TW201901203A - Optical film with double-sided adhesive attached, and image display device - Google Patents

Abstract

The optical film (50) with an adhesive is provided with a first adhesive layer (21) on a first main surface of an optical film (11) having a first main surface and a second main surface, and a second main surface of the optical film A second adhesive layer (22) is provided on the surface. On the first main surface of the optical film, there is a non-adhesive region (2x) where the first adhesive layer is not provided and the optical film is exposed, and a bonding region where the first adhesive layer is attached to the optical film. The non-adhesion region is provided along the peripheral edge of the optical film, for example.

Description

Optical film with double-sided adhesive and image display device

The present invention relates to an optical film with an adhesive agent having an adhesive layer on both sides of the optical film, and an image display device.

Liquid crystal display devices or organic EL (Electroluminescence) display devices are widely used as various image display devices such as mobile phones, smart phones, car navigation devices, monitors, and televisions. The liquid crystal display device has a polarizing plate disposed on the visible side surface of the liquid crystal cell due to its display principle. In self-emitting display devices such as organic EL, there is no need to provide a polarizing plate in terms of the principle of image display. A case where a circular polarizing plate (a laminated body of a polarizing plate and a 1/4 wavelength plate) is arranged on the visible side surface.

Image display devices in which a front surface transparent member such as a touch sensor or a cover glass is provided on the surface of an image display panel are spreading, and this configuration is becoming mainstream in mobile use or vehicle use. By bonding the polarizing plate and the transparent member on the front surface through the adhesive layer, the refractive index difference at the interface is reduced, and the decrease in visibility due to reflection or scattering can be suppressed. In order to form such an image display device, it has been proposed to use an adhesive layer provided on one side of a polarizing plate for bonding to an image display unit and having an adhesive layer for bonding to a front surface transparent plate on the other side. A film with an adhesive on both sides (for example, refer to Patent Document 1). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2014-115468

[Problems to be solved by the invention]

Various demands have been made for narrower marginalization of display devices, and wiring routing around the screen or configuration of flexible printed wiring boards has been studied. On the other hand, there is a tendency that the space at the end of the screen that uses a cover glass having a curved shape portion or a component that can accommodate an image display device, such as a housing, is gradually limited.

The present invention provides an image display device capable of securing a storage space constituting a component, and an optical film with an adhesive used for the image display device. [Technical means to solve the problem]

The optical film with an adhesive of the present invention is provided with an adhesive layer on both sides of an optical film such as a polarizing plate. On at least one side of the optical film, there is a non-adhesive region where the adhesive film is not provided locally and the optical film is exposed. When the double-sided optical film with an adhesive is bonded to the image display panel and the transparent member on the front surface, the non-adhesive region becomes a gap. The structural components of an image display device such as an electrical connection member with a flexible printed wiring board (FPC), a curved portion of a housing or a front transparent plate, a resin material, or a conductive material are arranged in the gap. , Can effectively use space.

The double-sided adhesive-attached optical film of the present invention includes an optical film such as a polarizing plate, a first adhesive layer provided on a first main surface of the optical film, and a second adhesive provided on a second main surface of the optical film.剂 层。 The agent layer. On the first main surface of the optical film, there is a non-adhesive region where the first adhesive layer is not provided. In an image display device, an optical film and a front surface transparent member or an image display unit are bonded via a first adhesive layer, and a gap is formed in a non-adhesive region where the first adhesive layer is not provided. By disposing a printed wiring board, a front surface transparent member, a case, a conductive paste, a resin material, and the like in the gap, space can be effectively used, and narrowing and miniaturization can be achieved.

[First embodiment] <Optical film with adhesive> The double-sided optical film with adhesive in the first embodiment is optically provided along the periphery of the first main surface of the optical film without a first adhesive layer. A region where the film is exposed (non-adhesive region), and a region where the first adhesive layer is attached to the optical film (adhesive region).

FIG. 1A is a plan view of a first main surface side of a double-sided adhesive-attached optical film 51 according to an embodiment, and FIG. 1B is a cross-sectional view taken along line B1-B2. The optical film 51 with double-sided adhesive is provided with a first adhesive layer 21 on one main surface of the optical film 11 and a second adhesive layer 22 on the other main surface.

(Optical Film) As the optical film 11, for example, a polarizing plate is used. In a general polarizing plate, an appropriate transparent protective film is provided on one or both sides of the polarizing element as needed. As the polarizing element, for example, hydrophilicity such as adsorbing a dichroic substance such as iodine or a dichroic dye to a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, or an ethylene-vinyl acetate copolymer-based partially saponified film is used. A polymer film is formed by aligning a dichroic substance by stretching. As the transparent protective film provided on the surface of the polarizing element, transparency such as cellulose resin, cyclic polyolefin resin, acrylic resin, phenylmaleimide resin, and polycarbonate resin is preferably used. Material with excellent mechanical strength and thermal stability. As the transparent protective film of the polarizing element, an optically anisotropic film such as a retardation plate can also be used.

The optical film 11 may be formed by laminating a plurality of films through an appropriate adhesive layer or adhesive layer. Examples of the optical film other than the polarizing plate include a film for forming an image display device such as a retardation film, a viewing angle expanding film, a viewing angle limiting (anti-peeping) film, and a brightness enhancement film. A touch sensor or the like may also be provided in the optical film. In addition, a surface of the optical film may be provided with a hard coat layer, an anti-reflection layer, an anti-glare layer, an anti-adhesion layer, or the like, and a surface treatment may be performed for the purpose of improving adhesion.

