JP6654113B2 - Optical display panel manufacturing method and optical display panel manufacturing system - Google Patents

Description

  The present invention relates to an optical display panel manufacturing method and an optical display panel manufacturing system.

  An optical film in which a release film, a pressure-sensitive adhesive layer, an optical functional film (typically, a polarizing film) and a surface protective film are laminated in this order is formed in a roll shape. An optical film obtained by cutting (half-cutting) the optical film fed from the roll-shaped optical film in the width direction of the pressure-sensitive adhesive layer, the optical functional film and the surface protective film while leaving a release film, and cutting the optical film. (Hereinafter, also referred to as a “roll-to-panel method”) in which the release film is peeled off from the substrate and the optical film is bonded to the optical cell via the exposed adhesive layer (for example, Patent Documents 1 and 2). reference).

  On the other hand, as an optical film lamination method different from the roll-to-panel method, an optical film that has been made into a single-wafer state is pasted to the optical cell via the adhesive layer that has been released by exfoliating the release film. There is a matching method (hereinafter, also referred to as a “sheet-to-panel method”) (for example, see Patent Document 3).

JP 2011-123208 A JP 2015-049115 A JP 2006-039238 A

  By the way, at the manufacturing site of optical display panels such as liquid crystal display panels, there is a new case of manufacturing optical display panels of the same configuration using not only the roll-to-panel method but also the sheet-to-panel method. It has occurred. For example, Patent Document 2 discloses that an optical display panel is continuously manufactured using a roll-to-panel method, and a rework process is performed on an optical display panel determined to be defective. When not many defective products are generated, a sheet-to-panel method may be used when a new optical function film is bonded to the optical cell in the rework processing. Also, for example, when optical display panels of the same configuration must be mass-produced in a short period of time, the roll-to-panel method cannot cover all the supply amount, and the sheet-to-panel method is used together. Is also conceivable.

  In recent years, as optical display panels have become thinner, thinner optical functional films (for example, polarizing films having a thickness of 60 μm or less) have been developed, including polarizing films. Such a thin optical functional film has a low waist (elastic modulus) and is likely to be twisted, curled, and the like.

  According to the roll-to-panel method, a thin optical function film is transported to a bonding position in a state of being laminated on a carrier film (release film), and the optical function film is released from the carrier film (release film) at the bonding position. Since the film is peeled off and the optical function film is bonded to the optical cell, a thin optical function film can be continuously bonded to the optical cell while suppressing the occurrence of twist, curl, and the like. However, in the sheet-to-panel method, it is difficult to handle such as transporting the optically functional film in a single-wafer state, peeling off the release film, and laminating the optically functional film to the liquid crystal cell. There is a concern that the yield will decrease.

  The present invention is to suitably manufacture an optical display panel having the same configuration as an optical display panel manufactured by a roll-to-panel method even when a thin optical functional film is bonded to an optical cell by a sheet-to-panel method. It is an object of the present invention to provide a manufacturing method and a manufacturing system of an optical display panel that can be used.

The present invention relates to an optical display panel having an optical film in which a pressure-sensitive adhesive layer, an optical functional film, and a first surface protective film are laminated in this order, and an optical cell in which the optical film is provided on one surface. An optical display panel manufacturing method for re-attaching a sheet-shaped optical film having the same configuration as the removed optical film to the one surface of the optical cell from which the optical film has been removed,
Release film, pressure-sensitive adhesive layer, optical functional film, first surface protection film and second surface protection film is peeled off from the sheet-shaped optical film laminated in this order, the release film, the pressure-sensitive adhesive layer A re-pasting step of pasting the sheet-like optical film to the one surface of the optical cell and re-manufacturing the optical display panel,
A second surface protection film removing step of removing the second surface protection film after the re-sticking step.

  The above invention may further include a removing step of removing the optical film from the optical display panel based on a result of inspecting the optical cell to which the optical film is attached.

  The above invention may further include an inspection step of inspecting the optical cell to which the optical film is attached.

In the above invention, the strip-shaped optical film formed by winding a strip-shaped optical film in which a release film, an adhesive layer, an optical functional film, and a first surface protection film are laminated in this order is wound. An optical film, a cutting step of cutting leaving the release film in a direction orthogonal to the longitudinal direction of the optical film,
A step of attaching the optical film from which the release film has been peeled off to the one surface of the optical cell via the pressure-sensitive adhesive layer.

In the above invention, the release film, the pressure-sensitive adhesive layer, the optical function film, the first surface protection film are laminated in this order, and the optical film having cuts formed at predetermined intervals except for the release film is wound. The optical film is unwound from a roll-shaped optical film, and the optical film from which the release film has been peeled off is attached to the one surface of the optical cell via the adhesive layer. Is also good.
According to this configuration, it is not necessary to cut (half-cut) the optical film in the roll-to-panel method.

The above invention is a roll-shaped optical film in which a release film, a pressure-sensitive adhesive layer, an optical functional film, and a first surface protection film are laminated in this order,
A step of preparing an optical film set having a sheet-shaped optical film in which the release film, the pressure-sensitive adhesive layer, the optical functional film, the first surface protective film, and the second surface protective film are laminated in this order, Further, it may be included. The “preparing step” may be a manufacturing step or a step of transporting from another location and setting it at a predetermined position.

In the above invention, the release film, the pressure-sensitive adhesive layer, the optical function film, the first surface protection film are laminated in this order, and the optical film having cuts formed at predetermined intervals except for the release film is wound. Roll-shaped optical film,
A step of preparing an optical film set having a sheet-like optical film in which the release film, the pressure-sensitive adhesive layer, the optical functional film, the first surface protection film, and the second surface protection film are laminated in this order, May be included. The “preparing step” may be a manufacturing step or a step of transporting from another location and setting it at a predetermined position.
According to this configuration, it is not necessary to cut (half-cut) the optical film in the roll-to-panel method.

