TWI782918B - Polarizing plate manufacturing method and manufacturing device thereof - Google Patents

Abstract

[Problem] The present invention is concerned with providing a manufacturing method of a special-shaped polarizing plate and a manufacturing apparatus thereof, especially a manufacturing method of a special-shaped polarizing plate having a small-diameter concave R portion and/or a hole portion, and the manufacturing method of the special-shaped polarizing plate The production device thereof suppresses cracks, breakage, and discoloration that occur during processing. [Solution] A method of manufacturing a special-shaped polarizing plate, which is a method of manufacturing a special-shaped polarizing plate with a concave R portion, and includes the step of forming the aforementioned concave R portion by using a cutting mechanism. The cutting mechanism is to allow the blade to cut from the lateral direction contact and cut.

Description

Polarizing plate manufacturing method and manufacturing device thereof

Field of the Invention The present invention relates to a method for manufacturing a special-shaped polarizing plate and a manufacturing device thereof. More specifically, it relates to a manufacturing method and a manufacturing device of a special-shaped polarizing plate having concave R portions and/or hole portions. Also, the present invention relates to an optical film using the special-shaped polarizing plate. Furthermore, it relates to an image display device such as a liquid crystal display device, an organic EL display device, and a PDP using the special-shaped polarizing plate and the optical film.

Background of the Invention In recent years, the use of polarizing plates has been expected to be used in instrument displays of automobiles, smart watches, and the like. In addition, from the viewpoint of the design of smart watches, the use of polarizers in shapes other than rectangles, or the use of polarizers with through holes are increasingly desired. Furthermore, in these forms of special-shaped processing, the pursuit of more delicate and delicate processing and more complex processing that has never been seen before is increasing, and small-diameter concave R processing or small-diameter drilling is implemented. processing situation.

In order to process a polarizing plate into a different shape, a punching process which forms a different-shaped die and punches out a polarizing plate, and a cutting process which uses laser irradiation are mentioned, for example. However, in the former punching process, it has been found that there is a problem that cracks and breaks are generated on the polarizing plate due to damage to the cutting of the polarizing plate. Also, in the latter laser processing, the problem of discoloration of the polarizing plate due to heat has been known. Among them, it has been found out in the studies of the patent applicants that cracks and breaks tend to occur in the concave processed parts such as small-diameter drilling or small-diameter concave R processing.

In addition, proposals concerning trimming processing of the end faces of polarizing plates have been made heretofore (see, for example, Patent Documents 1 and 2). However, any of the above-mentioned proposals is only a proposal related to the trimming process of the end portion of the cutting hole after cutting the polarizing plate into a rectangle, and is not a technique for performing concave processing on the polarizing plate itself. Also, in the above-mentioned proposals, there is no disclosure regarding the problems of cracks and breakages when the polarizing plate is subjected to fine concave processing. Prior Art Documents Patent Documents

Patent Document 1: Japanese Patent Laid-Open No. 2004-148461 Patent Document 2: Japanese Patent Laid-Open No. 2004-148419

Summary of the Invention Problems to be Solved by the Invention The object of the present invention is to provide a manufacturing method and apparatus for a special-shaped polarizing plate, especially a special-shaped polarizing plate having a small-diameter concave R portion and/or hole portion, in contrast to such matters. The manufacturing method, the manufacturing method of the special-shaped polarizing plate and the manufacturing device thereof suppress cracks, breakage, and discoloration generated on the special-shaped polarizing plate during processing. means to solve problems

As a result of earnest research to solve the above-mentioned problems, the inventors of the present application found that the above-mentioned object can be achieved by the manufacturing method shown below, etc., and finally completed the present invention.

The method for manufacturing a special-shaped polarizing plate of the present invention is a method for manufacturing a special-shaped polarizing plate with a concave R portion, which is characterized in that it includes the step of forming the above-mentioned concave R portion by using a cutting mechanism. The cutting surfaces abut and cut.

The manufacturing method of the special-shaped polarizing plate of the present invention particularly utilizes a mechanism that allows the blade to abut against the cutting surface of the polarizing plate from the lateral direction, thereby suppressing cracks, The occurrence of breakage and discoloration make it possible to manufacture special-shaped polarizing plates with small-diameter concave R portions.

In addition, in the present invention, the concave R portion refers to a portion having a concave portion and a curved portion, and a curved portion including a corner portion of the concave portion having a circular shape, an elliptical shape, a substantially circular shape, or the like. Also, the convex R portion refers to a portion having a convex portion and a curved portion, and a portion including a curved portion such as a circular, elliptical, or substantially circular shape including a corner portion of the convex portion. Examples thereof include a concave R portion or a convex R portion as shown in FIG. 1 .