(Adhesive layer) The first adhesive layer 21 provided on the first main surface of the optical film 11 and the second adhesive layer 22 provided on the second main surface of the optical film 11 preferably include optically transparent Adhesives. Either the first adhesive layer 21 or the second adhesive layer 22 is used for bonding the optical film 11 and the image display unit, and the other is used for the optical film 11 and a transparent member (covering a transparent plate such as glass) , Touch sensors, etc.).

As the adhesive constituting the adhesive layers 21 and 22, an acrylic polymer, a silicone polymer, a polyester, a polyurethane, a polyamide, a polyvinyl ether, and a vinyl acetate can be appropriately selected. / Vinyl chloride copolymer, modified polyolefin, epoxy-based, fluorine-based, natural rubber, synthetic rubber and other rubber-based polymers are used as the base polymer. In particular, an acrylic adhesive is preferably used when it is excellent in optical transparency, exhibits moderate wettability, cohesiveness, and adhesive properties such as adhesiveness, and is also excellent in weather resistance or heat resistance. The first adhesive layer 21 and the second adhesive layer 22 may also be formed by laminating a plurality of adhesive layers.

The adhesive constituting the first adhesive layer 21 and the second adhesive layer 22 may also be a light-curable adhesive that is hardened by light irradiation after being bonded to an adherend such as an image display unit or a transparent member on the front surface. For example, if a photocurable adhesive is used for bonding to a transparent member with a surface before a raised portion such as decorative printing, then the adhesive before the photocuring is bonded in a soft state to have step absorption, Therefore, it is possible to prevent air bubbles from being mixed into the vicinity of the raised portion. After bonding, UV (Ultraviolet, etc.) is irradiated to harden the adhesive, thereby improving the adhesion reliability. The photocurable adhesive is preferably, for example, a polymer, a monomer or oligomer having a photopolymerizable functional group, and a photopolymerization initiator. As the monomer or oligomer having a photopolymerizable functional group, a crosslinkable monomer having two or more polymerizable functional groups in one molecule may be used.

The thickness of the adhesive layers 21 and 22 is not particularly limited, but is generally about 5 to 500 μm. The thickness of the adhesive used for bonding the optical film 11 and the image display unit is preferably about 5 to 50 μm. The thickness of the adhesive used for bonding the optical film 11 and the transparent member on the front surface may be appropriately set according to the configuration of the transparent member on the front surface. For example, when the transparent member on the front surface has a raised portion caused by decorative printing or the like, in order to prevent bubbles from mixing into the periphery of the raised portion, it is preferable to set the thickness of the adhesive layer to 50 μm or more so that Step absorption.

(Non-adhesive region) In the double-sided adhesive-attached optical film 51 shown in FIG. 1, the first adhesive is provided along the periphery of three sides 11a ₂ , 11a _3, and 11a ₄ of the four sides of the optical film 11. Adhesive region of the agent layer 21. The first adhesive layer 21 is not provided on the optical film 11 along the periphery of the side 11 a ₁ extending in the y-direction. In the non-adhesion region 2x, the main surface of the optical film 11 is exposed, and a gap exists in the optical film 11.

The positions of the end face of the optical film 11 and the end face of the first adhesive layer 21 are aligned along the peripheral edges of the sides 11a ₂ , 11a _3, and 11a ₄ . Along the edges 11a ₁ in the region of the non-2x Next, the first adhesive layer 21 of the end surface 21e than the end surfaces 11e of the optical film 11 on the inner side. Such end faces 11e, 21e extending in parallel along the edges 11a ₁ in the y-direction.

The width W _{1 of the} non-adhesive region 2x, that is, the offset amount of the end surface 21e of the first adhesive layer 21 from the end surface 11e of the optical film 11 may be set according to the shape or size of a member provided in the non-adhesive region. From the viewpoint of effectively utilizing the periphery of the screen and the space in the vicinity thereof, W _{1 is} preferably 10 μm or more, more preferably 50 μm or more, and still more preferably 100 μm or more.

The upper limit of W ₁ is not particularly limited, as long as it is set according to the size of the image display device, the screen size, and the like. W _1, for example, preferably 10% of the length of the diagonal of the optical film, more preferably 5% or less, and further preferably 1% or less. In addition, W _{1 is} preferably 50 mm or less, more preferably 10 mm or less, still more preferably 5 mm or less, and even more preferably 1 mm or less. From the viewpoint of preventing the peeling of the optical film 11 and the transparent member on the front surface by using the first adhesive layer 21 with certainty, it is preferable that W _{1 is such} that the constituent members of the image display device can be prevented from being adhered to the first member. The range of physical interference of the agent layer is as small as possible.

The area of the optical film 11 is not particularly limited, but is generally about 5 to 25000 cm ² . When the optical film 11 is rectangular, the length of the diagonal is about 3 to 250 cm. In particular, in a medium-sized or small-sized image display device having an area of 2000 cm ² or less, the effect of space saving obtained by the structure of the present invention is large.

When the optical film 11 is rectangular, it may be a rectangle with long sides and short sides, or a square with the same length of four sides. The length of the long side of the rectangle is generally 10 times or less the length of the short side, and it can be 5 times or less, 3 times or less than 2 times. In the case where the optical film is an optically anisotropic film such as a polarizing plate or a retardation film, the direction of the optical axis such as the absorption axis or the retardation axis may be parallel or perpendicular to the extending direction of the side of the rectangle, or may be parallel to the side of the rectangle. The extension direction is at a specific angle. In the case where the optical film is a laminated body of a plurality of films, the configuration of the optical axis of each film is not particularly limited, and may be parallel or orthogonal, or may be at a specific angle. For example, in the case of a circularly polarizing plate, the polarizing element and the quarter-wave plate are laminated so that an angle formed by the absorption axis direction of the polarizing element and the retardation axis direction of the quarter-wave plate becomes 45 °.

