JP5458691B2 - Electro-optical device and electronic apparatus - Google Patents

Description

  The present invention relates to an electro-optical device and an electronic apparatus including the electro-optical device.

A thin panel and a flat panel display used for a mobile phone are required to be thin and lightweight. Recently, a flat panel display with flexibility has been proposed for developing new applications.
For example, Patent Document 1 proposes an organic EL display device in which an organic EL (Electro Luminescence) layer is sandwiched between two glass substrates thinned to 100 μm or less. In addition, this document also describes that a resinous reinforcing layer is provided on the outside of the front and back glass substrates in order to compensate for the lack of strength associated with the reduction in thickness.

Also, in Patent Document 2, as shown in FIG. 13, a display device 300 having a structure in which a liquid crystal panel 90 made of a pair of thin glass substrates is wrapped and laminated with two transparent resin films 95a and 95b from the front and back surfaces. Has been proposed. Further, a polarizing plate 91 that also serves as a reinforcing layer is disposed on the front surface of the liquid crystal panel 90, and a resinous reinforcing plate 92 is disposed on the back surface. That is, the liquid crystal panel 90 was laminated by the two resin films 95a and 95b in a state where the resin reinforcing plates were attached to the front and back surfaces.
These reinforcing plates and the reinforcing structure by laminating resin films are considered to supplement the characteristics of the glass substrate, which is relatively strong against compressive stress but very weak against tensile stress. Further, this document also describes that the reinforcing structure can be applied to an organic EL panel.

  Here, when the reinforcing structure is applied to an organic EL panel (display panel) that is a self-luminous device, it is necessary to dissipate heat generated during display in order to prevent deterioration of the display panel. Although no consideration is given to heat dissipation in the reinforcing structure, for example, the reinforcing plate 92 on the back side of the display device 300 may be made of aluminum having excellent thermal conductivity.

JP 2005-19082 A Japanese Patent No. 4131639

However, the configuration in which the reinforcing plate 92 on the back side of the display device is made of aluminum has a problem that it is difficult to obtain sufficient heat dissipation. Specifically, because the aluminum reinforcing plate 92 is covered with the resin film 95b, heat is trapped in the laminate structure.
In addition, the configuration in which the reinforcing plate 92 is made of aluminum has a problem that the display device is warped. Specifically, the linear expansion coefficient of a glass substrate used for a display panel is about 4 ppm / ° C., whereas the linear expansion coefficient of aluminum is about 24 ppm / ° C., which is about 5 times. Thin display panel warps. In addition, although the linear expansion coefficient of the resin film or the resin reinforcing plate is larger than that of the glass substrate, the warping stress was offset by making them symmetrical on the front and back surfaces.

Moreover, in the conventional reinforcement structure by the resin-type reinforcement board and the lamination of a resin film, there existed a subject that it was difficult to obtain sufficient practical strength (toughness). This is because the resinous reinforcing plate or resin film attached to the glass substrate bends following the glass substrate when bending stress is applied. In other words, the reinforcing plate and the resin film are easily bent to the limit point (limit radius) of the glass substrate together with the glass substrate, so that the glass substrate may be cracked and cracked. The same was true when the back side reinforcing plate was made of aluminum.
Furthermore, the conventional reinforcing structure has a problem that it is difficult to obtain a sufficient barrier property against moisture intrusion. In the conventional reinforcing structure, the display panel in which the reinforcing plates are attached to the front and back surfaces is laminated by the two resin films 95a and 95b, so that the display panel becomes thick and is laminated. This is because a gap G is generated at the peripheral edge of the display panel (organic EL panel). When the gap G is formed, moisture may enter the gap G, which causes deterioration of the organic EL layer due to moisture.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following application examples or forms.

(Application example)
A resin film that is laminated so as to cover a display panel in which an electro-optic layer is sandwiched between a pair of glass substrates, a first surface on the display area side of the display panel, and a second surface facing the first surface And a reinforcing member is provided on the resin film covering at least the second surface, and the reinforcing member includes a first carbon including a plurality of carbon fibers extending in the first direction in plan view. An electro-optical device comprising a laminated structure of a fiber layer and a second carbon fiber layer including a plurality of carbon fibers extending in a second direction intersecting the first direction.

According to this electro-optical device, the reinforcing member is provided on the back surface thereof. In addition, the reinforcing member is configured to include a laminated structure including a first carbon fiber layer and a second carbon fiber layer.
Here, carbon fiber is carbon fiber made from PAN (polyacrylonitrile), pitch, etc. as a raw material, carbonized with high purity at a high temperature of 1000 ° C. or higher, high tensile strength, low thermal deformation rate (low linear expansion). Coefficient) and high thermal conductivity.
That is, since the reinforcing member containing carbon fiber having higher thermal conductivity than the resin is provided on the outer surface (outermost surface) of the resin film, the conventional display device in which the aluminum reinforcing plate is arranged in the laminate structure The heat generated by the display panel can be radiated to the outside more efficiently.
Furthermore, since the linear expansion coefficient of the reinforcing member having a laminated structure including two carbon fiber layers laminated in the intersecting direction is about 1 ppm / ° C., unlike conventional aluminum in which thermal expansion and contraction was intense, electro-optics Even if it is attached to the back surface of the apparatus, it is possible to prevent warping.
Accordingly, it is possible to provide an electro-optical device that has sufficient heat dissipation and prevents warping.

In addition, since the tensile strength of the carbon fiber is higher than that of a conventional resin reinforcing plate or aluminum, even if a bending stress is applied in the extending direction of the carbon fiber with the reinforcing member attached, It is possible to suppress the glass substrate from bending to the limit point (limit radius).
The reinforcing member further includes a first carbon fiber layer including a plurality of carbon fibers extending in the first direction, and a second carbon including a plurality of carbon fibers extending in the second direction intersecting the first direction. Since it includes a laminated structure with a fiber layer, the tensile strength from all directions increases in both directions, and the glass substrate bends to the limit point (limit radius) regardless of the bending stress applied from any direction. Can be suppressed.
Therefore, according to the electro-optical device according to the application example, sufficient practical strength can be obtained.

  Furthermore, since the reinforcing member is provided on the outer surface of the laminate structure, the display panel can be made thinner than the conventional display device in which the reinforcing plate is attached to the front and back surfaces of the display panel. Therefore, it is possible to reduce a gap generated at the peripheral edge of the display panel when laminating, and to obtain a sufficient barrier property against moisture intrusion.

Further, the reinforcing member preferably includes a graphite layer.
Moreover, it is preferable that the graphite layer is arrange | positioned between the resin film which covers a 2nd surface, and a 1st carbon fiber layer.
Moreover, it is preferable that the graphite layer is arrange | positioned between the 1st carbon fiber layer and the 2nd carbon fiber layer.
The graphite layer preferably has a plurality of holes formed in a plane.
Further, the first carbon fiber layer and the second carbon fiber layer are formed of a prepreg obtained by impregnating carbon fiber with a resin, and the reinforcing member includes three or more layers of the first carbon fiber layer and the second carbon fiber layer. A laminated and cured laminate is preferred.

Further, when the reinforcing member is the first reinforcing member, the second reinforcing member is further provided on the resin film covering the first surface, and the second reinforcing member is opened in the display panel. It is preferable that it is formed so as to have a portion.
The opening shape of the second reinforcing member is preferably provided in the same shape as the display area, and the second reinforcing member is preferably large enough to cover the end of the display panel in plan view.
Moreover, it is preferable that the 2nd reinforcement member is comprised from the laminated structure or invar of a 1st carbon fiber layer and a 2nd carbon fiber layer.
Moreover, it is preferable that the thickness of a glass substrate is 100 micrometers or less, respectively.

The resin film is preferably a polyethylene copolymer material.
Moreover, the optical film which covers a display area is provided in the opening part of the 2nd reinforcement member, and a resin film functions as an adhesive agent which bonds a display panel, a 2nd reinforcement member, and an optical film. Is preferred.

In addition, the display panel is formed with an overhang region in which one side of one of the glass substrates extends beyond the other glass substrate, and one end of the flexible printed circuit board is formed in the overhang region. It is preferable that one end of the flexible printed circuit board is connected with the resin film and the other end of the flexible printed circuit board is exposed to the outside from the end of the resin film.
The electro-optical layer is preferably an organic EL layer including an organic light emitting layer.

  An electronic apparatus comprising the electro-optical device described above as a display unit.

