JP2000010506A - Production of color el display device and method for adhering translucent substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a color EL display device having good strength of adhesion by packing a thermosetting resin between a color filter substrate and an EL(electroluminescence) element substrate over the entire surface without generating air bubbles. SOLUTION: The one surface 24a of the EL element substrate 24 is provided with EL element parts 23. These EL element parts 23 are protected by a protective sealing part 25. A recess 44 is formed by etching at the EL element substrate 24 on the side opposite to the side provided with the EL element parts 23 in such a manner that its peripheral edge remains to a frame shape. At the time of adhering and fixing the EL element 21 and color filters 32, the thermosetting resin is dropped to a projecting shape to the other surface 24b of the EL element substrate 24 and the color filter substrate 22 and the EL element substrate 24 are brought into tight contact with each other to force spread the resin 33 between the color filters 32 and the EL element substrate 24, by which the resin is packed between the substrates. As a result, the resin may be packed between the substrates without generating the air bubbles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method of manufacturing a color EL (electroluminescent) display device applied to various flat and thin display devices and a method of bonding a light-transmitting substrate used therein.

[0002]

2. Description of the Related Art With the development of the information technology industry in recent years, there is an increasing demand for a flat and thin display device having a light weight and a low space occupancy. Among the devices applied to such flat-panel display devices, thin-film EL devices are being actively developed as display devices having excellent display quality because they are self-luminous and have good visibility.

A thin-film EL element has a structure in which at least one of two electrodes including a transparent electrode, an insulating layer and a light emitting layer sandwiched between the two electrodes is provided on a glass substrate. Light emission can be obtained by applying an AC electric field. Currently, ZnS: Mn, which is a light emitting layer material that has high luminous efficiency and emits light stably, is in practical use.
There is only a yellow monochrome display device using layers, and a color EL display device is being developed in order to expand industrial applications.

There are roughly two types of structures of color EL display devices. One is a juxtaposition method in which light-emitting layers having different emission colors are juxtaposed and formed by etching and patterning, and the other is a color filter method in which a single light-emitting layer is spectrally separated by a color filter to perform color display. . At present, the development of the color filter method is mainly being promoted because of the simplicity of preparation.

As a color filter system, a structure in which an upper electrode of an EL element is used as a light-transmitting electrode so that light can be extracted from the upper electrode side, and a color filter is arranged in proximity to the upper electrode of the EL element; EL device
A method in which light is extracted from the element substrate and a color filter is formed on the EL element substrate side is considered.
The former is different from the monochrome EL display currently in practical use, in that the upper electrode is made of ITO (indium tin oxide) and the color filter has to be brought close to the upper electrode of the EL element. However, there is a problem that the life characteristics are deteriorated because the seal layer used for the thin film becomes thin.

On the other hand, the latter has an advantage that the structure of a monochrome EL display device conventionally put to practical use can be used as it is. However, the EL element substrate is 1 m
Since the color filter has a thickness of about m, the color filter and the EL element cannot be brought close to each other. In order to solve such a problem, the applicant of the present application disclosed in Japanese Patent Application No. 10-168086 "Method for manufacturing color electroluminescent display device and color electroluminescent display device", after manufacturing an EL device, an EL device substrate. By processing the thinner by etching, the problem of a decrease in the viewing angle due to color shift was solved.

FIG. 8 is a sectional view showing the above-described conventional color EL display device 1. As shown in FIG. The color EL display device 1
An L element 5 and a color filter substrate 9,
The EL element 5 includes a light-transmitting EL element substrate 3, an EL element portion 2, and a seal portion 4. The color filter substrate 9 includes a light-transmitting substrate 7 and a color filter 8.

A color EL display device 1 is manufactured by fitting and adhering a color filter substrate 9 into a recess 10 formed in the EL element substrate 3. 10 is not formed, and the EL element 5 is
The EL element section 2 is formed on the element substrate 3, and a sealing substrate 12 of the sealing section 4 is provided. Thereafter, the air in the space formed between the sealing substrate 12 and the EL element substrate 3 is sucked from the injection hole 11 formed in the sealing substrate 12 to create a vacuum. 2 Inject silicone oil for protection and seal. Thereafter, a recess 10 is formed in the EL element substrate 3 by etching, the thickness of the EL element substrate 3 where the color filter 8 is disposed is reduced, and the color filter substrate 9 is fitted into the recess 10. The color EL display device 1 is assembled by bonding. E
Since the color EL display device 1 is manufactured by fitting the color filter substrate 9 into the recess 10 of the L element substrate 3, the color EL display device 1 has large mechanical strength.

Since the EL element substrate 3 has a large thickness when silicon oil is injected by vacuum suction, it is possible to prevent the EL element substrate 3 from cracking during vacuum suction, and to further prevent the EL element substrate 3 from being etched. Since the color EL display device 1 is manufactured by fitting the color filter substrate 9 after reducing the thickness, the distance between the color filter 8 and the EL element portion 2 is reduced, and the reduction of the viewing angle due to color shift is prevented.