In the double-sided adhesive-attached optical film of the first embodiment, a part of the region along the periphery of the optical film 11 is a non-adhesive region, and in other regions, a first adhesive layer 21 is attached to the periphery of the optical film 11. An end portion of the first main surface is covered by the first adhesive layer 21. The areas where physical interference between the adhesive and the constituent elements of the image display device should be avoided are set as non-adhesive areas, and the other areas are the areas where the adhesive layer 21 is also provided on the periphery of the optical film 11, so that the adhesion can be reliably used The agent layer 21 prevents the peeling by bonding the optical film 11 to a cover glass or the like.

(Protective sheet) FIG. 2 is a cross-sectional view of an optical film 451 with an adhesive on both sides provided with a protective sheet on the adhesive layer. A first protective sheet 41 is detachably attached to the first adhesive layer 21, and a second protective sheet 42 is detachably attached to the second adhesive layer 22. If the protective sheet is temporarily adhered to the adhesive layer in this way, the exposed surfaces of the adhesive layers 21 and 22 can be protected while the optical film 11 is adhered to the adherend.

As a constituent material of the protective sheets 41 and 42, plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester film are preferred. The thickness of the protective sheets 41 and 42 is usually 5 to 200 μm, and preferably about 10 to 150 μm. The protective sheet may be subjected to a peeling treatment with a silicone release agent or the like on the bonding surface with the adhesive.

(Formation of Adhesive Layer and Non-Adhesive Area on Optical Film) As a method of providing the first adhesive layer 21 and the second adhesive layer 22 on the optical film 11, the method of applying the adhesive composition to a peeling process can be cited. A method of applying an adhesive composition to the optical film 11 by forming a pressure-sensitive adhesive layer on a sheet or the like, and then transferring the pressure-sensitive adhesive composition to the optical film 11. If necessary, the adhesive composition after coating may be subjected to solvent removal, crosslinking treatment, hardening treatment, and the like.

As a method of locally disposing the non-adhesive region 2x on the main surface of the optical film 11, a method of controlling the attachment area of the first adhesive layer 21 on the optical film 11 and a method of attaching the entire surface of the main surface of the optical film Method for removing the adhesive layer in a specific area after the first adhesive layer 21. It is also possible to form a non-adhesive region by laminating an adhesive layer with an area smaller than that of the optical film on the optical film adjusted to a size for bonding to the image display device. In addition, a specific region of the adhesive layer provided on the entire surface of the optical film adjusted to a size for bonding to the image display device may be removed to form a non-adhesive region.

You can also use a Thomson knife, a round knife, a dish knife, a laser cutter, etc. to cut the optical film with a double-sided adhesive film that is larger in size than the optical film used for bonding to the image display device. size. An optical film with a double-sided adhesive on the periphery of the optical film having a non-adhesive region 2x can also be produced by arranging a region where the first adhesive layer is not provided on the optical film and cutting off the region. For example, when cutting an elongated double-sided optical film with an adhesive to a specific size, as long as the area where the first adhesive layer is not provided is cut on the optical film, a non-adhesive film can be obtained along the cutting line. Optical film with adhesive on both sides of the area. Multiple films can be cut from a large-size single-piece film (mother substrate), or a film of a specific size can be further cut to produce an optical film with adhesive on both sides with non-adhesive regions on the periphery.

In the non-adhesion area 2x, the protection sheet 41 preferably covers the first main surface of the adhesive layer 21. The position of the end surface 41e of the protective sheet 41 may be aligned with the end surface 21e of the adhesive layer 21, or may be aligned with the end surface 11e of the optical film 11. The end surface 41e of the protective sheet 41 may be located between the end surface 21e of the adhesive layer 21 and the end surface 11e of the optical film 11, or may be located further outside than the end surface 11e of the optical film 11.

If an area where the first adhesive layer is not attached is provided on the optical film, and the entire area of the area where the adhesive layer is attached and the area where no adhesive is attached are cut by the protective sheet to a single sheet size, such as As shown in FIG. 2, the positions of the end surface 11 e of the optical film 11 and the end surface 41 e of the protective sheet 41 are aligned in both the bonding region and the non-bonding region. In the non-adhesion area 2x, as long as the end surface 21e of the adhesive layer 21 exists on the inner side than the end surface 11e of the optical film 11 and the end surface 41e of the protective sheet 41, the paste contamination or paste on the end surface 21e of the adhesive layer can be suppressed. Agent defect.

The adhering area of the periphery of the optical film may be provided with a first adhesive layer attached to the surface of the optical film without exposing the main surface of the optical film. In the adjoining area, the position of the end surface of the protective sheet 41 and the position of the end surface of the first adhesive layer 21 can be aligned, and the end surface of the protection sheet 41 can be positioned more outward than the end surface of the first adhesive layer 21.

Alternatively, as shown in FIG. 3, the optical film 53 with adhesive on both sides is located at the central portion in the thickness direction of the first adhesive layer 21, and the end surface 21 c is located closer to the end surface of the optical film 11 and the first protection sheet 41. Further inside. In the bonding region, the end surface 21c of the central portion in the thickness direction of the adhesive layer 21 exists more inward than the end surface of the optical film 11, which can suppress the transportation or bonding of the optical film with the adhesive on both sides. Contamination or defect of paste on the production line.

