JPH05281556A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To provide a liquid crystal display element capable of preventing the color unevenness of cells generated by gap unevenness by preventing the movement of gap material from an electrode part to an insulating part so as to attain the uniformity of cell gaps. CONSTITUTION:Gap material 4 is rigidly fixed to at least one of oriented bases at least one of which is formed of a plastic film base, then sealant 3 is formed at the periphery, and a liquid crystal is interposed inside to form a liquid crystal display element. In this liquid crystal display element, the gap material 4 is formed in the plurally connected state (5).

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,
Specifically, it can be applied to PF-LCDs, etc.
The present invention relates to a liquid crystal display element capable of preventing the movement of a gap material and making the cell gap uniform.

[0002]

2. Description of the Related Art A conventional liquid crystal display device is disclosed in, for example, Japanese Patent Laid-Open No. 60-21027, in which two synthetic resin films each having a transparent electrode formed on one surface thereof are hot. It is configured to be fixed via spacer powder coated with a melt adhesive, and a highly reliable liquid crystal display device is obtained.

Further, for example, in the liquid crystal display element reported in Japanese Patent Laid-Open No. 61-67830, a spacer made of an organic insulating material is used between a pair of plastic substrates, the diameter of which is smaller than the gap between the substrates, and a specific number of spacers are used. Is uniformly dispersed and fixed in the alignment film, and the separation, movement, and aggregation are prevented to improve reliability. Further, for example, in the liquid crystal display element reported in Japanese Patent Laid-Open No. 62-73232, a thermal non-plastic spacer for forming a cell gap between both alignment films, and a vertical alignment film for bonding a vertical alignment film formed larger than the thermal non-plastic spacer And the thermoplastic spacer, the cell gap is properly secured, and at the same time, the fixing strength of the glass substrate is improved.

By the way, in the conventional liquid crystal display device,
In the gap material, for example, divinylbenzene and styrene
Spherical spherical plastic beads such as copolymers, SiO₂，
Al ₂O₃Spherical metal oxides such as glass fiber
Is used. Of these liquid crystal display elements, plastic
Liquid crystal display device (hereinafter referred to as PF-LCD)
In S.), since the ITO electrode has low scratch resistance,
The electrode is easily damaged at the end of the fiber and can be used.
I can't come. For this reason, plastic beads and metal oxide
Is used.

[0005]

However, if the above-mentioned simple substance of beads is used for a liquid crystal display device, the structure shown in FIG.
As shown in, after the liquid crystal is injected, the gap material 31 is the IT on the common side.
A large number of the gap materials 31 on the common side ITO electrode 33 are extremely reduced by moving from the O electrode 33 to the insulating part 32, and the number of the gap materials 31 is extremely reduced, resulting in nonuniform cell gap and STN cell color spotting. There was a problem that it would end up. In FIG. 4, 34 is a peripheral sealant.

Therefore, as a conventional technique for solving the problem that a large number of the gap members 31 move to the insulating portion 32 and concentrate, a method of using a fixed type gap member has been proposed and has already been put into practical use. ing. As described above, various methods have been proposed for fixing the gap material, but the mainstream is to form an adhesive thermoplastic resin or thermosetting resin on the outer periphery of the gap material, and heat the alignment film surface. It is configured to be fixed to.

By the way, the inventors of the present invention have made various studies as to the fixing gap material for PF-LCD, and found that the acrylic material is the best. On the other hand, the olephone-based material and the epoxide-based material have the advantage that they have a strong adhesiveness, but they also have a strong cohesiveness, so that uniform spraying has become difficult. When the above-mentioned acrylic material is used, the adhesiveness is weaker than other materials, but since the dispersibility is good, it is possible to uniformly disperse and a uniform cell gap can be achieved.

However, as described above, since the fixing force is insufficient, movement occurs in a partial area in the cell (which occurs around the viewing area in the cell for moving the gap material), and the electrode portion is moved. The gap material particles scattered on the electrode moved to the insulating portion, and the electrode portion became sparse and the insulating portion became dense. In particular, in the PF-LCD, since the substrate is flexible, the cells are easily stressed, and the gap material is very easy to move as compared with the glass panel.

Therefore, according to the present invention, the gap material can be prevented from moving from the electrode portion to the insulating portion to make the cell gap uniform, and the cell color unevenness caused by the gap unevenness can be prevented. It is intended to provide a liquid crystal display device.

