JP2022169027A - Method of manufacturing polarizing plate with retardation layer - Google Patents

Abstract

To allow for manufacturing a polarizing plate with a retardation layer with good yield.SOLUTION: A method of manufacturing a polarizing plate with a retardation layer according to an embodiment of the present invention comprises, in the described order: preparing a laminate comprising a release film, an adhesive layer, a first retardation layer, and a base material located adjacent to the first retardation layer, arranged in the described order; peeling the release film off from the adhesive layer; and pasting the laminae onto a polarizing plate.SELECTED DRAWING: Figure 1A

Description

TECHNICAL FIELD The present invention relates to a method for producing a polarizing plate with a retardation layer.

Image display devices typified by liquid crystal display devices and electroluminescence (EL) display devices (eg, organic EL display devices and inorganic EL display devices) are rapidly spreading. A polarizing plate and a retardation plate are typically used in an image display panel mounted in an image display device. Practically, a polarizing plate with a retardation layer, in which a polarizing plate and a retardation plate are integrated, is widely used (for example, Patent Document 1). Here, it is desired to laminate the polarizing plate and the retardation layer satisfactorily to improve the production efficiency of the polarizing plate with the retardation layer.

Japanese Patent No. 3325560

In view of the above, a main object of the present invention is to produce a polarizing plate with a retardation layer with good yield.

An embodiment of the present invention provides a method for manufacturing a polarizing plate with a retardation layer. This manufacturing method comprises preparing a laminate containing, in this order, a release film, an adhesive layer, a first retardation layer, and a base material arranged adjacent to the first retardation layer, from the adhesive layer Peeling off the release film and bonding the laminate to a polarizing plate are included in this order.

In one embodiment, the release film is peeled off in a direction of 120° to 180° with respect to the surface of the pressure-sensitive adhesive layer.
In one embodiment, the manufacturing method includes peeling the substrate from the first retardation layer after bonding the laminate to the polarizing plate.
In one embodiment, the peel strength of the release film from the pressure-sensitive adhesive layer is smaller than the peel strength of the first retardation layer from the substrate.
In one embodiment, the ratio (F1/F2) of the release force F1 of the release film to the pressure-sensitive adhesive layer to the release force F2 of the first retardation layer to the substrate (F1/F2) is a peel speed of 1000 mm / sec and peel It is less than 1 when the angle is 180° and is greater than or equal to 1 when the peel speed is 1000 mm/sec and the peel angle is 90°.
In one embodiment, the manufacturing method includes cutting an end portion of the laminate before bonding the laminate to the polarizing plate, and the cutting cuts the end face of the pressure-sensitive adhesive layer and the The end face of the first retardation layer is flush with the end face. After the cutting, the release film may be peeled off from the pressure-sensitive adhesive layer.
In one embodiment, an identification code is formed on the edge of the polarizing plate.
In one embodiment, the first retardation layer is an alignment fixed layer of a liquid crystal compound.
In one embodiment, the thickness of the first retardation layer is 5 μm or less.
In one embodiment, the pressure-sensitive adhesive layer has a thickness of 10 µm or less.
In one embodiment, the pressure-sensitive adhesive layer has a thickness of 6 μm or more.
In one embodiment, the manufacturing method further includes laminating a second retardation layer after bonding the laminate to the polarizing plate.

According to the embodiment of the present invention, a polarizing plate with a retardation layer can be produced with high yield.

1 is a diagram showing manufacturing process 1 of a polarizing plate with a retardation layer according to one embodiment of the present invention; FIG. It is a figure which shows the process 2 following the said process 1. FIG. It is a figure which shows the process 3 following the said process 2. FIG. It is a figure which shows the process 4 following the said process 3. FIG. It is a figure which shows the process 5 following the said process 4. FIG. It is a figure which shows an example of the state which peels a peeling film from a laminated body. It is a figure which shows the modification of a laminated body (process 1).

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. In addition, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the embodiment, but this is only an example, and the interpretation of the present invention is not limited. It is not limited.

(Definition of terms and symbols)
Definitions of terms and symbols used herein are as follows.
(1) refractive index (nx, ny, nz)
"nx" is the refractive index in the direction in which the in-plane refractive index is maximum (i.e., slow axis direction), and "ny" is the in-plane direction orthogonal to the slow axis (i.e., fast axis direction) and "nz" is the refractive index in the thickness direction.
(2) In-plane retardation (Re)
“Re(λ)” is an in-plane retardation measured at 23° C. with light having a wavelength of λ nm. For example, "Re(550)" is the in-plane retardation measured with light having a wavelength of 550 nm at 23°C. Re(λ) is obtained by the formula: Re(λ)=(nx−ny)×d, where d (nm) is the thickness of the layer (film).
(3) Thickness direction retardation (Rth)
“Rth(λ)” is the retardation in the thickness direction measured at 23° C. with light having a wavelength of λ nm. For example, “Rth(550)” is the retardation in the thickness direction measured at 23° C. with light having a wavelength of 550 nm. Rth(λ) is determined by the formula: Rth(λ)=(nx−nz)×d, where d (nm) is the thickness of the layer (film).
(4) Nz Coefficient The Nz coefficient is obtained by Nz=Rth/Re.
(5) Angle When referring to an angle in this specification, the angle includes both clockwise and counterclockwise directions with respect to a reference direction. Thus, for example, "45°" means ±45°.

In the method for producing a polarizing plate with a retardation layer according to one embodiment of the present invention, a release film, an adhesive layer, a first retardation layer, and a base material arranged adjacent to the first retardation layer are placed in this order. , peeling the release film from the pressure-sensitive adhesive layer, and laminating the laminate to the polarizing plate in this order.

1A to 1E are diagrams showing steps of a method for manufacturing a polarizing plate with a retardation layer according to one embodiment of the present invention. In step 1 shown in FIG. 1A, the pressure-sensitive adhesive layer 30 is formed above the first retardation layer 21 formed on the substrate 11, and the release film 40 is placed on the pressure-sensitive adhesive layer 30 to form the laminate 100. obtain. The upper surface of the first retardation layer 21 may be protected with a surface protection film before forming the adhesive layer 30 (not shown). The release film 40 is detachably attached to the adhesive layer 30 and can protect the adhesive layer 30 . The laminate 100 is elongated and can be wound into a roll, for example. Here, the term "elongated" refers to an elongated shape whose length is sufficiently longer than its width, for example, an elongated shape whose length is 10 times or more, preferably 20 times or more, its width.