For example, by cutting the double-sided optical film with an adhesive under a state of pressure on the side of the autonomous surface, at the interface with the optical film, the position of the end face of the adhesive layer is consistent with the position of the end face of the optical film, and The central portion in the thickness direction of the adhesive layer can cause the end surface of the adhesive layer to be located inside. When the protective films 41 and 42 are attached to the adhesive layers 21 and 22, the optical film with the adhesive on both sides is pressed, the adhesive layer is elastically deformed, and becomes the adhesive at the central portion in the thickness direction. A state where the end of the layer protrudes from the end of the optical film. If the adhesive layers 21 and 22 are cut together with the optical films 11 and the protective sheets 41 and 42 in this state, the positions of the end faces of the optical film 11 and the protective sheets 41 and 42 and the adhesive layers 21 and 22 are cut. The end faces are aligned. If the pressure is released after cutting, due to the deformation of the adhesive, the end face of the central portion in the thickness direction of the adhesive layer recedes to the inner side than the end face of the optical film 11 to obtain the adhesive layer as shown in FIG. An optical film with an adhesive on both sides of which the end face of the central portion in the thickness direction is located on the inside.

When the end face of the central portion in the thickness direction of the first adhesive layer 21 is located more inward than the end face of the optical film 11 in the bonding region, the end surface of the optical film 11 and the central portion in the thickness direction of the first adhesive layer The distance W _{2 of the} end faces is, for example, about 5 μm to 300 μm. From the viewpoint of suppressing both the protrusion of the adhesive from the end surface and the adhesion of the end portion, W _{2 is more} preferably about 10 μm to 100 μm, and more preferably about 15 μm to 70 μm. W ₂ and W ₁ may be the same or different. In general, W ₂ &lt; W ₁ .

The double-sided adhesive-attached optical film 51 shown in FIG. _{1 is} provided with a non-adhesion region 2x along one short side 11 a ₁ of the four sides of the rectangular optical film 11. The non-adhesive area can be set on more than two sides of the rectangle, or on the long side of the rectangle. In the non-adhesive region, the end face of the first adhesive layer need not extend parallel to the edge of the optical film. For example, the non-adhesion region may have a portion whose width decreases from the end of the edge of the rectangle (the vertex of the rectangle) toward the center side of the edge. The non-adhesion area need not be provided along the entire length of the side. For example, a non-adjoining region may be provided only on a part of the edge of the rectangle or the vertex of the rectangle.

The shape of the optical film is not limited to a rectangle, and may be an appropriate shape according to the shape or size of the screen of the image display device. For example, the top view shape of the optical film may be a triangle, a rhombus, a parallelogram, a trapezoid, a pentagon, or a hexagon, such as a polygon, a circle, an oval, or a star.

<Image Display Device> FIG. 4 is a cross-sectional view of an image display device 101 manufactured using an optical film 51 with a double-sided adhesive. In the image display device 101, an optical film 11 is disposed on the image display unit 60, and a cover glass 71 with a touch sensor is provided on the visual side of the optical film 11. The optical film 11 and the image display unit 60 are bonded via the second adhesive layer 22, and the optical film 11 and the cover glass 71 are bonded via the first adhesive layer 21. The image display unit 60 is, for example, a liquid crystal cell, an organic EL (OLED), or a micro LED (Light Emitting Diode). Instead of the cover glass 71, a transparent resin plate containing a transparent resin material such as an acrylic resin may be used.

A flexible printed wiring board (FPC) 91 as an electrical connection member is connected to a touch sensor (not shown) provided on the side facing the optical film 11 near the end of the cover glass 71. The FPC91 is bent so as to wrap around to the back side of the image display unit 60.

FIG. 5 is a cross-sectional view of an image display device 501 using a conventional double-sided optical film 551 with an adhesive. The image display device 501 has a similar structure to the image display device 101 of FIG. 4, but an adhesive layer 521 between the optical film 11 and the cover glass 571 is provided on the entire surface of the optical film.

In the image display device 501, along the entire periphery of the peripheral edge of the optical film 11, the end surface 11e is aligned with the end surface 521e of the adhesive layer 521, and the entire space between the optical film 11 and the cover glass 571 is formed by the adhesive layer 521. cover. Since there is no gap between the optical film 11 and the cover glass 571, a contact point 507a of the touch sensor and the FPC591 is disposed further outside than the end surface 11e of the optical film 11. Since it is necessary to secure a space for accommodating electrical connection members such as FPCs outside the display area of the screen, it is difficult to reduce the width of the frame area around the screen.

On the other hand, in the image display device 101 of FIG. 4 using the double-sided adhesive-attached optical film 51 of the present invention, by arranging the FPC91 in a space along the non-adhesion area 2x along the side 11a ₁ , the A contact 7a between the touch sensor and the FPC 91 is provided on the end surface 11e of the film 11 or further inside than the end surface 11e. In this way, a non-adhesive region 2x without the first adhesive layer 21 is provided on the optical film 11, and FPC and the like are arranged in the gap portion thereof, and the periphery of the screen and the space around it are effectively used, thereby achieving narrow margins. .

As described above, the end surface 21c of the central portion in the thickness direction of the first adhesive layer 21 may be located further inward than the end surface of the optical film 11 in the area following the peripheral edge of the optical film (see FIG. 3). In this form, even when the distance W ₂ between the end surface 21c of the first adhesive layer 21 and the end surface of the optical film in the bonding region is large, the attachment interface of the optical film 11 and the attachment interface of the protective sheet 41 The positions of the end faces of the first adhesive layer and the end faces of the optical film 11 and the protective sheet 41 are also the same. Therefore, even in the case where W _{2 is} large, it is difficult to avoid physical interference between the FPC and the like and the adhesive layer in the bonding region, and narrowing of the edge is required.

