JP2012053364A - Liquid crystal display element and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display element which achieves high mass productivity and can sufficiently block light in a display region with a degree of lamination accuracy of existing equipment.SOLUTION: A first electrode substrate 2 having a display region 1 and a second electrode substrate 4 having a first light blocking region 3 in a positional relation opposing to the first electrode substrate 2 are laminated through a sealant 5 spaced at a predetermined distance. A portion of the sealant 5 which is not covered with the first light blocking region 3 is covered with a second light blocking region 7 with which a third substrate 6 is provided, so that the light is blocked over an entire region of the sealant 5 with the first light blocking region 3 and the second light blocking region 7. The sealant 5 is made of an X-ray curable resin. Since a portion of the sealant 5 adjacent to the display region 1 from which the light is blocked has a width equal to or less than 1/3 that of the sealant 5, the remaining 2/3 or more region can be exposed to UV (ultraviolet ray) radiation. An existing X-ray curable resin can thus be used as the sealant 5.

Description

  The present invention relates to a liquid crystal display element and a method for manufacturing the same.

  In general, a liquid crystal display element has a first electrode substrate having a pixel electrode formed on a surface thereof and a second electrode substrate having a counter electrode formed on the surface opposite thereto and bonded with a sealant in a predetermined positional relationship, A liquid crystal panel in which liquid crystal is injected between substrates is mounted on a circuit board or a base, a potential difference is applied between a pixel electrode and a counter electrode, and various displays are obtained by controlling the alignment of the liquid crystal.

  In the liquid crystal display element, a pixel electrode is formed in the display area, and a pattern similar to the pixel electrode is formed as a dummy area on the outer periphery of the display area. The dummy area has a pixel electrode pattern similar to that of the display area, but unlike the pixel electrode of the display area, each pixel electrode is not electrically independent. That is, the entire dummy area is one electrode.

  In addition to the dummy area, the second electrode substrate is generally provided with a frame light shielding area that defines a frame of the display area in the liquid crystal element. In order to cure the sealing agent, the light shielding region is often formed with a gap so as not to overlap the sealing agent region so as not to prevent ultraviolet irradiation from the outside of the second electrode substrate. . For this reason, there is a possibility that the light shielding quality may be deteriorated due to light leaking from the gap between the light shielding region and the seal region.

FIG. 4 is a cross-sectional view showing a conventional liquid crystal display element.
In order to prevent the light leakage described above, the first light shielding region 3 on the second electrode substrate 4 and the third substrate 6 having the second light shielding region 7 on the second electrode substrate 4 are bonded together. Further, a third light shielding region 8 is provided in the lower part of the first electrode substrate 2 in consideration of a shift of an overlapping portion between the first light shielding region 3 and the second light shielding region 7. In addition, a configuration in which the outer peripheral portion of the sealant 5 is shielded by the mounting case 9 is disclosed. (For example, see Patent Document 1)

  Since the liquid crystal display element shown in FIG. 4 uses an ultraviolet curable resin as the sealant 5, it is necessary to perform UV irradiation for curing. Light shielding of the contact surface of the sealing agent 5 with the liquid crystal 10 is performed in the second light shielding region 7 provided on the third substrate 6, but when the distance between the sealing agent 5 and the display region 1 is small, The bonding accuracy between the third substrate 6 having the second light shielding region 7 and the first electrode substrate 2 having the display region 1 becomes strict, and the gap between the second light shielding region 7 and the display region 1 is Since the second electrode substrate 4 is interposed, it is necessary to consider the incident light angle dependency corresponding to the thickness of the second electrode substrate 4.

Japanese Patent Application No. 2006-157016

  In the structure of the conventional liquid crystal cover element shown in FIG. 4, the sealant 5 and the display region 1 are close to each other because the sealant 5 is shielded from light on the display region 1 side by the second light shield region 7. In this case, the bonding accuracy is very important and is not suitable for mass production. If the bonding accuracy is taken into consideration, the first light shielding region 3 cannot have a sufficient light shielding width.

