JP7412231B2 - optical laminate - Google Patents

Description

The present invention relates to an optical laminate.

Polarizing layers, retardation layers, and the like are widely used as optical members constituting organic EL display devices and liquid crystal display devices using organic light emitting diodes (OLEDs). For example, Patent Document 1 describes that a composite polarizing plate in which a polarizer and a retardation film coated with a liquid crystal compound are laminated is used in a liquid crystal display device.

Patent Document 1 discloses that by eliminating unevenness that exists on the outer peripheral end surface (cut surface) when a composite polarizing plate is cut by chip cutting etc., defects such as peeling and lifting of the retardation film are suppressed even under humid heat conditions. It describes what you can do.

Japanese Patent Application Publication No. 2008-9237

When a composite polarizing plate made by laminating a polarizing layer and a retardation film is exposed to external light including ultraviolet rays, the hue of the reflected light at the edges of the composite polarizing plate changes, and the uniformity of the hue of the reflected light within the plane changes. It was found that it got worse.

An object of the present invention is to provide an optical laminate that can suppress deterioration in the uniformity of the hue of reflected light within a surface even when exposed to external light including ultraviolet rays.

The present invention provides the following optical laminate.
[1] An optical laminate comprising a polarizing layer, an adhesive layer, and a first retardation layer in this order,
The first retardation layer is a liquid crystal layer,
The optical laminate has an adhesive missing portion at an end in the surface direction,
In a cross section passing through a portion where the first retardation layer and the adhesive layer overlap in the lamination direction, the adhesive chipping portion is such that the position of the innermost end of the end of the adhesive layer is at the first retardation layer. An optical laminate formed so as to be located within a range of more than 0 μm and 10 μm or less from the outermost position of the end of the layer.
[2] The optical laminate has a rectangular shape or a rectangular shape having a notch on at least one side,
The optical laminate according to [1], wherein the adhesive missing portion is formed on at least one side of a rectangular shape.
[3] The rectangular shape has a pair of long sides and a pair of short sides,
The absorption axis direction of the polarizing layer forms an angle of 45° ± 10° with respect to the long side,
The optical laminate according to [2], wherein the adhesive missing portion is formed on at least one of the pair of long sides and at least one of the pair of short sides.
[4] The rectangular shape has a pair of long sides and a pair of short sides,
The absorption axis direction of the polarizing layer makes an angle of 0° ± 10° with respect to the long side,
The optical laminate according to [2], wherein the adhesive missing portion is formed on at least one of the pair of short sides.
[5] The rectangular shape has a pair of long sides and a pair of short sides,
The absorption axis direction of the polarizing layer makes an angle of 0° ± 10° with respect to the short side,
The optical laminate according to [2], wherein the adhesive missing portion is formed on at least one of the pair of long sides.
[6] In the adhesive layer in the adhesive chipping part, the position of the end on the first retardation layer side is outward in the plane direction from the position of the end on the surface of the polarizing layer. The optical laminate according to any one of [5].
[7] The optical laminate according to any one of [1] to [6], which has a protective layer on one or both sides of the polarizing layer.
[8] The optical laminate according to any one of [1] to [7], further comprising a second retardation layer on the opposite side of the first retardation layer from the adhesive layer.
[9] The optical laminate according to [8], wherein the second retardation layer is provided on the first retardation layer via an adhesive layer.
[10] The optical laminate according to any one of [1] to [9], wherein the adhesive layer contains an ultraviolet absorber.
[11] The optical laminate according to any one of [1] to [10], which is a circularly polarizing plate.

According to the present invention, it is possible to provide an optical laminate that can suppress deterioration of the uniformity of the hue of reflected light within a surface even when exposed to external light including ultraviolet rays.

FIG. 1 is a cross-sectional view schematically showing an example of an optical laminate of the present invention. FIG. 3 is a cross-sectional view schematically showing another example of the optical laminate of the present invention. (a) and (b) are schematic diagrams for explaining a method for producing an adhesive layer in an example.

Hereinafter, preferred embodiments of the optical laminate of the present invention will be described with reference to the drawings. Note that the scope of the present invention is not limited to the embodiments described here, and various changes can be made without departing from the spirit of the present invention.

FIG. 1 is a cross-sectional view schematically showing an example of the optical laminate of this embodiment. In the figure, W represents the surface direction. As shown in FIG. 1, the optical laminate 11 of this embodiment includes a polarizing plate 40, an adhesive layer 31, and a first retardation layer 21 in this order. The polarizing plate 40 of the optical laminate 11 shown in FIG. 1 has a first protective layer 42 (protective layer), a polarizing layer 41, and a second protective layer 43 (protective layer) in this order. An adhesive layer 31 is provided on the first protective layer 42 side.

The polarizing layer 41 may be a polyvinyl alcohol resin film (hereinafter sometimes referred to as "PVA resin film") in which a dichroic dye such as iodine is adsorbed and oriented. The film is typically a stretched polyvinyl alcohol resin film. The polarizing layer 41 may be a layer in which a liquid crystal compound is hardened and dichroic dyes are oriented therein. The first protective layer 42 and the second protective layer 43 are layers for protecting the polarizing layer 41. The first retardation layer 21 is a liquid crystal layer containing a liquid crystal compound. The liquid crystal layer can be, for example, a cured layer formed by polymerizing a polymerizable liquid crystal compound. The optical laminate 11 may have an alignment layer on the opposite side of the first retardation layer 21 from the adhesive layer 31 for orienting the liquid crystal compound forming the first retardation layer 21 .

The optical laminate 11 has an adhesive missing portion 5 at an end in the surface direction W thereof. As shown in FIG. 1, the adhesive chipping portion 5 is located at the end of the adhesive layer 31 in a cross section passing through a portion where the first retardation layer 21 and the adhesive layer 31 overlap in the lamination direction perpendicular to the surface direction W. The innermost end position of the first retardation layer 21 is located inward within a distance L1 from the outermost end position of the end portion of the first retardation layer 21 . In this specification, the innermost position of the end of the adhesive layer 31 refers to the innermost position in the surface direction W of the end of the adhesive layer 31, and the end of the first retardation layer 21. The outermost position in the section refers to the outermost position in the surface direction W among the ends of the first retardation layer 21 .

The distance L1 of the glue chipping portion 5 is more than 0 μm, may be 0.2 μm or more, may be 0.5 μm or more, may be 2 μm or more, and is 10 μm or less, and may be 8 μm. It is preferably below, and may be 5 μm or less, or may be less than 5 μm.

