Method for producing phase difference layer intermediate and method for producing polarizing plate with phase difference layer

Abstract

Provided are a method with which it is possible to efficiently produce a phase difference layer intermediate and a polarizing plate with a phase difference layer, said phase difference layer intermediate having extremely precisely controlled slow axis direction. A method for manufacturing a phase difference layer according to an embodiment of the present invention includes punching a raw film roll of a phase difference film having a slow axis to a predetermined size while correcting an offset of the slow axis in a width direction of the raw film roll with respect to a longitudinal direction of the raw film roll; a monolithic phase difference layer intermediate having a slow axis in the longitudinal direction is obtained.

Description

Technical Field

[0001] The present invention relates to a method for producing a phase difference layer intermediate and a method for producing a polarizing plate with a phase difference layer. Background Art

[0002] Image display devices represented by liquid crystal display devices and electroluminescent (EL) display devices (for example, organic EL display devices, inorganic EL display devices) are rapidly becoming popular. In image display devices, in order to achieve image display and / or improve the performance of the image display, a polarizer with a phase difference layer including a polarizer and a phase difference film (phase difference layer) has been widely used. On the other hand, new uses of image display devices have been developed in recent years. As an example of such a use, virtual reality (VR) goggles can be cited. In the case of a polarizer with a phase difference layer used in VR goggles, its size is significantly smaller than in previous uses. As a result, the axial offset of the slow axis of the phase difference layer, which has not been a problem in previous uses, has become a substantial problem.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-182162 Summary of the invention

[0006] Problems to be solved by the invention

[0007] The present invention has been made to solve the above-mentioned problems, and its main object is to provide a method for efficiently producing a phase difference layer intermediate and a polarizing plate with a phase difference layer in which the slow axis direction is extremely precisely controlled.

[0008] Solutions to the problem

[0009] The manufacturing method of the phase difference layer intermediate of the embodiment of the present invention includes: for an original film roll of a phase difference film having a slow axis, while correcting the offset of the slow axis relative to the length direction in the width direction of the original film roll, it is punched into a given size to obtain a single-piece phase difference layer intermediate having a slow axis in the long side direction.

[0010] In one embodiment, the retardation film has a slow axis in the longitudinal direction of the original film roll.

[0011] The method for manufacturing a polarizing plate with a phase difference layer in another aspect of the present invention comprises: laminating a phase difference layer intermediate manufactured by the above-mentioned method for manufacturing a phase difference layer intermediate with a polarizing plate intermediate to obtain a polarizing plate intermediate with a phase difference layer; and punching the polarizing plate intermediate with a phase difference layer to obtain a polarizing plate sheet with a phase difference layer of a given size.

[0012] Effects of the Invention

[0013] According to the embodiment of the present invention, it is possible to realize a method for efficiently producing a phase difference layer intermediate and a polarizing plate with a phase difference layer in which the slow axis direction is extremely precisely controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 (a) and (b) are schematic diagrams for explaining a method for producing a phase difference layer intermediate according to an embodiment of the present invention.

[0015] Figure 2 (a) to (c) are schematic diagrams for explaining the process of obtaining a polarizing plate intermediate in the method for producing a polarizing plate with a retardation layer according to an embodiment of the present invention.

[0016] Figure 3 (a) to (c) are schematic diagrams for explaining the process of obtaining a polarizing plate sheet with a retardation layer as a final product in the method for producing a polarizing plate with a retardation layer according to an embodiment of the present invention.

[0017] Explanation of symbols

[0018] 10 Original film roll of phase difference film

[0019] 12 Phase difference layer intermediate

[0020] 20 Polarizer original film roll

[0021] 22 Polarizer Intermediates

[0022] 30 Polarizer intermediate with phase difference layer

[0023] 32 Polarizing plate sheet with phase difference layer (polarizing plate with phase difference layer as final product) DETAILED DESCRIPTION

[0024] Hereinafter, the 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, all the drawings are schematic and do not accurately depict actual conditions.

