may be a glass base material or a resin base material, it is preferable that it is 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 long resin base material wound in roll shape. It is preferable that a resin base material is a base material which has light transmittance which can transmit visible light. Here, the light transmittance means that the luminous intensity corrected simple substance transmittance is 80% or more with respect to light in the wavelength range of 380 to 780 nm.

The thickness of the base material layer 13 is preferably thin, from the viewpoint of being a mass capable of practical handling. However, when the thickness is too thin, the strength is lowered and the workability tends to be poor. The thickness of the base layer 13 is usually 5 µm to 300 µm, and preferably 20 µm to 200 µm. Moreover, the base material layer 13 may be formed so that peeling is possible, and, for example, the patterned polarizing layer 11' of the polarizing film 1 is bonded to a member constituting a display device, a retardation layer to be described later ( After ligating, what may peel off from the polarizing film 1 may be sufficient. Thereby, an additional thinning effect of the polarizing film 1 is obtained.

As resin which comprises a resin base material, For example, Polyolefin, 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 triacetyl cellulose, diacetyl cellulose and cellulose acetate propionate; Polyethylene naphthalate; Polycarbonate; Polysulfone; Polyether sulfone; Polyether ketone; Polyphenylene sulfide and polyphenylene oxide; And the like.

As a resin base material of a commercially available cellulose ester, "Fujitak film" (made by Fuji Photo Film Co., Ltd.); "KC8UX2M", "KC8UY" and "KC4UY" (above, manufactured by Konica Minolta Opto Corporation) and the like.

As a commercially available cyclic olefin resin, "Topas" (registered trademark) (manufactured by Ticona (Germany)), "Aton" (registered trademark) (manufactured by JSR Corporation), "ZEONOR" (registered trademark) , "ZEONEX" (registered trademark) (above, manufactured by Nippon Xeon Corporation) and "Apel" (registered trademark) (manufactured by Mitsui Chemicals Corporation). Such a cyclic olefin-based resin can be formed into a resin substrate by forming a film by known means such as a solvent casting method and a melt extrusion method. A commercially available cyclic olefin resin resin substrate can also be used. As a resin base material of a commercially available cyclic olefin resin, "Essina" (registered trademark), "SCA40" (registered trademark) (above, manufactured by Sekisui Chemical Industry Co., Ltd.), "Zeonoa film" (registered trademark) ( Optesse Co., Ltd.) and "Aton Film" (registered trademark) (JSR Co., Ltd.).

The base layer 13 may have a single-layer structure or a multi-layer structure of two or more layers. When the base layer 13 has a multi-layer structure, each layer may be formed of the same material or may be formed of different materials from each other.

Moreover, the base material layer 13 may have a 1/4 wavelength plate function. When the base layer 13 has a 1/4 wavelength plate function, a polarizing film having the function of an original polarizing plate can be obtained by combining the base layer 13 and the patterned polarizing layer 11'. Thus, the original polarizing plate can be obtained without attaching the phase difference layer having the function of a quarter wave plate to the polarizing film 1 separately from the base layer 13. When the base layer 13 has a multi-layer structure, a patterned polarizing layer 11' is formed by using a layer having a 1/2 wavelength plate function and a layer having a 1/4 wavelength plate function stacked. A circular polarizing plate can be obtained by laminating on the layer side having the function of a two-wavelength plate. Alternatively, when the base layer 13 has a multi-layer structure, a circular polarizing plate can be obtained also by using a layer having a layer having a 1/4 wavelength plate function of reverse wavelength dispersion and a layer having a positive C plate function.

(Polarization layer)

The polarizing layer 11 is not particularly limited as long as it contains a dichroic dye, but preferably has a region containing a liquid crystal compound and a dichroic dye. When the polarizing layer 11 has the polarization property of the polarizing film 1 plane, it is preferable to have a region in which the dichroic dye and liquid crystal compound are horizontally aligned with respect to the polarizing film 1 plane. Moreover, when the polarizing layer 11 has the polarization characteristic of the film thickness direction of the polarizing film 1, it is preferable to have the area|region in which the dichroic dye and liquid crystal compound are horizontally aligned with respect to the plane of the polarizing film (1). .

In the polarizing layer 11, the region in which the dichroic dye and the liquid crystal compound are horizontally aligned with respect to the plane of the polarizing film 1, absorbance in the horizontal direction of the liquid crystal alignment with respect to light having a wavelength of λ nm A1 (λ) and liquid crystal alignment The dichroic ratio (= A1 (λ)/A2 (λ)), which is the ratio of absorbance A2 (λ) in the vertical direction in the plane, is preferably 7 or more, more preferably 20 or more, and even more preferably 30 or more. It shows that it has a polarization property excellent in absorption selectivity, so that this value is high. Although different depending on the type of the dichroic dye, when the polarizing layer 11 is a nematic liquid crystal phase, the ratio is about 5 to 10. In addition, when the polarizing layer 11 is a nematic liquid crystal phase and a smectic liquid crystal phase, the liquid crystal compound and the dichroic dye are not phase-separated, for example, surface observation by various microscopes or scattering degree measurement by a haze meter. Can be confirmed by

The thickness of the polarizing layer 11 is preferably 0.5 µm or more, more preferably 1 µm or more, further preferably 10 µm or less, and more preferably 5 µm or less. The thickness of the polarizing layer 11 can be measured with an interference film thickness meter, a laser microscope, or a tactile film thickness meter.

(Alignment layer formation process)

In the alignment layer forming step, the alignment layer forming composition is coated on one surface of the base layer 13 to form the alignment layer 12 to obtain the alignment layer forming base layer 61 (Fig. 2(a)). The alignment layer 12 formed in the alignment layer forming step may have an alignment regulating force to align the liquid crystal compound laminated thereon in a desired direction. As the composition for forming an alignment layer, an alignment polymer composition described later, a composition for forming a photo-alignment film, a composition including a resin material for forming a groove alignment film, or the like can be used.

The alignment layer 12 facilitates liquid crystal alignment of the liquid crystal compound. The state of liquid crystal alignment, such as horizontal alignment, vertical alignment, hybrid alignment, and oblique alignment, varies depending on the properties of the alignment layer 12 and the liquid crystal compound, and the combination can be arbitrarily selected. For example, if the alignment layer 12 is a material that expresses horizontal alignment as an alignment regulating force, the liquid crystal compound can form a horizontal alignment or hybrid alignment, and if the alignment layer 12 is a material that expresses vertical alignment, the liquid crystal The compound may form a vertical or oblique orientation. The expressions such as horizontal and vertical indicate the direction of the long axis of the oriented liquid crystal compound when the polarizing film (1) is the reference plane. For example, vertical alignment means having a long axis of the polymerizable liquid crystal aligned in a direction perpendicular to the plane of the polarizing film (1). The vertical term here means 90° ± 20° with respect to the polarizing film (1) plane. Since it is preferable that the polarizing film 1 has the polarization property of the polarizing film 1 plane, it is preferable to form the alignment layer 12 using the material which expresses a horizontal orientation.

The orientation regulating force of the alignment layer 12 can be arbitrarily adjusted according to the surface condition or rubbing conditions when the alignment layer 12 is formed from an alignment polymer, and when it is formed from a photo-alignment polymer, polarization It can be arbitrarily adjusted according to irradiation conditions and the like. Moreover, liquid crystal alignment can also be controlled by selecting physical properties, such as surface tension and liquid crystallinity, of a 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. Moreover, the alignment layer 12 formed between the base layer 13 and the polarization layer 11 is insoluble in the solvent used when forming the polarization layer 11 on the alignment layer 12, and is also a solvent. It is preferable to have heat resistance in the heat treatment for removal of and alignment of liquid crystals.

Examples of the alignment layer 12 include an alignment film made of an alignment polymer, a photo alignment film, or a groove alignment film. When the base material layer 13 is unwound from a wound body in which a long resin base material is wound, it is preferable that the alignment layer 12 is a photo-alignment film because the orientation direction can be easily controlled.

Examples of the oriented polymer include polyamide or gelatin having an amide bond in the molecule, polyimide having an imide bond in the molecule, polyamic acid which is a hydrolyzate thereof, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, and polyoxa And sol, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid, or polyacrylic acid esters. Especially, polyvinyl alcohol is preferable. These oriented polymers may be used alone or in combination of two or more.

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

As a solvent used for an oriented polymer composition, water; Alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, methyl cellosolve, butyl cellosolve or propylene glycol monomethyl ether; Ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl 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; Aliphatic hydrocarbon solvents such as pentane, hexane or heptane; Aromatic hydrocarbon solvents such as toluene or xylene, nitrile solvents such as acetonitrile; Ether solvents such as tetrahydrofuran or dimethoxyethane; Chlorine-substituted hydrocarbon solvents such as chloroform or chlorobenzene; And the like. These solvents may be used alone or in combination of two or more.