The use form of the optical film 51 with a double-sided adhesive having a non-adhesive region on one side is not limited to the configuration shown in FIG. 4, and it can also be applied to an image display device having other configurations. For example, as in the image display device 102 shown in FIG. 6, a decorative printing 72 a may be applied to the cover glass 72 disposed on the surface, and the peripheral edge of the screen facing the optical film 11. In this embodiment, the FPC91 is arranged in a space outside the non-adhesion area 2x which is outside the decorative printing 72a of the cover glass 71, and a contact point 7a of the touch sensor and the FPC is set.

Alternatively, as in the image display device 103 shown in FIG. 7, the optical film 11 and the touch sensor 73 may be bonded via the first adhesive layer 21, and the optical film 11 and the touch sensor 73 may be bonded to each other via the other adhesive layer 29. Laminate cover glass 79.

In the image display device, the first adhesive layer 21 side of the double-sided adhesive-attached optical film does not need to be disposed on the viewing side, and the first adhesive layer 21 may also be disposed on the image display unit side. For example, in the image display device 104 shown in FIG. 8, a polarizing plate 17 having a touch sensor is bonded to the image display unit 60 via the first adhesive layer 21, and the polarizing plate 17 is attached to the polarizing plate 17. A cover glass 79 is bonded on the second adhesive layer 22. An FPC 91 is connected to a touch sensor provided on a surface facing the image display unit 60 near the end of the polarizing plate 17 as an optical film. In this embodiment, the area where the FPC contact 7a is provided between the image display unit 60 and the polarizing plate 17 as an optical film is set as the non-adhesion area 2x, and space can be effectively used.

<Modification of the first embodiment> As described above, the position where the non-adhesive region is set on the first main surface of the optical film is not limited to the short side of the rectangle. For example, as shown in FIG. 9, the double-sided adhesive-attached optical film 56 may have a non-adhesion region 2x of the first main surface on which the optical film 11 is exposed on the two long sides 11a ₂ and 11a _{4 of the} rectangle.

FIG. 10 is a schematic perspective view of an image display device 106 manufactured using the double-sided adhesive-attached optical film 56 of FIG. 9. The image display device 106 is provided with a cover glass 74 on the visible side surface, and an end portion of the cover glass 74 is coupled to the case 84. The long side 74 a of the cover glass 74 extending in the x direction is curved. As long as the curved portion 74a of the cover glass 74 is disposed on the non-adhesion area 2x of the optical film with double-sided adhesive, physical interference between the first adhesive layer 21 and the cover glass 74 can be avoided, and the device can be effectively used Inside the space.

In FIG. 10, the long side 74 a of the cover glass 74 has a shape that is chamfered into a curved shape, but the long side of the cover glass may also have a shape that is chamfered into a flat shape. In addition, the apex portion of the cover glass may be chamfered into a flat shape or a curved shape. The shape of the outer surface and the inner surface of the chamfered shape of the front surface transparent plate such as cover glass or the casing may be the same or different. In addition, the shell can be arranged in the non-adhesion area to avoid physical interference between the adhesive layer and the shell.

11 and 12 are top views of the first main surface side of the optical film with a double-sided adhesive agent in another embodiment, respectively. The double-sided adhesive-attached optical film 57A shown in FIG. 11 has non-adhesive regions 2x ₁ with radians at the four vertices of a rectangle. For example, if the double-sided optical film 57A with an adhesive is used in an image display device with a transparent surface or a shell before the apex of the rectangle has a shape with radians, the curved shape near the apex of the display area can be avoided Part of the physical interference with the first adhesive layer 21 effectively utilizes the space in the device.

The double-sided adhesive film 57B shown in FIG. 12 has non-adhesive regions 2x ₁ with radians at both ends of one short side 11a ₃ and non-adhesive regions 2x along the entire length of the other short side 11a ₁ . ₂ . 12, then the non-provided region of 2x ₂ also along the entire length of the short side 11a ₁ is linear, with no arc angle along the short side 11a _1. In this way, the non-adhesion area provided along the edge can be used to avoid physical interference with the front surface transparent member or the housing, as well as avoid physical interference with constituent members such as FPC.

FIG. 13 is a plan view of the first main surface side of the double-sided adhesive-attached optical film 58 having a non-adhesive region on one side. The double-sided adhesive-attached optical film 58 has a slit-shaped non-adhesive region 2x ₃ on the rectangular short side 11 a ₁ .

FIG. 14 is a cross-sectional view of an image display device 108 made using a double-sided optical film 58 with an adhesive. In the image display device 108, in order to ground the image display unit 60 and the optical film 11, a lead wire 98 is provided. Then the non-area ₃ 2x, the optical film 11 is not on the first adhesive agent layer 21 is provided and the optical film 11 is exposed, and therefore may be in the first main surface of the optical film 11 is provided a wire 98 of the ground contact point 8a. The conductive wire 98 can be formed by a metal wire, a metal paste, or the like. An insulating layer such as a resin coating layer may be provided on the surface of the lead in order to prevent oxidation of the metal constituting the lead 98 or the like.

As an example of the constituent member of the image display device provided on the non-adhesive area on the first main surface of the optical film, an example in which a contact with the FPC is provided in the non-adhesive area, a front surface transparent plate or An example of the casing and an example of the contact with the lead are provided, but the configuration of the image display device is not limited to these, and the components arranged in the non-adhesion area are not particularly limited. The component provided in the non-adhesion area may be any conductive material or insulating material. For example, a conductive material or a resin material may be provided so as to cover the non-adhesion area on the first main surface of the optical film and the side surface of the optical film.