Another invention relates to an optical display panel having an optical film in which a pressure-sensitive adhesive layer, an optical functional film, and a first surface protection film are laminated in this order, and an optical cell in which the optical film is provided on one surface. An optical display panel manufacturing system, in which the one-sided optical film having the same configuration as the removed optical film is attached again to the one surface of the optical cell from which the optical film has been removed,
The release film, the pressure-sensitive adhesive layer, the optical functional film, the first surface protection film and the second surface protection film are separated from the sheet-shaped optical film laminated in this order, and the release film is peeled off. A re-pasting unit for pasting the optical display panel by pasting the sheet-like optical film on the one surface of the optical cell via
A second surface protection film removing unit that removes the second surface protection film after the processing of the re-sticking unit.

  The above invention may further include an optical film removing unit that removes the optical film from the optical display panel based on a result of inspecting the optical cell to which the optical film is attached.

  The above invention may further include an inspection unit that inspects the optical cell to which the optical film is attached.

In the above invention, the strip-shaped optical film formed by winding a strip-shaped optical film in which a release film, an adhesive layer, an optical functional film, and a first surface protection film are laminated in this order is wound. An optical film, a cutting step of cutting leaving the release film in a direction orthogonal to the longitudinal direction of the optical film,
A step of attaching the optical film from which the release film has been peeled to the one surface of the optical cell via the pressure-sensitive adhesive layer.

In the above invention, the release film, the pressure-sensitive adhesive layer, the optical function film, the first surface protection film are laminated in this order, and the optical film having cuts formed at predetermined intervals except for the release film is wound. The optical film that has been unwound from the roll-shaped optical film, the release film has been peeled off, and the optical film further has an affixing unit that is attached to the one surface of the optical cell via the adhesive layer. Is also good.
According to this configuration, it is not necessary to cut (half-cut) the optical film in the roll-to-panel method.

The above invention is a roll-shaped optical film in which a release film, a pressure-sensitive adhesive layer, an optical functional film, and a first surface protection film are laminated in this order,
A production unit for producing an optical film set having a sheet-shaped optical film in which a release film, an adhesive layer, an optical functional film, a first surface protection film, and a second surface protection film are laminated in this order; May be further provided.

In the above invention, the release film, the pressure-sensitive adhesive layer, the optical function film, the first surface protection film are laminated in this order, and the optical film having cuts formed at predetermined intervals except for the release film is wound. Roll-shaped optical film,
A release unit, a pressure-sensitive adhesive layer, an optical functional film, a first surface protection film and a second production unit for producing an optical film set having a sheet-like optical film having a configuration in which the second surface protection film is laminated in this order, It may also have.
According to this configuration, it is not necessary to cut (half-cut) the optical film in the roll-to-panel method.

  The “roll-to-panel method” is a method in which a release film is peeled from an optical film fed from a roll-shaped optical film, and the optical film is bonded to an optical cell via an exposed adhesive layer. Here, it is sufficient that cuts at predetermined intervals are formed in the optical film in the width direction thereof before the release film is peeled, leaving the release film. A cut may be formed in the width direction of the optical film before the optical film is fed out from the roll, or a cut may be formed in the width direction of the optical film before the release film is peeled off after being fed out.

  The “sheet-to-panel method” is a method in which a release film is peeled from an optical film that has been made into a single-wafer state, and the optical film is bonded to an optical cell via an exposed adhesive layer.

  In the above invention, when a polarizing film is used as the optical functional film (the first optical functional film, the second optical functional film), or when a polarizing film is included as one member of the configuration of the optical functional film, In the roll-shaped and sheet-shaped optical films (first optical film and second optical film) and optical film raw materials (first optical film raw material and second optical film raw material), the absorption axis direction of the polarizing film is There is no particular limitation as long as the object of the invention is not hindered. That is, even if the roll-to-panel method and the sheet-to-panel method are used in combination, as long as the combination is such that an optical display panel having the same configuration can be manufactured, the roll-shaped optical film (first In the optical film, the second optical film) and the optical film raw material (the first optical film raw material and the second optical film raw material), the polarizing film may have its absorption axis direction parallel to the longitudinal direction or orthogonal to the longitudinal direction. Alternatively, it may be oblique (for example, a direction making an angle of 45 ° with the longitudinal direction). The absorption axis direction of the rectangular sheet-shaped polarizing film may be parallel to the longitudinal direction, may be perpendicular to the longitudinal direction, or may be oblique (for example, a direction forming an angle of 45 ° with the longitudinal direction). Further, the absorption axis direction of the square sheet-shaped polarizing film may be parallel to an arbitrary side or may be oblique (for example, a direction forming an angle of 45 ° with the side).

  In the above invention, the optical cell may be a VA mode or IPS mode liquid crystal cell or an organic EL cell.

  The shape of the optical cell is not particularly limited, and may be a square or a rectangle as long as it has a pair of opposing sides and another pair of opposing sides. Usually, one set of opposing sides of the optical cell and another set of opposing sides are orthogonal to each other.

  According to the present invention, since the sheet-shaped optical film provided with the second surface protection film has improved handling properties, the occurrence of twist, curl, and the like is suppressed, and the sheet-to-panel is suppressed. It can be suitably bonded to the optical cell by using the method. Then, by removing (for example, peeling) the second surface protection film from the sheet-like optical film bonded to the optical display panel, the result is the same as that of the optical display panel manufactured by the roll-to-panel method. An optical display panel having a laminated structure can be manufactured. That is, according to the optical film set of the present invention, when bonding the optical film to the optical cell, even when the roll-to-panel method and the sheet-to-panel method are used together, the optical display panel having the same configuration Can be suitably produced.

Schematic diagram showing the optical film set Schematic diagram showing a method for manufacturing a roll-shaped first optical film. Schematic diagram showing a method for producing a single-leaf first optical film. Schematic diagram of a continuous production system for an optical display panel according to the first embodiment. Diagram showing the remanufacturing process

<Optical film set>
First, the optical film set used in the present invention will be described. FIG. 1 is a schematic diagram showing an optical film set. The upper part of FIG. 1 shows an enlarged side view, a plan view and a partial cross-sectional view of the first optical film 1 in a roll form. The lower part of FIG. 1 shows an enlarged side view, a plan view, and a partial cross-sectional view of the first optical film 2 having a sheet shape. The first optical film 1 in the form of a roll has a first release film 11, a first pressure-sensitive adhesive layer 12, a first optical functional film 13, and a first surface protection film 14 laminated in this order.