FIG. 6 is a perspective view illustrating one embodiment of a display device according to Embodiment 1; The side sectional view of the display in the ff section of Drawing 1. The enlarged view of the d section in FIG. The schematic diagram which shows the laminated structure of CFRP. The flowchart figure which shows the flow of the manufacturing method of a display apparatus. The figure which shows the manufacture aspect in each process of (a), (b). (A) Sectional drawing of the display apparatus which concerns on Embodiment 2, (b), (c) The perspective view which shows the one aspect | mode of the reinforcing member. Sectional drawing of the display apparatus which concerns on Embodiment 3. FIG. (A) Sectional drawing of the display apparatus which concerns on Embodiment 4, (b) The perspective view which shows the one aspect | mode of a reinforcing member. (A) Sectional drawing of the display apparatus which concerns on Embodiment 5, (b) The perspective view which shows the one aspect | mode of a reinforcing member. (A), (b) The perspective view which shows the electronic book as an electronic device. Sectional drawing of the display panel which concerns on the modification 3. FIG. The sectional side view of the conventional display apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the scale of each layer and each part is different from the actual scale so that each layer and each part can be recognized on the drawing.

(Embodiment 1)
"Overview of display device"
FIG. 1 is a perspective view showing an aspect of the display device according to the present embodiment. FIG. 2 is a side sectional view of the display device taken along the line ff of FIG.
First, an overview of the display device 100 as an electro-optical device according to the first embodiment of the invention will be described.

The display device 100 is a flexible organic EL display device having a structure in which a display panel 18 which is a thin organic EL panel is laminated with two resin films 25a and 25b. In the following description, the laminate structure or the laminated display panel 18 is also referred to as a laminate structure 25.
The display panel 18 includes a display region V composed of a plurality of pixels arranged in a matrix. Further, in order to ensure flexibility, the thickness of the pair of substrates constituting the display panel 18 is set to 100 μm or less. In the display area V, red (R), green (G), and blue (B) color pixels are periodically arranged, and a full color image is displayed by display light emitted from each pixel. Note that the display panel is not limited to a display panel that performs color display, and may be a display panel that performs monochrome display. The display area V has a horizontally long rectangle. In each of the drawings including FIG. 1, the horizontal direction is defined as the X-axis direction, and the vertical direction shorter than the horizontal direction is defined as the Y-axis direction. The thickness direction of the display panel 18 is the Z-axis direction. The surface on the display area V side is referred to as a front surface as the first surface, and the opposite surface is referred to as a back surface as the second surface.

Here, a reinforcing member 30 as a first reinforcing member is attached to the entire back surface of the laminate structure 25. Further, the size of the planar reinforcing member 30 is formed to be approximately the same size as the laminate structure 25. The reinforcing member 30 reinforces the thin display panel 18 and is a member for radiating heat generated by the display panel 18 at the time of display, and has both excellent thermal conductivity and tensile strength, and a glass substrate. It is comprised from the material containing the carbon fiber which has a linear expansion coefficient approximate to. Note that the reinforcing member 30 may be read as the heat radiating member 30. With such a configuration, the display device 100 can achieve both heat dissipation capable of preventing deterioration of the display panel 18 due to heat generation and sufficient practical strength, and can also prevent warpage. In addition, practical strength is having the flexibility which can be bent, and the toughness which the display panel 18 does not break even if it bends, as shown with the dotted line in FIG.
As shown in FIG. 2, the display panel 18 includes an element substrate 1 and a CF (color filter) substrate 16, and one end of the element substrate 1 extends from the CF substrate 16 at one end thereof. An overhang region is formed. A flexible substrate 20 is connected to the overhang region. The flexible substrate is an abbreviation for a flexible printed circuit. In addition, a driving IC (Integrated Circuit) 21 is mounted on the flexible substrate 20, and a plurality of terminals for connecting to an external device are formed at the end thereof.

"Detailed configuration of the display panel"
FIG. 3 is an enlarged view of a portion d in the display panel 18 of FIG.
Next, a detailed configuration of the display panel 18 will be described.
The display panel 18 includes an element substrate 1, an element layer 2, a planarizing layer 4, a pixel electrode 6, a partition wall 7, an organic EL layer 8 as an electro-optic layer, a common electrode 9, an electrode protective layer 10, a buffer layer 11, and a gas barrier layer. 12, a filler 13, a CF layer 14, a CF substrate 16, and the like. A portion sandwiched between the element substrate 1 and the CF substrate 16 is referred to as a functional layer 17. In other words, the laminated structure from the element layer 2 to the CF layer 14 is referred to as a functional layer 17.
The element substrate 1 is made of transparent inorganic glass. In this embodiment, alkali-free glass is used as a suitable example.
In the element layer 2, a pixel circuit for actively driving each pixel is formed. The pixel circuit includes a selection transistor for selecting a pixel made of a TFT (Thin Film Transistor), a driving transistor 3 for flowing a current to the organic EL layer 8, and the like, which are formed corresponding to each pixel. Has been.

In the upper layer (Z-axis (−) direction) of the element layer 2, for example, a planarization layer 4 that is an insulating layer made of an acrylic resin or the like is formed.
The reflective layer 5 and the pixel electrode 6 are laminated in this order on the flattening layer 4 so as to be divided for each pixel. The reflection layer 5 is a reflection layer made of, for example, aluminum, and reflects light traveling from the organic EL layer 8 toward the element substrate 1 to make light that contributes to display.
The pixel electrode 6 is composed of a transparent electrode such as ITO (Indium Tin Oxide) or ZnO, and is connected to a drain terminal of the driving transistor 3 of the element layer 2 and a contact hole penetrating the planarization layer 4 for each pixel. ing.
The partition wall 7 is made of a photocurable black resin or the like, and partitions each pixel in a lattice shape in a plane. Note that the pixel circuit including the driving transistor 3 in the element layer 2 is disposed so as to overlap the partition in a planar manner in order to prevent malfunction due to light.

The organic EL layer 8 is formed so as to cover the pixel electrode 6 and the partition wall 7. In FIG. 3, the structure is a single layer. Actually, each layer is composed of a hole transport layer, a light emitting layer, an electron injection layer, and the like made of an organic thin film. Are stacked. The hole transport layer is made of a sublimable material such as aromatic diamine (TPAB2Me-TPD, α-NPD). The light emitting layer is composed of an organic light emitting material thin film composed of a multilayer that emits white light formed by combining three colors of red, green, and blue. The electron injection layer is made of LiF (lithium fluoride) or the like.
The common electrode 9 is a metal thin film layer in which a metal such as MgAg is formed very thin so as to transmit light. Further, a transparent conductive film such as a metal oxide such as ZnO or a metal nitride layer such as TiN may be stacked in order to lower the resistance.

Electrode protective layer 10, SiO ₂ or, Si ₃ N _4, SiOxNy transparent such, and is configured of a material having a function of blocking water by density.
The buffer layer 11 is a transparent organic buffer layer such as a thermosetting epoxy resin.
The gas barrier layer 12 is a transparent sealing layer such as SiO ₂ , Si ₃ N ₄ , or SiOxNy, and has a function of blocking moisture due to high density, and prevents moisture from entering the organic EL layer 8. Take on the function.
The filler 13 is a transparent adhesive layer made of, for example, a thermosetting epoxy resin, and fills the uneven surface between the gas barrier layer 12 and the CF layer 14 and bonds them together. Further, it also functions to prevent moisture from entering the organic EL layer 8 from the outside.

The CF substrate 16 is made of the same inorganic glass as the element substrate 1, and the CF layer 14 is formed on the organic EL layer 8 side (Z axis (+) side).
In the CF layer 14, a red color filter 14r, a green color filter 14g, and a blue color filter 14b are arranged similarly to the pixel arrangement. Specifically, the color filters of each color are arranged so as to overlap with the corresponding pixel electrodes 6, and light shielding portions indicated by hatching are formed between the color filters. The light shielding portion is formed in a lattice shape so as to overlap the partition wall 7 in a plan view, and optically functions as a black matrix.
The CF substrate 16 and the element substrate 1 are bonded and sealed with a sealing agent 15 formed on the peripheral edge of the CF substrate 16. As the sealant 15, an epoxy adhesive, an ultraviolet curable resin, or the like is used.

From each pixel configured in this manner, display light corresponding to the color tone of the color filter is emitted. For example, in the case of a red pixel, white light emitted from the organic EL layer 8 is selected by the red color filter 14r and emitted from the CF substrate 16 as red display light. The same applies to green and blue pixels.
Thereby, in the display area V, a full-color image is displayed by display light from the plurality of color pixels emitted from the CF substrate 16.
Further, if the reflective layer 5 is eliminated, display can be performed also on the back surface of the display region V. In other words, display can be performed on both the front and back surfaces of the display panel 18.
The configuration of the display panel 18 is not limited to the top emission type, and may be a configuration in which an electro-optical layer is sandwiched between two glass substrates. For example, a bottom emission type organic EL display device that emits light emitted from the organic EL layer 8 from the element substrate 1 side may be used. Moreover, the inorganic EL display device provided with inorganic EL as a light source may be sufficient.

