JP6324020B2 - Display device manufacturing method and manufacturing apparatus - Google Patents

Description

  The present invention relates to a display device manufacturing method and a manufacturing apparatus that perform processing using an ultraviolet curable resin.

  With the spread of information electronic devices in recent years, thin and lightweight liquid crystal display devices are used as displays for mobile phones or personal computers, devices used in industrial applications, in-vehicle display devices, handy terminals, and advertisement displays. ing.

  Further, in recent years, display devices in which an input device such as a touch panel is provided on the front surface of a liquid crystal panel and a transparent protective plate is provided on the front surface of the input device have been widely used. The display device is a ticket terminal or a display device of an ATM (Automated Teller Machine), a mobile terminal such as a mobile phone or a tablet PC (Personal Computer). The transparent protective plate is a plate for protecting the screen of the input device.

  Among these display devices, there is one in which a liquid crystal display device and a transparent member such as a touch panel and a transparent protective plate are joined (bonded) with a transparent resin. The transparent resin has a refractive index substantially equal to that of a transparent member such as a touch panel or a transparent protective plate. With this configuration, it is possible to eliminate the reflection of the surface between the members and obtain good visibility.

  Patent Document 1 discloses a technique (hereinafter also referred to as related technique A) in which a display panel and a protective plate (front window) are joined with an ultraviolet curable resin. Specifically, in Related Art A, the display panel and the protective plate disposed on the front surface of the display panel are bonded with an ultraviolet curable resin.

  Next, both members of the display panel and the protection plate to be joined are set at predetermined positions by the positioning device (support mechanism). Next, the protective plate is irradiated with ultraviolet rays through a mask that limits the range through which the ultraviolet rays are transmitted. Thereby, only a part of the joint surface (ultraviolet curable resin) between the display panel and the protective plate is cured.

  Next, both members to be joined are removed from the positioning device, and then the entire ultraviolet curable resin is cured by irradiation with ultraviolet rays. Thereby, the occupation time of the apparatus (support mechanism) used for positioning can be shortened, and productivity can be improved.

  Patent Document 2 discloses a technique (hereinafter also referred to as related technique B) in which a display panel and a protective plate are joined with an ultraviolet curable resin having an appropriate elongation rate. With Related Technology B, it is possible to suppress the occurrence of display unevenness in the display device due to the influence of stress caused by curing shrinkage of the ultraviolet curable resin, warpage of the protective plate, and the like.

JP 2011-145534 A JP 2009-186963 A

  However, the related technologies A and B have the following problems. Specifically, in the related art A, in order to cure only a part of the ultraviolet curable resin, after the first irradiation step of irradiating the ultraviolet ray, the second surface of the protective plate (front window) is irradiated with the ultraviolet ray. An irradiation process is performed. As a result, the entire ultraviolet curable resin is cured.

  In the second irradiation step, since the ultraviolet ray is irradiated on the entire surface of the ultraviolet curable resin, the ultraviolet curable resin contracts. Therefore, while maintaining the distance between the two members to be joined by the spacer, between the part of the ultraviolet curable resin previously cured in the first irradiation process and the other part of the ultraviolet curable resin cured in the second irradiation process. Stress is generated. As a result, the display panel is deformed, and there is a high possibility that display unevenness occurs in the display device.

  In Related Art B, a soft bonding resin is used as the ultraviolet curable resin for bonding the display panel and the protective plate. Thereby, generation | occurrence | production of the stress by shrinkage | contraction of resin, the curvature of a protection board, etc. can be relieved to some extent.

  However, when the ultraviolet curable resin used is too soft, there is a risk that after the ultraviolet curable resin is cured, problems such as positional displacement between bonded members, damage to the joint surface due to external forces such as vibration and impact, etc. may occur. .

  The present invention has been made to solve such a problem, and a method of manufacturing a display device capable of suppressing the occurrence of defects caused by an ultraviolet curable resin used for joining display panels. The purpose is to provide.

In order to achieve the above object, a method for manufacturing a display device according to one embodiment of the present invention includes a display panel that displays an image, and a surface of the display panel that displays the image, and transmits ultraviolet light. It is a manufacturing method of a display apparatus provided with a transparent member. In the state where the display panel and the transparent member are bonded to each other by the ultraviolet curable resin that is cured by being irradiated with the ultraviolet light, the display device manufacturing method includes : Until the entire area in a plan view is irradiated with the ultraviolet light, the position of the irradiation area irradiated with the ultraviolet light is changed from the central part of the display surface for displaying the image of the transparent member to the periphery of the display surface. An ultraviolet irradiation step of irradiating the ultraviolet rays while continuously moving to the part .

  According to the present invention, in a state where the display panel and the transparent member are bonded with an ultraviolet curable resin, the ultraviolet ray is irradiated until the ultraviolet ray is irradiated to the entire region in a plan view of the ultraviolet curable resin. The ultraviolet ray is irradiated while continuously changing the position of the irradiated region from the first region which is a part of the display surface of the transparent member to the second region which is another part of the display surface.

  That is, in the present invention, as in the conventional case, the entire surface of the ultraviolet curable resin is not irradiated with ultraviolet light, and the ultraviolet light is irradiated to a part of the ultraviolet curable resin while the position of the irradiation region is changed. Therefore, the portion cured by the ultraviolet light that passes through the transparent member continuously spreads from a partial region of the ultraviolet curable resin to the entire region of the ultraviolet curable resin. That is, until the entire region of the ultraviolet curable resin is cured, the uncured ultraviolet curable resin exists around the region where the curing proceeds by the ultraviolet rays in the entire region of the ultraviolet curable resin.

  Thereby, the uncured ultraviolet curable resin is always supplemented in the region where the curing proceeds. As a result, the generation of stress between the display panel and the transparent member can be sufficiently suppressed until the entire region of the ultraviolet curable resin is cured. Therefore, it is possible to suppress the occurrence of defects due to the ultraviolet curable resin used for joining the display panels.