The conductive material or the resin material may be provided so as to further cover the surface of the image display panel. For example, the organic EL unit is sealed by providing a resin layer so as to cover the surface of the organic EL unit and the side surface of the optical film, thereby suppressing deterioration of the organic EL.

The image display unit need not be planar. For example, the entire surface of the image display unit may be curved, or the end of the image display unit may be curved. When the end portion of the image display unit is curved, the non-adhesion region may be included in the curved portion. The conductive material or the resin material may be provided so as to cover the surface of the image display panel. In addition, the image display unit may be curved in a non-display portion such as a connection area with the FPC.

In the double-sided optical film with an adhesive, the second adhesive layer 22 can also be disposed so as to cover the entire surface of the second main surface of the optical film. Since there is no non-adhesion area along the entire periphery of the periphery of the second main surface, the image display unit 60 and the like can be reliably bonded to the optical film 11 to prevent peeling from the end portion. In addition to providing a non-adhesive region on the first main surface of the optical film, a non-adhesive region may also be disposed on the second main surface to avoid physical interference with the constituent members of the image display device.

[Second Embodiment] The double-sided adhesive-attached optical film of the second embodiment has a region along which the optical film is exposed without a first adhesive layer along the entire periphery of the first main surface of the optical film ( Non-adjacent area). In this embodiment, the non-adhesion region may have regions with different widths along the periphery of the first main surface of the optical film. The optical film with adhesive on both sides of the second embodiment has a non-adhesive region along the entire periphery of the first main surface of the optical film 11, and there is no adhesive region on the periphery of the first main surface of the optical film 11. Other than that, the structure of the double-sided adhesive film with an adhesive in the second embodiment is the same as that in the first embodiment.

An example of the double-sided optical film with an adhesive in the second embodiment is shown in FIG. 15. FIG. 15A is a top view of the first main surface side of the double-sided optical film 251 with an adhesive, and FIG. 15B is a cross-sectional view taken along line B1-B2. The optical film with a double-sided adhesive in the second embodiment is provided with a first adhesive layer 21 on one side of the optical film 11 and a second adhesive layer 22 on the other side, as in the first embodiment. A protective sheet (not shown) may be temporarily adhered to the surfaces of the adhesive layers 21 and 22.

The width W ₁₁ of the non-adhesive region 2x ₄₁ along one short side 11 a ₁ of the double-sided adhesive-attached optical film 251 is different from the width W ₁₃ of the non-adhesive region 2 x ₄₃ along the other short side 11 a ₃ . For example, when forming an image display device, the space of the non-adhesive area 2x ₄₁ becomes the area for the FPC to connect to the touch sensor, and the space of the non-adhesive area 2x ₄₃ becomes the cover glass to avoid the curved shape with the end. Or the area of physical interference, such as the shell. The non-adhesive regions along the long sides 11a ₂ and 11a ₄ of the rectangle of the optical film 11 also become areas for avoiding physical interference with the cover glass, the housing, or the like. In this way, the width of the non-adhesive region can be adjusted according to the object that should avoid physical interference, while taking into account the effective use of space and the reliability of adhesion by the first adhesive layer.

The ratio of the maximum value to the minimum value of the width of the non-adhesive region is not particularly limited. The maximum value of the width of the non-adhesive region is, for example, 1.1 times or more the minimum value of the width of the non-adhesive region. The maximum value of the width of the non-adhesive region may be more than 1.3 times the minimum value of the width of the non-adhesive region, may be 1.5 times or more, may be 2 times or more, and may be 3 times or more.

FIG. 16 is a plan view of the first main surface side of the optical film 253 with a double-sided adhesive. The optical film 253 is attached to the adhesive of the double-sided, then the width of the non-2x ₅ regions of approximately uniform in the central portion of the sides of the rectangle. Near the apex of a rectangle, followed by a non-planar shape to become regions with 2x ₅ radian, then the width of the non-edge area from the end side toward the center of the rectangle becomes smaller. If an optical film 253 with a double-sided adhesive with a non-adhesive area 2x ₅ having such a shape is used, the entire periphery of the periphery of the display area can be avoided, and the components of the image display device such as cover glass or housing can be avoided. Physical interference.

[Third Embodiment] The non-adhesive region of the optical film with double-sided adhesive may be provided in a region other than the peripheral edge of the optical film. The optical film with a double-sided adhesive agent in the third embodiment has a region (non-adhesion region) on the inner side of the first main surface of the optical film, where the optical film is exposed without a first adhesive layer. Other than that, the configuration of the double-sided adhesive-attached optical film of the third embodiment is the same as that of the first embodiment and the second embodiment. A protective sheet (not shown) may be temporarily adhered to the surfaces of the adhesive layers 21 and 22 similarly to the first embodiment and the second embodiment of the double-sided optical film with an adhesive in the third embodiment.

An example of the double-sided optical film with an adhesive in the third embodiment is shown in FIG. 17. FIG. 17 is a top view of the first main surface side of the optical film 351 with a double-sided adhesive. FIG. 18 is a yz cross-sectional view (a cross-sectional view taken along the short-side direction of FIG. 17) of an image display device 109 made using an optical film 351 with a double-sided adhesive.

