JP6792367B2 - Single-wafer optical film - Google Patents

Description

The present invention relates to a single-wafer optical film, for example, a single-wafer optical film used in a sheet-to-panel manufacturing facility.

An optical film in which a release film, an 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. The optical film unwound from this roll-shaped optical film is cut (half-cut) in the width direction of the adhesive layer, the optical functional film, and the surface protective film while leaving the release film, and the optical film obtained by cutting. There is a method (hereinafter, also referred to as "roll-to-panel method") in which the release film is peeled off from the mold release film and the optical film is attached 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 bonding method different from the roll-to-panel method, an optical film that has been made into a single-wafer state in advance is attached to an optical cell via an adhesive layer that is exposed by peeling off the release film. There is a matching method (hereinafter, also referred to as “seat-to-panel method”) (see, for example, Patent Document 3).

Japanese Unexamined Patent Publication No. 2011-123208 JP 2015-049115 Japanese Unexamined Patent Publication No. 2006-039238

By the way, at the manufacturing site of optical display panels such as liquid crystal display panels, there is a new case where not only the roll-to-panel method but also the sheet-to-panel method is used to manufacture optical display panels having the same configuration. It has occurred. For example, Patent Document 2 discloses that an optical display panel is continuously manufactured by using a roll-to-panel method, and an optical display panel determined to be defective is subjected to a rework process. When a large number of defective products are not generated, it is conceivable to use a sheet-to-panel method when attaching a new optical functional film to the optical cell in such a rework process. Also, for example, when it is necessary to mass-produce optical display panels with the same configuration in a short period of time, the roll-to-panel method cannot cover all the supply, and the sheet-to-panel method is used together. Is also possible.

In recent years, as optical display panels have become thinner, optical functional films (for example, polarizing films having a thickness of 60 μm or less) that are thinner than conventional films, such as polarizing films, are being developed. Such a thin optical functional film has a weak waist (elastic modulus) and is liable to be twisted or curled.

According to the roll-to-panel method, a thin optical functional film is conveyed to a bonding position in a state of being laminated on a carrier film (release film), and the carrier film (release film) has an optical function at the bonding position. Since the film is peeled off and the optical functional film is attached to the optical cell, it is possible to continuously attach the thin optical functional film to the optical cell while suppressing the occurrence of twisting and curling. However, in the sheet-to-panel method, it is difficult to handle the transfer of the single-wafered optical functional film, the peeling of the release film, the bonding process of the optical functional film to the liquid crystal cell, and the bonding failure occurs. There is concern that the yield will decline.

According to the present invention, when a thin optical functional film is bonded to an optical cell, an optical display panel having the same configuration can be suitably manufactured even if a roll-to-panel method and a sheet-to-panel method are used in combination. An object of the present invention is to provide a leaf-shaped optical film.

The present invention is a single-wafer optical film in which a release film, an adhesive layer, an optical functional film, a first surface protective film and a second surface protective film are laminated in this order.
The magnitude relationship of the peeling force between each layer in a single-wafer optical film is
Delamination force between the release film and the adhesive layer A,
Delamination force B between the adhesive layer and the optical functional film,
Delamination force between the optical functional film and the first surface protective film C,
When the delamination force D between the first surface protective film and the second surface protective film is set,
A <B, A <C, A <D.

In the above invention, the magnitude relationship of the peeling force is preferably A <D <C ≦ B or A <D <B ≦ C, and more preferably A <D <C <B.

In the above invention, the optical functional film may be a polarizing film.

In the above invention, the polarizing film may have a thickness of 60 μm or less.

In the above invention, the polarizing film may have a polarizer having a thickness of 10 μm or less.

In the above invention, the first surface protective film may have a first base film and a first pressure-sensitive adhesive layer, and may be laminated on the optical functional film via the first pressure-sensitive adhesive layer.

In the above invention, the first surface protective film may be a self-adhesive film.

