JPH10333159A - Liquid crystal display - Google Patents

Abstract

(57) [Problem] To provide a liquid crystal display device with improved cell gap accuracy and sealing property. SOLUTION: Inner / outer seal lines 3 and 4 are applied onto glass substrates 1 and 2 with a UV-curable or thermosetting sealant, and a liquid crystal material 5 and a spacer 7 are provided inside the inner peripheral seal lines cured. And the first and second glass substrates 1 and 2 are pressurized to harden the outer peripheral side seal line 4 to join the substrates 1 and 2 together. By forming the inner peripheral side seal line 3 from a material having good slipperiness, the spacer 7 placed on the inner peripheral side seal line 3 slides down, so that the spacer 7 is prevented from remaining on the surface of the inner peripheral side seal line 3. A decrease in cell gap accuracy and sealing performance when joining between 1 and 2 is suppressed.

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 manufactured by using a liquid crystal dropping method.

[0002]

2. Description of the Related Art As is well known, a liquid crystal display device is formed by sealing a liquid crystal material between two glass substrates on which transparent electrodes are formed. The liquid crystal material is accommodated in a space corresponding to the height of a seal line formed by a sealant formed around the opposing surfaces of the two glass substrates, and the two glass substrates are joined by the seal line. FIG. 5 shows a cross-sectional structure of a liquid crystal display device manufactured by a liquid crystal dropping method, which is schematically shown to clearly show each component.

As shown in FIG. 5, a liquid crystal display device 20 comprises:
A liquid crystal material 25 and a spacer 26 are formed by sealing a liquid crystal material 25 and a spacer 26 inside an inner peripheral side sealing line 23 in which the periphery between the opposing surfaces of the two glass substrates 21 and 22 is joined by double sealing lines 23 and 24. The cell gap between the first and second glass substrates 21 and 22 is ensured by the spacer 26, and the liquid crystal material 2 is formed by the double seal lines 23 and 24.
5 is prevented from leaking, and the respective glass substrates 21 and 22 are joined together. The liquid crystal display device 20 is manufactured by a liquid crystal dropping method, and is manufactured by a procedure as shown in FIG.

[0006] As shown in FIG. 6 (a), UV light is applied around the surface of the first glass substrate 21 facing the second glass substrate 22.
A sealing agent using a curable or thermosetting material is applied as the seal line 23. As the sealant, a material that becomes an elastic body after curing is employed. Similarly, as shown in FIG. 6B, the first glass substrate 2 of the second glass substrate 22
A sealing agent using a UV-curable or thermosetting material is applied as a seal line 24 around the surface facing the surface 1.
When the first glass substrate 21 and the second glass substrate 22 are joined, the seal lines 23 and 24 are formed as double seal lines 23 and 24 between the opposing surfaces. Is applied inside.

[0005] Next, the sealing agent applied to the first glass substrate 21 is UV-cured or heat-cured, and while being surrounded by the cured sealing line 23, as shown in FIG.
The liquid crystal material 25 is dropped, and spacers 26 for forming a cell gap between the first glass substrate 21 and the second glass substrate 22 are dispersed. After this, FIG.
As shown in FIG. 2, the first glass substrate 21 and the second glass substrate 22 are overlapped and pressed, and the second glass substrate 22 is pressed.
The first and second glass substrates 21 and 22 are joined by UV-curing or heat-curing the sealant applied to the substrate.

With the above structure, the inner seal line 23
Is formed of an elastic material, the seal between the first and second glass substrates 21 and 22 is brought into close contact with the opposing surface of the second glass substrate 22 by the pressurization between the first and second glass substrates 21 and 22, and the outer seal line is formed. Reference numeral 24 denotes the first and second glass substrates 21 and 22 joined to each other, and the inner peripheral seal line 23 is formed by a double seal.
The leakage of the liquid crystal material 25 sealed therein is prevented.

