JP2010160473A - Method and material roll for producing optical display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an optical display apparatus, with which the peeling of a polarizing plate from an optical display unit is prevented effectively with a simple constitution, and also to provide material roll for producing an optical display apparatus. <P>SOLUTION: The polarizing plate 32, which has a polarizer protective film 37 on one surface of a polarizing film and a mold releasing film 33 on the opposite surface thereof to the polarizer protective film 37 while interposing an adhesive layer 35 between the polarizing film and the mold release film, is wound while keeping the mold release film 33 inward to form the rolled original goods. The polarizing plate 32 is unwound from the material roll and cut into pieces each having prescribed size. One of the obtained pieces is stuck to an optical display unit. As a result, the polarizing plate 32 of one side protection type is allowed to have the property of being warped toward the side of the mold release film 33 with such the simple constitution that the polarizing plate 32 is wound while keeping the mold release film 33 inward. Since the polarizing plate is kept excellently in a state warped toward the side of the mold release film 33 when unwound, the peeling of the polarizing plate 32 from the optical display unit is prevented effectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical display device manufacturing method for manufacturing an optical display device by bonding a polarizing plate to an optical display unit, and an optical display device manufacturing roll.

  As an example of a general polarizing plate, a double-sided protective type polarizing plate is known in which a polarizer protective film is bonded to both surfaces of a polarizing film made of a film-like polarizer via an adhesive layer. The polarizing film is formed, for example, by drying a polyvinyl alcohol (PVA) film, and a TAC (triacetyl cellulose) film or the like is used as the polarizer protective film.

  In recent years, liquid crystal display devices, which are examples of devices using polarizing plates, have been required to be thinner and lighter, and accordingly, the polarizing plates are also desired to be thinner and lighter. Yes. Therefore, it is conceivable to reduce the thickness and weight of the polarizing plate by omitting one of the polarizer protective films bonded to both sides of the polarizing film to obtain a single-sided protective type polarizing plate.

  FIG. 4 is a cross-sectional view showing a configuration example of the single-side protection type polarizing plate 52. The polarizing plate 52 has a surface protective film 51 bonded to one surface thereof via an adhesive layer 54 and a release film 53 bonded to the other surface via an adhesive layer 55. . As shown in FIG. 4, in the single-side protection type polarizing plate 52, a polarizer protective film 57 is bonded to the surface of the polarizing film 58 having at least the polarizer on the side opposite to the release film 53. Thus, since the single-sided protection type polarizing plate 52 has the polarizer protective film 57 only on the surface opposite to the release film 53, the front and back structures are asymmetric. Therefore, there is a problem that the polarizing plate 52 is warped toward the release film 53 and the accuracy of the bonding position is deteriorated when bonding to a bonding target such as an optical display unit. Therefore, in Patent Document 1 described below, the polarizing plate is warped until the time of bonding by bonding a synthetic resin film having specific properties to the polarizing plate so as to be applied with a predetermined tension. Technologies have been proposed.

Japanese Patent No. 3368524

  However, in the technique disclosed in Patent Document 1, a synthetic resin film having specific properties must be used, and complicated control must be performed when the synthetic resin film is bonded. Therefore, there exists a problem that the manufacturing cost of a polarizing plate becomes high.

  In addition, when a polarizing plate whose warpage has been corrected by the technique disclosed in Patent Document 1 is used, tensile stress is generated in the polarizing film due to the high tension of the synthetic resin film, and the optical display unit The stress which becomes a factor of peeling acts on the bonding surface. In particular, when the polarizing plate is bonded to the optical display unit in a state where the polarizing plate is warped on the side of the polarizer protective film (the side opposite to FIG. 4), peeling is likely to occur from the end.

  The present invention has been made in view of the above circumstances, and an optical display device manufacturing method and an optical display device manufacturing roll capable of effectively preventing peeling of a polarizing plate from an optical display unit with a simple configuration. The purpose is to provide the original fabric.

