JP3259899B2 - Liquid crystal display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device having a liquid crystal layer sandwiched between flexible film substrates, and more particularly to a liquid crystal display device in which cracks or the like do not occur in electrode terminals of the liquid crystal display device. .

[0002]

2. Description of the Related Art A liquid crystal display device using a polymer film substrate has the advantages that it is thinner and lighter than a device formed of a glass substrate, and that it can be easily bent. An electrical connection between a liquid crystal display element using the polymer film substrate and a drive circuit thereof is generally made by a method of connecting via a conductive rubber, a method of connecting via an HSC (Heat Seal Connector), an FPC (Flexible Printed Circuit Board) ) Via an ACF (anisotropic conductive film).

On the other hand, as the polymer film substrate, polyethylene terephthalate, polycarbonate, polyether sulfone, generally having a thickness of 50 to 300 μm is used.
Substrates in which a gas barrier material or a hard coat material is coated on a film such as polyarylate are used. An electrode such as ITO is formed on these substrates and used. Such a thin substrate is used. When the FPC is connected to the terminal via conductive rubber, HSC or ACF, there is a problem that the electrode terminal is bent by heat and / or pressure, cracks are generated, and disconnection easily occurs.

In order to solve the above problem, it has been proposed to extend the polarizing plate on the back surface of the electrode terminal to solve the problem of the disconnection (Japanese Patent Laid-Open No. 7-43697). However, in the liquid crystal display device manufactured by the above method, since the polarizing plate extends to the lower side of the electrode portion on only one side, the stress balance due to the expansion and contraction of the temperature and humidity of the polarizing plate in a reliability test such as high temperature, high humidity and high temperature. Locally collapsed, warpage and distortion of the connection part increased, and the connection resistance increased and peeling and disconnection were promoted.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal display device in which the electrode terminal portion after the connection of the electrodes is warped, the stress against distortion is reduced, and the connection reliability is improved.

[0006]

According to the present invention, a liquid crystal layer is sandwiched between a pair of flexible film substrates provided with electrodes, a polarizing plate is provided outside the substrate, and one of the substrates is provided with a polarizing plate. A notch portion for taking out an electrode is formed on a part of the side, and the outer shape of a polarizing plate provided outside the substrate having the notch portion is formed along the outer shape of the substrate. In the above, an electrode terminal portion is provided in a liquid crystal display region, and both substrates are end-sealed such that a region where a cutout portion for an electrode takeout portion can be formed is formed on one side thereof. By providing a liquid crystal display element having a structure in which a region is cut out, the problem of the related art can be solved.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of an example of the liquid crystal display device of the present invention, and FIG. 2 is a plan view of the liquid crystal display device shown in FIG. 1 and 2, 1 and 11 are polymer film substrates, 2 is a sealing material, 3 is a liquid crystal, 4 is a gap material, 5 is an electrode terminal portion, and 6 and 7 are polarizing plates formed outside the polymer film substrate 1. It is. In the liquid crystal display device shown in FIGS. 1 and 2, a liquid crystal layer 3 is sandwiched between a pair of polymer film substrates 1 and 11 having electrodes such as ITO, and polarizing plates 6 and 7 are attached to the outside of the substrates 1 and 11. One end side of the pair of flexible film substrates 1 and 11 extends outside the liquid crystal display area, and an electrode terminal portion 5 is provided on one of the substrates 1 of the extended portion. Further, a part for taking out an electrode is provided on a part of the side of the substrate 11 of the other extension part. The polarizing plate 6 is formed in accordance with the shape of the substrate 1 having the cutout.

FIG. 3 is a schematic plan view showing the structure of the above-mentioned liquid crystal display device of the prior art. In this known liquid crystal display device, both the polarizing plates 6 and 7 of the liquid crystal display device of the present invention shown in FIGS. 1 and 2 are extended, while only the polarizing plate 7 is extended. As described above, when only the polarizing plate 7 is extended, when the liquid crystal display element is subjected to a storage test under high temperature and high humidity, the polarizing plate and the polymer film substrate usually expand and contract to generate stress, and Although the extension part distorts the balance of stress as compared with the other parts and causes warpage and distortion, when both the polarizing plates 6 and 7 are extended as shown in FIGS. 1 and 2, it is possible to reduce the stress imbalance. Therefore, warpage and distortion can be reduced.