The first retardation layer 21 included in the optical laminate 11 is a liquid crystal layer containing a liquid crystal compound. It is presumed that the first retardation layer 21 of such a liquid crystal layer is likely to deteriorate when exposed to external light including ultraviolet rays during use of the optical laminate 11 because the liquid crystal compound is an organic compound. When the first retardation layer 21 deteriorates, the retardation characteristics originally possessed by the first retardation layer 21 are lost, and the hue of the reflected light from the optical laminate 11 is considered to change. When applying the optical laminate 11 to a display device or the like, the first retardation layer 21 side is usually the display device side, and the polarizing plate 40 side is exposed to the outside, so the polarizing plate 40 side of the first retardation layer 21 is exposed to ultraviolet rays. Easily exposed to external light, including In this embodiment, by setting the distance L1 at the adhesive chipping portion 5 of the optical laminate 11 to 10 μm or less, the area not covered by the adhesive layer 31 is reduced as much as possible. This suppresses deterioration of the first retardation layer 21 due to external light, and prevents deterioration of the uniformity of the hue of reflected light within the plane even when the optical laminate 11 is exposed to external light. It is assumed that this can be suppressed.

The distance L1 of the adhesive chipping portion 5 is determined by measuring the cross-sectional profile of the optical laminate 11 using a laser microscope, and determining the innermost position at the end of the adhesive layer 31 based on this profile. Further, it can be calculated based on the position of the outermost end of the end portion of the first retardation layer 21 . If the outer shape of the optical laminate 11 has a linear side and an adhesive chipping part 5 is formed on the side, the cross section of the optical laminate 11 has a linear side. The cross section is taken along the direction perpendicular to the side at the position where the cross section is located. Further, when the outer shape of the optical laminate 11 has a curved portion and the adhesive chipped portion 5 is formed in the curved portion, the cross section of the optical laminate 11 is located at the position where the glue chipped portion 5 is formed. The cross section is taken along a direction that passes through the position P of a tangent to the surface direction of the optical laminate 11 at point P and is perpendicular to the tangent.

The shape of the adhesive chipping part 5 in the optical laminate 11 is not particularly limited, and the end of the adhesive layer 31 may have a tapered shape as shown in FIG. It may be parallel to the direction, or may be formed in a sawtooth shape, an uneven shape, a curved shape, etc. As shown in FIG. 1, in the adhesive layer 31 in the adhesive chipped portion 5, the position of the end of the surface of the adhesive layer 31 on the first retardation layer 21 side is the same as the position of the end of the surface of the adhesive layer 31 on the polarizing plate 40 side. It is preferable that it is on the outside in the plane direction, and it is more preferable that the shape is tapered. This makes it possible to reduce the area of the exposed surface of the first retardation layer 21 where the adhesive layer 31 is not provided at the end of the first retardation layer 21, so that the optical laminate 11 can be removed from the outside. It is thought that when exposed to light, deterioration in the uniformity of the hue of reflected light within the surface can be easily suppressed.

The outer shape of the optical laminate 11 can be a rectangle in the surface direction (planar view) or a rectangle having a notch on at least one side. In this specification, a rectangular shape refers to a rectangular shape or a square shape, and includes a rectangular shape in which at least one of the four corners is rounded. Note that the boundary between two consecutive sides via a rounded corner is a position that bisects the contour length of the rounded corner. The outline length of the rounded corner portion is defined as the length between the ends of the straight line portions of two consecutive sides that are located on the rounded portion side. Examples of the notch include a concave shape that becomes concave toward the opposing sides, and the concave shape may be U-shaped or V-shaped. The notch portion may be formed on one side of the rectangular shape, or may be formed on two or more sides. The notch can be provided in a region where at least one of an earpiece, a speaker, a camera lens, an LED lamp, a proximity sensor, an illuminance sensor, a fingerprint authentication sensor, an operation button, etc. is installed in, for example, a smartphone or the like.

When the optical laminate 11 has a rectangular shape, the adhesive chipping portion 5 is preferably formed on at least one side of the rectangular shape, may be formed on two or more sides, or may be formed on all four sides. good. Further, the adhesive chipping portion 5 may be formed continuously or discontinuously over the entire length of the side, or may be formed on a part of the side. When the adhesive chipping portion 5 is continuously formed on the side, it is preferable that the area where the adhesive chipping portion 5 is continuously formed is included in 50% or more of the total length of the side, and the area is the area that is the length of the total length of the side. It is more preferably 70% or more, and even more preferably 90% or more. If the glue chipping portion 5 is formed continuously over the above range, the change in the hue of the reflected light tends to be noticeable, but in the optical laminate 11, the adhesive chipping portion 5 is formed continuously as described above. Since the distance L1 is 10 μm or less, it is possible to suppress changes in the hue of reflected light at the ends. Thereby, even when the optical laminate 11 is exposed to external light, deterioration in the uniformity of the hue of reflected light within the plane can be easily suppressed.

The optical laminate 11 may have a hole that penetrates the entire optical laminate 11 in the stacking direction. The hole may have a circular shape, or a polygonal shape such as an elliptical shape, a quadrangular shape, or a hexagonal shape, and at least one corner of the polygonal shape may be rounded. An adhesive missing portion 5 may be formed around the hole. The adhesive missing portion formed in the hole may be formed in at least a portion of the circumferential portion of the hole, or may be formed in the entire circumferential portion of the hole. The hole can be provided, for example, in a region where a camera lens or the like is installed in a smartphone or the like.

The optical laminate 11 has a rectangular shape, and this square shape is a rectangle having a pair of long sides and a pair of short sides, and the absorption axis direction of the polarizing layer 41 is at an angle of 45°±10° with respect to the long sides. When forming an angle, it is preferable that the adhesive chipped portion 5 is formed on at least one of the pair of long sides and at least one of the pair of short sides. In this specification, the above-mentioned angle refers to an acute angle among the angles formed between the absorption axis direction and the long side. The adhesive missing portion 5 may be formed on both of the pair of long sides, or may be formed on both of the pair of short sides. The polarizing layer 41 of the optical laminate 11 may expand and contract in the absorption axis direction due to environmental changes such as changes in humidity. In this case, the polarizing layer 41 expands and contracts at the sides located at both ends in the absorption axis direction. Stress tends to concentrate. Therefore, in the optical laminate 11 in which the absorption axis direction and the long sides have a relationship of 45°±10°, the expansion and contraction stress of the polarizing layer 41 is concentrated on both the long sides and the short sides, and the stress of the first retardation layer 21 is concentrated. It is thought that the hue of the reflected light is likely to change. As described above, by providing the adhesive missing portion 5 on at least one of the pair of long sides and at least one of the pair of short sides, even when the polarizing layer 41 of the optical laminate 11 expands or contracts, the polarizing layer 41 It is possible to disperse the stretching stress in a portion where the stretching stress tends to be concentrated. It is thought that this makes it possible to effectively suppress deterioration in the uniformity of the hue of reflected light within the plane even when the polarizing layer 41 expands and contracts. The angle that the absorption axis direction of the polarizing layer 41 makes with respect to the long side may be 45°±5°, 45°±2°, or 45°.