In addition, a flexible substrate 20 is connected to an overhang region in which one side of the element substrate 1 projects from the CF substrate 16. The flexible substrate 20 is, for example, a flexible substrate in which a copper foil wiring, a driver IC, or the like is mounted on a polyimide film base material, and is anisotropic between the transparent electrode formed on the element substrate 1. Electrical connection is made by a conductive adhesive film or the like.
Here, since the mechanical strength is insufficient only by the connection with the anisotropic conductive adhesive film, conventionally, the connection portion of the flexible substrate 20 is covered and molded with silicon resin (adhesive) or the like to be reinforced. However, there was a problem of easy peeling.
In this embodiment, sufficient practical strength and flexibility are ensured by making the resin film 25a function as an adhesive (filler) instead of this reinforcing structure. The resin film adhesion method (lamination method) will be described later.

"Material of laminate structure and reinforcing member"
Returning to FIG.
Subsequently, the materials of the resin films 25a and 25b and the reinforcing member 30 constituting the laminate structure 25 will be described.
The resin films 25a and 25b to be laminated so as to cover the entire surface of the display panel 18 including the display region V to the peripheral edge of the display panel 18 from the front and back surfaces are bonded to the glass substrate and the reinforcing member 30 and are flexible. Functions such as water resistance, transparency (light extraction properties), moldability (insulation and heat resistance) of the flexible substrate 20, and water resistance to prevent moisture from entering the inside are required.
In order to satisfy these functions, the resin films 25a and 25b are preferably made of a resin based on polyethylene having water resistance (low water absorption), insulation, flexibility, transparency, and low-temperature weldability. Moreover, it is more preferable that it is a copolymer partially having a polar group in order to improve adhesiveness.

  Specifically, ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-hydroxyalkyl methacrylate copolymer, ethylene-alkoxy methacrylate alkoxy are used as polyethylene copolymers. Ethyl copolymer, ethylene-aminoethyl methacrylate copolymer, ethylene-hydroxyglycidyl methacrylate copolymer, ethylene-vinyl alcohol copolymer (EVOH), ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid It is preferable to use either an acid copolymer (EMAA) or an ethylene-alkyl acrylate copolymer. Alternatively, a copolymer obtained by combining two or more of these (for example, an ethylene-vinyl acetate-vinyl alcohol copolymer is a copolymer excellent in adhesion between both glass and CFRP), or a mixture is used. There may be.

  Moreover, in order to improve heat resistance, you may contain hardening components, such as amine compounds, such as an epoxy compound, an isocyanate compound, and a polyethyleneimine, as a crosslinking agent. In addition, when using the material which has the carboxyl group which is not esterified among ethylene copolymers, such as ethylene-acrylic acid copolymer (EAA) and ethylene-methacrylic acid copolymer (EMAA), low-temperature weldability However, it is preferable to crosslink with heat in combination with a crosslinking component such as an epoxy-based curing agent so that acrylic acid does not remain.

The reinforcing member 30 includes a glass substrate end portion that is prone to cracking, heat dissipation for dissipating heat generated by the display panel 18, prevention of panel warpage due to a multilayer structure made of materials having different linear expansion coefficients, and a glass substrate. A function such as toughness (tensile resistance) is required to suppress the bending to the limit point (limit radius).
In order to satisfy these functions, a material having a high Young's modulus (10 GPa or more), a high thermal conductivity (10 W / m · k or more), and a low linear expansion coefficient (10 ppm / ° C. or less) is preferable.
In this embodiment, as a suitable example, CFRP (Carbon Fiber Reinforced Plastics) having both excellent tensile strength and heat dissipation is used as the material of the reinforcing member 30. Since CFRP has a low density (1.5 to 2.0 g / cm ³ ) and a high tensile strength (1000 MPa or more), high strength reinforcement is possible even if it is thinned. It is suitable as a material.
The heat conduction of carbon fiber, which is the main component of CFRP, is 20 to 60 W / m · k, which is higher than glass (1 W / m · k) and engineering plastic resin (about 0.5 w / m · k). The reinforcing member 30 has a sufficient function as a heat sink.

FIG. 4 is a schematic view showing a laminated structure of CFRP.
CFRP is a composite material composed of carbon fiber and resin, and is a precursor called prepreg in which carbon fiber aligned in one direction is impregnated with thermosetting resin such as epoxy resin or phenol resin, or thermoplastic such as polyester. It is a composite material in which two or more layers (carbon fiber layers) are laminated in different directions and cured.
Specifically, as shown in FIG. 4, a precursor including a plurality of carbon fibers extending in the X-axis direction is a carbon fiber layer h (first carbon fiber layer), and a plurality of precursors extending in the Y-axis direction. When the carbon fiber layer i (second carbon fiber layer) is used as the precursor containing the carbon fiber, four layers of the carbon fiber layer h and the carbon fiber layer i are alternately stacked, and then pressurization and heating (for example, The reinforcing member 30 is made of CFRP which has been hardened into a plate shape at 120 to 180 ° C.). In addition, in FIG. 4, the line segment shown by stripe form has shown the extending direction of carbon fiber. Further, although the layers are drawn apart for the sake of clarity, they are actually a laminated body that is bonded (contacted) and integrated.
Further, as the carbon fiber, it is preferable to use a PAN (polyacrylonitrile) -based carbon fiber or a pitch (petroleum resin) -based carbon fiber.

In the present embodiment, CFRP having a four-layer structure is adopted as a suitable example, but it is only necessary to include a laminated structure in which two or more carbon fiber layers having different carbon fiber extending directions are laminated. In other words, what is necessary is just to include the laminated structure which consists of two carbon fiber layers piled up so that the extending direction of each carbon fiber may cross | intersect.
Further, when the X-axis direction is about 0 degrees, the basic structure is a front and back symmetrical stacking order in which the extending direction of the carbon fibers is about 0 degrees, about 90 degrees, about 90 degrees, and about 0 degrees. However, the present invention is not limited to this. For example, the stacking order of about 0 degrees, about 90 degrees, about 0 degrees, about 90 degrees, and the stacking of about 0 degrees, about 0 degrees, about 90 degrees, about 90 degrees It may be in order.
Also, in the case of 3 layers, the stacking order is 0 degree, 90 degrees, 0 degrees, and in the case of 6 layers, it is a front / back symmetrical structure such as 0 degrees, 90 degrees, 0 degrees, 0 degrees, 90 degrees, 0 degrees. The order of lamination is fundamental, but these are not limited as described above.
Even if it is these structures, the expected function as the reinforcement member 30 is securable. Specifically, with respect to the tensile strength, 1000 MPa or more can be secured in substantially all planar directions.
Regarding heat dissipation, carbon fiber made of high-purity carbon is high-purity carbon, so heat conduction is 20 to 60 W / m · k, glass (1 W / m · k) and general-purpose plastic (about 0.5 w / k). Since it is higher than m · k), sufficient heat dissipation can be obtained. Furthermore, the outermost surface of the CFRP may be processed so as to increase the surface area by providing an uneven shape on the surface in order to further increase the heat radiation to the atmosphere.

“About the thickness of each part”
Returning to FIG.
Here, the optimal thickness of each part necessary for the display device 100 to achieve both flexibility and practical strength (toughness) will be described.
First, the thickness of the display panel 18 will be described. The display panel 18 is filled with an all-solid material having no hollow structure between the substrates in order to obtain an adhesive strength that can withstand flexibility.
In FIG. 3, in order to clarify the stacking relationship between the constituent parts, in particular, the scale of the functional layer 17 is enlarged as compared with other parts, but in reality, the functional layer 17 is configured to be the thinnest part. become. The thickness of the functional layer 17 is about several μm to 20 μm. Among these, the buffer layer 11 occupies more than half the thickness. Incidentally, the thickness of the organic EL layer 8 composed of a plurality of thin films with a thickness of the order of nm is less than 1 μm.

In this embodiment, as a suitable example, the thickness of the element substrate 1 and the CF substrate 16 is about 40 μm. The total thickness of the display panel 18 is about 90 μm as a preferred example. According to the experiment results of the inventors, in order to ensure the reliability of the organic EL panel, in addition to the sealing structure such as the gas barrier layer 12, the element substrate 1 and the CF substrate 16 must have a thickness of about 10 μm or more. It is understood that. In other words, by setting the thicknesses of the element substrate 1 and the CF substrate 16 to about 10 μm or more, it is possible to ensure impact strength sufficient to withstand flexibility and sufficient moisture resistance.
On the other hand, when the thickness of the element substrate 1 and the CF substrate 16 is about 100 μm or more, it is understood that the flexibility is impaired.
For this reason, it is preferable to set the thickness of the element substrate 1 and the CF substrate 16 within a range of 10 to 100 μm. In consideration of the balance between strength and flexibility, it is more preferable that the thickness be in the range of 20 to 80 μm.
Further, the total thickness of the display panel 18 in which the element substrate 1 and the CF substrate 16 are overlapped is preferably set in a range of 50 to 120 μm in consideration of a balance between strength and flexibility.