[0025] A. Overview of the method for producing a phase difference layer intermediate and the method for producing a polarizing plate with a phase difference layer

[0026] The manufacturing method of the phase difference layer intermediate of the embodiment of the present invention includes: for an original film roll of a phase difference film having a slow axis, while correcting the offset of the slow axis relative to the length direction in the width direction of the original film roll, it is punched into a given size to obtain a single-piece phase difference layer intermediate having a slow axis in the long side direction.

[0027] In addition, the method for manufacturing a polarizing plate with a phase difference layer according to another aspect of the present invention includes: laminating a phase difference layer intermediate manufactured by the above-mentioned method for manufacturing a phase difference layer intermediate with a polarizing plate intermediate to obtain a polarizing plate intermediate with a phase difference layer (for convenience, referred to as a polarizing plate intermediate manufacturing process with a phase difference layer); and punching the polarizing plate intermediate with a phase difference layer to obtain a polarizing plate sheet with a phase difference layer of a given size (for convenience, referred to as a final process).

[0028] Hereinafter, each step will be described in detail.

[0029] B. Method for producing a phase difference layer intermediate

[0030] Figure 1 (a) and Figure 1 (b) is a schematic diagram for explaining a method for producing a phase difference layer intermediate.

[0031] First, if Figure 1 As shown in (a), prepare the original film roll of the phase difference film. The phase difference film is typically a stretched film of a resin film. Representative examples of the resin constituting the phase difference film include polycarbonate resins, polyester carbonate resins, polyester resins, polyvinyl acetal resins, polyarylate resins, cyclic olefin resins, cellulose resins, polyvinyl alcohol resins, polyamide resins, polyimide resins, polyether resins, polystyrene resins, and acrylic resins.

[0032] The optical properties of the retardation film can be appropriately set according to the purpose. The retardation film has a slow axis and shows a relationship of nx>ny. The retardation film shown in the figure has a slow axis in the longitudinal direction of the roll.

[0033] The phase difference film typically shows a refractive index characteristic of nx>ny≥nz. The phase difference film can typically function as a λ / 4 plate. The in-plane phase difference Re(550) of the phase difference film is preferably 100nm to 200nm, more preferably 110nm to 180nm, and further preferably 130nm to 150nm. By making the phase difference film function as a λ / 4 plate, the phase difference film and the polarizer (polarizer) are stacked in a manner such that the slow axis of the phase difference film and the absorption axis of the polarizer are typically at an angle of 45°, thereby obtaining a polarizer (circular polarizer) with a phase difference layer having an excellent anti-reflection function. Here, "Re(λ)" is the in-plane phase difference measured at 23°C with light of a wavelength of λnm. Therefore, "Re(550)" is the in-plane phase difference measured at 23°C with light of a wavelength of 550nm. When the thickness of the layer (film) is set to d(nm), Re(λ) can be obtained by the formula: Re(λ)=(nx-ny)×d.

[0034] The phase difference film can exhibit reverse wavelength dispersion characteristics in which the phase difference value increases according to the wavelength of the measuring light, positive wavelength dispersion characteristics in which the phase difference value decreases according to the wavelength of the measuring light, or flat wavelength dispersion characteristics in which the phase difference value hardly changes with the wavelength of the measuring light.

[0035] The thickness of the retardation film can be set so that it can optimally function as a λ / 4 plate. In other words, the thickness can be set so that the above-mentioned desired in-plane retardation is obtained. Specifically, the thickness is preferably 70 μm or less, preferably 15 μm to 60 μm.