When the color filter substrate 9 and the EL element 5 are bonded to each other, a photocurable resin 13 is interposed between the color filter substrate 9 and the EL element substrate 3 so that the light-transmitting substrate of the color filter substrate 9 is formed. The color filter substrate 9 and the EL element substrate 3 are bonded by irradiating light from the 7 side to cure the photocurable resin 13.

[0011]

However, since the color filter 8 blocks light such as ultraviolet rays necessary for curing the photocurable resin, the photocurable resin 13 is
And the EL element substrate 3 cannot be cured. Therefore, the photo-curable resin 13 is applied to the color filter substrate 9 only at the periphery of the light-transmitting substrate 7 where the color filter 8 is not provided.
And the EL element substrate 3. This causes a problem that the adhesive strength is reduced.

When an adhesive layer is filled between the EL element substrate 3 and the color filter substrate 9 for adhesion, if there is no adhesive layer, that is, if bubbles are generated, the refractive index of the part is not equal to that of the surrounding part. That is, when displayed, the shape of the bubble appears on the display surface, which degrades the display quality.

When two translucent glass substrates are bonded, a method of applying a thin adhesive to the surface of one glass substrate and then bringing the two substrates into close contact with each other is adopted. In such a case, a slight undulation is formed on the surface. When the undulations come into contact with the substrate, a gap is formed between the substrate and the adhesive. When there is no escape space for the air in the gap, the gap remains as a bubble.

As a method of bonding two substrates without generating such bubbles, for example, Japanese Patent Application Laid-Open No. 63-183
Japanese Patent Application Laid-Open No. 626 discloses a method of blowing air bubbles by spinner rotation after bonding a substrate.
Japanese Patent No. 78497 discloses a method of tilting a substrate so as to prevent air bubbles from being mixed by using a device for controlling the angle of the substrate when the substrates are bonded, and Japanese Patent Application Laid-Open No. 3-126646 discloses a method. Discloses a method for controlling the thickness of the adhesive layer so that the thickness of the adhesive layer monotonically increases from one side end to the other side end when applying the adhesive to the substrate, thereby preventing the generation of air bubbles at the time of bonding the substrates. Has been
Japanese Patent Application Laid-Open No. 6-349962 discloses a bonding method in which the center of glass having a high center is melted and bonded to prevent the generation of bubbles. However, each of the bonding methods disclosed in each of these publications requires a device having a complicated configuration separately, and has a problem that the manufacturing cost is increased. Therefore, a simpler bonding method is desired in order to expand the industrial use.

A first object of the present invention is to provide a color EL device in which an EL element substrate and a color filter substrate are bonded with high strength.
A second object of the present invention is to provide a method of manufacturing a display device, and to provide a method of bonding a light-transmitting substrate in which bubbles are not mixed.

[0016]

According to the present invention, a first electrode, a light emitting layer, and a second electrode having a light-transmitting property are formed on one surface of an EL element substrate having a light-transmitting property. Preparing an EL element that emits EL light from the other surface of the EL element substrate, and a color filter substrate provided with a color filter on one surface of a light-transmitting substrate; Fill the thermosetting resin between the surface of the filter substrate on which the color filter is provided,
The color E is characterized by being thermally cured and then bonded.
It is a manufacturing method of an L display device.

According to the present invention, a thermosetting resin is filled between the surface of the color filter substrate on which the color filter is provided and the other surface of the EL element substrate, and then the thermosetting resin is heated. After curing, the color filter substrate and the EL element are bonded. Conventionally, a photocurable resin cannot be cured in a region where a color filter is provided because a photocurable resin is used for adhesion between a color filter substrate and an EL element substrate. By heating by using the resin, the resin can be cured even in a region where the color filter is provided, and the color filter substrate and the EL element substrate can be bonded to each other. Thus, the color filter substrate and the EL element substrate can be bonded to each other with the adhesive layer interposed over the entire surface on which the color filter is provided.
Sufficient adhesive strength is obtained.

According to a second aspect of the present invention, in the method for bonding two substrates, at least one of which is a light-transmitting substrate, the liquid curable resin is dropped on one of the substrates so as to protrude upward. Thereafter, the two substrates are brought into close contact with each other, the liquid curable resin is spread out, the space between the substrates is filled, and the substrate is cured.

According to the present invention, the liquid curable resin is dropped in a chevron shape so as to protrude on one substrate, that is, to have one convex portion, and then the other substrate is placed on the one substrate. The two substrates are brought into close contact with each other by pressing against the liquid curable resin. At this time, since the liquid curable resin is raised in a convex shape, a portion where the liquid curable resin and the other substrate come into contact with each other becomes one top portion of the liquid curable resin. The reactive resin is spread radially from the top and filled between the substrates. When the convex liquid curable resin is spread in this manner, no void is formed in the resin, and the resin can be filled between the substrates while preventing the generation of air bubbles. After filling, the two substrates can be bonded by curing the liquid curable resin. In this way, the substrates can be adhered by a simple method without introducing air bubbles, and the manufacturing cost can be reduced.

