JP2015031834A - Liquid crystal display device and method for manufacturing liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a narrow frame structure that has an antistatic function, and has both of remediation in display unevenness and securing of long term adhesion reliability between a panel and a structure.SOLUTION: A liquid crystal display device includes: a panel that is provided on a front surface side; and a light source part that is provided on a rear surface side. The panel is configured by sequentially laminating a front surface polarization plate (3a), a conductive sheet (2), a front surface substrate (1a), a rear surface substrate (1b) and a rear surface polarization plate (3b). In a panel end part, a rear surface end part of the front surface polarization plate, a front surface end part of the rear surface substrate and a rear surface end part thereof are laminated so as to be exposed. The light source part is configured to have a light guide plate provided on a rear surface cover, and in the panel end part, the liquid crystal display device further includes a metal frame (21) that is connected across the rear surface end part of the rear surface substrate, the conductive sheet and a side surface of the front surface substrate, and the front surface end part of the rear surface substrate and the rear surface end part thereof and a side surface of a rear surface cover, that is composed of an almost F-shaped metal material having conductivity, and is connected to the ground.

Description

  The present invention relates to a liquid crystal display device suitable for narrowing a frame for expanding an image displayable region and a method for manufacturing the liquid crystal display device, and in particular, to improve display performance (whitening phenomenon and display unevenness), and to a panel and a structure. It is related with the structure which realizes ensuring long-term adhesion reliability.

  FIG. 2 is a diagram showing a cross-sectional structure of a conventional liquid crystal display device. 2 includes a front substrate 101a, a rear substrate 101b, a conductive sheet 102, a front polarizing plate 103a, a rear polarizing plate 103b, a side black seal 104, a light guide plate 111, a back cover 112, a metal frame 121, And an adhesive 122.

  Here, the front side (panel side) of the liquid crystal display device is configured by laminating a rear polarizing plate 103b, a rear substrate 101b, a front substrate 101a, a conductive sheet 102, and a front polarizing plate 103a. Further, a non-conductive side black seal 104 is provided on the side surface portion of the front substrate 101a so as to connect the front polarizing plate 103a, the conductive sheet 102, the front substrate 101a, and the rear substrate 101b to each other. It has been.

  On the other hand, the back side (light source side) of the liquid crystal display device is configured to include the light guide plate 111 on the back cover 112, and an L-shaped metal frame 121 covers the frame portion on the light source side. Is provided. Furthermore, the back side of the back substrate 101 b on the front side and the metal frame 121 are bonded via an adhesive 122.

  In the configuration of FIG. 2, the side black seal 104 provided on the side surface of the front substrate 101a does not have conductivity. Therefore, since the conductive sheet 102 provided on the panel surface side cannot be reliably grounded, it cannot be prevented from being charged and a whitening phenomenon occurs.

  Therefore, there is a conventional liquid crystal display device that prevents charging. FIG. 3 is a diagram showing a cross-sectional structure of another conventional liquid crystal display device. The liquid crystal display device shown in FIG. 3 includes a substrate 201, a conductive sheet 202, a front polarizing plate 203a, a back polarizing plate 203b, a light guide plate 211, a back cover 212, and a metal frame 221.

  The front side (panel side) of the liquid crystal display device is configured by laminating a rear polarizing plate 203b, a substrate 201, a conductive sheet 202, and a front polarizing plate 203a. On the other hand, the back side (light source side) of the liquid crystal display device includes a light guide plate 211 on a back cover 212. Further, a metal frame 221 is provided to electrically connect the conductive sheet 202 and the back cover 212 so as to be grounded, thereby preventing charging. It is fixed so as to overlap the surface edge of the polarizing plate 203a (see, for example, Patent Document 1).

  In particular, in the IPS mode, in order to prevent charging, it is common to use ITO and a transparent conductive film as the conductive sheet 202 provided on the panel surface as shown in FIG.