The optical laminate 11 has a rectangular shape, and this square shape is a rectangle having a pair of long sides and a pair of short sides, and the absorption axis direction of the polarizing layer 41 is at an angle of 0°±10° with respect to the long sides. When forming an angle, it is preferable that the adhesive missing portion 5 is formed on at least one of the pair of short sides. In this specification, the above-mentioned angle refers to an acute angle among the angles formed between the absorption axis direction and the long side. The adhesive missing portion 5 may be formed on both of the pair of short sides. In the optical laminate 11 in which the absorption axis direction and the long sides have a relationship of 0°±10°, for the above-mentioned reasons, the expansion and contraction stress of the polarizing layer 41 tends to concentrate on the short sides, and the reflection of the first retardation layer 21 It is thought that the hue of the light changes easily. Therefore, we believe that by providing the adhesive chipping portion 5 on at least one of the pair of short sides, it is possible to effectively suppress the deterioration of the uniformity of the hue of reflected light within the plane even when the polarizing layer 41 expands and contracts. It will be done. The angle that the absorption axis direction of the polarizing layer 41 makes with respect to the long side may be 0°±5°, 0°±2°, or 0°.

The optical laminate 11 has a rectangular shape, and this rectangular shape has a pair of long sides and a pair of short sides, and the absorption axis direction of the polarizing layer 41 is at an angle of 0°±10° with respect to the short sides. When forming an angle, it is preferable that the adhesive chipping portion 5 is formed on at least one of the pair of long sides. In this specification, the above-mentioned angle refers to an acute angle among the angles formed between the absorption axis direction and the short side. The adhesive missing portion 5 may be formed on both of the pair of long sides. In the optical laminate 11 in which the absorption axis direction and the short sides have a relationship of 0°±10°, for the above-mentioned reasons, the expansion and contraction stress of the polarizing layer 41 tends to concentrate on the long sides, and the reflection of the first retardation layer 21 It is thought that the hue of the light changes easily. Therefore, we believe that by providing the adhesive chipping portion 5 on at least one of the pair of long sides, it is possible to effectively suppress the deterioration of the uniformity of the hue of the reflected light within the plane even when the polarizing layer 41 expands and contracts. It will be done. The angle that the absorption axis direction of the polarizing layer 41 makes with respect to the short side may be 0°±5°, 0°±2°, or 0°.

It is preferable that the adhesive layer 31 contains an ultraviolet absorber. By including the ultraviolet absorber in the region of the first retardation layer 21 covered by the adhesive layer 31, deterioration of the first retardation layer 21 due to external light can be further suppressed. Therefore, when the optical laminate 11 is exposed to external light, the uniformity of the hue of reflected light within the plane can be made more difficult to deteriorate.

In the optical laminate 11 shown in FIG. 1, the first retardation layer 21 may be an A plate or a C plate. Further, in the optical laminate 11 shown in FIG. 1, the first retardation layer 21 can be a circularly polarizing plate by using a quarter wavelength plate.

For example, the optical laminate 11 shown in FIG. It can be manufactured by applying or transferring an adhesive to at least one side and bonding the polarizing plate 40 and the first retardation layer 21 through the adhesive layer. When the first retardation layer 21 is a liquid crystal layer, the first retardation layer 21 is a first retardation layer with a base material layer in which the first retardation layer 21 is removably formed on the first base material layer. , and the polarizing plate 40 may be laminated via an adhesive, and then the first base layer may be peeled off.

The method for forming the adhesive chipping portion 5 in the optical laminate 11 is not particularly limited, but can be formed by, for example, adjusting the application range and transfer position of the adhesive layer for forming the adhesive layer 31. . When the adhesive layer 31 is formed by transfer, a portion that will become the adhesive chipped portion 5 is formed in the adhesive layer formed on a release film or the like prepared for transfer, and a portion that will become the adhesive chipped portion 5 is formed in advance. The adhesive layer on which the portions have been formed may be transferred onto the polarizing plate 40 or the first retardation layer 21.

In order to form the adhesive chipped portion 5 on the adhesive layer formed on the release film or the like, for example, as shown in FIGS. 3A and 3B, the adhesive layer 61 is formed on the release film 62. It can be formed by preparing the adhesive layer 60 with a release film formed thereon, and cutting the adhesive layer 60 with a release film from the adhesive layer 61 side using a single-edged cutting blade 65. In the process of cutting the adhesive layer 60 with a release film in this way, the adhesive layer 61 can be pushed into a tapered shape by the side on which the blade is formed of both sides of the single-edged cutting blade 65. , it is possible to form the adhesive layer 31 with tapered ends.

(Modified example)
The optical film of this embodiment may be modified as shown in the following modifications, and the structures and steps of the embodiment and its modifications may be implemented in combination.

(Modification 1)
In the above embodiment, the optical laminate 11 has been described which includes the polarizing plate 40 having the first protective layer 42 and the second protective layer 43 on both sides of the polarizing layer 41, but the present invention is not limited thereto. The polarizing plate may include the polarizing layer 41 and either the first protective layer 42 or the second protective layer 43. Further, the first protective layer 42 and the second protective layer 43 may not be included in the optical laminate 11.

(Modification 2)
When the optical laminate 11 shown in FIG. 1 is a circularly polarizing plate, this circularly polarizing plate can be used, for example, for antireflection in an organic electroluminescence (organic EL) display device. In this case, the optical laminate 11 is used by being attached to the viewing side of the optical display element of the organic EL display device. Therefore, the optical laminate 11 may have an optical display element adhesive layer for bonding to an optical display element on the side opposite to the adhesive layer 31 of the first retardation layer 21.