In addition, in the method for manufacturing a special-shaped polarizing plate of the present invention, the radius of the concave R portion is preferably 5 mm or less. By using the above-mentioned manufacturing method, even when the radius of the concave R portion is 5 mm or less, the occurrence of cracks, breakage, and discoloration during the processing of the polarizing plate is suppressed, and the radius of the concave R portion is made to be For example, the manufacture of special-shaped polarizing plates with a concave R portion with a small radius of 5 mm or less becomes feasible. In addition, the above-mentioned concave R portion is defined as: when the R portion is a circle, it refers to the radius of the circle, and when the R portion is a non-circular shape such as an ellipse or a substantially circular shape, it means refers to its radius of curvature.

In addition, in the method for manufacturing a special-shaped polarizing plate of the present invention, the above-mentioned cutting mechanism is preferably an end mill. By utilizing the above-mentioned manufacturing method, it is especially suitable when performing small-diameter concave R processing.

In addition, in the method for manufacturing a special-shaped polarizing plate of the present invention, the cutting angle between the machining direction and the blade surface of the blade is preferably 60° or more. By using the above manufacturing method, it becomes possible to suppress the occurrence of delamination of the irregularly shaped polarizing plate.

In addition, the manufacturing device of the irregularly shaped polarizing plate of the present invention is a manufacturing device of the irregularly shaped polarizing plate having the concave R portion, and is characterized in that it includes a cutting mechanism that makes the cutting edge abut against the cutting surface from the lateral direction and cuts.

By using the above-mentioned manufacturing apparatus, it is possible to suppress the occurrence of cracks, breakage, and discoloration during processing of the polarizing plate, and it is possible to easily manufacture a special-shaped polarizing plate having a small-diameter concave R portion in particular.

In addition, in the manufacturing apparatus of the irregularly shaped polarizing plate of the present invention, the radius of the above-mentioned concave R portion is preferably 5 mm or less. By using the above-mentioned manufacturing apparatus, even when the radius of the concave R portion is 5 mm or less, the generation of cracks, breakage, and discoloration during the processing of the polarizing plate can be suppressed, and the production of the concave R portion can be easily performed. Manufacture of special-shaped polarizing plates with a concave R portion whose radius is as small as 5mm or less.

Moreover, in the manufacturing device of the special-shaped polarizing plate of the present invention, the above-mentioned cutting mechanism is preferably an end mill. By utilizing the above-mentioned manufacturing apparatus, it is especially suitable when performing small-diameter concave R processing.

Moreover, in the manufacturing apparatus of the irregular-shaped polarizing plate of the present invention, the cutting angle formed by the processing direction by the cutting mechanism and the cutting edge surface of the cutting edge is preferably 60° or more. By utilizing the above-mentioned manufacturing apparatus, it becomes possible to suppress the occurrence of delamination of the irregularly-shaped polarizing plate.

Furthermore, the method for manufacturing a special-shaped polarizing plate of the present invention is a method for manufacturing a special-shaped polarizing plate having a hole, and is characterized in that it includes the step of forming the hole with an end mill.

In the above-mentioned manufacturing method, the mechanism that makes the blade abut against the cutting surface of the polarizing plate from the lateral direction is used, thereby suppressing the occurrence of cracks, breakage, And discoloration, making it possible to manufacture special-shaped polarizing plates with small-diameter holes.

In addition, in the present invention, a hole portion refers to a portion having a hole such as a circular shape, an elliptical shape, a substantially circular shape, or an angular shape, and refers to a portion penetrating through a polarizing plate. For example, the hole part shown in FIG. 1 etc. are mentioned.

In addition, in the above-mentioned method of manufacturing a special-shaped polarizing plate, it is preferable that the radius of the above-mentioned hole is 5 mm or less. By using the above-mentioned manufacturing method, even when the radius of the hole is 5 mm or less, the generation of cracks, breakage, and discoloration during the processing of the polarizing plate are suppressed, and the radius of the hole is, for example, 5 mm. Manufacturing of the following special-shaped polarizing plates with micro-radius holes becomes possible. In addition, the radius of the above-mentioned hole is set: when the hole is circular, it means the radius of the circle, and when the hole is not circular, such as an ellipse or a substantially circular shape, is its radius of curvature.

In addition, in the above method of manufacturing a special-shaped polarizing plate, the cutting angle between the machining direction and the blade surface of the end mill is preferably 60° or more. By utilizing the above-mentioned manufacturing method, it becomes possible to suppress the occurrence of delamination of the irregularly-shaped polarizing plate.

Moreover, the manufacturing apparatus of the irregular-shaped polarizing plate of this invention is the manufacturing apparatus of the irregular-shaped polarizing plate which has a hole part, It is characterized in that it is provided with the end mill.

By using the above manufacturing apparatus, it is possible to suppress the occurrence of cracks, breakage, and discoloration during processing of the polarizing plate, and it is possible to easily manufacture a special-shaped polarizing plate having a small-diameter hole.

In addition, in the manufacturing apparatus of the special-shaped polarizing plate of the present invention, it is preferable that the radius of the above-mentioned hole is 5 mm or less. By using the above-mentioned manufacturing apparatus, even when the radius of the hole is 5 mm or less, the generation of cracks, breakage, and discoloration during the processing of the polarizing plate can be suppressed, and the radius of the hole can be easily obtained. It is the manufacture of special-shaped polarizing plates with small-radius holes such as 5mm or less.

