JPH09258233A - Liquid crystal display element and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a display element having high display grade which is formed to obviate the degradation in yield due to color unevenness and the fluctuation in the gap between upper and lower substrates by external stress after completion by adhering spacer to the upper and lower substrates with a UV-curing adhesive. SOLUTION: Prescribed patterns are formed by a photolithography method on glass with ITO. An oriented film 3 is formed by offset printing thereon and is baked. After the oriented film 3 is subjected to the orientation treatment by rubbing the oriented film in a prescribed direction with cloth, the surface of the one substrate is printed with a material formed by kneading the spacers 4 of the prescribed size into the UV curing resin by a metal screen mask. The spacers 4 in the liquid crystal display element and the seals 5 for adhering the upper and lower substrates 1 are simultaneously formed. The substrate is stuck to another substrate and while a uniform pressure is applied thereon, the substrates are irradiated with UV rays, by which the UV curing resin is cured.

Description

Detailed Description of the Invention

[0001]

[0001] The present invention relates to a liquid crystal display device. Particularly, color spots and local color tone changes (hereinafter referred to as color unevenness)
The present invention relates to a liquid crystal display element having a high display quality, which is capable of improving the display characteristics by preventing the occurrence of color irregularity and causing less color unevenness even when external stress is applied. It also relates to electronic devices.

[0002]

2. Description of the Related Art Conventionally, spacers used to maintain a gap between upper and lower substrates are scattered on one substrate before the upper and lower substrates are adhered, and the other spacer is attached to a substrate coated with a seal for adhering the upper and lower substrates. Liquid crystal display device using flexible substrate such as plastic film by heating after combining and heat curing seal is sprayed on one substrate with the spacer coated with thermoplastic resin and the other seal The resin was melted by bonding and heating the substrate coated with and the temperature was returned to room temperature to solidify the resin, and the intermolecular force at that time adhered the spacer to the upper and lower film substrates.

[0003]

However, the spacers just scattered between the upper and lower substrates are not fixed, and the spacers move due to the movement of the liquid crystal when the liquid crystal is filled, which causes color unevenness. It was a factor that caused it.

Further, in the case of a liquid crystal display device using a flexible substrate such as a plastic film, the adhesive force is not sufficient only by adhering the upper and lower film substrates by the intermolecular force of the thermoplastic resin. Adhesion of the upper and lower film substrates may be peeled off by the force that widens the upper and lower film substrates, or the spacers may move due to external stress after being mounted on the electronic device, or the upper and lower film substrates may be peeled off. As a result, color unevenness occurs and the display quality is degraded.

Therefore, the present invention solves such a problem, and its purpose is to prevent the movement of the spacer and the gap between the upper and lower substrates from becoming wider than a predetermined gap by adhering the spacer to the upper and lower substrates with a UV curing resin. By doing so, it is an object of the present invention to provide a liquid crystal display device having high display quality and an electronic device equipped with the liquid crystal display device, in which the yield due to color unevenness is not reduced and the gap between the upper and lower substrates is not changed by external stress after completion.

[0006]

According to another aspect of the present invention, in a liquid crystal display element, liquid crystal is sandwiched between a pair of upper and lower substrates with a transparent electrode and an alignment film formed on the inner surfaces of the substrates through a spacer. In the liquid crystal display device described above, the spacers are bonded to the upper and lower substrates with a UV curable resin.

According to a second aspect of the present invention, in the liquid crystal display element according to the first aspect, the upper and lower substrates are plastic films.

A liquid crystal display element according to a third aspect is the liquid crystal display element according to the first aspect, wherein the UV curable resin is formed at the same time as a seal for bonding the upper and lower substrates.

A liquid crystal display element according to a fourth aspect is the liquid crystal display element according to the third aspect, characterized in that the seal is made of a UV curable resin. According to a fifth aspect of the present invention, there is provided an electronic apparatus including the liquid crystal display element according to any of the first to fourth aspects.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

[Embodiment 1] FIG. 1 is a sectional view of a liquid crystal display device of this embodiment. Here, 1 is an upper glass substrate and a lower glass substrate, both of which are glass plates having a thickness of 0.4 mm. 2 is IT
Transparent electrode consisting of O (indium tin oxide) film, 3
Is an alignment film, 4 is a spacer, 5 is a frame seal, 10 is a liquid crystal, and 6 is a UV curable resin.