In step 1 , the end face 21 a of the first retardation layer 21 is located inside the end face 11 a of the base material 11 and outside the end face 30 a of the adhesive layer 30 . Further, the end face 30a of the pressure-sensitive adhesive layer 30 is positioned inside the end face 40a of the release film 40 .

In step 2, the widthwise end of the laminate is cut (slit) along the dashed line in FIG. 1A, and FIG. 1B shows the state after the cutting is completed. By cutting, the end face 30a of the adhesive layer 30 and the end face 21a of the first retardation layer 21 are made flush with each other. By removing the end portion 21b where the upper surface of the first retardation layer 21 is not covered with the adhesive layer 30, contamination such as adhesion of foreign matter to the upper surface of the first retardation layer 21 can be prevented in the manufacturing process. . In addition, contamination of the manufacturing machine (specifically, the inside of the manufacturing machine) can be suppressed. By producing a laminate as shown in FIG. 1A, such cutting can be performed before lamination of the polarizing plate and the retardation layer, which will be described later, which can contribute to an improvement in yield.

In step 3 shown in FIG. 1C , the laminate 100 from which the release film 40 has been removed is attached to the polarizing plate 70 . Lamination of the polarizing plate 70 and the laminate 100 (first retardation layer 21) is performed, for example, while conveying these by rolls (so-called roll-to-roll).

The polarizing plate 70 includes a polarizer 69, a first protective layer 71 arranged on the viewing side of the polarizer 69 (the side where the first retardation layer 21 is not arranged), and the other side of the polarizer 69 (the polarizer 69 and and a second protective layer 72 disposed between the first retardation layer 21). In the illustrated example, the upper surface 70 a of the polarizing plate 70 is protected by the surface protective film 60 . The surface protection film 60 includes a base material and an adhesive layer formed on one side of the base material (not shown), and is detachably attached to the polarizing plate 70 . Unlike the illustrated example, the second protective layer 72 of the polarizing plate 70 may be omitted. Moreover, although not shown, the lower surface 70b of the polarizing plate 70 may be protected with a surface protection film before the laminate 100 is attached.

FIG. 2 is a diagram showing an example of a state in which a release film is peeled off from a laminate. In the illustrated example, the peeling film 40 is peeled off while the laminate 100 is transported in rolls in the length direction L. As shown in FIG. For example, a tape (not shown) is attached to the surface of the release film 40, and the release film 40 is peeled off from the laminate 100 (adhesive layer 30) by pulling the tape. The peeling direction of the peeling film 40 is the direction forming an angle θ with respect to the surface 30b (conveying direction) of the adhesive layer 30 . In the illustrated example, a folding member M is used to fold the release film 40 in the release direction.

The angle θ (peeling angle) is preferably 120° or more. Specifically, it is preferably 120° to 180°. The angle θ (peeling angle) is more preferably 140° or more, still more preferably 160° or more. By peeling the release film 40 at such a peeling angle, the peeling force when peeling the release film 40 from the pressure-sensitive adhesive layer 30 can be reduced, and workability at the time of peeling can be improved. Specifically, when the release film 40 is released by making the release force (F1) of the release film 40 relative to the adhesive layer 30 smaller than the release force (F2) of the first retardation layer 21 relative to the substrate 11, In addition, it is possible to prevent peeling between the first retardation layer 21 and the substrate 11 (prevent peeling defects), which can contribute to an improvement in yield. The ratio of F1 to F2 (F1/F2) is preferably less than 1, more preferably 0.8 or less, even more preferably 0.6 or less.

The peeling force (F1) of the release film 40 to the adhesive layer 30 is preferably 0.1 N/25 mm or less, more preferably 0.08 N/25 mm or less, and still more preferably 0.06 N/25 mm or less. . Such peel force can be better achieved by the peel angle. Note that F1 can also be adjusted by appropriately selecting, for example, the configuration of the pressure-sensitive adhesive layer 30, the type of the release film 40, and the like.

The peel force (F2) of the first retardation layer 21 with respect to the base material 11 may exceed, for example, 0.06 N/25 mm, may be 1 N/25 mm or less, or may be 0.5 N/25 mm or less.

In one embodiment, the ratio of F1 to F2 (F1/F2) is less than 1 at a peel speed of 1000 mm/sec and a peel angle of 180°, and at a peel speed of 1000 mm/sec and a peel angle of 90°. is greater than or equal to 1.

As described above, according to the above process, the end portion 21b of the first retardation layer 21 can be removed before the polarizing plate 70 and the first retardation layer 21 are laminated, and the polarizing plate 70 can be cut. It can contribute to the improvement of the yield. Further, as shown in FIG. 1C, the width direction end of the polarizing plate 70 (practically, the surface protective film 60 attached to the upper surface of the polarizing plate 70) has, for example, a detected defect (for example, an appearance defect) can be formed (printed), but the removal of the end portion 21b of the first retardation layer 21 does not remove the identification code K either.

In step 4 shown in FIG. 1D, after the polarizing plate 70 and the first retardation layer 21 are laminated, the substrate 11 is peeled off from the first retardation layer 21, and the first retardation layer 21 is formed on the substrate 12. The laminated second retardation layer 22 is laminated via an adhesive layer (not shown). According to such a process, defects (for example, defects in appearance) can be easily detected for each of the retardation layers 21 and 22, which can contribute to an improvement in yield. In the illustrated example, the end surface 22a of the second retardation layer 22 is located inside the end surface 21a of the first retardation layer 21, but the positional relationship thereof is not particularly limited. Specifically, the width of the second retardation layer 22 may be smaller than, larger than, or the same as the width of the first retardation layer 21 . Although the second retardation layer 22 is provided in the illustrated example, it may not be provided. In this specification, the layer including at least the first retardation layer 21 may be simply referred to as the retardation layer 20 in some cases. Specifically, the retardation layer 20 may have a laminated structure of two or more layers, or may be a single layer. In the illustrated example, the retardation layer 20 has a laminated structure including a first retardation layer 21 and a second retardation layer 22 .

In step 5 shown in FIG. 1E, the substrate 12 is peeled off from the second retardation layer 22, the adhesive layer 80 is formed, and the release film 90 is attached to the second retardation layer 22 via the adhesive layer 80. to obtain a polarizing plate 110 with a retardation layer. Practically, the pressure-sensitive adhesive layer 80 enables the retardation layer-attached polarizing plate 110 to be attached to the image display panel main body. The release film 90 can function as a separator that is temporarily attached until the polarizing plate 110 with the retardation layer is used. By temporarily attaching the release film, for example, the pressure-sensitive adhesive layer can be protected and roll formation of the retardation layer-attached polarizing plate becomes possible.

