JPH11337956A - Manufacture of liquid crystal display element and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve productivity by using a simple device. SOLUTION: A manufacturing method and its device is a method by which a photosetting material interposed between a pair of substrates 11A and 11B in which at least one of them is a transparent substrate is hardened by making light incident from the edge faces of transparent substrates 11A and 11B and by making the light well reach between both of the substrates 11A and 11B and thus, it is possible to rapidly harden the photosetting material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a photocurable material,
The present invention relates to a method and an apparatus for manufacturing a liquid crystal display element using a technique of interposing and curing between a pair of substrates, and more particularly to improvement of light irradiation on a photocurable material.

[0002]

2. Description of the Related Art Generally, in a process of assembling an empty cell before injecting liquid crystal into a liquid crystal display element, a sealing material is applied by printing or the like to one or both of a pair of substrates subjected to an alignment treatment, and an in-plane spacer is dispersed. Then, if necessary, the two substrates are fixed, and a pair of substrates are positioned, temporarily fixed and superposed, and pressed to fix both substrates. In this step, a photo-curing material is used as a sealing material for finally bonding the two substrates, a spacer fixing material for fixing the spacer between the two substrates, and a temporary fixing material for temporarily fixing the two substrates. Is done.

Examples of such a photocurable material include a resin mainly cured by ultraviolet rays, for example, a material mainly containing acrylic or methacrylic monomer, or a material made of a photoreactive epoxy resin.

By the way, in an empty cell assembling process before liquid crystal injection of a liquid crystal display element, for example, in a conventional apparatus using a photocurable material as a sealing material, as shown in FIG. Is a transparent substrate, a pair of substrates 1A and 1B are sandwiched between a pair of platens 2A and 2B made of a material capable of transmitting ultraviolet light such as quartz or borosilicate glass.
The light-curing resin applied between the two substrates 1A, 1B is cured by irradiating the light-curing resin with light from a lamp 3 in which a reflecting mirror 4 is located on the upper back of the upper platen 2A.
1B was to be bonded.

[0005]

However, the platens 2A and 2B made of quartz or the like need to have a size suitable for the transparent substrates 1A and 1B and a wall thickness sufficient to withstand the pressing pressure. As a result, the manufacturing costs of the platens 2A and 2B are high, and the entire apparatus is expensive. Also,
Most of the light from the lamp 3 is not only attenuated while passing through the platen 2A and reaching the photocurable material, but also because the thickness of the photocurable material, which is the light absorbing layer, is usually as small as several μm. Since a phenomenon that light simply passes through occurs, in order to cure the photocurable material to a level at which the reliability is sufficient, it is necessary to irradiate the light from the lamp 3 for a long time, and energy consumption is large. However, there was a problem that productivity was poor.

For this reason, a method and apparatus for manufacturing a liquid crystal display element using a photocurable material as a sealing material before the liquid crystal is injected has not been widely adopted and has been used up to now.

An object of the present invention is to provide a method and an apparatus for manufacturing a liquid crystal display element which can overcome such problems of the conventional one and can improve the productivity with a simple apparatus.

[0008]

In order to overcome the above-mentioned problems, a method of manufacturing a liquid crystal display element according to the present invention according to claim 1 is characterized in that at least one of the transparent substrates is a transparent substrate at a stage before liquid crystal injection. The point is that light is incident from the end face of the transparent substrate to cure the photocurable material interposed between the substrates. In addition, by adopting such a configuration, the light can reach the photocurable material well and the photocurable material can be quickly cured.

According to a second aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, wherein the incident angle of light from the end face of the transparent substrate is 5 °.
The point is that it is 0 degrees or less. By employing such a configuration, light can reach the photocurable material particularly efficiently.

According to a third aspect of the present invention, there is provided an apparatus for manufacturing a liquid crystal display element, wherein a light irradiating means for making light incident from an end face of a transparent substrate toward a photocurable material interposed between the two substrates is provided. It is in the point provided. Then, by adopting such a configuration, it is possible to satisfactorily reach the light from the light irradiation unit to the photocurable material through the end surface of the transparent substrate, and to quickly cure the photocurable material. .