In the method of manufacturing the present liquid crystal display element, a glass having ITO is formed into a predetermined pattern by a photolithography method. An alignment film 3 is formed thereon by offset printing and baked to form a film. Next, the alignment film 3
After rubbing with a cloth in a predetermined direction for alignment treatment, a material in which a spacer of a predetermined size is kneaded into a UV curable resin is printed on one of the substrates with a metal screen mask shown in FIG. At the same time, a seal for adhering the spacer and the upper and lower substrates is formed, the seal is attached to the other substrate, and UV light is irradiated while applying uniform pressure to cure the UV curable resin. Spacer print density is 50 pcs / m
A metal screen mask was prepared so as to have a size of m ² .
Thickness of the concrete metal screen mask is 1
The diameter of the hole is 20 in the spacer part on the stainless steel plate of 5 μm.
The holes were formed to have a size of μm, and the frame seal part was formed by arranging holes having a diameter of 20 μm at intervals of 20 μm. This time, the photolithography method was used to open the holes. Next, the liquid crystal 10 was filled by a vacuum injection method, and the injection part was sealed with an epoxy adhesive. Polarizing plates were attached to the top and bottom of this liquid crystal cell to complete a liquid crystal display device. At the same time, a comparative liquid crystal display device as shown in FIG. 5 was manufactured. As a method for manufacturing a comparative liquid crystal display element, a glass having ITO is formed into a predetermined pattern by a photolithography method. An alignment film 3 is formed thereon by offset printing and baked to form a film. Next, the alignment film 3 is rubbed with a cloth in a predetermined direction to carry out an alignment treatment, and then a thermosetting epoxy adhesive having a predetermined gap material as a sealing material is screen-printed on one of the substrates to obtain a substrate. A spacer is sprayed onto the substrate by a wet spray method, and the two substrates are stuck together and heated at 150 ° C. while applying a uniform pressure to cure the thermosetting epoxy adhesive to bond the upper and lower substrates. . The dispersion density of the spacers was 50 co / mm ² . Next, the liquid crystal 10 was filled by a vacuum injection method, and the injection part was sealed with an epoxy adhesive. Polarizing plates were attached to the top and bottom of this liquid crystal cell to complete a liquid crystal display device.

When the appearance of the liquid crystal display element thus manufactured was observed, color unevenness was not observed in the liquid crystal display element of the present invention. As a result, the color tone became narrow and color unevenness was locally generated, and the overall color tone was changed due to excessive filling of liquid crystal.

[Embodiment 2] FIG. 1 shows a sectional view of a liquid crystal display element of the present embodiment. Here, 1 is an upper film substrate and a lower film substrate, both of which were made of PET (polyethylene terephthalate) film having a thickness of 100 μm. 2 is a transparent electrode made of an ITO (indium tin oxide) film, 3 is an alignment film, 4 is a spacer, 5 is a frame seal, 10
Is a liquid crystal, and 6 is a UV curable resin.

In the method of manufacturing the present liquid crystal display element, the transparent electrode 3 is formed on the PET film by the low temperature sputtering method, and a predetermined pattern is formed by the photolithography method. An alignment film 3 is formed thereon by offset printing and baked to form a film. Then, the alignment film 3 is rubbed with a cloth in a predetermined direction to perform an alignment treatment, and then a spacer having a predetermined size is kneaded into a UV curable resin on one of the substrates to form a metal screen mask shown in FIG. A frame seal for adhering the spacers in the liquid crystal display element and the upper and lower substrates to each other is printed at the same time, and is bonded to the other substrate to irradiate UV light while applying uniform pressure to cure the UV curable resin. The printing density of the spacer is 50 pieces / mm ²
A metal screen mask was prepared so that Next, the liquid crystal 10 was filled by a vacuum injection method, and the injection part was sealed with an epoxy adhesive. Polarizing plates were attached to the top and bottom of this liquid crystal cell to complete a liquid crystal display device.