(Modification 3)
In the above embodiment, the optical laminate 11 including the first retardation layer 21 has been described, but the optical laminate 11 is not limited thereto, and may be an optical laminate shown in FIG. 2, for example. FIG. 2 is a cross-sectional view schematically showing another example of the optical laminate of this embodiment. In the following, the same reference numerals are given to the same members as those explained above, and the explanation thereof will be omitted. The optical laminate 12 shown in FIG. 2 has a polarizing plate 40, an adhesive layer 31, a first retardation layer 21, an adhesive layer 35, and a second retardation layer 22 in this order. The adhesive layer 35 may be an adhesive layer formed using an adhesive, or may be an adhesive layer formed using an adhesive. The second retardation layer 22 may be a retardation film, or may be a liquid crystal layer containing a liquid crystal compound such as a polymerizable liquid crystal compound. When the second retardation layer 22 is a liquid crystal layer, the optical laminate 12 has an orientation for aligning the liquid crystal compound forming the second retardation layer 22 on the side opposite to the adhesive layer 35 of the second retardation layer 22. It may have layers.

In the optical laminate 12, the first retardation layer 21 is a 1/2 wavelength plate, and the second retardation layer 22 is a 1/4 wavelength plate; the first retardation layer 21 is a 1/4 wavelength plate with reverse wavelength dispersion. A wavelength plate, and the second retardation layer 22 is a positive C plate; the first retardation layer 21 is a positive C plate, and the second retardation layer 22 is a quarter wavelength plate with reverse wavelength dispersion. , a circularly polarizing plate. When the combination of the first retardation layer 21 and the second retardation layer 22 is a half-wave plate and a quarter-wave plate, the half-wave plate has a slow phase with respect to the absorption axis direction of the polarizing layer 41. The axial direction can be set at 70° to 80°, and the slow axis direction of the quarter-wave plate can be set at 10° to 20°. Further, when the combination of the first retardation layer 21 and the second retardation layer 22 is a reverse wavelength dispersion 1/4 wavelength plate and a positive C plate, 1/4 with respect to the absorption axis direction of the polarizing layer 41 The slow axis direction of the wave plate can be set at 40° to 50°. When the optical laminate 12, which is a circularly polarizing plate, is used for antireflection in an organic EL display device, the optical laminate 12 shown in FIG. It may have an adhesive layer for optical display elements.

The optical laminate 12 shown in FIG. 2 includes, for example, a retardation layer laminate in which a first retardation layer 21 and a second retardation layer 22 are laminated via an adhesive layer 35, and a polarizing plate 40, An adhesive is applied or transferred to at least one of the first protective layer 42 side of the polarizing plate 40 and the first retardation layer 21 side of the retardation layer laminate, and the polarizing plate 40 and the retardation layer laminate are bonded together. It can be formed by bonding them together via an adhesive. When both the first retardation layer 21 and the second retardation layer 22 are liquid crystal layers, the optical laminate 12 can be obtained, for example, as follows. First, the first retardation layer 21 of the first retardation layer with a base material layer in which the first retardation layer 21 is removably formed on the first base material layer, and the first retardation layer 21 removably formed on the second base material layer. The second retardation layer 22 of the second retardation layer with a base material layer formed with the two retardation layers 22 is laminated via an adhesive layer to obtain a retardation layer laminate. Next, the first base material layer is peeled off from this retardation layer laminate, and the first retardation layer 21 side and the first protective layer 42 side of the polarizing plate 40 are laminated with an adhesive interposed therebetween. By peeling off the two base material layers, an optical laminate 12 shown in FIG. 2 can be obtained.

Hereinafter, each matter common to the above-described embodiment and its modified examples will be described in detail.

(polarizing layer)
The polarizing layer may be a polyvinyl alcohol resin film (hereinafter sometimes referred to as "PVA resin film") in which a dichroic dye such as iodine is adsorbed and oriented, and the liquid crystal compound is cured. The dichroic dye may be oriented in the layer.

A PVA-based resin film is a film formed using polyvinyl alcohol-based resin. The polyvinyl alcohol resin refers to a resin containing 50% by mass or more of constitutional units derived from vinyl alcohol. As the polyvinyl alcohol resin, a saponified polyvinyl acetate resin can be used. The degree of saponification of the polyvinyl acetate resin can be determined according to JIS K 6727 (1994), and can be, for example, in the range of 80.0 to 100.0 mol%.

Examples of the polyvinyl acetate-based resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and a copolymer of vinyl acetate and other monomers copolymerizable therewith. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth)acrylamides having an ammonium group. In this specification, "(meth)acrylic" represents at least one selected from the group consisting of acrylic and methacryl. The same applies to other terms with "(meta)" added.

An example of the PVA resin film may be an unstretched film made of polyvinyl alcohol resin, or a stretched film obtained by stretching this unstretched film. When the PVA-based resin film is a stretched film, it is preferably a stretched film that has been longitudinally uniaxially stretched, and preferably a stretched film that has been dry stretched. When the PVA-based resin film is a stretched film, the stretching ratio is usually 1.1 to 8 times.

Examples of dichroic dyes adsorbed and oriented on the PVA-based resin film include iodine and organic dyes. Examples of 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, Splat Blue G, Splat Blue GL, Splat Orange GL, Direct Sky Blue, Examples include Direct First Orange S and First Black. One type of dichroic dye may be used alone, or two or more types may be used in combination.

A polarizing layer in which a dichroic dye is oriented in a layer made of a cured liquid crystal compound may be, for example, a cured layer in which a dichroic dye is oriented in a polymerizable liquid crystal compound and the polymerizable liquid crystal compound is polymerized. The following can be mentioned. Such a polarizing layer is formed by applying a polarizing layer forming composition containing a liquid crystal compound and a dichroic dye onto a base film, and polymerizing and curing the liquid crystal compound while maintaining the liquid crystal state. Can be done. The polarizing layer thus obtained is in a state of being laminated on a base film, and the base film may be used as it is as a protective layer for the polarizing layer. Alternatively, the base film may be peeled off after a polarizing layer with a base film in which the base film can be peeled off from the polarizing layer is laminated on the first retardation layer via the adhesive layer 31.

The liquid crystal compound only needs to have the property of exhibiting a liquid crystal state, and it is particularly preferable to have a high-order alignment state such as a smectic phase because it can exhibit high polarization performance. Moreover, it is also preferable that the liquid crystal compound has a polymerizable functional group. A dichroic dye is a dye that exhibits dichroism when aligned with a liquid crystal compound, and the dichroic dye itself may have liquid crystal properties or may have a polymerizable functional group. can. Any compound in the composition for forming a polarizing layer containing a liquid crystal compound has a polymerizable functional group.