  An optical display device manufacturing method according to the first aspect of the present invention is an optical display device manufacturing method for manufacturing an optical display device by laminating a polarizing plate to an optical display unit, and having a polarizer protective film on one side A roll original formed by winding a plate with the release film side bonded to the surface opposite to the polarizer protective film with respect to the polarizing plate with the release film side inward. Conveying step of feeding out the polarizing plate and the release film from the opposite side, and a cutting step of cutting the polarizing plate fed out from the roll original fabric together with the release film or leaving the release film to a predetermined size And a bonding step of bonding the polarizing plate to the optical display unit.

  According to such a configuration, the single-sided protective type polarizing plate having the property of warping toward the release film side is wound with the release film side inward, so that it is released when it is rewound. It can hold | maintain favorably in the state which curved to the film side. Thereby, it can prevent that a polarizing plate peels from the bonding surface of an optical display unit in the state which cut | disconnected the polarizing plate extended | stretched from a roll original fabric to predetermined size, and was bonded to the optical display unit. Therefore, peeling of the polarizing plate from the optical display unit can be effectively prevented with a simple configuration in which the polarizing film is wound with the release film side inward.

  Moreover, since the polarizing plate is wound with the pressure-sensitive adhesive layer side inside, it is possible to prevent dents (surface scratches) of the pressure-sensitive adhesive. Thereby, it is possible to prevent air bubbles from being mixed at the time of bonding due to the dents of the adhesive, and it is possible to omit a process such as autoclave for eliminating the air bubbles. Furthermore, by providing a polarizer protective film on one side of the polarizing plate, it is possible to reduce the manufacturing cost of the raw roll as compared with a polarizing plate having a polarizer protective film on both sides.

  The optical display device manufacturing method according to the second aspect of the present invention is characterized in that, in the bonding step, bonding is performed to the optical display unit while applying a predetermined tension to the polarizing plate.

  According to such a configuration, by applying a predetermined tension to the polarizing plate, the polarizing plate that is warped toward the release film side can be bonded to the optical display unit in a state of being straightened. Thereby, the precision of the bonding position of the polarizing plate with respect to an optical display unit can be improved.

  The roll for manufacturing an optical display device according to the third aspect of the present invention is formed by winding a polarizing plate, and is an optical display for cutting and bonding the polarizing plate to a predetermined size on an optical display unit. It is a roll for manufacturing an apparatus, and a polarizing plate having a polarizer protective film on one side is bonded to a surface opposite to the polarizer protective film with respect to the polarizing plate via an adhesive layer. It is formed by being wound with the release film side inside.

  According to such a configuration, it is possible to provide a roll for manufacturing an optical display device that has the same effect as the method for manufacturing an optical display device according to the first aspect of the present invention.

  According to the present invention, when a single-side protection type polarizing plate having a property of warping toward the release film side is rewound with a simple configuration in which the polarizing plate is wound with the release film side inside. Moreover, since it can hold | maintain favorably in the state which curved to the release film side, peeling of the polarizing plate with respect to an optical display unit can be prevented effectively. Also, since the polarizing plate is wound with the release film side inward, it can be held well in a state of warping the release film side when unwound, so that the polarizing plate passes through the transport roller Even when it is performed, it is possible to prevent the polarizing plate from being peeled off from the release film during conveyance.

5 is a flowchart illustrating an example of a method for manufacturing an optical display device according to an embodiment of the present invention. It is the schematic which showed an example of the manufacturing system of an optical display apparatus. It is sectional drawing which showed the structural example of the 1st sheet product and the 2nd sheet product. It is sectional drawing which showed the structural example of the single-sided protection type polarizing plate.

  One embodiment of the present invention will be described below. FIG. 1 is a flowchart showing an example of a method for manufacturing an optical display device according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating an example of a manufacturing system for an optical display device.

(Optical display unit)
First, examples of the optical display unit W used in the optical display device manufactured according to the present invention include a glass substrate unit of a liquid crystal cell, an organic EL light emitting unit, and the like. The optical display unit W is formed in a rectangular shape, for example.