At the same time, a comparative liquid crystal display device as shown in FIG. 6 was manufactured. The manufacturing method of the comparative liquid crystal display device is PET
The transparent electrode 2 is formed on the film by a low temperature sputtering method, and a predetermined pattern is formed by a photolithography method. An alignment film 3 is formed thereon by offset printing and baked to form a film. Next, the alignment film 3
After rubbing with a cloth in a predetermined direction for orientation treatment, screen print a thermosetting epoxy adhesive containing a predetermined gap material as a frame sealing material on one of the substrates, and place a spacer on the substrate. Was sprayed by a wet spray method, and the two substrates were bonded together and heated at 120 ° C. while applying a uniform pressure to cure the thermosetting epoxy adhesive to bond the upper and lower substrates. Spacer dispersion density is 50 pcs / m
It was set to m ² . Next, the liquid crystal 10 is filled by a vacuum injection method,
The injection part was sealed with an epoxy adhesive. Polarizing plates were attached to the top and bottom of this liquid crystal cell to complete a liquid crystal display device.

When the appearance of the liquid crystal display element thus manufactured was observed, color unevenness was not observed in the liquid crystal display element of the present invention, whereas in the comparative liquid crystal display element, the spacer was moved to cause a predetermined gap. As a result, the color tone became narrow and color unevenness was locally generated, and the overall color tone was changed due to excessive filling of liquid crystal.

Further, the liquid crystal display device thus produced was bent up and down so as to have an R of 50 mm, and the occurrence of color unevenness was investigated. As a result, the color unevenness was generated 10 times in the comparative product, whereas it was bent 100 times in the product of the present invention. However, the occurrence of color unevenness was not seen.

[Embodiment 3] FIG. 3 shows a cross-sectional view of a liquid crystal display device of the present embodiment. Here, 1 is an upper substrate and a lower substrate, both of which were made of PET (polyethylene terephthalate) film having a thickness of 100 μm. Reference numeral 3 is a transparent electrode made of an ITO (indium tin oxide) film, 4 is an alignment film, 5 is a spacer, 6 is a sealing material, and 7 is a liquid crystal.

In the manufacturing method of the present liquid crystal display element, the transparent electrode 2 is formed on the PET film by the low temperature sputtering method, and a predetermined pattern is formed by the photolithography method. An alignment film 3 is formed thereon by offset printing and baked to form a film. Next, the alignment film 3 is rubbed with a cloth in a predetermined direction to perform an alignment treatment, and then a UV curable resin is printed on one of the substrates with a metal screen mask shown in FIG. A frame seal to be adhered is formed at the same time, spacers of a predetermined size are sprinkled on the frame seal, and then the other substrate is attached to the frame seal, and UV light is irradiated while applying uniform pressure to cure the UV curable resin. Printing density of spacers is 100 / mm
^It was sprinkled so that it became ^2, and it was made to adhere to the UV curable resin printed previously. Next, the liquid crystal 6 was filled by a vacuum injection method, and the injection part was sealed with an epoxy adhesive. Polarizing plates were attached to the top and bottom of this liquid crystal cell to complete a liquid crystal display device.

At the same time, a comparative liquid crystal display device was manufactured. In the method of manufacturing a comparative liquid crystal display element, the transparent electrode 2 is formed on a PET film by a low temperature sputtering method, and a predetermined pattern is formed by a photolithography method. An alignment film 3 is formed thereon by offset printing and baked to form a film. Next, the alignment film 3 is rubbed with a cloth in a predetermined direction to carry out an alignment treatment, and then a thermosetting epoxy adhesive containing a predetermined gap material as a sealing material is screen-printed on one of the substrates to obtain a substrate. A spacer is sprayed onto the substrate by a wet spray method, and the two substrates are bonded together and heated at 120 ° C. while applying a uniform pressure to cure the thermosetting epoxy adhesive to bond the upper and lower substrates. .
The dispersion density of the spacers was 50 co / mm ² . Next, the liquid crystal 10 was filled by a vacuum injection method, and the injection part was sealed with an epoxy adhesive. Polarizing plates were attached to the top and bottom of this liquid crystal cell to complete a liquid crystal display device.