JP 2006-161004 A

However, the prior art has the following problems.
In the prior art shown in FIG. 3, in order to connect the conductive sheet 202 to the ground, the end portion of the metal frame 221 is bent to the surface portion of the liquid crystal display device, and the conductive adhesive 204 is interposed therebetween. It is necessary to connect the metal frame 221 and the conductive sheet 202.

  In addition, in order to realize a narrow frame for widening an image displayable area, long-term adhesion reliability can be secured by reducing the amount of bending of the end of the metal frame 221 to the surface portion of the liquid crystal display device more than necessary. In addition, since the conductive sheet 202 cannot be reliably grounded for a long period of time, charging cannot be prevented and a whitening phenomenon occurs. Therefore, it is desired to realize a narrow frame structure having a new antistatic function.

  Also in the prior art shown in FIG. 2, as described above, because the side black seal 104 does not have conductivity, the conductive sheet 102 cannot be reliably grounded. There is a similar problem that it is impossible to prevent charging and a whitening phenomenon occurs.

  Furthermore, the adhesive 122 is used in the prior art shown in FIG. 2 as a structure for connecting the panel and the structure. However, when a hard adhesive or a high-strength adhesive is used as the adhesive 122, the distortion of the panel cannot be relieved sufficiently. As a result, stress is directly applied to the panel itself, and the alignment of the liquid crystal is shifted and unevenness occurs.

  In addition, when a soft adhesive or a soft adhesive is used as the adhesive 122, the adhesive area is limited in order to realize a narrow frame, so that sufficient adhesive force can be maintained to maintain the panel load. There is a problem that there is no.

  Further, when a double-sided tape is used as the adhesive 122, a sufficient adhesion area can be secured, but it cannot be applied within a certain width due to a problem of cutting processing. In addition, since the back substrate 101b and the metal frame 121 are not uniformly adhered, there is a problem that the adhesive force is not uniformly applied.

  On the other hand, regarding the configuration for connecting the panel and the structure, in the prior art shown in FIG. 3, only the metal frame 221 is used, and improvement in connection strength and long-term adhesion reliability are desired.

  The present invention has been made to solve the above-described problems, and has a narrow frame that has an antistatic function, improves display unevenness, and ensures long-term adhesion reliability between the panel and the structure. It is an object of the present invention to obtain a liquid crystal display element and a method of manufacturing a liquid crystal display device that can realize a structured structure.

  The liquid crystal display device according to the present invention is a liquid crystal display device comprising a panel provided on the front side and a light source unit provided on the back side, the panel comprising a front polarizing plate, a conductive sheet, and a front substrate. The back substrate and the back polarizing plate are laminated in order, and at the end of the panel, the back end of the front polarizing plate and the front end and back end of the back substrate are exposed. The light source unit includes a light guide plate on the back cover, and at the panel end, the back end of the front polarizing plate, the side surface of the conductive sheet and the front substrate, the front end of the back substrate, and A metal frame having a substantially F shape and made of a conductive metal material and connected to the ground so as to be connected across the back end and the side surface of the back cover constituting the light source unit. More to prepare A.

  In addition, a method for manufacturing a liquid crystal display device according to the present invention is a method for manufacturing a liquid crystal display device including a panel provided on the front side and a light source unit provided on the back side. Laminating sheet, front substrate, rear substrate, rear polarizing plate in order, and so that the back end of front polarizing plate and the front end and back end of back substrate are exposed at the panel edge Manufacturing the panel in step, manufacturing the light source by providing a light guide plate on the back cover, and the back end of the front polarizing plate, the conductive sheet and the front substrate at the panel end. Side surfaces, the front and back end portions of the back substrate, and the side surface of the back cover that constitutes the light source unit, using a substantially F-shaped frame made of a conductive metal material. Connect to ground Those having a step.

  According to the present invention, a metal frame having a substantially F shape is used for connection between a panel and a structure of a liquid crystal display device, thereby providing an antistatic function and improving display unevenness, and the panel and structure. And a method for manufacturing a liquid crystal display element and a liquid crystal display device that can realize a narrow frame structure having long-term adhesion reliability.