Although not shown, the laminate 100 may include other members. FIG. 3 is a diagram showing a modification of the laminate (step 1). In the modification of step 1 shown in FIG. 3, a retardation layer protective material 50 is formed on the first retardation layer 21 formed on the substrate 11, and the adhesive layer 30 is formed on the protective material 50. , the release film 40 is placed on the adhesive layer 30 to obtain the laminate 100 . Before forming the protective material 50, the upper surface of the first retardation layer 21 may be protected with a surface protective film (not shown). Also, the upper surface of the protective material 50 may be protected with a surface protective film (not shown) before the adhesive layer 30 is formed.

Each of the above members can be laminated via any appropriate adhesive layer (part of which is not shown). Specific examples of the adhesive layer include an adhesive layer and an adhesive layer. For example, the first retardation layer 21 and the second retardation layer 22 are attached via an adhesive layer. Specifically, they are bonded using an active energy ray-curable adhesive. The thickness of the active energy ray-curable adhesive after curing (thickness of the adhesive layer) is, for example, 0.2 μm to 3.0 μm, preferably 0.4 μm to 2.0 μm, more preferably 0.6 μm. ˜1.5 μm.

1. Polarizing Plate The polarizing plate includes a polarizer and a protective layer. The thickness of the polarizing plate is preferably 20 μm or more, more preferably 25 μm or more, depending on the number of protective layers included. On the other hand, the thickness of the polarizing plate is preferably 75 μm or less. The thickness of the polarizing plate may be 70 μm or less, 60 μm or less, 50 μm or less, or 40 μm or less. The thickness of the polarizing plate does not include the thickness of an adhesive layer (for example, an adhesive layer) when laminating the polarizer and the protective layer.

The polarizer is typically a resin film containing a dichroic substance (eg, iodine). Examples of resin films include hydrophilic polymer films such as polyvinyl alcohol (PVA) films, partially formalized PVA films, and partially saponified ethylene/vinyl acetate copolymer films.

The thickness of the polarizer is preferably 15 μm or less, more preferably 12 μm or less, even more preferably 10 μm or less, and particularly preferably 8 μm or less. On the other hand, the thickness of the polarizer is preferably 1 μm or more.

The polarizer preferably exhibits absorption dichroism at any wavelength of 380 nm to 780 nm. The single transmittance of the polarizer is, for example, 41.5% to 46.0%, preferably 42.0% to 46.0%, more preferably 44.5% to 46.0%. The degree of polarization of the polarizer is preferably 97.0% or higher, more preferably 99.0% or higher, still more preferably 99.9% or higher.

The protective layer may be formed of any appropriate film that can be used as a protective layer for polarizers. Specific examples of the material that is the main component of the film include cellulose resins such as triacetyl cellulose (TAC), polyesters, polyvinyl alcohols, polycarbonates, polyamides, polyimides, polyethersulfones, polysulfones, Examples include resins such as polystyrene, cycloolefins such as polynorbornene, polyolefins, (meth)acrylic, and acetate.

The polarizing plate with a retardation layer obtained by the embodiment of the present invention is typically arranged on the viewer side of the image display device, and the first protective layer 71 is arranged on the viewer side. Therefore, the first protective layer 71 may be subjected to surface treatment such as hard coat (HC) treatment, anti-reflection treatment, anti-sticking treatment, and anti-glare treatment, if necessary.

The thickness of the protective layer is preferably 5 μm to 80 μm, more preferably 10 μm to 40 μm, still more preferably 15 μm to 35 μm. In addition, when the said surface treatment is performed, the thickness of the 1st protective layer 71 is thickness including the thickness of a surface treatment layer.

The second protective layer 22 disposed between the polarizer 69 and the first retardation layer 21 is preferably optically isotropic in one embodiment. As used herein, “optically isotropic” means that the in-plane retardation Re (550) is 0 nm to 10 nm and the thickness direction retardation Rth (550) is −10 nm to +10 nm. Say. The thickness of the second protective layer 22 is preferably 5 μm to 80 μm, more preferably 10 μm to 40 μm, still more preferably 10 μm to 30 μm.

A polarizing plate can be made by any suitable method. Specifically, the polarizing plate may include a polarizer produced from a single-layer resin film, or may include a polarizer obtained using a laminate of two or more layers.

The method of producing a polarizer from the single-layer resin film typically includes dyeing the resin film with a dichroic substance such as iodine or a dichroic dye and stretching the film. As the resin film, for example, hydrophilic polymer films such as polyvinyl alcohol (PVA) films, partially formalized PVA films, and partially saponified ethylene/vinyl acetate copolymer films are used. The method may further include an insolubilization treatment, a swelling treatment, a cross-linking treatment, and the like. A polarizing plate can be obtained by laminating a protective layer on at least one of the obtained polarizers. Since such a manufacturing method is well known and commonly used in the industry, detailed description thereof will be omitted.

A polarizer obtained using the laminate can be produced, for example, using a laminate of a resin substrate and a resin film or resin layer (typically, a PVA-based resin layer). Specifically, a PVA-based resin solution is applied to a resin base material, dried to form a PVA-based resin layer on the resin base material, and a laminate of the resin base material and the PVA-based resin layer is obtained; stretching and dyeing the laminate to make the PVA-based resin layer a polarizer; In this embodiment, preferably, a PVA-based resin layer containing a halide and a PVA-based resin is formed on one side of the resin substrate. Stretching typically includes immersing the laminate in an aqueous boric acid solution for stretching. Furthermore, stretching may further include stretching the laminate in air at a high temperature (eg, 95° C. or higher) before stretching in an aqueous boric acid solution, if necessary. In addition, in the present embodiment, the laminate is preferably subjected to drying shrinkage treatment in which the laminate is heated while being conveyed in the longitudinal direction to shrink the laminate by 2% or more in the width direction. Typically, the manufacturing method of the present embodiment includes subjecting the laminate to an in-air auxiliary stretching treatment, a dyeing treatment, an underwater stretching treatment, and a drying shrinkage treatment in this order. By introducing auxiliary stretching, it is possible to improve the crystallinity of PVA and achieve high optical properties even when PVA is applied onto a thermoplastic resin. At the same time, by increasing the orientation of PVA in advance, it is possible to prevent problems such as deterioration of orientation and dissolution of PVA when immersed in water in the subsequent dyeing process or stretching process, resulting in high optical properties. can be achieved. Furthermore, when the PVA-based resin layer is immersed in a liquid, compared with the case where the PVA-based resin layer does not contain a halide, the disturbance of the orientation of the PVA molecules and the deterioration of the orientation can be suppressed, and high optical properties can be obtained. achievable. Furthermore, high optical properties can be achieved by shrinking the laminate in the width direction by drying shrinkage treatment. The obtained resin substrate/polarizer laminate may be used as it is (that is, the resin substrate may be used as a protective layer for the polarizer), or the resin substrate may be peeled off from the resin substrate/polarizer laminate. Any appropriate protective layer may be laminated according to the purpose on the peeled surface or on the surface opposite to the peeled surface. Details of the method for manufacturing such a polarizer are described in, for example, Japanese Patent Application Laid-Open No. 2012-73580 and Japanese Patent No. 6470455. These publications are incorporated herein by reference in their entireties.