In the above invention, the second surface protective film may have a second base film and a second pressure-sensitive adhesive layer, and may be laminated on the first surface protection film via the second pressure-sensitive adhesive layer. ..

In the above invention, the second surface protective film may be a self-adhesive film.

The single-wafer optical film of the present invention is used in a sheet-to-panel system. Since the single-wafer optical film provided with the second surface protective film has improved handleability, it uses a sheet-to-panel method to optical while suppressing the occurrence of twisting and curling. It can be suitably bonded to the cell. Then, by removing (for example, peeling) the second surface protective film from the sheet-fed optical film bonded to the optical display panel, the result is the same as 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 single-wafer optical film of the present invention, when the optical film is attached to the optical cell, even when the roll-to-panel method and the sheet-to-panel method are used in combination, the optics have the same configuration. The display panel can be suitably manufactured.

Schematic diagram showing the optical film set of the first embodiment Schematic diagram of roll-to-panel manufacturing system Schematic diagram of a seat-to-panel manufacturing system

<Single-wafer optical film>
First, a set of a sheet-fed optical film and a roll-shaped optical film used in the present invention will be described. FIG. 1 is a schematic view showing a single-wafer-shaped optical film and a roll-shaped optical film. The side surface, the plane, and a partial cross-sectional enlarged view of the roll-shaped first optical film 1 are shown in the upper part of FIG. The lower part of FIG. 1 shows a side surface, a plane, and a partially enlarged cross-sectional view of the single-wafered first optical film 2. In the roll-shaped first optical film 1, the first release film 11, the first adhesive layer 12, the first optical functional film 13, and the first surface protective film 14 are 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, which is unwound from the roll-shaped first optical film 1, is cut by the cutting means C at a predetermined interval b, leaving the release film 11. Reference numeral s is a notch formed in the first optical film 10 by the above-mentioned cutting.

Further, in the single-wafer-shaped first optical film 2, the first release film 21, the first adhesive layer 22, the first optical functional film 23, the first surface protective film 24, and the second surface protective film 25 are laminated in this order. Has been done. The size of the single-wafered first optical film 2 is vertical a and horizontal b. The single-wafered 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 functional film 13 and the first optical functional film 23 have the same configuration. The first surface protective film 14, the first surface protective film 24, and the second surface protective film 25 have the same configuration. The “same structure” may be defined as not only the materials, thicknesses, etc. are exactly the same, but also substantially the same (for example, the same in terms of manufacturing quality).

In the present embodiment, the first surface protective 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 provided via the first pressure-sensitive adhesive layer. ) Is laminated. In addition, as another embodiment, the first surface protection film 14 (or 24) may be a self-adhesive type film.

In the present embodiment, the second surface protective film 25 has a second base 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. As another embodiment, the second surface protective film 25 may be a self-adhesive film.

(Relationship between interphase peeling force)
Further, the peeling force between the layers of the first surface protective film 24 and the first optical functional film 23 is larger than the peeling force between the layers of the second surface protective film 25 and the first surface protective film 24. According to this, the second surface protective film 25 can be peeled off more smoothly. As the peeling force, for example, a tensile tester can be used. The peeling condition is measured at 180 ° peeling of 0.3 m / min. The peeling force is controlled by the composition and thickness of the adhesive.

The magnitude relationship of the peeling force between the layers of the single-wafered first optical film 2 is as follows.
Delamination force A between the first release film 21 and the first adhesive layer 22
Delamination force B between the first pressure-sensitive adhesive layer 22 and the first optical functional film 23,
Delamination force C between the first optical functional film 23 and the first surface protective film 24,
When the delamination force D between the first surface protective film 24 and the second surface protective film 25 is set,
A <B, A <C, A <D.
Preferably, A <D <C ≦ B or A <D <B ≦ C.
More preferably, A <D <C <B.
According to the relationship of the interphase peeling force described above, it is possible to prevent the second surface protective film from being peeled off when the first release film is peeled off.

