JP3632457B2 - Manufacturing method of liquid crystal device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a liquid crystal device.
[0002]
[Prior art]
Conventionally, a method for manufacturing a liquid crystal panel is mainly a method in which two substrates are bonded together via a spacer and a seal, and several tens of substrates are stacked, and a predetermined pressure is applied to the entire uppermost substrate to perform a curing process. A schematic configuration of this manufacturing method is shown in FIG. A dummy substrate 403 for height adjustment between a surface plate 401, 402 having a certain interval, a slip sheet 404 for reducing concentrated load due to foreign matter mixing, and a panel substrate 405 obtained by bonding the two substrates together. Stacking and injecting gas into a rubber plate (commonly called balloon) 406 fixed on the upper surface plate and applying arbitrary pressure to the panel substrate form a panel having a predetermined cell thickness. Further, as an improvement method of the above method, there is a method described in an example of JP-A-5-113571. In this method, a substrate bonded with a seal is put in a resin film bag, the resin film bag is sealed under reduced pressure, and heated under the curing conditions of the seal. The seal is cured.
[0003]
[Problems to be solved by the invention]
However, in the method of applying pressure by stacking panel substrates, the method of applying load and heat is greatly different between the upper side and the lower side of the stacked substrates, and due to variations in the thickness of the substrates used and contamination by foreign substances, etc. Uniform pressure is not applied. Therefore, cell thickness unevenness is likely to occur in the finished liquid crystal panel. The method described in the example of JP-A-5-113571 is relatively good in cell thickness uniformity, but the panel substrate surface and the resin film are in direct contact with each other, so It is easy to be charged with static electricity, and it is easy to cause destruction of panel elements due to static electricity. Furthermore, since stacking panel substrates has the same problem as the above method, there is a problem that the number of sheets that can be processed is limited. In addition, the use of a resin film bag results in poor workability and facilitates entry of foreign substances and the like.
[0004]
Accordingly, an object of the present invention is to solve the above-described problems and to provide a method for forming a cell thickness of a panel accurately and stably.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, a method for manufacturing a liquid crystal device according to the present invention is a method for manufacturing a liquid crystal device in which two substrates are bonded via a seal member, and liquid crystal is sealed in an inner region of the seal member, Providing the sealing member between the substrates, providing an enclosing frame having an opening so as to surround the sealing member, setting an inner region of the enclosing frame to a first atmospheric pressure, and the first The step of holding the inner region of the sealing member at the first atmospheric pressure by closing the opening of the enclosure frame in the atmospheric pressure, and after the opening of the enclosure frame is blocked, from the first atmospheric pressure A step of curing the sealing member at a high second atmospheric pressure, and a step of cutting the substrate between the sealing member and the surrounding frame after the sealing member is cured, The surrounding frame In the step of providing, the width of the cutting portion of said enclosure frame in the step of cutting the substrate, characterized by narrower than the width of the other portions of the surrounding frame.
[0006]
According to the method for manufacturing a liquid crystal device of the present invention, pressure can be applied to two bonded substrates without using a rigid body, so that the pressure and temperature are uniformly transmitted to the substrates. In addition, even when there are variations in the thickness of the substrate, foreign matter, etc., there is no pressure unevenness at all. Therefore, the same pressure is uniformly applied to the panel substrate, and the concentrated load due to the mixing of foreign substances and the like as seen in the prior art is not applied to the substrate at all, so that there is no cell thickness unevenness caused by the concentrated load. Furthermore, since there is no stacking of the liquid crystal panels during the crimping process, there is no peeling work, and there is an effect that defects due to static electricity are difficult to occur.
In addition, since the width of the cutting part of the surrounding frame is formed to be narrower than the width of the other part of the surrounding frame, when the substrate is cut, the break (cutting) of the part that causes a step in the upper and lower substrates, for example, the electrode terminal portion ), And a decrease in yield due to breakage, chipping, etc. of the substrate during a break is prevented.
[0007]
In the method for manufacturing the liquid crystal device, it is preferable that the opening of the surrounding frame is provided in the vicinity of a liquid crystal injection port provided in the seal member.
In this case, the liquid crystal injection port can be efficiently degassed, so that a differential pressure is hardly generated between the inner region and the outer region of the seal member, and the seal is not easily broken.