2. Retardation layer The thickness of the retardation layer 20 is, for example, 1 μm or more and 10 μm or less, preferably 8 μm or less, more preferably 7 μm or less, depending on its configuration (whether it has a single layer or a laminated structure). is. The thickness of the first retardation layer 21 is preferably 5 μm or less. When the retardation layer has a laminated structure, the "thickness of the retardation layer" means the total thickness of each retardation layer. Specifically, the "thickness of the retardation layer" does not include the thickness of the adhesive layer.

As the retardation layer, an alignment fixed layer of a liquid crystal compound (liquid crystal alignment fixed layer) is preferably used. By using a liquid crystal compound, for example, the difference between nx and ny in the resulting retardation layer can be significantly increased compared to a non-liquid crystal material. thickness can be significantly reduced. Therefore, it is possible to realize a remarkable thinning of the polarizing plate with the retardation layer. As used herein, the term "fixed alignment layer" refers to a layer in which a liquid crystal compound is aligned in a predetermined direction and the alignment state is fixed. In addition, the "alignment fixed layer" is a concept including an alignment cured layer obtained by curing a liquid crystal monomer as described later. In the retardation layer, rod-shaped liquid crystal compounds are typically aligned in the slow axis direction of the retardation layer (homogeneous alignment).

The liquid crystal alignment fixed layer is formed by subjecting the surface of the substrate (substrates 11 and 12) to alignment treatment, coating the surface with a coating liquid containing a liquid crystal compound, and applying the liquid crystal compound in the direction corresponding to the alignment treatment. , and fixing the orientation state. Polymer films are typically used as the substrates (substrates 11 and 12). Materials for the polymer film include, for example, cellulose-based polymers and cycloolefin-based polymers such as polynorbornene. The thickness of the substrate is, for example, 5 μm to 100 μm.

Any appropriate alignment treatment may be adopted as the alignment treatment. Specific examples include mechanical orientation treatment, physical orientation treatment, and chemical orientation treatment. Specific examples of mechanical orientation treatment include rubbing treatment and stretching treatment. Specific examples of physical orientation treatment include magnetic orientation treatment and electric field orientation treatment. Specific examples of chemical alignment treatment include oblique vapor deposition and photo-alignment treatment. Arbitrary appropriate conditions can be adopted as the processing conditions for various alignment treatments depending on the purpose.

Alignment of the liquid crystal compound is performed by treatment at a temperature at which a liquid crystal phase is exhibited depending on the type of liquid crystal compound. By performing such a temperature treatment, the liquid crystal compound assumes a liquid crystal state, and the liquid crystal compound is aligned in accordance with the orientation treatment direction of the surface of the base material.

In one embodiment, the alignment state is fixed by cooling the liquid crystal compound aligned as described above. When the liquid crystal compound is a polymerizable monomer or a crosslinkable monomer, the orientation state is fixed by subjecting the liquid crystal compound oriented as described above to a polymerization treatment or a crosslinking treatment.

Specific examples of the liquid crystal compound and details of the method for forming the alignment fixed layer are described in JP-A-2006-163343. The description of the publication is incorporated herein by reference.

As described above, the retardation layer may be a single layer or may have a laminated structure of two or more layers.

Unlike the illustrated example, in one embodiment where the retardation layer is a single layer, the retardation layer can function as a λ/4 plate. Specifically, Re(550) of the retardation layer is preferably 100 nm to 180 nm, more preferably 110 nm to 170 nm, still more preferably 110 nm to 160 nm. The thickness of the retardation layer can be adjusted so as to obtain the desired in-plane retardation of the λ/4 plate. When the retardation layer is the liquid crystal alignment fixing layer described above, its thickness is, for example, 1.0 μm to 2.5 μm. In the present embodiment, the angle formed by the slow axis of the retardation layer and the absorption axis of the polarizer is preferably 40 ° to 50 °, more preferably 42 ° to 48 °, still more preferably 44 ° to 46°. Moreover, the retardation layer preferably exhibits reverse dispersion wavelength characteristics in which the retardation value increases according to the wavelength of the measurement light.

In another embodiment where the retardation layer is a single layer, the retardation layer can function as a λ/2 plate. Specifically, Re(550) of the retardation layer is preferably 200 nm to 300 nm, more preferably 230 nm to 290 nm, still more preferably 230 nm to 280 nm. The thickness of the retardation layer can be adjusted so as to obtain the desired in-plane retardation of the λ/2 plate. When the retardation layer is the liquid crystal alignment fixed layer described above, its thickness is, for example, 2.0 μm to 4.0 μm. In the present embodiment, the angle formed by the slow axis of the retardation layer and the absorption axis of the polarizer is preferably 10 ° to 20 °, more preferably 12 ° to 18 °, still more preferably 12 ° to 16°.

