JPH11202320A - Liquid crystal display - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a liquid crystal display device that can be designed in consideration of productivity and can be smaller than the external dimensions of the liquid crystal display panel without changing the display screen size of the liquid crystal display panel. provide. SOLUTION: A first substrate and a second substrate are connected to the first substrate.
A liquid crystal display device having a liquid crystal display element which is bonded by a sealant formed at an edge portion between the first substrate and the second substrate, and in which liquid crystal is sealed between the first substrate and the second substrate. A second substrate of the liquid crystal display device includes a second glass substrate, a color filter layer formed on the second glass substrate, and a second filter substrate on the color filter layer. In a liquid crystal display device having a protective film formed over the entire surface, the protective film on the edge of the second substrate is removed in a frame shape to form a groove, and the sealant is provided in the groove.

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 used for a personal computer, a work station, and the like, and more particularly, to a technique effective when applied to a narrow frame of the liquid crystal display device.

[0002]

2. Description of the Related Art A simple matrix type liquid crystal display device or an active matrix type liquid crystal display device having an active element (for example, a thin film transistor) for each pixel and switchingly driving the active element is used as a display device of a notebook personal computer or the like. Widely used. One of the active matrix type liquid crystal display device, TFT (T hin F i
lm T ransister) mode liquid crystal display panel and (TFT-LCD), a drain driver disposed above the liquid crystal display panel, liquid crystal TFT type and a gate driver and the interface unit are arranged on the side surface of the liquid crystal display panel Display modules are known.

The TFT type liquid crystal display panel has a first
A first substrate (TFT substrate) in which a thin film transistor, a transparent pixel electrode, a protective film, and an alignment film are sequentially laminated on a transparent glass substrate (lower glass substrate), and a second transparent glass substrate (upper glass substrate) A second substrate (color filter substrate) on which a color filter layer, a protective film, a common transparent electrode (common electrode), and an alignment film are sequentially laminated;
Liquid crystal sealed between the substrate and the color filter substrate,
A sealing agent provided along the entire periphery of the TFT substrate and the color filter substrate. In this liquid crystal display panel, after a TFT substrate and a color filter substrate are separately formed, a sealing agent is applied along the entire peripheral portion of the color filter substrate, and the TFT substrate is superimposed thereon, and heated and heated. By pressing, the two are adhered by the sealant. Thereafter, liquid crystal is sealed through the sealing hole provided in the sealant, the sealing hole is sealed, and a polarizing plate is provided on the surface of the TFT substrate and the color filter substrate. Such a technique is described in, for example, Japanese Patent Application Laid-Open No. 5-257141.

[0004]

In recent years, in a liquid crystal display device such as a TFT type liquid crystal display module, the display screen is becoming larger and larger, and the size of the display screen is increased. In order to eliminate the problem and bring about an aesthetic appearance as a display device, there is a demand for a region other than the display region of the liquid crystal display device, that is, a frame portion as small as possible (narrower frame). In order to cope with this narrowing of the frame, the outer dimensions of the liquid crystal display panel are also reduced without changing the display screen size of the liquid crystal display panel, that is, the frame portion of the liquid crystal display panel is reduced. Need to do that,
(1) Improve the alignment film printing accuracy and reduce the frame size.
(2) Improving the cutting accuracy of the transparent glass substrate of the liquid crystal display panel to reduce the outer dimensions of the liquid crystal display panel, and (3) reducing the line width of the sealant to reduce the frame size. However, these methods are mainly studied for reviewing design dimensions, and there is a problem that productivity may be reduced by improving various accuracy. Further, in the conventional liquid crystal display panel, even if the line width of the sealant is reduced, the external dimensions of the liquid crystal display panel cannot be reduced too much due to the variation in the swelling of the sealant when the liquid crystal display panel is manufactured. There were also points.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a liquid crystal display device which can be designed in consideration of productivity.
Without changing the display screen size of the LCD panel,
It is an object of the present invention to provide a technology capable of reducing the outer dimensions of a liquid crystal display panel. The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0006]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows. That is, the present invention provides the first substrate and the second substrate.
A liquid crystal display in which liquid crystal is sealed between the first substrate and the second substrate by bonding a sealant formed on an edge portion between the first substrate and the second substrate. A liquid crystal display device including an element, wherein a first substrate of the liquid crystal display element includes a first glass substrate, a color filter layer and a light shielding film formed on the first glass substrate, In a liquid crystal display device having a protective film formed over the entire surface of the first substrate on a filter layer and a light-shielding film, a groove is formed by removing the protective film on the edge of the first substrate in a frame shape. And the sealing agent is provided in the groove.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a TFT type liquid crystal display module will be described below in detail with reference to the drawings. In all the drawings for describing the embodiments, components having the same function are denoted by the same reference numerals, and
The description of the repetition is omitted.

