JP2017182017A - Polarizing plate, method for producing polarizing film, and method for producing polarizing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polarizing plate having reduced cracks in its peripheral part; a method for producing a polarizing film capable of suitably producing the polarizing plate; and a method for producing a polarizing plate capable of suitably producing the polarizing plate.SOLUTION: A polarizing plate has: a polarizer layer that contains a polyvinyl alcohol resin as a formation material and in which a dichroic dye is adsorbed and oriented; a resin layer provided on at least a part of a peripheral part of a first surface, in the first surface of the polarizer layer; an adhesive layer which overlaps planarly with the resin layer and is provided so as to cover the whole surface of the first surface; and a protective layer which overlaps planarly with the adhesive layer and is provided so as to cover the whole surface of the first surface, where the polarizer layer has a crosslinked region in which the polyvinyl alcohol resin is crosslinked with a crosslinking agent and a non-crosslinked region in which crosslinking with the crosslinking agent proceeded less efficiently than the crosslinked region, and the non-crosslinked region is provided so as to overlap planarly with the resin layer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a polarizing plate, a method for producing a polarizing film, and a method for producing a polarizing plate.

  A polarizing plate is used as a polarization supply element in a display device such as a liquid crystal display device. Conventionally, a polarizing film (polarizer layer) made of polyvinyl alcohol resin (PVA resin) is used as such a polarizing plate.

  Conventional liquid crystal display devices, such as TV monitors and mobile phones, are based on the assumption that the display area is rectangular. For this reason, most of the conventional polarizing plates have a rectangular shape corresponding to the display area.

  However, in recent years, the shapes of liquid crystal display devices have been diversified, and the shapes of display areas have also been diversified. For example, in a device adopting a liquid crystal display device for an instrument panel (instrument panel, instrument panel) of an automobile or a display unit of a wristwatch, a liquid crystal display device whose shape of the display area does not become a rectangle is required in order to improve design. ing. Therefore, as polarizing plates used in such a liquid crystal display device, polarizing plates having various shapes other than a rectangular shape are required depending on the shape of the display region.

  Here, in this specification, “solid polarizing plates having various shapes other than rectangular and square shapes in plan view” are collectively referred to as “atypical polarizing plates” or “atypical polarizing plates”. Sometimes. “Solid” means that a polarizer layer is present on the entire surface of the inner region from the outermost periphery in plan view. In this sense, even if the planar view shape of a certain polarizing plate is rectangular or square, a polarizing plate having a through-hole in the innermost region from the outermost periphery in a planar view is a deformed polarizing plate.

  For example, Patent Document 1 describes a method for manufacturing a deformed polarizing plate having a through hole.

International Publication No. 2007/108244

  The polarizing plate is manufactured by dyeing a long PVA resin film and cross-linking with a cross-linking agent, and then machining and cutting the unit into a unit size. However, when the irregularly shaped polarizing plate is cut into a unit size, cracks are likely to occur at the cut portion, and there is a problem in the appearance of the product. Furthermore, in a harsh environment where high and low temperatures are repeated, the polarizer layer may be cracked starting from the generated crack, and improvement has been demanded.

  This invention is made | formed in view of such a situation, Comprising: It aims at providing the polarizing plate with which the crack of the peripheral part was reduced. Another object is to provide a method for producing a polarizing film capable of suitably producing the polarizing plate as described above. Another object of the present invention is to provide a method for producing a polarizing plate capable of suitably producing the polarizing plate as described above.

  In order to solve the above-described problem, an embodiment of the present invention includes a polarizer layer in which a polyvinyl alcohol resin is a forming material and a dichroic dye is adsorbed and oriented, and the first surface of the polarizer layer includes: A resin layer provided on at least a part of a peripheral edge of one surface, an adhesive layer provided to cover the entire surface of the first surface, overlapping the resin layer, and the adhesive layer; And a protective layer provided so as to cover the entire surface of the first surface, and the polarizer layer includes a crosslinked region in which the polyvinyl alcohol-based resin is crosslinked with a crosslinking agent, and the crosslinked layer. And a non-crosslinked region in which crosslinking by the crosslinking agent has not progressed more than the region, and the non-crosslinked region provides a polarizing plate provided to overlap the resin layer in a planar manner.

  In one embodiment of the present invention, the resin layer may have a configuration using a photocurable resin as a forming material.

  In one aspect of the present invention, the thickness of the polarizer layer in the crosslinked region is equal to the thickness of the polarizer layer in the non-crosslinked region, and the thickness of the resin layer is the thickness of the polarizer layer. It is good also as a structure below 2 times.

  In one aspect of the present invention, the polarizer layer may have a thickness of 10 μm or less.

  Another embodiment of the present invention is a method in which a polyvinyl alcohol-based resin solution is applied to the surface of a belt-shaped base film to obtain a laminated film, and the base film and the base film are formed on the surface. Stretching together the polyvinyl alcohol-based resin layer to obtain a laminated stretched film; and forming a resin layer on at least a part of the surface of the polyvinyl alcohol-based resin layer in the laminated stretched film; A method for producing a polarizing film, comprising: a step of dyeing a laminated stretched film on which the resin layer is formed with a dichroic dye, and crosslinking the polyvinyl alcohol resin with a crosslinking agent to form a polarizer layer. provide.

  One embodiment of the present invention includes a step of drawing a polyvinyl alcohol-based resin film to obtain a stretched film, a step of forming a resin layer on the stretched film, and a laminated stretched film on which the resin layer is formed. And a step of forming a polarizer layer by cross-linking the polyvinyl alcohol resin with a cross-linking agent. In the step of forming the resin layer, one of the first surfaces of the stretched film is provided. A method for producing a polarizing film is provided in which a first resin layer is formed on the portion, and a second resin layer is formed on the second surface of the stretched film at a position that overlaps at least the first resin layer.

  One embodiment of the present invention includes a step of obtaining a laminate in which a stretched film in which a polyvinyl alcohol-based resin film is stretched is laminated on the surface of a band-shaped base film, and the layer of the stretched film in the laminate A step of forming a resin layer on at least a part of the surface of the layer; a laminate on which the resin layer is formed is dyed with a dichroic dye; and the stretched film is crosslinked with a crosslinking agent to form a polarizer layer The manufacturing method of a polarizing film provided with the process of forming is provided.

  In one embodiment of the present invention, the resin layer may be formed by applying a solution obtained by dissolving the resin layer forming material in an organic solvent and then volatilizing the organic solvent.

  In one embodiment of the present invention, the resin layer may be formed by irradiating with light after forming a coating film of a photocurable resin that is a material for forming the resin layer.

  Another embodiment of the present invention provides a method for producing a polarizing plate, comprising: a step of producing a polarizing film by the method for producing a polarizing film; and a step of cutting the polarizing film along the resin layer. .

  ADVANTAGE OF THE INVENTION According to this invention, the polarizing plate with which the crack of the peripheral part was reduced can be provided. Moreover, the manufacturing method of the polarizing film which can manufacture suitably the above polarizing plates can be provided. Moreover, the manufacturing method of the polarizing plate which can manufacture the above polarizing plates suitably can be provided.

The schematic perspective view which shows the polarizing plate of 1st Embodiment. FIG. 2 is a cross-sectional view taken along arrow II-II in FIG. 1. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing plate of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing plate of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing plate of 1st Embodiment. Explanatory drawing of the manufacturing method of the polarizing film of 1st Embodiment. Sectional drawing which shows the manufacturing method of the polarizing film of 2nd Embodiment. Sectional drawing which shows the manufacturing method of the polarizing film of 2nd Embodiment. Sectional drawing which shows the manufacturing method of the polarizing film of 2nd Embodiment. Sectional drawing which shows the manufacturing method of the polarizing plate of 2nd Embodiment. The top view which shows the example of the unusual shaped polarizing plate which can be suitably manufactured with the polarizing plate of this invention, and the manufacturing method of a polarizing plate. Explanatory drawing of an Example.

[First Embodiment]
Hereinafter, the polarizing plate, the manufacturing method of the polarizing film, and the manufacturing method of the polarizing plate according to the first embodiment of the present invention will be described with reference to FIGS. In all the drawings below, the dimensions and ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

<Polarizing plate>
FIG. 1 is a schematic perspective view showing a polarizing plate of the present embodiment.

  As shown in the figure, the polarizing plate 1 of the present embodiment is not a rectangle and a square in plan view, but a pair of sides facing each other in the rectangle are arcs that bulge outward. In the figure, the arc-shaped side in plan view is denoted by reference numeral 1a, and the remaining pair of opposite sides is denoted by reference numeral 1b. The polarizing plate 1 of the present embodiment is an “irregular” polarizing plate according to the definition described above.

2 is a cross-sectional view taken along the line II-II in FIG.
As illustrated in FIGS. 1 and 2, the polarizing plate 1 of the present embodiment includes a polarizer layer 11, a resin layer 12, an adhesive layer 13, and a protective layer that are sequentially stacked on the first surface 11 a of the polarizer layer 11. 14, and an adhesive layer 15, a protective layer 16, an adhesive layer 17, and a release film 18 that are sequentially stacked on the second surface 11 b of the polarizer layer 11.

(Polarizer layer)
The polarizer layer 11 is obtained by dyeing a film having a polyvinyl alcohol resin (hereinafter sometimes abbreviated as PVA resin) with a dichroic dye and adsorbing and orienting the dichroic dye. . The PVA resin film constituting the polarizer layer 11 is stretched, and the dichroic dye is oriented in the stretching direction to form an absorption axis. In the figure, the absorption axis is indicated by a double-headed arrow with the symbol A. In the present embodiment, the absorption axis A is set to be parallel to the side 1b of the polarizing plate 1 and intersect the arcuate side 1a.