As illustrated, in one embodiment in which the retardation layer 20 has a laminated structure, the retardation layer 20 includes a first retardation layer (H layer) 21 and a second retardation layer in order from the polarizing plate 70 side. It has a two-layer laminated structure in which a layer (Q layer) 22 is arranged. The H layer can typically function as a λ/2 plate and the Q layer can typically function as a λ/4 plate. Specifically, Re(550) of the H layer is preferably 200 nm to 300 nm, more preferably 220 nm to 290 nm, still more preferably 230 nm to 280 nm; Re(550) of the Q layer is preferably It is 100 nm to 180 nm, more preferably 110 nm to 170 nm, even more preferably 110 nm to 150 nm. The thickness of the H layer can be adjusted to obtain the desired in-plane retardation of the λ/2 plate. When the H layer is the liquid crystal alignment fixing layer described above, its thickness is, for example, 2.0 μm to 4.0 μm. The thickness of the Q layer can be adjusted to obtain the desired in-plane retardation of the λ/4 plate. When the Q layer is the liquid crystal alignment fixing layer described above, its thickness is, for example, 1.0 μm to 2.5 μm. In the present embodiment, the angle between the slow axis of the H layer and the absorption axis of the polarizer is preferably 10° to 20°, more preferably 12° to 18°, still more preferably 12°. ~16°; the angle formed by the slow axis of the Q layer and the absorption axis of the polarizer is preferably 70° to 80°, more preferably 72° to 78°, still more preferably 72° ~76°. The arrangement order of the H layer and the Q layer may be reversed, and the angle between the slow axis of the H layer and the absorption axis of the polarizer and the angle between the slow axis of the Q layer and the absorption axis of the polarizer The angles may be reversed. In addition, each layer (for example, the H layer and the Q layer) may exhibit an inverse dispersion wavelength characteristic in which the retardation value increases according to the wavelength of the measurement light, and the retardation value increases according to the wavelength of the measurement light. It may exhibit a small positive wavelength dispersion characteristic, or may exhibit a flat wavelength dispersion characteristic in which the retardation value hardly changes even with the wavelength of the measurement light.

The retardation layer (at least one layer if it has a laminated structure) typically exhibits a relationship of nx>ny=nz in refractive index characteristics. Note that "ny=nz" includes not only the case where ny and nz are completely equal but also the case where they are substantially equal. Therefore, ny>nz or ny<nz may be satisfied within a range that does not impair the effects of the present invention. The Nz coefficient of the retardation layer is preferably 0.9 to 1.5, more preferably 0.9 to 1.3.

As described above, the retardation layer is preferably a liquid crystal alignment fixed layer. Examples of the liquid crystal compound include a liquid crystal compound having a nematic liquid crystal phase (nematic liquid crystal). As such a liquid crystal compound, for example, a liquid crystal polymer or a liquid crystal monomer can be used. Either lyotropic or thermotropic mechanism may be used to develop the liquid crystallinity of the liquid crystal compound. The liquid crystal polymer and liquid crystal monomer may be used alone or in combination.

When the liquid crystal compound is a liquid crystal monomer, the liquid crystal monomer is preferably a polymerizable monomer and a crosslinkable monomer. This is because the alignment state of the liquid crystal monomer can be fixed by polymerizing or cross-linking (that is, curing) the liquid crystal monomer. After aligning the liquid crystal monomers, for example, the alignment state can be fixed by polymerizing or cross-linking the liquid crystal monomers. Here, a polymer is formed by polymerization and a three-dimensional network structure is formed by cross-linking, but these are non-liquid crystalline. Therefore, the formed retardation layer does not undergo a transition to a liquid crystal phase, a glass phase, or a crystal phase due to a change in temperature, which is peculiar to liquid crystalline compounds. As a result, the retardation layer becomes a highly stable retardation layer that is not affected by temperature changes.

The temperature range in which the liquid crystal monomer exhibits liquid crystallinity varies depending on the type. Specifically, the temperature range is preferably 40°C to 120°C, more preferably 50°C to 100°C, and most preferably 60°C to 90°C.

Any appropriate liquid crystal monomer can be employed as the liquid crystal monomer. For example, polymerizable mesogenic compounds described in JP-T-2002-533742 (WO00/37585), EP358208 (US5211877), EP66137 (US4388453), WO93/22397, EP0261712, DE19504224, DE4408171, and GB2280445 can be used. Specific examples of such polymerizable mesogenic compounds include LC242 (trade name) available from BASF, E7 (trade name) available from Merck, and LC-Sillicon-CC3767 (trade name) available from Wacker-Chem. A nematic liquid crystal monomer is preferable as the liquid crystal monomer.

In another embodiment, the retardation layer 20 includes a first retardation layer 21 that can function as a λ/4 plate and a second retardation layer 22 (so-called It has a laminated structure with a positive C plate). The details of the λ/4 plate are as described above. In the present embodiment, the angle between the slow axis of the first retardation layer and the absorption axis of the polarizer is preferably 40° to 50°, more preferably 42° to 48°, still more preferably is 44° to 46°. Moreover, the first retardation layer preferably exhibits reverse dispersion wavelength characteristics in which the retardation value increases according to the wavelength of the measurement light.

The thickness direction retardation Rth (550) of the positive C plate is preferably −50 nm to −300 nm, more preferably −70 nm to −250 nm, still more preferably −90 nm to −200 nm, and particularly preferably is -100 nm to -180 nm. Here, "nx=ny" includes not only the case where nx and ny are strictly equal but also the case where nx and ny are substantially equal. The in-plane retardation Re(550) of the positive C plate is, for example, less than 10 nm.

The second retardation layer having refractive index properties of nz>nx=ny can be made of any suitable material, but preferably consists of a film containing a liquid crystal material fixed in homeotropic alignment. A liquid crystal material (liquid crystal compound) capable of homeotropic alignment may be a liquid crystal monomer or a liquid crystal polymer. Specific examples of the liquid crystal compound and the method for forming the retardation layer include the liquid crystal compound and the method for forming the retardation layer described in [0020] to [0028] of JP-A-2002-333642. In this case, the thickness of the second retardation layer is preferably 0.5 μm to 5 μm.

3. Surface Protection Film The substrate of the surface protection film can be made of any appropriate material. Specific examples of forming materials include polyester-based polymers such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); cellulose-based polymers such as diacetyl cellulose and triacetyl cellulose; polycarbonate-based polymers; (meth)acrylic polymers such as methyl methacrylate; cycloolefin polymers such as polynorbornene; These may be used alone or in combination of two or more.

The thickness of the substrate of the surface protection film is preferably 15 μm to 50 μm, more preferably 25 μm to 40 μm.