[0007]

However, as shown in FIG. 7, when the spacers 26 are sprayed, the spacers 26 are easily placed on the inner peripheral side seal line 23, and the first and second spacers are kept in this state. When the glass substrates 21 and 22 are bonded together, the spacer 26 having a diameter (3 to 7 μm) close to its formed thickness (5 to 7 μm) even though the inner peripheral seal line 23 is an elastic body. Cannot be deformed enough to absorb Therefore, the presence of the spacer 26 on the inner peripheral side seal line 23 causes the glass substrate 21,
Not only does the cell gap accuracy between the liquid crystal materials 22 deteriorate, but also the sealing property of the inner seal line 23 is impaired.
There was a problem that leakage of 5 occurred.

An object of the present invention is to provide a liquid crystal display device which prevents a decrease in cell gap accuracy and sealing performance caused by a spacer placed on a seal line.

[0009]

According to a first aspect of the present invention for achieving the above object, two inner and outer seal lines are formed around an opposing surface of two substrates arranged facing each other. In a liquid crystal display device in which a liquid crystal material and a spacer are arranged in an inner peripheral side seal line and substrates are joined by the seal line to seal the liquid crystal material in the seal line, the inner peripheral side seal line is And a silicon-based or fluorine-based sealant.

According to the above configuration, since the inner peripheral side seal line is formed of a silicon-based or fluorine-based sealant, the slipperiness with respect to the spacer formed of the silicon-based material is improved. It is suppressed that the spacer placed on the side seal line remains when the two substrates are joined. Therefore, it is possible to suppress a decrease in the accuracy of the cell gap and a decrease in the sealing performance due to the joining between the substrates while the spacer remains on the inner peripheral side seal line.

Further, according to a second aspect of the present invention, a double seal line on an inner peripheral side and an outer peripheral side is formed around an opposing surface of two substrates disposed facing each other, and a liquid crystal material is formed in the inner peripheral side seal line. And a spacer, and a liquid crystal display device in which the substrates are joined to each other by the seal line to seal the liquid crystal material in the seal line, wherein the inner peripheral seal line is formed by a sealing agent made of a foamed resin or a porous resin. It is characterized by being formed.

According to the above configuration, since the foaming resin or the porous resin forming the inner peripheral side sealing line includes a large number of spaces, the spacer placed on the inner peripheral side sealing line at the time of dispersing the spacers may have two spaces. It is taken into the inner peripheral side seal line by the pressure at the time of joining the two substrates. Therefore, it is possible to suppress a decrease in accuracy of the cell gap and a decrease in sealing performance due to the joining between the substrates while the spacer remains on the surface of the inner peripheral side seal line.

Further, according to a third invention of the present application, a double seal line on the inner peripheral side and the outer peripheral side is formed around the opposing surface of the two substrates arranged facing each other, and a liquid crystal material is formed in the inner peripheral side seal line. And a spacer, and a liquid crystal display device in which liquid crystal material is sealed in the seal line by joining the substrates by the seal line, wherein a cross-sectional shape of the inner peripheral side seal line is formed in a mountain shape. I do.

According to the above configuration, since the spacer placed on the inner peripheral side seal line easily rolls down from the angled inclined surface and does not remain, the spacer remains on the surface of the inner peripheral side seal line. A decrease in cell gap accuracy and sealing performance is suppressed.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention.
In addition, in each figure shown below, in order to clearly show a fine configuration,
The actual state and the dimensional ratio are schematically shown as being different from each other, and the actual dimensions are formed as in the dimension example described in the text. Further, illustration of electrodes and the like formed on the substrate is omitted.

First, a manufacturing method using a liquid crystal dropping method for manufacturing the liquid crystal display device according to the present embodiment will be described. FIG. 1 shows the steps of the manufacturing method in the order of (a) to (f). Each step will be described below in order.