In addition, in the manufacturing apparatus of the special-shaped polarizing plate of the present invention, the cutting angle formed by the processing direction and the blade surface of the above-mentioned end mill is preferably 60° or more. By utilizing the above-mentioned manufacturing apparatus, it becomes possible to suppress the occurrence of delamination of the irregularly-shaped polarizing plate.

Embodiments for Carrying Out the Invention Hereinafter, embodiments of the present invention will be described.

The method for manufacturing a special-shaped polarizing plate of the present invention is a method for manufacturing a special-shaped polarizing plate with a concave R portion, which is characterized in that it includes the step of forming the above-mentioned concave R portion by using a cutting mechanism. The cutting surfaces abut and cut.

Furthermore, the method for manufacturing a special-shaped polarizing plate of the present invention is a method for manufacturing a special-shaped polarizing plate having a hole, and is characterized in that it includes the step of forming the hole with an end mill.

The method of manufacturing a special-shaped polarizing plate of the present invention is characterized in that it includes the step of forming the above-mentioned concave R portion and/or hole portion by using a cutting mechanism that makes a cutting edge abut against the cutting surface from the lateral direction and cuts. In particular, the mechanism that allows the blade to abut against the cutting surface of the polarizing plate from the lateral direction is used to suppress the occurrence of cracks, breakage, and discoloration that have been difficult to suppress in the processing of the polarizing plate before, so that especially It is possible to manufacture a special-shaped polarizing plate having a small-diameter concave R portion and/or hole portion. Also, the cutting mechanism that allows the blade to abut against the cutting surface from the lateral direction and cut, for example, can be exemplified by planing (scraping the processing surface in parallel by having a protruding tool with a rotation axis parallel to the processing surface) Processing), end mill processing, etc. and the method. In the manufacturing method of the special-shaped polarizing plate of the present invention, the above-mentioned cutting mechanism is an end mill, which is especially ideal in the case of small-diameter concave R processing and small-diameter hole processing. Moreover, especially in the manufacturing method of the irregular-shaped polarizing plate which has a hole part, an end mill is used as the said cutting means.

Note that an end mill is a type of cutting tool, and unlike a drill that performs machining only in the axial direction (for drilling), it can also perform machining in a direction perpendicular to the rotation axis.

Hereinafter, an embodiment in which machining is performed using an end mill will be described using FIG. 2 as an example. For the polarizing plate of the object to form the concave R portion and/or the hole portion, the blade portion of the end mill corresponding to the blade in this case is rotated, and the cutting surface of the polarizing plate is abutted against from the lateral direction and For cutting. Then, it is moved in the processing direction together with the rotation of the blade portion of the end mill, and the cutting process of the polarizing plate is continued to process a predetermined irregular-shaped polarizing plate.

In the case of the above-mentioned end mill, the rotation of the blade portion for cutting is, for example, as shown in FIG. ) rotation, and the rotation may be performed continuously, in stages, or intermittently, while the cutting of the polarizing plate by the end mill is performed in the processing direction. At this time, the cutting edge portion of the end mill is cutting in a state of being in contact with the cutting surface from the lateral direction. Furthermore, in the conventional punching process of punching with a knife die, etc., the cutting edge is formed from the upper part of the surface of the polarizing plate (a direction parallel to the cutting surface in FIG. 2 and perpendicular to the surface of the polarizing plate) direction) contact and cut off.

Also, when planing is used as the above-mentioned cutting mechanism, the end mill shown in FIG. 2 may be replaced, and the planing blade may be brought into contact with the cutting surface from the lateral direction to perform cutting.

Also, for example, when drilling a hole, not only directly use an end mill or the like to drill the hole, but also additionally or additionally use an end mill or the like for the hole previously opened by other punching or the like. End face cutting to enlarge the hole, etc., to make a hole of the desired shape.

Also, by using the method for manufacturing a special-shaped polarizing plate of the present invention, even when the above-mentioned concave R portion is small in diameter or finer, it is possible to suppress the occurrence of cracks, breakage, and discoloration that occur during processing. , suitably carry out manufacturing and processing.

Therefore, in the manufacturing method of the irregular-shaped polarizing plate of the present invention, even if the radius of the above-mentioned concave R portion is 5 mm or less, for example, the manufacturing process can be easily performed. In addition, for example, the above-mentioned radius may be 1 mm to 5 mm, or 1 mm to 4 mm, or 2 mm to 3 mm. By using the above-mentioned manufacturing method, even when the radius of the concave R portion is 5 mm or less, the occurrence of cracks, breakage, and discoloration during the processing of the polarizing plate is suppressed, and the radius of the concave R portion is made to be For example, the manufacture of special-shaped polarizing plates with a concave R portion with a small radius of 5 mm or less becomes feasible.