Examples of dichroic dyes that can be used in the polarizing layer using a liquid crystal compound include acridine dyes, oxazine dyes, cyanine dyes, naphthalene dyes, azo dyes, and anthraquinone dyes, among which azo dyes are preferred. Examples of the azo dye include monoazo dyes, bisazo dyes, trisazo dyes, tetrakisazo dyes, and stilbene azo dyes, with bisazo dyes and trisazo dyes being more preferred. One type of dichroic dye may be used alone, or two or more types may be used in combination.

The composition for forming a polarizing layer includes a solvent, a polymerization initiator such as a photopolymerization initiator, a photosensitizer, a polymerization inhibitor, a dispersant, a leveling agent, a stabilizer, a surfactant, a crosslinking agent, a silane coupling agent, etc. can include. As for the polymerizable liquid crystal compound, dichroic dye, solvent, polymerization initiator, photosensitizer, polymerization inhibitor, etc. contained in the composition for forming a polarizing layer, known ones can be used. Further, the polymerizable liquid crystal compound may be the same as the compound exemplified as the polymerizable liquid crystal compound used to obtain the first retardation layer and the second retardation layer described later.

The thickness of the polarizing layer 41 is usually 2 to 40 μm, and from the viewpoint of making the polarizing layer thinner, it is preferably 30 μm or less, and more preferably 20 μm or less. The polarizing layer, which is a layer in which a dichroic dye is oriented in a liquid crystal compound, can be formed with a smaller thickness than the polarizing layer in which a dichroic dye, such as iodine, is adsorbed and oriented on a PVA-based resin film. The thickness of the polarizing layer using a liquid crystal compound may be, for example, 0.5 to 5 μm, preferably 1 to 4 μm.

Further, the visibility correction single transmittance Ty of the polarizing layer 41 is preferably 40 to 47%, more preferably 41 to 45%, taking into account the balance with the visibility correction polarization degree Py. The visibility correction polarization degree Py is preferably 99.9% or more, more preferably 99.95% or more. Ty and Py can be determined by using an absorbance photometer with an integrating sphere and performing visibility correction on the obtained transmittance and degree of polarization using a 2-degree field of view (C light source) according to JIS Z 8701.

(Polarizer)
A polarizing plate is one in which a protective layer (first protective layer, second protective layer) is laminated on one or both sides of a polarizing layer via a known pressure-sensitive adhesive layer or adhesive layer. The thickness of the polarizing plate can be, for example, 2 μm or more and 300 μm or less, and may be 10 μm or more, and may be 150 μm or less, 120 μm or less, or 80 μm or less. .

As the protective layer, for example, a film formed from a thermoplastic resin having excellent transparency, mechanical strength, thermal stability, moisture barrier properties, isotropy, stretchability, etc. is used. Specific examples of such thermoplastic resins include cellulose resins such as triacetylcellulose; polyester resins such as polyethylene terephthalate and polyethylene naphthalate; polyethersulfone resins; polysulfone resins; polycarbonate resins; polyamides such as nylon and aromatic polyamides. Resin; Polyimide resin; Polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymers; Cyclic polyolefin resins having cyclo- and norbornene structures (also referred to as norbornene-based resins); (meth)acrylic resins; Polyarylate resins; Polystyrene resins ; Polyvinyl alcohol resins and mixtures thereof can be mentioned. When protective layers are laminated on both sides of the polarizing layer, the resin compositions of the two protective layers may be the same or different. The film formed from a thermoplastic resin may be subjected to surface treatment (for example, corona treatment, etc.) in order to improve adhesion with the polarizing layer, and a thin layer such as a primer layer (also referred to as an undercoat layer) may be applied. may be formed.

The protective layer may be, for example, a stretched thermoplastic resin or may be an unstretched thermoplastic resin (hereinafter sometimes referred to as "unstretched resin"). Examples of the stretching treatment include uniaxial stretching and biaxial stretching.

The thickness of the protective layer is preferably 3 μm or more, more preferably 5 μm or more. Further, the thickness of the protective layer is preferably 50 μm or less, more preferably 30 μm or less. In addition, the upper limit value and lower limit value mentioned above can be combined arbitrarily. As the thickness of the polarizing plate decreases, its rigidity decreases and it becomes more susceptible to the expansion and contraction stress of the polarizing layer. Therefore, in an optical laminate in which the polarizing plate has a protective layer with a small thickness, the ends of the optical laminate are susceptible to the expansion and contraction stress of the polarizing layer, and the hue of reflected light within the plane becomes uniform depending on environmental changes such as changes in humidity. There is a tendency for sexual performance to worsen. Therefore, in such an optical laminate, as described above, by setting the adhesive chipping distance L1 to 3 μm or more, the uniformity of the hue of reflected light within the plane deteriorates even when environmental changes occur. It is thought that this can be effectively suppressed.

The surface of the protective layer opposite to the polarizing layer may have a surface treatment layer, for example, a hard coat layer, an antireflection layer, an antisticking layer, an antiglare layer, a diffusion layer, etc. . The surface treatment layer may be another layer laminated on the protective layer, or may be formed by subjecting the surface of the protective layer to surface treatment.

(First retardation layer)
The first retardation layer is a liquid crystal layer containing a liquid crystal compound. The type of liquid crystal compound forming the liquid crystal layer is not particularly limited, and rod-like liquid crystal compounds, discotic liquid crystal compounds, and mixtures thereof can be used. The liquid crystal layer is formed by applying a liquid crystal layer forming composition containing a liquid crystal compound, a solvent, and various additives as necessary onto the alignment layer to form a coating film, and solidifying (curing) this coating film. , a liquid crystal layer which is a hardened layer of a liquid crystal compound can be formed. Alternatively, the liquid crystal layer may be formed by coating the composition for forming a liquid crystal layer on the first base layer to form a coating film, and stretching this coating film together with the first base layer. In addition to the liquid crystal compound and solvent described above, the composition for forming a liquid crystal layer may contain a polymerization initiator, a reactive additive, a leveling agent, a polymerization inhibitor, and the like. As the liquid crystal compound, solvent, polymerization initiator, reactive additive, leveling agent, polymerization inhibitor, etc., known ones can be used as appropriate.