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

As the alignment polymer composition, a commercially available alignment film material may be used as it is. Examples of commercially available alignment film materials include San-Eva (registered trademark) (manufactured by Nissan Chemical Industries) or Optomer (registered trademark) (manufactured by JSR Corporation).

As a method of applying the oriented polymer composition to the base layer 13, a coating method such as a spin coating method, an extrusion method, a gravure coating method, a die coating method, a bar coating method or an applicator method, or a printing method such as a flexo method And well-known methods. When the polarizing film 1 is manufactured by a continuous production method of a roll-to-roll type, 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 oriented polymer composition, a dry film of the oriented polymer is formed. Examples of the solvent removal method include a natural drying method, a ventilation drying method, a heating drying method, and a vacuum drying method. Thereafter, the dried film can be brought into contact with a rotating rubbing roll wound with a rubbing cloth to form an alignment layer 12.

The photo-alignment film is usually for an alignment layer formed by coating a base material layer 13 with a composition (hereinafter, sometimes referred to as "a composition for forming a photo-alignment film") containing a polymer or monomer having a photoreactive group and a solvent. It can be obtained by irradiating the coating layer with polarized light (preferably polarized UV). The photo-alignment film is more preferable in that the direction of the orientation regulating 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 causes liquid crystal alignment ability by irradiating light. Specifically, it causes the photoreaction which is the origin of the liquid crystal alignment ability, such as causing the orientation of the molecules generated by irradiation of light or isomerization reaction, dimerization reaction, photocrosslinking reaction, or photolysis reaction. Among the photoreactive groups, it is preferable to cause a dimerization reaction or a photocrosslinking reaction from the viewpoint of excellent orientation. As the photoreactive group capable of causing the above reaction, it is preferable to have an unsaturated bond, particularly a double bond, and a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond (C=N bond), nitrogen A group having at least one selected from the group consisting of a nitrogen double bond (N=N bond) and a carbon-oxygen double bond (C=O bond) is more preferable.

Examples of the photoreactive group having a C=C bond include vinyl group, polyene group, stilbene group, stilazole group, stilbazolium group, chalcone group, or cinnamoyl group. It is preferable that it is a chalcone group or a cinnamoyl group from a viewpoint of easy control of reactivity or the expression of the orientation regulating force at the time of light alignment. Examples of the photoreactive group having a C=N bond include a group having a structure such as an aromatic sheep 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 those having azoxybenzene as a basic structure. Examples of the photoreactive group having a C=O bond include a benzophenone group, a coumarin group, an anthraquinone group, or a maleimide group. These groups may have substituents such as alkyl groups, alkoxy groups, aryl groups, allyloxy groups, cyano groups, alkoxycarbonyl groups, hydroxyl groups, sulfonic acid groups or halogenated alkyl groups.

As a solvent for the composition for forming a photo-alignment film, it is preferable to dissolve a polymer and a monomer having a photoreactive group, and examples of the solvent include, for example, a solvent exemplified as a solvent for the above-mentioned alignment polymer composition.

The content of the polymer or monomer having a photo-reactive group in the composition for forming a photo-alignment film can be appropriately adjusted depending on the type of the polymer or monomer having the photo-reactive group or the thickness of the photo-alignment film to be produced. It is preferable, and the range of 0.3-10 mass% is especially preferable. Moreover, in the range in which the properties of the photo-alignment film are not significantly impaired, a polymer material such as polyvinyl alcohol or polyimide or a photosensitizer may be included.

As a method of coating the composition for forming a photo-alignment film on the base layer 13, the same method as the method of coating the above-described alignment polymer composition on the base layer 13 can be mentioned. As a method of removing a solvent from the coating composition for forming a photo-alignment film, the method similar to the method of removing a solvent from an oriented polymer composition is mentioned, for example.

The polarization irradiation may be performed directly from the dry film obtained by removing the solvent from the composition for forming a photo-alignment film coated on the substrate layer 13, and the substrate layer 13 is such that polarized light transmitted through the substrate layer 13 is irradiated to the dry film. ). Moreover, it is especially preferable that the polarization used for the polarization irradiation is substantially parallel light. The wavelength of the polarized light to be irradiated is preferably a wavelength range in which a photoreactive group of a polymer or a monomer having a photoreactive group can absorb light energy. Specifically, UV (ultraviolet light) in the wavelength range of 250 to 400 nm is particularly preferable. Examples of light sources used for polarization irradiation include xenon lamps, high pressure mercury lamps, ultra high pressure mercury lamps, metal halide lamps, ultraviolet light lasers such as KrF and ArF, and high pressure mercury lamps, ultra high pressure mercury lamps or metal halide lamps. It is more preferable. These lamps are preferable because the emission intensity of ultraviolet light having a wavelength of 313 nm is large. Polarization can be irradiated by irradiating light from a light source through an appropriate polarizer. As such a polarizer, a polarizing prism such as a polarizing filter, a Glen Thompson, a Glen Taylor, or a wire grid type polarizer can be used.

Moreover, when performing rubbing or polarization irradiation, if masking is performed, it is also possible to form a plurality of regions (patterns) with different directions of liquid crystal alignment.

A groove alignment film is a film having an uneven pattern or a plurality of grooves (grooves) on the film surface. When liquid crystal molecules are placed on a film having a plurality of linear grooves arranged at equal intervals, the liquid crystal molecules are aligned in a direction along the groove.

As a method of obtaining a groove alignment film, after exposure through a photosensitive polyimide film surface with an exposure mask having a pattern-shaped slit, a developing and rinsing treatment is performed to form an uneven pattern, a plate-shaped disk having grooves on the surface E., a method of forming a layer of a UV curable resin before curing, transferring the resin layer to the substrate, and curing the film, and pressing the roll-shaped disk having a plurality of grooves on the film of the UV curable resin before curing formed on the substrate to unevenness And forming and then curing. Specifically, the methods described in JP-A-6-34976 and JP-A-2011-242743 are mentioned.

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

(Polarizing layer formation process)

In the polarizing layer forming step, the polarizing layer 11 is formed by coating a composition for forming a polarizing layer on the side of the alignment layer forming base layer 61 on which the alignment layer 12 is 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 may contain a sensitizer, a polymerization inhibitor, a leveling agent, a reactive additive, and the like.

(Liquid Crystal Compound)

As a liquid crystal compound contained in the composition for forming a polarizing layer, a known liquid crystal compound can be used. The type of the liquid crystal compound is not particularly limited, and rod-like liquid crystal compounds, disc-like liquid crystal compounds, and mixtures thereof can be used. Moreover, the liquid crystal compound may be a polymer liquid crystal compound, a polymerizable liquid crystal compound, or a mixture of these.

As the liquid crystal compound, it is preferable to use a polymerizable liquid crystal compound. By using a polymerizable liquid crystal compound, the color of the polarizing film can be arbitrarily controlled, and the polarizing film can be significantly thinned. Moreover, since a polarizing film can be manufactured without performing an extending|stretching process, it can be set as a non-stretchable polarizing film which has no 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, a photopolymerizable group means a group that can be involved in a polymerization reaction by an active radical or an acid 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, oxylanyl group, and oxetanyl group. . Especially, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxylanyl group, and an oxetanyl group are preferable, and an acryloyloxy group is more preferable. The liquid crystal property may be a thermotropic liquid crystal or a lyotropic liquid crystal, but when mixing with the dichroic dye as in the polarizing layer 11 of this embodiment, it is preferable to use a thermotropic liquid crystal.

When the polymerizable liquid crystal compound is a thermotropic liquid crystal, a thermotropic liquid crystal compound showing a nematic liquid crystal phase may be used, or a thermotropic liquid crystal compound showing a smectic liquid crystal phase may be used. The liquid crystal state represented by the polymerizable liquid crystal compound is preferably a smectic phase, and more preferably a higher order smectic phase from the viewpoint of high performance. Among them, Smectic B phase, Smectic D phase, Smectic E phase, Smectic F phase, Smectic G phase, Smectic H phase, Smectic I phase, Smectic J phase, Smectic K phase or Smectic The higher order smectic liquid crystal compound forming the L phase is more preferable, and the higher order smectic liquid crystal compound forming the smectic B phase, smectic F phase or smectic I phase is more preferable. If the polarizing layer 11 formed by the polymerizable liquid crystal compound is these higher order smectic phases, a region with higher polarization performance can be formed in the polarizing layer 11. Moreover, in such a region with high polarization performance, in the X-ray diffraction measurement, a Bragg peak derived from a higher order structure such as a hexatic phase or a crystal phase is obtained. The Bragg peak is a peak derived from a molecularly oriented periodic structure, and a film having a periodic interval of 3 to 6 Å can be obtained. In the polarizing film 1 of this embodiment, since the polarizing layer 11 contains a polymer in which the polymerizable liquid crystal compound is polymerized in a smectic state, the polarizing layer 11 can be provided with higher polarizing properties. desirable.