  FIG. 5 is a diagram showing a part of the structure of FIG. 4 when the sealant 5 and the display area 1 are adjacent to each other. The distance between the sealant 5 and the display area 1 is, for example, 300 μm. The frame light-shielding area that defines the frame on the display area 1 side of the sealant 5 has an interval of 300 μm and, for example, 100 μm is inserted from the sealant 5 to the display area side in order to ensure light-shielding properties. It is out.

In the above state, if the incident light has an incident light angle of 10 ° from the normal direction, the incident light having the angle from the second light shielding region 7 to the display region on the first electrode substrate 2 is assumed. 1, assuming that the thickness of the second electrode substrate 4 is 0.5 mm, tan (10 °) × 0.5 mm = 88.2 μm
As described above, at least 88 μm enters the inside from the end face of the second light shielding region 7. Further, as shown in FIG. 5, since only 200 μm is provided from the end face of the second light shielding area 7 to the end face of the display area 1, the third substrate 6 having the second light shielding area 7 and the display area The bonding accuracy with the first electrode substrate having 1 needs to be carried out within ± 50 μm.

  As a process of bonding the second electrode substrate 4 with an accuracy of ± 50 um, performing the third substrate 6 on the first electrode substrate 2 and the second electrode substrate 4 that have already been bonded together is a mass production process. Is very inappropriate, and it is general that the bonding margin is larger.

  The above-mentioned contents are all applicable to a small liquid crystal display element in which the distance between the sealant 5 and the display area 1 is 300 μm or less.

  The present invention provides a liquid crystal display that is excellent in mass productivity and sufficiently shields the display area by the bonding accuracy of existing equipment, even in a small liquid crystal display element in which a sealant area and a display area are adjacent to each other. An element is to be provided.

  In the liquid crystal display element of the present invention, a first electrode substrate having a plurality of pixel electrodes and a second electrode substrate having a counter electrode opposite to the first electrode substrate are bonded to each other at a predetermined interval via a sealant. In the liquid crystal display element in which the liquid crystal is sealed at the predetermined interval and the sealing agent and the plurality of pixel electrodes are adjacent to each other, the second electrode substrate has the first electrode on the second electrode substrate. A first light-shielding region that defines the periphery of a plurality of pixel electrode regions on one electrode substrate and covers four sides of the sealant on the pixel electrode side; and the first of the sealant A third substrate provided with a second light-shielding region that shields light from a portion not covered by the light-shielding region is provided on the second electrode substrate.

  The third substrate having the second light shielding region can also be configured to serve as a retardation plate.

  A step of bonding a first electrode substrate having a plurality of pixel electrodes and a second electrode substrate having a first light-shielding region through a sealant in a predetermined positional relationship; and not covered by the first light-shielding region And a step of bonding a third substrate having a second light shielding region on the second electrode substrate in order to cover the sealant portion.

  According to the present invention, in a small liquid crystal display element in which a sealant region and a display region are adjacent to each other, it is possible to provide a frame light-shielding region that is excellent in mass productivity and that performs a frame of the display region with the bonding accuracy of existing equipment. It is.

Sectional drawing which shows one Example of the liquid crystal display element of this invention. Sectional drawing for every process which shows the manufacturing method of the liquid crystal ideographic element of this invention. Sectional drawing which shows another Example of the liquid crystal display element of this invention. Sectional drawing which shows the liquid crystal display element of a prior art. Partial sectional view showing a state in which incident light having an angle is irradiated to the prior art structure

FIG. 1 is a cross-sectional view showing an embodiment of the liquid crystal display element of the present invention.
A first electrode substrate 2 having a display region 1 and a second electrode substrate 4 having a first light-shielding region 3 in a positional relationship facing the first electrode substrate 2 are bonded to each other at a predetermined interval via a sealant 5. Has been.

  Further, regarding the portion of the sealant 5 that is not covered by the first light-shielding region 3, the second light-shielding region 7 provided on the third substrate 6 covers the whole area of the sealant 5 and the first light-shielding region 3 and In the second light shielding region 7, light shielding is performed. The sealing agent 5 is an ultraviolet curable resin.

  In the structure of the liquid crystal display element shown in FIG. 1, light shielding on the display region 1 side of the sealant 5 is performed by the first light shielding region 3, and the alignment accuracy is the same as that of the first electrode substrate 2 and the second electrode. It depends on the bonding accuracy of the electrode substrate 4.

