JP2002090719A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device capable of improving picture display quality and reliability by suppressing light leakage of backlight light between a liquid crystal display element and a metal frame. SOLUTION: The liquid crystal display element is manufactured by utilizing two sheets of electrode substrates placed opposite to each other, by aligning outside end parts of the electrode substrates with each other, by sticking the substrates together with a sealant and by forming a first light shielding part 4. A second light shielding film 6b is formed on a position overlapping with the first light shielding part 4 and not overlapping with a picture display part. The second light shielding film 6b is formed by applying thereto a thermosetting resin layer to which a black pigment is added and by hardening it by heating.

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 for displaying an image with a back light source such as a backlight using a liquid crystal display element of a chip-on-glass type or a tape carrier package type.

[0002]

2. Description of the Related Art In recent years, a liquid crystal display device used as an image display device has been required to have high display quality and high reliability, and liquid crystal display devices such as a tape carrier package system and a chip-on-glass system have been used. An apparatus configured to display an image using the liquid crystal display element is widely used.

A conventional liquid crystal display device as described above will be described below with reference to the drawings.

FIG. 7 is a plan view showing the structure of a liquid crystal display element and a metal frame in a conventional liquid crystal display device.
Shows a cross-sectional view taken along the line III-III in FIG. FIG. 9 shows C in FIG.
It is an expanded sectional view of a part.

[0005] As shown in FIG. 7, the liquid crystal display device has a configuration in which a liquid crystal display element 1 to which a flexible substrate 3 is connected and a metal frame 2 cover the liquid crystal display element 1. A first light shielding unit 4 is provided around the image display unit 5.

As shown in FIG. 8, the liquid crystal display element 1 has transparent substrates 1a and 1b, transparent electrodes 8a and 8b, and alignment films 9a and 9b formed so as to cover them. The liquid crystal display element 1
Has its space held by beads 10 and is filled with liquid crystal 11. Also, a seal 1 for enclosing the liquid crystal 11
In 2, the transparent electrodes 1a and 1b are bonded.

The liquid crystal display element 1 includes a polarizing plate 13.
a and 13b are adhered, and the metal frame 2 covers the whole.

[0008]

However, in the conventional liquid crystal display device as described above, the first light shielding portion 4 is provided around the image display portion 5, but the first light shielding portion 4 is provided between the liquid crystal display element 1 and the metal frame 2. Leakage light 7 from backlight source 7 through gap
a and 7c are present. The leakage light 7a is transmitted through the transparent resin film 6a.
As a result, the leaked light 7b which is specularly reflected and attenuated further enters the inside of the liquid crystal display element 1. The leakage light 7b is transmitted to the image display unit 5
, And there is a problem that display quality is deteriorated.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a liquid crystal display device capable of attenuating light leakage and improving display quality and reliability of the device.

[0010]

In order to achieve the above object, a first liquid crystal display device of the present invention uses two opposing electrode substrates, aligns the outer ends of the electrode substrates, and forms a sealing material. And a first light-shielding portion is formed on at least one of the electrode substrates, and the first light-shielding portion is formed at a position overlapping the first light-shielding portion and at a position not overlapping the image display portion. It is characterized in that two light shielding films are formed.

In the above device, it is preferable that the second light-shielding film is a low-reflection film layer having a reflectance equal to or lower than the reflectance of the first light-shielding portion.

In the above apparatus, the second light-shielding film is preferably formed by adding a black pigment to a thermosetting resin base material, applying a pattern by a screen printing method or the like, and then thermosetting.

Next, a second liquid crystal display device of the present invention comprises:
In a liquid crystal display element in which two electrode substrates facing each other are aligned and the electrode substrates are aligned and bonded with a sealing material, a light-shielding portion of the electrode substrate on the color filter side is constituted by at least a double frame, and a pixel display is performed. The first light-shielding part located on the side of the part and the second light-shielding part around the first light-shielding part are arranged with a gap of 0.2 mm or more.

In the above device, it is preferable that a black sealing material is formed in a gap between the first light shielding portion and the second light shielding portion around the first light shielding portion.

It is preferable that the width of the first light-shielding portion and the second light-shielding portion of the color filter is 0.5 mm or more.

The sealing material is preferably formed by adding a black pigment to a thermosetting resin base material, applying a pattern by a screen printing method or the like, and then thermosetting.