Whether 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 forming the coating film by applying the composition for forming a polarizing film to the substrate, the solvent contained in the coating film is removed by heat treatment under conditions where the polymerizable liquid crystal compound does not polymerize. Subsequently, the liquid crystal phase expressed by heating the coating film formed on the substrate to an isotropic temperature and gradually cooling is inspected by texture observation with a polarization microscope, X-ray diffraction measurement, or differential scanning calorimetry.

As such a polymerizable liquid crystal compound, specifically, 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 formula (A), X ¹ , X ² and X ³ each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group, wherein the divalent aromatic group or a divalent alicyclic hydrocarbon group is included The hydrogen atom may be substituted with 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, a cyano group or a nitro group, and a divalent aromatic group or a divalent alicyclic group The carbon atom constituting the formula hydrocarbon group may be substituted with an oxygen atom, a sulfur atom, or a nitrogen atom. However, at least 1 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.

Y ¹ , Y ² , W ¹ and W ² are, independently of each other, 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-, -S- or NH- May be substituted with.

U ¹ and U ² represent, independently of each other, a polymerizable group or a hydrogen atom, and at least one is a polymerizable group.] Compounds (hereinafter, sometimes referred to as compounds (A)) and the like can be given. .

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 a cyclohexane-1,4-diyl group which may have a substituent. . 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 a trans-cyclohexane-1,4-diyl group. It is more preferable. When the structure of the trans-cyclohexane-1,4-diyl group is included, there is a tendency that the smectic liquid crystallinity is easily expressed. Moreover, as the substituent optionally having a 1,4-phenylene group which may have a substituent and a cyclohexane-1,4-diyl group which may have a substituent, an alkyl group having 1 to 4 carbon atoms such as methyl group, ethyl group or butyl group, And halogen atoms such as a cyano group, a chlorine atom or a fluorine atom. It is preferably unsubstituted.

Y ¹ and Y ² are, independently of each other, a single bond, -CH ₂ CH ₂ -, -CH ₂ O-, -COO-, -OCO-, -N=N-, -CR ^a =CR ^b -,- C≡C- or CR ^a =N- is preferable, and R ^a and R ^b independently of each other 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 preferable that Y ¹ and Y ² are different bonding methods. When Y ¹ and Y ² are mutually different bonding methods, there is a tendency for the smectic liquid crystal properties to be easily exhibited.

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

As the alkanediyl group having 1 to 20 carbon atoms represented by V ¹ and V ² , a methylene group, an ethylene group, a propane-1,3-diyl group, butane-1,3-diyl group, 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, decan-1,10-diyl group, tetradecane-1 And a 14-diyl group or icosane-1,20-diyl group. V ¹ and V ² are preferably an alkanediyl group having 2 to 12 carbon atoms, and more preferably a linear alkanediyl group having 6 to 12 carbon atoms. Crystallinity improves by having a linear alkanediyl group having 6 to 12 carbon atoms, and there is a tendency to easily exhibit smectic liquid crystallinity.

As the substituent optionally having an alkanediyl group having 1 to 20 carbon atoms which may have a substituent, a cyano group, a halogen atom such as a chlorine atom or a fluorine atom, etc. may be mentioned, but the alkanediyl group is preferably unsubstituted, It is more preferable that it is unsubstituted and also a linear alkanediyl group.

U ¹ and U ² are preferably a polymerizable group together, and more preferably a photopolymerizable group together. Since the polymerizable liquid crystal compound having a photopolymerizable group can polymerize under a lower temperature condition than a thermal polymerizable group, it is advantageous in that a polymer of the polymerizable liquid crystal compound can be formed in a high order 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, oxylanyl group, and oxetanyl group. . Especially, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxylanyl group, or an oxetanyl group is preferable, and a methacryloyloxy group or an acryloyloxy group is more preferable.

As such a polymerizable liquid crystal compound, the following are mentioned, for example.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

Among the exemplified compounds, formula (1-2), formula (1-3), formula (1-4), formula (1-6), formula (1-7), formula (1-8), formula ( 1-13), at least 1 member selected from the group which consists of a compound represented by Formula (1-14) and Formula (1-15) is preferable.

The illustrated compound (A) can be used alone or in combination for the polarizing layer (11). Moreover, when combining 2 or more types of polymerizable liquid crystal compounds, it is preferable that at least 1 type is compound (A), and it is more preferable that 2 or more types are compound (A). By combining two or more types of polymerizable liquid crystal compounds, there are cases in which liquid crystallinity can be temporarily maintained even at a temperature below the liquid crystal-crystalline phase transition temperature. The mixing ratio in the case of combining two types of polymerizable liquid crystal compounds is usually 1:99 to 50:50, preferably 5:95 to 50:50, and more preferably 10:90 to 50:50. Do.

Compound (A) is, for example, Lub et al. Recl. Trav. Chim. It can be produced by a known method described in Pays-Bas, 115, 321-328 (1996), or Japanese Patent Publication No. 4719156.

The content of the polymerizable liquid crystal compound in the polarizing layer 11 is usually 50 to 99.5 parts by mass, preferably 60 to 99 parts by mass, more preferably 100 parts by mass of the solid content of the polarizing layer 11 Preferably it is 70-98 mass parts, More preferably, it is 80-97 mass parts. When the content of the polymerizable liquid crystal compound is within the above range, alignment tends to be high. Here, solid content means the total amount of the component which removed the solvent from the composition for polarizing layer formation mentioned later.

(Dichroic pigment)

The dichroic dye refers to a dye having a property that absorbs in the long axis direction of the molecule and absorbance in the short axis direction. The dichroic dye is a dye that is aligned with a liquid crystal compound and exhibits dichroism, and the dichroic dye itself may have polymerizability or may have liquid crystallinity. As a dichroic dye, it is preferable to have the property of absorbing visible light, and it is more preferable to have the absorption maximum wavelength (λ _MAX ) in the range of 380-680 nm. Examples of such dichroic dyes include acridine dyes, oxazine dyes, cyanine dyes, naphthalene dyes, azo dyes or anthraquinone dyes, and azo dyes are particularly preferred. Examples of the azo pigment include monoazo pigments, biszo pigments, triszo pigments, tetrakiszo pigments, stilbenazo pigments, and the like, preferably biszo pigments or triszo pigments. The dichroic dyes may be used alone or in combination of two or more, but in order to obtain absorption in all of visible light, it is preferable to combine three or more dichroic dyes, and combining three or more azo dyes It is more preferable.

As an azo pigment, for example, Formula (I)

T ¹ -A ¹ (-N=NA ² ) _p -N=NA ³ -T ² (I)

[In formula (I), A ¹ , A ² and A ³ independently of each other may have a 1,4-phenylene group, naphthalene-1,4-diyl group, or 2 which may have a substituent. Represents a pseudo heterocyclic group, T ¹ and T ² are, independently of each other, an electron withdrawing group or an electron emitting group, and are located at a position substantially 180° with respect to the azo bond surface. p represents the integer of 0-4. When p is 2 or more, each A ² may be the same as or different from each other. The -N=N- bond may be substituted with -C=C-, -COO-, -NHCO- or -N=CH- bond in the range showing absorption in the visible region.]

And a compound represented by (hereinafter, sometimes referred to as “compound (I)”).

Substituents optionally having 1,4-phenylene group, naphthalene-1,4-diyl group and divalent heterocyclic group in A ¹ , A ² and A ³ include 1 to 4 carbon atoms such as methyl group, ethyl group or butyl group. Alkyl group of; Alkoxy groups having 1 to 4 carbon atoms such as methoxy group, ethoxy group or butoxy group; Alkyl groups having 1 to 4 carbon atoms, such as trifluoromethyl group; Cyano group; Nitro group; Halogen atoms such as chlorine atom and fluorine atom; Substituted or unsubstituted amino groups such as amino groups, diethylamino groups and pyrrolidino groups (Substituted amino groups are amino groups having one or two alkyl groups having 1 to 6 carbon atoms, or two substituted alkyl groups bonded to each other to have 2 to 8 carbon atoms. means of the amino group which forms an alkanediyl group. unsubstituted amino group, may be mentioned is -NH _2.). Moreover, a methyl group, an ethyl group, a hexyl group, etc. are mentioned as a C1-C6 alkyl 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, or octane-1,8-diyl group. In order to contain the compound (I) in a high-order liquid crystal structure such as a smectic liquid crystal, A ¹ , A ² and A ³ are, independently of each other, unsubstituted, 1,4-phenyl in which hydrogen is substituted with a methyl group or a methoxy group. A ren group or a divalent heterocyclic group is preferable, and p is preferably 0 or 1. Among them, p is 1, and it is more preferable that at least two of the three structures of A ¹ , A ² and A ³ are 1,4-phenylene groups in terms of both simplicity of molecular synthesis and high performance. .