Therefore, in the manufacturing method of the irregular-shaped polarizing plate of this invention, even if the radius of the said hole part is 5 mm or less, manufacturing process can be performed easily. In addition, for example, the above-mentioned radius may be 1 mm to 5 mm, or 1 mm to 4 mm, or 2 mm to 3 mm. By using the above-mentioned manufacturing method, even when the radius of the hole is 5 mm or less, the generation of cracks, breakage, and discoloration during the processing of the polarizing plate are suppressed, and the radius of the hole is, for example, 5 mm. Manufacturing of the following special-shaped polarizing plates with micro-radius holes becomes possible.

In addition, in the method for manufacturing a special-shaped polarizing plate of the present invention, the cutting angle between the machining direction and the blade surface of the blade is preferably 60° or more. The above-mentioned cutting angle is preferably 60°-90°, and may be 65°-90°, or 70°-85°, or 70°-80°. By utilizing the above-mentioned manufacturing method, it becomes possible to suppress the occurrence of delamination of the irregularly-shaped polarizing plate.

Furthermore, in the present invention, the cutting angle refers to the cutting angle formed by the machining direction by the cutting mechanism and the cutting edge surface of the blade, and an example of machining with an end mill is shown in FIG. 3 . The angle formed by the direction of the rotation axis of the end mill and the cutting edge is called the helix angle. When machining is performed so that the direction of the rotation axis of the end mill is perpendicular to the machining direction as shown in Fig. 3, the angle from 90 °The cutting angle is obtained by subtracting the helix angle of the end mill blade.

In addition, the manufacturing device of the irregularly shaped polarizing plate of the present invention is a manufacturing device of the irregularly shaped polarizing plate having the concave R portion, and is characterized in that it includes a cutting mechanism that makes the cutting edge abut against the cutting surface from the lateral direction and cuts.

In the manufacturing device of the special-shaped polarizing plate having the concave R portion of the present invention, the cutting mechanism including the end mill, which makes the cutting edge abut against the above-mentioned cutting surface from the lateral direction and cuts, can be installed in an appropriate device by a known method. superior.

Moreover, in the manufacturing apparatus of the irregular-shaped polarizing plate of this invention, even if the radius of the said concave R part is 5 mm or less, manufacturing process becomes easy. In addition, for example, the above-mentioned radius may be 1 mm to 5 mm, or 1 mm to 4 mm, or 2 mm to 3 mm. By using the above-mentioned manufacturing method, even when the radius of the concave R portion is 5 mm or less, the occurrence of cracks, breakage, and discoloration during the processing of the polarizing plate is suppressed, and the radius of the concave R portion is made to be For example, the manufacture of special-shaped polarizing plates with a concave R portion with a small radius of 5 mm or less becomes feasible.

In addition, in the manufacturing apparatus of the special-shaped polarizing plate of the present invention, the cutting angle formed by the processing direction by the cutting mechanism and the cutting edge surface of the cutting edge is preferably 60° or more. The above-mentioned cutting angle is preferably 60°-90°, and may be 65°-90°, or 70°-85°, or 70°-80°. By utilizing the above-mentioned manufacturing apparatus, it becomes possible to suppress the occurrence of delamination of the irregularly-shaped polarizing plate.

Moreover, the manufacturing apparatus of the irregular-shaped polarizing plate of this invention is the manufacturing apparatus of the irregular-shaped polarizing plate which has a hole part, It is characterized in that it is provided with the end mill.

Moreover, in the manufacturing apparatus of the irregular-shaped polarizing plate which has a hole part of this invention, the above-mentioned end milling cutter can be installed in an appropriate apparatus by a well-known method.

Moreover, in the manufacturing apparatus of the irregular-shaped polarizing plate of this invention, even if the radius of the said hole part is 5 mm or less, manufacturing process becomes easy. In addition, for example, the above-mentioned radius may be 1 mm to 5 mm, or 1 mm to 4 mm, or 2 mm to 3 mm. By using the above-mentioned manufacturing method, even when the radius of the hole is 5 mm or less, the generation of cracks, breakage, and discoloration during the processing of the polarizing plate are suppressed, and the radius of the hole is, for example, 5 mm. Manufacturing of the following special-shaped polarizing plates with micro-radius holes becomes possible.

In addition, in the manufacturing apparatus of the special-shaped polarizing plate of the present invention, the cutting angle formed by the processing direction by the cutting mechanism and the cutting edge surface of the cutting edge is preferably 60° or more. The above-mentioned cutting angle is preferably 60°-90°, and may be 65°-90°, or 70°-85°, or 70°-80°. By utilizing the above-mentioned manufacturing apparatus, it becomes possible to suppress the occurrence of delamination of the irregularly-shaped polarizing plate.

In addition, as the above-mentioned end mill, for example, the end mill described in FIGS. 4 and 5 can also be suitably used. Furthermore, what is shown in FIG. 5 is the example where the number of blades is 2 pieces, 3 pieces, 4 pieces, or 6 pieces.