  The draw ratio of the PVA resin film is preferably more than 5 times, more preferably more than 5 times and not more than 17 times.

  When manufacturing a thin polarizing laminated film, the thickness of the polarizer layer 11 is 10 micrometers or less, Preferably it is 7 micrometers or less. In order to further suppress cracks during cutting and to suppress cracking of the polarizer layer in a harsh environment where high and low temperatures are repeated, it is preferable to use a thick polarizer layer. In this case, the thickness of the polarizer layer 11 is 10 μm or more and 50 μm or less, preferably 12 μm or more and 30 μm or less, more preferably 12 μm or more and 25 μm or less. In a thin liquid crystal display device preferred in the recent market, the polarizer layer 11 is preferably 10 μm or less.

  As the PVA resin, a saponified polyvinyl acetate resin can be used. Examples of the polyvinyl acetate resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers with other monomers copolymerizable with vinyl acetate. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.

  The PVA resin used for the polarizer layer 11 preferably has a saponification degree of 80 mol% or more, more preferably 90 mol% or more, and further preferably 94 mol% or more. If the degree of saponification is too low, the water resistance and heat-and-moisture resistance after making the polarizing plate may not be sufficient. Also, it may be a completely saponified product (having a saponification degree of 100 mol%), but if the saponification degree is too high, the dyeing speed becomes slow, and the production time is required to give sufficient polarization performance. In some cases, the polarizer may become long or a polarizer having sufficient polarization performance may not be obtained. Therefore, the saponification degree of the PVA resin used for the polarizer layer 11 is preferably 99.5 mol% or less, and more preferably 99.0 mol% or less. The upper limit value and the lower limit value of the saponification degree can be arbitrarily combined.

The degree of saponification as used herein refers to the unit ratio (mol%) of the proportion of acetate groups (acetoxy groups: —OCOCH ₃ ) contained in the polyvinyl acetate resin that is the raw material of the PVA resin changed to hydroxyl groups by saponification treatment. And is defined by the following formula:
Saponification degree (mol%) = [(number of hydroxyl groups) ÷ (number of hydroxyl groups + number of acetate groups)] × 100.

  The higher the degree of saponification, the higher the proportion of hydroxyl groups, and hence the lower the proportion of acetate groups that inhibit crystallization. The degree of saponification can be determined by the method specified in JIS K6726-1994 “Testing method for polyvinyl alcohol”.

  The PVA resin used in this embodiment may be a modified polyvinyl alcohol that is partially modified. For example, PVA resin modified with olefins such as ethylene and propylene, modified with unsaturated carboxylic acids such as acrylic acid, methacrylic acid and crotonic acid, modified with alkyl ester of unsaturated carboxylic acid, acrylamide And the like modified with. The proportion of modification is preferably less than 30 mol%, and more preferably less than 10 mol%. When modification exceeding 30 mol% is performed, it becomes difficult to adsorb the dichroic dye, resulting in a problem that the polarization performance is lowered.

  The average degree of polymerization of the PVA resin is usually in the range of about 100 to 10000, preferably 1500 to 8000, and more preferably 2000 to 5000. The average degree of polymerization here can also be determined by the method defined in JIS K6726-1994 “Testing method for polyvinyl alcohol”.

  As PVA resin having such characteristics, “PVA124” (saponification degree: 98.0-99.0 mol%) and “PVA117” (saponification degree: 98.0-99.0) sold by Kuraray Co., Ltd. Mol%), “PVA624” (degree of saponification 95.0-96.0 mol%) and “PVA617” (degree of saponification 94.5-95.5 mol%); sold by Nippon Synthetic Chemical Industry Co., Ltd. "AH-26" (degree of saponification 97.0-98.8 mol%), "AH-22" (degree of saponification 97.5-98.5 mol%), "NH-18" (degree of saponification) 98.0-99.0 mol%) and "N-300" (degree of saponification 98.0-99.0 mol%); "JC-33" (ken Degree of conversion of 99.0 mol% or more), "JM-33" (degree of saponification 93.5- 5.5 mol%), "JM-26" (degree of saponification 95.5-97.5 mol%), "JP-45" (degree of saponification 86.5-89.5 mol%), "JF- 17 "(degree of saponification 98.0-99.0 mol%)," JF-17L "(degree of saponification 98.0-99.0 mol%) and" JF-20 "(degree of saponification 98.0) 99.0 mol%) (all are trade names), and these can be suitably used in the present invention.

  Specific examples of the dichroic dye used for dyeing the PVA resin layer include iodine and dichroic organic dyes. Examples of dichroic organic dyes include red BR, red LR, red R, pink LB, Rubin BL, Bordeaux GS, sky blue LG, lemon yellow, blue BR, blue 2R, navy RY, green LG, violet LB, Violet B, Black H, Black B, Black GSP, Yellow 3G, Yellow R, Orange LR, Orange 3R, Scarlet GL, Scarlet KGL, Congo Red, Brilliant Violet BK, Spura Blue G, Spura Blue GL, Spura Orange GL, Direct There are Sky Blue, Direct First Orange S and First Black. These dyes are commercially available. Only one type of dichroic dye may be used, or two or more types may be used in combination.

  The polarizer layer 11 included in the polarizing plate 1 of the present embodiment includes a crosslinked region 11α in which the PVA resin is crosslinked with a crosslinking agent, and a non-crosslinked region 11β in which the crosslinking by the crosslinking agent is not proceeding more than the crosslinked region 11α. Have.

  The bridging region 11α is provided in a region inside the outer periphery of the polarizing plate 1 in plan view. Further, the non-crosslinked region 11β is provided so as to surround the periphery of the crosslinked region 11α along the outer periphery of the polarizing plate 1 in plan view.

  In the crosslinking region 11α, a boron compound, glyoxal, or glutaraldehyde can be used as a crosslinking agent for crosslinking the PVA resin. Of these, boron compounds are preferred. Examples of the boron compound include boric acid and borax. Only 1 type may be used for a crosslinking agent and it may use 2 or more types together.

  Such a cross-linked region 11α is dyed with the dichroic dye while the PVA resin is cross-linked with the cross-linking agent. On the other hand, in the non-crosslinked region 11β, the crosslinking with the crosslinking agent is not progressed more than the crosslinked region 11α, and the dichroic dye is hardly dyed.

  Therefore, the cross-linked region 11α and the non-cross-linked region 11β are greatly different in appearance and have different hardness due to the progress of the cross-linking. Specifically, the cross-linked region 11α is cured as the cross-linking progresses and has a higher hardness than the non-cross-linked region 11β. On the other hand, the non-crosslinked region 11β maintains the flexibility of the PVA resin as a raw material because the crosslinking has not progressed. Such a difference in hardness between the crosslinked region 11α and the non-crosslinked region 11β can be detected, for example, by measuring the piercing strength by the method described in Examples described later. Moreover, the difference in the amount of the crosslinking region 11α, the non-crosslinked region 11β, and the crosslinking agent can be detected by a known analysis method.

  For the puncture strength measurement, a polarizer test piece is used. The test piece may be of a size that allows the polarizer to be fixed. The puncture strength is measured when this specimen is fixed to a jig, pierced from the normal direction, pierced by the jig, and split in one direction in the direction parallel to the stretching direction (absorption axis direction). What is necessary is just to measure the intensity | strength of. The measurement is performed on five or more test pieces, and the average value can be obtained as the puncture strength. By dividing the measured piercing strength by the thickness of the polarizer used for the measurement, the piercing strength per unit film thickness can be calculated.

  The puncture strength of the region where the resin layer is not provided in the polarizer layer 11 is preferably 3 g / μm or more, more preferably 5 g / μm or more, and usually 10 g / μm or less. Further, the puncture strength of the region where the resin layer is provided is preferably 11 g / μm or more, and more preferably, measurement is impossible without breaking.

  The cross-linked region 11α and the non-cross-linked region 11β may have different thicknesses, but are preferably the same thickness from the standpoint of manufacturing ease. In FIG. 2, the cross-linked region 11α and the non-cross-linked region 11β are shown as having the same thickness. When the cross-linked region 11α and the non-cross-linked region 11β have the same thickness, the polarizer layer 11 can be easily manufactured by using a PVA resin film having a uniform thickness. In addition, “the same thickness” means that there is substantially no thickness difference without actively providing a thickness difference, and a configuration that does not strictly include a thickness difference due to a manufacturing error or the like. It does not point. For example, the thickness difference can be 1 μm or less.

(Resin layer)
On the first surface 11a of the polarizer layer 11, the resin layer 12 is provided on at least a part of the peripheral edge of the first surface 11a. The resin layer 12 is continuously provided in an annular shape so as to overlap the above-described non-crosslinked region 11β in a plane.

  As the material for forming the resin layer 12, various materials can be used as long as they do not deteriorate or deteriorate in the manufacturing process described later. For example, as a material for forming the resin layer 12, for example, cyclic polyolefin resin, cellulose acetate resin such as triacetyl cellulose and diacetyl cellulose, polyethylene terephthalate, polyethylene naphthalate, polyester resin such as polybutylene terephthalate, polycarbonate resin, Acrylic resins and polypropylene resins can be employed.

  Moreover, as a forming material of the resin layer 12, it is preferable that they are thermoplastic resins, such as (meth) acrylic-type resin, and a photocurable resin. The thermoplastic resin such as (meth) acrylic resin is preferably easily diluted with an organic solvent. The photocurable resin is more preferably an ultraviolet curable resin.