FIG. 1 is a cross-sectional view of a principal part showing a schematic cross-sectional structure of a periphery of a liquid crystal display panel of a liquid crystal display device according to an embodiment of the present invention, and FIG. It is a top view of a liquid crystal display panel.

As shown in FIGS. 1 and 2, a liquid crystal display panel (liquid crystal display element) according to the present embodiment has a TFT substrate (A).
R) and the color filter substrate (CF) with a sealant (S
L), and liquid crystal (LC) is sealed between the TFT substrate (AR) and the color filter substrate (CF). Here, the color filter substrate (CF) is a second transparent glass substrate (upper transparent glass substrate) (SUB2)
And red, green, and blue color filter layers (FIL (R), FIL (G), FI) formed on the second transparent glass substrate.
L (B)) and the light-shielding film (BM), and the protective film (overcoat layer) formed on the color filter layers (FIL (R), FIL (G), FIL (B)) and the light-shielding film (BM) (OC), a second transparent electrode (common electrode) (ITO2) formed on the protective film (OC), and an alignment film (ORI2) formed on the second transparent electrode (ITO2). You.

The TFT substrate (AR) includes a first transparent glass substrate (lower transparent glass substrate) (SUB1) and a gate signal line and a gate insulating film formed on the first transparent glass substrate (SUB1). Thin film transistors, video signal lines,
Although composed of a pixel electrode, a protective film, and an alignment film, FIG. 1 illustrates only the first transparent glass substrate (SUB1),
Other parts are omitted. Also, in FIG.
OL1 is the first polarizing plate (lower polarizing plate), and POL2 is the second polarizing plate.
(Upper polarizing plate).

In the present embodiment, the protective film (OC) on the edge of the second transparent glass substrate (SUB2) is removed in a frame shape to form a groove (MZ), and the inside of the groove (MZ) is formed. , A sealant (SL) is disposed. This groove (MZ)
When, for example, a photocurable acrylic resin or an epoxy resin is used as the protective film (OC),
It is formed by removing the protective film (OC) in the groove (MZ) portion by a photolithography technique. The liquid crystal display panel of the present embodiment is produced, for example, by the following steps. (A) TFT substrate (AR) and color filter substrate (C
And F) separately. (B) Next, a spacer is disposed on the entire surface of the color filter substrate (CF), and a sealing agent (SL) made of a thermosetting epoxy resin material is formed along the entire peripheral edge of the color filter substrate (CF). Is applied by, for example, a screen printing method. (C) Next, a TFT substrate (AR) is superimposed on a color filter substrate (CF) on which spacers are arranged on the entire surface and a sealing agent (SL) is applied along the entire periphery thereof. The sealant (SL) is cured by heating and pressurizing, and the color filter substrate (CF) and the TFT substrate (A
R) with an adhesive seal. (D) Next, liquid crystal (LC) is injected from a liquid crystal sealing port (SE) provided in a part of the sealant (SL), and the liquid crystal sealing port (SE) is sealed with an epoxy resin or the like. (E) Next, the glass substrates (SUB1, SUB2) of the TFT substrate (AR) and the color filter substrate (CF) are cut, and the polarizing plates (POL1, POL1, P2) are provided on both sides of the liquid crystal display panel.
(OL2).