The first base layer on which the liquid crystal layer is formed is preferably a film made of a resin material. As the resin material, for example, a resin material having excellent transparency, mechanical strength, thermal stability, stretchability, etc. is used. Specifically, polyolefin resins such as polyethylene and polypropylene; cyclic polyolefin resins such as norbornene polymers; polyester resins such as polyethylene terephthalate and polyethylene naphthalate; (meth)acrylic acid, poly(meth)methyl acrylate, etc. (meth)acrylic acid resins; cellulose ester resins such as triacetyl cellulose, diacetyl cellulose and cellulose acetate propionate; vinyl alcohol resins such as polyvinyl alcohol and polyvinyl acetate; polycarbonate resins; polystyrene resins; Arylate resins; polysulfone resins; polyethersulfone resins; polyamide resins; polyimide resins; polyetherketone resins; polyphenylene sulfide resins; polyphenylene oxide resins, and mixtures and copolymers thereof. Can be done. Among these resins, it is preferable to use any one of a cyclic polyolefin resin, a polyester resin, a cellulose ester resin, and a (meth)acrylic acid resin, or a mixture thereof.

The first base material layer may be a single layer or may have a multilayer structure of two or more layers. When having a multilayer structure, the types of resins forming each layer may be the same or different. The thickness of the first base layer is not particularly limited, but generally from the viewpoint of workability such as strength and handleability, it is preferably 1 to 300 μm, more preferably 10 to 200 μm, and 30 to 120 μm. It is even more preferable.

The above-mentioned alignment layer has an alignment regulating force that causes a liquid crystal compound such as a polymerizable liquid crystal compound contained in a liquid crystal layer formed thereon to align in a desired direction. Examples of the alignment layer include an alignment polymer layer formed of an alignment polymer, a photoalignment polymer layer formed of a photoalignment polymer, and a groove alignment layer having an uneven pattern or a plurality of grooves on the layer surface. Can be done. The thickness of the alignment layer is usually 10 to 500 nm, preferably 10 to 200 nm.

(Second retardation layer)
The second retardation layer may be a retardation film or a liquid crystal layer. The retardation film may be any material that exhibits optical anisotropy, such as polyvinyl alcohol, polycarbonate, polyester, polyarylate, polyimide, polyolefin, polycycloolefin, polystyrene, polysulfone, polyethersulfone, and polyvinylidene fluoride. /polymethyl methacrylate, acetyl cellulose, saponified ethylene-vinyl acetate copolymer, polyvinyl chloride, etc., and stretched films obtained by stretching the film by about 1.01 to 6 times.

When the second retardation layer is a liquid crystal layer, the same liquid crystal compound as that used to obtain the first retardation layer can be used, and it is formed by the same method as the formation method of the first retardation layer. be able to.

(Adhesive layer)
The adhesive layer is a layer formed using an adhesive. In this specification, an adhesive is an adhesive that exhibits adhesive properties by pasting itself onto an adherend such as an optical film or a liquid crystal layer, and is referred to as a so-called pressure-sensitive adhesive. As the adhesive, any conventionally known adhesive with excellent optical transparency can be used without any particular restriction. For example, an adhesive having a base polymer such as acrylic, urethane, silicone, or polyvinyl ether can be used. be able to. The thickness of the adhesive layer may be 3 μm or more, 5 μm or more, 35 μm or less, or 30 μm or less.

In addition to the above-mentioned ultraviolet absorber, the adhesive layer contains an antistatic agent using an ionic compound, a solvent, a crosslinking catalyst, a tackifying resin (tackifier), a plasticizer, a softener, a dye, a pigment, an inorganic filler, etc. It may contain additives.

(Adhesive layer)
The adhesive layer can be formed by an adhesive layer, an adhesive layer formed using an adhesive, or a combination thereof, and is usually one layer, but may be two or more layers. When the adhesive layer consists of two or more layers, each layer may be formed of the same material or different materials. The adhesive layer can be formed using the above-mentioned adhesive.

As the adhesive that can be used in the adhesive layer, conventionally known adhesives such as water-based adhesives and active energy ray-curable adhesives can be used without particular limitation. Examples of water-based adhesives include polyvinyl alcohol resin aqueous solutions, water-based two-component urethane emulsion adhesives, and the like. Active energy ray-curable adhesives are adhesives that are cured by irradiation with active energy rays such as ultraviolet rays, such as those containing a polymerizable compound and a photopolymerization initiator, those containing a photoreactive resin, Examples include those containing a binder resin and a photoreactive crosslinking agent. Examples of the polymerizable compound include photopolymerizable monomers such as photocurable epoxy monomers, photocurable acrylic monomers, and photocurable urethane monomers, and oligomers derived from these monomers. Examples of the photopolymerization initiator include those containing substances that generate active species such as neutral radicals, anion radicals, and cation radicals upon irradiation with active energy rays such as ultraviolet rays.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. "%" and "parts" in Examples and Comparative Examples are mass % and parts by mass unless otherwise specified.

[Preparation of polarizing plate]
A triacetyl cellulose film with a thickness of 20 μm was prepared as the first protective layer. As the second protective layer, a norbornene resin film having a thickness of 29 μm and having a hard coat layer formed on one surface was prepared. A PVA-based resin film in which iodine, a dichroic dye, was adsorbed and oriented was prepared as a polarizing layer. The thickness of the polarizing layer was 8 μm.

In addition, 3 parts by weight of carboxyl group-modified polyvinyl alcohol (trade name "KL-318" obtained from Kuraray Co., Ltd.) was dissolved in 100 parts by weight of water, and a polyamide epoxy additive, which is a water-soluble epoxy resin, was added to the aqueous solution. A water-based adhesive was prepared by adding 1.5 parts by weight of [trade name "Sumirezu Resin (registered trademark) 650 (30)" obtained from Taoka Chemical Industry Co., Ltd., an aqueous solution with a solid content concentration of 30% by weight]. .

The first protective layer was subjected to saponification treatment, and the surface of the second protective layer on the norbornene resin film side and both surfaces of the polarizing layer were subjected to corona treatment. A first protective layer is bonded to one surface of the polarizing layer via the water-based adhesive obtained above, and a second protective layer is bonded to the other surface of the polarizing layer via the same water-based adhesive as above. The side opposite to the hard coat layer (norbornene resin film side) was laminated and dried to produce a polarizing plate. The obtained polarizing plate was cut into a rectangular shape so that the absorption axis of the polarizing layer was at 45° with respect to the long side direction.