  The resin layer 12 may be transparent or colored. When the resin layer 12 is colored, the resin layer 12 preferably contains a dye and a pigment. By coloring the resin layer 12, the appearance of the polarizing plate can be improved. The color can be selected from red, blue, green, etc. according to market needs. In terms of improving the appearance, it is preferable to color the resin layer 12 in black and to adjust the single transmittance to the same level as the region without the resin layer. The transmittance (single transmittance) when only the resin layer 12 is measured is preferably 38% to 50%, more preferably about 40% to 43%. The material for forming the resin layer 12, the degree of coloring, and the film thickness of the resin layer 12 are adjusted so that the single transmittance of the resin layer 12 has such values. When an ultraviolet curable resin is used for the resin layer, the single transmittance may be 50% or more in that the curing can be easily performed.

  As a photocurable resin, what hardened | cured the composition of the reactive monomer and the photoinitiator can be used. Examples of the reactive monomer include those that react by cationic polymerization, anionic polymerization, or radical polymerization of an epoxy-containing monomer, a vinyl ether monomer, a (meth) acrylic monomer, and the like. These monomers may be used alone or in combination of two or more. As the photopolymerization initiator, known cationic polymerization initiators, anionic polymerization initiators, and radical polymerization initiators can be appropriately used. Of course, each of the polymerization initiators may be used alone or in combination.

  It is preferable to use a photocurable resin as a forming material of the resin layer 12 because the resin layer 12 having various shapes can be easily manufactured and the degree of design freedom is increased.

  The thickness of the resin layer 12 is preferably 2 times or less of the thickness of the polarizer layer 11, and preferably 1 time or less of the thickness of the polarizer layer 11. The resin layer 12 can be manufactured by a method for manufacturing a polarizing film, which will be described later, and may be thin as long as the target function can be exhibited.

  For example, when the thickness of the polarizer layer 11 is 10 μm, the thickness of the resin layer 12 may be 20 μm (twice the thickness of the polarizer layer 11), or 10 μm (the thickness of the polarizer layer 11). 1 μm), 5 μm (0.5 times the thickness of the polarizer layer 11), or 2 μm (0.2 times the thickness of the polarizer layer 11). Good.

  The width of the resin layer 12 is, for example, 20 mm or less. Here, the width of the resin layer 12 refers to the shortest distance from the outer periphery of the polarizing plate 1 to the inner periphery of the resin layer 12 when the polarizing plate 1 is viewed in plan. The width of the resin layer 12 is preferably 10 mm or less, and more preferably 5 mm or less. When the width of the resin layer 12 is reduced, the liquid crystal display device using the polarizing plate 1 can be narrowed.

(Adhesive layer)
The adhesive layer 13 overlaps the resin layer 12 in a plan view and is provided so as to cover the entire surface of the first surface 11a. Examples of the adhesive that forms the adhesive layer 13 include water-based polyvinyl alcohol resins, urethane adhesives, polyester adhesives, vinyl acetate emulsion adhesives, and acrylic adhesives. Of these, polyvinyl alcohol resins are preferably used. A polyhydric aldehyde, a water-soluble epoxy compound, a melamine compound, a zirconia compound, a zinc compound, or the like may be added to the adhesive as an additive. If it is a photocurable resin, what reacts by photocations, anion polymerization, or radical photopolymerization, such as an epoxy resin type and a (meth) acrylic type, can be mentioned, for example. Among these, a photocationic polymerization type epoxy resin is preferable.
The adhesive layer 13 and the resin layer 12 may be formed from the same composition, or may be formed from different compositions.

(Protective layer)
The protective layer 14 overlaps with the adhesive layer 13 in a plan view and is provided to cover the entire surface of the first surface 11a. The protective layer 14 is bonded to the polarizer layer 11 via the adhesive layer 13.

  The protective layer 14 may not have an optical function, or may have an optical function such as a retardation film or a brightness enhancement film.

  The material constituting the protective layer 14 is not particularly limited. For example, a cyclic polyolefin resin, a cellulose acetate resin such as triacetyl cellulose or diacetyl cellulose, a polyester resin such as polyethylene terephthalate, polyethylene naphthalate, or polybutylene terephthalate, polycarbonate Materials that have been widely used in the field such as resin, acrylic resin, and polypropylene resin can be used.

  The cyclic polyolefin resin is a commercially available product such as “TOPAS” manufactured by TOPAS ADVANCED POLYMERS and sold in Japan by Polyplastics Co., Ltd., “Arton” sold by JSR Co., Ltd., and ZEON Corporation “Zeonor” and “ZEONEX” sold by the company, “Apel” sold by Mitsui Chemicals, Inc. (both are trade names) can be suitably used. In order to form such a cyclic polyolefin-based resin into a film, a known method such as a solvent casting method or a melt extrusion method is appropriately used. In addition, “Essina retardation film” sold by Sekisui Chemical Co., Ltd., “ZEONOR FILM” sold by Nippon Zeon Co., Ltd. You may use the commercial item of the cyclic polyolefin resin film to which the phase difference was provided.

  The cyclic polyolefin resin film may be uniaxially stretched or biaxially stretched. An arbitrary retardation value can be imparted to the cyclic polyolefin-based resin film by stretching. Stretching is normally performed continuously while unwinding the film roll, and is stretched in the heating furnace in the roll traveling direction, in the direction orthogonal to the traveling direction, or both. The temperature of the heating furnace is usually in the range from the vicinity of the glass transition temperature of the cyclic polyolefin resin to the glass transition temperature + 100 ° C. The draw ratio is usually 1.1 to 6 times, preferably 1.1 to 3.5 times in one direction.

  Since the cyclic polyolefin resin film is generally inferior in surface activity, the surface on the side of the polarizer layer 11 is subjected to surface treatment such as plasma treatment, corona treatment, ultraviolet irradiation treatment, flame (flame) treatment, and saponification treatment. Is preferred. Among these, plasma treatment and corona treatment that can be performed relatively easily are preferable.

  Examples of the cellulose acetate-based resin film include commercially available products such as “Fujitac TD80”, “Fujitac TD80UF”, “Fujitac TD80UZ” and “Fujitac TD40UZ” sold by FUJIFILM Corporation, Konica Minolta Advanced Layer Co., Ltd. “KC8UX2M”, “KC4UY”, “KC2UA”, etc. (all of which are trade names) can be suitably used.

  A liquid crystal layer or the like may be formed on the surface of the cellulose acetate-based resin film in order to improve viewing angle characteristics. Moreover, in order to provide a phase difference, the stretched cellulose acetate type-resin film can also be used. The cellulose acetate-based resin film is usually subjected to a saponification treatment in order to improve the adhesion with the polarizer layer. The saponification treatment is performed by immersing the film in an aqueous solution of an alkali such as sodium hydroxide or potassium hydroxide.

  An optical layer such as a hard coat layer, an antiglare layer, or an antireflection layer can be formed on the surface of the protective layer 14 as described above. The method for forming these optical layers on the surface of the protective film is not particularly limited, and a known method can be used.

  The thickness of the protective layer 14 is preferably as thin as possible from the viewpoint of thinning, and more preferably 90 μm or less and 50 μm or less. On the other hand, if the thickness is too thin, the strength may decrease and the processability may be hindered.

(Adhesive layer)
The adhesive layer 15 is provided so as to cover the front edge of the second surface 11 b of the polarizer layer 11. Examples of the material for forming the adhesive layer 15 include the same materials as those for the adhesive layer 13 described above.

(Protective layer)
The protective layer 16 overlaps with the adhesive layer 15 and is provided so as to cover the entire surface of the second surface 11b. The protective layer 16 is bonded to the polarizer layer 11 via the adhesive layer 15. Examples of the material for forming the protective layer 16 include the same materials as the protective layer 14 described above. In order to reduce the thickness of the polarizing plate, the formation of the protective layer 16 may be omitted.

(Adhesive layer)
The adhesive layer 17 overlaps with the protective layer 16 and is provided so as to cover the entire surface of the second surface 11b. The pressure-sensitive adhesive layer 17 may be provided on the resin layer 12 side. As a forming material of the adhesive layer 17, for example, an acrylic resin, a styrene resin, a silicone resin or the like is used as a base polymer, and a composition in which a crosslinking agent such as an isocyanate compound, an epoxy compound, or an aziridine compound is added to the forming material. The pressure-sensitive adhesive (pressure-sensitive adhesive) is used. Additives such as a silane coupling agent, an antioxidant, an ultraviolet absorber, and an ultraviolet stabilizer may be appropriately added to the composition.

  In this specification, an “adhesive” is a liquid when it is applied to a base material and wets the base material and solidifies to develop adhesiveness (that is, until it solidifies, it exhibits adhesiveness). Not).

  Further, in this specification, the “pressure-sensitive adhesive” is a flexible rubber-like material, and immediately exhibits adhesiveness by attaching itself. When using an adhesive, a solidification process is not required.

(Peeling film)
The release film 18 overlaps with the adhesive layer 17 and is provided so as to cover the entire surface of the second surface 11b. The release film 18 is detachably attached to the protective layer 16 via the adhesive layer 17.

  Examples of the release film 18 include extruded films of thermoplastic resins such as polyethylene terephthalate, polyethylene naphtholate, polyethylene, and polypropylene, co-extruded films combining them, and films obtained by stretching them uniaxially or biaxially. be able to. As the transparent resin film, it is preferable to use polyethylene terephthalate or polyethylene uniaxially or biaxially stretched film which is excellent in transparency and homogeneity and is inexpensive.

  The thickness of the release film 18 is preferably 15 μm or more and 75 μm or less. When the thickness is 15 μm or more, handling becomes easy and the originally required surface protection performance can be secured. On the other hand, when the thickness is 75 μm or less, the rigidity does not become too strong, the handling becomes easy, and the peel strength is appropriately suppressed.