[0036] like Figure 1 As shown in (a), the phase difference film typically has an axial offset in the width direction in the original film roll 10. In more detail, the direction of the slow axis S of the phase difference film is mostly offset by a given angle relative to the length direction of the roll at the width direction end of the roll. Typically, the axial offset is not substantially manifested in the central part, but becomes larger as it approaches the width direction end. The axial offset at the width direction end will change according to the width of the roll. For example, in a roll with a width of about 1000mm to 1500mm, the axial offset at the width direction end can be, for example, 1° to 3°. In the case of making a large (for example, for TV) polarizing film with a phase difference layer, such an axial offset will not become a substantial problem. This is because, by improving the color unevenness and viewing angle dependence of the polarizing film with a phase difference layer as a whole, the problem of axial offset will not surface or worsen. On the other hand, the inventors of the present invention have newly discovered that in the case of making a very small (for example, for VR goggles: a size of about 20mm×30mm) polarizing film with a phase difference layer, the deviation of the characteristics of each final product caused by such an axial offset becomes unacceptably large. Furthermore, the inventors of the present invention have made continuous attempts to solve this problem, and found that the axial deviation of the slow axis of the phase difference film is more dominant than the axial deviation of the absorption axis of the polarizer, and that the problem can be solved by adopting a manufacturing process that appropriately eliminates the axial deviation of the slow axis of the phase difference film, thereby completing the present invention. That is, the embodiment of the present invention can solve a new problem that has not been recognized so far, and the effect is an unexpected excellent effect.

[0037] In the illustrated retardation film, the slow axis S of the retardation film is substantially parallel to the longitudinal direction of the roll in the widthwise center (axis deviation is less than 0°±1°), but the direction of the slow axis S of the retardation film is not limited thereto.

[0038] In the central part of the width direction of the phase difference film, the slow axis S of the phase difference film may also be crossed with respect to the length direction. In this case, the slow axis direction of the end portion of the phase difference film in the width direction is offset relative to the slow axis direction of the central portion in the width direction due to the above-mentioned axis offset. For example, the angle between the slow axis S at the end portion in the width direction and the length direction is greater than the angle between the slow axis S in the central portion and the length direction (for example, 45°) by a given angle (for example, 1° to 3°) or less than a given angle (for example, 1° to 3°). It should be noted that if the slow axis S in the central portion in the width direction is crossed with respect to the length direction, there is a risk of increased deviation in the slow axis direction between the phase difference layer intermediates compared to the above-mentioned example. Therefore, the above-mentioned example is more preferred.

[0039] In an embodiment of the present invention, Figure 1 As shown in (a), the original film roll 10 is punched into a given size while correcting the deviation of the slow axis S in the width direction relative to the length direction, so that Figure 1 As shown in (b), a single (typically rectangular) retardation layer intermediate 12 having a slow axis S in the longitudinal direction is obtained. The retardation layer intermediate 12 is a single (typically rectangular) retardation film punched out from the long retardation film constituting the original film roll 10 .

[0040] In more detail, it is as follows. First, the axial deviation of the slow axis S of the original film roll 10 is detected. As a method for detecting the axial deviation, any appropriate means can be used. For example, the axial deviation can be detected by measuring the axial angle using "AxoScan" manufactured by Axometrics. When the axial deviation is detected, the direction of the punching knife is adjusted based on the detected information, and the punching knife with the adjusted direction is used to punch a given part of the original film roll.

[0041] Representatively, after detecting the slow axis S at a given portion of the original film roll, the direction of the punching knife is adjusted in such a manner that the punched phase difference layer intermediate 12 includes the detection object portion and the detected slow axis S is substantially parallel to the long side direction (length direction) of the phase difference layer intermediate 12 (the angle between the slow axis S and the long side direction is 0°±1°).

[0042] As a result, if Figure 1 As shown in (b), no matter where the punching position of the original film roll is, a phase difference layer intermediate 12 can be obtained which has a slow axis S in the long side direction (that is, the slow axis direction is precisely controlled) and the deviation in the slow axis direction between each phase difference layer intermediate is very small (essentially no deviation).

[0043] By correcting the axial deviation of the slow axis of the original film roll when making the phase difference layer intermediate, the deviations in the directions of the slow axes are substantially eliminated in the phase difference layer intermediate, thereby making it extremely simple and easy to control the axial direction when making the polarizer intermediate with phase difference layer and the polarizer sheet with phase difference layer (the polarizer with phase difference layer as the final product) described later.