Any appropriate configuration can be adopted as the pressure-sensitive adhesive layer of the surface protection film. Specific examples include acrylic adhesives, rubber adhesives, silicone adhesives, polyester adhesives, urethane adhesives, epoxy adhesives, and polyether adhesives. By adjusting the type, number, combination and compounding ratio of the monomers forming the base resin of the adhesive, as well as the compounding amount of the cross-linking agent, the reaction temperature, the reaction time, etc., an adhesive having desired properties according to the purpose. can be prepared. The base resin of the adhesive may be used alone or in combination of two or more. The base resin is preferably an acrylic resin (specifically, the pressure-sensitive adhesive layer is preferably composed of an acrylic pressure-sensitive adhesive). The storage modulus of the pressure-sensitive adhesive layer at 25° C. is, for example, 1.0×10 ⁵ Pa to 1.0×10 ⁷ Pa. The thickness of the adhesive layer is, for example, 5 μm to 15 μm.

The thickness of the surface protective film is preferably 30 μm to 60 μm, more preferably 30 μm to 50 μm.

4. Adhesive Layer The thickness of the adhesive layer 30 used when laminating the first retardation layer 21 on the polarizing plate 70 is preferably 10 μm or less, more preferably 8 μm or less. On the other hand, the thickness of the adhesive layer 30 is preferably 2 μm or more, more preferably 4 μm or more, and even more preferably 6 μm or more. The thickness of the adhesive layer 80 is, for example, 10 μm to 40 μm. Details of the adhesive constituting the adhesive layers 30 and 80 are the same as those of the adhesive layer included in the surface protection film.

5. Release Film The release film may be composed of any suitable plastic film. Specific examples of plastic films include polyethylene terephthalate (PET) films, polyethylene films, and polypropylene films. As noted above, the release film can function as a separator. Specifically, a plastic film whose surface is coated with a release agent is preferably used as the release film. Specific examples of release agents include silicone-based release agents, fluorine-based release agents, and long-chain alkyl acrylate-based release agents.

The thickness of the release film is preferably 20 μm to 80 μm, more preferably 35 μm to 55 μm.

6. Protective Material As described above, a protective material may be placed between the retardation layer and the pressure-sensitive adhesive layer. By arranging the protective material, for example, the influence of other layers on the retardation layer can be reduced.

The protective material is, for example, a solidified product or a thermoset product of a coating film of an organic solvent solution of a resin. According to such a configuration, for example, it can be formed directly on the retardation layer (that is, without interposing an adhesive layer or a pressure-sensitive adhesive layer). Moreover, the thickness of the resulting protective material can be reduced. The thickness of the protective material is preferably 0.01 μm to 5 μm, more preferably 0.02 μm to 3 μm, still more preferably 0.03 μm to 1 μm, and particularly preferably 0.04 μm to 0.6 μm. .

式中、Ｘはビニル基、（メタ）アクリル基、スチリル基、（メタ）アクリルアミド基、ビニルエーテル基、エポキシ基、オキセタン基、ヒドロキシル基、アミノ基、アルデヒド基、および、カルボキシル基からなる群より選択される少なくとも１種の反応性基を含む官能基を表し、Ｒ^１およびＲ^２はそれぞれ独立して、水素原子、置換基を有していてもよい脂肪族炭化水素基、置換基を有していてもよいアリール基、または、置換基を有していてもよいヘテロ環基を表し、Ｒ^１およびＲ^２は互いに連結して環を形成してもよい。 In one embodiment, the resin contains more than 50 parts by weight of a (meth)acrylic monomer and more than 0 parts by weight and less than 50 parts by weight of a monomer represented by formula (1) (hereinafter , may be referred to as copolymerization monomers) and a copolymer obtained by polymerizing a monomer mixture (hereinafter referred to as a boron-containing acrylic resin in some cases).

In the formula, X is selected from the group consisting of a vinyl group, a (meth)acryl group, a styryl group, a (meth)acrylamide group, a vinyl ether group, an epoxy group, an oxetane group, a hydroxyl group, an amino group, an aldehyde group, and a carboxyl group. represents a functional group containing at least one reactive group, and R ¹ and R ² each independently represent a hydrogen atom, an optionally substituted aliphatic hydrocarbon group, or a substituted represents an aryl group which may be substituted or a heterocyclic group which may have a substituent, and R ¹ and R ² may be linked to each other to form a ring.

式中、Ｒ^６は任意の官能基を表し、jおよびｋは１以上の整数を表す。 A boron-containing acrylic resin has, for example, a repeating unit represented by the following formula. By polymerizing a monomer mixture containing a copolymerizable monomer represented by formula (1) and a (meth)acrylic monomer, the boron-containing acrylic resin has a substituent containing boron in the side chain (e.g., repeating unit k in the following formula). The boron-containing substituent may be included continuously (that is, in blocks) in the boron-containing acrylic resin, or may be included randomly.

^In the formula, R6 represents an arbitrary functional group, j and k represent integers of 1 or more.

<(Meth) acrylic monomer>
Any appropriate (meth)acrylic monomer can be used as the (meth)acrylic monomer. Examples thereof include (meth)acrylic acid ester-based monomers having a linear or branched structure and (meth)acrylic acid ester-based monomers having a cyclic structure. In addition, in this specification, (meth)acryl refers to acryl and/or methacryl.

Examples of (meth)acrylic ester-based monomers having a linear or branched structure include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and (meth)acrylic acid. isopropyl, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, methyl 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate and the like. . Preferably, methyl (meth)acrylate is used. The (meth)acrylic acid ester-based monomers may be used alone or in combination of two or more.

Examples of (meth)acrylic ester-based monomers having a cyclic structure include cyclohexyl (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, 1-adamantyl (meth)acrylate, ( meth)dicyclopentenyl acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentanyl (meth)acrylate, biphenyl (meth)acrylate, o-biphenyloxyethyl (meth)acrylate, o-biphenyloxyethoxy Ethyl (meth)acrylate, m-biphenyloxyethyl acrylate, p-biphenyloxyethyl (meth)acrylate, o-biphenyloxy-2-hydroxypropyl (meth)acrylate, p-biphenyloxy-2-hydroxypropyl (meth)acrylate , m-biphenyloxy-2-hydroxypropyl (meth)acrylate, N-(meth)acryloyloxyethyl-o-biphenyl=carbamate, N-(meth)acryloyloxyethyl-p-biphenyl=carbamate, N-(meth) Acryloyloxyethyl-m-biphenyl=carbamate, biphenyl group-containing monomers such as o-phenylphenol glycidyl ether acrylate, terphenyl (meth)acrylate, o-terphenyloxyethyl (meth)acrylate and the like. Preferably, 1-adamantyl (meth)acrylate and dicyclopentanyl (meth)acrylate are used. A polymer having a high glass transition temperature can be obtained by using these monomers. These monomers may be used alone or in combination of two or more.

