JP2000267589A - Apparatus for producing electrooptical device and method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for producing a liquid crystal device by which the deterioration in displayed image quality due to the lowering of the uniformity and open area ratio of the liquid crystal device is prevented. SOLUTION: The apparatus for producing each substrate of an electrooptical device used for hardening a sealing material has work coils 1a, 1b which generate an AC magnetic field, metallic heating bodies 2a, 2b which are heated by the AC magnetic field and pressing means 6a, 6b which hold a panel P, the work coils and the metallic heating bodies between them and apply pressure. The sealing material is hardened by electromagnetic induction heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology effective when applied to a manufacturing process of a device constituted by two substrates opposed to each other and joined by a resin or the like. The present invention relates to a technique suitable for use in bonding substrates of an electro-optical device utilizing the effect.

[0002]

2. Description of the Related Art In a typical liquid crystal device, a thermosetting sealing material made of epoxy resin or the like or an ultraviolet curing sealing material is applied to one of two substrates on which electrodes and an alignment film are formed. After spraying a spacer (gap material) such as a plastic ball having a diameter corresponding to the cell gap of the liquid crystal cell, the substrate on which the formation of the seal and the spacer were sprayed was opposed to the other substrate to perform alignment. Thereafter, the sealing material is cured, and the two substrates are bonded together with a predetermined space therebetween, and a liquid crystal is sealed in the space.

[0003] In the bonding step using a thermosetting sealing material, conventionally, two substrates sandwiched between jigs such as a metal plate are laminated, and a predetermined pressure is applied from both ends to an oven or the like. It was put in and heated for a predetermined time.

[0004]

However, according to the above-described technique, the peripheral portion of the substrate is heated first, and the substrate central portion is gradually heated with a delay, so that the temperature between the peripheral portion and the central portion of the substrate is increased. As a result, uniform heating by a heater is difficult. As a result, the substrate is distorted due to uneven expansion in the substrate due to the temperature gradient, and the uniformity of the liquid crystal device is reduced.

[0005] In particular, recently, as the size of the substrate has increased, the temperature gradient in the substrate has become more severe, the distortion due to uneven expansion has become considerably large, and the problem of uniformity has become more serious.

Further, plastics have been used as substrates for liquid crystal devices, and the strength and flexibility of the liquid crystal devices have been improved, but conversely, the distortion of the substrates in the bonding step has increased. .

Accordingly, an object of the present invention is to provide a technique for manufacturing a liquid crystal device which prevents the uniformity of the liquid crystal device from deteriorating and the display quality from deteriorating.

[0008]

In order to achieve the above object, an apparatus for manufacturing an electro-optical device according to the present invention applies a sealing material to the periphery of one substrate, and attaches another substrate to the substrate. What is claimed is: 1. A manufacturing apparatus comprising: a work coil configured to generate an AC magnetic field; a metal coil heated by the AC magnetic field; A heating element, the electro-optical device,
A pressurizing means for pressing the work coil and the metal heating body from both sides thereof is provided, and the sealant is cured by heat generated in the metal heating body. It should be noted that the material constituting the metal heating body is not limited as long as a current flows by electromagnetic induction, but stainless steel is considered as one of the materials which can be formed most easily and at low cost.

According to this apparatus, an AC voltage is applied to the work coil to generate an AC magnetic field, and an eddy current is generated in the metal heating body disposed in the AC magnetic field, so that the electro-optical device serving as the object to be heated is provided. Since the substrate is heated, the substrate constituting the electro-optical device can be uniformly heated, and the occurrence of distortion in the substrate can be prevented.

[0010] In the manufacturing apparatus, the metal heating element may be disposed on both sides of the electro-optical device, and the work coil may be disposed outside each of the two metal heating elements. And a pressurizing means including a pair of bases for holding the work coil.

Thus, since the electro-optical device is similarly heated from both sides, distortion between the electro-optical devices can be eliminated, and the uniformity of the entire electro-optical device can be maintained. In addition, since heating is performed from both sides of the electro-optical device, heat can be efficiently transferred to the electro-optical device, and the sealing material can be cured in a short time.

Further, in the manufacturing apparatus, the metal heating element is disposed on at least one surface of the electro-optical device, and the work coil is disposed outside the metal heating element. Pressurizing means including a pair of bases for holding the body and the work coil may be arranged and configured.