FIG. 3 is a schematic diagram for explaining deformation (bulging) of the sealing agent (SL) when the TFT substrate (AR) and the color filter substrate (CF) are bonded and sealed with the sealing agent (SL). FIG. 3A shows the sealant (S
L) A schematic sectional view showing the width (W1) of the sealing agent (SL) after application, and FIG. 3 (b) shows the width (W) of the sealing agent (SL) after heating and pressurizing in the manufacturing process (c). W2) is a schematic cross-sectional view, and FIG. 3 (c) is a diagram for explaining variation in the swelling of the sealant (SL) after heating and pressurizing in the manufacturing process (c).

In the manufacturing step (c), the TFT substrate (AR) and the color filter substrate (CF) are superposed, and then the TFT substrate (AR) and the color filter substrate (CF) are pressed and heated. The sealing agent (SL) is used for bonding. At this time, the width of the sealing agent (SL) expands from the width (W1) shown in FIG. 3A to the width (W2) shown in FIG. spread). The swelling of the sealant (SL) has a variation as shown by a dotted line in FIG. That is, the line width of the sealant (SL) after being heated and pressurized in the manufacturing process (c) becomes wavy.
Therefore, in the conventional liquid crystal display panel, it is necessary to absorb the variation in the swelling of the sealant (SL), so that the glass substrate (SUB) of the color filter substrate (CF) is used.
When cutting 2), there is a problem that the distance (t in FIG. 3C) between the sealant (SL) and the end of the color filter substrate (CF) cannot be reduced too much. There is a limit to narrowing the frame of the liquid crystal display panel.

However, in the present embodiment, the groove (MZ) in which the protective film (OC) is removed in a frame shape is formed, and the sealant (SL) is arranged in the groove (MZ). In the manufacturing process (c), the TFT substrate (A
R) and the color filter substrate (CF) are overlapped and pressurized and heated, and when the TFT substrate (AR), the color filter substrate (CF) and the sealant (SL) are bonded, the sealant (SL) is , An outer protective layer (OC), that is, a protective layer (O) formed at an end of the color filter substrate (CF).
C) restricts its swelling, and sealant (SL)
Can swell inside the liquid crystal display panel, and the swelling of the sealant (SL) at the end of the color filter substrate (CF) can be reduced.

FIG. 4 shows a TFT substrate (AR) and a color filter substrate (CF) in a completed state of the present embodiment.
FIG. 7 is a cross-sectional view of relevant parts showing a state after adhesive sealing is performed with a sealing agent (SL). That is, in the completed state of the liquid crystal display panel of the present embodiment, as shown in part a of FIG. 4, the sealant (SL) at the end of the color filter substrate (CF) is
The sealing agent (SL) on the liquid crystal display panel side is in close contact with the outer protective layer (OC), and as shown in part c of FIG.
Is between an inner protective layer (OC), that is, a protective layer (OC) formed inside the color filter substrate (CF).
It is formed with a certain margin. Here, when the sealant (SL) is applied in the groove (MZ), it is not possible to determine the amount and position of application in such a manner that the liquid crystal display panel is completed as shown in FIG. Needless to say.

Therefore, in this embodiment, the color filter is not affected by the swelling of the sealing agent (SL) when the TFT substrate (AR) and the color filter substrate (CF) are bonded by the sealing agent (SL). The distance (t) from the edge of the substrate (CF) to the sealant (SL) can be guaranteed. This distance (t) is the cutting position of the liquid crystal display panel (or the transparent glass substrate (SUB2)),
Therefore, in the present embodiment, the transparent glass substrate (SU
The margin of the cutting tolerance in B2) can be widened, and the productivity can be improved. Further, according to the present embodiment, the distance (t) can be reduced, and the line width of the sealant (SL) can be reduced, so that the frame size of the liquid crystal display panel can be reduced. It is easily adaptable to narrowing the frame of the liquid crystal display panel. According to the present embodiment, the value of t can be reduced to, for example, 0.1 mm.