(Polarizer)
Examples of the polarizing plate bonded to the optical display unit W of the optical display device manufactured according to the present invention include a polarizing film, a retardation film, a brightness enhancement film, and a combination laminated film of two or more of these films. However, at least the polarizing film is included. An adhesive layer is formed on one surface of the polarizing plate so as to be attached to the optical display unit W, and a release film for protecting the adhesive layer is provided. Moreover, a surface protective film is provided on the other surface of the polarizing plate via an adhesive layer. Specific configurations of these films will be described later. Hereinafter, a polarizing plate on which a surface protective film and a release film are laminated may be referred to as a sheet product.

(Manufacturing flowchart)
(1) 1st roll original fabric preparation process (FIG. 1, S1). A first roll original fabric formed by winding a strip-shaped first sheet product into a roll is prepared. The width of the first roll is dependent on the bonding size of the optical display unit W.

  (2) Transport process (FIG. 1, S2: first transport step). The first sheet material 30 is unwound from the first roll stock prepared and installed, and is conveyed downstream.

  (3) First inspection step (FIG. 1, S3). The first sheet product 30 is inspected for defects using the first defect inspection apparatus 14. The defect inspection method here includes a method of photographing and processing images with transmitted light and reflected light on both sides of the first sheet product 30, and an inspection polarizing film between the CCD camera and the inspection object. A method for taking an image and processing an image by arranging it so that it is in crossed Nicols with the polarization axis (optical axis) of the target polarizing plate (sometimes referred to as a 0 degree cross), and a polarizing film for inspection with a CCD camera and inspection target An image is taken between the object and an object so as to be at a predetermined angle (for example, a range greater than 0 degree and within 10 degrees) with the polarization axis of the polarizing plate to be inspected. -Image processing methods are listed. Note that a known method can be applied to the image processing algorithm, and for example, a defect can be detected by density determination by binarization processing.

  In the image capturing / image processing method using transmitted light, foreign matter inside the first sheet product 30 can be detected. In the image photographing / image processing method using the reflected light, the adhered foreign matter on the surface of the first sheet product 30 can be detected. In the image photographing / image processing method using the 0-degree cross, mainly surface foreign matter, dirt, internal foreign matter, etc. can be detected as bright spots. In the image photographing / image processing method using the x-degree cross, a nick can be mainly detected.

  The defect information obtained by the first defect inspection device 14 is linked with the position information (for example, position coordinates), transmitted to the control device, and can contribute to the cutting method by the first cutting device 16. .

  (4) First cutting step (FIG. 1, S4: first cutting step). The first cutting device 16 includes a first polarizing plate to which the first release film is bonded without cutting the first release film, and a surface protective film that is bonded to the first polarizing plate. Is cut into a predetermined size. At this time, the adhesive layer formed between the first release film and the first polarizing plate may or may not be cut. Examples of the cutting means include a laser device, a cutter, and other known cutting means. It is preferable that the apparatus is configured to cut so as to avoid the defect based on the defect information obtained by the first defect inspection apparatus 14. Thereby, the yield of the first sheet product 30 is significantly improved. The first sheet product 30 including the defect is configured to be excluded by a first rejection device (not shown) and not attached to the optical display unit W.

  Each of the first roll original fabric preparation process, the first inspection process, and the first cutting process is preferably a continuous production line. In the series of manufacturing steps described above, the cut first polarizing plate to be bonded to one surface of the optical display unit W is formed. Below, the process of forming the cut | disconnected 2nd polarizing plate for bonding on the other surface of the optical display unit W is demonstrated. In addition, the process of forming each of the cut first polarizing plate and the second polarizing plate is performed in parallel.

  (5) 2nd roll original fabric preparation process (FIG. 1, S11). The 2nd roll original fabric formed by winding a beltlike 2nd sheet product in roll shape is prepared. The width | variety of a 2nd roll original fabric is dependent on the bonding size of the optical display unit W, for example, is formed in the width | variety different from a 1st roll original fabric.

  (6) Transport process (FIG. 1, S12: second transport step). The second sheet material 40 is fed out from the prepared and installed second roll, and conveyed downstream.