It is preferable that the gap between the first light-shielding portion and the second light-shielding portion is filled with a material having a transmittance of 3% or less.

As described above, in the present invention, two light-shielding films are provided in order to suppress light leakage of a backlight light source, thereby improving display quality and realizing high reliability.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a liquid crystal display device according to an embodiment of the present invention will be specifically described with reference to the drawings.

(Embodiment 1) A liquid crystal display device according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a schematic plan view of the liquid crystal display device according to the first embodiment. FIG. 2 is a sectional view taken along the line II of FIG. FIG. 3 is an enlarged sectional view of a portion A in FIG. This liquid crystal display device, as shown in FIG.
The liquid crystal display element 1 is connected to a flexible substrate 3 and is covered with a metal frame 2. A color filter BM (first light-shielding portion) 4 and a second light-shielding portion 6b outside the color filter BM (first light-shielding portion) are formed around the image display portion 5.

As shown in FIG. 2, the liquid crystal display element 1 has transparent substrates 1a and 1b, transparent electrodes 8a and 8b, and alignment films 9a and 9b formed so as to cover them. In the liquid crystal display element 1, the space is held by beads 10, and the liquid crystal 1
1 is filled. The transparent substrates 1a and 1b are bonded together by a seal 12 for enclosing the liquid crystal 11.

The liquid crystal display element 1 includes a polarizing plate 13.
a and 13b are adhered, and the second light-shielding film 6 is formed on at least one of the electrode substrates 1 at a position overlapping the first light-shielding portion 4 and at a position not overlapping the image display portion 5. Further, the second light-shielding film is formed of the transparent electrode 1a or 1a.
Even if it is formed on either one of b, the positional relationship with the first light shielding film is the same. Further, even when the first light shielding film 4 is not provided, the second light shielding part 6b is formed at a position where the image display part does not overlap. The second light-shielding portion 6b satisfies the reflectance of the first light-shielding portion, for example, a low reflectance of 3% or less, and is an electrically insulating film. The second light-shielding film 6 is made of a thermosetting resin (for example, an acrylic resin to which a cross-linking component is added) and has a black pigment (for example, carbon black) added thereto in an amount of at least 1% by weight of the substrate. The application method is, for example, pattern application by a screen printing method or the like, followed by baking in a thermosetting oven to form. The thickness of the light shielding film 6 is preferably about 0.7 to 1.1 μm, and the width is preferably about 0.5 to 1.0 mm.

The low-reflection film layer of this embodiment is
As shown in FIG. 3, even if the leakage light 7a, 7b, 7c of the backlight enters, the light can be attenuated, and the light can be prevented from entering the transistor. As a result, the display quality of the device can be improved and high reliability can be realized by this suppressing action.

(Embodiment 2) A liquid crystal display device according to Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 4 is a schematic plan view of the liquid crystal display device according to the second embodiment. FIG. 5 is a sectional view taken along the line II-II in FIG. FIG. 6 is an enlarged sectional view of a portion B in FIG.

As shown in FIG. 4, the liquid crystal display device has a structure in which a liquid crystal display element 1 to which a flexible substrate 3 is connected and a metal frame 2 cover the liquid crystal display element. A color filter BM (first light shielding unit) 1 is provided around the image display unit 5.
4a and the 2nd light-shielding part 14b are comprised by the double frame.

As shown in FIG. 5, a first light-shielding portion 14a located on the pixel display portion side and a second light-shielding portion 1 located around the first light-shielding portion 14a
4b has a gap 15 of 0.2 mm or more. The gap 15 is a minimum dimension for maintaining the adhesion of the sealing material to the transparent substrate 1a. If the gap is less than 0.2 mm, the adhesion strength decreases, and the required adhesion strength of 0.2 kgf / cm ² or more cannot be maintained, and peeling may occur.

The first light-shielding part 14a or the second light-shielding part 14
b is formed with a width of 0.5 mm or more. When the seal 12 is disposed at the center of the gap 15 having a width of 0.2 mm, the seal 12 protrudes from the end of the light-shielding portion 14 b when the finish of the seal 12 is 0.6 mm at maximum on one side. Not the minimum width. In addition, the light shielding portion 14
a and 14b maintain the performance of at least a reflectance of 3% or less.