1 is an exploded perspective view of a display device according to Embodiment 1 of the present invention. It is sectional drawing of the display apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the ultraviolet irradiation device used at the ultraviolet irradiation process which concerns on Embodiment 1 of this invention. It is a figure for demonstrating the ultraviolet irradiation process which concerns on Embodiment 1 of this invention. It is a figure for demonstrating the ultraviolet irradiation process which concerns on Embodiment 2 of this invention. It is a figure for demonstrating the manufacturing method of the display apparatus based on a comparative example. It is a figure for demonstrating the stress which generate | occur | produces with cured resin.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof may be omitted.

  It should be noted that the dimensions, materials, shapes, relative arrangements, and the like of the constituent elements exemplified in the embodiments are appropriately changed depending on the configuration of the apparatus to which the present invention is applied and various conditions. It is not limited to those examples. Moreover, the dimension of each component in each figure may differ from an actual dimension.

<Comparative example>
Hereinafter, a comparative example using an ultraviolet curable resin for joining display panels will be described. The ultraviolet curable resin is a resin that cures a portion of the ultraviolet curable resin that has been irradiated with ultraviolet rays when the ultraviolet curable resin is irradiated with ultraviolet rays. Hereinafter, the uncured ultraviolet curable resin is also referred to as an ultraviolet curable resin J10. The ultraviolet curable resin J10 has fluidity. Moreover, the ultraviolet curable resin J10 is transparent.

  FIG. 6 is a diagram for explaining a method of manufacturing a display device according to a comparative example. Hereinafter, the method for manufacturing a display device according to the comparative example is also referred to as a manufacturing method N. In the manufacturing method N, the joining process N which joins the display panel 10 and the transparent member 50 is performed.

  The display panel 10 is a liquid crystal panel, for example. The display panel 10 displays an image. The peripheral edge of the display panel 10 is in contact with the housing 3.

  The transparent member 50 is a member that transmits ultraviolet rays. The transparent member 50 is a touch panel, a transparent protective plate, or the like. The transparent member 50 has a display surface 50a. The display surface 50a displays an image by the image light constituting the image displayed on the display panel 10 being transmitted through the ultraviolet curable resin J10 and the transparent member 50.

  Referring to FIG. 6, in joining process N, first, ultraviolet curable resin J <b> 10 is filled (applied) between transparent member 50 and display panel 10. The cured ultraviolet curable resin J10 has a refractive index equivalent to that of the display panel 10 and the transparent member 50.

  Specifically, the bonding process N includes a resin supply process N and an ultraviolet irradiation process N. In the joining process N, first, a resin supply process N is performed. In the resin supply process N, the ultraviolet curable resin J10 is filled so that the ultraviolet curable resin J10 spreads over the entire one surface of the transparent member 50 between the transparent member 50 and the display panel 10. Then, the thickness of the ultraviolet curable resin J10 is controlled to a desired thickness.

  Next, the ultraviolet irradiation process N is performed. In the ultraviolet irradiation step N, the entire display surface 50a is irradiated with ultraviolet rays. Thereby, ultraviolet rays are irradiated to the entire upper surface of the ultraviolet curable resin J10. Therefore, the entire ultraviolet curable resin J10 is cured. As a result, the display panel 10 and the transparent member 50 are joined.

  In the following description, the ultraviolet curable resin J10 that has been cured to the maximum by irradiation with ultraviolet rays is also referred to as a cured resin J10a. The cured resin J10a is transparent. In the following description, a region of the entire ultraviolet curable resin J10 that has been cured to the maximum when irradiated with ultraviolet rays is also referred to as a cured region R5. The ultraviolet curable resin J10 in the cured region R5 is a cured resin J10a.

  Next, the stress generated by the curing of the ultraviolet curable resin J10 will be described. FIG. 7 is a diagram for explaining the stress generated by the cured resin J10a. A region R11 in FIG. 7 is a region where stress is generated.

  With reference to FIGS. 6 and 7, when ultraviolet irradiation is performed in the ultraviolet irradiation step N described above, the curing of the ultraviolet curable resin J10 gradually proceeds. Along with this, the fluidity of the ultraviolet curable resin J10 decreases. When the ultraviolet curable resin J10 is cured to a certain hardness, the fluidity of the ultraviolet curable resin J10 is lost.

  However, in order to completely cure the ultraviolet curable resin J10, it is necessary to further irradiate the ultraviolet curable resin J10 with ultraviolet rays in the ultraviolet irradiation step N.

  After the ultraviolet curable resin J10 loses its fluidity, the ultraviolet curable resin J10 contracts due to curing due to further ultraviolet irradiation, and the ultraviolet curable resin J10 interposed between the display panel 10 and the transparent member 50 is caused. Decrease in volume. The ultraviolet curable resin J10 having a reduced volume is a cured resin J10a.

  Thereby, with respect to the peripheral part of the cured resin J10a whose position in the thickness direction is regulated by the housing 3, a stress is generated in the central part of the cured resin J10a. Specifically, in the central portion of the curable resin J10a, stress is generated in the region R11 so that the display panel 10 and the transparent member 50 come closer to each other due to the decrease in volume.

  As a result, there is a problem in that display unevenness due to deformation of the display panel 10 occurs, or peeling occurs between the bonded member such as the display panel 10 and the cured resin J10a.

  Therefore, the following embodiment solves the problem described in the comparative example, that is, the problems of the related technologies A and B. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1>
(Overall configuration of display device)
FIG. 1 is an exploded perspective view of a display device 100 according to Embodiment 1 of the present invention. In FIG. 1, the X, Y, and Z directions are orthogonal to each other. The X, Y, and Z directions shown in the following figures are also orthogonal to each other.

  Hereinafter, a direction including the X direction and the direction opposite to the X direction (−X direction) is also referred to as an X-axis direction. In the following, the direction including the Y direction and the direction opposite to the Y direction (−Y direction) is also referred to as a Y-axis direction. In the following, a direction including the Z direction and a direction opposite to the Z direction (−Z direction) is also referred to as a Z-axis direction. In the following, a plane including the X axis and the Y axis is also referred to as an XY plane.