  (7) Second inspection step (FIG. 1, S13). The second sheet product 40 is inspected for defects using the second defect inspection device 24. The defect inspection method here is the same as the method using the first defect inspection apparatus 14 described above. However, the first inspection step (S3) and the second inspection step (S13) can be omitted. In this case, the defect inspection of the first sheet product 30 and the second sheet product 40 is performed at the stage of manufacturing the first roll original fabric and the second roll original fabric, and the first roll original fabric subjected to the defect inspection in advance. And the structure that an optical display apparatus is manufactured using a 2nd roll original fabric may be sufficient.

  (8) Second cutting step (FIG. 1, S14: second cutting step). The 1st cutting device 26 does not cut | disconnect a 2nd release film, The 2nd polarizing plate with which the said 2nd release film was bonded together, The surface protection film bonded with the 2nd polarizing plate, Is cut into a predetermined size. At this time, the pressure-sensitive adhesive layer formed between the second release film and the second polarizing plate may or may not be cut. Examples of the cutting means include a laser device, a cutter, and other known cutting means. Based on the defect information obtained by the second defect inspection apparatus 24, it is preferable to be configured to cut so as to avoid the defect. Thereby, the yield of the 2nd sheet product 40 improves significantly. The second sheet product 40 including the defects is excluded by a second rejection device (not shown) and is not attached to the optical display unit W.

  In parallel with the step of forming the cut first polarizing plate and the second polarizing plate as described above, a step of transporting the optical display unit W is performed. The optical display unit W is subjected to the following processing during its conveyance.

  (9) Cleaning step (FIG. 1, S6). The surface of the optical display unit W is cleaned by polishing cleaning, water cleaning, or the like.

  (10) 1st polarizing plate bonding process (FIG. 1, S5: 1st bonding step). After the first release film is removed, the cut first polarizing plate is bonded to one surface of the optical display unit W by the first bonding device 18 via the pressure-sensitive adhesive layer. At the time of bonding, the first polarizing plate and the optical display unit W are sandwiched between a pair of rolls and are bonded. In addition, in this 1st polarizing plate bonding process and the 2nd polarizing plate bonding process mentioned later, after aligning so that a 1st polarizing plate and a 2nd polarizing plate may each convey a predetermined position, respectively. Are bonded to the optical display unit W. However, the alignment of the polarizing plate is not limited to the configuration performed after the first cutting step and the second cutting step, but is performed before or in parallel with the first cutting step and the second cutting step. Such a configuration may be adopted.

  (11) 2nd polarizing plate bonding process (FIG. 1, S15: 2nd bonding step). The cut | disconnected 2nd polarizing plate is bonded by the 2nd bonding apparatus 28 to the other surface of the optical display unit W through an adhesive layer, after a 2nd release film is removed. At the time of bonding, the second polarizing plate and the optical display unit W are sandwiched between a pair of rolls and bonded. Before the second polarizing plate is bonded to the optical display unit W, the optical display unit after the first polarizing plate is bonded so that the first polarizing plate and the second polarizing plate are in a crossed Nicols relationship. W is rotated 90 degrees by the turning mechanism 20. However, the configuration is not limited to the configuration in which the optical display unit W is rotated by 90 degrees, but the first polarized light is not limited to the configuration in which the first sheet product 30 and the second sheet product 40 are conveyed in directions orthogonal to each other. The plate and the second polarizing plate can be in a crossed Nicols relationship.

  (12) Optical display unit inspection process (FIG. 1, S16). The inspection device inspects the optical display unit W in which the polarizing plate is attached to both surfaces. Examples of the inspection method include a method of taking an image and processing an image using transmitted light and reflected light on both surfaces of the optical display unit W. As another method, a method of installing a polarizing film for inspection between the CCD camera and the inspection object is also exemplified. Note that a known method can be applied to the image processing algorithm, and for example, a defect can be detected by density determination by binarization processing.

  (13) Non-defective product determination of the optical display unit W is performed based on the defect information obtained by the inspection apparatus. The optical display unit W determined to be non-defective is conveyed to the next mounting process. If a defective product is determined, a rework process is performed, a new polarizing plate is applied, and then inspected. If a non-defective product is determined, the process proceeds to a mounting process. Discarded.