[0010]

The invention according to claim 1 is
At least one is made of plastic film substrate,
In a liquid crystal display element in which a gap material is fixed to at least one of the substrates that have been subjected to the alignment treatment, a sealing material is formed in the periphery, and a liquid crystal is interposed inside, a plurality of the gap materials are connected. To do.

The invention according to claim 2 is characterized in that the number of the connecting gap members is 5 or more and 100 or less. The invention according to claim 3 is characterized in that the connection gap member is connected across the electrode portion and the insulating portion. The invention according to claim 4 is characterized in that the connection gap member extends in a branch shape and intersects with each other.

The invention according to claim 5 is characterized in that the connecting gap material is at least one of true spherical particles and rod-shaped fibers. In the invention according to claim 6, the abundance density of the monodisperse gap material particles is
It is characterized in that it is 100 pieces / mm ² or more and 300 pieces / mm ² or less, and the existence density of the connecting gap material group is 1 place / mm ² or more and 5 places / mm ² or less.

[0013]

Conventionally, for example, in a PF-LCD, since the substrate is flexible, the gap material easily moves even after the panel is formed, and after the liquid crystal is injected, the liquid crystal is extruded excessively, or the polarizing plate is attached to the panel. The gap material was very easy to move due to the process cell which is directly stressed.

On the other hand, according to the first aspect of the present invention, since the gap members are connected to each other, both in the panel process and after the unit process,
The gap material can be prevented from moving from the electrode portion to the insulating portion, and the gap material can be uniformly dispersed in the cell. Therefore, the cell gap can be made uniform, and color spots caused by gap spots can be prevented.

In the second aspect of the present invention, the preferable number of the connecting gap members is 5 or more and 100 or less. When the number is less than 5, the connecting gap members are too small and the gap members move, resulting in a cell gap. Uniformity is difficult to measure, which is not preferable, and when the number is more than 100, the number of connecting gap members is too large and three-dimensional arrangement is likely to occur to cause defects, which is not preferable because the cell contrast is lowered. For this reason,
When the number is 5 or more and 100 or less, the preferable number of the connecting gap materials is defined, so that the movement of the gap materials can be efficiently prevented, and the liquid crystal display element with high gap accuracy without point defect defects due to aggregation can be efficiently provided. Obtainable.

According to the third aspect of the invention, the installation position of the connection gap member is preferably defined so that the connection gap member is continuous over the electrode portion and the insulating portion. In addition, it is possible to efficiently eliminate the movement of the gap material, and it is possible to efficiently obtain a cell having a uniform gap in the panel. In the invention according to claim 4, since the connecting gap member is configured to extend in a branch shape and intersect with each other, the effect of preventing movement of the gap member can be further improved. Therefore, it is possible to prevent the occurrence of gap variation not only during the process but also in various tests (for example, 40 ° C., 90% energization test, 60 ° C., 90% leaving test, and dot test).

According to the fifth aspect of the present invention, since the connecting gap material is appropriately specified so that the connecting gap material is at least one of true spherical particles and rod-shaped fibers, the connecting gap material is determined according to the material model to be used. Materials and combinations can be selected appropriately. Therefore, it is advantageous in terms of productivity and cost. In the invention according to claim 6, the existence density of the monodisperse gap material particles is 100 particles / mm ² or more and 300 or more.
Since the distribution density of the monodisperse gap material particles and the connection gap material group is preferably specified so that the existence density of the connection gap material group is 1 piece / mm ² or less and the existence density of the connection gap material group is 1 place / mm ² or more and 5 places / mm ² or less. In addition, it is possible to increase the accuracy of the in-panel gap, and to minimize the fine color spots in the panel.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a sectional view showing the structure of a liquid crystal display device according to Embodiment 1 of the present invention. In FIG. 1, 1 is an ITO electrode on the common side, 2 is an insulating portion, and 3 is a peripheral sealing material that seals the peripheral portion. Further, 4 is a gap material particle such as plastic beads, and 5 is a connection gap material formed by connecting a plurality of gap material particles 4.