  FIG. 2 is a cross-sectional view of display device 100 according to Embodiment 1 of the present invention. Specifically, FIG. 2 shows a cross-sectional view of the display device 100 along the line A1-A2 of FIG. The display device 100 is a liquid crystal display device.

  The display device 100 is not limited to a liquid crystal display device, and may be another type of display device. The display device 100 may be, for example, an organic EL (Electroluminescence) display.

  As shown in FIGS. 1 and 2, the display device 100 includes a display panel 10, a backlight 20, a housing 3, a touch panel 4, a circuit board 5, and a transparent protective plate 6.

  The display panel 10 is a liquid crystal panel, for example. The display panel 10 displays an image. The backlight 20 irradiates light to the back surface of the display panel 10.

  A display panel 10 and a backlight 20 are disposed inside the housing 3. The housing 3 has an opening 3H.

  The touch panel 4 is a transparent member that transmits ultraviolet rays. The touch panel 4 is provided on the surface side of the display panel 10 on which video is displayed. That is, the touch panel 4 is disposed on the display panel 10 and the housing 3. The touch panel 4 detects an input signal from the outside.

  The touch panel 4 has surfaces 4a and 4b. The surface 4a is a surface opposite to the surface 4b. The surface 4 a is a surface on the side where the user operates the touch panel 4. The touch panel 4 and the display panel 10 are joined by the cured resin J10a obtained by curing the ultraviolet curable resin J10.

  Moreover, the image light which comprises the image | video which the display panel 10 displays transmits the hardening resin J10a and the touch panel 4 (transparent member), and the surface 4a displays an image | video. Note that the touch panel 4 and the display panel 10 are joined to each other over almost the entire display area where the video is displayed.

  The transparent protective plate 6 is a plate that protects the touch panel 4. The transparent protective plate 6 is a transparent member that transmits ultraviolet rays. The transparent protective plate 6 is provided on the side of the display panel 10 on which a video is displayed. Specifically, the transparent protective plate 6 is provided on the surface 4 a side of the touch panel 4.

  The touch panel 4 and the transparent protective plate 6 are joined by the cured resin J10a obtained by curing the ultraviolet curable resin J10. Note that the touch panel 4 and the transparent protective plate 6 are joined to each other over almost the entire display area where the video is displayed.

  The display device 100 may be configured not to include the transparent protective plate 6. Further, the display device 100 may have a configuration that does not include the touch panel 4 (hereinafter also referred to as a modified configuration A). In the display device 100 having the modified configuration A, the display panel 10 and the transparent protective plate 6 are joined by the cured resin J10a.

  Next, each of the members constituting the display device 100 will be described in more detail.

(Display panel)
The display panel 10 is a transmissive or transflective liquid crystal panel. The display panel 10 displays an image by applying the birefringence of the liquid crystal. The display panel 10 includes a substrate 11, a substrate 12, and a driving IC (Integrated Circuit) 13.

  The substrate 11 is a substrate in which a colored layer, a light shielding layer, a counter electrode, and the like are formed on an insulating substrate such as glass. The substrate 12 is a substrate in which pixel electrodes using switching elements are formed in a matrix on an insulating substrate such as glass. The switching element is a thin film transistor. Hereinafter, the thin film transistor is also simply referred to as a TFT.

  The driving IC 13 is arranged on the peripheral portion of the substrate 12 or a tape-like wiring material connected to the peripheral portion of the substrate 12. The wiring material is TCP, COF, or the like.

  Further, the display panel 10 is provided with a spacer, a sealing material, a liquid crystal, a sealing material, an alignment film, a polarizing plate, and the like. The spacer holds the distance between the substrate 11 and the substrate 12. The sealing material bonds the substrate 11 and the substrate 12 together. The liquid crystal is provided between the substrate 11 and the substrate 12. The sealing material is a member that seals the liquid crystal. The sealing material is provided with an inlet for injecting liquid crystal. The alignment film is a film that distributes liquid crystal light. The polarizing plate is disposed on the outer surfaces of the substrate 11 and the substrate 12.

(Backlight)
The backlight 20 irradiates the display panel 10 with light from the substrate 12 side. The backlight 20 includes a light source 25, a light guide plate 23, an optical sheet 22, a reflection sheet 24, a back casing 26, and a front casing 21.

  The light source 25 emits light. The light guide plate 23 propagates the light emitted from the light source 25. The optical sheet 22 controls the distribution and spread of the light emitted from the light guide plate 23. The reflection sheet 24 reflects light emitted from the back surface of the light guide plate 23 toward the display surface. The light source 25, the light guide plate 23, the optical sheet 22, and the reflection sheet 24 are accommodated in the rear casing 26.

  The light source 25 is a point light source such as an LED (Light Emitting Diode) or a laser diode. The light source 25 is mounted on the light source substrate 25a. The light source 25 is not limited to the point light source 25a mounted on the light source substrate 25a, and may be configured using a linear light source such as a CCFL (cold cathode tube).

  The light source substrate 25a is a substrate configured based on a general glass epoxy resin, a substrate using a flexible flat cable, or the like. The light source substrate 25a may be a substrate configured based on a metal such as aluminum or ceramic in order to improve heat dissipation.

  When the light source 25 is a point light source such as an LED, the point light source emits yellow light by an element that emits monochromatic light such as red, green, and blue, an element that emits blue light, and the blue light. There is an element that emits pseudo white light made of a phosphor. In the present embodiment, the light source 25 is described as an example of a point light source (LED) that emits pseudo white light.

  The light guide plate 23 is made of transparent acrylic resin, polycarbonate resin, glass or the like. The light guide plate 23 has emission surfaces 23a and 23b. A scattering dot pattern, a prism shape portion, or the like is formed on both or one of the emission surface 23a and the emission surface 23b. The scattering dot pattern, the prism-shaped portion, and the like are for adjusting the intensity distribution of light in the plane and the light emission direction while emitting light.