[0008]
Moreover, it is preferable that one of the sealing member and the surrounding frame is a thermosetting resin and the other is an ultraviolet curable resin.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
( Reference Example 1)
FIG. 1 is a diagram showing a main part of a first reference example relating to a method of manufacturing a liquid crystal device according to the present invention. Explaining the configuration, alignment film application and rubbing treatment are performed on the glass substrate 101 on which the switching elements are formed and the glass substrate 102 having a color filter, respectively. Next, an epoxy thermosetting resin in which silica balls 103 serving as spacers are mixed in a portion corresponding to a seal pattern (seal member) 104 on the glass substrate 101 is drawn by a dispenser method, and corresponds to a resin pattern (enclosure frame) 105. Acrylic ultraviolet curable resin was drawn on the part from another nozzle. Also, resin balls 106 are dispersed on the glass substrate 102, the substrates 101 and 102 are bonded to each other, and irradiated with ultraviolet rays to cure the resin pattern 105. Next, the bonded substrate is put in a vacuum apparatus, and the gaps 107 and 108 surrounded by the resin pattern 105 are reduced to 7.6 * 10 −3 Torr. Thereafter, the opening 109 of the resin pattern is formed in this pressure atmosphere. The seal pattern 104 was cured while being coated and cured with an ultraviolet curable resin 110 and further heating the substrate in an atmospheric pressure atmosphere. The substrate was cut along a panel shape by inserting a cutting line 111, and finally liquid crystal was injected and sealed to prepare a liquid crystal panel. Here, the width of the portion (corresponding to the cutting line) corresponding to the cutting line 111 of the resin pattern (enclosure frame) 105, that is, the width of the cutting portion is set to the width of the other portion of the resin pattern 105 as will be described later. By forming it thinner than the width, the present reference example 1 becomes an embodiment of the present invention. The panel obtained by this production method was excellent in cell thickness uniformity, and the cell thickness distribution at 16 points in the panel was measured. As a result, σ was ± 0.02 μm, which was very good. For comparison, the panel produced by the conventional crimping method shown in FIG. 4 had a cell thickness variation σ of ± 0.05 μm to ± 0.1 μm. Further, although the device destruction due to static electricity slightly occurred in the conventional method, it was not observed at all in the panel of this example, and a liquid crystal panel with high display quality was obtained. Further, the pressure atmosphere that covers the opening 109 of the resin pattern 105 is changed to 380, 100, 7.6, 7.6 × 10 ⁻¹ , 7.6 × 10 ⁻² , 1 × 10 ⁻³ Torr other than the above. In other cases, when the liquid crystal panel was prepared under the same conditions, the cell thickness variation σ of the obtained panel was ± 0.07 μm at 380 Torr, ± 0.03 μm at 100 Torr, 7.6, 7.6 × 10−1, 7. Even at 6 × 10 ⁻² and 1 × 10 ⁻³ Torr, it was ± 0.03 μm to ± 0.01 μm, and excellent cell thickness uniformity was obtained particularly at a pressure of 100 Torr or less.
[0015]
( Reference Example 2)
A second reference example relating to the method of manufacturing a liquid crystal device of the present invention will be described with reference to FIG. The difference from Reference Example 1 was that the inside of the resin pattern 105 was not decompressed, and the opening 109 was coated and cured with an ultraviolet curable resin 110 in an air atmosphere. Thereafter, the glass substrate was placed in a 3 kgf / cm ² pressure kettle and heated to the curing temperature of the seal pattern 104 to prepare a liquid crystal panel. The liquid crystal panel obtained by this production method had good cell thickness uniformity, and the variation σ of the measured cell thickness at 16 points in the panel showed a value of ± 0.03 μm. Furthermore, there was no element destruction or orientation failure due to static electricity, and the display quality was good. Further, when the curing pressure of the seal pattern 104 after covering the opening 109 of the resin pattern was changed to 0.5, 1, ² , 4, 5 kgf / cm ^{2 in} addition to the above, the cell thickness variation σ was measured. 5 kgf / cm ² at ± 0.07 .mu.m, excellent cell thickness uniformity 1,2,4,5kgf / cm at ² respectively are ± 0.03 .mu.m particularly 1 kgf / cm ² or more pressure was obtained.
Also in this example, the width of the portion corresponding to the cutting line 111 (the portion corresponding to the cutting line) of the resin pattern (enclosure frame) 105, that is, the width of the cutting portion, is described below. This reference example becomes an embodiment of the present invention by forming it thinner than the width of other portions.