As the shape of the end mill, the number of blades should be set to 1 to 6 pieces, and the number of blades can be set to 1 to 4 pieces.

In addition, the bevel angle of the cutting edge portion of the end mill is preferably 0 to less than 15°, and may be set to 3 to 12°. When the said bevel angle becomes 15 degrees or more, it will become easy to form a chip|tip in a blade.

In addition, the clearance angle of the cutting edge portion of the end mill is preferably greater than 0° and less than 20°, and may be 3 to 15°. When the above-mentioned clearance angle is 0°, it will cause friction with the film, and when it is 20° or more, the cutting edge will become easily chipped.

In addition, the helix angle of the blade portion of the end mill is preferably -75° to 75°, and may be set to -65° to 65°. When the above-mentioned helix angle exceeds the above-mentioned range, it becomes easy to cause chip discharge failure.

In addition, the tool diameter (outer diameter) φ of the cutting edge portion of the end mill is preferably 3 to 30 mm, and may be 5 to 25 mm. When the above-mentioned tool diameter φ is less than 3 mm, it becomes easy to break, and when it exceeds 30 mm, it becomes difficult to perform fine special-shaped processing.

In addition, as manufacturing conditions when using an end mill, the feed rate of the blade portion of the end mill is preferably 100 to 10000 mm/minute, and may be 200 to 8000 mm/minute.

In addition, the rotational speed of the blade portion of the end mill is preferably 1,000 to 120,000 rpm, may be 2,000 to 60,000 rpm, or may be 3,000 to 50,000 rpm. When the rotation speed is lower than 1000 rpm, cracks may be caused. On the other hand, when the rotation speed is faster than 60000 rpm, heat may be generated to cause damage to the polarizing plate or the like.

The polarizing plate used in the present invention is not particularly limited, and known polarizing plates can be appropriately used. As said polarizing plate, the polarizing plate manufactured by stretch molding, the polarizing plate manufactured by coating molding, etc. are mentioned, for example.

As the polarizer, it is not particularly limited, and various polarizers can be used. As the polarizer, for example, it is possible to adsorb iodine or Dichroic materials such as dichroic dyes and uniaxially stretched films, dehydration-treated polyvinyl alcohol or polyvinyl chloride dehydrochloric acid-treated polyene-based oriented films, etc. Among these, a polarizer formed of a polyvinyl alcohol-based film and a dichroic substance such as iodine is particularly preferable.

Among the materials of the polyvinyl alcohol-based film suitable for polarizers, polyvinyl alcohol or derivatives thereof can be used. As derivatives of polyvinyl alcohol, in addition to polyvinyl formaldehyde and polyvinyl acetal, unsaturated carboxylic acids such as olefins such as ethylene and propylene, acrylic acid, methacrylic acid, crotonic acid, etc., and Modified substances such as alkyl esters and acrylamide. The degree of polymerization of polyvinyl alcohol is preferably about 1,000 to 10,000, and polyvinyl alcohol with a degree of saponification of about 80 to 100 mol% is usually used.

The above-mentioned polyvinyl alcohol-based film (unstretched film) is subjected to at least a uniaxial stretching treatment and an iodine dyeing treatment according to conventional methods. In addition, boric acid treatment and iodide ion treatment can be further performed. Also, the polyvinyl alcohol-based film (stretched film) subjected to the above treatment was dried according to a conventional method to obtain a polarizer.

The polarizing plate used in the present invention may be a polarizing plate in which a protective film is bonded to at least one side of a polarizer through an adhesive. The protective film may be bonded to one side or both sides of the polarizer. The protective film may also have other optical functions at the same time, and may be formed by laminating other layers.

In the case where the above polarizing plate has protective films on both sides of the polarizer, the protective film on one side and the protective film on the other side may be the same protective film or different protective films. Also, at least one protective film may be used per one side, or a laminate of two or more layers may be used.

The thickness of the protective film can be appropriately determined, but generally, it is preferably about 1 to 500 μm in terms of workability such as strength and handleability, and thin layer properties. Especially preferably 1~300μm, more preferably 5~200μm.

Examples of materials constituting the protective film include thermoplastic resins excellent in transparency, mechanical strength, thermal stability, and moisture barrier properties. Also, when optical isotropy is required for the protective film, it is desirable to select a resin with a small intrinsic birefringence. Specific examples of such thermoplastic resins include polyester resins, polyether resins, polycarbonate resins, polyamide resins, polyimide resins, polyamide resins, Olefin-based resins, (meth)acrylic resins, norbornene-based resins, polyarylate-based resins, and mixtures of these resins. In addition, thermosetting resins such as (meth)acrylic resins or ultraviolet curable resins may be used. Among the above, from the viewpoint of moisture permeability and optical properties, (meth)acrylic resins, polyimide resins, and norbornene resins are preferably used.

As the protective film, the protective film on the cell side may also have a phase difference function for viewing angle compensation, and the opposite side of the protective film on the cell side may have a phase difference or may not have a phase difference.