<Optical functional 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 improving film, and a diffusion film, but a polarizing film is typical. ..

(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 further preferably 50 μm or less. As the polarizing film, for example, (1) a configuration in which protective films (sometimes referred to as “polarizer protective films”) are laminated on both sides of the polarizing element (sometimes referred to as “both protective polarizing films”). , (2) A configuration in which a protective film is laminated only on one side of the polarizer (sometimes referred to as a "single protective polarizing film") and the like can be mentioned.

(Polarizer)
As the polarizer, one using a polyvinyl alcohol-based resin is used. As the polarizer, for example, a hydrophilic polymer film such as a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, an ethylene-vinyl acetate copolymerization system partially saponified film, and a bicolor property of iodine or a bicolor dye are used. Examples thereof include a uniaxially stretched film by adsorbing a substance, a polyene-based oriented film such as a dehydrated product of polyvinyl alcohol and a dehydrogenated product of polyvinyl chloride. Among these, a polarizer made 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 it can be produced, for example, by dyeing polyvinyl alcohol by immersing it in an aqueous solution of iodine and stretching it 3 to 7 times its original length. If necessary, boric acid, zinc sulfate, zinc chloride and the like may be contained, or the mixture 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. In addition to being able to clean the surface of the polyvinyl alcohol film and blocking inhibitors by washing the polyvinyl alcohol film with water, it also has the effect of preventing non-uniformity such as uneven dyeing by swelling the polyvinyl alcohol film. is there. Stretching may be performed after dyeing with iodine, stretching while dyeing, or stretching and then dyeing with iodine. It can be stretched even in an aqueous solution such as 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 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 polarizing element has less uneven thickness, excellent visibility, and less dimensional change, so that it has excellent durability against thermal shock. On the other hand, in a polarizing film containing a polarizer having a thickness of 10 μm or less, the waist (elastic modulus) of the film is remarkably low, so that there is a high possibility that twisting, curling, etc. will occur in the sheet-to-panel method. Therefore, the present invention is particularly suitable for the polarizing film.

As a thin polarizer, typically
Japanese Patent No. 4751486,
Japanese Patent No. 4751481
Patent No. 4815544,
Japanese Patent No. 5048120,
International Publication No. 2014/07759 Pamphlet,
International Publication No. 2014/077636 Pamphlet,
Etc., or the thin polarizing element obtained from the manufacturing method described in these.

The polarizer has optical characteristics represented by a simple substance transmittance T and a degree of polarization P of the following equation P> − (10 ^0.929 T ^-42.4 -1) × 100 (where T <42.3). Or,
P ≧ 99.9 (however, T ≧ 42.3)
It is preferable that the configuration is such that the above conditions are satisfied. A polarizer configured to satisfy the above conditions primarily has the performance required for a display for a liquid crystal television using a large display element. Specifically, the contrast ratio is 1000: 1 or more and the maximum brightness is 500 cd / m ² or more. As another use, for example, it is attached to the visible side of an organic EL cell.

The thin polarizer is patented in Patent No. 4751486, in that it can be stretched at a high magnification and the polarization performance can be improved even in a manufacturing method including a step of stretching in a laminated state and a step of dyeing. Those obtained by a production method including a step of stretching in an aqueous boric acid solution as described in Japanese Patent No. 4751481 and Japanese Patent No. 4815544 are preferable, and particularly described in Japanese Patent No. 4751481 and Japanese Patent No. 4815544. It is preferably obtained by a production method including a step of auxiliary stretching in the air before stretching in a certain boric acid aqueous solution. These thin polarizers can be obtained by a production method including a step of stretching a polyvinyl alcohol-based resin (hereinafter, also referred to as PVA-based resin) layer and a resin base material for stretching in a laminated state and a step of dyeing. With this manufacturing method, even if the PVA-based resin layer is thin, it can be stretched without problems such as breakage due to stretching because it is supported by the stretching resin base material.