  An optical sheet 22 is disposed on the light guide plate 23 in order to adjust the intensity distribution of the emitted light and the light emission angle. The optical sheet 22 is a lens sheet for condensing light, a diffusion sheet for homogenizing light, a viewing angle adjusting sheet for adjusting luminance in the viewing angle direction, and the like. The required number of optical sheets 22 is arranged according to the purpose.

  The front housing 21 has an opening 3H. The opening 3 </ b> H serves as a path for light emitted from the emission surface 23 a of the light guide plate 23. The display panel 10 is mounted and positioned on the periphery of the upper surface of the front housing 21. Thereby, the display panel 10 is held by the front housing 21. The material constituting the front housing 21 is a metal such as aluminum, stainless steel or iron, or a resin material such as PC (polycarbonate) or ABS (acrylonitrile butadiene styrene).

  A light source 25 is positioned on the rear housing 26. That is, the back housing 26 holds the light source 25. In order to conduct the heat emitted from the light source 25, it is desirable to use a metal having high thermal conductivity. Therefore, the back housing 26 is made of aluminum or an aluminum alloy having particularly high thermal conductivity. With this configuration, heat from the light source 25 can be efficiently diffused, and the temperature of the light source 25 can be lowered.

  The front casing 21 and the rear casing 26 are generally fixed to each other by a hook structure with a claw, screwing or the like. Thereby, another backlight member, the display panel 10, the circuit board 5, etc. are held. Note that the structure is not limited to the above structure, and the front housing 21 and the back housing 26 may be integrated.

(Casing)
The housing 3 is a frame-like member that holds the display panel 10, the backlight 20, the touch panel 4, and the like. The housing 3 is composed of a thin metal plate, a resin molded product, or the like. The housing 3 is fixed to the backlight 20 by a claw-like fixing structure, screwing, or the like. The housing 3 may be formed integrally or may be configured by combining a plurality of members. Moreover, you may provide the attachment part (screw, attachment hole, etc.) to a final product in the side surface of the housing | casing 3, a front surface, a back surface, or a peripheral part.

(Touch panel)
The touch panel 4 includes a transparent substrate and a circuit using a transparent electrode formed on the transparent substrate. The touch panel 4 converts information on position coordinates input from the outside (user) into an electrical signal by the above circuit. The touch panel 4 transmits the electrical signal to the control circuit of the final product via the output wiring portion 4c connected to the end of the touch panel 4.

  For the output wiring portion 4c, FPC (Flexible Printed Circuits) in which wiring is formed on a base material on a film is used because of the freedom of connection due to thinness and flexibility. The output wiring portion 4c is not limited to the FPC, and may be made of different materials and different structures as long as they have equivalent functions and characteristics.

(Transparent protective plate)
The transparent protective plate 6 is a plate for preventing damage to the surface 4a of the touch panel 4 due to pressure, contact, etc., deformation, wear, dirt, etc. of the touch panel 4. The transparent protective plate 6 is provided on the surface 4 a side of the touch panel 4. The transparent protective plate 6 is joined to the touch panel 4 by a cured resin J10a obtained by curing the ultraviolet curable resin J10.

  The transparent protective plate 6 is made of a transparent material such as glass or plastic. A frame-like member can be added to the peripheral portion of the front surface or the back surface of the transparent protective plate 6 for the purpose of light shielding or design.

  In the present embodiment, the structure in which the touch panel 4 and the transparent protective plate 6 are joined to the display panel 10 by the cured resin J10a obtained by curing the ultraviolet curable resin J10 is described, but the present invention is not limited to this structure.

  For example, the display panel 10 may have a structure in which only one of the touch panel 4 and the transparent protective plate 6 is bonded. For example, as described above, in the display device 100 having the modified configuration A that does not include the touch panel 4, the transparent protective plate 6 is bonded to the surface of the display panel 10 on which the image is displayed by the cured resin J10a.

  Moreover, the member joined to the display panel 10 is good also as a structure where only the peripheral part of the said member was fixed to the display panel 10 with the double-sided adhesive tape.

(Circuit board)
The circuit board 5 controls the display unit and the light source unit by electrical input / output. The circuit board 5 is usually configured by forming a copper pattern on glass epoxy or the like and mounting electronic components on the surface of the glass epoxy by soldering. The circuit board 5 is disposed (fixed) mainly on the back surface side (the side on which light is not emitted) of the backlight 20.

  The circuit board 5 may be configured by mounting electronic components on FPC (Flexible Printed Circuits) in which wiring is formed on a base material on a film connected to the display panel 10.

  Further, a protective cover (not shown) may be attached to the circuit board 5 in order to protect the circuit board 5 from external pressure and static electricity. The protective cover is made of a metal such as aluminum, stainless steel, or a galvanized steel plate, or a thin film-like resin such as PET.

  When a metal protective cover is used, a resin sheet such as PET is affixed to the circuit board 5 in order to avoid electrical contact with the circuit board 5 and electronic components on the circuit board 5. Thereby, insulation measures can be taken.

  Next, a method for manufacturing the display device 100 according to the present embodiment and effects obtained thereby will be described. Hereinafter, the manufacturing method according to the present embodiment of display device 100 is also referred to as manufacturing method A. In the manufacturing method A, the joining process A which joins the display panel 10 and the transparent member 50 is performed. The transparent member 50 is the touch panel 4 or the transparent protective plate 6 as described above.

  The bonding process A includes the resin supply process N and the ultraviolet irradiation process A described above. That is, the manufacturing method A includes the ultraviolet irradiation step A.

  In the ultraviolet irradiation step A, an ultraviolet irradiation device 500 is used. That is, the ultraviolet irradiation device 500 used in the ultraviolet irradiation step A included in the manufacturing method A for manufacturing the display device 100 is a manufacturing device for manufacturing the display device 100. In other words, the ultraviolet irradiation device 500 is a display device manufacturing apparatus.