Easy-to-adhesive treatment can be performed on the surface of the polarizer that is bonded to the protective film. Examples of the easy-adhesive treatment include dry treatments such as plasma treatment and corona treatment, chemical treatments such as alkali treatment (saponification treatment), and coating treatment to form an easily-adhesive layer. Among these treatments, coating treatment or alkali treatment for forming an adhesive layer is preferable. Various easy-adhesive materials such as polyol resins, polycarboxylic acid resins, and polyester resins can be used for the formation of the easily-adhesive layer. Furthermore, the thickness of the easy-adhesive layer is usually set at about 0.001-10 μm, preferably about 0.001-5 μm, especially about 0.001-1 μm.

On the surface of the above-mentioned protective film that does not adhere to the polarizer, a hard coating layer or anti-reflection treatment, anti-sticking, diffusion and even anti-glare treatment can also be applied.

The adhesive constituting the above-mentioned polarizing plate is not particularly limited as long as it is optically transparent, and various forms of adhesives such as water-based, solvent-based, hot-melt, and radical curing types can be used, but water-based adhesives or Radical hardening adhesives are preferred.

The water-based adhesive for forming the adhesive layer is not particularly limited, but examples include vinyl polymer-based, gelatin-based, vinyl-based latex-based, polyurethane-based, isocyanate-based, and polyester-based adhesives. Department, epoxy system, etc.

As radical curing adhesives, various adhesives such as electron beam curing type, ultraviolet curing type, active energy ray curing type, thermosetting type, etc. can be listed, but active energy ray curing adhesives that can be cured in a short time Adhesives are preferred.

The method for manufacturing a special-shaped polarizing plate of the present invention is a method for manufacturing a special-shaped polarizing plate having a concave R portion and/or a hole, and is characterized in that it includes the step of forming the above-mentioned concave R portion by using a cutting mechanism such as an end mill. In the cutting mechanism, the cutting edge is brought into contact with the cutting surface from the lateral direction to perform cutting.

In the production of the polarizing plate itself at the stage before forming the concave R portion and/or the hole portion used in the present invention, a known method can be appropriately used. In addition, in the manufacturing method of the present invention, the step of forming the above-mentioned concave R portion by using a cutting mechanism such as an end mill that makes the cutting edge abut against the cutting surface from the lateral direction and cuts may be performed after the polarizing plate itself is manufactured. Yes, it may be carried out in the manufacturing process of the polarizing plate itself as the case may be.

In the production stage of the polarizing plate itself before forming the concave R portion and/or the hole portion, well-known methods can be appropriately used for cutting and the like. For example, at the stage of making it a certain size before microfabrication, it is preliminarily made into a rectangular shape by using a conventional laser or the like, and after forming fine concave R portions and/or holes It can also be used suitably as the manufacturing method etc. of this invention in the stage of a part. In the former stage, the shape of the polarizing plate at the time of cutting is not particularly limited, but generally it only needs to be a quadrangle and can be cut in the direction of the absorption axis and the direction of the transmission axis of the polarizing plate. Also, in the former stage, for example, cutting by laser may be performed on at least one end side, but it is preferably performed in the absorption axis direction, the transmission axis direction, or both.

The production of the polarizing plate itself can be carried out by, for example, a process of bonding the above-mentioned polarizer and the above-mentioned protective film using the above-mentioned adhesive agent. In the obtained polarizer, the protective film can be provided on one or both sides of the polarizer through the adhesive layer formed by the above polarizer adhesive.

In addition, the above-mentioned polarizing plate can be used as an optical film laminated with other optical layers in practical applications. The irregular-shaped polarizing plate in the manufacturing method of the irregular-shaped polarizing plate of the present invention also includes an irregular-shaped optical film in which at least one polarizing plate is laminated together with the irregular-shaped polarizing plate. In the manufacturing method of the present invention, it can be set to make the optical film after the processing step of first making the polarizer itself into a special shape, or it can be set to make the optical film first and then go through the processing step of making a special shape. Both may be used in combination as appropriate.

Regarding the above-mentioned optical layer, although there is no particular limitation, it is possible to use one or more optical layers for the formation of liquid crystal display devices, such as reflective plates or semi-transmissive plates, retardation plates (including 1/2 or 1/4 wavelength plate), viewing angle compensation film, etc. In particular, a reflective polarizing plate or a semi-transmitting polarizing plate in which a reflecting plate or a semi-transmitting reflecting plate is laminated on the above-mentioned polarizing plate, or an elliptical polarizing plate in which a retardation plate is further laminated on the polarizing plate is preferable. Or a circular polarizer, a polarizer with a wide viewing angle made by laminating a viewing angle compensation film on a polarizer, or a polarizer made by laminating a brightness enhancing film on a polarizer.