  The roll-shaped first optical film 1 is used for manufacturing an optical display panel by a roll-to-panel method. In such a case, the strip-shaped first optical film 10 having a width a that has been fed from the roll-shaped first optical film 1 is cut by the cutting unit C at a predetermined interval b while leaving the first release film 11. . Symbol s is a cut formed in the first optical film 10 by the above cutting.

  In addition, the sheet-shaped first optical film 2 includes a first release film 21, a first adhesive layer 22, a first optical functional film 23, a first surface protection film 24, and a second surface protection film 25 laminated in this order. Have been. The size of the sheet-like first optical film 2 is vertical a and horizontal b. The sheet-like first optical film 2 is used for manufacturing an optical display panel by a sheet-to-panel method.

  In the present embodiment, the first release film 11 and the first release film 21 have the same configuration. The first pressure-sensitive adhesive layer 12 and the first pressure-sensitive adhesive layer 22 have the same configuration. The first optical function film 13 and the first optical function film 23 have the same configuration. The first surface protection film 14, the first surface protection film 24, and the second surface protection film 25 have the same configuration. The “same configuration” means that not only the material, thickness and the like completely match but also substantially the same (for example, the same in manufacturing quality).

  In the present embodiment, the first surface protection film 14 (or 24) has a first base film and a first pressure-sensitive adhesive layer, and the first optical functional film 13 (or 23) is interposed via the first pressure-sensitive adhesive layer. ). As another embodiment, the first surface protection film 14 (or 24) may be a self-adhesive film.

  In the present embodiment, the second surface protection film 25 has a second base material film and a second pressure-sensitive adhesive layer, and is laminated on the first surface protection film 24 via the second pressure-sensitive adhesive layer. In another embodiment, the second surface protection film 25 may be a self-adhesive film.

(Relationship between phase separation forces)
In addition, the peel strength between the first surface protection film 24 and the first optical function film 23 is larger than the peel strength between the second surface protection film 25 and the first surface protection film 24. According to this, the second surface protection film 25 can be peeled more smoothly. As the measurement of the peeling force, for example, a tensile tester can be used. The peeling condition is measured at 180 ° peeling at 0.3 m / min. The peeling force is controlled by the composition and thickness of the pressure-sensitive adhesive.

The magnitude relationship of the peeling force between the layers in the single-sheet first optical film 2 is as follows.
Delamination force A between the first release film 21 and the first pressure-sensitive adhesive layer 22;
Delamination force B between the first pressure-sensitive adhesive layer 22 and the first optical function film 23,
A delamination force C between the first optical function film 23 and the first surface protection film 24,
When the delamination force D between the first surface protection film 24 and the second surface protection film 25 is defined as:
A <B, A <C, and A <D.
Preferably, A <D <C ≦ B or A <D <B ≦ C.
More preferably, A <D <C <B.
According to the relationship between the inter-phase peeling forces, when the first release film is peeled, it is possible to suppress the second surface protection film from being peeled.

<Optical function film>
The first optical function films 13 and 23 are not particularly limited as long as they are films having an optical function, and examples thereof include a polarizing film, a retardation film, a brightness enhancement film, and a diffusion film. .

(Polarizing film)
In the present embodiment, from the viewpoint of thinning, it is preferable to use a polarizing film having a thickness (total thickness) of 60 μm or less, more preferably 55 μm or less, and still more preferably 50 μm or less. As the polarizing film, for example, (1) a structure in which protective films (sometimes referred to as “polarizer protective films”) are laminated on both sides of a polarizer (sometimes referred to as “both protective polarizing films”). , (2) a configuration in which a protective film is laminated only on one side of a polarizer (sometimes referred to as a “single-protective polarizing film”).

(Polarizer)
A polarizer using a polyvinyl alcohol-based resin is used. Examples of the polarizer include, for example, a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, a hydrophilic polymer film such as an ethylene-vinyl acetate copolymer-based partially saponified film, and dichroic properties of iodine and a dichroic dye. Examples thereof include a uniaxially stretched film obtained by adsorbing a substance, and a polyene-based oriented film such as a dehydrated product of polyvinyl alcohol and a dehydrochlorinated product of polyvinyl chloride. Among these, a polarizer composed of a polyvinyl alcohol-based film and a dichroic substance such as iodine is preferable.

  A polarizer obtained by dyeing a polyvinyl alcohol-based film with iodine and uniaxially stretching can be produced by, for example, dyeing polyvinyl alcohol by immersing it in an aqueous solution of iodine and stretching the film to 3 to 7 times its original length. If necessary, it may contain boric acid, zinc sulfate, zinc chloride, or the like, or may be immersed in an aqueous solution such as potassium iodide. Further, if necessary, the polyvinyl alcohol-based film may be immersed in water and washed with water before dyeing. By washing the polyvinyl alcohol-based film with water, dirt on the surface of the polyvinyl alcohol-based film and an anti-blocking agent can be washed, and by swelling the polyvinyl alcohol-based film, the effect of preventing unevenness such as uneven dyeing can be obtained. is there. Stretching may be performed after dyeing with iodine, may be performed while dyeing, or may be dyed with iodine after stretching. Stretching can be performed in an aqueous solution of boric acid or potassium iodide or in a water bath.

  The thickness of the polarizer is preferably 10 μm or less, more preferably 8 μm or less, further preferably 7 μm or less, and further preferably 6 μm or less from the viewpoint of thinning. On the other hand, the thickness of the polarizer is preferably 2 μm or more, more preferably 3 μm or more. Such a thin polarizer has less thickness unevenness, is excellent in visibility, and has little dimensional change, and thus has excellent durability against thermal shock. On the other hand, a polarizing film containing a polarizer having a thickness of 10 μm or less has a remarkably low stiffness (elastic modulus), and thus is highly likely to cause twisting, curling, and the like in a sheet-to-panel system. Therefore, the present invention is particularly suitable for the polarizing film.

As a thin polarizer, typically,
Patent No. 4751486,
Patent No. 4,751,481,
Patent No. 4815544,
Patent No. 5048120,
WO 2014/077759 pamphlet,
International Publication No. 2014/077636 pamphlet,
And the like, or a thin polarizer obtained from the production method described therein.