As a result, the apparatus can be simplified and downsized, and the workability can be improved.

Further, in the manufacturing apparatus, two or more of the electro-optical devices are stacked with the metal heater interposed therebetween, and the metal heaters are arranged on both sides of the stacked electro-optical device, The work coil is disposed outside each of the two metal heaters, and a pressing unit including a pair of bases that sandwich the electro-optical device, the metal heater and the work coil is disposed. it can.

Further, two or more of the electro-optical devices are laminated with the metal heating element interposed therebetween, and the metal heating element is disposed on at least one surface of the laminated electro-optical device. The work coil may be arranged outside the heating body, and a pressing unit including the electro-optical device, the metal heating body, and a pair of bases that sandwich the work coil may be arranged.

According to this device, the seal hardening process can be performed on a plurality of electro-optical devices at once, so that the productivity is improved.

Further, if the metal heating element is made of a metal layer formed on the surface of the insulating substrate in the same pattern as the sealing material, the sealing material can be efficiently cured while suppressing expansion of the substrate. Power consumption can be reduced.

In another aspect of the invention disclosed in the present application, a sealing material is applied to a peripheral portion of one substrate, another substrate is opposed to and close to the substrate with the sealing material interposed therebetween, and the sealing material is removed. This is a method for manufacturing an electro-optical device, comprising a step of curing the substrate by electromagnetic induction heating and joining the two substrates at appropriate intervals.

According to the electromagnetic induction heating, the substrate can be heated uniformly without causing a thermal gradient in the substrate, so that a highly uniform electro-optical device can be manufactured.

The electromagnetic induction heating may be performed by bonding a metal heater to at least one substrate and applying an AC magnetic field to the heater.

Thus, an AC voltage is applied to the work coil to generate an AC magnetic field, and a metal heater is arranged in the AC magnetic field to generate an eddy current. Electromagnetic induction heating can be performed.

Further, by applying the above-described apparatus for manufacturing an electro-optical device, the electro-optical device and the metal heating element are alternately stacked and laminated, and a plurality of electro-optical devices are subjected to seal hardening processing at a time. You may go.

As a result, it is possible to simultaneously cure the seals of a plurality of electro-optical devices, thereby improving the productivity.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing a schematic configuration example when the present invention is applied to a liquid crystal device manufacturing apparatus as an example of an electro-optical device.

In FIG. 1, reference numeral 4 denotes a substrate for a liquid crystal panel, and reference numeral 5 denotes a thermosetting sealing material for bonding the substrate 4, and the panel P is formed of the two substrates 4 and the sealing material 5. After the bonding step by the apparatus of the present embodiment, the liquid crystal is sealed in the panel P to form a liquid crystal panel.

Reference numerals 1a and 1b denote work coils for generating an AC magnetic field. Each of the work coils 1a and 1b is formed by winding 500 turns of a steel wire, and both ends are connected to an AC power supply so that an applied voltage can be controlled.
Of course, the work coils 1a and 1b may be configured independently of each other, and each may be connected to an AC power supply.

Reference numeral 2 denotes a metal heating plate made of a stainless steel plate having a thickness of about 2 mm.

Reference numerals 6a and 6b are bases serving as pressurizing means. One of the bases 6a and 6b is configured to be able to move up and down by a cylinder or the like, and is configured to be pressurizable by sandwiching a panel or the like between the bases 6a and 6b.

On both sides of the panel P, metal heating plates 2a, 2
b and the work coils 1a, 1b are arranged, and the bases 6a, 6b
Are arranged, the manufacturing apparatus of the present embodiment is configured.

FIG. 2 is a cross-sectional view showing another schematic configuration example when the present invention is applied to a manufacturing apparatus of a liquid crystal device as an example of an electro-optical device.

Compared with the embodiment shown in FIG. 1, the difference is that in FIG. 2, the work coil 1 is arranged only on one surface (the lower surface in the figure) of the panel P.

An AC magnetic field is generated by the work coil 1, and an eddy current is generated in the metal heating plates 2a and 2b by the AC magnetic field, and the panel P is heated by the eddy current loss. Panel P
Is thinner, the upper metal heating plate 2a can be heated by generating an eddy current in the same manner as the lower metal heating plate 2b. The metal heating plate 2a on which the work coil is not disposed can be omitted, and the base 6a may be directly in contact with the panel P.