[0044] exist Figure 1 (a) illustrates an example of punching out three phase difference layer intermediates from the original film roll in the width direction, but in an embodiment of the present invention, representatively, 3 to 16 phase difference layer intermediates, and 5 to 6 phase difference layer intermediates, can be punched out from the original film roll in the width direction. If such a structure is used, the manufacturing efficiency is excellent, the waste of the original film roll is small, and the phase difference layer intermediate with the axial deviation of the original film roll properly corrected can be obtained. In this case, the obtained phase difference layer intermediate can be, for example, a rectangle with a short side of about 75mm to 310mm, and can also be, for example, a rectangle with a long side of 250mm to 350mm and a short side of about 150mm to 250mm.

[0045] The punching of the phase difference layer intermediate body may be performed for each sheet while correcting the axis deviation, or may be performed for each row in the width direction while adjusting the directions of a predetermined number of punching blades.

[0046] C. Production process of polarizing plate intermediate with phase difference layer

[0047] In the step of producing the polarizing plate intermediate with a retardation layer, the retardation layer intermediate obtained as described in the above section B is bonded to the polarizing plate intermediate.

[0048] like Figure 2 As shown in (a), typically, the polarizer intermediate can be obtained by punching the original film roll 20 of the polarizer having an absorption axis in the longitudinal direction into the same size as the above-mentioned phase difference layer intermediate. Typically, the polarizer intermediate has an absorption axis in a direction of 45° relative to the long side direction. It should be noted that in this specification, the description of "absorption axis of polarizer" refers to the absorption axis of the polarizer contained in the polarizer.

[0049] The polarizing plate typically has a polarizer and a protective film provided on at least one side of the polarizer. As the polarizer, any appropriate polarizer can be used. The resin film forming the polarizer can be a single-layer resin film, or it can be made using a laminate of two or more layers. As a specific example of a polarizer composed of a single-layer resin film, there can be cited polarizers obtained by dyeing and stretching hydrophilic polymer films such as polyvinyl alcohol (PVA) resin films, partially formalized PVA resin films, and partially saponified films of ethylene-vinyl acetate copolymers using dichroic substances such as iodine and dichroic dyes; polyene oriented films such as dehydrated PVA and dehydrochlorinated polyvinyl chloride. Due to its excellent optical properties, it is preferred to use a polarizer obtained by dyeing a PVA resin film with iodine and uniaxially stretching it. The above-mentioned dyeing with iodine can be performed, for example, by immersing the PVA resin film in an iodine aqueous solution. The stretching ratio of the above-mentioned uniaxial stretching is preferably 3 to 7 times. Stretching can be performed after dyeing or while dyeing. In addition, dyeing can be performed after stretching. PVA resin film can be subjected to swelling treatment, cross-linking treatment, cleaning treatment, drying treatment, etc. as required. For example, by immersing the PVA resin film in water and washing it before dyeing, not only can dirt and anti-blocking agent on the surface of the PVA resin film be cleaned, but also the PVA resin film can be swollen to prevent uneven dyeing.

[0050] As a specific example of a polarizer obtained using a laminate, there can be cited a laminate using a resin substrate and a PVA-type resin layer (PVA-type resin film) laminated on the resin substrate, or a polarizer obtained using a laminate using a resin substrate and a PVA-type resin layer formed by coating on the resin substrate. The polarizer obtained using a laminate using a resin substrate and a PVA-type resin layer formed by coating on the resin substrate can be made by the following method: for example, a PVA-type resin solution is applied to a resin substrate, and the PVA-type resin layer is formed on the resin substrate by drying, thereby obtaining a laminate of the resin substrate and the PVA-type resin layer; the laminate is stretched and dyed to make the PVA-type resin layer into a polarizer. In the present embodiment, stretching typically includes immersing the laminate in an aqueous boric acid solution for stretching. In addition, stretching may further include stretching the laminate in a gas atmosphere at a high temperature (for example, above 95°C) before stretching in an aqueous boric acid solution, as needed. The obtained laminate of resin substrate / polarizer can be used directly (that is, the resin substrate can be made into a protective layer of polarizer), or the resin substrate can be peeled off from the laminate of resin substrate / polarizer, and any appropriate protective layer corresponding to the purpose can be laminated on the peeled surface for use. The details of the manufacturing method of such a polarizer are described in, for example, Japanese Patent Publication No. 2012-73580 and Japanese Patent No. 6470455. The descriptions of these patent documents are cited in this specification as reference.