[Production method of polarizing film]
Next, the manufacturing method of the polarizing film of this embodiment and the manufacturing method of a polarizing plate are demonstrated. 3 to 15 are explanatory views of the polarizing film manufacturing method and the polarizing plate manufacturing method of the present embodiment.

  First, as shown in FIG. 3, a polyvinyl alcohol-based resin solution is applied to the surface of the belt-like base film 21 </ b> A to obtain a laminated film 31.

  As shown in FIG. 3, the base film 21 </ b> A unwound from the unwinding roll 101 is conveyed in the longitudinal direction by the conveying roll 102. A coating device 109 for applying a polyvinyl alcohol resin solution is provided in the transport path, and a coating film 19 of the polyvinyl alcohol resin solution is formed on the surface of the base film 21A. By drying the coating film, a laminated film (laminated body) 31 of the PVA layer 11A having a polyvinyl alcohol resin as a forming material and the base film 21A is obtained.

  As a polyvinyl alcohol-type resin, what was mentioned above can be used. Moreover, as a solvent of a polyvinyl alcohol-type resin solution, although water and polar organic solvents, such as alcohol, ketones, and esters, can be used, it is preferable to use water. A polar organic solvent may be appropriately added to the aqueous solution of the polyvinyl alcohol resin.

  When the PVA layer 11A is formed by the above method, a plasticizer can be added to the polyvinyl alcohol resin solution used. Examples of the plasticizer include polyhydric alcohols such as ethylene glycol, glycerin, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, and trimethylolpropane. Only one type of plasticizer may be used, or two or more types may be used in combination. In particular, ethylene glycol and glycerin are preferably used. Moreover, antiblocking agents, such as surfactant, can also be used together as needed.

  As a coating method of the polyvinyl alcohol-based resin solution, a roll coating method such as a wire bar coating method, a reverse coating method and a gravure coating method, a die coating method, a comma coater method, a lip coating method, a screen coating method, a spray method and the like are known. A method can be appropriately selected and employed.

  As the resin used for the base film 21A, for example, a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, stretchability and the like is used. The base film 21A is stretched together with the base film 21A in the polarizer forming step described later. Therefore, it is preferable to use the base film 21A that can be similarly stretched in a temperature range suitable for stretching the PVA layer 11A. In that case, an appropriate film may be selected based on the glass transition temperature Tg or the melting point Tm of the thermoplastic resin forming the base film 21A.

  In this embodiment, it is preferable to use the base film 21 that is not stretched in the stretching direction of the laminated film 30 in the stretching process. Moreover, although the base film 21 may be extended | stretched regarding the direction orthogonal to the extending | stretching process in a extending | stretching process, and the laminated | multilayer film 30 surface, it is preferable that it is unstretched.

  Specific examples of the thermoplastic resin that is a material for forming the base film 21A include polyolefin resins, polyester resins, cyclic polyolefin resins (norbornene resins), (meth) acrylic resins, cellulose ester resins, and polycarbonate resins. Resins, polyvinyl alcohol resins, vinyl acetate resins, polyarylate resins, polystyrene resins, polyethersulfone resins, polysulfone resins, polyamide resins, polyimide resins, and mixtures and copolymers thereof. It is done.

  The base film 21A may be a film formed using only one kind of the above-described resin, or may be a film formed using a mixture of two or more kinds of resins. Moreover, the base film 21 may be a single layer film or a multilayer film.

  Examples of the polyolefin resin include polyethylene and polypropylene. Polyethylene, polypropylene, and the like are preferable because they can be stably stretched at a high magnification. Moreover, an ethylene-polypropylene copolymer obtained by copolymerizing propylene with ethylene can also be used. Copolymerization can be performed with other types of monomers, and examples of other types of monomers copolymerizable with propylene include ethylene and α-olefins.

  The stereoregularity of the propylene resin constituting the propylene resin film is preferably substantially isotactic or syndiotactic. A propylene-based resin film made of a propylene-based resin having substantially isotactic or syndiotactic stereoregularity has relatively good handleability and excellent mechanical strength in a high-temperature environment.

  Arbitrary appropriate additives may be added to the base film 21 </ b> A in addition to the thermoplastic resin. Examples of such additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, mold release agents, anti-coloring agents, flame retardants, nucleating agents, antistatic agents, pigments, and coloring agents. .

  The content of the thermoplastic resin exemplified above in the base film 21A is preferably 50% by mass to 100% by mass, more preferably 50% by mass to 99% by mass, and further preferably 60% by mass to 98% by mass. Especially preferably, it is 70 mass%-97 mass%. This is because when the content of the thermoplastic resin in the base film 21A is less than 50% by mass, the high transparency and the like inherent in the thermoplastic resin may not be sufficiently exhibited.

  The thickness of the base film 21A before stretching can be determined as appropriate, but in general, from the viewpoint of workability such as strength and handleability, 1 μm to 500 μm is preferable, 1 μm to 300 μm is more preferable, and 5 μm to 200 μm is preferable. More preferably, 5 μm to 150 μm is even more preferable.

  In order to improve the adhesion with the PVA layer 11A, the base film 21A may be subjected to corona treatment, plasma treatment, flame treatment, or the like on at least the surface on which the PVA layer 11A is formed. Further, in order to improve the adhesion, a primer layer using a material that exhibits a certain degree of strong adhesion to both the base film 21A and the PVA layer 11A on the surface of the base film 21A facing the PVA layer 11A May be formed.

  The material for forming the primer layer is not particularly limited as long as the material exhibits a certain degree of strong adhesion to both the base film 21A and the PVA layer 11A. For example, a thermoplastic resin excellent in transparency, thermal stability, stretchability, etc. is used. Specific examples include acrylic resins and polyvinyl alcohol resins, but are not limited thereto.

  Next, as shown in FIGS. 4 and 5, the laminated film 31 is stretched, that is, the base film 21 </ b> A and the PVA layer 11 </ b> A formed on the surface of the base film 21 </ b> A are stretched together to obtain the laminated stretched film 32.

  FIG. 4 shows a state in which the laminated film 31 is drawn by a fixed end drawing method to obtain a laminated drawn film 32. “Fixed end stretching” refers to stretching while suppressing shrinkage of the film in a direction perpendicular to the stretching direction when the film is stretched in one direction. As a method of stretching at the fixed end, for example, in roll stretching performed using a transport roll while heating in a heating furnace, a method of shortening the distance between the rolls and stretching in the transport direction, hot roll stretching, stretching by a tenter method. Can be mentioned.

  As shown in FIG. 4, the laminated film 31 unwound from the unwinding roll 121 is introduced into a heating furnace (not shown). In the heating furnace, the laminated film 31 is sequentially conveyed in the longitudinal direction of the laminated film 31 while being held by the plurality of holding portions 129 at both ends in the width direction of the laminated film 31. The holding part 129 stretches the laminated film 31 in the width direction (TD direction indicated by reference sign D1 in the drawing) by applying a stress spreading in the width direction to the laminated film 31 to form a laminated stretched film 32.

  Here, about the longitudinal direction (MD direction shown by code | symbol D2 in the figure) of the laminated stretched film 32, the rotational speed of the unwinding roll 121 and rolls, such as a conveyance roll and a winding roll arrange | positioned downstream. It is good also as extending | stretching by the difference of, and it is good also as not extending | stretching.

  Further, the unwinding speed of the unwinding roll 121 is made faster than that of a roll such as a transport roll or a winding roll arranged on the downstream side, and the longitudinal direction of the laminated film 31 is contracted and stretched in the width direction of the laminated film 31. You may let them. In this specification, such a stretching method of stretching in the width direction while contracting in the transport direction may be referred to as “simultaneous biaxial stretching”.

  FIG. 5 shows how the laminated film 31 is drawn by free end uniaxial drawing to obtain a laminated drawn film 32. “Free end stretching” refers to stretching without stretching the film in a direction perpendicular to the stretching direction when stretching the film in one direction. Examples of the free end stretching method include a method of stretching an unstretched resin film due to a difference in rotational speed between two or more rolls, and a method called a long span stretching method. The long span stretching method uses a longitudinal stretching machine having two pairs of nip rolls and an oven arranged therebetween, and stretches the unstretched resin film in the oven by a difference in rotational speed between the two pairs of nip rolls. It is.

  As shown in FIG. 5, the laminated film 31 is transported in the longitudinal direction by transport rollers 122 to 126. The laminated film 31 is introduced into a heating furnace (not shown) in the transport path. Here, the conveyance rolls 123-126 shall be arrange | positioned in the heating furnace. In the heating furnace, the laminated film 31 is wound around a transport roll 124 that rotates at a low speed and a transport roll 125 that rotates at a high speed, and is transported in the longitudinal direction.

  While the laminated film 31 is heated in the heating furnace, the longitudinal direction (MD direction indicated by reference sign D3 in the figure) is determined between the transport roll 124 and the transport roll 125 due to a difference in peripheral speed between the transport roll 124 and the transport roll 125. ) In the short direction (TD direction indicated by reference sign D4 in the figure) to become a laminated stretched film 32B.

  In the laminated stretched film 32 obtained by stretching by the above method, the thickness of the stretched film obtained by stretching the PVA layer 11A is, for example, preferably 10 μm or less, and more preferably 1 μm or more.

  The draw ratio in the drawing step is preferably more than 5 times, more preferably more than 6 times, more preferably 7 times or more, and usually 10 times or less, although it depends on the drawing method employed. .

  Next, as shown in FIGS. 6 and 7, the resin layer 12 </ b> A is formed on at least a part of the surface of the PVA layer 11 </ b> B in the laminated stretched film 32. FIG. 6 is a process diagram showing a process of forming the resin layer 12A, and FIG. 7 is a cross-sectional view taken along arrow VII-VII in FIG.