  Hereinafter, the display device 100 in which the transparent member 50 is not bonded to the display panel 10 and does not include the transparent member 50 is also referred to as a display device N1. By performing the above-described resin supply process N on the display device N1, the ultraviolet curable resin J10 is filled between the display panel 10 and the transparent member 50 of the display device N1.

  As described above, the ultraviolet curable resin J10 is an uncured ultraviolet curable resin. The ultraviolet curable resin J10 is cured by being irradiated with ultraviolet rays. Specifically, as described above, the ultraviolet curable resin J10 is a resin that cures a portion of the ultraviolet curable resin J10 that has been irradiated with ultraviolet rays when the ultraviolet curable resin J10 is irradiated with ultraviolet rays.

  The transparent member 50 is joined to the display apparatus N1 by performing the resin supply process N with respect to the display apparatus N1. Hereinafter, the display device N1 to which the transparent member 50 is bonded by the ultraviolet curable resin J10 is also referred to as a display device 100N.

  When the ultraviolet curable resin J10 of the display device 100N is cured and the ultraviolet curable resin J10 becomes the cured resin J10a, the display device 100N becomes the display device 100. That is, the display device 100N is a device that is being manufactured.

  As described above, the transparent member 50 is a member that transmits ultraviolet rays. The transparent member 50 has a display surface 50a. The image light constituting the image displayed on the display panel 10 of the display device 100 is transmitted through the cured resin J10a and the transparent member 50, whereby the display surface 50a of the transparent member 50 displays an image. That is, the display surface 50a is a surface for displaying an image.

  First, the ultraviolet irradiation device 500 will be described. FIG. 3 is a diagram showing an ultraviolet irradiation device 500 used in the ultraviolet irradiation step A according to Embodiment 1 of the present invention. The ultraviolet irradiation device 500 is a device that irradiates ultraviolet rays.

  Hereinafter, the region irradiated with ultraviolet rays is also referred to as an irradiation region R20. Although the ultraviolet irradiation device 500 will be described in detail later, it is possible to arbitrarily set the intensity and irradiation time of the ultraviolet rays to be irradiated. Further, the ultraviolet irradiation device 500 can control the size of the irradiation region R20. That is, the ultraviolet irradiation device 500 can irradiate only a desired region of the ultraviolet curable resin with ultraviolet rays. Furthermore, the ultraviolet irradiation device 500 can continuously change the position and size of the irradiation region R20.

  The ultraviolet irradiation device 500 includes an ultraviolet irradiation unit 510, a shutter mechanism 511, a stage 530, an ultraviolet control unit 520, and a stage control unit 540.

  The ultraviolet irradiation unit 510 irradiates ultraviolet rays under the control of the ultraviolet control unit 520.

  The shutter mechanism 511 adjusts the position and size of the irradiation region R20. The shutter 511 is configured to be able to control the amount of passing ultraviolet rays. The shutter mechanism 511 is configured by combining a plurality of wing-like thin plate members, for example, in order to realize a mechanical stop in the ultraviolet passage region. Note that the shutter mechanism 511 is not limited to the above configuration, and may be configured by an optical filter that can variably control the transmittance at each position by an electric signal, for example.

  The stage 530 is a moving device for moving an object. The stage 530 has a table 531. The base 531 is configured to be movable. A display device 100 </ b> N in the middle of manufacture is placed on the stand 531.

  The ultraviolet control unit 520 controls the irradiation intensity of the ultraviolet rays that the ultraviolet irradiation unit 510 irradiates. Further, the ultraviolet light control unit 520 controls the irradiation range (the size of the irradiation region R20) irradiated by the ultraviolet irradiation unit 510 by controlling the open / close state of the shutter mechanism 511.

  The stage controller 540 controls the position and moving speed of the stage 531 of the stage 530. Note that the ultraviolet control unit 520 and the stage control unit 540 may be configured integrally. Further, the stage 531 of the stage 530 may be configured to be manually movable.

  In a state where the display device 100N is fixed so that the position of the display device 100N mounted on the table 531 is an appropriate position with respect to the ultraviolet irradiation unit 510, the ultraviolet light control unit 520 sets the irradiation intensity set in advance. The ultraviolet irradiation unit 510 is controlled according to the irradiation region. In other words, the ultraviolet ray control unit 520 controls the ultraviolet ray irradiation unit 510 so that the ultraviolet ray irradiation unit 510 irradiates the display device 100N with ultraviolet rays according to a preset irradiation intensity and irradiation region. Thereby, hardening of ultraviolet curable resin J10 advances and the display panel 10 and the transparent member 50 are joined firmly.

  Next, the ultraviolet irradiation process A will be described. FIG. 4 is a diagram for explaining the ultraviolet irradiation step A according to Embodiment 1 of the present invention. FIG. 4 shows a state from the start to the end of ultraviolet irradiation.

  Here, as shown in FIG. 3, it is assumed that the display device 100 </ b> N being manufactured is placed on the stage 531 of the stage 530. Hereinafter, the state in which the display panel 10 of the display device 100N and the transparent member 50 are bonded by the ultraviolet curable resin J10 is also referred to as a pre-cured bonded state.

  In the ultraviolet irradiation process A, the position of the irradiation region R20 is set at the center of the display surface 50a until the ultraviolet irradiation unit 510 is irradiated with ultraviolet rays in the planar view of the ultraviolet curable resin J10 in the bonded state before curing. Then, ultraviolet rays are irradiated while continuously moving from the edge to the periphery of the display surface 50a. The entire region in the plan view of the ultraviolet curable resin J10 is the entire region in the XY plane of the ultraviolet curable resin J10.

  That is, in the ultraviolet irradiation process A, the position of the irradiation region R20 is set on the display surface 50a until the ultraviolet irradiation unit 510 is irradiated with ultraviolet rays in the planar view of the ultraviolet curable resin J10 in the bonded state before curing. Ultraviolet rays are irradiated while continuously changing from a part of the area to another part of the display surface 50a.