[0051] The protective film can be made of any suitable film that can be used as a protective film for a polarizer. As a specific example of the material that becomes the main component of the film, cellulose resins such as triacetyl cellulose (TAC), polyesters, polyvinyl alcohols, polycarbonates, polyamides, polyimides, polyether sulfones, polysulfones, polystyrenes, polynorbornenes, polyolefins, cyclic olefins, (meth) acrylic acid, transparent resins such as acetates, etc. can be cited. In addition, thermosetting resins or ultraviolet curing resins such as (meth) acrylic acid, carbamates, (meth) acrylic acid carbamates, epoxies, silicones, etc. can also be cited. In addition, glassy polymers such as siloxane polymers can also be cited. In addition, the polymer film described in Japanese Patent Publication No. 2001-343529 (WO01 / 37007) can also be used. As the material of the film, for example, a resin composition containing a thermoplastic resin having a substituted or unsubstituted imide group in the side chain and a thermoplastic resin having a substituted or unsubstituted phenyl and nitrile group in the side chain can be used, and for example, a resin composition having an alternating copolymer formed by isobutylene and N-methylmaleimide and an acrylonitrile-styrene copolymer can be mentioned. The polymer film can be, for example, an extrusion molding of the above resin composition. TAC, (meth) acrylic resin, and cyclic olefin resin can be preferably used.

[0052] like Figure 2 As shown in (a), representatively, the polarizer has substantially no axial offset in the width direction in the original film roll 20. In more detail, for the polarizer, due to the material, optical properties, manufacturing method, etc., the direction of its absorption axis A in the width direction of the original film roll as a whole will appear as a direction substantially parallel to the length direction of the original film roll. That is, the axial offset of the absorption axis of the polarizer in the width direction does not substantially exist, or even if it exists, it is very small relative to the axial offset of the slow axis of the phase difference film. Therefore, when making the polarizer intermediate 22 from the original film roll 20 of the polarizer, it is not necessary to perform punching while correcting the axial offset. As a result, in an embodiment of the present invention, by using, for example, a lattice-shaped punching knife, it is possible to Figure 2 As shown in (b), a plurality of polarizing plate intermediates are punched out at once. In the example shown in the figure, by punching out in a direction of 45° relative to the longitudinal direction of the original film roll, Figure 2As shown in (c), a single (representatively rectangular) polarizer intermediate 22 having an absorption axis A in a direction of 45° relative to the long side direction is obtained. By punching out a plurality of polarizer intermediates in this way, excellent manufacturing efficiency can be achieved. In addition, if each sheet is punched out in an inclined direction (in a direction at a given angle relative to the length direction of the original film roll), sometimes even if there is no axial deviation in the original film roll, there will be axial deviations between the punched-out intermediates, and such problems can be avoided by punching out together. That is, a polarizer intermediate 22 in which the absorption axis direction is precisely controlled and the deviation in the absorption axis direction between the intermediates is very small (substantially no deviation) can be obtained. The polarizer intermediate 22 is a single (representatively rectangular) polarizer punched out of the long strip of polarizer constituting the original film roll 20. It should be noted that the punching angle (angle relative to the length direction of the original film roll) can be appropriately set according to the purpose in addition to 45°, which is obvious to those skilled in the art. This angle corresponds to the angle formed by the absorption axis of the polarizer in the polarizing plate intermediate with a retardation layer and the slow axis of the retardation layer.