  In the above series of manufacturing steps, the optical display device can be suitably manufactured by making the first polarizing plate bonding step and the second polarizing plate bonding step a continuous production line.

  In the first and second cutting steps, a method (half-cut method) for cutting other members of the sheet product without cutting the release film has been described. According to such a configuration, without cutting the release film bonded to the polarizing plate via the pressure-sensitive adhesive layer, the polarizing plate and the pressure-sensitive adhesive layer are cut, and the optical display unit W is bonded. Before, a release film can be peeled from a polarizing plate. That is, since the pressure-sensitive adhesive layer, which is the bonding surface of the polarizing plate, can be configured not to be exposed until just before the bonding, foreign matters can be prevented from being mixed into the bonding surface of the polarizing plate.

  In particular, by cutting the polarizing plate and the pressure-sensitive adhesive layer without cutting the release film, the cut polarizing plate and the pressure-sensitive adhesive layer can be transported using the release film as a carrier. Therefore, since the polarizing plate transport device can be made simpler, the manufacturing cost of the optical display device can be further reduced. However, the present invention can be applied not only to the half-cut mode in which the sheet product fed from the roll raw material is cut while leaving the release film, but also in the full-cut mode to cut with the release film. it can.

(Composition of sheet product)
FIG. 3 is a cross-sectional view showing a configuration example of the first sheet product 30 and the second sheet product 40. In the present embodiment, the first sheet product 30 and the second sheet product 40 are formed by laminating films in the same manner, and the surface protective film 31, the polarizing plate 32, and the release film 33 are laminated, respectively. Is formed. The surface protective film 31 is bonded to one surface of the polarizing plate 32 via an adhesive layer 34, and the release film 33 is bonded to the other surface of the polarizing plate 32 via an adhesive layer 35. It has been. However, the surface protective film 31 and the pressure-sensitive adhesive layer 34 can be omitted. Further, the first sheet product 30 and the second sheet product 40 are not limited to those in which films are laminated in the same manner, but may be those in which films are laminated in different manners. For example, a combination in which a retardation layer is formed on only one of the first sheet product 30 and the second sheet product 40 may be used.

  In the example of FIG. 3, the polarizing plate 32 includes a polarizing film 36, a polarizer protective film 37, and a coat layer 38, and the polarizer protective film 37 is bonded to one surface of the polarizing film 36 through an adhesive layer 39. In addition, a coat layer 38 is formed on the other surface of the polarizing film 36. The coat layer 38 may be omitted. The surface protective film 31 is bonded to the surface of the polarizer protective film 37 opposite to the adhesive layer 39 via the pressure-sensitive adhesive layer 34. A release film 33 is bonded to the surface of the coat layer 38 opposite to the polarizing film 36 with an adhesive layer 35 interposed therebetween. At the time of bonding to the optical display unit W, the release film 33 is peeled off, whereby the pressure-sensitive adhesive layer 35 formed on the release film 33 is transferred to the polarizing plate 32 side. Is attached to the optical display unit W.

  The polarizing film 36 is made of a film-like polarizer (polyvinyl alcohol film), and can be obtained, for example, by drying a polyvinyl alcohol (PVA) film that has been subjected to dyeing / crosslinking and stretching. The thickness of the polarizing film 36 is preferably 20 to 300 μm, more preferably 30 to 150 μm.

  The coating layer 38 is formed on the surface of the polarizing film 36 opposite to the polarizer protective film 37 from the viewpoint of adhesion with the pressure-sensitive adhesive layer 35 and protection of the polarizer. The coat layer 38 is not particularly limited, but is preferably an adhesive mainly composed of polyvinyl alcohol, isocyanate, cyan acrylate, aziridine and the like from the viewpoint of adhesion. The thickness of the coating layer 38 at that time is preferably 0.01 to 10 μm, and more preferably 0.1 to 7 μm. From the viewpoint of protecting the polarizer, for example, a material mainly composed of an epoxy resin, an oxetane resin, or a urethane resin is preferable. The thickness of the coat layer 38 at that time is preferably 1 to 30 μm, and more preferably 10 to 20 μm.