[0016]
( Reference Example 3)
A third reference example related to the method for manufacturing a liquid crystal device of the present invention will be described with reference to FIG. The difference from Reference Examples 1 and 2 is that after the pressure inside the resin pattern 105 is reduced to 1 × 10 ⁻¹ Torr, the opening 109 is coated and cured with an ultraviolet curable resin 110, and this substrate is further heated by 1 kgf / cm ² . It was put in a pressure cooker and heated to the curing temperature of the seal pattern 104. The liquid crystal panel obtained by this manufacturing method had good cell thickness uniformity, and the variation σ of the measured cell thickness at 16 points showed a value of ± 0.02 to 0.03 μm. In addition, good results were obtained with respect to the destruction of elements and poor alignment due to static electricity. Moreover, the pressure which closes the opening part 109 of a resin pattern is 760 (atmospheric pressure) other than the above, 380, 100, 7.6, 7.6 * 10 < ^-1 >, 7.6 * 10 <-2>, ¹ * 10 < ^-3 >. In addition to the above, the curing pressure of the seal 104 after sealing the opening 109 of the resin pattern was changed to 0.5, ² , 4, 5 kgf / cm ² and the cell thickness variation σ was measured. In the combination of 760 Torr for sealing the opening 109 and 0.5 kgf / cm ² for the curing pressure of the seal pattern 104, the cell thickness variation σ was slightly large as ± 0.07 μm, but the other combinations were ± 0.02 The value was 0.03 μm and the uniformity was good.
Also in this example, the width of the portion corresponding to the cutting line 111 (the portion corresponding to the cutting line) of the resin pattern (enclosure frame) 105, that is, the width of the cutting portion, is described below. This reference example becomes an embodiment of the present invention by forming it thinner than the width of other portions.
[0017]
( Reference Example 4)
FIG. 2 is a diagram showing a main part of another reference example related to the method for manufacturing a liquid crystal device of the present invention. In the present embodiment, a configuration in which alignment direction of the opening 212 of the aperture 209 and the seal pattern 204 of the resin pattern 205 as shown in FIG. 2 (a), the other is created a liquid crystal panel in the configuration of Example 1 . The panel obtained by this manufacturing method did not cause any deformation or breakage of the seal at the time of decompression, and the seal width was uniform, and the cell thickness uniformity varied with an excellent value of ± 0.01 μm. A liquid crystal panel with extremely high display quality was obtained.
Also in this example, the width of the portion corresponding to the cutting line 111 (the portion corresponding to the cutting line) of the resin pattern (enclosure frame) 105, that is, the width of the cutting portion, is described below. This reference example becomes an embodiment of the present invention by forming it thinner than the width of other portions.
[0018]
( Example)
FIG. 3 is a diagram showing the main part of one embodiment of the method for manufacturing a liquid crystal device of the present invention. In this embodiment, as shown in FIG. 3, the cutting line equivalent portion 313 of the pattern width of the resin pattern 305 is as thin as about 1 mm, and the other portion is about 3 mm. Other than that, a liquid crystal panel having the configuration of Reference Example 1 was prepared. The panel obtained by this manufacturing method can be easily broken at the panel size, especially at the upper and lower substrates, such as the electrode terminal portion, and the yield is reduced due to substrate cracks, chips, etc. There wasn't. The width of the resin pattern can be arbitrarily set depending on the material substrate configuration to be used, and is not limited to the dimensions of this embodiment as long as the pressure in the pattern can be maintained until the seal is cured.
[0019]
(Reference Example 5 )
A reference example relating to the manufacturing method of the liquid crystal device of the present invention will be described with reference again to FIG. In the present embodiment, using the material of PET (polyethylene terephthalate) resin film of the resin pattern 105 of FIG. 1, it is created a liquid crystal panel in the configuration of Example 1 other place. According to this manufacturing method, the resin film is in close contact with the substrate when the pressure in the resin pattern 105 is reduced, and the pressure can be sufficiently maintained, the uniformity of the obtained panel is good, and the cell thickness variation σ is ± 0.03 μm. It was. Moreover, it was reusable several times as a resin pattern because of the film. Furthermore, even when polyethylene, nylon, or tetron resin was used in place of the PET film, the differential pressure until the seal was cured was good.