When the appearance of the liquid crystal display element thus manufactured was observed, color unevenness was not observed in the liquid crystal display element of the present invention, whereas in the comparative liquid crystal display element, the spacer was moved to cause a predetermined gap. As a result, the color tone became narrow and color unevenness was locally generated, and the overall color tone was changed due to excessive filling of liquid crystal.

The liquid crystal display device thus produced was bent up and down to have an R of 50 mm, and the occurrence of color unevenness was investigated. As a result, the color unevenness was generated 10 times in the comparative product, whereas it was bent 100 times in the product of the present invention. However, the occurrence of color unevenness was not seen.

[Embodiment 4] FIG. 2 shows a sectional view of a liquid crystal display element of the present embodiment. Here, 1 is an upper film substrate and a lower film substrate, both of which were made of PET (polyethylene terephthalate) film having a thickness of 100 μm. 2 is I
Transparent electrode made of TO (indium tin oxide) film,
3 is an alignment film, 4 is a spacer, 5 is a frame seal, 6 is UV
Curing resin 10 is a liquid crystal.

In the manufacturing method of the present liquid crystal display element, the transparent electrode 2 is formed on the PET film by the low temperature sputtering method, and the predetermined pattern is formed by the photolithography method. An alignment film 3 is formed thereon by offset printing and baked to form a film. Then, the alignment film 4 is rubbed with a cloth in a predetermined direction to carry out an alignment treatment, and then a UV curable resin is printed on one of the substrates by a metal screen mask shown in FIG. 3 to form a resin for adhering the upper and lower substrates. A UV-curing resin is formed by forming a frame seal for adhering the upper and lower substrates on one substrate, spraying spacers of a predetermined size on it, and then bonding the other substrate and applying UV light while applying uniform pressure. Cure. The spacers were printed so that the printing density was 100 pcs / mm ² and U was printed first.
Attached to V-cured resin. Next, the liquid crystal 10 was filled by a vacuum injection method, and the injection part was sealed with an epoxy adhesive. Polarizing plates were attached to the top and bottom of this liquid crystal cell to complete a liquid crystal display device.

At the same time, a comparative liquid crystal display device was manufactured. In the method of manufacturing a comparative liquid crystal display element, the transparent electrode 2 is formed on a PET film by a low temperature sputtering method, and a predetermined pattern is formed by a photolithography method. An alignment film 3 is formed thereon by offset printing and baked to form a film. Next, the alignment film 3 is rubbed with a cloth in a predetermined direction to carry out an alignment treatment, and then a thermosetting epoxy adhesive containing a predetermined gap material as a sealing material is screen-printed on one of the substrates to obtain a substrate. A spacer is sprayed onto the substrate by a wet spray method, and the two substrates are bonded together and heated at 120 ° C. while applying a uniform pressure to cure the thermosetting epoxy adhesive to bond the upper and lower substrates. .
The dispersion density of the spacers was 50 co / mm ² . Next, the liquid crystal 10 was filled by a vacuum injection method, and the injection part was sealed with an epoxy adhesive. Polarizing plates were attached to the top and bottom of this liquid crystal cell to complete a liquid crystal display device.

When the appearance of the liquid crystal display element thus manufactured was observed, no color unevenness was observed in the liquid crystal display element of the present invention, whereas in the comparative liquid crystal display element, a spacer was moved to cause a predetermined gap. As a result, the color tone became narrow and color unevenness was locally generated, and the overall color tone was changed due to excessive filling of liquid crystal.

Further, the liquid crystal display device thus produced was bent up and down so as to have an R of 50 mm, and the occurrence of color unevenness was investigated. As a result, the comparative product produced color unevenness 10 times, whereas the product of the present invention was bent 100 times. However, the occurrence of color unevenness was not seen. Example 5 The liquid crystal display device of the present invention prepared in Example 1 and the comparative liquid crystal display device were mounted on a card-type calculator, and a weight of 50 mm was applied to the top of the liquid crystal display device by a rubber roller.
When the presence or absence of color unevenness was investigated by rubbing at an average speed of 0 g of 50 mm / sec, the card type calculator equipped with the liquid crystal display device of the present invention did not cause color unevenness even after rubbing 1000 times, whereas the card type for comparison was used. The liquid crystal display element of the calculator is 100
Color unevenness occurred in the operation.