According to this embodiment, there is an advantage that the apparatus itself can be simplified and downsized.

Further, a manufacturing apparatus which can heat-treat a plurality of panels at a time is also conceivable. FIG. 3 is an application example of the embodiment shown in FIG. 1, and FIG. 4 is an application example of the embodiment shown in FIG. 2, and is a manufacturing apparatus which can heat-treat a plurality of panels at a time.

Two panels P are arranged between the bases 6a and 6b with the metal heating plate 2c interposed therebetween. In the present embodiment, there is an advantage that an eddy current is generated in each of the metal heating plates 2a, 2b, and 2c, and the respective metal heating plates 2a, 2b, and 2C can similarly heat the panel.

Further, by sandwiching a metal heating plate between the panels, it is possible to process two or more panels at a time without impairing the uniformity, thereby greatly improving the productivity. be able to.

The apparatus for manufacturing an electro-optical device according to the present invention is not limited to the above embodiment. For example, a heat insulating means made of asbestos, silicon rubber, or the like may be formed on a surface of the metal heating plate in contact with the work coil or the base constituting the pressure means. The temperature of the metal heating plate becomes 100 ° C. or higher to cure the sealing material. However, the provision of the heat insulating means can prevent the work coil and the base from being damaged by heat.

Further, for example, in the above embodiment, the metal heating body is a single plate made of stainless steel, but it may have the same shape as the pattern of the sealing material.

FIG. 4 shows an example of the configuration of a metal heating element. Metal heating element 2 made of stainless steel on glass substrate 22
1 is formed in substantially the same shape as the seal pattern formed on the liquid crystal panel. When using a metal heating element having this configuration, the liquid crystal panel is arranged so that the sealing portion of the liquid crystal panel comes on the metal heating element formed in the same shape as the seal pattern.

By locally heating the liquid crystal panel using the metal heating body having this configuration, the sealing material can be cured while suppressing expansion of the substrate.

The bonding step using the manufacturing apparatus of the embodiment shown in FIG. 1 will be described below.

First, a sealing material 5 having a width of about 1 mm is formed on a peripheral portion of one surface of a plastic substrate 100 of 100 mm square by seal printing or the like. The sealing material 5 is formed with an opening for sealing the liquid crystal after bonding. After sealing the liquid crystal, the opening is sealed with resin. Here, the sealing material 5 uses, for example, an epoxy resin of a thermosetting resin.

Next, after the formation of the sealing material 5, the substrates on the opposite side are brought close to each other, and are inserted between the metal heating plates 2a and 2b in a state where they are aligned and joined. At this time, the cell gap is kept at about 5.8 μm.

Next, the work coils 1a and 1b are arranged outside the metal heating plates 2a and 2b, the bases 6 and 7 are arranged, and the pressure is adjusted to about 1 kg / cm ² by an air compressor. The metal heating plates 2a and 2b and the work coils 1a and 1b are supported.

Next, the work coil is driven by the AC power supply at a frequency of 60 Hz to generate an AC magnetic field. The AC magnetic flux passes through the metal heating plates 2a, 2b, and the metal heating plates 2a, 2b
An eddy current is generated in the substrate, and the eddy current is heated by the eddy current loss. The heated metal heating plates 2a and 2b uniformly heat the contacting substrate 4 and indirectly cure the sealing material.

A voltage of 1000 V for 3 hours is applied to cure the sealing material, and the substrate 4 is bonded.

In the present embodiment, the above conditions were satisfied because stainless steel was used for the metal heating element. However, even when a metal heating element of another material was used, the amount of heat required for the sealing material to harden was obtained. The condition can be determined from the heating value of the heating element.

FIG. 6 shows an active matrix type liquid crystal panel using a MIM (metal film-insulating film-diode pair having a metal film structure) as a switching device as an example of a liquid crystal device suitable for applying the present invention.

The liquid crystal panel P of this embodiment has a pixel electrode 51 made of Cr, an MIM (having a laminated structure of a TaW layer, a TaOx layer and a Cr layer) 53 as a switching device for applying a voltage to the pixel electrode 51, A data line 55 for supplying the applied voltage and A provided on the Cr pixel electrode 51
l a lower substrate 50 having a reflective electrode 57 and a transparent electrode (I
A scanning line 61 made of TO), a glass substrate (upper substrate) 60 on the incident side having a color filter layer 65, a black mask 63, and the like are arranged at appropriate intervals, and the periphery thereof is sealed with a sealant 70. TN (Twisted
A liquid crystal panel P is filled with a liquid crystal 80 such as a Nematic liquid crystal or an SH (Super Homeotropic) liquid crystal. When used as a display device,
A polarizing plate is disposed on the surface (upper surface in FIG. 5) of the glass substrate 60 on the incident side opposite to the liquid crystal.