The polarizer has an optical property represented by a single transmittance T and a degree of polarization P of the following formula: P>-(10 ^0.929T-42.4 -1) × 100 (where T <42.3); Or
P ≧ 99.9 (however, T ≧ 42.3)
It is preferable to satisfy the above condition. A polarizer configured to satisfy the above conditions has the performance required primarily as a display for a liquid crystal television using a large display element. Specifically, the contrast ratio is 1000: 1 or more and the maximum luminance is 500 cd / m ² or more. As another application, for example, it is attached to the viewing side of the organic EL cell.

  Among the thin polarizers, Japanese Patent No. 4751486 and Japanese Patent No. 4751486, which can be stretched at a high magnification to improve the polarization performance among manufacturing methods including a stretching step and a dyeing step in a state of a laminate. Preferred are those obtained by a production method including a step of stretching in an aqueous boric acid solution as described in JP-B-47515481 and JP-B-4815544, and particularly described in JP-B-47515481 and JP-B-4815544. What is obtained by the manufacturing method including the process of auxiliary | assistant air stretching before extending | stretching in a boric acid aqueous solution which has a certain thing is preferable. These thin polarizers can be obtained by a manufacturing method including a step of stretching a polyvinyl alcohol-based resin (hereinafter, also referred to as a PVA-based resin) layer and a resin substrate for stretching in a laminate state and a step of dyeing. According to this manufacturing method, even if the PVA-based resin layer is thin, it can be stretched without any trouble such as breakage due to stretching because it is supported by the stretching resin base material.

(Protective film (polarizer protective film))
As a material constituting the protective film, a material having excellent transparency, mechanical strength, heat stability, moisture barrier property, isotropy, and the like is preferable. For example, polyester polymers such as polyethylene terephthalate and polyethylene naphthalate; cellulose polymers such as diacetyl cellulose and triacetyl cellulose; acrylic polymers such as polymethyl methacrylate; styrene such as polystyrene and acrylonitrile-styrene copolymer (AS resin) Polymers, polycarbonate polymers and the like. In addition, polyethylene, polypropylene, polyolefin having a cyclo- or norbornene structure, polyolefin polymers such as ethylene-propylene copolymer, vinyl chloride polymers, amide polymers such as nylon and aromatic polyamide, imide polymers, and sulfone polymers , Polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, arylate polymer, polyoxymethylene polymer, epoxy polymer, or the above Blends of polymers and the like are also mentioned as examples of the polymer forming the protective film.

  The protective film may contain one or more optional additives. Examples of the additive include an ultraviolet absorber, an antioxidant, a lubricant, a plasticizer, a release agent, a coloring inhibitor, a flame retardant, a nucleating agent, an antistatic agent, a pigment, a coloring agent, and the like. The content of the thermoplastic resin in the transparent protective film is preferably 50 to 100% by weight, more preferably 50 to 99% by weight, further preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. . When the content of the thermoplastic resin in the transparent protective film is 50% by weight or less, high transparency or the like inherent to the thermoplastic resin may not be sufficiently exhibited.

  As the protective film, a retardation film, a brightness enhancement film, a diffusion film and the like can also be used.

  A functional layer such as a hard coat layer, an anti-reflection layer, an anti-sticking layer, a diffusion layer or an anti-glare layer can be provided on the surface of the protective film on which the polarizer is not adhered. The functional layers such as the hard coat layer, the antireflection layer, the antisticking layer, the diffusion layer and the antiglare layer can be provided on the transparent protective film itself, or separately provided separately from the transparent protective film. You can also.

(Intervening layer)
The protective film and the polarizer are laminated via an intervening layer such as an adhesive layer, a pressure-sensitive adhesive layer, and an undercoat layer (primer layer). At this time, it is preferable that both layers are laminated without an air gap by the intervening layer.
The adhesive layer is formed by an adhesive. The type of the adhesive is not particularly limited, and various adhesives can be used. The adhesive layer is not particularly limited as long as it is optically transparent. Examples of the adhesive include water-based, solvent-based, hot-melt, and active energy ray-curable adhesives. Alternatively, an active energy ray-curable adhesive is suitable.
Examples of the water-based adhesive include an isocyanate-based adhesive, a polyvinyl alcohol-based adhesive, a gelatin-based adhesive, a vinyl-based latex-based adhesive, and an aqueous-based polyester. The water-based adhesive is usually used as an adhesive composed of an aqueous solution, and usually contains a solid content of 0.5 to 60% by weight.
The active energy ray-curable adhesive is an adhesive whose curing progresses with an active energy ray such as an electron beam or an ultraviolet ray (radical-curable or cationically-curable). Can be used. As the active energy ray-curable adhesive, for example, a photo-radical curable adhesive can be used. When a photo-radical curable active energy ray-curable adhesive is used as an ultraviolet curable adhesive, the adhesive contains a radical polymerizable compound and a photopolymerization initiator.

  In laminating the polarizer and the protective film, an easy-adhesion layer can be provided between the transparent protective film and the adhesive layer. The easy-adhesion layer can be formed of, for example, various resins having a polyester skeleton, polyether skeleton, polycarbonate skeleton, polyurethane skeleton, silicone, polyamide skeleton, polyimide skeleton, polyvinyl alcohol skeleton, and the like. These polymer resins can be used alone or in combination of two or more. Further, other additives may be added for forming the easy-adhesion layer. Specifically, stabilizers such as tackifiers, ultraviolet absorbers, antioxidants, and heat stabilizers may be used.

  The pressure-sensitive adhesive layer is formed from a pressure-sensitive adhesive. Various pressure-sensitive adhesives can be used as the pressure-sensitive adhesive, for example, a rubber-based pressure-sensitive adhesive, an acrylic-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, a vinylalkyl ether-based pressure-sensitive adhesive, a polyvinylpyrrolidone-based pressure-sensitive adhesive, An acrylamide-based pressure-sensitive adhesive, a cellulose-based pressure-sensitive adhesive, and the like can be given. An adhesive base polymer is selected according to the type of the adhesive. Among the above-mentioned pressure-sensitive adhesives, acrylic pressure-sensitive adhesives are preferably used because they are excellent in optical transparency, show appropriate wettability, cohesiveness and adhesive pressure-sensitive adhesive properties, and are excellent in weather resistance and heat resistance. You.