The double-sided adhesive-attached optical film 351 has a non-adhesion region 2x ₆ extending in parallel to the long side on the inner side of the long side 11 a ₄ . In the image display device 109, an optical film 11 is disposed on the image display unit 60, and a cover glass 372 is provided on a viewing side of the optical film 11. The optical film 11 and the image display unit 60 are bonded via the second adhesive layer 22, and the optical film 11 and the cover glass 372 are bonded via the first adhesive layer 21. The cover glass 372 with the decorative print is applied to the surface 11 of the optical film to the optical film of the double-sided adhesive attachment 351 of the non-overlapping then 2x ₆ regions 372a of the raised portion by way of the decorative printing of generated Configuration.

In the image display device 109, an adhesive layer is not provided directly under the raised portion 372a caused by the decoration printing, and there is no accompanying compression deformation of the adhesive caused by the raised portion. Therefore, it is possible to suppress peeling of the adhesive from the raised portion or display unevenness caused by the compressive stress of the adhesive.

The double-sided adhesive-attached optical film of FIG. 17 is equivalent to the first embodiment because it has a non-adhesion region 2x ₆ on the short sides 11a ₁ and 11a ₃ of the rectangle. As shown in FIG. 19, the optical film 352 with double-sided adhesive on the top view is also shown. The optical film with double-sided adhesive on the third embodiment does not have a non-adhesion region on the periphery of the optical film 11, but only on the periphery. then the inner region having a non 2x _7.

The double-sided optical film with an adhesive may have a non-adhesive region in both the region along the periphery of the first main surface of the optical film and the region inside the periphery. For example, as shown in a plan view in FIG. 20, the double-sided adhesive-attached optical film 353 has a non-adhesive region 2x along the short side 11a ₁ of the rectangle and a non-adhesive region 2x ₆ inside the long side 11a ₄ .

The non-adhesive region existing on the peripheral edge of the first main surface and the non-adhesive region existing on the inner side of the peripheral edge may be connected to form a whole or may not be connected. For example, FIG. 21 also shows a plan view of a double-sided optical film attached to the adhesive 355 like, having ends extending along the side of the rectangles 11a ₁ of the non-parallel region followed by 2x _8, and is provided on the sides 11a ₃ The non-adjoining area 2x ₁ near its vertex.

As described above, the double-sided adhesive-attached optical film of the present invention is provided with an adhesive layer on both sides of the optical film, and has an area where the optical film is exposed without an adhesive layer on at least one side. When the non-adhesive region is present, a gap is formed between the optical film and the adherend when the image display device is formed. By arranging the constituent elements of the image display device in the space, physical interference with the adhesive can be avoided, and space can be effectively used, which contributes to space saving and narrow edge of the image display device.

2x‧‧‧ non-adjoining area

2x ₁ ‧‧‧ non-adjoining area

2x ₂ ‧‧‧ non-adjoining area

2x ₃ ‧‧‧ non-adjoining area

2x ₅ ‧‧‧ non-adjoining area

2x ₆ ‧‧‧ non-adjoining area

2x ₇ ‧‧‧ non-adjoining area

2x ₈ ‧‧‧ non-adjoining area

2x ₄₁ ‧‧‧ non-adjoining area

2x ₄₃ ‧‧‧ non-adjoining area

7a‧‧‧Contact

8a‧‧‧ ground

11‧‧‧ Optical Film

11a ₁ ‧‧‧ side

11a ₂ ‧‧‧ side

11a ₃ ‧‧‧‧‧ side

11a ₄ ‧‧‧ side

11e‧‧‧face

17‧‧‧ polarizing plate

21‧‧‧Adhesive layer

21c‧‧‧face

21e‧‧‧face

22‧‧‧ Adhesive layer

29‧‧‧ Adhesive layer

41‧‧‧protective film

41e‧‧‧face

42‧‧‧protective film

51‧‧‧ Optical film with adhesive

53‧‧‧Optical film with adhesive

56‧‧‧ Optical film with adhesive

57A‧‧‧Optical film with adhesive

57B‧‧‧ Optical film with adhesive

58‧‧‧ Optical film with adhesive

60‧‧‧Image display unit

71‧‧‧ Cover glass with touch sensor

72‧‧‧ Cover glass with touch sensor

72a ‧ ‧ bulge (printing department)

73‧‧‧touch sensor

74‧‧‧ Covered glass

74a‧‧‧long side

79‧‧‧ Covered glass

84‧‧‧shell

91‧‧‧flexible printed wiring board

98‧‧‧Wire

101‧‧‧Image display device

102‧‧‧Image display device

103‧‧‧Image display device

104‧‧‧Image display device

106‧‧‧Image display device

108‧‧‧Image display device

109‧‧‧Image display device

251‧‧‧Optical film with adhesive

253‧‧‧ Optical film with adhesive

351‧‧‧Optical film with adhesive

352‧‧‧ Optical film with adhesive

353‧‧‧Optical film with adhesive

355‧‧‧Optical film with adhesive

372‧‧‧ Cover glass with touch sensor

372a ‧ ‧ bulge (printing department)