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

T ¹ and T ² are, independently of each other, an electron withdrawing group or an electron emitter, preferably having different structures, T ¹ is an electron withdrawing group, T ² is an electron emitter, or T ¹ is an electron emitter and T ² is an electron. It is more preferable that it is an aspirator. Specifically, T ¹ and T ² are, independently of each other, 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 amino group having 1 or 2 alkyl groups having 1 to 6 carbon atoms, Or, it is preferable that it is an amino group or a trifluoromethyl group in which two substituted alkyl groups are bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms, and among them, in order to be contained in a high-order liquid crystal structure such as a smectic liquid crystal, a molecule is used. Since it needs to be a structure having a smaller exclusion volume, 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 two substitutions Amino groups in which alkyl groups are bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms are preferred.

As such an azo dye, the following are mentioned, for example.

[Formula 5]

[Formula 6]

[In formulas (2-1) to (2-6), B ¹ to B ²⁰ are, independently of each other, a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a nitro group, It represents a substituted or unsubstituted amino group (the definitions of a substituted amino group and an unsubstituted amino group are 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 hydrogen atoms or methyl groups, and more preferably hydrogen atoms.

n1-n4 respectively independently represent the integer of 0-3.

When n1 is 2 or more, a plurality of B ² may be the same or different, respectively,

When n2 is 2 or more, a plurality of B ^{6 s} may be the same or different, respectively,

When n3 is 2 or more, a plurality of B ⁹ may be the same or different, respectively,

When n4 is 2 or more, a plurality of B ¹⁴ may be the same or different.

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

[Formula 7]

[In the formula (2-7), R ¹ to R ⁸ each 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.]

As said oxazine dye, the compound represented by Formula (2-8) is preferable.

[Formula 8]

[In the formula (2-8), R ⁹ to R ¹⁵ each 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.]

As said acridine dye, the compound represented by Formula (2-9) is preferable.

[Formula 9]

[In the formula (2-9), R ¹⁶ to R ²³ each 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.]

In the formulas (2-7), (2-8) and (2-9), the alkyl group having 1 to 4 carbon atoms represented by R ^x is a methyl group, ethyl group, propyl group, butyl group, pentyl group or Hexyl group etc. are mentioned, As a C6-C12 aryl group, a phenyl group, a toluyl group, a xylyl group, or a naphthyl group etc. are mentioned.

As said cyanine dye, the compound represented by Formula (2-10) and the compound represented by Formula (2-11) are preferable.

[Formula 10]

[In formula (2-10), D ¹ and D ² independently represent groups represented by any of formulas (2-10a) to (2-10d).

[Formula 11]

n5 represents the integer of 1-3.]

[Formula 12]

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

[Formula 13]

n6 represents the integer of 1-3.]

The content of the dichroic dye (when multiple species are included, the total amount thereof) is usually 0.1 to 30 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound in the polarizing layer 11 from the viewpoint of obtaining good light absorption properties. It is preferable, more preferably 1 to 20 parts by mass, and still more preferably 3 to 15 parts by mass. When the content of the dichroic dye is less than this range, light absorption becomes insufficient, and sufficient polarization performance is not obtained, and if it is more than this range, alignment of the liquid crystal molecules may be inhibited.

(solvent)

The composition for forming a polarizing layer may contain a solvent. In general, since the polymerizable liquid crystal compound has a high viscosity, when a 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 consequently, the polarizing layer 11 is used. It becomes easy to form. As a solvent, it is preferable that a polymerizable liquid crystal compound and a dichroic dye can be dissolved completely, and it is preferable that it is a solvent inert to the polymerization reaction of a polymerizable liquid crystal compound.

Examples of the solvent include 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; Ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone or propylene glycol methyl ether acetate or ethyl lactate; Ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone; Aliphatic hydrocarbon solvents such as pentane, hexane or heptane; Aromatic hydrocarbon solvents such as toluene or xylene, nitrile solvents such as acetonitrile; Ether solvents such as tetrahydrofuran or dimethoxyethane; Chlorine-containing solvents such as chloroform or chlorobenzene; And amide solvents such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone. 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 relative 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, since the viscosity of the composition for forming a polarizing layer is lowered, the thickness of the polarizing layer 11 is approximately uniform, and there is a tendency that non-uniformity is less likely to occur in the polarizing layer 11. Moreover, content of such a solid content can be determined considering the thickness of the polarizing layer 11 to be manufactured.

(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 such as a polymerizable liquid crystal compound. As the polymerization initiator, from the viewpoint of not depending on the phase state of the thermotropic liquid crystal, a photo polymerization initiator that generates active radicals by the action of light is preferable.

Examples of the polymerization initiator include benzoin compounds, benzophenone compounds, alkylphenone compounds, acylphosphine oxide compounds, triazine compounds, iodonium salts, or 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'-methyldiphenylsulfide, 3,3',4,4'-tetra( tert-butylperoxycarbonyl)benzophenone and 2,4,6-trimethylbenzophenone.

Examples of the alkylphenone compound include diethoxyacetophenone, 2-methyl-2-morpholino-1-(4-methylthiophenyl)propan-1-one, and 2-benzyl-2-dimethylamino-1 -(4-morpholinophenyl)butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1,2-diphenyl-2,2-dimethoxyethan-1- On, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]propan-1-one, 1-hydroxycyclohexylphenylketone or 2-hydroxy-2-methyl- And oligomers of 1-[4-(1-methylvinyl)phenyl]propan-1-one.

Examples of acylphosphine oxide compounds include 2,4,6-trimethylbenzoyldiphenylphosphine oxide or bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

As the triazine compound, for example, 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4-bis(trichloromethyl) -6-(4-methoxynaphthyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-tri Azine, 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(trichloromethyl)-6-[2-(3,4-dimethoxyphenyl)ethenyl]-1,3, 5-triazine and the like.

A polymerization initiator can also use what is marketed. As a commercially available polymerization initiator, Irgacure (registered trademark) 907, 184, 651, 819, 250, 369, 379, 127, 754, OXE01, OXE02, or OXE03 (manufactured by Chiba Specialty Chemicals Co., Ltd.) ); Shakeall (registered trademark) BZ, Z, or BEE (manufactured by Seiko Chemical Co., Ltd.); Kayacure (registered trademark) BP100, or UVI-6992 (manufactured by Dow Chemical Co., Ltd.); Adeka Optomer SP-152, N-1717, N-1919, SP-170, Adeka Acles NCI-831, Adeka Acles NCI-930 (manufactured by ADEKA Corporation); TAZ-A or TAZ-PP (manufactured by Siebel Hegner Co., Ltd.); TAZ-104 (manufactured by Sanwa Chemical Co., Ltd.); And the like. One type of polymerization initiator in the composition for forming a polarizing layer may be used, or two or more types of polymerization initiators may be mixed and used in accordance with the light source of light.

The content of the polymerization initiator in the composition for forming a polarizing layer can be appropriately adjusted depending on the type and amount of the polymerizable liquid crystal compound, but is usually 0.1 to 30 parts by mass, preferably 100 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound. Is 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass. When the content of the polymerization initiator is within the above range, polymerization can be carried out 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 the liquid crystal compound, and when a polymerizable liquid crystal compound having a photopolymerizable group is used, the sensitizer is preferably a photosensitizer. Examples of the sensitizer include xanthone compounds such as xanthone and thioxanthone (eg, 2,4-diethylthioxanthone, 2-isopropylthioxanthone); Anthracene compounds such as anthracene and an alkoxy group-containing anthracene (for example, dibutoxyanthracene); 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 even more preferably 0.5 to 3 parts by mass, relative to 100 parts by mass of the content of the polymerizable liquid crystal compound.

(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 progress of the polymerization reaction of the polymerizable liquid crystal compound can be controlled by the polymerization inhibitor.