  Note that the element substrate 1 and the CF substrate 16 are thinned by polishing or etching each having a thickness of about 0.3 to 0.7 mm in the initial stage. Preferably, after manufacturing a display panel in which the front and back glass substrates are thick, the display panel 18 having a desired thickness is obtained by etching using an etching solution (aqueous solution) in which hydrofluoric acid (hydrofluoric acid) is dissolved. Manufacturing. Note that the present invention is not limited to this method, and any method that can form the display panel 18 having a desired thickness may be used. For example, a mechanical polishing method may be used.

Returning to FIG.
Next, the thickness of the resin films 25a and 25b constituting the laminate structure 25 will be described.
In the present embodiment, as a suitable example, an EVA film having a thickness of about 50 μm is used for the resin films 25a and 25b. According to the experiment results of the inventors, it has been found that a thickness of about 20 μm or more is required to satisfy the coverage (fillability) of the step including the gap at the peripheral edge of the display panel 18.
Considering the balance between the coverage and the total thickness of the display device 100, it is preferably in the range of 20 to 100 μm. Moreover, when the cost of a resin film and the ease (workability | operativity) of lamination are considered, it is preferable to exist in the range of 40-80 micrometers.

Next, the thickness of the reinforcing member 30 will be described.
In this embodiment, CFRP having a four-layer structure and a thickness of about 100 μm is used for the reinforcing member 30 as a preferred example.
The CFRP can be formed as long as it has a thickness of about 25 μm or more. However, the CFRP is flexible and practical in a state of being attached to the laminate structure 25 (including the display panel 18) set to the above-described thickness. In order to ensure strength (toughness), it is necessary to set the thickness within a range of 50 to 200 μm.
The total thickness of the display device 100 formed by laminating these members is about 260 μm at the thickest portion. The peripheral portion of the display panel 18 where the display panel 18 and the reinforcing member 30 overlap is the thickest portion.
Note that the dimensions of the above preferred examples are one of preferred examples derived by the inventors from the experimental results and physical property data after creative ingenuity, and are not limited thereto. Within the range, dimensions can be set according to the application.

"Manufacturing method of display device"
FIG. 5 is a flowchart showing a flow of a manufacturing method of the display device. 6 (a) and 6 (b) are diagrams showing manufacturing modes in each step.
Here, the manufacturing method of the display device 100 will be described in detail along the flowchart of FIG.

In step S1, as shown to Fig.6 (a), it is set as the state which piled up each member (preparation body), and the laminating apparatus. Specifically, the resin film 25b, the display panel 18, and the resin film 25a are superposed on the reinforcing member 30 in this order. Although not shown in FIG. 6 (a), each member is overlapped using a dedicated guide plate, and planar alignment is also performed. Although this step is performed under a normal environment as a suitable example, it may be performed under a reduced pressure environment described later.
Then, the preparation is set in the laminating apparatus. In FIG. 6A, only the pressure rollers 81 and 82 of the laminating apparatus are shown.

In step S2, the environment in which the laminating apparatus and the preparation body are installed is depressurized to form a depressurized environment. The laminating apparatus is installed in a chamber apparatus (room) that can set the internal environment to a desired atmospheric pressure environment. By this step, air (bubbles) inside the preparation body is removed (defoamed).
Further, in parallel, the pressure rollers 81 and 82 are heated, and the roller surface made of a heat-transferable elastomer is heated to a temperature of 80 to 120 ° C.
In step S3, as shown by the arrow in FIG. 6A, the preparation body is inserted between the pair of pressure rollers 81 and 82 from one side of the preparation body on the opposite side of the flexible substrate 20, and lamination is performed. Is called. In the portion sandwiched between the pressure rollers 81 and 82, the resin films 25a and 25b are dissolved by the heat of the rollers, and are further pressurized and bonded to each other. Further, the dissolved resin film functions as an adhesive (filler), and the display panel 18, the flexible substrate 20, and the reinforcing member 30 are also bonded.
In addition, since the lamination is performed from one side to the other end of the preparation body, even if bubbles (air) remain in each member, the bubbles are pushed out to the other end side in the order of lamination. Then, as shown in FIG. 6B, the laminated display device 100 is pushed out between the pressure rollers 81 and 82 to complete the lamination.

In step S4, an annealing process is performed to remove residual stress in the laminated display device 100. The annealing process may be performed continuously in a reduced pressure environment or in a normal environment. In particular, when the resin films 25a and 25b contain a cross-linking component, it is preferable to perform an annealing treatment at about 100 ° C. to complete the cross-linking.
Note that the laminating apparatus is not limited to a roll laminating system including a pair of pressure rollers 81 and 82, and may be any apparatus that can laminate the prepared body to the completed state of the display device 100. For example, vacuum laminating by a diaphragm method (diaphragm method) in which a preparation body is set on one plate-shaped heating plate (hot plate), a deformed rubber sheet is pressed against the preparation body by a pressure difference, and heated and pressurized. An apparatus may be used.

Returning to FIG.
In this way, the display device 100 having both the practical strength (toughness) and the sufficient heat dissipation property as shown in FIG. 2 (FIG. 1) while having flexibility is formed.
The size of the planar reinforcing member 30 is not limited to the same size as the laminate structure 25. For example, from the viewpoint of heat dissipation, it is only necessary to ensure a size that covers the display region V that generates the largest amount of heat. Further, from the viewpoint of strength, it is only necessary to secure a size that covers the peripheral edge of the display panel 18 where cracks are likely to occur during bending.
In other words, the size of the planar reinforcing member 30 may be determined within the range from the size covering the display area V to substantially the same size as the laminate structure 25 according to the required specifications required for the display device 100.

As described above, according to the display device 100 and the manufacturing method according to the present embodiment, the following effects can be obtained.
According to the display device 100, the reinforcing member 30 that covers the outer shape of the display panel 18 in a planar manner is provided on the back surface thereof. The reinforcing member 30 includes a laminated structure in which two or more carbon fiber layers having different carbon fiber extending directions are laminated.
As described above, carbon fiber is obtained by carbonizing a long fiber made of PAN (polyacrylonitrile), pitch, or the like with high purity at a high temperature of 1000 ° C. or higher, high tensile strength, low thermal deformation rate (low). Linear expansion coefficient) and high thermal conductivity.
That is, since the reinforcing member 30 including carbon fibers having a higher thermal conductivity than the resin is provided on the outer surface (outermost surface) of the resin film 25b, an aluminum reinforcing plate is disposed in the laminate structure. The heat generated by the display panel can be radiated to the outside more efficiently than the display device.
In particular, since the reinforcing member 30 is provided so as to cover the outer shape of the display panel 18 including the display region V that generates the most heat during display, in other words, the entire display panel 18 including the peripheral portion, the heat dissipation is effectively performed. can do.
Furthermore, since the linear expansion coefficient of the reinforcing member 30 is about 1 ppm / ° C., unlike conventional aluminum that has been subjected to intense thermal expansion and contraction, it is possible to prevent the occurrence of warping even when pasted on the entire back surface of the display device 100. it can.
Therefore, it is possible to provide the display device 100 having sufficient heat dissipation and preventing warpage.

In addition, since the tensile strength of the carbon fiber is higher than that of a conventional resin reinforcing plate or aluminum, even if a bending stress is applied in the extending direction of the carbon fiber with the reinforcing member 30 attached thereto. It is possible to suppress the glass substrate from bending to the limit point (limit radius).
In particular, since the reinforcing member 30 covers the peripheral edge of the display panel 18 where cracks are most likely to occur due to bending stress, the occurrence of cracks can be reliably prevented.
Furthermore, the reinforcing member 30 includes a first carbon fiber layer including a plurality of carbon fibers extending in the first direction and a second carbon fiber including a plurality of carbon fibers extending in the second direction intersecting the first direction. Because it includes a laminated structure with a carbon fiber layer, the tensile strength from all directions increases in both directions, and the glass substrate bends to the limit point (limit radius) regardless of the bending stress applied from any direction. This can be suppressed. In addition, the reinforcing member 30 also has a function of deformation restraint and restoration that restores the original shape like a spring.
Therefore, according to the display device 100, sufficient practical strength can be obtained.