[Embodiment 6] The liquid crystal display device of the present invention prepared in Example 2 and a comparative liquid crystal display device were mounted on a card-type calculator, and a rubber roller having a width of 5 mm was applied on the liquid crystal display device to apply an average speed of 500 g. When the presence or absence of color unevenness was investigated by rubbing at 50 mm / sec, the card type calculator equipped with the liquid crystal display device of the present invention did not cause color unevenness even after rubbing 1000 times, whereas the liquid crystal of the comparative card type calculator. The display element showed color unevenness after 100 times. [Embodiment 7] The liquid crystal display element of the present invention prepared in Example 3 and a liquid crystal display element for comparison were respectively mounted on a card type calculator, and a weight of 50 mm was applied to the top of the liquid crystal display element by a rubber roller.
When the presence or absence of color unevenness was investigated by rubbing at an average speed of 0 g of 50 mm / sec, the card type calculator equipped with the liquid crystal display device of the present invention did not cause color unevenness even after rubbing 1000 times, whereas the card type for comparison was used. The liquid crystal display element of the calculator generated color unevenness after 10 times. [Embodiment 8] The liquid crystal display device of the present invention prepared in Example 4 and a liquid crystal display device for comparison were mounted on a card type calculator, and a weight of 50 mm was applied to the top of the liquid crystal display device by a rubber roller.
When the presence or absence of color unevenness was investigated by rubbing at an average speed of 0 g of 50 mm / sec, the card type calculator equipped with the liquid crystal display device of the present invention did not cause color unevenness even after rubbing 1000 times, whereas the card type for comparison was used. The liquid crystal display element of the calculator generated color unevenness after 10 times.

[0029]

As described above, according to the present invention, a liquid crystal display in which a pair of upper and lower substrates are provided with transparent electrodes and alignment films on the inner surfaces of the substrates and a liquid crystal is sandwiched by a spacer between the substrates. In the element, the spacer is adhered to the upper and lower substrates with a UV curable resin, and is related to a liquid crystal display element, in which color spots and local color tone changes (hereinafter referred to as color unevenness) are less likely to occur. The present invention relates to a liquid crystal display device having high display quality which can improve display characteristics and is less likely to cause color unevenness even when external stress is applied.

[Brief description of drawings]

FIG. 1 is a diagram showing a liquid crystal display element of Example 1 of the present invention.

FIG. 2 is a diagram showing a liquid crystal display element of Example 2 of the present invention.

FIG. 3 is a diagram showing a metal screen mask of the present invention.

FIG. 4 is a diagram showing a liquid crystal display element of Example 3 of the present invention.

FIG. 5 is a diagram showing a conventional liquid crystal display element.

FIG. 6 is a diagram showing a conventional liquid crystal display element.

[Explanation of symbols]

 1. Glass substrate 2. Transparent electrode 3. Alignment film 4. Spacer 5. Frame seal 6. UV curable resin 7. Polarizing plate 8. Polarizing plate with reflector 9. Film substrate 10. Liquid crystal 11. Spacer hole 12. Hole for frame seal

Claims (5)

[Claims] 1. A liquid crystal display device in which liquid crystal is sandwiched between a pair of upper and lower substrates having a transparent electrode and an alignment film formed on the inner surfaces thereof with a spacer interposed therebetween, wherein the spacer is made of a UV curable resin. A liquid crystal display device characterized by being adhered to upper and lower substrates. 2. The liquid crystal display element according to claim 1, wherein the upper and lower substrates are plastic films. 3. The liquid crystal display element according to claim 1, wherein the UV curable resin is formed at the same time as a seal for adhering the upper and lower substrates. 4. The liquid crystal display element according to claim 3, wherein the seal is made of a UV curable resin. 5. An electronic device equipped with the liquid crystal display device according to claim 1.