Examples of the polymerization inhibitor include hydroquinone, hydroxy group-containing hydroquinone, alkoxy group-containing catechol (for example, butyl catechol, etc.), pyrogallol, 2,2,6,6-tetramethyl-1-pipe Radical scavengers such as lidinyloxy radicals; Thiophenols; and 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 0.5 to 5 parts by mass relative to 100 parts by mass of the content of the polymerizable liquid crystal compound. Parts, more preferably 0.5 to 3 parts by mass. If the content of the polymerization inhibitor is within the above range, polymerization can be carried out 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 fluidity of the composition and making the film obtained by coating the composition more flat, for example, an organic modified silicone oil-based, polyacrylate-based or perfluoroalkyl-based leveling agent Can be mentioned. Specifically, DC3PA, SH7PA, DC11PA, SH28PA, SH29PA, SH30PA, ST80PA, ST86PA, SH8400, SH8700, FZ2123 (all manufactured by Toray Dow Corning Co., Ltd.), KP321, KP323, KP324, KP326, KP340, KP341 , X22-161A, KF6001 (above, all manufactured by Shin-Etsu Chemical Industry Co., Ltd.), TSF400, TSF401, TSF410, TSF4300, TSF4440, TSF4445, TSF-4446, TSF4452, TSF4460 (both above, all Momentive Performance Materials Japan joint ventures) Manufactured), fluorinert (registered trademark) FC-72, copper FC-40, copper FC-43, copper FC-3283 (above, manufactured by Sumitomo 3M Co., Ltd.), Megapak (registered) Trademarks) R-08, Copper R-30, Copper R-90, Copper F-410, Copper F-411, Copper F-443, Copper F-445, Copper F-470, Copper F-477, Copper F-479 , Copper F-482, Copper F-483 (above, all manufactured by DIC Corporation), F-top (brand name) EF301, Copper EF303, Copper EF351, Copper EF352 (above, all manufactured by Mitsubishi Material Electronics Hwasung Co., Ltd.), Suplon (registered trademark) S-381, copper S-382, copper S-383, copper S-393, copper SC-101, copper SC-105, KH-40, SA-100 (above, all AGC Semi Chemical Manufactured by Co., Ltd.), trade names E1830, Dong E5844 (manufactured by Daikin Fine Chemical Research Institute), BM-1000, BM-1100, BYK-352, BYK-353 or BYK-361N (all trade names: manufactured by BM Chemie ) And the like. Especially, a polyacrylate leveling agent or a perfluoroalkyl leveling agent is 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 even more preferably 0.1 to 3 parts by mass with respect to 100 parts by mass of the liquid crystal compound. . When the content of the leveling agent is within the above range, it is easy to horizontally align the liquid crystal compound, and the resulting polarizing layer tends to be smoother. When the content of the leveling agent in the liquid crystal compound exceeds the above range, unevenness tends to occur easily in the polarizing layer obtained. Moreover, the composition for polarizing layer formation may contain 2 or more types of leveling agents.

(Reactive additives)

The composition for forming a polarizing layer may contain a reactive additive. As a reactive additive, it is preferable to have a carbon-carbon unsaturated bond and an active hydrogen reactive group in the molecule. In addition, the term "active hydrogen reactive group" as used herein means a group having reactivity with a group having an active hydrogen such as a carboxyl group (-COOH), hydroxyl group (-OH), amino group (-NH ₂ ), glycidyl group, oxa A typical example is a sleepy group, carbodiimide group, aziridine group, imide group, isocyanate group, thioisocyanate group, maleic anhydride group and the like. The number of carbon-carbon unsaturated bonds or active hydrogen reactive groups possessed by the reactive additive is usually 1 to 20, respectively, and preferably 1 to 10, respectively.

In the reactive additive, it is preferable that at least two active hydrogen reactive groups are present, and in this case, a plurality of active hydrogen reactive groups may be the same or different.

The carbon-carbon unsaturated bond of 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. Especially, as a reactive additive, it is preferable to contain a carbon-carbon unsaturated bond as a vinyl group and/or (meth)acrylic group. Moreover, the reactive additive which is at least 1 sort(s) selected from the group which consists of an epoxy group, a glycidyl group, and an isocyanate group is preferable, and the reactive additive which has an acrylic group and an isocyanate group is more preferable.

Specific examples of the reactive additives include compounds having a (meth)acrylic group and an epoxy group, such as methacryloxyglycidyl ether and acryloxyglycidyl ether; Compounds having an (meth)acrylic group and an oxetane group, such as oxetane acrylate and oxetane methacrylate; Compounds having a (meth)acrylic group and a lactone group, such as lactone acrylate and lactone methacrylate; Compounds having a vinyl group and an oxazoline group, such as vinyl oxazoline and isopropenyl oxazoline; And oligomers of compounds having (meth)acrylic groups and isocyanate groups, such as isocyanatomethylacrylate, isocyanatomethylmethacrylate, 2-isocyanatoethylacrylate or 2-isocyanatoethylmethacrylate. Can. Moreover, the compound etc. which have vinyl groups, vinylene groups, and acid anhydrides, such as methacrylic anhydride, acrylic anhydride, maleic anhydride, or vinyl maleic anhydride, etc. are mentioned. Among them, methacryloxyglycidyl ether, acryloxyglycidyl ether, isocyanatomethyl acrylate, isocyanatomethyl methacrylate, vinyloxazoline, 2-isocyanatoethyl acrylate, 2-isocyanatoethyl Methacrylates or oligomers above are preferred, and isocyanatomethylacrylate, 2-isocyanatoethylacrylate or oligomers above are particularly preferred.

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

[Formula 14]

[In the formula (Y), n represents an integer of ¹ ~ 10, R 1 ^'represents a divalent aromatic hydrocarbon group of a carbon number of 2-20 divalent aliphatic or alicyclic hydrocarbon group, or a carbon number of 5-20 in. Two R ² in each repeating unit ^"is a one-way is -NH-, the other ^{is> NC (= O) -R 3} ' is a group represented by. R ^{3 'is} a hydroxyl group or a carbon-represents a group having a carbon unsaturated bond.

Formula R ^{3 'wherein} at least one R ^3' of the (Y) is a carbon-carbon unsaturated bond is a group having the.

Among the reactive additives represented by the formula (Y), a compound represented by the following formula (YY) (hereinafter sometimes referred to as compound (YY)) is particularly preferred (and n has the same meaning as described above).

[Formula 15]

Commercially available products can be used for the compound (YY) or purified as necessary. As a commercial item, Laromer (trademark) LR-9000 (made by BASF Corporation) is mentioned, for example.

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, and preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the liquid crystal compound.

(Coating method of composition for polarizing layer formation)

Examples of the method for coating the composition for forming the polarizing layer include extrusion coating, direct gravure coating, reverse gravure coating, CAP coating, slit coating, micro gravure, die coating, and inkjet. Moreover, the method of coating using a coater, such as a dip coater, a bar coater, and a spin coater, etc. are mentioned. Among them, in the case of continuously coating in a roll-to-roll form, the coating method by microgravure method, inkjet method, slit coating method, die coating method is preferred, and uniformity when coating on sheet-fed substrates such as glass This high spin coating method is preferred. In the case of coating in a roll-to-roll form, an alignment layer forming composition or the like is coated on the base layer 13 to form an alignment layer 12, and a composition for forming a polarizing layer is continuously coated on the obtained alignment layer 12. You may.

When forming the polarizing layer 11 by coating the composition for forming a polarizing layer, a solvent is removed from the coated composition for forming a polarizing layer to form a coating layer for a polarizing layer. As a method of removing the solvent, the same method as the method of removing the solvent from the oriented polymer composition can be used, and examples thereof include natural drying, air drying, heat drying, reduced pressure drying, and a combination of them. Among them, 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 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, an active energy ray is irradiated on the coating layer for a polarizing layer formed in the polarizing layer forming step, and photopolymerization of the polymerizable liquid crystal compound is performed to photopolymerize the polarizing layer (11 It is preferred to form. As the active energy ray to be irradiated, the type of the polymerizable liquid crystal compound (especially, the type of the photopolymerizable functional group of the polymerizable liquid crystal compound) contained in the coating layer for the polarizing layer, and when the photopolymerization initiator is included, the photopolymerization initiator It is appropriately selected according to the type and their amount. Specifically, at least one light selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays, and γ-rays can be cited. Among them, ultraviolet light is preferred because it is easy to control the progress of the polymerization reaction and that a photopolymerization device that is widely used in the art can be used, and it is polymerizable so that it can be photopolymerized by ultraviolet light. It is preferable to select the type of liquid crystal compound.

As the light source of the active energy ray, for example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, a xenon lamp, a halogen lamp, a carbon arc lamp, a tungsten lamp, a gallium lamp, an excimer laser, a wavelength range of 380- And an LED light source emitting 440 nm, a chemical lamp, a black light lamp, a microwave-excited mercury lamp, and a metal halide lamp.