(A) As shown in FIG. 2 (a), an outer-peripheral seal line is applied to a second glass substrate 2 as described below, as shown in FIG. 4 is applied to a position on the inner peripheral side. This sealant
An ultraviolet (UV) curable resin or a thermosetting resin is used, and a material that becomes an elastic body when cured and that does not easily react with the liquid crystal material is used. This inner peripheral side sealing line 3 has a second glass substrate 2 with a line width of 200 μm or less.
Is applied to a thickness greater than the height of the outer peripheral seal line 4. Here, an ultraviolet curable resin is adopted, and an intaglio offset printing is used as a coating method. As a coating method, a method such as screen printing or a dispenser can be used.

(B) Since the inside of the inner peripheral side sealing line 3 formed by the applied sealant becomes a storage portion for the liquid crystal material, it is necessary to cure the liquid crystal material before injecting it. It is cured by irradiating ultraviolet rays.

(C) A predetermined amount of the liquid crystal material 5 is dropped into the inside surrounded by the hardened inner peripheral seal line 3.

(D) Subsequently, spacers 7 for forming a cell gap are sprayed.

(E) Next, as shown in FIG. 2 (b), the second glass substrate 2 coated with a sealant to be the outer peripheral side seal line 4 is overlaid on the first glass substrate 1.

(F) A pressure is applied between the first glass substrate 1 and the second glass substrate 2 and the uncured outer peripheral side sealing line 4 is cured by irradiating ultraviolet rays to the first glass substrate 1. And the second glass substrate 2 are joined. At the time of this pressure joining, since the inner peripheral side seal line 3 is an elastic body,
The spacers 7 are compressed to the diameter of the spacers 7 by the deformation due to the pressure and adhere to the second glass substrate 2, so that the sealing property is improved.

In the above manufacturing method, when the spacer 7 is sprayed in the step (d), the spacer 7 is
If the first and second glass substrates 1 and 2 are joined together as they are on the top, the cell gap accuracy may be reduced,
The occurrence of leakage of the liquid crystal material 5 due to a reduction in the sealing property has been pointed out as a problem of the prior art. The present invention employs the configurations of the following embodiments to solve this problem. The configuration of each embodiment will be described below.

The first embodiment of the present invention uses a silicon (Si) -based or fluorine (F) -based rubber-like resin as a sealant for forming the inner peripheral side seal line 3, and is used when cured. And the spacers 7 formed of silicon dioxide (SiO ₂ ), etc.
The possibility that the spacer 7 remains on the inner peripheral seal line 3 until the glass substrate 2 is joined is greatly reduced, and a decrease in cell gap accuracy is suppressed.

In the second embodiment of the present invention, a foaming resin or a porous resin is used as a sealant for forming the inner peripheral side sealing line 3, and the space for absorbing the spacer 7 when cured is provided. Since there are many, the spacers 7 placed on the surface are taken into the space in the inner peripheral side seal line 3 by the pressure when the second glass substrate 2 is joined, and do not remain on the surface. A decrease in gap accuracy is suppressed.

Further, in the third embodiment of the present invention, as shown in FIG. 3, the inner peripheral side seal line 3 is formed so that the cross-sectional shape of the inner peripheral side seal line 3 becomes a mountain shape.
Is a slope, so that the spherical spacer 7 cannot remain on the inner peripheral side seal line 3. A manufacturing method for forming the cross-sectional shape of the inner peripheral side seal line 3 into a mountain shape is to apply the inner peripheral side seal line 3 a plurality of times by changing the application width by a sealant applying means such as intaglio offset printing. This is to obtain a mountain-shaped cross section.

FIGS. 4A and 4B show a manufacturing method in which a sealant is applied twice by intaglio offset printing. In the case where the height of the inner peripheral side seal line 3 is set to 6 μm, FIG. Application width 100-200 μm by first printing
After applying the sealant 3a to a height of 3 μm and curing it (may be uncured), apply the sealant 3b to the application width of 50 μm and a height of 3 μm by the second printing, and cure it. . As shown in the enlarged view of FIG. 3, the applied sealant has a rounded corner due to its flow and surface tension, so that it has a mountain shape with a gentle slope, and the spacer 7 placed thereon is The spacer 7 does not remain on the inner peripheral side seal line 3 because it easily falls off the inclined surface. By using the material having good slipperiness shown in the first embodiment for the sealant forming the inner peripheral side seal line 3, the effect of dropping the spacer 7 having the mountain-shaped cross-sectional shape becomes more effective.