An adhesive layer for bonding to other members such as a liquid crystal cell may also be provided on the aforementioned polarizing plate or the optical film on which at least one polarizing plate is laminated. The adhesive forming the adhesive layer is not particularly limited, but can be appropriately selected and used, for example, acrylic polymers, polysiloxane polymers, polyesters, polyurethanes, polyamides, polyethers, fluorine-based polymers, etc. Or rubber-based polymers as adhesives for base polymers. In particular, adhesives that are excellent in optical transparency like acrylic adhesives, exhibit appropriate wettability, cohesiveness, and adhesive properties, and are excellent in weather resistance and heat resistance can be preferably used.

Attaching an adhesive layer to one side or both sides of a polarizing plate or an optical film can be performed by an appropriate method. As this example, for example, the following method can be mentioned: preparing the base polymer or its composition in a solvent formed by dissolving or dispersing a suitable solvent such as toluene or ethyl acetate alone or in a mixture of 10~ Adhesive solution of about 40% by weight, and the solution is directly attached to a polarizing plate or an optical film by a suitable spreading method such as a casting method or a coating method, or formed on a separator according to the above Adhesive layer, and transfer it to a polarizing plate or an optical film, etc.

The adhesive layer can also be made as a superimposed layer of adhesive layers of different compositions or types, and is arranged on one or both sides of a polarizing plate or an optical film. Also, when it is installed on both sides, it is also possible to form adhesive layers of different compositions, types, thicknesses, etc. on the front and back of the polarizing plate or optical film. The thickness of the adhesive layer can be appropriately determined according to the purpose of use and the adhesive force, etc., and is generally 1-500 μm, preferably 5-200 μm, especially 10-100 μm.

The exposed surface of the adhesive layer is temporarily installed and covered with a separator for the purpose of preventing contamination and the like until it is supplied to actual use. In this way, it is possible to prevent the contact with the adhesive layer in normal operating conditions. As the separator, in addition to the above-mentioned thickness conditions, more appropriate separators than conventional ones can be used, such as laminates of plastic films, rubber sheets, paper, cloth, non-woven fabrics, nets, foam sheets or metal foils, etc. Appropriate thin sheets need to be coated with a suitable release agent such as silicone-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide-based, such as a separator.

The above-mentioned polarizing plate or optical film can be preferably used in the formation of various devices such as liquid crystal display devices and the like. [Example]

Hereinafter, examples etc. which concretely show the structure and effect of this invention are demonstrated.

EXAMPLES, COMPARATIVE EXAMPLES The processing in Examples 1-2 and Comparative Examples 1-3 was carried out under the conditions shown in Table 1 below and processed into the processed shapes shown in FIG. 6 . Also, a laminate obtained by laminating a surface protection film (PPF-100T) manufactured by Nitto Denko Co., Ltd. on a polarizing plate (NPF-CWQ1463VDUAG380-ACJ) manufactured by Nitto Denko Co., Ltd. was used as a workpiece. In addition, the unit in FIG. 6 is mm. [Table 1]

(Measurement and evaluation of degree of freedom of shape) The degree of freedom of shape of each polarizing plate processed and manufactured by the Example and the comparative example was measured and evaluated as follows. In each of the examples and comparative examples, processing was performed on the polarizing plate to manufacture irregular-shaped portions such as convex R portions, concave R portions, and hole portions as shown in FIG. "○" and "×" when impossible. In addition, when the formation of the processed part is possible, the minimum value that can be formed is measured using a three-dimensional dimension measuring device QV-Apex606 manufactured by Mitutoyo Corporation.

(Measurement of Dimensional Accuracy and Right Angle Accuracy) The dimensional accuracy and right angle accuracy of the various polarizing plates processed and manufactured in Examples and Comparative Examples were measured as follows. Each dimensional accuracy was observed and calculated with an optical microscope BX51 manufactured by OLIMPUS Corporation and a three-dimensional dimension measuring instrument QV-Apex606 manufactured by Mitutoyo Corporation. Again, no matter which one is the same result.

(Measurement and evaluation of edge portion quality) The edge portion quality of each different-shaped polarizing plate processed and manufactured in Examples and Comparative Examples was measured and evaluated as follows. In each of the examples and comparative examples, the case where cracks, breakage, or discoloration did not occur in each end after processing and manufacture was evaluated as "○", and the case where cracks, breakage, or discoloration occurred was evaluated as to "×". In addition, when cracks, fractures, or discoloration occurred, the size and the like of these defects were measured using a microscope (optical microscope BX51 manufactured by Olimpus Co., Ltd.).

The obtained results are shown in Table 2 below. [Table 2]

In Example 1, in the concave R, the minimum value of R is 3mm. Also, in Example 2, in the concave R, the minimum value of R is 62.5 mm. On the other hand, in Comparative Examples 1 and 2, cracks of up to 100 μm occurred. Also, in Comparative Examples 1 and 2, breakage of a maximum of 1000 μm occurred. Also, in Comparative Example 3, discoloration occurred at a maximum of 50 μm.

As described above, when using the manufacturing method in the embodiment of the present application, the occurrence of cracks, breakage, and discoloration can be suppressed, and a special-shaped polarizing plate particularly having small-diameter concave R portions and/or hole portions can be easily obtained. On the other hand, when the production method in Comparative Example was used, cracks, breakage, or discoloration occurred.