(Protective film (polarizer protective film))
As the material constituting the protective film, those having excellent transparency, mechanical strength, thermal stability, moisture blocking property, isotropic property and the like are 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, and styrene such as polystyrene and acrylonitrile-styrene copolymer (AS resin). Examples thereof include based polymers and polycarbonate polymers. In addition, polyethylene, polypropylene, polyolefins having a cyclo or norbornene structure, polyolefin polymers such as ethylene / propylene copolymers, vinyl chloride polymers, amide polymers such as nylon and aromatic polyamides, imide polymers, and sulfone polymers. , Polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, allylate polymer, polyoxymethylene polymer, epoxy polymer, or the above. Polymer blends and the like are also examples of polymers that form the protective film.

In addition, one or more kinds of arbitrary suitable additives may be contained in a protective film. Examples of the additive include an ultraviolet absorber, an antioxidant, a lubricant, a plasticizer, a mold release agent, a color inhibitor, a flame retardant, a nucleating agent, an antistatic agent, a pigment, a colorant 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, still more 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, the high transparency inherent in the thermoplastic resin may not be sufficiently exhibited.

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

A functional layer such as a hard coat layer, an antireflection layer, a sticking prevention layer, a diffusion layer or an antiglare layer can be provided on the surface of the protective film to which the polarizer is not adhered. The functional layers such as the hard coat layer, the antireflection layer, the sticking prevention layer, the diffusion layer and the antiglare layer can be provided on the transparent protective film itself, and are separately provided separately from the transparent protective film. You can also do it.

(Intervening layer)
The protective film and the polarizer are laminated via an intervening layer such as an adhesive layer, an adhesive layer, and an undercoat layer (primer layer). At this time, it is desirable that both are laminated without an air gap by an intervening layer.
The adhesive layer is formed by the adhesive. The type of 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, and various forms such as water-based, solvent-based, hot-melt-based, and active energy ray-curable type are used as the adhesive. Alternatively, an active energy ray-curable adhesive is suitable.
Examples of the water-based adhesive include isocyanate-based adhesives, polyvinyl alcohol-based adhesives, gelatin-based adhesives, vinyl-based latex-based adhesives, and water-based polyesters. The water-based adhesive is usually used as an adhesive composed of an aqueous solution, and usually contains 0.5 to 60% by weight of a solid content.
The active energy ray-curable adhesive is an adhesive whose curing proceeds by active energy rays such as electron beam and ultraviolet rays (radical curing type, cationic curing type). For example, in the form of electron beam curing type and ultraviolet curing type. Can be used. As the active energy ray-curable adhesive, for example, a photoradical curable adhesive can be used. When a photoradical-curable active energy ray-curable adhesive is used as an ultraviolet curable type, the adhesive contains a radical-polymerizable compound and a photopolymerization initiator.

When 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, a polyether skeleton, a polycarbonate skeleton, a polyurethane skeleton, a silicone-based, a polyamide skeleton, a polyimide skeleton, a polyvinyl alcohol skeleton, and the like. These polymer resins may be used alone or in combination of two or more. Further, other additives may be added to form the easy-adhesion layer. Specifically, a tackifier, an ultraviolet absorber, an antioxidant, a stabilizer such as a heat-resistant stabilizer, or the like may be used.

The pressure-sensitive adhesive layer is formed from the pressure-sensitive adhesive. Various adhesives can be used as the adhesive, for example, rubber adhesive, acrylic adhesive, silicone adhesive, urethane adhesive, vinyl alkyl ether adhesive, polyvinylpyrrolidone adhesive, poly. Examples include acrylamide-based adhesives and cellulose-based adhesives. A sticky base polymer is selected according to the type of the pressure-sensitive adhesive. Among the above-mentioned pressure-sensitive adhesives, acrylic pressure-sensitive adhesives are preferably used because they are excellent in optical transparency, exhibit appropriate wettability, cohesiveness, and adhesiveness, and are excellent in weather resistance and heat resistance. To.