A silsesquioxane compound having a (meth)acryloyl group may be used instead of the (meth)acrylic acid ester-based monomer. By using a silsesquioxane compound, an acrylic polymer having a high glass transition temperature can be obtained. Silsesquioxane compounds are known to have various skeleton structures, such as cage structures, ladder structures, and random structures. The silsesquioxane compound may have only one of these structures, or may have two or more. Silsesquioxane compounds may be used alone or in combination of two or more.

As a silsesquioxane compound containing a (meth)acryloyl group, for example, MAC grade and AC grade of Toagosei Co., Ltd. SQ series can be used. MAC grade is a silsesquioxane compound containing a methacryloyl group, and specific examples thereof include MAC-SQ TM-100, MAC-SQ SI-20, MAC-SQ HDM and the like. AC grade is a silsesquioxane compound containing an acryloyl group, and specific examples thereof include AC-SQ TA-100 and AC-SQ SI-20.

The (meth)acrylic monomer is used in an amount exceeding 50 parts by weight with respect to 100 parts by weight of the monomer mixture.

<Comonomer>
A monomer represented by the above formula (1) is used as the comonomer. By using such a comonomer, a substituent containing boron is introduced into the side chain of the resulting polymer. Comonomers may be used alone or in combination of two or more.

As the aliphatic hydrocarbon group in the above formula (1), a linear or branched alkyl group having 1 to 20 carbon atoms which may have a substituent, 3 to 3 carbon atoms which may have a substituent 20 cyclic alkyl groups and alkenyl groups having 2 to 20 carbon atoms. Examples of the aryl group include an optionally substituted phenyl group having 6 to 20 carbon atoms and a naphthyl group having 10 to 20 carbon atoms which may have a substituent. The heterocyclic group includes a 5- or 6-membered ring group containing at least one optionally substituted heteroatom. R ¹ and R ² may be linked together to form a ring. R ¹ and R ² are preferably a hydrogen atom or a linear or branched alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom.

Reactive groups contained in the functional group represented by X include vinyl group, (meth)acryl group, styryl group, (meth)acrylamide group, vinyl ether group, epoxy group, oxetane group, hydroxyl group, amino group, aldehyde group, and at least one selected from the group consisting of carboxyl groups. Preferably, the reactive groups are (meth)acryl and/or (meth)acrylamide groups.

In one embodiment, the functional group represented by X is preferably a functional group represented by ZY-. Here, Z is selected from the group consisting of a vinyl group, a (meth)acryl group, a styryl group, a (meth)acrylamide group, a vinyl ether group, an epoxy group, an oxetane group, a hydroxyl group, an amino group, an aldehyde group, and a carboxyl group. and Y represents a phenylene group or an alkylene group.

Specifically, the following compounds can be used as the comonomer.

The comonomer is used in a content of more than 0 parts by weight and less than 50 parts by weight with respect to 100 parts by weight of the monomer mixture. It is preferably 0.01 to 50 parts by weight, more preferably 0.05 to 20 parts by weight, even more preferably 0.1 to 10 parts by weight, and particularly preferably 0.1 part by weight to 10 parts by weight. 5 to 5 parts by weight.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these Examples. In addition, thickness is the value measured by the following measuring method. In addition, unless otherwise specified, "parts" and "%" in Examples and Comparative Examples are by weight.
<Thickness>
The thickness of 10 μm or less was measured using a scanning electron microscope (manufactured by JEOL Ltd., product name “JSM-7100F”). A thickness exceeding 10 μm was measured using a digital micrometer (manufactured by Anritsu Co., Ltd., product name “KC-351C”).

[Example 1]
(Preparation of polarizing plate)
As a thermoplastic resin substrate, a long amorphous isophthalic copolymerized polyethylene terephthalate film (thickness: 100 μm) having a Tg of about 75° C. was used, and one side of this resin substrate was subjected to corona treatment. .
Polyvinyl alcohol (degree of polymerization: 4,200, degree of saponification: 99.2 mol%) and acetoacetyl-modified PVA (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name "GOSEFIMER") were mixed at a ratio of 9:1, and 100 parts by weight of PVA-based resin. was added with 13 parts by weight of potassium iodide and dissolved in water to prepare an aqueous PVA solution (coating solution).
The above PVA aqueous solution was applied to the corona-treated surface of the resin base material and dried at 60° C. to form a PVA-based resin layer having a thickness of 13 μm, thereby producing a laminate.
The resulting laminate was uniaxially stretched 2.4 times in the machine direction (longitudinal direction) in an oven at 130° C. (in-air auxiliary stretching treatment).
Next, the laminate was immersed in an insolubilizing bath (an aqueous boric acid solution obtained by mixing 4 parts by weight of boric acid with 100 parts by weight of water) at a liquid temperature of 40° C. for 30 seconds (insolubilizing treatment).
Then, the finally obtained polarizer is added to a dyeing bath (iodine aqueous solution obtained by blending iodine and potassium iodide at a weight ratio of 1:7 with respect to 100 parts by weight of water) at a liquid temperature of 30 ° C. It was immersed for 60 seconds while adjusting the concentration so that the single transmittance (Ts) was a desired value (dyeing treatment).
Next, it was immersed for 30 seconds in a cross-linking bath at a liquid temperature of 40°C (an aqueous solution of boric acid obtained by blending 3 parts by weight of potassium iodide and 5 parts by weight of boric acid with respect to 100 parts by weight of water). (crosslinking treatment).
After that, while immersing the laminate in an aqueous solution of boric acid (boric acid concentration: 4% by weight, potassium iodide concentration: 5% by weight) at a liquid temperature of 70° C., the laminate was moved vertically (longitudinally) between rolls with different peripheral speeds. Uniaxial stretching was performed so that the stretching ratio was 5.5 times (underwater stretching treatment).
After that, the laminate was immersed in a washing bath (aqueous solution obtained by blending 4 parts by weight of potassium iodide with 100 parts by weight of water) at a liquid temperature of 20° C. (washing treatment).
Thereafter, while drying in an oven maintained at about 90° C., it was brought into contact with a heating roll made of SUS whose surface temperature was maintained at about 75° C. (dry shrinkage treatment).
In this way, a polarizer having a thickness of about 5 μm was formed on the resin substrate to obtain a laminate having a structure of resin substrate/polarizer.