According to a fourth aspect of the present invention, there is provided an apparatus for manufacturing a liquid crystal display element according to the present invention, wherein the light irradiating means comprises a plurality of optical fibers connected so that light from a light source is incident from an end face of the transparent substrate substrate. It has a point. By adopting such a configuration, light can be simultaneously incident from a wide range of the end face of the transparent substrate by a plurality of optical fibers, and can be cured more quickly.

According to a fifth aspect of the present invention, there is provided a liquid crystal display device manufacturing apparatus according to the present invention, wherein each of the optical fibers has a variable angle relative to an end face of a transparent substrate. By adopting such a configuration, by adjusting the angle with respect to the end face of the transparent substrate in consideration of total reflection and the like, light can reach the photocurable material even better, and the photocurable property is improved. The material can be cured more quickly.

[0013]

FIG. 1 shows a principle embodiment of an apparatus for manufacturing a liquid crystal display element according to the present invention. In this embodiment, a pair of substrates for forming a liquid crystal display element is used. 11A and 11B. In the present invention, at least one of the pair of substrates 11A and 11B needs to be a transparent substrate for the incidence of light from the end face of the substrate, but in the present embodiment, for convenience, both substrates 11A and 11B are used. 11B is described as a transparent substrate.

Incidentally, the transparent substrates 11A, 11B
In order to cure the photo-curable material by entering light from the end face of the transparent substrate 11A, 11
B, and the main wavelength 3 of the lamp 13 described later.
Need to agree.

For this reason, the transparent substrates 11A and 11B may be either ordinary glass substrates or plastic substrates. Among them, as the material of the glass substrate,
Soda lime, borosilicate glass, non-alkali glass and the like are used. As the material of the plastic substrate, polyethylene terephthalate, polycarbonate, or the like is used.

The pair of transparent substrates 11A and 11B are formed of a pair of platens 12A and
12B, the transparent substrates 11A, 1
A photocurable resin, which is a photocurable material, is applied in advance to the outer peripheral edge portion between 1B and in particular.

The photocurable resin contains, as a main component, a resin obtained by adding a photoinitiator and a sensitizer to an acrylic or methacrylic monomer and / or an oligomer which is mainly cured by ultraviolet rays. Incidentally, depending on the type of the photoinitiator and the sensitizer, a visible light curable type which is cured by visible light can also be used. In addition, a photoinitiator such as a type that generates an acid upon irradiation with light is also practical, and such a photoinitiator can be used.

A pair of lamps 13 serving as light irradiating means for irradiating light from an end face of the transparent substrate toward the photocurable resin interposed between the transparent substrates 11A and 11B is provided on both transparent substrates 11A and 11B. 11B are disposed so as to face both end surfaces 14A, 14B: 15A, 15B located on the back of each other. As the lamp 13, a high-pressure mercury lamp, a metal halide lamp, a xenon lamp, or the like can be used.

The wavelength for curing the photocurable resin by the lamp 13 needs to be in the high transmittance region of the transparent substrates 11A and 11B.
The glass substrate and the plastic substrate as A and 11B can transmit 365 nm which is the main wavelength of a high-pressure mercury lamp or a metal halide lamp at a very high rate. In addition, there is no problem because the glass substrate and the plastic substrate transmit the main wavelength of the xenon lamp well.

In this embodiment, the lamp 13
Is described from two directions of the transparent substrates 11A and 11B.
Irradiation may be performed from the four directions described above, or irradiation may be performed from only one direction.

Further, on the back of each lamp 13, most of the light from each lamp 13 is located on both sides 14A, 14B: 15A, which are located on the back of the transparent substrates 11A, 11B.
A reflecting mirror 16 on a spherical surface is provided to face the mirror 15B.