Further, since the reinforcing member 30 is provided on the outer surface of the laminate structure 25, the display panel 18 can be made thinner than a conventional display device in which reinforcing plates are attached to the front and back surfaces of the display panel 18. it can. Thereby, since the shape followability of the resin film at the time of lamination becomes good, generation | occurrence | production of the clearance gap to the peripheral part of the display panel 18 can be reduced (prevented). Therefore, it is possible to reduce the gap generated at the peripheral edge of the display panel 18 when laminating, and to obtain a sufficient barrier property against moisture intrusion.
In particular, according to the results of experiments by the inventors, in a preferred example in which the thickness of the display panel 18 is approximately 90 μm and the thickness of the resin films 25a and 25b is approximately 50 μm, Generation of a gap was not recognized.
Therefore, the display device 100 with excellent reliability can be provided.

In addition, unlike the conventional reinforcing structure in which the connecting portion of the flexible substrate 20 is covered and molded with silicon resin (adhesive) or the like, the reinforcing structure is also used by laminating with the resin films 25a and 25b. , Production efficiency is good. Further, since the connection portion and the display panel 18 are bonded (filled) with the same resin, sufficient practical strength (toughness) can be ensured without impairing flexibility.
Furthermore, since the polyethylene-based adhesive layer used for the resin films 25a and 25b is excellent in insulation, water resistance, and heat resistance, sufficient electrical reliability can be ensured.

In addition, in the manufacturing method, the polyethylene-based adhesive layer has almost no initial tackiness at room temperature as seen in the acrylic adhesive layer, so that not only air bubbles are easily removed, but also in the state of a pre-stacked preparation. Positioning can be done easily. Therefore, since a multilayer structure can be formed by a single heat lamination in a reduced pressure atmosphere, manufacturing efficiency is good. Moreover, it is excellent in mass productivity.
Furthermore, since the polyethylene-based adhesive layer has almost no initial adhesion at room temperature, there is little sticking of foreign matter, and even if foreign matter is attached, it can be easily removed. Further, even when there is a foreign matter, when softened by heating, if the foreign matter is small, it is embedded in the adhesive layer, so that defects due to foreign matter contamination can be suppressed as compared with a commonly used acrylic adhesive layer. Moreover, since polyethylene-type resin is general purpose resin, member cost can be held down.

(Embodiment 2)
FIG. 7A is a cross-sectional view of the display device according to the second embodiment, and corresponds to FIG. 7B and 7C are perspective views illustrating one aspect of the reinforcing member according to the second embodiment.
Hereinafter, the display device 110 according to Embodiment 2 of the present invention will be described. In addition, about the component same as Embodiment 1, the same number is attached | subjected and the overlapping description is abbreviate | omitted.
The display device 110 according to the present embodiment includes a reinforcing member 32 having a configuration different from that of the reinforcing member 30 according to the first embodiment. Specifically, a reinforcing member 32 having improved heat dissipation characteristics than the reinforcing member 30 is provided. Other than that, it is substantially the same as the description in the first embodiment.

A reinforcing member 32 is attached to the entire back surface of the laminate structure 25 in the display device 110. The size of the planar reinforcing member 32 is substantially the same as that of the laminate structure 25.
As shown in FIG. 7B, the reinforcing member 32 is formed by laminating and integrating a graphite layer 31 on a reinforcing body 30 made of CFRP having a four-layer structure. The reinforcing body 30 has the same configuration as that of the reinforcing member 30 in the first embodiment. However, in the present embodiment, the reinforcing body 30 is a constituent part of the reinforcing member 32, and hence is referred to as the reinforcing body 30.
The graphite (graphite) layer 31 has a planar hexagonal structure layer made of carbon atoms in the thickness direction (Z-axis direction) as shown in the enlarged view (the circled portion) at the top of FIG. It has a stacked configuration.
Since the graphite layer 31 has an excellent thermal conductivity of 600 to 1500 W / m · k in the plane direction, disposing the layer between the laminate structure 25 and the reinforcing body 30 improves heat dissipation. be able to. Specifically, the heat generated by the display panel 18 is dispersed in the entire graphite layer 31 in a short time and is transferred to the outermost reinforcing body 30, so that the heat dissipation can be improved. The method for producing the graphite layer may be a synthetic graphite crystallized by firing at a temperature of 1000 ° C. or more using a polyimide film as a starting material, or natural graphite obtained by rolling graphite particles produced in a mine or the like to form a film. Since both have a hexagonal crystal structure, a thermal conductivity of 600 W / m · k or more can be obtained. Moreover, the linear expansion coefficient of the graphite layer 31 is about 5 ppm / ° C., which is substantially equivalent to that of the glass substrate.

Moreover, the laminated body which laminated | stacked the reinforcement body 30 and the graphite layer 31 which consist of CFRP is also called CFGRP (Carbon fiber graphite reinforced plastics).
The reinforcing member 32 (CFGRP) can be formed, for example, by superposing a prepreg film (layer) impregnated with carbon fiber with an epoxy intermediate and a graphite film (layer), followed by hot pressing in a reduced pressure atmosphere. it can. In addition, it is preferable that heating temperature is the temperature within the range of 120-150 degreeC.
Further, in the present embodiment, CFRP having a four-layer configuration is adopted as a preferred example, but it is only necessary to include a laminated structure in which two or more carbon fiber layers having different extending directions of carbon fibers are included. This is the same as described in FIG.

Here, the size of the planar graphite layer 31 is smaller than that of the reinforcing body 30. In other words, the periphery of the graphite layer 31 is sized to fit within the reinforcing body 30. Preferably, the size of the graphite layer 31 is larger than the display area V of the display panel 18 and smaller than the outer size of the display panel 18.
This is to make use of the excellent thermal conductivity of the graphite layer 31 and to make up for the wear resistance and brittleness of the layer. It is a device to prevent the hang.

In the present embodiment, as a suitable example, CFGRP having a five-layer structure and a thickness of about 140 μm is used for the reinforcing member 32. Specifically, CFGRP in which a CFRP having a four-layer structure and a thickness of about 100 μm and a graphite layer 31 having a thickness of about 40 μm are stacked is used.
The thickness is not limited to this, and the thickness of the reinforcing member 32 may be a thickness within the range of about 50 to 200 μm. With this thickness, the self-supporting property and strength of the display device 110 and appropriate flexibility can be ensured.
Further, the thickness of the graphite layer 31 is preferably 50 μm or less so as not to impair the thermal conductivity in the thickness direction.

Further, the configuration of the reinforcing member 32 is not limited to the above-described embodiment of FIG. For example, the configuration shown in FIG.
In the reinforcing member 32 of FIG. 7C, an opening (hole) for fitting the graphite layer 31 is formed in the uppermost carbon fiber layer i in the reinforcing body 30. In other words, the uppermost carbon fiber layer i is formed in a frame shape having an opening in which the graphite layer 31 is accommodated.
That is, the reinforcing member 32 has a configuration in which the graphite layer 31 is fitted in the opening. Moreover, the hot press process mentioned above can be used for a manufacturing method.
In the case of this configuration, in order to ensure heat transfer, the thickness of the graphite layer 31 is such that the upper surface of the graphite layer 31 is the same height as the upper surface of the carbon fiber layer i or protrudes from the upper surface of the carbon fiber layer i. Set. As a suitable example, for example, the thickness of the graphite layer 31 is set to about 25 μm, which is the same as the carbon fiber layer i.
According to this configuration, the total thickness of the display device 110 can be reduced while providing substantially the same effects such as heat dissipation as compared with the case of using the reinforcing member of FIG.

As described above, according to the present embodiment, in addition to the effects in the first embodiment, the following effects can be obtained.
According to the display device 110, the reinforcing member 32 in which the reinforcing body 30 made of CFRP and the graphite layer 31 are laminated and integrated is attached to the back surface of the laminate structure 25.
In particular, since the graphite layer 31 having excellent thermal conductivity is disposed between the laminate structure 25 and the reinforcing body 30, the heat generated by the display panel 18 is radially dispersed throughout the graphite layer 31 in a short time. In addition, heat can be transferred to the outermost reinforcing body 30. Then, heat can be radiated from the outermost reinforcing body 30 into the outside air.
Further, the linear expansion coefficient of the graphite layer 31 is about 4 ppm / ° C., which is substantially the same as that of the glass substrate. Therefore, even if the reinforcing member 32 laminated with the reinforcing body 30 made of CFRP is attached to the laminate structure 25, It does not cause warpage.
Therefore, it is possible to provide the display device 110 having sufficient heat dissipation and preventing warpage.

In addition, the thickness of the graphite layer 31 is set to be as thin as 50 μm or less, and the structure is wrapped with the reinforcing body 30 and the resin film 25b so that the peripheral portion is not exposed, so that the thermal conductivity in the thickness direction is not impaired, The wear resistance and brittleness of the layer can be compensated and sufficient practical strength can be ensured.
Therefore, according to the display device 110, sufficient practical strength can be obtained while having flexibility.