  The polarizer protective film 37 is made of, for example, a TAC (triacetyl cellulose) film, a PET (polyethylene terephthalate) film, or the like. Although the thickness of the polarizer protective film 37 can be determined as appropriate, it is generally preferably 10 to 250 μm from the viewpoint of workability such as strength and handleability, and thin layer properties, and is 20 to 100 μm. More preferred.

  The surface protective film 31 is intended to prevent scratches and contamination of the polarizing plate 32. As the surface protective film 31, for example, a suitable thin leaf body such as a plastic film, rubber sheet, paper, cloth, non-woven fabric, net, foamed sheet, metal foil, laminate thereof, or the like, silicone type or long chain alkyl type In addition, an appropriate one according to the prior art, such as one coated with an appropriate release agent such as fluorine-based or molybdenum sulfide, can be used.

  As with the surface protective film 31, the release film 33 is made of, for example, a suitable thin leaf such as a plastic film, rubber sheet, paper, cloth, non-woven fabric, net, foamed sheet, metal foil, or a laminate thereof as necessary. Appropriate ones according to the prior art such as those coated with an appropriate release agent such as silicone-based, long-chain alkyl-based, fluorine-based or molybdenum sulfide can be used. The release film 33 is formed with an adhesive layer 35 made of a strong adhesive having a higher adhesive strength than the adhesive layer 34 formed on the surface protective film 31.

  The configuration of the polarizing plate 32 is not limited to the polarizing film 36, the polarizer protective film 37, and the coat layer 38, but other layers (films) that can impart optical functions such as a retardation film and a brightness enhancement film are laminated. It may be a configuration.

  In the example shown in FIG. 3, the polarizing plate 32 has a polarizer protective film 37 only on one side, and the release film 33 is bonded to the surface opposite to the polarizer protective film 37 via an adhesive layer 35. Since this is a single-sided protection type and the front and back configurations are asymmetric, it has the property of warping toward the release film 33 as shown in FIG.

  In the present embodiment, the first roll original fabric and the second roll original fabric are formed by winding the sheet products 30 and 40 as described above with the release film 33 side inward (roll original). Anti-manufacturing step). More specifically, the first roll original fabric and the second roll original fabric are manufactured by winding the sheet products 30 and 40 around a core having a predetermined diameter with a predetermined tension.

  The outer diameter of the core is 70 mm or more, more preferably 150 mm or more. If the outer diameter of the winding core is too small, the curvature increases, so that problems such as floating of the release film 33 and warping toward the release film 33 side make bonding difficult. Work problems may occur. On the other hand, since there is an upper limit for the outer diameter of the roll after being wound, if the outer diameter of the core is too large, the length of the sheet products 30 and 40 that can be wound around the core is shortened. Therefore, the outer diameter of the core is preferably the above value.

  The outer diameter (winding diameter) of the roll raw material after winding the sheet products 30 and 40 is 1500 mm or less, more preferably 1000 mm or less. If the winding diameter is too large, the curvature of the outermost peripheral portion of the sheet product 30, 40 becomes small, and when it is rewound, it cannot be satisfactorily held in a state of warping on the release film 33 side. The above values are preferred.

  The tension (winding tension) applied to the sheet products 30 and 40 when wound around the core is 50 N / m or more, and more preferably 100 N / m or more. If the tension is too small, it cannot be wound well around the core, and cannot be held well in a state of being warped toward the release film 33 when the sheet products 30 and 40 are rewound. Therefore, the tension is preferably the above value.

  In the present embodiment, the single-side protection type polarizing plate 32 having a property of warping toward the release film 33 side is wound with the release film 33 side inward, so that the mold is released when it is rewound. It can hold | maintain favorably in the state which curved to the film 33 side. This prevents the polarizing plate 32 from being peeled off from the bonding surface of the optical display unit W in a state where the polarizing plate 32 fed out from the raw roll is cut to a predetermined size and bonded to the optical display unit W. Can do. Therefore, peeling of the polarizing plate 32 from the optical display unit W can be effectively prevented with a simple configuration in which the polarizing plate 32 is wound with the release film 33 side inward.