・溶媒（９５部）：シクロペンタノン [Preparation of first retardation layer]
(Preparation of composition for forming horizontal alignment layer)
A composition for forming a horizontal alignment layer was obtained by mixing the following components and stirring the resulting mixture at a temperature of 80° C. for 1 hour.
・Photoalignable material (5 parts) (weight average molecular weight: 30,000):

・Solvent (95 parts): cyclopentanone

・重合性液晶化合物Ｂ（１０部）：

・重合開始剤（６部）：
２－ジメチルアミノ－２－ベンジル－１－（４－モルホリノフェニル）ブタン－１－オン（イルガキュア３６９、ＢＡＳＦジャパン株式会社製） (Preparation of composition for forming horizontally aligned liquid crystal layer)
A composition for forming a horizontally aligned liquid crystal layer was prepared by mixing the following components, further adding N-methyl-2-pyrrolidone (NMP) so that the solid content concentration was 13%, and stirring at 80°C for 1 hour. I got something. The following polymerizable liquid crystal compound A was synthesized according to the method described in JP-A No. 2010-31223, and the following polymerizable liquid crystal compound B was synthesized according to the method described in JP-A No. 2009-173893.
・Polymerizable liquid crystal compound A (90 parts):

・Polymerizable liquid crystal compound B (10 parts):

・Polymerization initiator (6 parts):
2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (Irgacure 369, manufactured by BASF Japan Ltd.)

(Preparation of first retardation layer)
A cyclic olefin resin (COP) film (ZF-14-50, manufactured by Zeon Corporation) was subjected to corona treatment. The composition for forming a horizontal alignment layer obtained above was applied to the corona-treated surface of this COP film using a bar coater, and dried at 80° C. for 1 minute. This coating film was irradiated at an axis angle of 45° using a polarized UV irradiation device (“SPOT CURE SP-9”, manufactured by Ushio Inc.) so that the cumulative amount of light at a wavelength of 313 nm was 100 mJ/cm ² . A horizontal alignment layer was obtained by exposing to polarized UV light.

Subsequently, the composition for forming a horizontally aligned liquid crystal layer obtained above was applied to this horizontally aligned layer using a bar coater, and dried at 120° C. for 1 minute. The coating film is irradiated with ultraviolet rays (integrated light amount at a wavelength of 365 nm in a nitrogen atmosphere: 500 mJ/cm ² ) using a high-pressure mercury lamp ("Unicure VB-15201BY-A", manufactured by Ushio Inc.). A first retardation layer, which is a horizontally aligned liquid crystal layer, was thus formed. The first retardation layer was a quarter-wave plate exhibiting reverse wavelength dispersion.

[Preparation of second retardation layer]
(Preparation of composition for forming vertical alignment layer)
Sunever SE610 (manufactured by Nissan Chemical Industries, Ltd.) was prepared as a composition for forming a vertical alignment layer.

(Preparation of composition for forming vertically aligned liquid crystal layer)
The following components were mixed, and cyclopentanone was further added so that the solid content concentration was 13% to obtain a composition for forming a vertically aligned liquid crystal layer.
・Polymerizable liquid crystal compound C (100 parts):
Paliocolor (registered trademark) LC242 (manufactured by BASF)
・Leveling agent (0.1 part):
F-556 (manufactured by DIC)
・Polymerization initiator (3 parts):
Irgacure 369 (manufactured by Ciba Specialty Chemicals)

(Preparation of second retardation layer)
A cyclic olefin resin (COP) film (ZF-14-50, manufactured by Zeon Corporation) was subjected to corona treatment. The composition for forming a vertical alignment layer obtained above was applied to the corona-treated surface of this COP film using a bar coater, and dried at 80° C. for 1 minute to obtain a vertical alignment layer. Subsequently, the composition for forming a vertically aligned liquid crystal layer obtained above was applied to the vertically aligned layer using a bar coater, and dried at 90° C. for 120 seconds. This coating film is irradiated with ultraviolet rays (integrated light amount at a wavelength of 365 nm in a nitrogen atmosphere: 500 mJ/cm ² ) using a high-pressure mercury lamp ("Unicure VB-15201BY-A", manufactured by Ushio Inc.). As a result, a second retardation layer, which is a vertically aligned liquid crystal layer, was formed. The second retardation layer was a positive C plate that satisfied the relationship nx≈ny<nz.

[Production of retardation layer laminate]
Corona treatment was applied to the surface of the first retardation layer produced above on the opposite side to the COP film, and the surface of the second retardation layer produced above on the opposite side to the COP film. After the corona-treated surfaces (the first retardation layer surface and the second retardation layer surface) are bonded to each other via an ultraviolet curable adhesive, the ultraviolet curable adhesive is cured by irradiation with ultraviolet rays. A retardation layer laminate in which a first retardation layer and a second retardation layer were laminated via an adhesive layer was obtained. The obtained retardation layer laminate was cut into a rectangular shape so that the slow axis of the first retardation layer (1/4 wavelength plate) was parallel to the long side direction.

[Measurement of distance L1 of adhesive chipping part]
An acrylic adhesive layer with a thickness of 20 μm provided on a release film was laminated on the second retardation layer side of the optical laminate obtained in each example and each comparative example to obtain an optical laminate with an adhesive layer. . For this optical laminate with adhesive layer, check the side where the adhesive chipping part is formed, and at the position where the adhesive chipping part is formed, The profile of the cross section of the laminate was measured using a laser microscope. Based on the measured profile, the distance L1 between the innermost position at the end of the adhesive layer 61 and the outermost position at the end of the first retardation layer was measured.

[Weather resistance test]
An acrylic adhesive layer with a thickness of 20 μm was laminated on the second retardation layer side of the optical laminate obtained in each example and each comparative example, and this acrylic adhesive layer was bonded to a glass plate for evaluation. It was used as a sample. A weather resistance test was conducted by placing the obtained evaluation sample in a sunshine weather meter (weather resistance tester) for 100 hours. The evaluation sample after the weather resistance test was placed on a reflection plate (MIRO5 5011GP, manufactured by Alanod) with the glass plate facing down, and the reflected light was measured using a spectrophotometer (CM2600d, Konica Minolta, Inc.). The hue was measured. The measurement was carried out by wearing a mask with an opening diameter φ of 1.5 mm when light enters the integrating sphere from the evaluation sample, and the hue (a) of the reflected light at the center of the four edges of the evaluation sample was ^* b ^* ) and the hue (a ^* b ^* ) of the reflected light at the central portion of the evaluation sample (the intersection of the diagonal lines of the rectangle), and the average value of the difference was calculated as Δa ^* b ^* .
Δa ^* b ^* = (Δa ^*2 + Δb ^*2 ) ^1/2

In addition, after placing the evaluation sample after the weather resistance test on a reflection plate (manufactured by Alanod, MIRO5 5011GP), visually observe the reflected light from the optical laminate side to check the state of color unevenness of the optical laminate. Visibility was evaluated. The state of color unevenness was evaluated as A when it was weakly visible, and as B when it was strongly visible.