[0053] The above-mentioned oblique punching can be typically performed as follows: the edge in the width direction of the original film roll is detected, the direction of the punching blade is adjusted based on the detected information, and the punching is performed with the punching blade with the adjusted direction.

[0054] The size of the punched polarizer intermediate is typically the same as the size of the phase difference layer intermediate. Therefore, the obtained polarizer intermediate can be, for example, a rectangle with a short side of about 75mm to 310mm, and can also be, for example, a rectangle with a long side of 250mm to 350mm and a short side of about 150mm to 250mm. If it is such a structure, as described later, the preparation of the polarizer intermediate with a phase difference layer is simple and easy, and the absorption axis of the polarizer in the polarizer intermediate with a phase difference layer and the angle of the slow axis of the phase difference layer (phase difference film) are easy to control.

[0055] Next, if Figure 3As shown in (a), the above-mentioned phase difference layer intermediate 12 and the above-mentioned polarizer intermediate 22 are bonded in a manner that the angle between the absorption axis of the polarizer and the slow axis of the phase difference layer is 45°, thereby obtaining a polarizer intermediate with a phase difference layer. The phase difference layer intermediate and the polarizer intermediate are typically bonded in a manner that their respective outer edges are consistent. As described above, the phase difference layer intermediate and the polarizer intermediate are both precisely controlled in the axial direction, and the axial deviation of the phase difference layer intermediate and the polarizer intermediate is very small. Therefore, by bonding in a manner that their respective outer edges are consistent, the angle between the absorption axis of the polarizer in the polarizer intermediate with a phase difference layer and the slow axis of the phase difference layer can be well controlled without performing precise and / or delicate operations. In addition, it is undoubtedly that such an operation is simple and easy, and therefore, the preparation of the polarizer intermediate with a phase difference layer itself is simple and easy. In this manner, a polarizing plate intermediate with a retardation layer can be obtained in which the retardation layer has a slow axis in the longitudinal direction and the angle formed between the absorption axis of the polarizer and the slow axis of the retardation layer is 45°.

[0056] D. Final process

[0057] Next, if Figure 3 (b) and Figure 3 As shown in (c), the polarizer intermediate 30 with a phase difference layer obtained as described in the above item C is punched out to obtain a polarizer sheet with a phase difference layer (a polarizer with a phase difference layer as a final product) 32. Punching is typically performed in a direction of 45° relative to the long side direction of the polarizer intermediate with a phase difference layer. As a result, Figure 3 As shown in (c), a polarizer sheet with a phase difference layer can be obtained, in which the polarizer has an absorption axis in the long side direction and the angle between the absorption axis of the polarizer and the slow axis of the phase difference layer is 45° (a polarizer with a phase difference layer as a final product). As described above, in the polarizer intermediate with a phase difference layer, the angle between the absorption axis of the polarizer and the slow axis of the phase difference layer is well controlled. Therefore, when making a polarizer sheet 32 ​​with a phase difference layer from the polarizer intermediate 30 with a phase difference layer, it is not necessary to perform punching while correcting the axis offset. As a result, in an embodiment of the present invention, by using, for example, a lattice-shaped punching knife, Figure 3(b) As shown, multiple polarizer sheets with phase difference layers are punched out at the same time. By punching out multiple polarizer sheets with phase difference layers at the same time like this, excellent manufacturing efficiency can be achieved. In addition, if each sheet is punched out in an inclined direction (in a direction at a given angle relative to the long side direction of the polarizer intermediate with a phase difference layer), sometimes even if there is no axial offset in the polarizer intermediate with a phase difference layer, axial deviations will occur between the punched out final products, and such problems can be avoided by punching out together. That is, a polarizer sheet 32 ​​with a phase difference layer can be obtained in which the absorption axis direction and the slow axis direction are precisely controlled and these deviations between each product are very small (substantially no deviation).