  The resin layer 12A is a belt-like layer provided on the surface of the PVA layer 11B. The resin layer 12A includes a pair of linear portions 12x facing each other and an arc portion 12y that connects ends of the pair of linear portions 12x. The linear portion 12 x is provided in parallel with the longitudinal direction of the laminated stretched film 32, and the arc portion 12 y is provided so as to intersect with the longitudinal direction of the laminated stretched film 32. Thereby, the surface of the PVA layer 11B is divided into areas AR1 and AR3 that are exposed without being protected by the resin layer 12A, and an area AR2 that is protected by the resin layer 12A. The region AR1 is a region surrounded by the resin layer 12A, and the region AR3 is a region outside the resin layer 12A.

  The resin layer 12A may be formed by transferring a separately formed film-like resin layer 12A onto the surface of the PVA layer 11B, or may be formed by printing on the surface of the PVA layer 11B. As the forming material of the resin layer 12A, the same material as the forming material of the resin layer 12 described above can be used.

  When the resin layer 12A is formed by printing, the printing method of the resin layer 12A includes an inkjet method, a gravure coating method, a roller coating method, a dip coating method, a spray coating method, a spinner coating method, a curtain coating method, a slot coating method, A screen printing method or the like can be employed.

  Among these, the inkjet method, the gravure coating method, and the screen printing method are preferable because the resin layer 12 can be selectively formed on a part of the surface of the PVA layer 11B. When using such a printing method, it is preferable to use an epoxy resin or a (meth) acrylic resin as a material for forming the resin layer 12.

  That is, according to these printing methods, a solution in which a resin that is a material for forming the resin layer 12 is dissolved in an organic solvent is printed on the surface of the PVA layer 11B to form a coating film. The resin layer 12 can be formed by volatilizing.

  In addition, when a method with a low printing resolution is adopted among the above printing methods, a position corresponding to the area AR1 is masked in advance before the resin layer 12A is formed, and then a forming material for the resin layer 12A is applied. The resin layer 12A may be formed. In this case, it is preferable to use a photocurable resin as a forming material of the resin layer 12A. After printing the photocurable resin, the resin layer 12A can be formed by appropriately irradiating light to cure the forming material and further removing the mask.

  That is, according to these printing methods, the resin layer 12 can be formed by irradiating light after forming a coating film of a photocurable resin that is a material for forming the resin layer 12.

  FIG. 6 shows a state in which the resin layer 12A is formed by adopting the ink jet method and discharging the forming material of the resin layer 12A from the nozzle N.

  Next, as illustrated in FIGS. 8 to 11, the laminated stretched film 32 on which the resin layer 12 </ b> A is formed is dyed with a dichroic dye, and the PVA resin is crosslinked with a crosslinking agent to form a polarizer layer.

  FIG. 8 is a process diagram showing a process of dyeing with a dichroic dye, and FIG. 9 is a cross-sectional view of the laminated stretched film 33 after dyeing. The cross-sectional view of FIG. 9 is the position corresponding to FIG.

  As shown in FIG. 8, the laminated stretched film 32 is transported in the longitudinal direction by transport rolls 131 to 134. The laminated stretched film 32 is immersed in a dyeing solution 141 in which a dichroic dye is dissolved in a dyeing bath 140 provided in the conveying path, and is conveyed while being dyed.

  At this time, in the PVA layer 11B of the laminated stretched film 32, the areas AR1 and AR3 that are not protected by the resin layer 12A are dyed. On the other hand, the area AR2 protected by the resin layer 12A is less dyed than the areas AR1 and AR3. In FIG. 9, the dyed area 11x is a dyed area that is the PVA layer of the areas AR1 and AR3, and the undyed area 11y is a dyed area that is the PVA layer of the area AR2.

  In the present embodiment, the PVA layer 11B constituting the laminated stretched film 32 is dyed with a dichroic dye. Examples of the dichroic dye include iodine and the organic dyes described above.

  The dyeing process is performed, for example, by immersing the entire laminated stretched film 32 in a solution (dye solution) in which a dichroic dye is dissolved in a solvent. As a solvent for the dyeing solution, water is generally used, but an organic solvent compatible with water may be further added.

  The concentration of the dichroic dye is preferably 0.01% by mass to 10% by mass, more preferably 0.02% by mass to 7% by mass, and 0.025% by mass to 5% by mass. It is particularly preferred.

  When iodine is used as the dichroic dye, it is preferable to further add an iodide because the dyeing efficiency can be further improved. Examples of the iodide include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, and iodide. Examples include titanium. The addition ratio of these iodides is preferably 0.01% by mass to 20% by mass in the dyeing solution.

  Of the iodides, it is preferable to add potassium iodide. When adding potassium iodide, the ratio of iodine to potassium iodide is preferably in the range of 1: 5 to 1: 100, more preferably in the range of 1: 6 to 1:80, by mass ratio. , Particularly preferably in the range of 1: 7 to 1:70.

  The immersion time of the laminated stretched film 32 in the dyeing solution is not particularly limited, but is preferably in the range of 15 seconds to 15 minutes, and more preferably 1 minute to 3 minutes. Moreover, it is preferable that the temperature of a dyeing | staining solution exists in the range of 10 to 60 degreeC, and it is more preferable that it exists in the range of 20 to 40 degreeC.

  In this way, the laminated stretched film 33 having the dyed PVA layer 11C is obtained.

FIG. 10 is a process diagram illustrating a process of crosslinking the PVA resin with a crosslinking agent, and FIG. 11 is a cross-sectional view of the laminated stretched film 34 after crosslinking. The cross-sectional view of FIG. 11 is a position corresponding to FIG.
As shown in FIG. 10, the laminated stretched film 33 is transported in the longitudinal direction by transport rolls 151 to 154. The laminated stretched film 33 is immersed in a crosslinking solution 161 in which a crosslinking agent is dissolved in a crosslinking bath 160 provided in the conveyance path, and conveyed while being crosslinked.

  At this time, in the PVA layer 11C of the laminated stretched film 33, the areas AR1 and AR3 that are not protected by the resin layer 12A are cross-linked. On the other hand, the area AR2 protected by the resin layer 12A is less likely to be cross-linked than the areas AR1 and AR3. FIG. 11 shows a PVA layer in the regions AR1 and AR3 and a cross-linked layer as a cross-linked region 11α, and a PVA layer in the region AR2 and a non-stained layer as a non-cross-linked region 11β.

  The crosslinking treatment is performed by immersing the entire laminated stretched film 33 in a solution containing a crosslinking agent (crosslinking solution). Conventionally known substances can be used as the crosslinking agent. Examples thereof include boron compounds such as boric acid and borax, glyoxal, and glutaraldehyde. One type of cross-linking agent may be used, or two or more types may be used in combination.

  As the crosslinking solution, a solution in which a crosslinking agent is dissolved in a solvent can be used. As the solvent, for example, water can be used, but an organic solvent compatible with water may be further included. Although the density | concentration of the crosslinking agent in a crosslinking solution is not limited to this, It is preferable to exist in the range of 1 mass%-20 mass%, and it is more preferable that it is 6 mass%-15 mass%.

  Iodide may be added to the crosslinking solution. By adding iodide, the in-plane polarization characteristics of the resin layer can be made more uniform. Examples of the iodide include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, and titanium iodide. Is mentioned. The content of iodide is 0.05% by mass to 15% by mass, more preferably 0.5% by mass to 8% by mass.

  The immersion time of the laminated film in the crosslinking solution is preferably 15 seconds to 20 minutes, and more preferably 30 seconds to 15 minutes. Moreover, it is preferable that the temperature of a crosslinking solution exists in the range of 10 to 80 degreeC.

In this way, a laminated stretched film 34 having a crosslinked PVA layer, that is, a polarizing film 11D is obtained. The obtained polarizing film 11 </ b> D has an absorption axis in the longitudinal direction of the laminated stretched film 34. The polarizing film 11D corresponds to the polarizing film in the present invention.
The manufacturing method of the polarizing film of this embodiment is as described above.

  Next, as shown in FIG. 12, while the laminated stretched film 34 is being transported by the transport roll 171, the coating device 172 provided in the transport path is planarly overlapped with the resin layer 12 </ b> A and the entire surface of the first surface 11 a. An adhesive is applied so as to cover. Thereby, the adhesive layer 13A is formed. As the material for forming the adhesive layer 13A, the same material as the material for forming the adhesive layer 13 described above can be used.

  Further, a protective film 14A as a protective layer forming material is unwound from an unwinding roll 173 provided downstream of the coating device 172, and overlaps with the adhesive layer 13A and the pair of rolls 174, 175. The laminated stretched film 34 and the protective film 14A are laminated through the adhesive layer 13A and bonded by passing between a pair of rolls 174 and 175. Thereby, the laminated stretched film 35 is formed. As the material for forming the protective film 14A, the same material as that for forming the protective layer 14 described above can be used.

  In FIG. 12, after the adhesive is applied to the laminated stretched film 34 by the coating device 172, the protective film 14 </ b> A is pasted. However, the present invention is not limited thereto, and the adhesive is applied to the protective film 14 </ b> A. After that, the laminated stretched film 34 may be bonded.

  After peeling the base film 21B from the laminated stretched film 35, the laminated stretched film 35 shown as a cross-sectional view in FIG. 13 is obtained by forming a laminated structure on the exposed polarizing film 11D by a known method. The cross-sectional view of FIG. 13 is the position corresponding to FIG. In addition, you may use as a protective film as it is, without peeling the base film 21B.

  As shown in the figure, the laminated stretched film 35 has a protective layer 16A bonded to the second surface 11b of the polarizing film 11D via an adhesive layer 15A, and is removable to the protective layer 16A via an adhesive layer 17A. And an attached release film 18A.