[Example 1]
FIGS. 3(a) and 3(b) are schematic diagrams for explaining a method for producing an adhesive layer in an example. As shown in FIG. 3(a), a release film-attached adhesive layer 60 having an adhesive layer 61 formed using an acrylic adhesive with a thickness of 20 μm on a release film 62 was prepared. The adhesive layer 61 contained an ultraviolet absorber. As shown in FIG. 3(a), the tip portion 65a is cut at an angle θ from the adhesive layer 61 side along a direction parallel to the stacking direction of the adhesive layer 60 with a release film (arrow direction in the figure). The adhesive layer 60 with a release film was cut into a rectangular shape by making a cut with the blade 65. A single-edged blade was used as the cutting blade 65. The cut surface of the rectangular release film-attached adhesive layer 60 after cutting was the surface in contact with the blade-formed surface of both surfaces of the single-edged cutting blade 65.

After laminating the adhesive layer 61 of the obtained rectangular adhesive layer 60 with a release film on the first protective layer side (triacetyl cellulose film side) of the polarizing plate produced above, the release film 62 was attached. Peeled off. After laminating the surface exposed by peeling off the COP film on the first retardation layer side of the retardation layer laminate produced above and the surface of the adhesive layer 61 exposed by peeling off the release film 62, The COP film on the second retardation layer side is peeled off, and the layer structure of the second protective layer/polarizing layer/first protective layer/adhesive layer 61/first retardation layer/adhesive layer/second retardation layer is An optical laminate (circularly polarizing plate) was obtained. In the production of an optical laminate, when laminating each layer, corona treatment is performed on the laminating surface, and when laminating, the long side and short side of each layer are aligned, and the absorption of the polarizing layer is The axial direction was set at 45° with respect to the slow axis direction of the first retardation layer.

The resulting optical laminate had adhesive defects formed around its entire circumference. The distance L1 was measured using the above-described procedure for the adhesive missing portion at any position on each side of the optical laminate, and the average value thereof was calculated. In addition, the obtained optical laminate was subjected to a weather resistance test, and the change in hue of reflected light was measured, and the visibility was evaluated to check the state of color unevenness. These results are shown in Table 1. In addition, from the measurement results of the distance L1 on each side, it was found that the distance L1 of the adhesive chipping portion was approximately the same as the value shown in Table 1 over the entire circumference of the optical laminate of this example.

[Example 2 and Comparative Example 1]
As a cutting blade used to cut the adhesive layer 60 with a release film (FIG. 3(a)), a rectangular cutting blade (single edge) with a tip portion 65a having a larger angle θ than that used in Example 1 is used. An optical laminate was obtained in the same manner as in Example 1, except that a pressure-sensitive adhesive layer 60 with a release film having a shape was obtained. The resulting optical laminate had adhesive defects formed around its entire circumference. The distance L1 was measured using the above-described procedure for the adhesive missing portion at any position on each side of the optical laminate, and the average value thereof was calculated. In addition, the obtained optical laminate was subjected to a weather resistance test, the change in hue of reflected light was measured, and the visibility was evaluated to check the state of color unevenness. These results are shown in Table 1. In addition, from the measurement results of the distance L1 on each side, it was found that the distance L1 of the adhesive missing portion was approximately the same as the value shown in Table 1 over the entire circumference of the optical laminate of this example.

5 adhesive chipping part, 11 optical laminate, 12 optical laminate, 21 first retardation layer, 22 second retardation layer, 31 adhesive layer, 35 adhesive layer, 40 polarizing plate, 41 polarizing layer, 42 first protection layer, 43 second protective layer, 60 adhesive layer with release film, 61 adhesive layer, 62 release film, 65 cutting blade, 65a cutting edge portion.

Claims (11)

An optical laminate comprising a polarizing layer, an adhesive layer, and a first retardation layer in this order,
Further, a second retardation layer is provided on the opposite side of the first retardation layer from the adhesive layer,
The second retardation layer is provided on the first retardation layer via an adhesive layer,
The first retardation layer and the second retardation layer are liquid crystal layers,
The optical laminate has an adhesive missing portion at an end in the surface direction,
In a cross section passing through a portion where the first retardation layer and the adhesive layer overlap in the lamination direction, the adhesive chipping portion is such that the position of the innermost end of the end of the adhesive layer is at the first retardation layer. An optical laminate formed so as to be located within a range of 0.2 μm or more and 10 μm or less from the outermost position of the end of the layer. The optical laminate has a rectangular shape or a rectangular shape having a notch on at least one side,
The optical laminate according to claim 1, wherein the adhesive missing portion is formed on at least one side of a rectangular shape. The square shape has a pair of long sides and a pair of short sides,
The absorption axis direction of the polarizing layer forms an angle of 45° ± 10° with respect to the long side,
The optical laminate according to claim 2, wherein the adhesive missing portion is formed on at least one of the pair of long sides and at least one of the pair of short sides. The square shape has a pair of long sides and a pair of short sides,
The absorption axis direction of the polarizing layer makes an angle of 0° ± 10° with respect to the long side,
The optical laminate according to claim 2, wherein the adhesive missing portion is formed on at least one of the pair of short sides. The square shape has a pair of long sides and a pair of short sides,
The absorption axis direction of the polarizing layer makes an angle of 0° ± 10° with respect to the short side,
The optical laminate according to claim 2, wherein the adhesive missing portion is formed on at least one of the pair of long sides. Any one of claims 1 to 5, wherein the adhesive layer in the adhesive chipping portion has an end position on the first retardation layer side that is outward in the plane direction from an end position on the surface of the polarizing layer. The optical laminate according to item 1. The optical laminate according to any one of claims 1 to 6, which has a protective layer on one or both sides of the polarizing layer. In a cross section passing through a portion where the first retardation layer and the adhesive layer overlap in the lamination direction, the adhesive chipping portion is such that the position of the innermost end of the end of the adhesive layer is at the first retardation layer. The optical laminate according to any one of claims 1 to 7, which is formed so as to be located within a range of 8 μm or less from the outermost position of the end of the layer . The first retardation layer is a 1/2 wavelength plate, and the second retardation layer is a 1/4 wavelength plate,
The first retardation layer is a quarter-wave plate with reverse wavelength dispersion, and the second retardation layer is a positive C plate, or
The optical laminate according to claim 1, wherein the first retardation layer is a positive C plate, and the second retardation layer is a quarter-wave plate with reverse wavelength dispersion . The optical laminate according to any one of claims 1 to 9, wherein the adhesive layer contains an ultraviolet absorber. The optical laminate according to any one of claims 1 to 10, which is a circularly polarizing plate.

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