On the polarizer side of the obtained laminate, a HC-TAC film (thickness: 32 μm) is attached as a first protective layer via a polyvinyl alcohol-based adhesive. , “RP109F,” a base material (PET) having a thickness of 38 μm and an adhesive layer having a thickness of 10 μm). The HC-TAC film is a film in which a hard coat (HC) layer (7 μm thick) is formed on a TAC film (25 μm thick), and the HC-TAC film is attached so that the polarizer side faces the HC-TAC film.
Next, the resin base material is peeled off from the polarizer, and a TAC film (thickness: 20 μm) having an Re(550) of 0 nm is attached to the other side of the polarizer as a second protective layer, and a surface protective film having a thickness of 30 μm is attached. (manufactured by Toray Industries, Inc., "Toretec") were pasted together.
Thus, a polarizing plate was obtained.

(Production of laminate)
Polymerizable liquid crystal compound (L-1) 42 parts by weight, polymerizable liquid crystal compound (L-2) 42 parts by weight, polymerizable liquid crystal compound (L-3) 16 parts by weight, polymerization initiator (PI-1) 0.5 0.09 parts by weight of polymer (T-1), 0.04 parts by weight of polymer (T-2) and 235 parts by weight of cyclopentanone were mixed to obtain a composition. The resulting composition is applied onto a cycloolefin resin (COP) film (substrate: thickness 80 μm) having an orientation film formed thereon to form a coating film, and the formed coating film is heated to 180° C., Then cool to 120 ° C., irradiate the coating film with ultraviolet rays of 100 mJ / cm ² at a wavelength of 365 nm using a high pressure mercury lamp in a nitrogen atmosphere, and form a first retardation layer (thickness 2.3 μm) on the substrate. formed. The in-plane retardation Re(550) of the obtained first retardation layer was 140 nm, and Re(450)/Re(550) was 0.87.

Polymerizable liquid crystal compound (L-1)

Polymerizable liquid crystal compound (L-2)

Polymerizable liquid crystal compound (L-3)

Polymerization initiator (PI-1)

Polymer (T-1)

Polymer (T-2)

On the first retardation layer, a 38 μm thick release film (manufactured by Toray Industries, Inc., “K Therapyal”, PET film) is pasted and laminated via an acrylic pressure-sensitive adhesive layer (thickness 7 μm) while being conveyed by a roll. got stuff

After cutting both ends of the obtained laminate in the width direction, the release film was peeled off from the laminate (adhesive layer), and the laminate was bonded to the polarizing plate while being conveyed by rolls. Specifically, the polarizing plate was attached so that the angle formed by the absorption axis of the polarizer of the polarizer and the slow axis of the first retardation layer was 45°.

<Evaluation: peel strength>
A sample having a width of 25 mm and a length of 150 mm was cut from the obtained laminate, left in an environment of 23° C. and 50% RH for 30 minutes or longer, and peeled at a peel rate of 300 mm/min and 1000 mm using a universal tensile tester. /min, and the peel force (N/25 mm) when peeled in the longitudinal direction at peel angles of 90° and 180° was measured. Specifically, the peeling force F1 of the release film from the adhesive layer and the peeling force F2 of the first retardation layer from the substrate were measured. In addition, the measurement was performed under the environment of 23° C.×50% RH.
The results obtained are summarized in Table 1.

At a peeling angle of 180°, when the peeling film is peeled from the pressure-sensitive adhesive layer, the possibility of peeling between the first retardation layer and the substrate is extremely low.

A polarizing plate with a retardation layer obtained by an embodiment of the present invention is used as a polarizing plate with a retardation layer of an image display device, and is also suitable for a curved, bendable, foldable, or windable image display device. can be used for Typical image display devices include liquid crystal display devices, organic EL display devices, and inorganic EL display devices.

REFERENCE SIGNS LIST 11 substrate 12 substrate 20 retardation layer 21 first retardation layer 22 second retardation layer 30 adhesive layer 40 release film 50 protective material 60 surface protection film 69 polarizer 70 polarizing plate 71 first protective layer 72 second Protective layer 80 Adhesive layer 90 Release film 100 Laminate 110 Retardation layer-attached polarizing plate

Claims (13)

Preparing a laminate comprising, in this order, a release film, an adhesive layer, a first retardation layer, and a base material arranged adjacent to the first retardation layer;
peeling the release film from the pressure-sensitive adhesive layer; and
laminating the laminate to a polarizing plate, in this order;
A method for producing a polarizing plate with a retardation layer. 2. The production method according to claim 1, wherein the release film is released in a direction of 120° to 180° with respect to the surface of the pressure-sensitive adhesive layer. 3. The manufacturing method according to claim 1, further comprising peeling off the substrate from the first retardation layer after bonding the laminate to the polarizing plate. The manufacturing method according to any one of claims 1 to 3, wherein the peeling force of the release film from the pressure-sensitive adhesive layer is smaller than the peeling force of the first retardation layer from the substrate. The ratio (F1/F2) of the peeling force F1 of the peeling film to the pressure-sensitive adhesive layer to the peeling force F2 of the first retardation layer to the substrate is 1 when the peeling speed is 1000 mm / sec and the peeling angle is 180 °. 5. The manufacturing method according to any one of claims 1 to 4, which is 1 or more when the peel speed is 1000 mm/sec and the peel angle is 90°. cutting an edge of the laminate before laminating the laminate to the polarizing plate;
By the cutting, the end surface of the adhesive layer and the end surface of the first retardation layer are flush,
The manufacturing method according to any one of claims 1 to 5. The manufacturing method according to claim 6, wherein the release film is peeled from the adhesive layer after the cutting. 8. The manufacturing method according to any one of claims 1 to 7, wherein an identification code is formed on the edge of the polarizing plate. 9. The manufacturing method according to any one of claims 1 to 8, wherein the first retardation layer is an alignment fixed layer of a liquid crystal compound. The manufacturing method according to any one of claims 1 to 9, wherein the first retardation layer has a thickness of 5 µm or less. The manufacturing method according to any one of claims 1 to 10, wherein the pressure-sensitive adhesive layer has a thickness of 10 µm or less. The manufacturing method according to any one of claims 1 to 11, wherein the pressure-sensitive adhesive layer has a thickness of 6 µm or more. 13. The manufacturing method according to any one of claims 1 to 12, further comprising laminating a second retardation layer after bonding the laminate to the polarizing plate.

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