  Moreover, since the polarizing plate 32 is wound with the pressure-sensitive adhesive layer 35 side inside, it is possible to prevent the pressure-sensitive adhesive dents (surface scratches). Thereby, it is possible to prevent air bubbles from being mixed at the time of bonding due to the dents of the adhesive, and it is possible to omit a process such as autoclave for eliminating the air bubbles.

  When the polarizing plate 32 is unwound from the roll material as described above and bonded to the optical display unit W, it is preferable to bond the polarizing plate 32 while applying a predetermined tension, but it is limited to such a configuration. However, the present invention can also be applied to a configuration in which bonding is performed without applying tension. When a predetermined tension is applied to the polarizing plate 32, the polarizing plate 32 that is warped toward the release film 33 can be bonded to the optical display unit W in a state where the polarizing plate 32 extends straight. Thereby, the precision of the bonding position of the polarizing plate 32 with respect to the optical display unit W can be improved.

  In the present embodiment, the polarizing plate 32 and the pressure-sensitive adhesive layer 35 are cut without cutting the release film 33 bonded to the polarizing plate 32 via the pressure-sensitive adhesive layer 35, and the optical display unit W is cut. Before the bonding process, a half-cut method in which the release film 33 is peeled off from the polarizing plate 32 is adopted, but the polarizing plate 32 is wound with the release film 33 side inside as described above. Thus, it is possible to prevent the polarizing plate 32 from being peeled off from the release film 33 during conveyance. That is, when the polarizing plate 32 is rewound, it is held well in a state of being warped toward the release film 33, so that even when the polarizing plate 32 passes through the transport roller, the half-cut polarizing plate It can prevent that the edge part of 32 peels from the release film 33. FIG.

Below, the test result performed by bonding several types of polarizing plates to a glass plate, respectively, and confirming the dispersion | variation in the bonding position at that time and the presence or absence of end surface peeling is demonstrated. In this test, a sample of an A4 size polarizing plate was attached to a glass plate larger than that, and then the variation in the bonding position and the presence or absence of end face peeling were confirmed. About the dispersion | variation in the bonding position, it measured by calculating 3 (sigma) ((sigma) is a standard deviation of a measured value) in N = 10. On the other hand, regarding the presence or absence of end face peeling, after leaving in each environment of high temperature standard humidity atmosphere (60 ° C.) and high temperature high humidity atmosphere (60 ° C./95% RH) for 1000 hours, take out and observe peeling of the end face. It was determined by judging that there was peeling only when there was peeling exceeding 0.5 mm. The test results are as shown in Tables 1 and 2 below.

Example 1
In Example 1, a single-sided protective type polarizing plate in which a polarizer protective film is bonded only to one side of a polarizing film is cut out from a roll that is formed by being wound with the release film side inside. Then, the polarizing plate was bonded to the optical display unit while applying a tension of 50 N / m to the polarizing plate. The amount of warpage of the polarizing plate toward the release film when it was cut out was 80 mm. In Example 1, the bonding position variation was very small, about ± 1 mm. Moreover, about end surface peeling, peeling was not confirmed in any environment.

(Example 2)
In Example 2, a single-sided protective type polarizing plate in which a polarizer protective film is bonded only to one side of a polarizing film is cut out from a roll original formed by being wound with the release film side inward. Then, the polarizing plate was bonded to the optical display unit while applying a tension of 350 N / m to the polarizing plate. The amount of warpage of the polarizing plate toward the release film when it was cut out was 80 mm. In Example 2, the variation in the bonding position was very small, about ± 1 mm. Moreover, about end surface peeling, peeling was not confirmed in any environment.