(Embodiment 3)
FIG. 8 is a cross-sectional view of the display device according to the third embodiment, and corresponds to FIG.
Hereinafter, the display device 120 according to the third embodiment of the present invention will be described. In addition, about the component same as Embodiment 1 and 2, the same number is attached | subjected and the overlapping description is abbreviate | omitted.
In addition to the configuration of the display device 110 of the second embodiment, the display device 120 of the present embodiment includes a frame-shaped reinforcing member 38 as a second reinforcing member and an optical film 35 on the surface side. Other configurations are the same as those of the display device 110 of the second embodiment. In addition, since the names of the first reinforcing member and the second reinforcing member are for distinguishing both, the reinforcing member 30 is used as the first reinforcing member, and the reinforcing member 38 is used as the second reinforcing member. You may call it. The same applies to each of the following embodiments and modifications.

On the display region V side of the laminate structure 25 in the display device 120, a frame-shaped reinforcing member 38 that surrounds the display region V in a plan view is attached. The frame shape is a configuration that covers the display panel 18 so as to have an opening in the display region V. Furthermore, the shape of the opening of the reinforcing member 38 is provided in a shape along the outline of the display region V, and the end of the reinforcing member 38 preferably covers the end of the display panel 18.
The reinforcing member 38 is formed by laminating and integrating a graphite layer 37 on a reinforcing body 36 made of CFRP having a four-layer structure. The reinforcing body 36 is made of the same material as the reinforcing body 30 of the second embodiment, and the graphite layer 37 is also made of the same material as the graphite layer 31 of the second embodiment, but the planar shape has an opening (hole). It has a frame shape. Further, the size of the planar graphite layer 37 is smaller than that of the reinforcing body 36, and the size of the peripheral edge portion is accommodated in the reinforcing body 36. Further, corners R (see FIG. 11A) are formed at four corners in the opening of the reinforcing member 38 in a plan view. The corner R is formed with a radius of about 1 mm, for example.
Further, the thickness of the reinforcing member 38 and the manufacturing method are the same as those described for the reinforcing member 32.
The reinforcing member 38 may have a configuration in which a graphite layer 37 is fitted into an opening formed in the uppermost carbon fiber layer of the reinforcing body 36, similarly to the configuration of FIG.

An optical film 35 that covers the display region V is attached to the opening (hole) of the reinforcing member 38 on the surface. In addition, in order to improve workability | operativity, the structure which makes the optical film 35 one size larger than an opening part and overlaps the reinforcement member 38 on the peripheral part of the said film may be sufficient (refer FIG. 10).
The optical film 35 is provided for the purpose of reinforcing the strength, protecting the display surface, improving display visibility, and the like.
In the present embodiment, as a suitable example, PET (polyethylene terephthalate) having excellent transparency is used for the optical film 35. Further, an antireflection layer (AR) having a multilayer structure of inorganic oxides having different refractive indexes is formed on the surface, thereby improving display visibility.

The material of the optical film 35 is not limited to PET, and any material having transparency may be used. For example, PEN (polyethylene naphthalate), TAC (triacetyl cellulose), COP (cyclic olefin polymer) or the like is used.
The surface treatment of the optical film 35 is not limited to the antireflection treatment, and various treatments can be performed. For example, a hard coat process for improving wear resistance by forming a hard coat layer such as PMMA, an antireflection process for forming a low antireflective layer (LR) made of a low refractive index fluororesin, and providing unevenness on the surface Surface treatments such as anti-glare treatment, antistatic treatment for forming an antistatic layer to prevent adhesion of dust, and oil repellent treatment for forming an oil repellent layer to which sebum hardly adheres may be performed.

Moreover, the thickness of the optical film 35 is about 20-50 micrometers as a suitable example. This is because a general transparent resin including PET has a large coefficient of linear expansion (20 to 80 ppm / ° C.), expands due to heating during lamination, and shrinks when returning to room temperature, so that the panel after lamination warps. It is. Therefore, by reducing the thickness of the optical film 35 as much as possible, the shape retention force of the reinforcing members 38 and 32 mainly composed of CFRP becomes superior. Therefore, even when the temperature is returned to room temperature, the optical film is less likely to shrink and the panel warps. There is an effect to prevent.
On the other hand, when the thickness is 20 μm or less, surface coating processing such as a hard coat layer and an antireflection layer becomes difficult, and 20 to 50 μm is preferable. This thickness depends on the thickness of the reinforcing members 38 and 32, and it is necessary to make the optical film thinner than the reinforcing member. For example, if the thickness of each reinforcing member is 200 μm, the thickness of the optical film 35 can be in the range of 20 to 100 μm.
The manufacturing method of the display device 120 is basically the same as that described in the flowchart of FIG. 5, but the aspect of the preparation body prepared in step S <b> 1 is different from that of the first embodiment.
Specifically, the resin film 25b, the display panel 18, the resin film 25a, the optical film 35, and the reinforcing member 38 are superposed on the reinforcing member 32 in this order.
In step S3, the preparation is laminated. In other words, all the constituent parts of the display device 120 are laminated and laminated in a lump (times).

In the above description, the thicknesses of the reinforcing member 32 and the reinforcing member 38 are both assumed to be about 100 μm of the four-layer structure of the carbon fiber layer, but are not limited to this thickness.
Since the display device 120 has a configuration in which reinforcing members are arranged on the front and back sides, sufficient practical strength can be ensured even if each thickness is slightly reduced. Therefore, for example, the thickness of both the reinforcing member 32 and the reinforcing member 38 may be about 75 μm of the three-layer structure of the carbon fiber layers. In this case, the thickness of the optical film 35 is preferably about 20 to 50 μm in order to prevent warping of the panel after lamination.
Moreover, if the laminated structure which laminated | stacked two or more carbon fiber layers from which the extension direction of carbon fiber is laminated | stacked is included, you may make thickness of the reinforcement members 32 and 38 still thinner than 50 micrometers. Further, the thickness of the reinforcing member 32 and the thickness of the reinforcing member 38 may be set to different thicknesses.

As described above, according to the present embodiment, in addition to the effects in the second embodiment, the following effects can be obtained.
According to the display device 120, the frame-shaped reinforcing member 38 is provided on the surface of the laminate structure 25 in addition to the reinforcing member 32 on the back surface of the laminate structure 25.
Therefore, even if bending stress is applied from any direction, the glass substrate can be prevented from bending to the limit point (limit radius). In particular, since the peripheral portion of the display panel 18 that is most likely to crack is wrapped from the front and back surfaces by the two reinforcing members, the display panel 18 can be more reliably prevented from cracking.
In addition, since the corners R are formed at the four corners of the opening of the reinforcing member 38, it is possible to suppress the occurrence of cracks when bending stress is applied compared to the case where the four corners are edges. it can.
Accordingly, it is possible to provide the display device 120 that has both flexibility and practical strength (toughness).

Furthermore, the heat generated by the display panel 18 can be efficiently radiated by the two reinforcing members on the front and back surfaces. In particular, since the graphite layer 37 is disposed between the laminate structure 25 and the reinforcing body 36 also on the surface side, the heat generated on the surface side of the display panel 18 can be efficiently radiated.
Therefore, the display device 120 having both flexibility, practical strength (toughness), and heat dissipation can be provided.
Moreover, according to the display apparatus 120, the optical film 35 which covers the display area V is attached to the surface.
Therefore, the display surface can be protected and the toughness can be improved. Moreover, display visibility can be improved.

(Embodiment 4)
FIG. 9A is a cross-sectional view of a display device according to Embodiment 4, and corresponds to FIG. FIG.9 (b) is a perspective view which shows the one aspect | mode of the reinforcing member which concerns on Embodiment 4, and respond | corresponds to FIG.7 (b).
Hereinafter, the display device 130 according to Embodiment 4 of the present invention will be described. In addition, about the component same as Embodiment 3, the same number is attached | subjected and the overlapping description is abbreviate | omitted.
The display device 130 according to the present embodiment includes reinforcing members on the front and back surfaces, respectively, similarly to the display device 120 according to the third embodiment, but the laminated structure of the reinforcing members is different from that of the third embodiment. Other configurations are the same as those of the display device 120 of the third embodiment.

The display device 130 includes a frame-shaped reinforcing member 39 on the surface of the laminate structure 25 and a plate-shaped reinforcing member 33 on the back surface. Moreover, the optical film 35 which covers the display area V is attached to the surface.
The reinforcing members 33 and 39 have the same planar shape and thickness as the reinforcing members 32 and 38 in the third embodiment, but have different laminated structures.
As shown in FIG. 9B, the reinforcing member 33 is formed by laminating a reinforcing body 30 made of CFRP having a four-layer structure and a graphite layer 31 so as to be integrated. Specifically, the graphite layer 31 is sandwiched between the second carbon fiber layer i and the third carbon fiber layer h from the bottom in the CFRP four-layer configuration. In other words, the graphite layer 31 is wrapped from the front and back surfaces by a laminated structure in which two carbon fiber layers having different carbon fiber extending directions are laminated.