  The undercoat layer (primer layer) is formed to improve the adhesion between the polarizer and the protective film. The material constituting the primer layer is not particularly limited as long as it exhibits a certain degree of strong adhesion to both the base film and the polyvinyl alcohol-based resin layer. For example, a thermoplastic resin excellent in transparency, thermal stability, stretchability and the like is used. Examples of the thermoplastic resin include an acrylic resin, a polyolefin resin, a polyester resin, a polyvinyl alcohol resin, and a mixture thereof.

(Surface protection film)
The first and second surface protection films are provided on one surface (the surface on which the adhesive layer is not laminated) of the polarizing film in the optical film, and protect the optical functional film such as the polarizing film.
As the base film of the first and second surface protection films, a film material having or close to isotropic is selected from the viewpoints of testability and manageability. Examples of the film material include a polyester resin such as a polyethylene terephthalate film, a cellulose resin, an acetate resin, a polyether sulfone resin, a polycarbonate resin, a polyamide resin, a polyimide resin, a polyolefin resin, and an acrylic resin. A transparent polymer such as a resin can be used. Of these, polyester resins are preferred. The base film may be used as a laminate of one or more film materials, or a stretched product of the above film. The thickness of the base film is preferably 10 μm to 150 μm or less, more preferably 20 to 100 μm.

  As the first and second surface protection films, the above-mentioned base film can be used as a self-adhesive film, and those having the above-mentioned base film and pressure-sensitive adhesive layer can be used. As the first and second surface protective films, those having an adhesive layer are preferably used from the viewpoint of protecting an optical functional film such as a polarizing film.

  As the pressure-sensitive adhesive layer used for laminating the first and second surface protective films, for example, a (meth) acryl-based polymer, a silicone-based polymer, a polyester, a polyurethane, a polyamide, a polyether, a fluorine-based or rubber-based polymer, or the like can be used. An adhesive serving as a base polymer can be appropriately selected and used. From the viewpoints of transparency, weather resistance, heat resistance and the like, an acrylic pressure-sensitive adhesive containing an acrylic polymer as a base polymer is preferred. The thickness (dry film thickness) of the pressure-sensitive adhesive layer is determined according to the required pressure-sensitive adhesive strength. Usually, it is about 1 to 100 μm, preferably 5 to 50 μm.

  The first and second surface protection films may be provided with a release treatment layer on the surface opposite to the surface on which the pressure-sensitive adhesive layer is provided, using a low-adhesion material such as silicone treatment, long-chain alkyl treatment, or fluorine treatment. it can.

<Adhesive layer>
For forming the pressure-sensitive adhesive layers 12 and 22, an appropriate pressure-sensitive adhesive can be used, and the type thereof is not particularly limited. As the adhesive, a rubber-based adhesive, an acrylic-based adhesive, a silicone-based adhesive, a urethane-based adhesive, a vinylalkyl ether-based adhesive, a polyvinyl alcohol-based adhesive, a polyvinylpyrrolidone-based adhesive, a polyacrylamide-based adhesive, Cellulose-based adhesives and the like can be mentioned.

  Among these pressure-sensitive adhesives, those having excellent optical transparency, exhibiting appropriate wettability, cohesiveness and adhesive pressure-sensitive adhesive properties and having excellent weather resistance and heat resistance are preferably used. An acrylic pressure-sensitive adhesive is preferably used to exhibit such characteristics.

  Examples of the method for forming the pressure-sensitive adhesive layers 12 and 22 include, for example, a release film in which the pressure-sensitive adhesive is peeled off (applied to a separator or the like, and a polymerization solvent or the like is dried and removed to form a pressure-sensitive adhesive layer; (Or a transparent protective film), or a method in which the pressure-sensitive adhesive is applied to a polarizer (or a transparent protective film), and a polymerization solvent or the like is dried and removed to form a pressure-sensitive adhesive layer on the polarizer. In applying the pressure-sensitive adhesive, one or more solvents other than the polymerization solvent may be newly added as appropriate.

  As the release film subjected to the release treatment, a silicone release liner is preferably used. In the step of applying and drying the pressure-sensitive adhesive of the present invention on such a liner to form a pressure-sensitive adhesive layer, a method for drying the pressure-sensitive adhesive may be appropriately selected depending on the purpose. Preferably, a method of heating and drying the coating film is used. The heating and drying temperature is preferably from 40C to 200C, more preferably from 50C to 180C, and particularly preferably from 70C to 170C. By setting the heating temperature within the above range, a pressure-sensitive adhesive having excellent pressure-sensitive adhesive properties can be obtained.

As the drying time, an appropriate time can be appropriately used. The drying time is preferably from 5 seconds to 2 seconds.
0 minutes, more preferably 5 seconds to 10 minutes, particularly preferably 10 seconds to 5 minutes.

  Various methods are used for forming the first pressure-sensitive adhesive layers 12 and 22. Specifically, for example, by roll coat, kiss roll coat, gravure coat, reverse coat, roll brush, spray coat, dip roll coat, bar coat, knife coat, air knife coat, curtain coat, lip coat, die coater, etc. Examples include a method such as an extrusion coating method.

  The thickness of the first pressure-sensitive adhesive layers 12 and 22 is not particularly limited, and is, for example, about 1 to 100 μm. Preferably, it is 2 to 50 μm, more preferably 2 to 40 μm, and still more preferably 5 to 35 μm.

<Release film>
The first release films 11 and 21 protect the pressure-sensitive adhesive layer until it is put to practical use. Examples of the constituent material of the release film include plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films, porous materials such as paper, cloth, and nonwoven fabric, nets, foam sheets, metal foils, and laminates thereof. Although a suitable thin leaf body can be used, a plastic film is preferably used because of its excellent surface smoothness.

  The plastic film is not particularly limited as long as it can protect the pressure-sensitive adhesive layer. Examples of the plastic film include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, and vinyl chloride film. Examples include a polymer film, a polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, and an ethylene-vinyl acetate copolymer film.