Further, the two transparent substrates 11A, 11
The incident angle of light from the end face of B is desirably 50 degrees or less in order to smooth the total reflection of light in the substrates 11A and 11B and reduce loss. For this reason, the position and direction of each lamp 13 and reflecting mirror 16 are made variable. In addition, both transparent substrates 11A, 11B
The positions and orientations of the platens 12A and 12B which hold the platen may be variable.

Next, the operation of the liquid crystal display device manufacturing apparatus according to the present embodiment having the above-described configuration, that is, the method of manufacturing the liquid crystal display device of the present invention will be described.

As shown in FIG. 1, a pair of platens 12A, 1
A photocurable material (not shown) is previously interposed between the pair of transparent substrates 11A and 11B sandwiched between 2B.

Therefore, both lamps 13 and both reflecting mirrors 16 are used.
To the end surface 14 of the transparent substrate 11A and / or 11B.
A, 14B: After positioning both lamps 13 at a predetermined position so that light is incident from 15A and 15B, and irradiating light of a wavelength that can cure the photocurable material used, The light travels while being totally reflected in the transparent substrates 11A and 11B, and is absorbed by the resin without being totally reflected only at a portion where a photocurable material having a refractive index larger than the refractive index of air is applied, and the light energy is highly efficient. Is used for curing the photocurable material. Then, total reflection is repeated in both the transparent substrates 11A and 11B until the light is attenuated,
Light energy is used effectively.

As a result, according to the present embodiment, the photocurable material can be efficiently cured.

As described above, according to the liquid crystal display device manufacturing apparatus of the present embodiment, productivity can be improved with a simple configuration.

FIGS. 2 and 3 show another embodiment of the apparatus for manufacturing a liquid crystal display element according to the present invention, which further embodies the light irradiation means in the embodiment of FIG. Therefore, the light irradiation means will be described with reference to FIGS.

The structure in which the reflecting mirror 16 is arranged on the back of the lamp 13 is the same as that in the embodiment of FIG. 1 described above, but in this embodiment, the transparent substrates 11A, 1
A plurality of optical fibers 18, 18... Are connected between the transparent substrates 11A, 11B and the lamp 13 so as to face almost the entire area of one end face 15A, 15B of 1B. Each optical fiber 18 has its proximal end connected to the lamp 13.
A condensing lens 19 that converges the light of the lamp 13 at the base end of each optical fiber 18 is disposed between the lamp 13 and the optical fiber 18. . Also, the rear end of each optical fiber 18 faces near the end surfaces 15A, 15B of any of the transparent substrates 11A, 11B. The tip of each optical fiber 18 is movable so that the incident angle of light on the transparent substrates 11A and 11B can be changed.

According to the substrate bonding apparatus using the light irradiation means having such a configuration, the light of the lamp 13 is efficiently transmitted to the end surfaces 15A, 15B of the transparent substrates 11A, 11B by the plurality of optical fibers 18. Thus, the photocurable material can be more efficiently cured.

Next, specific examples of a method and an apparatus for manufacturing a liquid crystal display element according to the present invention will be described.

[0032]

EXAMPLE 1 A transparent substrate made of soda lime (300 mm × 260 mm,
After forming a silica film and an ITO film to a thickness of 0.7 mm by sputtering, patterning was performed by photolithography to form a transparent electrode. Next, the middle coat and the polyimide alignment film were sequentially printed and fired. Subsequently, UR-8 is used as a UV-curable sealant.
000 (manufactured by Chise Nagase), superimposed and temporarily fixed, and sandwiched by a crimping machine with optical fiber. The light from the high-pressure mercury lamp was condensed on the end face of the transparent substrate while the pressure of both pressure plates of the crimping machine was 0.5 kg / cm ² , and the integrated light quantity was measured at the outlet at the tip of the optical fiber, and the integrated light quantity was 1000 mJ / cm ^2.
About 1/8 of the conventional method.

After the assembled substrate was cut into panels, liquid crystal was injected by a vacuum injection method and heated at 110 ° C. for 30 minutes.