In the liquid crystal panel of this embodiment, the central portion and the peripheral portion of the substrate are similarly heated by applying the method of the present invention. Disappears.

Although not particularly limited, in the liquid crystal panel of this embodiment, the data lines 55 formed on the liquid crystal side surface of the lower substrate 50 are arranged in one direction of the substrate (FIG. 5).
Are arranged substantially parallel to each other along a direction perpendicular to the paper surface), and the incident side glass substrate (upper substrate) 6
The scanning lines 61 formed on the surface on the liquid crystal side of 0 are arranged substantially parallel to each other along a direction intersecting the data lines.
The surface of the Al reflective electrode 57 is formed with irregularities for irregularly reflecting incident light. The reflection electrode 57 made of an Al layer is provided on the pixel electrode 51 made of a Cr layer because aluminum has a higher reflectance than chromium, and the aluminum layer is formed by omitting the Cr layer serving as an underlayer. This is because aluminum is easily oxidized on its surface and it is difficult to obtain desired characteristics.

In the embodiment shown in FIG. 6, the reflective electrode 57 made of the Al layer is provided on the pixel electrode 51 made of the Cr layer. However, the Cr pixel electrode 51 is omitted and the Al electrode is directly reflected on the surface of the substrate. The electrode 57 may be formed.

FIG. 7 shows a configuration example in which the liquid crystal panel of the above embodiment is applied as a display device of a portable telephone 200 or a portable information terminal 300.

In FIG. 7A, reference numeral 201 denotes a CP inside.
A main body having a built-in LSI such as a U or a memory, a power supply device, a speaker, etc .; 202, a lid also used as a voice input unit rotatably mounted on the main body 201; 203, a liquid crystal display using the liquid crystal panel of the above embodiment. The device is mounted such that a display surface (incident surface) comes to the inner surface of the main body 201.

In FIG. 7B, reference numeral 301 denotes a CP inside.
A main unit with a built-in LSI such as U and memory, power supply, etc.
302, a key input device provided on the upper surface of the main body 301;
Reference numeral 303 denotes a liquid crystal display device using the liquid crystal panel of the above embodiment, which is mounted so that a display surface (incident surface) comes to an inner surface of a lid portion rotatably attached to the main body 301.

In an electronic apparatus using the liquid crystal panel of the above embodiment as a display device, a backlight is not required and power consumption is low, so that it can be driven for a long time by a battery, and irregularities are formed on the surface of the reflective electrode. Therefore, the display content is easy to see, and the liquid crystal panel manufactured by applying the present invention has the advantage that the display quality is high and the uniformity is excellent because the distortion of the substrate is minimized.

The liquid crystal panel to which the present invention is applied can be used as a display device of a portable electronic device such as a mobile phone or a laptop or desktop personal computer in addition to the above-mentioned portable information terminal. The present invention can also be used for a projection display device such as a video projector using a panel as a light valve.

[0059]

As described above, the apparatus for manufacturing an electro-optical device for curing a seal material by electromagnetic induction heating according to the present invention comprises a work coil for generating an AC magnetic field, and a metal heating element heated by the AC magnetic field. And a pressurizing means for pressing the electro-optical device, the work coil and the metal heating body from both sides, and applying an AC voltage to the work coil to generate an AC magnetic field. An eddy current is generated in the metal heating element disposed inside, the electro-optical device to be heated can be heated, the substrate can be uniformly heated, and the occurrence of distortion in the substrate can be prevented. effective.

Also, a method of manufacturing an electro-optical device having a process of curing and joining a sealing material by electromagnetic induction heating while maintaining an appropriate interval between two substrates constituting the electro-optical device using the above-described manufacturing apparatus. In this case, the substrate can be uniformly heated without causing a thermal gradient in the substrate, so that an electro-optical device having high uniformity and high display quality can be manufactured.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration example when the present invention is applied to an apparatus for manufacturing a liquid crystal device as an example of an electro-optical device.