The irradiation intensity of the active energy ray is usually 10 Pa/cm 2 to 3000 Pa/cm 2. The irradiation intensity of the active energy ray is preferably an intensity in a wavelength region effective for activation of a cationic polymerization initiator or a radical polymerization initiator. The time for irradiating 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, and even more preferably 0.1 seconds to 1 minute. When irradiated once or plural times with the irradiation intensity of the active energy ray, the accumulated light amount is 10 mJ/cm 2 to 3000 mJ/cm 2, preferably 50 mJ/cm 2 to 2,000 mJ/cm 2, more preferably 100 mJ /Cm2-1000 mJ/cm2. When the accumulated light amount is less than this range, curing of the polymerizable liquid crystal compound is insufficient, and good transferability may not be obtained. Conversely, when the integrated light amount is more than this range, the polarizing layer may be colored.

(Protection layer lamination process)

In the protective layer lamination step, as shown in Fig. 2(c), on the polarizing layer 11 of the laminated film 62 prepared in the preparation step, a covering region 35a for coating the polarizing layer 11, and A protective layer 35 having an exposed region 35b for exposing the polarizing layer 11 is laminated. Thereby, the protective layer forming laminated film 63 can be obtained. The exposed region 35b can be, for example, an opening of the protective layer 35. The coating region 35a suppresses the dissolution liquid from contacting the polarization layer 11 when the dissolving liquid capable of dissolving the polarizing layer 11 described later and the protective layer-forming laminated film 63 are brought into contact with each other. Can. On the other hand, in the exposed region 35b of the protective layer 35, the dissolved solution can be brought into contact with the polarizing layer 11.

As will be described later, when the polarizing layer 11 contacts the dissolving solution, the dissolving solution dissolves the polarizing layer 11. Therefore, it is preferable to form the exposed region 35b in correspondence with the region in which the polarizing layer 11 is dissolved. For example, when manufacturing the polarizing film 1 shown in FIG. 1 and FIG. 2(e), it is preferable to determine the shape according to the shape of the low polarization area 11b. For example, when viewed from the plane of the low polarization region 11b, the shape is circular; Oval; Jang, Won-Hyung; Polygons such as triangles, squares, squares, and rhombuses; Line shape; Band shape; If it is corrugated, etc., the exposed areas 35b may be formed corresponding to these shapes. Circular; Oval; Jang, Won-Hyung; When polygons such as triangles, squares, squares, and lozenges are regularly formed on a long polarizing film of 10 m or more, the present production method, which can be prepared without interposing a photomask, is excellent in productivity compared to prior art documents 1 and 2.

For example, when the exposed area 35b is circular, the diameter is preferably 5 cm or less, more preferably 3 cm or less, and even more preferably 2 cm or less. When the exposed area 35b is elliptical or elliptical, its long axis is preferably 5 cm or less, more preferably 3 cm or less, and even more preferably 2 cm or less. When the exposed area 35b is a polygon, the diameter of the virtual circle drawn so that this polygon is inscribed is preferably 5 cm or less, more preferably 3 cm or less, and even more preferably 2 cm or less. As will be described later, since the solution penetrates into the polarizing layer, the size of the exposed region 35b may be formed to be slightly smaller than the size of the low polarized region 11b.

Moreover, it is preferable to form the covering region 35a of the protective layer 35 in correspondence with the region in which the polarizing layer 11 is not dissolved. For example, when manufacturing the polarizing film 1 shown in FIG. 1 and FIG. 2(e), it is preferable to determine the shape according to the shape of the polarization region 11a.

As the protective layer 35, one in which a region serving as the exposed region 35b is formed on a sheet-like substrate can be used. The area to be the exposed area 35b is a method of mechanically punching a predetermined portion of the sheet-like substrate by punching, cutting plotter, water jet, or the like, and removing a predetermined portion of the sheet-like substrate by laser ablation, chemical dissolution, or the like. It can be formed by a method or the like.

As a sheet-like base material forming the protective layer 35, when the polarizing layer 11 to be described later is brought into contact with a dissolving solution capable of dissolving, it is insoluble in the dissolving solution, and in order to remove the dissolving solution or the dissolved polarizing layer The material is not particularly limited as long as it has durability under the washing conditions to be performed. As the sheet-like base material forming the protective layer 35, for example, it can be formed using the same material as the above-described base material layer 13, particularly preferably formed using a resin base material, and the protective layer It is more preferable to use a polyester resin such as polyethylene terephthalate which is easy to suppress deformation of the region (for example, an opening) that becomes the exposed region 35b of (35).

It is preferable that the protective layer 35 has an adhesive layer for bonding to the polarizing layer 11. Since the protective layer is peeled off as described later, it is preferable that the adhesive layer can be peeled off from the polarizing layer 11. Moreover, the thickness of the protective layer 35 is usually 20 µm or more, preferably 30 µm or more, and further preferably 250 µm or less and 200 µm or less.

(Solution contact process)

In the solution contacting step, the patterned polarizing layer 11 formed by removing a portion of the polarizing layer 11 by bringing the protective layer-forming laminated film 63 into contact with the dissolving solution capable of dissolving the polarizing layer 11 A patterned polarizing layer forming film 64 having') can be obtained (Fig. 2(d)). Since the protective layer 35 of the protective layer-forming laminated film 63 has a covering region 35a for covering the polarizing layer 11 and an exposed region 35b for exposing the polarizing layer 11, In the exposed region 35b, the dissolving solution and the polarizing layer 11 may contact. Thereby, the polarizing layer 11 in the contact part with a dissolving liquid is removed, and the region which does not contain a liquid crystal compound and a dichroic dye can be formed.

The contact between the protective layer-forming laminated film 63 and the dissolving solution is performed by applying, spraying, dropping, or the like, the dissolving solution onto the protective layer-forming laminated film 63 in which the protective layer-forming laminated film 63 is immersed in the solution. It can be carried out, and it is preferable to carry out by a method of immersing the protective layer-forming laminated film 63 in a solution. Thereby, in the polarizing layer 11, the dissolving liquid contacts the surface of the polarizing layer 11 exposed from the exposed region 35b of the protective layer 35, and the liquid crystal compound and the dichroic dye are also removed. As a result, a patterned polarization layer forming film 64 having a patterned polarization layer 11' having a partial region of the polarization layer 11 removed and a polarization region 11a and a low polarization region 11b formed (FIG. 2(d)).

On the surface of the polarizing layer 11, the region coated on the covering region 35a of the protective layer 35 does not readily dissolve the polarizing layer 11 because the polarizing layer 11 does not directly contact the dissolving solution. Does not. On the other hand, in the region exposed from the exposed region 35b of the protective layer 35 in the polarizing layer 11, the polarizing layer 11 is easily soluble because the polarizing layer 11 directly contacts the dissolving solution. , The liquid crystal compound and the dichroic dye are easy to be removed. Therefore, in the patterned polarizing layer forming film 64 shown in Fig. 2(d), the polarizing layer 11 remains in the region corresponding to the covering region 35a in the polarizing layer 11, and the exposed region 35b In the region corresponding to ), a patterned polarizing layer 11' having a low polarization region 11b from which a liquid crystal compound and a dichroic dye is removed can be formed.

In this way, the protective layer-forming laminated film 63 in which the exposed region 35b of the protective layer 35 is disposed in the region to remove the liquid crystal compound and the dichroic dye constituting the polarizing layer 11 in the polarizing layer 11 ), the patterned polarizing layer 11' in which the liquid crystal compound and the dichroic dye are removed at the desired position of the polarizing layer 11 can be formed. Since the solution melts the polarizing layer 11, the thickness of the protective layer 35, the size of the exposed area 35b, the concentration of the solution, so that the polarizing layer 11 in the unnecessary area is not removed , It is preferable to adjust the immersion time of the protective layer-forming laminated film with respect to the dissolved solution, the coating amount of the dissolved solution to the protective layer-forming laminated film 63, the amount of spraying, or the amount of dripping.

The dissolving solution is not particularly limited as long as the polarizing layer 11 is dissolved and the base layer 13 and the protective layer 35 are not dissolved, but an organic solvent is preferable. For example, aromatic hydrocarbons such as anisole and toluene, ethers such as tetrahydrofuran and dimethoxyethane, ethyl acetate, butyl acetate, esters such as ethylene glycol methyl ether acetate, γ-butyrolactone, acetone, methyl ethyl ketone, And chlorine-containing solutions such as ketones such as cyclopentanone and chloroform. These solvents may be used alone or in combination.