It is the figure which showed the cross-section of the liquid crystal display device in Embodiment 1 of this invention. It is the figure which showed the cross-section of the conventional liquid crystal display device. It is the figure which showed the cross-section of another conventional liquid crystal display device.

  Hereinafter, preferred embodiments of a liquid crystal display element and a method for producing a liquid crystal display device of the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a cross-sectional structure of a liquid crystal display device according to Embodiment 1 of the present invention, and shows a conductive polarizing plate type liquid crystal display device. More specifically, FIG. 1A shows a cross-sectional view, and FIG. 1B shows a three-dimensional structure diagram. Such a liquid crystal display device according to the first embodiment includes a front substrate 1a, a rear substrate 1b, a conductive sheet 2, a front polarizing plate 3a, a rear polarizing plate 3b, a light guide plate 11, a rear cover 12, a metal frame 21, and A conductive adhesive 22 (or a conductive double-sided tape) is provided.

  Thus, the front side (panel side) of the liquid crystal display device including the front substrate 1a and the back substrate 1b has the conductive sheet 2 and the front polarizing plate 3a on the front side, and the back polarization on the back side. It has a plate 3b. Here, the conductive sheet 2 can be composed of any one of a conductive polarizing plate, a transparent conductive film, and an ITO film.

  And in the side part of the front substrate 1a, the metal frame 21 having a substantially F-shape is formed of a conductive adhesive so as to cover all of the front substrate 1a, the back substrate 1b, the conductive sheet 2, and the front polarizing plate 3a. It is connected via the agent 22. That is, the panel side which is the front side of the liquid crystal display device is configured by sequentially laminating the front polarizing plate 3a, the conductive sheet 2, the front substrate 1a, the back substrate 1b, and the back polarizing plate 3b, and at the end of the panel. The back surface of the front polarizing plate 3a and the back surface of the back substrate 1b are laminated so that the front surface and the back surface are exposed, and the exposed portions, the side surface of the front substrate 1a, and the side surface of the conductive sheet 2 have a substantially F shape. The metal frames 21 are connected to each other.

  On the other hand, the back side (light source side) of the liquid crystal display device is configured to include the light guide plate 11 on the back cover 12, and the above-described metal frame 21 having the substantially F shape forms the frame portion on the light source side. It is provided to cover. As shown in FIG. 1B, the metal frame 21 having a substantially F shape is connected to an IC portion formed by COF (Chip On Film) provided at an end portion of the back substrate 1b and pulled out to the outside. An opening 21a is provided to allow the wiring to pass through.

Further, the rear substrate 1b on the panel side and the metal frame 21 having a substantially F shape are bonded via the adhesive 22 described above. That is, according to the configuration of FIG. 1 according to the first embodiment, the following features are realized by using the metal frame 21 having a substantially F shape.
(Feature 1) Realize antistatic function by securely grounding the conductive sheet 2 through the metal frame 21 (Feature 2) Enable uniform connection using the precisely processed metal frame 21 Therefore, it is possible to suppress the occurrence of display unevenness and to ensure long-term adhesion reliability between the panel and the structure. (Feature 3) The metal frame 21 is connected to the side surface of the conductive sheet 2 and the back surface side of the front polarizing plate 3a. This eliminates the need to bend the end portion of the metal frame 21 to the surface portion of the liquid crystal display device (that is, the surface end portion of the front polarizing plate 3a), thereby realizing a narrow frame structure.
(Feature 4) By providing the opening 21a in the metal frame 21, the COF wiring on the back substrate 1b can be easily pulled out to the outside.

The liquid crystal display device shown in FIG. 1 can be manufactured by the following procedure.
(Procedure 1) The panel side is manufactured by sequentially laminating the front polarizing plate 3a, the conductive sheet 2, the front substrate 1a, the back substrate 1b, and the back polarizing plate 3b. Here, the wiring connected to the external signal is already connected to the COF at the end of the back substrate 1b.
(Procedure 2) The light source side provided with the light guide plate 11 on the back cover 12 is manufactured.
(Procedure 3) The panel side manufactured according to Procedure 1 and the light source side manufactured according to Procedure 2 are connected via the adhesive 22 with the metal frame 21 having a substantially F shape, and connected to the COF. The drawn wiring is pulled out through the opening 21a.