  The thickness of the first release films 11 and 21 is usually about 5 to 200 μm, preferably about 5 to 100 μm. The separator, if necessary, a silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based release agent, release and antifouling treatment with silica powder, etc., coating type, kneading type, vapor deposition type For example, antistatic treatment such as antistatic treatment can also be performed. In particular, by appropriately performing a release treatment such as a silicone treatment, a long-chain alkyl treatment, or a fluorine treatment on the surface of the release film, the releasability from the pressure-sensitive adhesive layer can be further improved.

<Manufacture of optical film set>
Next, a method for manufacturing the first optical film set and the second optical film set will be described. FIG. 2A is a schematic view illustrating a method of manufacturing the first optical film 1 in a roll shape. FIG. 2B is a schematic view illustrating a method of manufacturing the sheet-shaped first optical film 2.

  In FIG. 2A, a roll-shaped first optical film raw material 5 having a configuration in which a first release film, a first pressure-sensitive adhesive layer, a first optical functional film, and a first surface protection film are laminated in this order is prepared. Next, the first optical film is unwound from the first optical film raw material 5, and slit into three strip-shaped optical films with a predetermined width a using the slit cut portion sc. The three strip-shaped optical films that have been subjected to the slit processing are each wound to produce a roll-shaped first optical film.

  In the present embodiment, the slit processing is performed on three strip-shaped optical films, but the present invention is not limited to this. In the present embodiment, both ends e1 and e2 are trimmed (end trimming), but either one end may be trimmed, or both ends may not be trimmed.

  In FIG. 2B, the second surface protection film 25 unwound from the second surface protection film raw S25 on the first surface protection film 14 side of the roll-shaped first optical film 1 (corresponding to the first optical film raw). Are laminated by a laminating means (a pair of laminating rolls R1 and R2) to produce a raw optical film S2 on which the second surface protection film 25 is laminated. Next, the optical film raw material S2 on which the second surface protection film 25 is laminated is completely cut at a predetermined interval b using the cutting means FC to manufacture the sheet-shaped first optical film 2. The sheet-shaped first optical film 2 may be housed in a predetermined housing section, or may be stacked on a carrier film. The first optical film set can be manufactured by the above method.

  As another embodiment, the step of winding the optical film raw material S2, the belt-shaped first optical film from the optical film raw material S2, and the cutting process at the predetermined interval b using the cutting means FC may be performed.

  Further, as another embodiment, after the slit processing, the pressure-sensitive adhesive layer 12, the first optical function film, and the first surface protection film are cut (half-cut) at predetermined intervals while leaving the strip-shaped first release film 11, The method may further include a step of forming a plurality of cuts.

(Liquid crystal cell, liquid crystal display panel)
The liquid crystal cell has a configuration in which a liquid crystal layer is sealed between a pair of substrates (a first substrate (viewing side surface) Pa and a second substrate (back surface) Pb) disposed to face each other. Although any type of liquid crystal cell can be used, it is preferable to use a vertical alignment (VA) mode and an in-plane switching (IPS) mode liquid crystal cell in order to realize high contrast. The liquid crystal display panel is formed by attaching a polarizing film to one or both sides of a liquid crystal cell, and incorporates a drive circuit as needed.

(Organic EL cell, organic EL display panel)
The organic EL cell has a structure in which an electroluminescent layer is sandwiched between a pair of electrodes. As the organic EL cell, for example, an arbitrary type such as a top emission type, a bottom emission type, and a double emission type can be used. The organic EL display panel is obtained by attaching a polarizing film to one or both sides of an organic EL cell, and incorporates a drive circuit as needed.

<Reproduction using the first optical film set>
FIG. 3 is a schematic diagram of a continuous production system for an optical display panel. In this embodiment, the roll-shaped first optical film 1 is used for manufacturing an optical display panel by a roll-to-panel method. The sheet-shaped first optical film 2 is determined to be defective among the optical display panels manufactured using the roll-shaped first optical film 1, and the first pressure-sensitive adhesive layer, the first optical functional film, and the first An optical display panel having a configuration in which a first pressure-sensitive adhesive layer, a first optical functional film, and a first surface protection film are laminated in this order on one surface of an optical cell of the optical display panel from which the surface protection film has been peeled off is remanufactured. Used to do. Specifically, the first pressure-sensitive adhesive layer 22, the first optical function film 23, and the first surface protection film 24 are separated from each other on one surface of the optical cell by a sheet-to-panel method. After the first release film 21 is peeled from the film 2 and the first pressure-sensitive adhesive layer 22, the first optical function film 23, the first surface protection film 24, and the second surface protection film 25 are laminated in this order, The surface protection film 25 is peeled off. In the present embodiment, a liquid crystal cell will be described as an example of an optical cell, and a liquid crystal display panel will be described as an example of an optical display panel.

  The first optical film 1 in the form of a roll has a first release film 11, a first pressure-sensitive adhesive layer 12, a first optical functional film 13, and a first surface protection film 14 laminated in this order. As shown in FIG. 1, the roll-shaped first optical film 1 has a width a, and has a width corresponding to the long side of the liquid crystal panel (substantially shorter than the long side of the liquid crystal cell P).

  As shown in FIG. 3, the system for manufacturing a liquid crystal display panel according to the present embodiment includes a first transport unit 81 that transports a liquid crystal cell P to a first attaching unit 64, and a first surface P1 of the liquid crystal cell P in a roll shape. It has a second transport unit 82 that transports the liquid crystal cell P after the optical film is attached using the first optical film 1. Each transport unit is configured to have a plurality of transport rollers R for transporting the liquid crystal cell P by rotating about a rotation axis parallel to a direction orthogonal to the transport direction. In addition, it may be configured to include a suction plate in addition to the transport roller.

(Liquid crystal cell transport process)
The liquid crystal cell P is arranged from the storage section 91 for storing the liquid crystal cell P to the first transport section 81 such that the first surface P1 faces the top surface, and is transported to the first attaching section 64 by the rotation of the transport roller R. You.