In the liquid crystal display element 1 shown in FIG. 5, transparent substrates 1a and 1b, transparent electrodes 8a and 8b, and alignment films 9a and 9b are formed so as to cover them. The liquid crystal display element 1
Has its space held by beads 10 and is filled with liquid crystal 11. The transparent electrodes 1a and 1b are attached to each other with a seal 12 containing a black pigment for enclosing the liquid crystal 11. As in the first embodiment, the seal 12 has a black pigment added to the thermosetting resin base material, and is maintained so that the transmittance at least in the BM gap 13 is 3% or less.

The seal 12 is thermally cured after pattern application by a screen printing method or the like. Also,
The liquid crystal display element 1 has polarizing plates 13a and 13b attached thereto.

In such a configuration, even if the leakage light 7a, 7b of the backlight enters, the light is blocked, and the image display unit 5
To prevent light from entering the transistor.

Also, the seal 1 is made using the BM gap 15.
2 has an effect of improving adhesion by directly contacting the transparent electrode substrate 1a. As a result, the display quality of the device can be improved and high reliability can be realized.

[0032]

As described above, according to the present invention, light leakage of the backlight from the gap between the image display element and the metal frame can be suppressed, and the display quality and reliability of the device can be improved. .

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II of FIG. 1;

FIG. 3 is an enlarged sectional view of a portion A in FIG. 2;

FIG. 4 is a schematic plan view of a liquid crystal display device according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view taken along the line II-II of FIG. 4;

FIG. 6 is an enlarged sectional view of a portion B in FIG. 5;

FIG. 7 is a schematic plan view of a conventional liquid crystal display device.

8 is a cross-sectional view taken along the line III-III of FIG. 7;

9 is an enlarged sectional view of a portion C in FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal display element 1a Transparent substrate 1b Transparent substrate 2 Metal frame 3 Flexible substrate 4 Color filter BM (1st light shielding part) 5 Image display part 6a Transparent resin film 6b Second light shielding part 7 Backlight surface light sources 7a, 7b, 7c Leakage light 8a, 8b Transparent electrode 9a, b Alignment film 10 Bead 11 Liquid crystal 12 Seal part 13a, 13b Polarizer 14a First light shielding part 14b Second light shielding part 14b 15 Gap

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H089 LA41 MA03Y MA05Y NA41 PA15 PA18 QA05 TA12 TA13 2H091 FA02Y FA34Y FA34Z FB03 FB12 FB13 FC12 FC22 FD01 FD03 FD06 GA09 LA03

Claims (8)

[Claims] 1. A liquid crystal display device using two opposing electrode substrates, aligning the outer ends of the electrode substrates, bonding them together with a sealing material, and forming a first light-shielding portion on at least one of the electrode substrates. Wherein a second light-shielding film is formed at a position overlapping with the first light-shielding portion and not overlapping with the image display portion. 2. The liquid crystal display device according to claim 1, wherein the second light shielding film is a low reflection film layer having a reflectance equal to or lower than a reflectance of the first light shielding portion. 3. The liquid crystal display device according to claim 1, wherein the second light-shielding film is formed by adding a black pigment to a thermosetting resin substrate, applying a pattern by screen printing or the like, and then thermosetting. 4. A liquid crystal display element in which two electrode substrates opposed to each other are aligned with each other and bonded by a sealing material, wherein a light shielding portion of the electrode substrate on the color filter side is constituted by at least a double frame. A liquid crystal display device, wherein a first light-shielding portion located on the pixel display portion side and a second light-shielding portion around the first light-shielding portion are arranged with a gap of 0.2 mm or more. 5. The liquid crystal display device according to claim 4, wherein a black sealing material is formed in a gap between the first light shield and the second light shield around the first light shield. 6. The liquid crystal display device according to claim 4, wherein the width of the first light-shielding portion and the second light-shielding portion of the color filter is 0.5 mm or more. 7. The liquid crystal according to claim 4, wherein the sealing material is formed by adding a black pigment to a thermosetting resin base material, applying a pattern by screen printing or the like, and then thermosetting. Display device. 8. The gap between the first light-shielding portion and the second light-shielding portion is filled with a material having a transmittance of 3% or less.
8. The liquid crystal display device according to any one of items 1 to 7.