The contact conditions for bringing the protective layer-forming laminated film 63 into contact with the dissolving solution may be appropriately selected depending on the thickness of the polarizing layer 11, the size of the region from which the polarizing layer 11 is removed, and the like. The temperature of the solution is preferably 10 to 80°C, more preferably 20 to 60°C.

In the solution contacting step, it is preferable to provide a washing step in which the protective layer-forming laminated film 63 is brought into contact with the solution to remove a portion of the polarizing layer 11 and then the solution or the dissolved polarizing layer is washed. The washing step can be carried out by appropriately using one that does not dissolve the polarizing layer 11, such as water or alcohol.

(Peeling process)

In the peeling step, the protective layer 35 is peeled from the patterned polarizing layer forming film 64 obtained in the liquid material contacting step. Thereby, the polarizing film 1 (FIG. 1 and FIG. 2(e)) containing the patterned polarizing layer 11' which has the polarization region 11a and the low polarization region 11b can be obtained.

The polarizing film 1 shown in FIGS. 1 and 2(e) can also be used by peeling off the base layer 13. In this case, the alignment layer 12 may be peeled together with the base layer 13. For example, peeling of the base material layer 13 can also be carried out after bonding the patterned polarizing layer 11' of the polarizing film 1 to a member constituting a display device, a retardation layer, or the like.

(Method for continuously producing a polarizing film)

The manufacturing method of the polarizing film 1 can be preferably produced continuously by Roll to Roll type. In this case, in the preparation step, a laminated film wound in a roll shape may be prepared, conveyed while unwinding the laminated film, and a protective layer lamination step, a solution contacting step, and a peeling step may be continuously performed. In the protective layer lamination process, the protective layer wound in a roll shape may be conveyed while unwinding, and a protective layer-forming laminated film may be obtained by laminating a protective layer on the laminated film. In the solution contacting step, the solution layer-filled laminated film is continuously conveyed while passing the solution bath filled with the solution, or the solution is coated, sprayed or dropped while continuously transporting the protective layer-forming laminated film, It is sufficient to obtain a patterned polarizing layer forming film. In the peeling step, the protective layer may be continuously peeled while conveying the patterned polarizing layer forming film, and the polarizing film may be wound into a roll to form a wound body. The polarizing film continuously produced as described above may have a length of 10 m or more, for example.

Moreover, when a preparatory process has an orientation layer formation process, you may just convey, unwinding the base layer wound in roll shape, and apply|coating the composition for formation of an alignment layer continuously with this application layer with an application device to form an orientation layer. . When the preparation step has a polarizing layer forming step, while continuously conveying the alignment layer forming base layer, a polarizing layer is formed by coating a composition for forming a polarizing layer on the side of the alignment layer forming base layer on which the alignment layer is formed. You can do it.

[Second embodiment (original polarizing plate and method for manufacturing the same)]

(Circular polarizer)

3(a) to 3(c) are schematic cross-sectional views each showing an example of the original polarizing plate of the present invention. The polarizing film 1 shown in FIG. 2(e) is laminated to the retardation layer 15 having a 1/4 wavelength plate function, thereby forming the original polarizing plates 5a, 5b shown in FIGS. 3(a) and (b). can do. The retardation layer 15 may be laminated on the patterned polarizing layer 11' side of the polarizing film 1 (FIG. 3(a)) or may be laminated on the base layer 13 side (FIG. 3(b)). ). Moreover, what peeled the base material layer 13 from the circular polarizing plate 5a shown in FIG. 3(a) can also be used as a circular polarizing plate 5c (FIG. 3(c)), In this case, the base layer 13 In addition, the alignment layer 12 may be peeled off.

Moreover, the original polarizing plate may be a laminate of the polarizing film 1 and the retardation layer having a multilayer structure. In this case, as a retardation layer having a multilayer structure, a retardation layer in which a layer having a 1/2 wavelength plate function and a layer having a 1/4 wavelength plate function can be used, and a 1/2 wavelength plate of the multilayer structure retardation layer can be used. By laminating the layer side which has a function and the polarizing film 1, it can be set as a circular polarizing plate. Alternatively, as a retardation layer having a multi-layer structure, a circular polarizing plate can also be obtained by using a retardation layer in which a layer having a 1/4 wavelength plate function having reverse wavelength dispersion and a layer having a positive C plate function is laminated.

Moreover, you may use what has a function as a phase difference layer as the base material layer 13 of the polarizing film 1, and may also make a circular polarizing plate by laminating a phase difference layer further. In this case, the function as the retardation layer which the base layer 13 and the retardation layer has may be selected depending on the lamination positions of the base layer 13 and the retardation layer in the original polarizing plate.

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

(Manufacturing method of circular polarizer)

The original polarizing plate can be produced by laminating a polarizing film and a retardation layer. When the polarizing film is a long polarizing film having a length of 10 m or more continuously manufactured, by using a long retardation layer having a length of 10 m or more as the retardation layer, and stacking the long polarizing film and the long retardation layer while continuously conveying both, It is preferable to form a long laminate. At this time, it is preferable to laminate both by applying an adhesive or an adhesive to at least one of the long polarizing film and the long retardation layer.

The manufacturing method of the original polarizing plate may have a process of cutting a long-length laminated body obtained by laminating a long polarizing film and a long retardation layer into a sheet of a predetermined size in order to mount the polarizing film to a display device of a predetermined size or the like. In the cutting step, it is preferable to cut the long stacked body in at least one of the longitudinal direction and the width direction of the long stacked body. In this case, it is preferable to determine the cutting position in the long stacked body so that the low polarization region is disposed at a predetermined position in the cut sheet.

Example

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

"%" and "part" in an Example and a comparative example are mass% and mass part unless otherwise specified.

[Visibility Correction Polarization (Py) and Visibility 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 of Examples, Comparative Examples and Reference Examples were prepared. Moreover, what cut|disconnected the same film used as a base material layer in each Example, a comparative example, and a reference example to 40 mm x 40 mm was prepared as a base material layer of an evaluation sample. Using these, except for not using a protective layer, the same procedure as in the preparation of the polarizing films of each Example, Comparative Example, and Reference Example was carried out to obtain samples for evaluation.

(Visibility corrected polarization (Py) and visibility corrected transmittance (Ty))

With respect to the evaluation sample, the luminous sensitivity corrected single transmittance (Ty) and the luminous corrected polarization degree (Py) were calculated in the following procedure. A device in which the transmittance (T ₁ ) in the transmission axis direction and the transmittance (T ₂ ) in the absorption axis direction are set in a wavelength range of 380 nm to 780 nm, and a polarizer forming folder is set in a spectrophotometer (UV-3150 manufactured by Shimadzu Corporation) It was measured by the double beam method. The folder was provided with a mesh for cutting the amount of light by 50% on the reference side. The transmittance and polarization degree at each wavelength were calculated using the following (Equation 1) and (Equation 2), and the visibility was corrected by a 2-degree field of view (C light source) of JIS Z 8701, and the visibility was corrected. Ty) and visibility corrected polarization degree (Py) were calculated.

Polarization degree [%] = {(T ₁ ― T ₂ ) / (T ₁ + T ₂ )} × 100 (Equation 1)

Simple substance transmittance [%] = (T ₁ + T ₂ )/2 (Equation 2)

[Example 1]

(Preparation 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.

Two polymers having photoreactive groups shown below

[Formula 16]

Solvent: 98 parts of o-xylene

(Preparation of composition for polarizing layer formation)

The composition for polarizing layer formation was obtained by mixing the following components and stirring at 80 degreeC for 1 hour. As the dichroic dye, the azo-based dye described in the examples of JP 2013-101328 A was used.