When a reliability test was performed after attaching the polarizing plate, it was found to be 50% under high temperature and high humidity conditions of 60 ° C. and 90% RH.
No display failure mode was found after 0 hours.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made as necessary.

[0036]

As described above, according to the method and apparatus for manufacturing a liquid crystal display device of the present invention, the productivity can be improved with a simple apparatus.

That is, according to the method of manufacturing a liquid crystal display device of the present invention, a photocurable material interposed between a pair of substrates, at least one of which is a transparent substrate, is irradiated with light from an end face of the transparent substrate. To cure the photocurable material, the light can reach the photocurable material satisfactorily, the photocurable material can be rapidly cured, which can contribute to energy saving and improve productivity. .

According to the method for manufacturing a liquid crystal display element of the present invention according to the second aspect, since the incident angle of light from the end face of the transparent substrate is 50 degrees or less, the light can reach the photocurable material particularly efficiently. Row energy loss can be kept low. .

According to a third aspect of the present invention, there is provided an apparatus for manufacturing a liquid crystal display element according to the present invention, wherein a light irradiating means for making light incident from an end face of a transparent substrate toward a photocurable material interposed between the two substrates is provided. Therefore, the light can be satisfactorily reached from the light irradiating means to the photocurable material through the end face of the transparent substrate, and the photocurable material can be rapidly cured, which can contribute to energy saving. The productivity is also improved, and it is not necessary to use an expensive ultraviolet-transparent platen, an inexpensive metal platen can be used, and the apparatus can be manufactured at low cost.

According to a fourth aspect of the present invention, there is provided an apparatus for manufacturing a liquid crystal display element according to the present invention, wherein the light irradiating means has a plurality of optical fibers connected so that light from a light source is incident from an end face of the transparent substrate. Therefore, light can be simultaneously incident from a wide range of the end face of the transparent substrate by a plurality of optical fibers, and can be cured more quickly.

According to a fifth aspect of the present invention, since each optical fiber has a variable angle relative to the end face of the transparent substrate, the optical fiber is transparent in consideration of total reflection and the like. By adjusting the angle to the end face of the board,
The light can reach the photocurable material more favorably, and the photocurable material can be cured more quickly, and the energy loss can be reduced.

[Brief description of the drawings]

FIG. 1 shows a first example of a liquid crystal display device manufacturing apparatus according to the present invention.
Schematic configuration diagram showing an embodiment

FIG. 2 shows a second embodiment of the liquid crystal display device manufacturing apparatus according to the present invention.
Front view showing an embodiment

FIG. 3 is a plan view of FIG. 2;

FIG. 4 is a schematic configuration diagram showing a conventional liquid crystal display element manufacturing apparatus.

[Explanation of symbols]

 1A, 11B Transparent substrate 12A, 12B Platen 13 Lamp 14A, 14B, 15A, 15B End face 16 Reflector 18 Optical fiber

Claims (5)

[Claims] 1. A method for manufacturing a liquid crystal display element, comprising: a step of curing a photocurable material interposed between a pair of substrates, at least one of which is a transparent substrate, before injecting liquid crystal. A method for manufacturing a liquid crystal display element, comprising curing a transparent material by irradiating light from an end face of a transparent substrate. 2. The method according to claim 1, wherein an incident angle of light from an end face of the transparent substrate is 50 degrees or less. 3. A manufacturing apparatus for a liquid crystal display element having a light irradiation means for curing a photocurable material interposed between a pair of substrates at least one of which is a transparent substrate at a stage before liquid crystal injection. The apparatus for manufacturing a liquid crystal display element, wherein the light irradiation means is provided so that light is incident on the photocurable material from an end face of the transparent substrate. 4. The light irradiating means has a plurality of optical fibers connected so that light from a light source is incident from an end face of a transparent substrate.
3. A manufacturing apparatus for a liquid crystal display element according to claim 1. 5. The apparatus according to claim 4, wherein each of the optical fibers has a variable angle relative to an end face of the transparent substrate.