As the material for forming the adhesive layer 15A, the same material as the material for forming the adhesive layer 15 described above can be used.
As the material for forming the protective layer 16A, the same material as that for forming the protective layer 16 described above can be employed.
As the material for forming the adhesive layer 17A, the same material as that for forming the adhesive layer 17 described above can be used.
As the material for forming the release film 18A, the same material as that for forming the release film 18 described above can be used.

  Next, as shown in FIGS. 14 and 15, in the laminated stretched film 35, the polarizing film 11 </ b> D is cut along the resin layer 12 </ b> A to form the polarizing plate 1. 14 and 15, the cutting position is indicated by a dashed-dotted virtual line VR.

  The laminated stretched film 35 is cut using a cutting blade C. In this step, the laminated stretched film 35 may be cut by moving the cutting blade C along the resin layer 12A. Further, by using a frame-shaped punching blade that is larger than the inner diameter of the resin layer 12A and smaller than the outer diameter as the cutting blade C, the laminated stretched film 35 is cut at a time by descending vertically from above the laminated stretched film 35. Also good.

Here, the non-cross-linked region 11β that overlaps the resin layer 12A in a plan view is softer than the cross-linked region 11α because the cross-linking has not progressed, and the flexibility of the PVA resin that is the raw material is maintained. Therefore, it is possible to easily manufacture a polarizing plate in which cracks are hardly generated in the polarizing film 11D due to the stress at the time of cutting with the cutting blade C, and cracks at the peripheral edge (cutting position) are reduced.
The manufacturing method of the polarizing plate of this embodiment is as described above.

According to the polarizing plate having the above-described configuration, it is possible to provide a polarizing plate in which cracks at the peripheral portion are reduced.
Moreover, according to the manufacturing method of the above polarizing films, the manufacturing method of the polarizing film which can manufacture the above polarizing plates suitably can be provided.
Moreover, according to the manufacturing method of the above polarizing plates, the above polarizing plates can be manufactured suitably.

  In the present embodiment, the resin layer 12 is described as being continuous in an annular shape, but is not limited thereto.

  It has been empirically found that cracks are less likely to occur when the strip-shaped polarizing film is cut in the absorption axis direction and the transmission axis direction even when the entire surface of the polarizing film is cross-linked when manufacturing an irregularly shaped polarizing plate. That is, a portion where cracks are likely to occur at the time of cutting is a portion where the polarizing film is cut in a direction intersecting at an angle other than orthogonal to the absorption axis direction of the polarizing film, that is, polarized in a direction other than the absorption axis direction and the transmission axis direction of the polarizing film. This is where the film is cut. In the present embodiment, cracks are unlikely to occur when the position of the side 1b shown in FIG. 1 is cut, and cracks are likely to occur when the position shown in the side 1a is cut. The absorption axis direction of the polarizing film coincides with the longitudinal direction (MD direction) when the PVA layer is stretched in the longitudinal direction during production. Further, the transmission axis direction of the polarizing film coincides with the width direction (MD direction) when the PVA layer is stretched in the longitudinal direction at the time of production.

  Therefore, the resin layer 12 may be formed only at a position where cracks are likely to occur during cutting, and the resin layer 12 may not be formed at positions where it is empirically known that cracks are unlikely to occur.

  In the present embodiment, the PVA layer is formed only on one surface of the base film. However, the present invention is not limited to this, and the PVA layer is formed on both surfaces of the base film. A polarizer layer may be formed.

[Second Embodiment]
In the first embodiment, a PVA resin solution is applied on a base film to form a coating film, and a PVA layer is formed. The PVA layer is dyed to obtain a polarizing film. May be prepared by a solvent casting method or a melt extrusion method.

Hereinafter, the solvent casting method will be described in more detail.
When the PVA film is formed using the solvent casting method, the solvent, plasticizer, and the like that dissolve the polyvinyl alcohol-based resin can be those described in the above-mentioned [Production method of polarizing film].

The polyvinyl alcohol resin solution used in these methods is, for example, 80-9.
It can be obtained by dissolving a polyvinyl alcohol-based resin in water heated to 0 ° C.
The solid content concentration of the polyvinyl alcohol-based resin is preferably in the range of 6 wt% to 50 wt%. When the concentration of the solid content is less than 6 wt%, the viscosity becomes too low and the fluidity at the time of forming the resin layer becomes too high, and it becomes difficult to obtain a uniform film. On the other hand, the concentration of solids is 50
If it exceeds wt%, the viscosity becomes too high and the fluidity during the formation of the resin layer becomes low, so that film formation becomes difficult.

As a method of coating a polyvinyl alcohol resin solution on a support, roll coating methods such as wire bar coating method, reverse coating method and gravure coating, die coating method, comma coater method, lip coating method, spin coating method, screen Known methods such as a coating method, a fountain coating method, a dipping method, and a spray method can be appropriately selected and employed.

  In the solvent cast method, after a polyvinyl alcohol-based resin solution is applied on a support to form a resin layer, the resin layer formed on the support is dried at a low temperature to such an extent that it can be peeled off from the support, It is preferable to change the conditions and dry the resin layer peeled from the support. Hereinafter, the step of drying to such an extent that it can be peeled off from the support is referred to as “first drying step”, and the step of drying the resin layer peeled off from the support base is referred to as “second drying step”.

As a support body here, a release film, a stainless steel belt, a chill roll etc. are mentioned, for example.

  In the first drying step, “a degree that can be peeled off from the support” means that the solvent is removed from the applied resin solution to form a film-like coating film (hereinafter simply referred to as a film), and the film can be peeled off. is there. Empirically, it has been found that the film can be stably peeled if the moisture content of the film is dried to 30% by weight or less. Further, it is preferable that the moisture content of the film is dried to 20% by weight or less because it can be more easily peeled off.

  In addition, the moisture content said here is the ratio of the moisture contained in a film, and points out the value calculated | required by the dry weight method. The moisture content can be determined by the following method.

First, after leaving the peeled film at room temperature (approximately 25 ° C., 55% RH) for 30 minutes or more, the mass of the film is measured. The film is then dried in a 105 ° C. oven for 60 minutes. After removing from the oven, leave it for a few minutes until the temperature of the film returns to room temperature. The film mass is then remeasured.
Using the mass of the obtained film before drying (mass before drying) and the mass of the film after drying (mass after drying), the water content is obtained from the following formula.
Water content (%) = {(mass before drying) − (mass after drying)} / (mass before drying) × 100

  In the manufacturing process, it is preferable to set a drying condition in which the film can be peeled by performing a preliminary experiment and perform drying under the condition. For example, as a film drying condition, it is preferably dried for 1 to 30 minutes in a temperature range of 40 ° C. to 60 ° C., and more preferably 3 to 20 minutes at 50 ° C.

  In the first drying step, by drying at a low temperature, drying shrinkage is unlikely to occur in the film, and curling of the end portion can be prevented. Also, in the first drying step, the film is not completely dried, but is dried to such an extent that it can be peeled off from the support. it can.

  After the first drying step, the film is peeled from the support. Next, in the second drying step, the film is dried. In a 2nd drying process, conditions are changed from a 1st drying process and a film is fully dried. Specifically, in the second drying step, the film is dried at a higher drying temperature than in the first drying step.

  The drying temperature in the second drying step is preferably higher than the set temperature in the first drying step and 150 ° C. or lower. The drying temperature in the second drying step is more preferably 120 ° C. or less, and further preferably 100 ° C. or less. The drying temperature in the second drying step is more preferably 60 ° C. or higher, and further preferably 70 ° C. or higher.

  As a drying method that can be adopted in the second drying step, there are various methods such as a method of spraying hot air, a method of contacting with a hot roll, and a method of heating with an IR heater, all of which can be suitably used. The drying temperature in the first drying step and the second drying step is a drying facility in which a drying furnace is provided and drying is performed in a drying furnace, such as a method of blowing hot air or a method of heating with an IR heater. Means the ambient temperature in the drying equipment. In the case of contact-type drying equipment such as a hot roll, it means the surface temperature of the hot roll.

  As described above, a resin film can be produced by a melt casting method. The resin film produced by such a solvent casting method is a good one with curling suppressed.

  FIGS. 16-19 is sectional drawing which shows the manufacturing method of the polarizing film of 2nd Embodiment, and the manufacturing method of a polarizing plate.

  First, as shown in FIG. 16, the PVA film is stretched in the same manner as in the first embodiment to obtain a stretched film 41A. Further, a resin layer is formed on the surface of the stretched film 41A.

  At this time, in the present embodiment, the first resin layer 51 is formed on a part of the first surface 41a of the stretched film 41A, and at least the first resin layer 51 and the second surface 41b of the stretched film 41A are flat. The second resin layer 52 is formed at the overlapping position to obtain the laminated stretched film 61. As the forming material of the first resin layer 51 and the second resin layer 52, the same material as the resin layer 12 of the first embodiment can be used.

  The first resin layer 51 is provided based on the same idea as the resin layer 12A of the first embodiment. Therefore, the first resin layer 51 may be continuous in a ring shape, and the resin layer 51 is formed only at a position where cracks are likely to occur during cutting. The layer 51 may not be formed.

  The second resin layer 52 only needs to cover a position of the second surface 41b that overlaps at least the first resin layer 51 in a plane.

  Next, as shown in FIG. 17, the laminated stretched film 61 on which the resin layers 51 and 52 are formed is dyed with a dichroic dye. For example, as in FIG. 8 of the first embodiment, the dyeing is performed by immersing the laminated stretched film 61 in the dyeing solution in which the dichroic dye stored in the dyeing bath provided in the conveying path is dissolved. To do.