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 is a material that exhibits a certain degree of strong adhesion to both the base film and the polyvinyl alcohol-based resin layer. For example, a thermoplastic resin having excellent transparency, thermal stability, stretchability, etc. is used. Examples of the thermoplastic resin include acrylic resins, polyolefin resins, polyester resins, polyvinyl alcohol resins, and mixtures thereof.

(Surface protection film)
The first and second surface protective films are provided on one side of the polarizing film (the side on which the adhesive layer is not laminated) 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 protective films, a film material having isotropic or nearly isotropic is selected from the viewpoint of inspectability and controllability. Examples of the film material include polyester resins such as polyethylene terephthalate films, cellulose resins, acetate resins, polyether sulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, and acrylic resins. Examples include transparent polymers such as resins. Of these, polyester-based resins are preferable. The base film can be used as a laminate of one or more film materials, or a stretched product of the film can also be used. Base film The thickness of the film is preferably 10 μm to 150 μm or less, and more preferably 20 to 100 μm.

As the first and second surface protective films, the base film can be used as a self-adhesive type film, and those having the base film and the 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.

Examples of the pressure-sensitive adhesive layer used for laminating the first and second surface protective films include (meth) acrylic polymers, silicone-based polymers, polyesters, polyurethanes, polyamides, polyethers, fluorine-based polymers, and rubber-based polymers. The pressure-sensitive adhesive used as the base polymer can be appropriately selected and used. From the viewpoint of transparency, weather resistance, heat resistance and the like, an acrylic pressure-sensitive adhesive using an acrylic polymer as a base polymer is preferable. The thickness of the pressure-sensitive adhesive layer (dry film thickness) is determined according to the required adhesive strength. It is usually about 1 to 100 μm, preferably 5 to 50 μm.

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

<Adhesive layer>
An appropriate pressure-sensitive adhesive can be used for forming the pressure-sensitive adhesive layers 12 and 22, and the type thereof is not particularly limited. As adhesives, rubber adhesives, acrylic adhesives, silicone adhesives, urethane adhesives, vinyl alkyl ether adhesives, polyvinyl alcohol adhesives, polyvinylpyrrolidone adhesives, polyacrylamide adhesives, Examples include cellulose-based adhesives.

Among these adhesives, those having excellent optical transparency, exhibiting appropriate wettability, cohesiveness and adhesiveness, and excellent weather resistance and heat resistance are preferably used. Acrylic adhesives are preferably used to exhibit such characteristics.

As a method for forming the pressure-sensitive adhesive layers 12 and 22, for example, a release film (applied to a separator or the like, a polymerization solvent or the like is dried and removed to form a pressure-sensitive adhesive layer, and then a polarizer It is produced by a method of transferring to (or a transparent protective film), or a method of applying the adhesive to a polarizer (or a transparent protective film) and drying and removing a polymerization solvent or the like to form an adhesive layer on the polarizer. When applying the pressure-sensitive adhesive, one or more solvents other than the polymerization solvent may be newly added as appropriate.

A silicone release liner is preferably used as the release film that has been peeled off. In the step of applying the pressure-sensitive adhesive of the present invention on such a liner and drying it to form a pressure-sensitive adhesive layer, as a method of drying the pressure-sensitive adhesive, an appropriate method can be appropriately adopted depending on the purpose. Preferably, a method of overheating and drying the coating film is used. The heating and drying temperature is preferably 40 ° C. to 200 ° C., more preferably 50 ° C. to 180 ° C., and particularly preferably 70 ° C. to 170 ° C. By setting the heating temperature in the above range, a pressure-sensitive adhesive having excellent adhesive properties can be obtained.

As the drying time, an appropriate time can be adopted as appropriate. The drying time is preferably 5 seconds to 2 seconds.
It is 0 minutes, more preferably 5 seconds to 10 minutes, and particularly preferably 10 seconds to 5 minutes.