In addition, it is not limited to this laminated structure, What is necessary is just the structure which sandwiches the graphite layer 31 between any carbon fiber layers in a plurality of carbon fiber layers. Similarly to the description in the first embodiment, the reinforcing body 30 only needs to include a laminated structure in which two or more carbon fiber layers having different carbon fiber extending directions are laminated.
The manufacturing method of the reinforcing members 33 and 39 and the manufacturing method of the display device 130 are the same as those described in the above embodiment.

As described above, according to the present embodiment, the following effects can be obtained.
The reinforcing members 33 and 39 include graphite layers 31 and 37 having excellent thermal conductivity in a laminated structure made of CFRP. Therefore, it has higher heat dissipation than a reinforcing member composed only of CFRP. In particular, according to the results of experiments by the inventors, it has been confirmed that the heat dissipation is substantially the same as that of the reinforcing members 32 and 38 of the third embodiment.
Therefore, since the same effect as the effect in Embodiment 3 can be obtained, the display device 130 having both flexibility, practical strength (toughness), and heat dissipation can be provided.

(Embodiment 5)
FIG. 10A is a cross-sectional view of the display device according to the fifth embodiment, and corresponds to FIG. FIG.10 (b) is a perspective view which shows the one aspect | mode of the reinforcing member which concerns on Embodiment 5, and respond | corresponds to FIG.9 (b).
Hereinafter, the display device 140 according to Embodiment 5 of the present invention will be described. In addition, about the component same as Embodiment 4, the same number is attached | subjected and the overlapping description is abbreviate | omitted.
The display device 140 according to the present embodiment includes reinforcing members on the front and rear surfaces in the same manner as the display device 130 according to the fourth embodiment, but the structure of the reinforcing member is different from that of the fourth embodiment. Specifically, the reinforcing member 44 on the surface does not include a graphite layer. In addition, the reinforcing member 43 on the back surface uses a graphite layer 41 in which a plurality of holes are formed. Other configurations are the same as those of the display device 130 of the fourth embodiment.

The display device 140 includes a frame-shaped reinforcing member 44 on the surface of the laminate structure 25 and a plate-shaped reinforcing member 43 on the back surface. Moreover, the optical film 35 which covers the display area V is attached to the surface.
First, the reinforcing member 44 is obtained by removing the graphite layer from the configuration of the reinforcing member 39 of the fourth embodiment. In other words, the CFRP is obtained by pressing the reinforcing member 30 of FIG. 4 into a frame shape.
The reinforcing member 43 has the same planar shape, thickness, and stacking order (structure) as the reinforcing member 33 of the fourth embodiment, but uses a graphite layer 41 of a different form.
Specifically, the graphite layer 41 is obtained by forming a plurality of holes in a graphite layer having substantially the same size as the reinforcing member 43 in a plan view. In the present embodiment, as a preferred example, holes having a diameter of about 5 mm are disposed on the entire surface of the graphite layer 41 at a pitch of about 10 mm. Note that the present invention is not limited to this value, and the hole diameter and the arrangement pitch may be appropriately determined according to the size of the display device 140.
Further, such a graphite layer 41 can be easily formed from, for example, a large graphite sheet using a press die or a Thomson die.

About the manufacturing method of the reinforcement member 43, and the manufacturing method of the display apparatus 140, it is the same as that of the description in the said embodiment.
Here, when the reinforcing member 43 is formed using hot pressing, a portion covering the hole portion of the graphite layer 41 has a concave shape on the back surface (outermost surface) of the reinforcing member 43 as shown in FIG. Thus, a concavo-convex shape in which the other portions are convex is formed. This is because, in the portion covering the hole, the second carbon fiber layer i and the third carbon fiber layer h are directly bonded by, for example, a thermosetting epoxy resin.

As described above, according to the present embodiment, in addition to the effects in the fourth embodiment, the following effects can be obtained.
According to the display device 140, the reinforcing member 43 having a configuration in which the graphite layer 41 in which a plurality of holes are formed is sandwiched from the front and back surfaces by the carbon fiber layer is provided. Thereby, in the part which covers a hole part, since the carbon fiber layer of the front and back is adhere | attached directly, the interlayer intensity | strength of the graphite layer 41 can be supplemented and the practical strength (toughness) of the reinforcement member 43 can be improved. . Furthermore, since the concavo-convex shape is formed on the back surface (outermost surface) of the reinforcing member 43, the surface area of the back surface serving as the heat radiating surface is increased, and heat dissipation is improved.
Further, since the graphite layer 41 is substantially the same size as the reinforcing member 43 in a plan view, a large-sized reinforcing member is formed by laminating a large-sized carbon fiber layer and a large-sized graphite layer. A manufacturing method of cutting out the single reinforcing member 43 can be adopted. In other words, it is possible to adopt a manufacturing method in which a single reinforcing member 43 is cut from a large reinforcing member having a plurality of reinforcing members imposed by using a brace process or the like. Therefore, manufacturing efficiency can be increased. Further, the manufacturing cost can be suppressed.
Therefore, it is possible to provide the display device 140 having both flexibility, practical strength (toughness), and heat dissipation.

(Electronics)
11A and 11B are perspective views illustrating an electronic book on which the above-described display device is mounted, in which FIG. 11A is a perspective view of a display device that forms a page, and FIG. 11B is a perspective view of the electronic book.
The display device 140 described above can be used by being mounted on an electronic book 150 as an electronic device, for example. In addition, you may replace the display apparatus 140 with the display apparatus in each embodiment and a modification.

In FIG. 11A, the display device 140 is arranged so that the display region V is vertically long. In addition, binding holes h <b> 1 and h <b> 2 are formed at both ends of the reinforcing member 30 on the flexible substrate 20 side in order to bind the electronic book.
As shown in FIG. 11B, the electronic book 150 includes a main body 50, a hinge part 51, rings 52 and 53, a circuit part 54, an operation part 55, and the like.
The main body 50 is a file (binder) and includes front and back mount portions that are openable and closable.
The hinge portion 51 is disposed at a joint portion between the front and back mount portions and includes rings 52 and 53. Moreover, the hinge part 51 is formed so that opening and closing is possible, and the rings 52 and 53 are also opened and closed in synchronization with the opening and closing.

When the hinge 51 is opened, the rings 52 and 53 are also opened. In this state, the ring is passed through the binding holes h1 and h2, and the display device 140 is bound into the electronic book 150. At this time, the three flexible boards 20 are inserted into connectors formed inside the hinge portion 51. The connector is connected to the circuit unit 54. And the hinge part 51 is closed. FIG. 11B shows a state in which the display device 140 is bound in the electronic book 150 in this way. Further, a plurality of display devices 140 can be bound.
In addition, an operation unit 55 including a touch panel is provided on the front mount portion, and a desired image can be displayed on the display device 140 by touching the operation unit 55 with the operation pen 57 or a finger. .
The circuit unit 54 disposed inside the hinge unit 51 includes a rechargeable power source unit such as a lithium ion battery, an image processing unit that generates image data to be supplied to the display device 140, and various display modes by the electronic book 150. A storage unit that stores programs and data that define the control unit, a control unit that controls each unit according to the program and data, or the operation content to the operation unit 55, an interface unit that receives an image signal by connecting to an external device, etc. It is included.

For example, when the display device 140 is turned as in the case of reading a book by turning an operation by setting the operation unit 55, a continuous page image may be displayed on the display device 140 that is sequentially opened. it can. In this display mode, the display device 140 that is closed (overlapped) is turned off to suppress power consumption.
Each page of the electronic book 150 uses the display device 140 having flexibility, so that images and sentences can be smoothly enjoyed while turning the page like a book. Further, since the display device 140 has a sufficient practical strength (toughness), it can be handled in the same manner as a normal book.
Therefore, the electronic book 150 that can be handled in the same manner as a normal book can be provided.

  Further, the electronic device is not limited to the electronic book 150 and may be an electronic device provided with a display unit. For example, a mobile phone may be used. Specifically, it may be an integrated mobile phone, a foldable mobile phone, or a slide mobile phone. Alternatively, it can be used in various electronic devices such as a display device for a car navigation system, a PDA (Personal Digital Assistants), a mobile computer, a digital camera, a digital video camera, an in-vehicle device, and an audio device.

  Note that the present invention is not limited to the above-described embodiment, and various modifications and improvements can be added to the above-described embodiment. A modification will be described below.