Also in this example, the width of the portion corresponding to the cutting line 111 (the portion corresponding to the cutting line) of the resin pattern (enclosure frame) 105, that is, the width of the cutting portion, is described below. This reference example becomes an embodiment of the present invention by forming it thinner than the width of other portions.
[0020]
The above-mentioned examples and reference examples show a part of the present invention, and in these examples and reference examples , the description is given in the combination configuration of the switching element and the color filter substrate, but in the substrate configuration without the switching element and the color filter. Can be made in the same manner, and the material can be plastic, silicon, a ceramic substrate, or the like.
[0021]
Also, regarding the material and combination of the seal and the resin pattern, the seal pattern is described as a thermosetting resin, and the resin pattern is described as an ultraviolet curable resin. If the curing conditions are shifted, they can be produced in the same manner, and materials such as room temperature curable resins such as completely different silicone resins may be used. Further, even if the sealing pattern in the substrate has a number of sealing shapes of two or more panels, or there is a dummy sealing pattern, the same effect can be expected if a resin pattern is provided around it.
[0022]
【The invention's effect】
As described above, according to the method for manufacturing a liquid crystal panel of the present invention, since the cell thickness uniformity of the liquid crystal panel can be remarkably improved, not only the display performance of the TFT, MIM, and STN panel is further improved, but also the gap accuracy is improved. It can be applied to FLC (ferroelectric liquid crystal), BTN (bistable chiral nematic liquid crystal) panels and the like which are more demanded. Further, since the panel substrate is not pressed by a metal, an insulator, etc., there is no element destruction due to static electricity such as peeling charging, and a great effect is obtained for improving the yield.
In addition, since the width of the cutting part of the surrounding frame is formed to be narrower than the width of the other part of the surrounding frame, when the substrate is cut, the break (cutting) of the part that causes a step in the upper and lower substrates, for example, the electrode terminal portion ), And a decrease in yield due to breakage, chipping, etc. of the substrate during a break is prevented.
[Brief description of the drawings]
FIGS. 1A and 1B are diagrams illustrating a main part of a structure of a liquid crystal device according to Reference Example 1, Reference Example 2, Reference Example 3, and Reference Example 5 according to the present invention , in which FIG. 1A is a plan view, and FIG. FIG.
FIGS. 2A and 2B are diagrams showing a difference in air flow due to a difference in the direction of the resin pattern opening and the injection port in Reference Example 4 according to the present invention , wherein FIG. The figure which reversed the part.
[3] in Example of the present invention, it is an enlarged view of the intersection portion of the cutting line and the resin pattern, (a) shows the overall view substrate, (b) 3 13 enlarged view of.
FIG. 4 is a schematic plan view showing a crimping configuration in the prior art.
[Explanation of symbols]
101, 102 Glass substrate 103 Silica ball 104 Seal pattern 105 Resin pattern 106 Resin ball 107, 108 A space surrounded by the resin pattern 109 Resin pattern opening 110 UV curable resin 111 Cutting line 204 Seal pattern 205 Resin pattern 209 Resin pattern opening Portion 212 Seal pattern opening 305 Resin pattern 313 Cutting line equivalent portion 401, 402 Surface plate 403 Dummy substrate 404 Interleaf 405 Panel substrate 406 Rubber plate (balloon)

Claims (3)

A method of manufacturing a liquid crystal device in which two substrates are bonded via a seal member, and liquid crystal is sealed in an inner region of the seal member,
Providing the sealing member between the substrates, and providing an enclosing frame having an opening so as to surround the sealing member;
A step of setting the inner region of the surrounding frame to a first atmospheric pressure;
Maintaining the inner region of the seal member at the first atmospheric pressure by closing the opening of the surrounding frame in the first atmospheric pressure;
Curing the seal member in a second air pressure higher than the first air pressure after closing the opening of the surrounding frame;
Cutting the substrate between the sealing member and the surrounding frame after curing the sealing member, and
In the step of providing the surrounding frame, the width of the cut portion of the surrounding frame in the step of cutting the substrate is formed to be narrower than the width of the other portion of the surrounding frame. . 2. The method of manufacturing a liquid crystal device according to claim 1, wherein the opening of the surrounding frame is provided in the vicinity of a liquid crystal injection port provided in the seal member. 3. The method of manufacturing a liquid crystal device according to claim 1, wherein one of the sealing member and the surrounding frame is a thermosetting resin, and the other is an ultraviolet curable resin.

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