Various methods are used as the method for forming the first pressure-sensitive adhesive layers 12 and 22. Specifically, for example, 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. It is preferably 2 to 50 μm, more preferably 2 to 40 μm, and even more preferably 5 to 35 μm.

<Release film>
The first release films 11 and 21 protect the pressure-sensitive adhesive layer until they are put into practical use. Examples of the constituent materials of the release film include plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films, porous materials such as paper, cloth, and non-woven fabrics, nets, foam sheets, metal foils, and laminates thereof. An appropriate thin leaf body can be mentioned, but 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, and for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, and vinyl chloride are all used. Examples thereof include polymer films, polyethylene terephthalate films, polybutylene terephthalate films, polyurethane films, and ethylene-vinyl acetate copolymer films.

The thickness of the first release films 11 and 21 is usually about 5 to 200 μm, preferably about 5 to 100 μm. If necessary, the separator may be used for mold release and antifouling treatment with a silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based mold release agent, silica powder, etc., as well as a coating type, a kneading type, and a vapor deposition type. It is also possible to perform antistatic treatment such as. In particular, the peelability from the pressure-sensitive adhesive layer can be further enhanced by appropriately performing a peeling treatment such as a silicone treatment, a long-chain alkyl treatment, or a fluorine treatment on the surface of the release film.

(Liquid crystal cell, LCD display panel)
The liquid crystal cell has a configuration in which a liquid crystal layer is sealed between a pair of substrates (first substrate (visual side surface) Pa, second substrate (back surface) Pb) arranged to face each other. Any type of liquid crystal cell can be used, but in order to realize high contrast, it is preferable to use a liquid crystal cell in vertical orientation (VA) mode or in-plane switching (IPS) mode. The liquid crystal display panel is formed by laminating a polarizing film on one side or both sides of a liquid crystal cell, and a drive circuit is incorporated as needed.

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

(Roll-to-panel manufacturing system)
FIG. 2 shows a roll-to-panel type optical display panel manufacturing system using a roll-shaped first optical film 1. In the present embodiment, a liquid crystal cell as the optical cell and a liquid crystal display panel as the optical display panel will be described as an example.

In the roll-shaped first optical film 1, the first release film 11, the first adhesive layer 12, the first optical functional film 13, and the first surface protective film 14 are 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 (a width substantially shorter than the long side of the liquid crystal cell P).

As shown in FIG. 2, the liquid crystal display panel manufacturing system according to the present embodiment has a roll-like shape on the first transport unit 81 that transports the liquid crystal cell P to the first sticking portion 64 and the first surface P1 of the liquid crystal cell P. 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 around a rotation axis parallel to the direction orthogonal to the transport direction. In addition to the transport roller, a suction plate or the like may be provided.

(Liquid crystal cell transfer process)
From the storage unit 91 that stores the liquid crystal cell P, the liquid crystal cell P is arranged in the first transport unit 81 so that the first surface P1 faces the top surface, and is transported to the first sticking portion 64 by the rotation of the transport roller R. The liquid crystal.

(1st optical film feeding process, 1st optical film cutting process)
The band-shaped first optical film 10 unwound from the roll-shaped first optical film 1 retains and fixes the first release film 11 side, while leaving the first release film 11 uncut at the cutting portion 61. The band-shaped adhesive layer 12, the band-shaped first optical functional film 13, and the band-shaped first surface protective film 14 are provided in a predetermined size (length corresponding to the short side of the liquid crystal cell P (substantially shorter than the short side). S)) to form a notch s. Examples of the cutting by the cutting portion 61 include cutting using a cutting tool (cutting with a cutting tool) and cutting with a laser device. An example of the cut portion s after being cut is shown by an arrow in FIG. 2, but the cut is intentionally drawn large for ease of explanation. A nip roller (not shown) may be arranged on the upstream side or the downstream side of the cutting portion 61 to convey the strip-shaped first optical film 10. The nip rollers may be arranged on the upstream side and the downstream side of the cutting portion 61.