(Example 3)
In Example 3, a single-sided protective type polarizing plate in which a polarizer protective film is bonded only to one side of a polarizing film is cut out from a roll that is formed by being wound with the release film side inside. Then, the polarizing plate was bonded to the optical display unit while applying a tension of 500 N / m to the polarizing plate. The amount of warpage of the polarizing plate toward the release film when it was cut out was 80 mm. In Example 3, the variation in bonding position was very small, about ± 1 mm. Moreover, about end surface peeling, peeling was not confirmed in any environment.

Example 4
In Example 4, a single-sided protection type polarizing plate in which a polarizer protective film is bonded only to one side of a polarizing film is cut out from a roll raw material formed by being wound with the release film side inside. Then, the polarizing plate was bonded to the optical display unit while applying a tension of 30 N / m to the polarizing plate. The amount of warpage of the polarizing plate toward the release film when it was cut out was 80 mm. In Example 4, the variation in bonding position was small, about ± 2 mm. Moreover, about end surface peeling, peeling was not confirmed in any environment.

(Comparative Example 1)
In Comparative Example 1, a single-sided protective type polarizing plate in which a polarizer protective film is bonded only to one side of a polarizing film is cut out from a roll that is formed by being wound with the release film side facing outward. Then, the polarizing plate was bonded to the optical display unit while applying a tension of 350 N / m to the polarizing plate. The amount of warpage of the polarizing plate toward the release film when it was cut out was 20 mm. In this comparative example 1, with respect to end face peeling, peeling was confirmed in any environment.

(Comparative Example 2)
In Comparative Example 2, a double-sided protective type polarizing plate in which a polarizer protective film is bonded to both sides of a polarizing film is cut out from a roll raw material formed by being wound with the release film side inside. The polarizing plate was bonded to the optical display unit while applying a tension of 350 N / m. The amount of warpage of the polarizing plate toward the release film when it was cut out was 10 mm. In this comparative example 2, with respect to the end face peeling, peeling was confirmed in any environment.

  In addition, as a reference example, a single-side protection type polarizing plate in which a polarizer protective film is bonded only to one side of a polarizing film from a roll original formed by being wound with the release film side inside. Cut out and bonded to the optical display unit while applying a tension of 600 N / m to the polarizing plate. In this case, the polarizing plate was broken.

  According to the above test results, from the viewpoint of end face peeling, it is preferable to use a single-side protection type polarizing plate rather than a double-side protection type, and the single-side protection type polarizing plate is wound with the release film side inward. The direction of rotation is more preferable than the case of winding with the release film side outside. Moreover, if the tension | tensile_strength provided to a polarizing plate in the case of bonding to an optical display unit is 30-500 N / m, the precision of the bonding position of the polarizing plate with respect to an optical display unit can be improved more, The said If tension | tensile_strength is 50-500 N / m, the precision of the bonding position of the polarizing plate with respect to an optical display unit can further be improved.

DESCRIPTION OF SYMBOLS 31 Surface protective film 32 Polarizing plate 33 Release film 34 Adhesive layer 35 Adhesive layer 36 Polarizing film 37 Polarizer protective film 38 Coat layer 39 Adhesive layer

Claims (3)

An optical display device manufacturing method for manufacturing an optical display device by bonding a polarizing plate to an optical display unit,
A polarizing plate having a polarizer protective film on one side is wound with the release film side bonded to the surface opposite to the polarizer protective film with respect to the polarizing plate via an adhesive layer inside. From the roll raw material formed by being carried, the conveying step of paying out the polarizing plate and the release film,
The cutting step of cutting the polarizing plate fed from the roll raw fabric together with the release film, or cutting into a predetermined size leaving the release film,
An optical display device manufacturing method comprising: a bonding step of bonding the polarizing plate to the optical display unit.   The optical display device manufacturing method according to claim 1, wherein in the bonding step, the optical display unit is bonded while applying a predetermined tension to the polarizing plate. Formed by winding a polarizing plate, an optical display device manufacturing roll for cutting and bonding the polarizing plate to a predetermined size for an optical display unit,
A polarizing plate having a polarizer protective film on one side is wound with the release film side bonded to the surface opposite to the polarizer protective film with respect to the polarizing plate via an adhesive layer inside. A roll for manufacturing an optical display device, characterized in that it is formed by being processed.

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