  In the ultraviolet irradiation process A, the ultraviolet irradiation unit 510 irradiates ultraviolet rays so that the position of the irradiation region R20 gradually moves. In the ultraviolet irradiation process A, the ultraviolet irradiation unit 510 irradiates ultraviolet rays so that the moving speed of the position of the irradiation region R20 becomes a constant speed.

  Moreover, the shape of the XY plane of the irradiation region R20 when the position of the irradiation region R20 is moved in the ultraviolet irradiation step A is, for example, an annular shape. In the ultraviolet irradiation step A, the ultraviolet irradiation unit 510 irradiates ultraviolet rays so that the diameter of the annular irradiation region R20 gradually increases. In the ultraviolet irradiation step A, the position of the irradiation region R20 gradually moves as the diameter of the annular irradiation region R20 gradually increases.

  Below, the area | region where the ultraviolet-ray is irradiated among all the area | regions by planar view of the ultraviolet curable resin J10 is also called irradiation resin area | region. In the following, the ultraviolet curable resin J10 in the irradiation resin region in plan view is also referred to as irradiation region resin N. The irradiation region resin N is a part of the entire ultraviolet curable resin J10.

  Hereinafter, the uncured ultraviolet curable resin J10 is also referred to as an uncured resin. The uncured resin has fluidity. Hereinafter, the display panel 10 and the transparent member 50 are also referred to as members to be joined. Note that, as described above, in the entire ultraviolet curable resin J10, a region that has been cured to the maximum when irradiated with ultraviolet rays is also referred to as a cured region R5.

  FIG. 4A shows the position of the irradiation region R20 at the start of the ultraviolet irradiation step A. FIG. As shown in FIG. 4A, in the ultraviolet irradiation step A, the irradiation of ultraviolet rays is started from a limited range, that is, the central portion of the display surface 50a. That is, ultraviolet rays are applied to the central portion of the ultraviolet curable resin J10.

  Thereby, the irradiation region resin N in the irradiation resin region is cured by the ultraviolet rays transmitted through the transparent member 50. If the entire upper surface of the ultraviolet curable resin J10 is irradiated with ultraviolet rays as in the comparative example described above, the volume of the irradiated region resin N decreases due to curing and shrinkage.

  On the other hand, in the present embodiment, there is always an uncured resin having fluidity in the periphery of the irradiation region resin N where curing proceeds. Therefore, the irradiation region resin N is cured while being supplemented with the uncured resin present in the periphery of the irradiation region resin N. Therefore, it is possible to avoid the occurrence of stress between the display panel 10 and the transparent member 50 (between the bonded members). In addition, the area | region where the irradiation area | region resin N hardened | cured until hardness became the maximum exists is hardening area | region R5.

  FIG. 4B shows a state near the middle of the period from the start of the ultraviolet irradiation step A to the end of the ultraviolet irradiation step A. That is, FIG.4 (b) shows the state which hardening area | region R5 in ultraviolet curable resin J10 expanded from the state of Fig.4 (a). Also in the state of FIG. 4B, the irradiation region resin N is cured while being supplemented with the uncured resin present in the peripheral portion of the irradiation region resin N.

  FIG. 4C is a diagram illustrating a state in which the ultraviolet irradiation unit 510 irradiates the peripheral portion of the display surface 50a with ultraviolet rays. In the state of FIG.4 (c), the peripheral part of the display surface 50a is irradiation region R20. When the peripheral portion of the ultraviolet curable resin J10 corresponding to the position of the peripheral portion of the display surface 50a in the X-axis direction is completely cured, the ultraviolet irradiation step A is completed. At the end of the ultraviolet irradiation step A, the ultraviolet curable resin J10 is the cured resin J10a. Thereby, the display device 100 is manufactured. That is, the manufacturing method A ends.

  As described above, according to the present embodiment, in the state where the display panel 10 and the transparent member 50 are joined by the ultraviolet curable resin J10, the entire region of the ultraviolet curable resin J10 in the plan view is irradiated with ultraviolet rays. Until the irradiation is performed, the position of the irradiation region R20 irradiated with ultraviolet rays continuously changes from the region that is a part of the display surface 50a of the transparent member 50 to the region that is another part of the display surface 50a. Irradiated.

  That is, in the present invention, as in the prior art, the entire surface of the ultraviolet curable resin J10 is not irradiated with ultraviolet rays, and the ultraviolet rays are irradiated to a part of the ultraviolet curable resin J10 while the position of the irradiation region R20 is changed. Therefore, the portion cured by the ultraviolet light that passes through the transparent member 50 continuously spreads from a partial region of the ultraviolet curable resin J10 to the entire region of the ultraviolet curable resin J10. That is, before the entire region of the ultraviolet curable resin J10 is cured, an uncured ultraviolet curable resin exists around the region where curing proceeds by ultraviolet rays in the entire region of the ultraviolet curable resin J10.

  Thereby, the uncured ultraviolet curable resin is always supplemented in the region where the curing proceeds. As a result, the generation of stress between the display panel 10 and the transparent member 50 can be sufficiently suppressed until the entire region of the ultraviolet curable resin J10 is cured. Therefore, according to this Embodiment, generation | occurrence | production of the malfunction resulting from the ultraviolet curable resin used for joining of a display panel can be suppressed.

  Further, according to the present embodiment, in the ultraviolet irradiation step A, the irradiation region R20 is gradually moved from a part of the display surface to the peripheral part of the display surface adjacent to the part of the display surface. As a result, the area of the cured region R5 is continuously expanded in a state where the uncured resin exists around the irradiation region R20. At this time, an uncured resin having fluidity is supplied from the periphery of the irradiation region resin N where curing proceeds, against shrinkage due to curing.

  Thereby, the stress applied to the display panel 10 due to the shrinkage of the resin is relieved. As a result, it is possible to suppress the occurrence of display unevenness of the video displayed on the display panel 10 of the display device 100.

  Further, according to the present embodiment, in the display device 100N bonded to the transparent member 50 using the ultraviolet curable resin J10, the shrinkage of the ultraviolet curable resin J10 upon curing and the warping of the transparent member 50 cause the resin Generation of stress at the joint can be suppressed. Accordingly, it is possible to obtain the display device 100 having high image display quality without unevenness.