[0058] The above-mentioned oblique direction punching can be typically performed as follows: the edge of the polarizer intermediate with a phase difference layer is detected, and the direction of the punching knife is adjusted based on the detected information, and the punching knife with the adjusted direction is used for punching. Preferably, the two edges of the long side and the short side of the polarizer intermediate with a phase difference layer are detected. If it is such a structure, more precise punching can be performed.

[0059] In this way, a polarizer sheet with a phase difference layer (a polarizer with a phase difference layer as a final product) 32 can be obtained. The obtained polarizer sheet with a phase difference layer can be, for example, a long side of 10 mm to 70 mm and a short side of about 10 mm to 70 mm, and can also be, for example, a long side of 20 mm to 40 mm and a short side of about 10 mm to 30 mm, and more specifically, a rectangle with a long side of 30 mm and a short side of about 20 mm. Such a polarizer sheet with a phase difference layer can be used, for example, as a circular polarizer for VR goggles.

[0060] According to an embodiment of the present invention, by adopting a manufacturing process that is completely different from the past, a phase difference layer intermediate and a polarizer with a phase difference layer in which the slow axis direction is extremely precisely controlled can be effectively manufactured. In particular, the effect is significant in the manufacture of very small polarizers with phase difference layers. Specifically, as described below. In the previous manufacturing method, representatively, a phase difference layer intermediate having a slow axis in a direction inclined relative to the long side direction (for example, a 45° direction) is punched out from the original film roll of the phase difference film, and a polarizer intermediate having an absorption axis in the long side direction is punched out from the original film roll of the polarizer. This is because the yield rate becomes higher when operating like this, and the problem of axial deviation of the phase difference layer (phase difference film) in the polarizer with a phase difference layer of the previous size will not be aggravated. On the other hand, in the case of making a very small polarizer with a phase difference layer (for example, for VR goggles: a size of about 20mm×30mm), if the manufacturing method is as described above, there is a situation where the deviation of the characteristics between each final product becomes unacceptably large. According to an embodiment of the present invention, a phase difference layer intermediate having a slow axis in the long side direction is punched out from the original film roll of the phase difference film while correcting the axis offset. Representatively, a polarizer intermediate having an absorption axis in a direction inclined relative to the long side direction (for example, a 45° direction) is punched out from the original film roll of the polarizer. Thus, even if a very small polarizer with a phase difference layer is finally made, a polarizer with a phase difference layer in which the absorption axis direction of the polarizer and the slow axis direction of the phase difference layer are extremely precisely controlled can be obtained. In this case, the discarded portion of the original film roll is more than that of the previous manufacturing method, but the number of unacceptable final products is overwhelmingly reduced, so the overall yield rate is sometimes higher. Alternatively, even in the case where the overall yield rate is reduced, since the axis offset of the polarizer with a phase difference layer cannot be detected without destroying the final product (for example, VR goggles), it is useful as a quality assurance of the final product.

[0061] Industrial Applicability

[0062] The production method according to the embodiment of the present invention can be suitably used for producing a phase difference layer intermediate and a polarizing plate with a phase difference layer, and is particularly suitably used for producing a very small polarizing plate with a phase difference layer (for example, for VR goggles).

Claims

1. A method for manufacturing a phase difference layer intermediate, the method comprising: A phase difference film roll having a slow axis is punched into a predetermined size while correcting the deviation of the slow axis in the width direction of the phase difference film roll relative to the longitudinal direction, thereby obtaining a single phase difference layer intermediate having a slow axis in the longitudinal direction.

2. The method for producing a phase difference layer intermediate according to claim 1, wherein: The phase difference film has a slow axis in the longitudinal direction of the original film roll.

3. A method for manufacturing a polarizing plate with a phase difference layer, the method comprising: The phase difference layer intermediate produced by the method for producing the phase difference layer intermediate according to claim 1 or 2 is laminated to a polarizing plate intermediate to obtain a polarizing plate intermediate with a phase difference layer; as well as The polarizing plate intermediate with a retardation layer is punched out to obtain a polarizing plate sheet with a retardation layer of a given size.

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