[0028]

As described above, according to the first aspect of the present invention, by forming the inner peripheral seal line with a silicon-based or fluorine-based sealant, the slipperiness with respect to the spacer formed of a silicon-based material is improved. Therefore, it is possible to prevent the spacer placed on the inner peripheral side seal line from remaining when joining the two substrates when the spacers are sprayed. Therefore, it is possible to suppress a decrease in the accuracy of the cell gap and a decrease in the sealing performance due to the joining between the substrates while the spacer remains on the inner peripheral side seal line.

Further, according to the second aspect of the present invention, since the inner peripheral side sealing line is formed of a foaming resin or a porous resin sealing agent and includes a large number of spaces, the inner sealing line is formed when the spacer is sprayed. The spacer placed on the peripheral seal line is taken into the internal seal line by pressurization at the time of joining the two substrates. Therefore, it is possible to suppress a decrease in the accuracy of the cell gap and a decrease in the sealing performance due to the joining between the substrates while the spacer remains on the surface of the inner peripheral side seal line.

Further, according to the third aspect of the present invention, by forming the cross-sectional shape of the inner peripheral side seal line into a mountain shape,
Since the spacer placed on the inner peripheral side sealing line rolls down from the inclined surface of the chevron and does not remain, the decrease in cell gap accuracy and sealing performance due to the spacer remaining on the surface is suppressed.

[Brief description of the drawings]

FIGS. 1A to 1F are schematic views showing steps of a method for manufacturing a liquid crystal display device according to an embodiment of the present invention.

FIGS. 2A and 2B are plan views for explaining formation of inner and outer seal lines. FIGS.

FIG. 3 is an enlarged sectional view showing a sectional shape of an inner peripheral side seal line according to a third embodiment.

FIGS. 4A and 4B are schematic diagrams illustrating a method of forming an inner peripheral side seal line according to a third embodiment; FIGS.

FIG. 5 is a cross-sectional view illustrating a configuration of a liquid crystal display device manufactured by a liquid crystal dropping method.

FIGS. 6A to 6D are schematic diagrams illustrating a method for manufacturing a liquid crystal display device according to the related art.

FIG. 7 is a schematic diagram illustrating a problem of the related art.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 first glass substrate (first substrate) 2 second glass substrate (second substrate) 3 inner seal line 4 outer seal line 5 liquid crystal material 7 spacer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideki Matsukawa 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] An inner peripheral side and an outer peripheral side double seal line are formed around an opposing surface of two substrates arranged facing each other, and a liquid crystal material and a spacer are arranged in the inner peripheral side seal line. In a liquid crystal display device in which substrates are joined by a seal line and a liquid crystal material is sealed in the seal line, the inner peripheral side seal line is formed of a silicon-based or fluorine-based sealant. Liquid crystal display. 2. An inner peripheral side and an outer peripheral side double seal line are formed around an opposing surface of two substrates arranged facing each other, and a liquid crystal material and a spacer are arranged in the inner peripheral side seal line. In a liquid crystal display device in which a liquid crystal material is sealed in a seal line by bonding between substrates by a seal line, the inner peripheral side seal line is formed of a sealant made of a foamed resin or a porous resin. Liquid crystal display device. 3. An inner peripheral side and an outer peripheral side double seal line are formed around an opposing surface of two substrates arranged facing each other, and a liquid crystal material and a spacer are arranged in the inner peripheral side seal line. A liquid crystal display device in which a substrate is joined by a seal line and a liquid crystal material is sealed in the seal line, wherein a cross-sectional shape of the inner peripheral side seal line is formed in a mountain shape.