  At this time, in the stretched film 41A of the laminated stretched film 61, the regions AR1 and AR3 that are not protected by the resin layers 51 and 52 are dyed. On the other hand, the area AR2 protected by the resin layers 51 and 52 is less dyed than the areas AR1 and AR3. In FIG. 17, the dyed area 41x is the dyed area of the areas AR1 and AR3, and the non-dyed area 41y is the non-dyed area of the PVA layer AR2.

  In this way, a laminated stretched film 62 having a dyed stretched film 41B is obtained.

  Next, as shown in FIG. 18, the PVA resin of the stretched film 41B is crosslinked with a crosslinking agent. For example, as in FIG. 10 of the first embodiment, the cross-linking is performed by immersing in a cross-linking solution in which a cross-linking agent is dissolved in a cross-linking bath provided in the transport path while transporting the laminated stretched film 62.

  At this time, in the stretched film 41B of the laminated stretched film 62, the regions AR1 and AR3 that are not protected by the resin layers 51 and 52 are cross-linked. On the other hand, the area AR2 protected by the resin layers 51 and 52 is less likely to be cross-linked than the areas AR1 and AR3. FIG. 18 shows the PVA layers in the regions AR1 and AR3 that are cross-linked as the cross-linked region 11α, and the PVA layer in the region AR2 that is not dyed as the non-cross-linked region 11β.

In this way, a laminated stretched film 63 having a crosslinked PVA layer, that is, a polarizing film 41C is obtained. The obtained polarizing film 41 </ b> C has an absorption axis in the longitudinal direction of the laminated stretched film 63. The polarizing film 41C corresponds to the polarizing film in the present invention.
The manufacturing method of the polarizing film of this embodiment is as described above.

  The laminated stretched film 64 shown as sectional drawing of FIG. 19 is obtained by forming a laminated structure with respect to the obtained laminated stretched film 63 by the method shown in 1st Embodiment, or a well-known method. In addition, when the same thing as the base film 21 of 1st Embodiment is used as the 2nd resin layer 52, it is good to remove the 2nd resin layer 52 before formation of laminated structure.

Next, as illustrated in FIG. 19, the polarizing film 2 is formed by cutting the polarizing film 41 </ b> C along the resin layer 51 in the laminated stretched film 64. In FIG. 19, the cutting position is indicated by a dashed-dotted virtual line VR. As the cutting method, a method similar to the method shown in the first embodiment can be adopted.
The manufacturing method of the polarizing plate of this embodiment is as described above.

According to the polarizing plate having the above-described configuration, it is possible to provide a polarizing plate in which cracks at the peripheral portion are reduced.
Moreover, according to the manufacturing method of the above polarizing films, the manufacturing method of the polarizing film which can manufacture the above polarizing plates suitably can be provided.
Moreover, according to the manufacturing method of the above polarizing plates, the above polarizing plates can be manufactured suitably.

[Third Embodiment]
In the second embodiment, after the PVA film is stretched to obtain a stretched film, the resin layers are formed on both surfaces of the stretched film, but the present invention is not limited to this. As described below, a base film may be bonded to one surface of the stretched film, and a resin layer may be formed on the other surface.

  In the manufacturing method of the polarizing film of this embodiment, it has the process of obtaining the laminated body by which the stretched film by which the PVA film was extended | stretched was laminated | stacked on the surface of the strip | belt-shaped base film. Here, if a desired laminate is obtained, (i) after stretching the PVA film to obtain a stretched film, a laminate film may be obtained by pasting a base film on the obtained stretched film, (Ii) After bonding the PVA film and the base film, the whole may be stretched to obtain a laminate. Moreover, you may further extend | stretch the laminated body which bonded the base film to the stretched film.

  As a base film, the same thing as the base film 21 of 1st Embodiment can be used.

  After obtaining the laminate, the resin layer is formed on at least a part of the surface of the stretched film in the same manner as in FIGS. 6 and 7 of the first embodiment (step of forming the resin layer), and then the first embodiment. 8 to 11, the laminate on which the resin layer is formed is dyed with a dichroic dye, and the stretched film is crosslinked with a crosslinking agent to form a polarizer layer (step of forming a polarizer layer) ).

Then, the polarizing film of this embodiment can be manufactured by the method similar to the method shown in FIGS. 12-15 of 1st Embodiment.
The manufacturing method of the polarizing plate of this embodiment is as described above.

Even if it is the manufacturing method of the above polarizing films, the manufacturing method of the polarizing film which can manufacture suitably the polarizing plate with which the crack of the peripheral part was reduced can be provided.
Moreover, even if it is the manufacturing method of the above polarizing plates, the above polarizing plates can be manufactured suitably.

  FIG. 20 is a plan view showing an example of a deformed polarizing plate that can be suitably manufactured by the polarizing plate of the present invention and the manufacturing method of the polarizing plate. In the manufacturing method of the polarizing film of this invention, the polarizing film which can be used conveniently for manufacture of the deformed polarizing plate illustrated in FIG. 20 can be manufactured. In the figure, the absorption axis is indicated by a double-headed arrow with the symbol A.

  As shown in the figure, examples of the irregularly polarizing plate to which the present invention can be suitably applied include those having a peripheral edge extending in a direction intersecting with the absorption axis A at an angle other than orthogonal.

  Specifically, a circle (FIG. 20 (a)), an ellipse (FIG. 20 (b)), a shape with rounded corners (FIG. 20 (c)), and a cutout on the outer periphery of the rectangle. Rectangles (FIG. 20 (d)), pentagons (FIG. 20 (e)), triangles (FIG. 20 (f)), polygons other than squares, heart shapes (FIG. 20 (g)), lightning bolts ( A polarizing plate having a complicated shape such as that shown in FIG. 20 (h) can be exemplified as a polarizing plate that can be suitably manufactured according to the present invention. Moreover, as shown in FIG.20 (d), the polarizing plate which has the through-hole R can also be illustrated as a polarizing plate which can be manufactured suitably by this invention. Furthermore, the shape which combined 2 or more of these shapes may be sufficient. The shape which combined these shapes and the rectangular shape may be sufficient. The deformed polarizing plate illustrated in FIG. 20 is an example, and the present invention can be applied to any polarizing plate having a peripheral edge extending in a direction intersecting with the absorption axis A at an angle other than orthogonal.

  At the time of manufacturing such a polarizing plate, the present invention is applied, and the resin layer described above is provided at least in a peripheral portion extending in a direction intersecting at an angle other than orthogonal to the absorption axis A, and the position overlapping the resin layer In this case, it is preferable not to perform dyeing or crosslinking. Thereby, the polarizing plate obtained becomes a thing by which the crack of the peripheral part was reduced.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In this example,% and part representing the content or amount used are based on mass unless otherwise specified.

[Example 1]
(A) Base film preparation From a propylene / ethylene random copolymer (Sumitomo Noblen W151, manufactured by Sumitomo Chemical Co., Ltd., melting point: 138 ° C.) containing about 5% ethylene unit by coextrusion molding using a multilayer extrusion molding machine. A base film having a three-layer structure in which a resin layer made of a propylene homopolymer (Sumitomo Nobrene FLX80E4, manufactured by Sumitomo Chemical Co., Ltd., melting point 163 ° C.) was disposed on both surfaces of the resulting resin layer was prepared.
The total thickness of the obtained base film was 90 μm, and the thickness ratio (FLX80E4 / W151 / FLX80E4) of each layer was 3/4/3.

(B) Primer layer forming step PVA powder (Z-200, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) having an average degree of polymerization of 1100 and an average degree of saponification of 99.5 mol% is dissolved in hot water at 95 ° C, and the concentration is 3%. An aqueous solution of was prepared. In the obtained 3% PVA aqueous solution, as a crosslinking agent, a 30% aqueous solution of a water-soluble epoxy resin (Smileze Resin 650, manufactured by Taoka Chemical Co., Ltd.) was used at a ratio of 5 parts to 6 parts of the solid content of PVA. Mixing was performed to prepare a primer solution.

  One side of the base film was subjected to corona treatment, and the primer solution prepared above was applied to the corona-treated surface using a small-diameter gravure coater. The primer layer having a thickness of 0.2 μm was formed by drying at 80 ° C. for 10 minutes.

  Furthermore, the other surface of the base film was subjected to corona treatment, and similarly, a primer solution was applied and dried to produce a film having a primer layer formed on both sides of the base film.

(C) PVA layer forming step PVA powder (PVA124, manufactured by Kuraray Co., Ltd.) having an average degree of polymerization of 2400 and an average degree of saponification of 98.0 to 99.0 mol% was dissolved in hot water at 95 ° C, and the concentration was 8%. A polyvinyl alcohol aqueous solution was prepared. The obtained aqueous solution was applied to the surface of the primer layer formed on one side of the base film using a lip coater, and then continuously at 80 ° C. for 2 minutes, at 70 ° C. for 2 minutes, and A drying process was performed at 60 ° C. for 4 minutes to prepare a laminated film composed of two layers of a base film and a PVA layer.

  Next, the same coating and drying treatment were performed on the surface of the primer layer formed on the other surface of the base film to produce a laminated film in which the PVA layers were formed on both surfaces of the base film. In the obtained laminated film, the thicknesses of the PVA layers were 10.5 μm and 10.2 μm, respectively.

(D) Stretching Step A laminated stretched film was obtained by subjecting the laminated film to 5.8 times free end longitudinal uniaxial stretching at 160 ° C. using a roll-to-roll longitudinal stretcher. The thickness of the PVA layer after stretching was 5 μm ± 0.1 μm, respectively.

(E) Resin layer forming step On one PVA layer of the obtained laminated stretched film, a transparent ink I-067G (acrylic resin 10%, organic solvent 90%) is applied and solidified by an inkjet coating apparatus manufactured by Domino. To form a resin layer.