  In the structure of the liquid crystal display element shown in FIG. 1, the portion of the sealant 5 that shields light on the display region 1 side is 1/3 or less of the width of the sealant 5 and the remaining 2/3 or more. Since UV (ultraviolet) irradiation can be performed on the region, it is possible to use an existing ultraviolet curable resin for the sealant 5.

FIG. 2 is a diagram showing a method for manufacturing the liquid crystal display element of FIG. Hereinafter, description will be made according to the cross-sectional view for each step in FIG.
(A): The first electrode substrate 2 having the display region 1 and the second electrode substrate 4 having the first light-shielding region 3 are bonded to each other at a predetermined interval via the sealant 5. In general, the bonding accuracy can be ± 50 μm. Further, the display area 1 side portion of the sealant 5 is shielded from light by the first light shielding area 3. The sealing agent 5 is cured by UV irradiation, for example.

  (B): A second light-shielding region 7 was provided on the second electrode substrate 4 of the first electrode substrate 2 and the second electrode substrate 4 bonded together at a predetermined interval with the sealant 5. The third substrate 6 is bonded with, for example, an optical UV curable resin. The second light shielding area 7 is for the purpose of light shielding the portion of the sealant 5 that is not covered by the first light shielding area 3, and the frame light shielding of the display area 1 is performed in the first light shielding area 3. Therefore, the bonding accuracy at this time is not particularly limited.

  According to the manufacturing method described above, in the manufacturing process of the small liquid crystal display element in which the sealant region and the display region are adjacent to each other, the frame light shielding region on the display region side of the sealant is provided on the second electrode substrate as the first light shielding region. Accordingly, mass production of liquid crystal display elements capable of sufficiently shielding the display area with existing materials and process accuracy can be performed.

FIG. 3 is a sectional view showing another embodiment of the liquid crystal display element of the present invention.
A first electrode substrate 2 having a display region 1 and a second electrode substrate 4 having a first light-shielding region 3 in a positional relationship facing the first electrode substrate 2 are bonded to each other at a predetermined interval via a sealant 5. Has been. Further, the sealant 5 part not covered by the first light-shielding region 3 is covered by the second light-shielding region 7 provided in the third substrate 6, so that the entire sealant 5 is covered with the first light-shielding region 3, and Light shielding is performed in the second light shielding region 7. Note that the third substrate 6 can also include a retardation plate 11 and can adjust the optical characteristics of the liquid crystal display element at the same time.

  The transmittance of the light shielding region 3 is preferably OD (Optical Density) of 3 or more, but is not limited thereto.

DESCRIPTION OF SYMBOLS 1 Display area 2 1st electrode board 3 1st light shielding area 4 2nd electrode board 5 Sealant 6 3rd board | substrate 7 2nd light shielding area 8 3rd light shielding area 9 Mounting case 10 Liquid crystal 11 Phase difference plate

Claims (3)

After a first electrode substrate having a plurality of pixel electrodes and a second electrode substrate having a counter electrode opposite to the first electrode substrate are bonded to each other through a sealant at a predetermined interval, liquid crystal is applied at the predetermined interval. In the liquid crystal display element formed by sealing, and the sealing agent and the plurality of pixel electrodes are adjacent to each other,
A first electrode is formed on the second electrode substrate so as to define a periphery of the plurality of pixel electrode regions on the first electrode substrate and to cover four sides of the sealant on the plurality of pixel electrodes side. A light shielding area;
A liquid crystal display element, wherein a third substrate having a second light-shielding region that shields a portion of the sealant that is not covered by the first light-shielding region is provided on the second electrode substrate.   The liquid crystal display element according to claim 1, wherein the third substrate having the second light shielding region also serves as a retardation plate. Bonding a first electrode substrate having a plurality of pixel electrodes and a second electrode substrate having a first light-shielding region through a sealant in a predetermined positional relationship;
A method of manufacturing a liquid surface display element, comprising: a step of bonding a third substrate having a second light-shielding region to cover the sealant portion, which is not covered by the first light-shielding region, on the second electrode substrate. .

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