FIG. 2 is a cross-sectional view illustrating another schematic configuration example when the present invention is applied to a liquid crystal device manufacturing apparatus as an example of an electro-optical device.

FIG. 3 is an application example of the embodiment shown in FIG. 1;

FIG. 4 is an application example of the embodiment shown in FIG. 2;

FIG. 5 is a configuration example of a metal heating plate.

FIG. 6 is a sectional view showing an embodiment in which the present invention is applied to an active matrix type liquid crystal panel using an MIM as a switching device.

FIG. 7 is a perspective view illustrating a schematic configuration of a mobile phone and a portable information terminal device as examples of electronic devices to which the liquid crystal panel of the embodiment is applied as a display device.

[Explanation of symbols]

 1, 1a, 1b Work coil 2, 2a, 2b, 2c Metal heating plate (body) 3 Wiring 4 Liquid crystal panel substrate 5 Sealing material 6a, 6b Base (pressing means)

Claims (9)

[Claims] 1. A sealing material is applied to one substrate, and another substrate is made to face and approach the substrate with the sealing material interposed therebetween.
An electro-optical device manufacturing apparatus configured by joining the two substrates at appropriate intervals, comprising: a work coil that generates an AC magnetic field; a metal heating body that is heated by the AC magnetic field; An apparatus for manufacturing an electro-optical device, comprising: an optical device, a work coil, and a pressurizing unit that presses a metal heating body by sandwiching the heating device from both sides, wherein a sealant is cured by heat generated in the metal heating body. 2. The electro-optical device, wherein the metal heaters are arranged on both sides of the electro-optical device, and the work coils are respectively arranged outside the two metal heaters, and the electro-optical device, the metal heater, and the work coil are further arranged. 2. The apparatus for manufacturing an electro-optical device according to claim 1, wherein a pressurizing unit including a pair of bases for sandwiching is arranged. 3. The two or more electro-optical devices are stacked with the metal heater interposed therebetween, and the metal heaters are arranged on both sides of the stacked electro-optical device, and The work coil is arranged outside the heating body, and a pressing unit including a pair of bases for holding the electro-optical device, the metal heating body and the work coil is arranged. 2. The apparatus for manufacturing an electro-optical device according to 1. 4. The electro-optical device, wherein the metal heater is disposed on at least one surface of the electro-optical device, the work coil is disposed outside the metal heater, and the electro-optical device, the metal heater, and the work coil are further disposed. 2. The apparatus for manufacturing an electro-optical device according to claim 1, wherein a pressurizing means including a pair of bases to be sandwiched is arranged and configured. 5. The electro-optical device according to claim 1, wherein the two or more electro-optical devices are stacked with the metal heater interposed therebetween, and the metal heater is disposed on at least one surface of the stacked electro-optical device. 2. The apparatus according to claim 1, wherein the work coil is arranged outside a heating body, and a pressing unit including a pair of bases for sandwiching the electro-optical device, the metal heating body and the work coil is arranged. 3. The manufacturing apparatus for an electro-optical device according to claim 1. 6. The electro-optical device according to claim 1, wherein the metal heating element is formed of a metal layer formed on the surface of an insulating substrate in the same pattern as the sealing material. Manufacturing method. 7. A sealing material is applied to a peripheral portion of one substrate, another substrate is opposed to the substrate with the sealing material interposed therebetween, and the sealing material is heated and cured to cure the two substrates. What is claimed is: 1. A method for manufacturing an electro-optical device, comprising a step of bonding substrates at appropriate intervals, wherein the sealing material is cured by electromagnetic induction heating. 8. The method according to claim 7, wherein the electromagnetic induction heating is performed by bonding a metal heater to at least one substrate and applying an AC magnetic field to the heater. . 9. A sealing material is applied to a peripheral portion of one substrate, another substrate is opposed to the substrate with the sealing material interposed therebetween, and the sealing material is heated and cured to cure the two substrates. 6. The method of manufacturing an electro-optical device according to claim 3, further comprising a step of bonding the substrates at appropriate intervals, wherein a plurality of the electro-optical devices and the metal heater are alternately stacked and stacked. A method for manufacturing an electro-optical device, comprising: performing a seal hardening process on a plurality of electro-optical devices at once using an optical device manufacturing apparatus.