  Moreover, according to this Embodiment, as above-mentioned, irradiation area | region R20 is moved continuously from the center part of the display surface 50a to the peripheral part of the display surface 50a. Around the irradiation region resin N where the curing proceeds, there is always an uncured resin having fluidity.

  Therefore, the volume change due to the curing and shrinkage of the irradiation region resin N is supplemented by the uncured resin. As a result, deformation due to stress on the display panel 10 and the transparent member 50 can be significantly suppressed. Therefore, it is possible to obtain the display device 100 having good display quality without display unevenness, peeling at the joint surface of the resin, and the like.

  In addition, in order to avoid the malfunction by the volume reduction | decrease of the said ultraviolet curable resin at the time of using an ultraviolet curable resin like the above-mentioned related art A, a gel-like transparent resin sheet uses a display panel and a protective plate. There is also a technique for joining.

  However, this method cannot absorb a level difference (a level difference between the display surface and the casing in the peripheral portion of the screen), a level difference due to dust, foreign matter, or the like on the bonding surface. As a result, there is a problem that bubbles are generated in the vicinity of the steps and the yield rate is reduced.

  On the other hand, since the present embodiment is configured as described above, the above problem can be solved.

<Embodiment 2>
In the first embodiment, the method of irradiating ultraviolet rays while continuously moving the position of the irradiation region R20 from the central portion of the display surface 50a to the peripheral portion of the display surface 50a has been described. In the present embodiment, a method for continuously moving the position of the irradiation region R20 from one end of the display surface 50a to the other end of the display surface 50a will be described.

  Hereinafter, the manufacturing method according to the present embodiment of display device 100 is also referred to as manufacturing method B. In the manufacturing method B, the joining process B which joins the display panel 10 and the transparent member 50 is performed. The transparent member 50 is the touch panel 4 or the transparent protective plate 6 as described above.

  The bonding process B includes the resin supply process N and the ultraviolet irradiation process B described above. That is, the manufacturing method B includes the ultraviolet irradiation step B.

  In the ultraviolet irradiation process B, the ultraviolet irradiation apparatus 500 described in the first embodiment is used. That is, the ultraviolet irradiation device 500 used in the ultraviolet irradiation step B included in the manufacturing method B for manufacturing the display device 100 is a manufacturing device for manufacturing the display device 100. In other words, the ultraviolet irradiation device 500 is a display device manufacturing apparatus.

  By performing the above-described resin supply process N on the display device N1, the ultraviolet curable resin J10 is filled between the display panel 10 and the transparent member 50 of the display device N1. Thereby, the display device N1 becomes the display device 100N.

  Next, the ultraviolet irradiation process B will be described. FIG. 5 is a diagram for explaining the ultraviolet irradiation step B according to Embodiment 2 of the present invention. FIG. 5 shows an irradiation region R20 in each stage of the ultraviolet irradiation process B. Further, in FIG. 5, an ultraviolet irradiation unit 510 of the ultraviolet irradiation device 500 is shown for explanation.

  The ultraviolet irradiation device 500 can arbitrarily set the intensity and irradiation time of ultraviolet rays to be irradiated. Further, the ultraviolet irradiation unit 510 of the ultraviolet irradiation device 500 is movable at a desired speed with respect to the display device 100N that is in the process of being mounted on a table 531 (not shown).

  Here, as shown in FIG. 3, it is assumed that the display device 100 </ b> N being manufactured is placed on the stage 531 of the stage 530. As described above, the state in which the display panel 10 of the display device 100N and the transparent member 50 are bonded by the ultraviolet curable resin J10 is also referred to as a pre-curing bonded state.

  As shown in FIG. 5A to FIG. 5C, in the ultraviolet irradiation process B, the ultraviolet irradiation unit 510 moves the irradiation region R20 from one end of the display surface 50a to the other end of the display surface 50a. Irradiate ultraviolet rays so as to move continuously to the part. That is, in the ultraviolet irradiation process B, the position of the irradiation region R20 is set on the display surface 50a until the ultraviolet irradiation unit 510 irradiates the entire region in the planar view of the ultraviolet curable resin J10 in the bonded state before curing. Ultraviolet rays are irradiated while continuously changing from a part of the area to another part of the display surface 50a.

  Note that the size of the irradiation region R20 in the Y-axis direction when the irradiation region R20 is moving in the ultraviolet irradiation process B is, for example, the same as the size of the display surface 50a in the Y-axis direction.

  In the ultraviolet irradiation process B, the ultraviolet irradiation unit 510 irradiates ultraviolet rays so that the position of the irradiation region R20 gradually moves. Specifically, the ultraviolet irradiation unit 510 gradually (continuously) from one end of the display surface 50a to the other end of the display surface 50a so that the position of the irradiation region R20 gradually moves. Move in the direction. In the ultraviolet irradiation process B, the ultraviolet irradiation unit 510 moves at a constant speed. Thereby, the ultraviolet irradiation unit 510 irradiates ultraviolet rays so that the moving speed of the position of the irradiation region R20 becomes a constant speed.

  Note that FIG. 5 shows a configuration in which the ultraviolet irradiation unit 510 moves in the X direction, but the ultraviolet irradiation unit 510 may move in the −X direction. As shown in FIG. 5C, when the entire ultraviolet curable resin J10 is completely cured, the ultraviolet irradiation process B ends. At the end of the ultraviolet irradiation step B, the ultraviolet curable resin J10 is the cured resin J10a. Thereby, the display device 100 is manufactured. That is, the manufacturing method B ends. In the following, a portion of the entire ultraviolet curable resin J10 in a plan view that is not irradiated with ultraviolet rays is also referred to as an unirradiated portion.