In addition, the processing in Examples 3-5 and Comparative Examples 4-5 was carried out under the conditions shown in Table 3 below and processed into the processed shape shown in FIG. 7 . Also, a laminate obtained by laminating a surface protection film (RP296C) manufactured by Nitto Denko Co., Ltd. on a polarizing plate (APCFU4MS) manufactured by Nitto Denko Co., Ltd. was used as a workpiece. In addition, the processing conditions by the Thomson die in Comparative Example 5 were the same as those in Comparative Example 1. In addition, R of the recessed part in FIG. 7 is 3mm.

(Measurement of delamination amount) About the measurement of the delamination amount of each polarizing plate processed and manufactured by the Example and the comparative example, it measured as follows. The obtained polarizing plates of different shapes were observed under a microscope, and the distance from the edge to the deepest point where delamination occurred was measured for each of the corners, straight lines, and recesses.

The obtained results are shown in Table 3 below. [table 3]

In Examples 3 to 5, the maximum value of the delamination amount was less than 0 μm in any of the corner portion, straight line portion, and concave portion. On the other hand, in Comparative Examples 4 to 5, the maximum value of the delamination amount was 60 μm or more in any of the corner portion, straight line portion, and concave portion.

As mentioned above, in the case of processing at a cutting angle of 60° or more, the occurrence of delamination of the special-shaped polarizing plate can be more preferably suppressed.

FIG. 1 shows an example of a special-shaped polarizing plate obtained by the method for producing a special-shaped polarizing plate of the present invention. FIG. 2 shows an example of an embodiment of the method for manufacturing a special-shaped polarizing plate of the present invention. FIG. 3 shows an example of an embodiment of the method for manufacturing a special-shaped polarizing plate of the present invention. Fig. 4 shows an example of an end mill in the method of manufacturing a special-shaped polarizing plate of the present invention. Fig. 5 shows an example of an end mill in the method of manufacturing a special-shaped polarizing plate of the present invention. Fig. 6 is a diagram showing the processed shapes implemented in the embodiment of the present invention. Fig. 7 is a diagram showing the processed shapes implemented in the embodiment of the present invention.

(none)

Claims (12)

A method for manufacturing a special-shaped polarizing plate, which is a method for manufacturing a special-shaped polarizing plate with a concave R portion, and includes the step of using a cutting mechanism to form the aforementioned concave R portion. The cutting mechanism is to make the cutting edge contact the cutting surface from the transverse direction For cutting, the radius of the concave R portion is 5 mm or less, the cutting mechanism is an end mill, and the cutting angle between the machining direction and the cutting edge surface of the cutting edge is more than 60°. The method for manufacturing a special-shaped polarizing plate as claimed in Claim 1, wherein the cutting angle between the processing direction and the blade surface of the blade is 65°-90°. The method for manufacturing a special-shaped polarizing plate according to claim 1, wherein the cutting angle between the processing direction and the blade surface of the blade is 90°. A manufacturing device for a special-shaped polarizing plate, which is a manufacturing device for a special-shaped polarizing plate having a concave R portion, and is provided with a cutting mechanism for making a cutting edge abut against a cutting surface from a lateral direction and cutting, the radius of the concave R portion is 5 mm or less, and the above-mentioned The cutting mechanism is an end mill, and the cutting angle formed by the machining direction of the cutting mechanism and the cutting edge surface of the cutting edge exceeds 60°. The device for manufacturing a special-shaped polarizing plate according to claim 4, wherein the cutting angle between the processing direction and the blade surface of the blade is 65°-90°. The device for manufacturing a special-shaped polarizing plate according to claim 4, wherein the cutting angle between the processing direction and the blade surface of the blade is 90°. A method for manufacturing a special-shaped polarizing plate, which is a method for manufacturing a special-shaped polarizing plate with a hole, and includes the step of using an end mill to form the hole, the radius of the hole is 5 mm or less, and the processing direction is the same as the end mill. The cutting angle formed by the blade face is more than 60°. The method for manufacturing a special-shaped polarizing plate as claimed in claim 7, wherein the cutting angle between the processing direction and the blade surface of the blade is 65°-90°. The method for manufacturing a special-shaped polarizing plate according to claim 7, wherein the cutting angle between the processing direction and the blade surface of the blade is 90°. A manufacturing device of a special-shaped polarizing plate is a manufacturing device of a special-shaped polarizing plate having a hole, equipped with an end mill, the radius of the aforementioned hole is 5 mm or less, and the cutting angle between the machining direction and the blade surface of the aforementioned end mill is more than 60°. The device for manufacturing a special-shaped polarizing plate according to claim 10, wherein the cutting angle between the processing direction and the blade surface of the blade is 65°-90°. The device for manufacturing a special-shaped polarizing plate according to claim 10, wherein the cutting angle between the processing direction and the blade surface of the blade is 90°.

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