  By having such a configuration, the conductive sheet 2 provided on the surface side of the liquid crystal display device is connected to the ground via a metal frame 21 having a substantially F shape, thereby preventing charging. Can do.

  Further, the metal frame 21 having the substantially F-shape is connected to the back side and can be connected to the ground without covering the front-side end portion of the front polarizing plate 3a. A frame can be realized.

  Furthermore, the connection between the panel and the structure can be made uniformly through the metal frame 21 having the substantially F shape, and the end of the panel that receives the most load is supported by the metal frame 21. be able to. As a result, the occurrence of display unevenness can be suppressed and long-term adhesion reliability can be ensured. Furthermore, by using the opening 21a provided in the metal frame 21 having the substantially F shape, the COF wiring can be easily taken out.

  As described above, according to the first embodiment, a metal frame having a substantially F shape is used for connection between the panel of the liquid crystal display device and the structure. As a result, the antistatic function of the conductive sheet is realized, display unevenness is suppressed, long-term adhesion reliability between the panel and the structure is ensured, the display area is narrowed, and the external connection is easy. It is possible to obtain a liquid crystal display element and a method of manufacturing a liquid crystal display device that enable the above.

  DESCRIPTION OF SYMBOLS 1a Front substrate, 1b Back substrate, 2 Conductive sheet, 3a Front polarizing plate, 3b Rear polarizing plate, 11 Light guide plate, 12 Back cover, 21 Metal frame, 21a Opening part, 22 Adhesive.

Claims (5)

A liquid crystal display device including a panel provided on the front side and a light source unit provided on the back side,
The panel is configured by sequentially laminating a front polarizing plate, a conductive sheet, a front substrate, a back substrate, and a back polarizing plate, and at a panel end, a back end portion of the front polarizing plate, and a back substrate It is laminated so that the front end and back end are exposed,
The light source unit includes a light guide plate on a back cover,
In the panel end portion, the rear end portion of the front polarizing plate, the side surface of the conductive sheet and the front substrate, the front end portion and the rear end portion of the rear substrate, and the back cover constituting the light source unit A liquid crystal display device further comprising a metal frame that is substantially F-shaped so as to be connected across the side surface of the substrate, is made of a conductive metal material, and is connected to ground. The liquid crystal display device according to claim 1.
The liquid crystal display device, wherein the metal frame includes an opening for pulling out a wiring connected to a COF provided on an end of the back substrate. The liquid crystal display device according to claim 1 or 2,
The metal frame is electrically conductive at the panel end, the back end of the front polarizing plate, the side surfaces of the conductive sheet and the front substrate, the front end and the back end of the back substrate, respectively. A liquid crystal display device connected via an adhesive or conductive double-sided tape. The liquid crystal display device according to any one of claims 1 to 3,
The said conductive sheet is comprised with either the transparent conductive film or the ITO film | membrane. Liquid crystal display device. A method of manufacturing a liquid crystal display device comprising a panel provided on the front side and a light source unit provided on the back side,
A front polarizing plate, a conductive sheet, a front substrate, a rear substrate, and a rear polarizing plate are sequentially laminated, and at the panel end, a rear end portion of the front polarizing plate and a front end portion and a rear end portion of the rear substrate are Manufacturing the panel by stacking so as to be exposed;
Producing the light source unit by comprising a light guide plate on the back cover; and
In the panel end portion, the rear end portion of the front polarizing plate, the side surface of the conductive sheet and the front substrate, the front end portion and the rear end portion of the rear substrate, and the back cover constituting the light source unit And a step of collectively connecting the side surfaces to the ground using a substantially F-shaped frame made of a conductive metal material.

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