FIG. 4 is a schematic plan view of another example of the liquid crystal display device of the present invention. In the liquid crystal display element, a liquid crystal layer is sandwiched between the substrates, and both the substrates are end-sealed so that a region where a cutout portion for an electrode extraction portion can be formed on one side is formed. It has a structure in which a region is cut out. In the liquid crystal display element shown in FIG. 4, when the electrode lead-out portion is relatively small with respect to the length of the side of the substrate on which the electrode lead-out portion is provided, an electrode terminal portion is formed in the display region, and the notch is formed. By providing the polarizing plate along the outer shape of the substrate on which the portion is formed, the effect of the present invention can be further improved.

[0010] By covering the edge portion of the thin polymer film substrate of the liquid crystal display element of the present invention with a polarizing plate, it is possible to reinforce the impact applied to the liquid crystal display element and the like, and therefore, the handling is easy. This has the advantage of being able to As the flexible film substrate used in the liquid crystal display device of the present invention, a substrate obtained by coating a gas barrier material or a hard coat material on a film of polyethylene terephthalate, polycarbonate, polyether sulfone, polyarylate or the like having a thickness of 50 to 300 μm is generally used. No. Further, as the sealing material, the liquid crystal, the gap material, and the electrode terminal, those conventionally used in liquid crystal display elements can be used. Hereinafter, examples of the present invention will be described.

[0011]

【Example】

Example 1 A polycarbonate film (thickness: 120 μm) coated with a gas barrier layer and a solvent-resistant layer was used as a substrate.
One having a TO electrode formed thereon was used. It was attached to the outside of this substrate. However, the polarizing plate on the electrode part take-out side should follow the outer shape of the substrate in which a notch part for taking out the electrode as shown in FIG. 2 was formed in a part of one side of the substrate to which the polarizing plate was attached. It is attached. Using a substrate on which the polarizing plate is attached, sandwiching a liquid crystal layer, and having an outer shape of 30 m
An mx 60 mm liquid crystal display device was manufactured. HSC was thermocompression-bonded to the electrode terminals of the liquid crystal display, and the other was connected to a drive circuit. The above liquid crystal display element was subjected to high temperature and high humidity (40 ° C, 90%
RH), high temperature (60 ° C), low temperature (-20 ° C)
A 10-cycle reliability test was performed under a temperature cycle (65 ° C. to −10 ° C.) environment of 40 hours. As a result, no significant warping or distortion was observed in the connection portion under any environment, and no change was observed in the connection resistance, and good results were obtained.

Example 2 After sandwiching a liquid crystal layer using the substrate obtained by attaching a polarizing plate to the substrate of Example 1, both substrates are end-sealed and the external shape 3
A 0 mm × 80 mm liquid crystal element was produced. However,
The polarizing plate on the side from which the electrode portion is taken out is attached along a contour of the substrate in which a notch portion for taking out the electrode as shown in FIG. 4 is formed on a part of one side of the substrate to which the polarizing plate is attached. It is a thing. HSC was thermocompression-bonded to the electrode terminals of the liquid crystal display element, and the other was connected to a drive circuit. This liquid crystal display element is reliable for 240 hours under high temperature and high humidity (40 ° C., 90% RH), high temperature (60 ° C.), low temperature (−20 ° C.) environment and 10 cycles under temperature cycle (65 ° C. to -10 ° C.) environment. A sex test was performed. As a result, in any environment, the connection portion was not warped or distorted, and no change was observed in the connection resistance, and good results were obtained.

[0013]

According to the present invention, it is possible to prevent disconnection of an electrode terminal due to an external force at the time of connection of an extraction electrode, and to reduce stress on an electrode terminal portion after connection of the extraction electrode due to warpage and distortion, thereby improving connection reliability. can do.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an example of the liquid crystal display device of the present invention.

FIG. 2 is a plan view of the liquid crystal display device shown in FIG.

FIG. 3 is a schematic plan view of a structure of a known liquid crystal display device.

FIG. 4 is a schematic plan view of another example of the liquid crystal display device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 11 Substrate 2 Sealing material 3 Liquid crystal 4 Gap material 5 Electrode terminal part 6 Polarizing plate 7 Polarizing plate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02F 1/1335 510 G02F 1/1333 500 G02F 1/1345 G02F 1/1339 505

Claims (1)

(57) [Claims] 1. A liquid crystal layer is sandwiched between a pair of flexible film substrates with electrodes, a polarizing plate is provided outside the substrate, and an electrode is provided on a part of a side of one of the substrates. The notch for forming, and the outer shape of the polarizing plate provided outside the substrate on which the notch is formed, in a liquid crystal display element configured along the outer shape of the substrate,
An electrode terminal portion is provided in a liquid crystal display region, and the both substrates are end-sealed so that a region where a cutout portion for an electrode extraction portion can be formed is formed on one side of the substrate. A liquid crystal display device having a cut-out structure.