(Tension adjustment process)
In the cutting process of the strip-shaped first optical film 10 and the pasting process in the subsequent stage, the first tension adjusting unit is used to enable continuous processing so that the processing is not interrupted for a long time and to adjust the slack of the film. 62 is 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 on the upstream side or the downstream side of the first tension adjusting portion 62 to convey the first optical film 10. The nip rollers may be arranged on the upstream side and the downstream side of the first tension adjusting portion 62.

(Peeling process)
The first optical film 10 is wound around the first release portion 63 and inverted, and the first optical film 10 is peeled from the first release film 11. The first release film 11 is wound on a roll by the first winding unit 65. The first take-up 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 nip roller (not shown) may be arranged on the upstream side or the downstream side of the peeling portion 63 to convey the first optical film 10 or the first release film 11. The nip rollers may be arranged on the upstream side and the downstream side of the peeling portion 63.

(1st pasting process)
While transporting the liquid crystal cell P, the first sticking portion 64 attaches the first optical film 10 from which the first release film 11 has been peeled off to the first surface P1 of the liquid crystal cell P via the first adhesive layer 12. And paste. The first sticking portion 64 is composed of a pair of first rollers 64a and second rollers 64b. Either one may be a drive roller and the other may be a driven roller, and both rollers may be drive rollers. The first optical film 10 is attached to the first surface P1 of the liquid crystal cell P by feeding the first optical film 10 and the liquid crystal cell P 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-fed 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.

(Seat-to-panel manufacturing system)
FIG. 3 shows a sheet-to-panel type optical display panel manufacturing system using the sheet-fed first optical film 2. In the present embodiment, a liquid crystal cell as the optical cell and a liquid crystal display panel as the optical display panel will be described as an example.

In the single-wafer-shaped first optical film 2, the first release film 21, the first adhesive layer 22, the first optical functional film 23, the first surface protective film 24, and the second surface protective film are laminated in this order. .. As shown in FIG. 1, the single-wafer-shaped first optical film 2 has a length a and a width b, and has a width corresponding to the long side of the liquid crystal panel (a width substantially shorter than the long side of the liquid crystal cell P). ..

As shown in FIG. 3, the liquid crystal display panel manufacturing system according to the present embodiment has a third transport unit 181 and a liquid crystal cell P that transport the liquid crystal cell P to the sheet-fed sticking device 164 (corresponding to the second sticking portion). It has a fourth transport unit 182 that transports the liquid crystal cell P after the optical film is attached to the first surface P1 of the sheet using the single-wafer-shaped first optical film 2. Each transport unit is configured to have a plurality of transport rollers R for transporting the liquid crystal cell P by rotating around a rotation axis parallel to the direction orthogonal to the transport direction. In addition to the transport roller, a suction plate or the like may be provided.

(Liquid crystal cell transfer process)
From the storage unit 191 that stores the liquid crystal cell P, the liquid crystal cell P is arranged in the third transport unit 181 so that the first surface P1 faces the top surface, and is transported to the sheet-fed sticking device 164 by the rotation of the transport roller R. The liquid crystal.

From the container 100 containing the single-wafer-shaped first optical film 2, the single-wafer-shaped first optical film 2 is adsorbed by the suction portion 164a of the single-wafer pasting device 164 and supplied to the laminating position. The first release film 21 is peeled from the single-wafered first optical film 2 by a peeling means. The suction surface of the suction portion 164a has an arcuate cross section. As the peeling means, for example, the first release film 21 may be peeled off by sticking the adhesive tape to the surface of the first release film 21 using an adhesive tape and moving the adhesive tape by a moving mechanism.

The sheet-fed sticking device 164 has a fixing surface 164b, and the fixing surface 164b adsorbs and fixes the first surface P1 side of the liquid crystal cell P. The sheet-fed second optical film 2 in a state where the first release film 21 is peeled off and the first pressure-sensitive adhesive layer 22 is exposed is attached to the first surface P1 of the liquid crystal cell P by rolling the suction portion 164a.