  As described above, according to the ultraviolet irradiation process B of the present embodiment, the irradiation of ultraviolet rays is started from one end of the display surface 50a. By starting the irradiation of ultraviolet rays from the one end portion, there is always an uncured resin having fluidity at the boundary portion between the irradiation region resin N where the curing proceeds and the ultraviolet ray non-irradiated portion. As in the comparative example, if the entire upper surface of the ultraviolet curable resin J10 is irradiated with ultraviolet rays, the volume of the irradiated region resin N decreases due to curing and contraction.

  On the other hand, in the present embodiment, until the entire ultraviolet curable resin J10 is completely cured, an uncured resin having fluidity always exists in the peripheral portion of the irradiation region resin N where the curing proceeds. Therefore, the irradiation region resin N is cured while being supplemented with the uncured resin present in the periphery of the irradiation region resin N. Therefore, it is possible to avoid the occurrence of stress between the display panel 10 and the transparent member 50 (between the bonded members).

  Further, in the present embodiment, as shown in FIG. 5, after starting the irradiation of ultraviolet rays from one end of the display surface 50a, the ultraviolet irradiation unit 510 that irradiates the ultraviolet rays is continuously moved. Thereby, the entire ultraviolet curable resin J10 is finally completely cured while expanding the curing region R5.

  Even when the ultraviolet irradiation unit 510 is moved, an uncured resin having fluidity is always present in the periphery of the irradiation region resin N where curing proceeds, while continuously expanding the curing region R5. Exists. Therefore, the irradiation region resin N is cured while being supplemented with the uncured resin present in the periphery of the irradiation region resin N. That is, the irradiation region resin N that progresses in curing is suppressed in volume change by the uncured resin.

  Thereby, the stress applied to the display panel 10 and the transparent member 50 due to the shrinkage of the resin can be sufficiently reduced. As a result, deformation of the display panel 10 and the transparent member 50 due to stress can be significantly suppressed. Therefore, it is possible to obtain the display device 100 having a good video display quality without display unevenness and peeling at the joint surface of the resin.

  In addition, in the ultraviolet irradiation process B of this Embodiment, although the ultraviolet irradiation part 510 was set as the structure moved, it is not limited to this. Other configurations may be employed as long as the position of the irradiation region R20 continuously moves from one end of the display surface 50a to the other end of the display surface 50a. The other configuration is, for example, a configuration that moves the display device 100N (hereinafter referred to as a modified configuration B).

  Next, the ultraviolet irradiation process B of the modified configuration B will be described. Below, the ultraviolet irradiation process B of the deformation | transformation structure B is also called ultraviolet irradiation process B1. Here, as shown in FIG. 3, it is assumed that the display device 100 </ b> N being manufactured is placed on the stage 531 of the stage 530. The stage 530 moves the table 531 according to control by the stage control unit 540. That is, the stage 530 is a moving device having a function of moving the display panel 10 and the transparent member 50 of the display device 100N placed on the stand 531.

  In the ultraviolet irradiation process B1, the stage 530 continuously moves the irradiation region R20 from one end of the display surface 50a to the other end of the display surface 50a while the position of the ultraviolet irradiation unit 510 is fixed. As described above, the display panel 10 and the transparent member 50 are moved.

  For example, in the state where the position of the ultraviolet irradiation unit 510 is shown in FIG. 5A, in the stage 530, the irradiation region R20 continuously moves from one end of the display surface 50a to the other end of the display surface 50a. As described above, the display panel 10 and the transparent member 50 of the display device 100N are moved in the −X direction. Note that the size of the irradiation region R20 in the Y-axis direction when the display panel 10 and the transparent member 50 are moving in the ultraviolet irradiation step B1 is, for example, the same as the size of the display surface 50a in the Y-axis direction.

  That is, in the ultraviolet irradiation step B1, the position of the irradiation region R20 is set on the display surface 50a until the ultraviolet irradiation unit 510 irradiates the entire region in the plan view of the ultraviolet curable resin J10 in the bonded state before curing. Ultraviolet rays are irradiated while continuously changing from a part of the area to another part of the display surface 50a.

  Also in the above ultraviolet irradiation process B1, the same effect as the above-mentioned ultraviolet irradiation process B is acquired.

  The configuration in which the position of the irradiation region R20 continuously moves from one end of the display surface 50a to the other end of the display surface 50a is not limited to the modified configuration B, and the ultraviolet irradiation unit 510 and the display device It is good also as a structure which moves both 100N (the display panel 10 and the transparent member 50).

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

  3 housing, 4 touch panel, 6 transparent protective plate, 10 display panel, 20 backlight, 50 transparent member, 100, 100N, N1 display device, 500 ultraviolet irradiation device, 510 ultraviolet irradiation unit, 530 stage, J10 ultraviolet curable resin, J10a cured resin, R5 cured region, R20 irradiated region.

Claims (2)

A display panel comprising: a display panel that displays an image; and a transparent member that is provided on a surface of the display panel that displays the image and transmits ultraviolet light.
In a state in which the display panel and the transparent member are bonded by an ultraviolet curable resin that is cured by being irradiated with the ultraviolet rays, one ultraviolet irradiation unit is disposed on the entire area of the ultraviolet curable resin in a plan view. Until the ultraviolet ray is irradiated, the position of the irradiation region irradiated with the ultraviolet ray is continuously moved from the central part of the display surface for displaying the image of the transparent member to the peripheral part of the display surface. A method for manufacturing a display device, comprising an ultraviolet irradiation step of irradiating the ultraviolet rays. A manufacturing apparatus for manufacturing a display device that includes a display panel that displays an image, and a transparent member that is provided on a surface of the display panel that displays the image and transmits ultraviolet light.
Including one ultraviolet irradiation unit for irradiating the ultraviolet rays;
The one ultraviolet irradiating unit covers the entire area of the ultraviolet curable resin in a plan view in a state where the display panel and the transparent member are bonded by an ultraviolet curable resin that is cured by being irradiated with the ultraviolet light. Until the ultraviolet ray is irradiated, the position of the irradiation region irradiated with the ultraviolet ray is continuously moved from the central portion of the display surface for displaying the image to the peripheral portion of the display surface of the transparent member. A manufacturing device that irradiates the ultraviolet light.

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