75 parts of polymerizable liquid crystal compound represented by formula (1-6)

[Formula 17]

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

[Formula 18]

・The dichroic dye shown below (1) 2.8 parts

[Formula 19]

2.8 parts of dichroic colors shown below (2)

[Formula 20]

・The dichroic dye shown below (3) 2.8 parts

[Formula 21]

-Polymerization initiator 6 parts shown below

2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (Irgacure 369; manufactured by Chiba Specialty Chemicals)

・Leveling agent shown below 1.2 parts

Polyacrylate compound (BYK-361N; manufactured by BYK-Chemie)

・250 parts of solvent shown below

Cyclopentanone

(Preparation of polarizing film)

A triacetyl cellulose film (KC4UY-TAC manufactured by Konica Minolta, 40 µm thick) as a base layer was cut to 20×20 mm, and corona-treated (AGF-B10, manufactured by Kasuga Electric Co., Ltd.) was applied to the surface. After applying the composition for forming an alignment layer to the surface of the film subjected to the corona treatment using a bar coater, it was dried for 1 minute in a drying oven set at 120°C to obtain a coating layer for the alignment layer. Using the polarized UV irradiation device (SPOT CURE SP-7; manufactured by Ushio Electric Co., Ltd.) on the coating layer for the alignment layer, the accumulated light amount of 50 mJ/cm 2 (based on 313 nm) of polarized UV in the 0° direction with respect to the film side Irradiated with to form an alignment layer. On the obtained alignment layer, a composition for forming a polarizing layer was applied using a bar coater, and then dried for 1 minute in a drying oven set at 110°C. Then, using a high-pressure mercury lamp (Unicure VB-15201BY-A, manufactured by Ushio Electric Co., Ltd.), irradiating ultraviolet rays (in a nitrogen atmosphere, the wavelength: 365 nm, the total light intensity at a wavelength of 365 nm: 1000 mJ/cm 2) , A polarizing layer in which a liquid crystal compound and a dichroic dye were aligned was obtained. On the polarizing layer, a protective layer formed by opening a hole by drilling a hole with a punch punch (AY-638 manufactured by Fujimori Industries Co., Ltd. is composed of an adhesive layer having a thickness of 15 µm on a polyester film having a thickness of 38 µm) After sticking together, it was immersed in anisole as a solution for 10 seconds. Then, the protective layer was peeled off to obtain a polarizing film.

As a result of visually observing the appearance of the obtained polarizing film, it was found that a circular region (low polarization region) in which no polarizing layer was present was clearly confirmed, and a polarizing film having a polarization region and a low polarization region was obtained. Moreover, the sample for evaluation was produced in the above-mentioned order, and the visibility correction transmittance (Ty) and the visibility correction polarization (Py) were computed. Table 1 shows the results.

[Example 2]

As a base layer, instead of a triacetylcellulose film, a hard coat treatment was performed on the surface of a quarter-wave plate (Zeonoa Film, Nippon Xeon Corporation, in-plane retardation value Ro: 138 nm), which is a uniaxially stretched film of a cyclic olefin resin. Using the film, a polarizing film was obtained in the same manner as in Example 1, except that the slow axis and the absorption axis of the polarizing layer were laminated so as to be 45°. As a result of visually observing the appearance of the obtained polarizing film, it was found that a circular region (low polarization region) in which no polarizing layer was present was clearly confirmed, and a polarizing film having a polarization region and a low polarization region was obtained. Moreover, the sample for evaluation was produced in the above-mentioned order, and the visibility correction transmittance (Ty) and the visibility correction polarization (Py) were computed. Table 1 shows the results.

[Example 3]

A polarizing film was obtained in the same manner as in Example 1 except that tetrahydrofuran was used as the solution. As a result of visually observing the appearance of the obtained polarizing film, it was found that a circular region (low polarization region) in which no polarizing layer was present was clearly confirmed, and a polarizing film having a polarization region and a low polarization region was obtained. Moreover, the sample for evaluation was produced in the above-mentioned order, and the visibility correction transmittance (Ty) and the visibility correction polarization (Py) were computed. Table 1 shows the results.

[Comparative example]

A polarizing film was obtained in the same manner as in Example 1 except that methanol was used as the solution. As a result of visually observing the appearance of the obtained polarizing film, it was found that a region in which no polarizing layer was present could not be confirmed, and 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 order, and the visibility correction transmittance (Ty) and the visibility correction polarization (Py) were computed. Table 1 shows the results.

[Reference example]

A polarizing film was obtained in the same manner as in Example 1 except that no dissolved solution was used. As a result of visually observing the appearance of the obtained polarizing film, it was found that a region in which no polarizing layer was present could not be confirmed, and 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 order, and the visibility correction transmittance (Ty) and the visibility correction polarization (Py) were computed. Table 1 shows the results.

In addition, the values of the visibility correction transmittance (Ty) and the visibility correction polarization degree (Py) measured in each of the Examples, Comparative Examples and Reference Examples shown in Table 1 are the visibility correction transmittance (Ty) and the visibility correction polarization of the base layer. Although it is a value including the value of (Py), since the visibility correction transmittance (Ty) of the base layer alone is 92%, and the value of the visibility correction polarization (Py) of the substrate layer is 0%, each example shown in Table 1 , In Comparative Examples and Reference Examples, when the substrate layer was excluded, the value of the visibility corrected transmittance (Ty) was greater than the value shown in Table 1, and the value of the visibility corrected polarization (Py) became the same as the value shown in Table 1. I think.

1: Polarizing film
5a to 5c: circular polarizer
11: polarizing layer
11': Patterned polarizing layer
11a: Polarization area
11b: Low polarization area
12: alignment layer
13: base layer
15: retardation layer
35: protective layer
35a: covering area
35b: exposed area
61: base layer forming alignment layer
62: laminated film
63: laminated film forming a protective layer
64: patterned polarizing layer forming film

Claims (14)

A preparation step of preparing a laminated film having a polarizing layer containing a dichroic dye on at least one side of the base layer;
A protective layer laminating process for obtaining a protective layer-forming laminated film by laminating a protective layer having a coating region for coating the polarizing layer and an exposed region for exposing the polarizing layer on the polarizing layer of the laminated film,
The solution contacting step of obtaining a patterned polarizing layer forming film having a patterned polarizing layer formed by removing a portion of the polarizing layer by bringing the protective layer forming laminated film into contact with a dissolving solution capable of dissolving the polarizing layer. and,
The manufacturing method of a polarizing film which has a peeling process which peels the said protective layer from the said patterned polarizing layer forming film. According to claim 1,
The preparation process,
An alignment layer forming process of forming an alignment layer by coating a composition for forming an alignment layer on one side of the base layer;
A method of manufacturing a polarizing film having a polarizing layer forming step of forming a polarizing layer by coating a composition for forming a polarizing layer comprising a liquid crystal compound and the dichroic dye on a side of the substrate layer on which the alignment layer is formed. . According to claim 2,
The composition for forming an alignment layer includes a photo-alignment polymer,
In the alignment layer forming step, a polarization irradiation is performed on a coating layer for an alignment layer formed by coating the composition for forming an alignment layer to form the alignment layer, wherein the alignment layer is produced. The method of claim 2 or 3,
The polarizing layer is a layer in which a polymerizable liquid crystal compound is aligned,
In the polarizing layer forming step, the polarizing layer is formed by coating the composition for forming the polarizing layer to form the polarizing layer by performing active energy ray irradiation on the coating layer for the polarizing layer. The method according to any one of claims 2 to 4,
The said polarizing layer shows the Bragg peak in X-ray diffraction measurement, The manufacturing method of a polarizing film. The method according to any one of claims 1 to 5,
The exposed area has a circular, elliptical, elliptical, or polygonal shape when viewed in a plane,
When the exposed area is circular, the diameter is 5 cm or less,
The long diameter when the exposed area is oval or elliptical is 5 cm or less,
When the exposed area is a polygon, the diameter of the virtual circle drawn so that the polygon is inscribed is 5 cm or less, a method of manufacturing a polarizing film. The method according to any one of claims 1 to 6,
The length of the polarizing film is 10 m or more, a method of manufacturing a polarizing film. The method according to any one of claims 1 to 7,
The said base material layer has a 1/4 wavelength plate function, The manufacturing method of a polarizing film. The manufacturing method of the original polarizing plate which has the polarizing film manufactured by the manufacturing method of the polarizing film of any one of Claims 1-7, and the retardation layer lamination process which laminates the retardation layer which has a 1/4 wavelength plate function. . The method of claim 9,
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 lamination process, the elongated polarizing film and the elongated retardation layer are laminated to form a long elongated laminate,
Further, the manufacturing method of the circular polarizing plate which has a cutting process of cutting the said long laminated body into single sheets. A polarizing film having a polarization region and a low polarization region having a lower visibility correction polarization than the polarization region,
The polarization region contains a liquid crystal compound and a dichroic dye, and the visibility correction polarization degree is 90% or more,
The low polarization region does not contain a liquid crystal compound and a dichroic dye,
The low polarization region has a circular, elliptical, elliptical, or polygonal shape when viewed in a plane,
When the low polarization region is circular, the diameter is 5 cm or less,
The long diameter when the low polarization region is oval or elliptical is 5 cm or less,
When the low polarization region is a polygon, the diameter of the virtual circle drawn so that the polygon is inscribed is 5 cm or less, a polarizing film. The method of claim 11,
The said low polarization area is a polarizing film whose visibility correction polarization degree is 10% or less. The method of claim 11 or 12,
In the polarization region, the visibility correction simple substance transmittance is 35% or more,
The said low polarization area|region is a polarizing film in which the visibility correction simple substance transmittance|permeability is 80% or more. The method according to any one of claims 11 to 13,
The length of the polarizing film is 10 m or more, a polarizing film.

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