(First optical film feeding step, first optical film cutting step)
The strip-shaped first optical film 10 unreeled from the roll-shaped first optical film 1 is left without cutting the first release film 11 at the cutting portion 61 while adsorbing and fixing the first release film 11 side. The band-shaped pressure-sensitive adhesive layer 12, the band-shaped first optical function film 13, and the band-shaped first surface protection film 14 have a predetermined size (a length corresponding to the short side of the liquid crystal cell P (a length substantially shorter than the short side). Cut) to form a cut portion s. The cutting by the cutting unit 61 includes, for example, cutting using a blade (cutting with a cutting blade) and cutting with a laser device. An example of the cut portion s after cutting is shown by an arrow in FIG. 3, but the cut is intentionally drawn large for ease of explanation. A configuration may be adopted in which a nip roller (not shown) is arranged on the upstream side or the downstream side of the cutting section 61 and conveys the band-shaped first optical film 10. Note that the nip rollers may be arranged on the upstream side and the downstream side of the cutting section 61.

(Tension adjustment step)
In the cutting process of the strip-shaped first optical film 10 and the subsequent attaching process, a first tension adjusting unit for enabling continuous processing so as not to be interrupted for a long time and adjusting slack of the film. 62 are provided. The first tension adjusting unit 62 is configured to have, for example, a dancer mechanism using a weight. A nip roller (not shown) may be arranged upstream or downstream of the first tension adjusting unit 62 to convey the first optical film 10. Note that the nip rollers may be arranged on the upstream side and the downstream side of the first tension adjusting unit 62.

(Peeling process)
The first optical film 10 is wound around the first peeling part 63 and turned over, and the first optical film 10 is peeled from the first release film 11. The first release film 11 is wound around a roll by the first winding unit 65. The first winding unit 65 has a roll and a rotation drive unit, and the rotation drive unit rotates the roll to wind the first release film 11 around the roll. Further, a configuration may be adopted in which a nip roller (not shown) is disposed on the upstream side or the downstream side of the peeling section 63 and transports the first optical film 10 or the first release film 11. Note that the nip rollers may be disposed on the upstream side and the downstream side of the peeling section 63.

(First sticking step)
The first affixing section 64 holds the first optical film 10 from which the first release film 11 has been peeled to the first surface P1 of the liquid crystal cell P while transporting the liquid crystal cell P via the first adhesive layer 12. And paste. The first attaching section 64 includes a pair of a first roller 64a and a second roller 64b. Either one may be a driving roller and the other may be a driven roller, or both rollers may be driving rollers. The first optical film 10 is attached to the first surface P1 of the liquid crystal cell P by being sent downstream while sandwiching the first optical film 10 and the liquid crystal cell P between the pair of first rollers 64a and the second roller 64b. The liquid crystal cell P after the sheet-like first optical film 10 is attached to the first surface P1 of the liquid crystal cell P is transported downstream by the second transport unit 82.

(First inspection process)
The first inspection unit 70 optically inspects the liquid crystal cell P. The first inspection unit 70 is disposed on one surface side of the liquid crystal cell P, and is disposed on a side opposite to the light source with the light source 71 transmitting light to the liquid crystal cell P interposed therebetween. It has a first imaging unit 72 that captures an optical image. The first imaging unit 72 may be an area sensor or a line sensor. Further, the first inspection unit 70 may include a second imaging unit (not shown) that captures a reflected light image for inspecting a position where the first optical film 10 is attached. The image captured by the first inspection unit 70 is analyzed by the first image analysis unit 51. The control unit 50 controls the operation timing and the like of each component of the continuous manufacturing system.

(First determination step)
The first determination unit 52 determines whether the liquid crystal cell P is non-defective or defective based on the result of analyzing the image by the first image analysis unit 51. Examples of defective products include misalignment and mixing of air bubbles. The liquid crystal cell P determined to be defective is collected by the first non-defective product collection unit 92. The liquid crystal cell P determined as a defective product is collected by the first defective product collection unit 93.

(First defective film peeling step)
The process of remanufacturing a defective liquid crystal panel into a non-defective liquid crystal panel will be described with reference to FIG. As shown in FIG. 4, the first optical film 10 is removed from the liquid crystal cell P for which the first determination unit 52 has determined a defective product. The removal treatment may be performed manually or may be performed by a peeling device. Next, it will be described that the sheet-like first optical film 2 is attached to the first surface P1 of the liquid crystal cell P and remanufactured (sometimes referred to as “rework”) using a sheet-by-sheet attaching apparatus.

(First re-pasting step)
Next, the sheet-shaped first optical film 2 from which the first release film 21 has been peeled off is peeled off by the sheet-to-panel method (for example, a single-wafer bonding apparatus), and the first optical film 10 determined to be defective is peeled off. Is adhered to the first surface P1 of the liquid crystal cell P after completion. A conventional device can be used as the sheet-feeding device. Reference is made to the sheet-shaped first optical film 2 of FIG.

(Second surface protection film peeling step)
After the first re-sticking step, the second surface protection film 25 is peeled off from the sheet-like first optical film 2. The peeling treatment may be performed manually or by a peeling device. Through the above steps, a liquid crystal panel having the same laminated structure as a liquid crystal panel manufactured by the roll-to-panel method can be manufactured (remanufactured).

  In the above embodiment, the optical film is adhered to one surface (first surface P1) of the liquid crystal cell by a roll-to-panel method, but is not limited thereto. An optical film may be attached to the other surface (second surface P2) of the liquid crystal cell by a roll-to-panel method.

  In the above embodiment, the first inspection step and the first determination step are performed after the first attaching step. However, after the optical film is attached to the other surface (second surface P2) of the liquid crystal cell, the inspection, A determination may be made. The optical film determined to be defective in the determination may be peeled from the liquid crystal cell, and may be adhered to the liquid crystal cell by a sheet-to-panel method using a sheet-like optical film.

(Modification)
In the present embodiment, the use of the optical film set of the roll-shaped optical film and the sheet-shaped optical film in the continuous manufacturing method of the liquid crystal display panel has been described. However, the present invention is not limited thereto. It may be used in a manufacturing method.

  In the embodiment, the above-described optical film is used as the roll-shaped optical film, but the configuration of the roll-shaped optical film is not limited thereto. For example, except for the release film, a roll of a strip-shaped optical film in which a plurality of cut lines are formed in the width direction (an optical film with a notch) may be used.