(Modification 1)
This will be described with reference to FIG.
In each of the above embodiments, the display panel 18 has been described as having a configuration in which a color filter that emits white light in common to all pixels and selectively transmits each color light of RGB from white light is provided on the display surface side. However, the present invention is not limited to this. Any color pixel may be used as long as it can emit RGB color light.
For example, a display panel having a configuration using a so-called three-color coating method in which a light emitting layer of each color of RGB is formed for each color pixel of RGB in the organic EL layer 8 may be used.
Further, in each of the above embodiments, the display device 100 has been described as an active matrix type, but may be a passive (simple) matrix type.
In this case, the element layer 2 becomes unnecessary, and the organic EL layer 8 is sandwiched between the scan electrode and the data electrode. For example, the scan electrode is formed on the element substrate 1 side, and the data electrode is formed on the CF substrate 16 side. The scan electrodes and the data electrodes are formed so as to extend in the intersecting directions so as to have a lattice shape in plan view.
Even if it is these structures, the effect similar to said each embodiment can be acquired.

(Modification 2)
This will be described with reference to FIG.
In Embodiment 5 described above, CFRP containing carbon fiber is used as the reinforcing member 44, but is not limited thereto. Any material having similar physical properties may be used. The same applies to the reinforcing member 30 of the first embodiment.
For example, the reinforcing member 44 may be configured by using invar having a physical property close to that of CFRP (an iron alloy having a Ni content of 30 to 50%), titanium, a titanium alloy, or the like.
In particular, by using the invar having excellent workability for the frame-shaped reinforcing member 44 on the surface, the four corners R (see FIG. 11A) of the opening and the opening end face can be smoothly finished. A function as a parting plate can be added to partition the display region V and make it stand out in the reinforcing member 44. Even with these configurations, the same effects as those of the above-described embodiments can be obtained.

(Modification 3)
FIG. 12 is a cross-sectional view of a display panel according to Modification Example 3, and corresponds to FIG.
In each said embodiment, although the display panel 18 demonstrated as what is an organic electroluminescent panel, it is not limited to this. Any thin display panel in which an electro-optic layer is sandwiched between a pair of substrates may be used. For example, an electrophoretic panel including an electrophoretic layer may be used as the electro-optical layer.
Hereinafter, the display panel 68 according to Modification 3 will be described. In addition, about the component same as FIG. 3, the same number is attached | subjected and the overlapping description is abbreviate | omitted.
The display panel 68 of the present embodiment is a reflective electrophoretic panel provided with an electrophoretic layer 67 as an electro-optical layer.

The display panel 68 has a configuration in which an electrophoretic layer 67 is sandwiched between the element substrate 1 and the counter substrate 65. Further, the laminated structure from the element substrate 1 to the pixel electrode 6 is the same as the configuration of FIG.
The counter substrate 65 is a transparent substrate made of, for example, glass or plastic. On the element substrate 1 side of the counter substrate 65, a counter electrode 64 is formed on the entire surface (solid shape) so as to face the plurality of pixel electrodes 6. The counter electrode 64 is made of a transparent conductive material such as ITO.
The electrophoretic layer 67 includes a plurality of microcapsules 70, a binder 62 that holds the plurality of microcapsules 70, and an adhesive layer 61. The display panel 68 includes an electrophoretic sheet in which an electrophoretic layer 67 is fixed to the counter substrate 65 side in advance by a binder 62, and the element substrate 1 on which the pixel electrode 6 and the like are formed separately from the sheet. Are formed by adhering with an adhesive layer 61.

One or a plurality of microcapsules 70 are sandwiched between the pixel electrode 6 and the counter electrode 64, and are arranged in one pixel (in other words, with respect to one pixel electrode 6).
As shown in the enlarged view in the upper right of FIG. 12, the microcapsule 70 has a configuration in which a dispersion medium 71, a plurality of white particles 72, and a plurality of black particles 73 are enclosed in a coating 75. The microcapsule 70 is formed in a spherical shape having a particle size of about 50 μm, for example.
The coating 75 is made of a polymer resin having translucency such as acrylic resin, urea resin, gum arabic, and gelatin.
The dispersion medium 71 is a medium for dispersing the white particles 72 and the black particles 73 in the microcapsules 70 (in other words, in the coating film 75).

The white particles 72 are particles (polymer or colloid) made of a white pigment such as titanium dioxide, zinc white (zinc oxide), or antimony trioxide, and are negatively charged, for example.
The black particles 73 are particles (polymer or colloid) made of a black pigment such as aniline black or carbon black, and are positively charged, for example.
As a result, the white particles 72 and the black particles 73 move in the dispersion medium 71 due to the electric field (potential difference) generated by the potential difference between the pixel electrode 6 and the counter electrode 64, so that the particles gathered on the counter electrode 64 side. The color tone will be displayed.
In addition, color display of red, green, blue, etc. can also be performed by changing the pigment used for the white particle 72 and the black particle 73 to pigments, such as red, green, and blue, for example.
In addition, the present invention is not limited to the above-described microcapsule method, and an electropowder fluid type electrophoretic panel that controls display switching / on / off by switching between plus and minus by putting a charged electropowder fluid in a pixel. It may be. Alternatively, an electrophoretic panel using cholesteric liquid crystal may be used.
Even if it is these structures, the effect similar to said each embodiment can be acquired.

  DESCRIPTION OF SYMBOLS 1 ... Element board | substrate as a glass substrate, 8 ... Organic EL layer as an electro-optic layer, 16 ... CF board | substrate as a glass substrate, 18 ... Display panel, 20 ... Flexible substrate, 25a, 25b ... Resin film, 30, 32, 33, 43: Reinforcing member as a first reinforcing member, 31, 41: Graphite layer, 35: Optical film, 38, 39, 44 ... Reinforcing member as a second reinforcing member, 100, 110, 120, 130, 140 ... A display device as an electro-optical device, 150 ... an electronic book as an electronic device, h ... a carbon fiber layer as a first carbon fiber layer, i ... a carbon fiber layer as a second carbon fiber layer, V ... a display region.

Claims (15)

A display panel having an electro-optic layer sandwiched between a pair of glass substrates;
A resin film laminated so as to cover the first surface on the display area side of the display panel and the second surface opposite to the first surface;
A reinforcing member is provided on at least the resin film covering the second surface,
The reinforcing member includes a first carbon fiber layer including a plurality of carbon fibers extending in a first direction in a plane and a plurality of carbon fibers extending in a second direction intersecting the first direction. An electro-optical device comprising a laminated structure including a second carbon fiber layer.   The electro-optical device according to claim 1, wherein the reinforcing member includes a graphite layer.   The electro-optical device according to claim 2, wherein the graphite layer is disposed between the resin film covering the second surface and the first carbon fiber layer.   The electro-optical device according to claim 2, wherein the graphite layer is disposed between the first carbon fiber layer and the second carbon fiber layer.   The electro-optical device according to claim 2, wherein the graphite layer has a plurality of holes formed in a plane. The first carbon fiber layer and the second carbon fiber layer are formed of a prepreg obtained by impregnating carbon fiber with a resin,
The said reinforcement member is a laminated body which laminated | stacked and hardened 3 or more layers of the said 1st carbon fiber layer and the said 2nd carbon fiber layer, It is any one of Claim 1 thru | or 5 characterized by the above-mentioned. The electro-optical device described. When the reinforcing member is the first reinforcing member,
A second reinforcing member provided on the resin film covering the first surface;
The electro-optical device according to claim 1, wherein the second reinforcing member is formed to have an opening in the display panel. The opening shape of the second reinforcing member is provided in the same shape as the display area,
The electro-optical device according to claim 7, wherein the second reinforcing member is sized to cover up to an end of the display panel in a planar manner.   9. The electro-optical device according to claim 7, wherein the second reinforcing member includes a laminated structure or an invar of the first carbon fiber layer and the second carbon fiber layer.   The electro-optical device according to claim 1, wherein each of the glass substrates has a thickness of 100 μm or less.   The electro-optical device according to claim 1, wherein the resin film is a polyethylene copolymer material. The opening of the second reinforcing member is provided with an optical film that covers the display area,
The electro-optical device according to claim 7, wherein the resin film functions as an adhesive that bonds the display panel, the second reinforcing member, and the optical film. The display panel is formed with an overhang region in which one side of the glass substrate out of the pair of glass substrates overhangs the other glass substrate,
One end of a flexible printed circuit board is connected to the overhang region,
13. One end of the flexible printed circuit board is covered with the resin film, and the other end of the flexible printed circuit board is exposed to the outside from an end of the resin film. The electro-optical device according to any one of the above.   The electro-optical device according to claim 1, wherein the electro-optical layer is an organic EL layer including an organic light emitting layer.   An electronic apparatus comprising the electro-optical device according to claim 1 as a display unit.

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