In the present embodiment, a plurality of gap material particles 4 are arranged in one direction (the number of particles of the connected population is preferably 5 or more and 100 or less as described above), and the common side ITO electrode 1 and the insulating portion 2 are arranged. The connection gap member 5 is formed by being connected to each other. At this time, each particle is adhered and fixed to the substrate (alignment film surface) and the adjacent gap particle. As described above, in this embodiment, since the connecting gap material 5 is configured so that the plurality of gap material particles 4 are connected in the cell, the gap material particles 4 are formed during the paneling process and after the unitization. It is possible to prevent movement from the common side ITO electrode portion 1 to the insulating portion 2, and it is possible to uniformly disperse the gap material particles 4 in the cell. Therefore, the cell gap can be made uniform, and color spots caused by gap spots can be prevented.

Further, the connecting gap member 5 is made of ITO on the common side.
Since the installation position of the connection gap material 5 is preferably defined so as to be continuous over the electrode portion 1 and the insulating portion 2, the movement of the gap material particles 4 seen in the peripheral portion of the viewing area can be efficiently eliminated. Therefore, it is possible to efficiently obtain a cell having a uniform in-panel gap. (Embodiment 2) FIG. 2 is a sectional view showing the structure of a liquid crystal display element according to Embodiment 2 of the present invention. In FIG. 2, FIG.
The same reference numerals denote the same or corresponding parts.

In this embodiment, the effect of the first embodiment can be obtained and, in addition, since the connecting gap material 5 is formed so as to extend and intersect in a branch shape, the effect of preventing the movement of the gap material particles 4 is further improved. Can be improved. For this reason, not only during the process but also for various tests (eg 40 ° C, 90%
It is also possible to prevent gap fluctuations in the energization test, 60 ° C 10% leaving test, and dot test). (Embodiment 3) FIG. 3 is a sectional view showing the structure of a liquid crystal display element according to Embodiment 3 of the present invention. In FIG. 3, FIG.
The same reference numerals as 2 indicate the same or corresponding parts.

In this embodiment, the same effect as in Embodiments 1 and 2 can be obtained, and in addition, the connecting gap material 5 is configured such that spherical beads and rod-shaped fibers are mixed and connected, and the connecting gap material is formed. Since the five materials are specified as appropriate, it is possible to appropriately select the materials and combinations according to the material model to be used. Therefore, it is advantageous in terms of productivity and cost.

The spherical beads may be plastic beads, metal oxide beads, etc., and the rod-shaped fibers may be glass fibers, plastic fibers, etc. However, when glass fibers are used, electrode damage may occur. It is preferable to use plastic fibers because of their properties. In addition, although the case where the beads and the fibers are mixed and continuous with each other has been described in the third embodiment, the present invention is not limited to this and, for example, even when only the beads are continuous. It does not matter if the fibers are scattered or vice versa.

[0024]

According to the present invention, it is possible to prevent the gap material from moving from the electrode portion to the insulating portion to make the cell gap uniform, and to prevent the cell color unevenness caused by the gap unevenness. There is an effect that can be.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a structure of a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a structure of a liquid crystal display element according to a second embodiment of the present invention.

FIG. 3 is a sectional view showing a structure of a liquid crystal display element according to a third embodiment of the present invention.

FIG. 4 is a cross-sectional view showing the structure of a liquid crystal display element for explaining the problems of the conventional example.

[Explanation of symbols]

 1 ITO electrode on the common side 2 Insulation part 3 Peripheral sealing material 4 Gap material particles 5 Connection gap material

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hiroshi Ikeguchi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd.

Claims (6)

[Claims] 1. A liquid crystal display device comprising at least one plastic film substrate, a gap material fixed to at least one of the substrates subjected to an orientation treatment, a sealing material formed around the substrate, and a liquid crystal interposed therein. A liquid crystal display device comprising a plurality of the gap members connected to each other. 2. The number of the connection gap members is 5 or more and 100 or more.
The liquid crystal display device according to claim 1, wherein the number is less than or equal to 2. 3. The connection gap material is formed by connecting the electrode portion and the insulating portion over the electrode portion and the insulating portion.
The liquid crystal display element described. 4. The liquid crystal display device according to claim 1, wherein the connection gap member extends in a branch shape and intersects with each other. 5. The liquid crystal display device according to claim 1, wherein the connection gap material is at least one of true spherical particles and rod-shaped fibers. 6. the density of monodisperse gap material particles is 100 or / mm ² to 300 pieces / mm ² or less, and the density of the connecting gap material population 1 point / mm ² or more 5 points / m
The liquid crystal display device according to claim 1, wherein the liquid crystal display device has a size of m ² or less.