  As shown in FIG. 21 (a), the formed resin layer had a width of about 5 mm, a triangle of 100 mm in the film stretching direction (MD direction), 50 mm in the direction perpendicular to the stretching direction, and 112 mm in the oblique direction. When the vicinity of the boundary between the region where the resin layer was provided and the region where the resin layer was not provided was measured with a confocal laser microscope (PLμ NEOX, manufactured by SENSOFAR), the thickness of the resin layer was about 3 μm.

(F) Dyeing Step and Crosslinking Step The laminated stretched film on which the resin layer was formed was immersed in a dyeing solution at 30 ° C. for 140 seconds for dyeing treatment. Subsequently, the excess iodine solution was washed away with 10 ° C. pure water, and then immersed in a crosslinking solution at 76 ° C. for 600 seconds to carry out a crosslinking treatment. Thereby, the PVA layer was used as a polarizer layer. In this case, the piercing strength in the region where the resin layer was provided was not measurable because the breaking strength of the film was strong and did not break. The puncture strength in the region where no resin layer was provided was 5.5 g / μm.

<Dyeing solution>
Water: 100 parts Iodine: 0.35 parts Potassium iodide: 10 parts <Crosslinking solution>
Water: 100 parts Boric acid: 9.5 parts Potassium iodide: 5 parts

(H) Preparation of photocurable resin adhesive The following components were mixed and defoamed to prepare a liquid photocurable resin adhesive.
3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate: 75 parts 1,4-butanediol diglycidyl ether: 20 parts 2-ethylhexyl glycidyl ether: 5 parts Triarylsulfonium Hexafluorophosphate-based photocationic polymerization initiation Agent
: 2.25 parts

  The photocationic polymerization initiator used was obtained in the form of a 50% propylene carbonate solution. The amount (2.25 parts) shown above is the solid content.

(I) First protective film laminating step After laminating a protective film (Zeonor film (thickness 23 μm), manufactured by Nippon Zeon Co., Ltd.) coated with a photocurable resin adhesive on a dyed and cross-linked laminated stretched film, The photocurable resin composition was cured by irradiating ultraviolet rays so that the integrated light amount was 200 mJ / cm ² .

(J) Peeling process The laminated body of the polarizer layer and protective film in which the resin layer was formed was peeled from the laminated stretched film which bonded the protective film. The PVA layer (polarizer layer) of the obtained laminate had a region that was a transparent triangle and did not exhibit polarization performance.

(K) Second protective film bonding step A protective film (Zeonor film (thickness 23 μm), manufactured by Nippon Zeon Co., Ltd.) coated with a photocurable resin adhesive is bonded to the surface of the PVA layer of the obtained laminate. After that, the photocurable resin composition was cured by irradiating ultraviolet rays so that the integrated light amount was 200 mJ / cm ² .

(L) Adhesive bonding process Furthermore, the separate film with an adhesive was bonded to the bonded protective film.

(M) Film cutting step As shown in FIG. 21 (a), the obtained laminate is separated from the side of the separate film from the center of the resin layer (indicated by a one-dot chain line in the figure) along the resin layer. (PN1-600, manufactured by Hadano Seiki Seisakusho).

(N) Glass bonding process The separator on the pressure-sensitive adhesive side of the cut film was removed and bonded to glass (Eagle XG, manufactured by Corning) with a roller to prepare Evaluation Sample 1.

[Example 2]
As shown in FIG. 21 (b), the resin layer has a circular shape with a diameter of about 10 mm, a circular hole with a diameter of 6 mm is formed at the center of the resin layer, and the periphery is 5 cm in the direction perpendicular to the stretching direction. An evaluation sample 2 was prepared in the same manner as in Example 1 except that it was cut with a super cutter (PN1-600, manufactured by Hadano Seiki Seisakusho) to about 10 cm in the stretching direction.

[Example 3]
Instead of the transparent ink I-067G, a 10% solution obtained by diluting the above-described photocurable resin adhesive with methyl ethyl ketone was used. Evaluation sample 3 was prepared in the same manner as in Example 2 except that the 10% solution was dropped with a dropper to form a circular resin layer having a diameter of about 20 mm. The film thickness of the resin layer was about 5 μm.

[Comparative Example 1]
An evaluation sample 4 of Comparative Example 1 was produced in the same manner as in Example 1 except that the resin layer was not formed.

[Comparative Example 2]
An evaluation sample 5 of Comparative Example 2 was produced in the same manner as in Example 2 except that no resin layer was formed.

[Check puncture strength]
The piercing test was performed by fixing a polarizer to a small tabletop testing machine (trade name “EZ Test” manufactured by Shimadzu Corporation) equipped with a piercing jig having a diameter of 1 mm and a curvature radius of 0.5 R at the tip.
The measurement was performed under the conditions of a puncture speed of 0.33 cm / sec in an environment with a temperature of 23 ± 3 ° C. The puncture strength measured in the puncture test was a puncture test performed on 12 test pieces, and the average value was obtained. The thickness of the polarizer was measured with a contact-type film thickness meter (trade name “DIGIMICRO MH-15M” manufactured by Nikon Corporation), and the puncture strength per unit film thickness was determined.

[Confirmation of cracks during cutting of polarizing plate]
Using a digital microscope “VHX-500” manufactured by Keyence Corporation, the ends (cut portions) of the polarizing plates obtained in the examples and comparative examples were observed, and cracks in the polarizer layer were confirmed. The evaluation results are shown in Table 1 below.

  As a result of the evaluation, no cracks could be confirmed in any of Examples 1 to 3. On the other hand, cracks were confirmed in Comparative Examples 1 and 2.

  From the above results, it was confirmed that the present invention is useful.

  DESCRIPTION OF SYMBOLS 1,11 ... Polarizer layer, 1,2 ... Polarizing plate, 11 (alpha) ... Bridge | crosslinking area | region, 11 (beta) ... Non-crosslinking area | region, 11a, 41a ... 1st surface, 11b, 41b ... 2nd surface, 11D, 41C ... Polarizing film , 12, 12A ... resin layer, 13, 13A, 15, 15A ... adhesive layer, 14, 14A, 16, 16A ... protective layer, 19 ... coating film, 21, 21A, 21B ... substrate film, 30, 31 ... Laminated film, 32, 32B, 33, 34, 35, 61, 62, 63, 64 ... laminated stretched film, 41A, 41B ... stretched film, 51 ... first resin layer, 52 ... second resin layer

Claims (10)

A polarizer layer in which a polyvinyl alcohol resin is used as a forming material and a dichroic dye is adsorbed and oriented;
In the first surface of the polarizer layer, a resin layer provided on at least a part of the peripheral portion of the first surface;
An adhesive layer that overlaps with the resin layer in a planar manner and covers the entire surface of the first surface;
A protective layer that overlaps the adhesive layer in a plan view and covers the entire surface of the first surface;
The polarizer layer has a cross-linked region in which the polyvinyl alcohol-based resin is cross-linked with a cross-linking agent, and a non-cross-linked region in which cross-linking by the cross-linking agent does not proceed more than the cross-linked region,
The non-crosslinked region is a polarizing plate provided so as to overlap the resin layer in a planar manner.   The polarizing plate according to claim 1, wherein the resin layer is made of a photocurable resin. The thickness of the polarizer layer in the crosslinked region is equal to the thickness of the polarizer layer in the non-crosslinked region,
The polarizing plate according to claim 1, wherein a thickness of the resin layer is not more than twice a thickness of the polarizer layer.   The polarizing plate according to claim 1, wherein the polarizer layer has a thickness of 10 μm or less. Coating the surface of the belt-shaped substrate film with a polyvinyl alcohol resin solution to obtain a laminated film;
Stretching the base film and a polyvinyl alcohol-based resin layer formed on the surface of the base film together to obtain a laminated stretched film;
In the layer of the polyvinyl alcohol resin in the laminated stretched film, a step of forming a resin layer on at least a part of the surface of the layer;
A method of producing a polarizing film comprising: a step of dyeing a laminated stretched film having the resin layer formed thereon with a dichroic dye, and crosslinking the polyvinyl alcohol resin with a crosslinking agent to form a polarizer layer. Stretching a polyvinyl alcohol resin film to obtain a stretched film;
Forming a resin layer on the stretched film;
The laminated stretched film on which the resin layer is formed is dyed with a dichroic dye, and the polyvinyl alcohol resin is crosslinked with a crosslinking agent to form a polarizer layer, and
In the step of forming the resin layer, the first resin layer is formed on a part of the first surface of the stretched film, and at least overlaps the first resin layer on the second surface of the stretched film. The manufacturing method of the polarizing film which forms a 2nd resin layer in a position. A step of obtaining a laminate in which a stretched film obtained by stretching a polyvinyl alcohol-based resin film is laminated on the surface of a belt-like base film;
In the layer of the stretched film in the laminate, a step of forming a resin layer on at least a part of the surface of the layer;
A method for producing a polarizing film comprising: a step of dyeing a laminate on which the resin layer is formed with a dichroic dye, and crosslinking the stretched film with a crosslinking agent to form a polarizer layer.   The said resin layer manufactures the polarizing film of any one of Claim 5 to 7 formed by volatilizing the said organic solvent after apply | coating the solution which dissolved the forming material of the said resin layer in the organic solvent. Method.   The said resin layer is a manufacturing method of the polarizing film of any one of Claim 5 to 7 formed by light-irradiating after forming the coating film of the photocurable resin which is the formation material of the said resin layer. A step of producing a polarizing film by the method for producing a polarizing film according to any one of claims 5 to 9,
A step of cutting the polarizing film along the resin layer.

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