  In the embodiment, the strip-shaped optical film is cut at a predetermined interval in the width direction (half cut) .However, from the viewpoint of improving the yield, the strip-shaped optical film is cut in the width direction so as to avoid a defective portion of the strip-shaped optical film. The optical film including the defective portion may be cut to a size smaller than a predetermined interval (the size of the optical cell) (more preferably, to a size as small as possible).

  In the embodiment, the horizontally long rectangular liquid crystal cell and the liquid crystal display panel have been described as examples, but the shapes of the liquid crystal cell and the liquid crystal display panel have another pair of opposing sides and another pair of opposing sides. There is no particular limitation as long as it has a shape.

REFERENCE SIGNS LIST 1 roll-shaped optical film 11 release film 12 adhesive layer 13 optical function film 14 first surface protection film 2 sheet-like optical film 21 release film 22 adhesive layer 23 optical function film 24 first surface protection film 25 2 Surface protection film

Claims (14)

The optical film is removed from an optical display panel having an optical film in which an adhesive layer, an optical functional film, and a first surface protection film are laminated in this order, and an optical cell in which the optical film is provided on one surface. A method for manufacturing an optical display panel, wherein the one surface of the optical cell is re-attached to a sheet-shaped optical film having the same configuration as the removed optical film,
Release film, pressure-sensitive adhesive layer, optical functional film, first surface protection film and second surface protection film is peeled off from the sheet-shaped optical film laminated in this order, the release film, the pressure-sensitive adhesive layer A re-pasting step of pasting the sheet-like optical film to the one surface of the optical cell and re-manufacturing the optical display panel,
A second surface protection film removing step of removing the second surface protection film after the re-sticking step.   The method of manufacturing an optical display panel according to claim 1, further comprising a removing step of removing the optical film from the optical display panel based on a result of inspecting the optical cell to which the optical film is attached.   The method for manufacturing an optical display panel according to claim 1, further comprising an inspection step of inspecting the optical cell to which the optical film is attached. A release film, a pressure-sensitive adhesive layer, an optical function film, and a first surface protection film are laminated in this order. A cutting step of cutting leaving the release film in a direction orthogonal to the longitudinal direction of the optical film,
An attaching step of attaching the optical film from which the release film has been peeled off to the one surface of the optical cell via the pressure-sensitive adhesive layer, and further comprising: Manufacturing method of optical display panel.   A roll formed by winding an optical film having a release film, an adhesive layer, an optical functional film, and a first surface protection film laminated in this order and having cuts formed at predetermined intervals except for the release film. The optical film is unwound from the optical film, the release film is peeled off the optical film, the pasting step of attaching to the one surface of the optical cell through the adhesive layer, and further comprising: A method for manufacturing an optical display panel according to any one of the preceding claims. A roll-shaped optical film having a configuration in which a release film, an adhesive layer, an optical functional film, and a first surface protection film are laminated in this order;
A step of preparing an optical film set having a sheet-shaped optical film in which the release film, the pressure-sensitive adhesive layer, the optical functional film, the first surface protective film, and the second surface protective film are laminated in this order, The method for manufacturing an optical display panel according to claim 1, further comprising: A roll formed by winding an optical film having a release film, an adhesive layer, an optical functional film, and a first surface protection film laminated in this order and having cuts formed at predetermined intervals except for the release film. Optical film and
A step of preparing an optical film set having a sheet-like optical film in which the release film, the pressure-sensitive adhesive layer, the optical functional film, the first surface protection film, and the second surface protection film are laminated in this order, The method for manufacturing an optical display panel according to any one of claims 1 to 5, wherein the method includes: The optical film is removed from an optical display panel having an optical film in which an adhesive layer, an optical functional film, and a first surface protection film are laminated in this order, and an optical cell in which the optical film is provided on one surface. An optical display panel manufacturing system for re-attaching a sheet-shaped optical film having the same configuration as the removed optical film to the one surface of the optical cell,
The release film, the pressure-sensitive adhesive layer, the optical functional film, the first surface protection film and the second surface protection film are separated from the sheet-shaped optical film laminated in this order, and the release film is peeled off. A re-pasting unit for pasting the optical display panel by pasting the sheet-like optical film on the one surface of the optical cell via
An optical display panel manufacturing system, comprising: a second surface protection film removing unit that removes the second surface protection film after the processing of the re-sticking unit.   The method of manufacturing an optical display panel according to claim 8, further comprising an optical film removing unit that removes the optical film from the optical display panel based on a result of inspecting the optical cell to which the optical film is attached.   The optical display panel manufacturing system according to claim 8, further comprising an inspection unit configured to inspect the optical cell to which the optical film is attached. A release film, a pressure-sensitive adhesive layer, an optical function film, and a first surface protection film are laminated in this order. A cutting step of cutting leaving the release film in a direction orthogonal to the longitudinal direction of the optical film,
An attaching step of attaching the optical film, from which the release film has been peeled, to the one surface of the optical cell via the adhesive layer, further comprising: Optical display panel manufacturing system.   A roll formed by winding an optical film having a release film, an adhesive layer, an optical functional film, and a first surface protection film laminated in this order and having cuts formed at predetermined intervals except for the release film. The optical film, which is unwound from the optical film of the above, and the optical film from which the release film has been peeled off, further has a sticking portion for sticking to the one surface of the optical cell via the pressure-sensitive adhesive layer, further comprising: 2. The system for manufacturing an optical display panel according to claim 1. A roll-shaped optical film having a configuration in which a release film, an adhesive layer, an optical functional film, and a first surface protection film are laminated in this order;
A production unit for producing an optical film set having a sheet-shaped optical film in which a release film, an adhesive layer, an optical functional film, a first surface protection film, and a second surface protection film are laminated in this order; The optical display panel manufacturing system according to any one of claims 8 to 11, further comprising: A roll formed by winding an optical film having a release film, an adhesive layer, an optical functional film, and a first surface protection film laminated in this order and having cuts formed at predetermined intervals except for the release film. Optical film and
A release unit, a pressure-sensitive adhesive layer, an optical functional film, a first surface protection film and a second production unit for producing an optical film set having a sheet-like optical film having a configuration in which the second surface protection film is laminated in this order, The method for manufacturing an optical display panel according to claim 8, further comprising:

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