(Second surface protective film peeling step)
After the single-wafer-shaped first optical film 2 is attached, the second surface protective film 25 is peeled off. The peeling process may be performed manually or with a peeling device.

In the roll-to-panel manufacturing system (FIG. 2), the optical film is attached to one surface (first surface P1) of the liquid crystal cell by the roll-to-panel method, but the present invention is not limited to this. The optical film may be attached to the other surface (second surface P2) of the liquid crystal cell by a roll-to-panel method or a sheet-to-panel method.

In the sheet-to-panel manufacturing system (FIG. 3), the optical film is attached to one surface (first surface P1) of the liquid crystal cell by the sheet-to-panel method, but the present invention is not limited to this. The optical film may be attached to the other surface (second surface P2) of the liquid crystal cell by a roll-to-panel method or a sheet-to-panel method.

In the roll-to-panel method and sheet-to-panel method manufacturing system described above, an optical inspection may be performed after the optical film is attached to either one side or both sides. Depending on the result of the optical inspection (for example, when a defective product is determined), the optical film is removed from the liquid crystal cell (optical cell), and the optical cell is replaced again by the second panel manufacturing unit (sheet-to-panel method). The liquid crystal display panel (optical display panel) may be remanufactured by pasting.

(Modification example)
In the present embodiment, it has been described that the optical film set of the roll-shaped optical film and the single-wafer-shaped optical film is used in the continuous manufacturing method of the liquid crystal display panel, but the present invention is not limited to this, and the continuous organic EL display panel is used. It may be used in the manufacturing method.

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

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

In the embodiment, a horizontally long rectangular liquid crystal cell and a liquid crystal display panel have been described as an example, but the shape of the liquid crystal cell and the liquid crystal display panel has another set of opposite sides and another set of opposite sides. As long as it has a shape, it is not particularly limited.

1 Roll-shaped optical film 11 Release film 12 Adhesive layer 13 Optical functional film 14 1st surface protective film 2 Single-leaf optical film 21 Release film 22 Adhesive layer 23 Optical functional film 24 1st surface protective film 25 2 Surface protective film

Claims (4)

A sheet-fed optical film in which a release film, an adhesive layer, an optical functional film, a first surface protective film and a second surface protective film are laminated in this order.
The first surface protective film has an adhesive layer or is a self-adhesive type.
The second surface protective film has an adhesive layer or is a self-adhesive type.
The first surface protective film and the second surface protective film have the same configuration.
The magnitude relation of the peeling force between each layer in the sheet-fed optical film is the delamination force A between the release film and the pressure-sensitive adhesive layer, the delamination force B between the pressure-sensitive adhesive layer and the optical functional film, and the optical functional film and the first When the delamination force C with the surface protective film and the delamination force D between the first surface protective film and the second surface protective film are defined, A <D <C <B.
The optical functional film is a polarizing film having a thickness of 60 μm or less, and the polarizing film has a polarizer having a thickness of 10 μm or less.
The thickness of the first surface protective film is 10 μm to 150 μm.
The thickness of the second surface protective film is 10 μm to 150 μm.
Single-wafer optical film. The first aspect of the present invention is characterized in that the first surface protective film has a first base film and a first pressure-sensitive adhesive layer, and is laminated on the optical functional film via the first pressure-sensitive adhesive layer. The single-wafer optical film described. The claim is characterized in that the second surface protective film has a second base film and a second pressure-sensitive adhesive layer, and is laminated on the first surface protection film via the second pressure-sensitive adhesive layer. The sheet-fed optical film according to 1 or 2. Claim 1 that the material of the first surface protective film and the material of the second surface protective film are the same, and the thickness of the first surface protective film and the thickness of the second surface protective film are the same. The sheet-fed optical film according to any one of 1 to 3.

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