451‧‧‧Optical film with adhesive

501‧‧‧Image display device

507a‧‧‧contact

521‧‧‧Adhesive layer

521e‧‧‧face

551‧‧‧Optical film with adhesive

571‧‧‧ Covered glass

591‧‧‧flexible printed wiring board

W ₁ ‧‧‧Width

W ₂ ‧‧‧Distance

W ₁₁ ‧‧‧Width

W ₁₃ ‧‧‧Width

FIG. 1A is a top view of an optical film with double-sided adhesive, and B is a cross-sectional view of an optical film with double-sided adhesive. FIG. 2 is a cross-sectional view of an optical film with a double-sided adhesive film provided with a protective sheet on the adhesive sheet. FIG. 3 is a cross-sectional view of an optical film with a double-sided adhesive film provided with a protective sheet on the adhesive sheet. FIG. 4 is a sectional view of the image display device. FIG. 5 is a cross-sectional view of a prior art image display device. FIG. 6 is a sectional view of the image display device. FIG. 7 is a sectional view of the image display device. FIG. 8 is a cross-sectional view of an image display device. FIG. 9 is a top view of an optical film with double-sided adhesive. FIG. 10 is a schematic perspective view of an image display device. FIG. 11 is a top view of an optical film with double-sided adhesive. FIG. 12 is a top view of an optical film with double-sided adhesive. FIG. 13 is a top view of an optical film with a double-sided adhesive. Fig. 14 is a sectional view of an image display device. 15A is a top view of an optical film with double-sided adhesive, and B is a cross-sectional view of an optical film with double-sided adhesive. FIG. 16 is a top view of an optical film with double-sided adhesive. FIG. 17 is a top view of an optical film with double-sided adhesive. FIG. 18 is a sectional view of an image display device. FIG. 19 is a top view of an optical film with a double-sided adhesive. FIG. 20 is a top view of an optical film with a double-sided adhesive. FIG. 21 is a top view of an optical film with double-sided adhesive.

Claims (20)

An optical film with adhesive on both sides includes: an optical film having a first main surface and a second main surface; a first adhesive layer provided on the first main surface of the optical film; and the optical device A second adhesive layer on the second main surface of the film, and along the periphery of the first main surface of the optical film, there is a non-adhesion area where the optical film is exposed without the first adhesive layer, and The bonding region of the first adhesive layer is attached to the optical film. For example, the optical film with adhesive on both sides of claim 1, wherein the optical film is rectangular and has the non-adhesive region along at least one side of the rectangle and the adhesive region along at least one side of the rectangle. For example, the double-sided adhesive-attached optical film of claim 1, wherein in the above-mentioned bonding area, the first adhesive layer is located at the interface with the optical film, the position of the end face of the adhesive layer and the end face of the optical film The positions are the same, and at the central portion in the thickness direction of the first adhesive layer, the end face of the adhesive layer is located more inward than the end face of the optical film. An optical film with adhesive on both sides includes: an optical film having a first main surface and a second main surface; a first adhesive layer provided on the first main surface of the optical film; and the optical device The second adhesive layer on the second main surface of the film has a non-adhesion area along the entire periphery of the first main surface of the optical film, where the first adhesive layer is not provided and the optical film is exposed, and Along the periphery of the first main surface of the optical film, there are regions with different widths of the non-adhesion regions. For example, the optical film with an adhesive on both sides of claim 4, wherein the optical film is rectangular, and the width of the non-adhesive region on one side of the rectangle is different from the width of the non-adhesive region on the other side of the rectangle. The double-sided adhesive-attached optical film according to any one of claims 1 to 5, wherein in the non-adhesive region, an end face of the optical film and an end face of the first adhesive layer are parallel to a peripheral edge of the optical film Ground extension. The double-sided adhesive-attached optical film according to any one of claims 1 to 5, wherein the optical film is rectangular, and the non-adhesion region has a portion whose width decreases from an end of a side of the rectangle toward the center side. An optical film with adhesive on both sides includes: an optical film having a first main surface and a second main surface; a first adhesive layer provided on the first main surface of the optical film; and the optical device The second adhesive layer on the second main surface of the film has a non-adhesive region on the inner side of the first main surface of the optical film, where the first adhesive layer is not provided and the optical film is exposed. The optical film with a double-sided adhesive as described in any one of claims 1 to 5 and 8 has the above-mentioned non-adhesive region having a width of 10 μm or more. For example, the optical film with a double-sided adhesive agent according to any one of claims 1 to 5 and 8, wherein the second adhesive layer is provided along the entire circumference of the periphery of the second main surface of the optical film, instead of There is a region where the second main surface of the optical film is exposed. The double-sided adhesive film according to any one of claims 1 to 5 and 8, wherein the optical film includes a polarizing plate. For example, the optical film with double-sided adhesives according to any one of claims 1 to 5 and 8, wherein a first protective sheet is releasably attached to the first adhesive layer and the second adhesive layer is provided. A second protective sheet is releasably attached thereto. For example, the adhesive-coated optical film with double-sided adhesive of claim 12, wherein the position of the end surface of the optical film and the end surface of the first protective sheet are aligned along the entire circumference of the peripheral edge of the optical film. An image display device comprising an image display unit, a double-sided optical film with an adhesive as described in any one of claims 1 to 13, and a front surface transparent member, the optical film and the image display unit The optical film and the front surface transparent member are bonded via one of the first adhesive layer and the second adhesive layer, and the other of the first adhesive layer and the second adhesive layer is bonded. And the constituent members of the image display device are arranged on the non-adhesion area on the first main surface of the optical film. The image display device according to claim 14, wherein the front surface transparent member is a touch sensor or a transparent plate. According to the image display device of claim 14, wherein the front surface transparent member is a touch sensor, the optical film and the touch sensor are bonded via the first adhesive layer, and are in the non-adhesion area. The touch sensor is connected to the electrical connection member. The image display device according to claim 14, wherein the optical film is provided with a touch sensor, and in the non-adhesion area, the optical film is connected to an electrical connection member. The image display device according to claim 14, wherein the front surface transparent member is disposed in the non-adhesion area. The image display device according to claim 14, wherein a casing is disposed in the non-adhesion area. The image display device according to claim 14, wherein a conductive material or a resin material is provided in contact with the first main surface of the optical film in the non-adhesion area.