In the present embodiment, the protective layer (OC)
Is removed in the shape of a frame to form a groove (MZ).
Since the sealant (SL) is arranged in Z),
It is possible to improve the adhesion of the sealing agent (SL). Further, since the light shielding film (BM) is formed in the groove (MZ), it is possible to prevent the light from the backlight from leaking to the display surface of the liquid crystal display panel through the sealant (SL). Alternatively, it is possible to prevent external light from leaking into the liquid crystal display panel through the sealant (SL). In FIG. 1, the light-shielding film is provided only in a part of the groove (MZ). However, the light-shielding film may be provided in the entire area of the groove (MZ). Is most suitable. In the above embodiment, the case where the present invention is applied to a TFT type active liquid crystal display module has been described. However, the present invention is not limited to this. Needless to say, it can be applied to modules.

As described above, the invention made by the present inventor is:
Although a specific description has been given based on the above-described embodiment, the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the gist of the invention.

[0019]

The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows. (1) According to the present invention, when the first substrate and the second substrate are bonded to each other with the sealant, the variation in the swelling of the sealant at the end of the substrate can be reduced. 2
The margin of the cutting tolerance of the transparent glass substrate can be widened, and the productivity can be improved. (2) According to the present invention, when the first substrate and the second substrate are bonded to each other with the sealant, the variation in the swelling of the sealant at the end of the substrate can be reduced. Can be reduced, and the liquid crystal display element can be easily adapted to a narrower frame. (3) According to the present invention, since the protective layer is removed in the shape of a frame to form a groove, and the sealant is arranged in the groove, the adhesion of the sealant can be improved. .

[Brief description of the drawings]

FIG. 1 is a main part sectional view showing a schematic sectional structure of a peripheral portion of a liquid crystal display panel of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a plan view of the liquid crystal display panel according to the embodiment of the present invention.

FIG. 3 is a schematic diagram for explaining deformation of a sealant when a TFT substrate and a color filter substrate are bonded and sealed with the sealant.

FIG. 4 is a cross-sectional view of a main part showing a state after the TFT substrate and the color filter substrate are bonded and sealed with a sealant in a completed state of the present embodiment.

[Explanation of symbols]

AR: TFT substrate, CF: Color filter substrate, SUB
... Transparent glass substrate, POL ... Polarizing plate, LC ... Liquid crystal, FI
L: color filter layer, OC: protective film, BM: light shielding film,
ITO: transparent electrode, ORI: alignment film, SL: sealant,
SE: liquid crystal sealing port, MZ: groove.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuya Kawamura 3300 Hayano Mobara-shi, Chiba Electronic Device Division, Hitachi, Ltd.

Claims (3)

[Claims] A first substrate provided on the first substrate and a second substrate provided on the first substrate;
A liquid crystal display device having a liquid crystal display element which is bonded by a sealant formed at an edge portion between the first substrate and the second substrate, and in which liquid crystal is sealed between the first substrate and the second substrate. The second substrate of the liquid crystal display element includes a second glass substrate, a color filter layer and a light-shielding film formed on the second glass substrate, and a color filter layer and a light-shielding film formed on the second glass substrate. A protective film formed over the entire surface of the second substrate, wherein the protective film on the edge of the second substrate is removed in a frame shape to form a groove; A liquid crystal display device comprising: 2. The liquid crystal display device according to claim 1, wherein the sealant is formed in close contact with an outer protective film. 3. The light-shielding film according to claim 1, wherein a light-shielding film is provided on the first glass substrate in the groove or on a part of the first glass substrate in the groove. Liquid crystal display device.