According to a third aspect of the present invention, there is provided a method for bonding two substrates, at least one of which is a light-transmitting substrate.
The liquid curable resin is dropped onto the two substrates so as to protrude in a convex shape, and then the two substrates are brought into close contact with each other so that the apexes of the resin portions of the two substrates come into contact with each other. This is a method for bonding a light-transmitting substrate, which is characterized by being spread out, filled, and cured.

According to the present invention, when the two substrates are brought into close contact with each other such that the tops of the liquid curable resin dropped in a convex shape on the two substrates come into contact with each other, the two substrates are brought into one resin portion. When the two substrates are brought into close contact with each other, the liquid curable resin is radially pushed out from one resin portion, and the resin is filled between the substrates without generating bubbles. By dropping the liquid curable resin on both substrates in this way, compared to the case where the liquid curable resin is dropped only on one substrate, even if the filling amount is the same, the substrate contacted by the dropped resin Is reduced, whereby it becomes possible to fill the resin between the substrates while further preventing air bubbles from being mixed. Further, the manufacturing cost can be reduced by such a simple bonding method.

According to a fourth aspect of the present invention, in the method for bonding two substrates, at least one of which is a light-transmitting substrate, the liquid curable resin is applied to one of the substrates at a plurality of positions along a straight line or zigzag shape. This is a method for bonding a light-transmitting substrate, wherein the liquid is dropped so as to protrude to a convex shape, and then the two substrates are brought into close contact with each other, a liquid curable resin is spread between the substrates, filled and cured. .

According to the present invention, the liquid curable resin is dropped at a plurality of positions along a straight line or a zigzag shape, and then the two substrates are brought into close contact with each other, so that even a rectangular substrate can be efficiently used as a liquid. It is possible to spread and fill the curable resin over the entire surface of the substrate. Further, in the present invention, although the liquid curable resin is dropped at a plurality of positions, since each liquid curable resin is arranged along a straight line or a zigzag shape, when each resin is spread out, a gap is formed between the resins. It is prevented from being left. Therefore, it is possible to prevent the generation of air bubbles and to fill the entire surface of the substrate with resin evenly even with a rectangular substrate efficiently. Further, the manufacturing cost can be reduced by such a simple bonding method.

According to a fifth aspect of the present invention, the liquid curable resin according to the present invention is a liquid curable resin whose viscosity decreases when heated when heated, so that the resin between the substrates can be spread while heating the substrates. It is characterized in that a force is applied to the substrate.

According to the present invention, when the liquid curable resin is dropped at normal temperature, the liquid curable resin has a high viscosity, so that it can be dropped in a large raised convex shape. Thus, a sufficient amount of liquid curable resin necessary for filling between the substrates can be suitably dropped in a convex shape. When the substrate is heated, the viscosity of the liquid curable resin is reduced. When a force is applied to the substrate, the liquid curable resin is pushed out thinly, and the liquid curable resin can be thinly and uniformly filled between the substrates.

According to a sixth aspect of the present invention, when the EL element substrate and the color filter substrate are bonded to each other, the liquid thermosetting resin is dropped on one of the substrates so as to protrude in a convex shape. The substrates are brought into close contact with each other, and the thermosetting resin is spread and filled between the substrates, and the EL element substrate and the color filter substrate are aligned with each other. Are fixed, and then heated to cure the thermosetting resin to bond the two substrates.

According to the present invention, the liquid thermosetting resin is dropped onto one of the substrates and then brought into close contact with the two substrates, whereby the liquid thermosetting resin is filled between the substrates without generating bubbles. can do. A photocurable resin is provided in a portion where the color filter is not provided between the substrates, and the alignment between the EL element substrate and the color filter substrate is performed by aligning the electrode pattern of the EL element with the color filter pattern of the color filter substrate. After that, light is irradiated to cure the photocurable resin, thereby temporarily fixing the EL element substrate and the color filter substrate, and then heating to cure the thermosetting resin to bond the two substrates together. As described above, since the substrate can be aligned at room temperature and temporarily fixed and then heated and cured, the problem that the alignment must be performed while being heated and cured can be solved.

According to a seventh aspect of the present invention, when the EL element substrate and the color filter substrate are bonded to each other, the thermosetting resin is dropped on each substrate so as to protrude in a convex shape, and the resin of the two substrates is dropped. The two substrates are brought into close contact with each other so that the vertices of the parts are in contact with each other, and the thermosetting resin is spread and filled between the substrates, and the color filter is placed in a state where the EL element substrate and the color filter substrate are aligned. It is characterized in that the two substrates are fixed with a photocurable resin in a portion not provided, and then the two substrates are bonded by heating to cure the thermosetting resin.

According to the present invention, the two substrates are brought into close contact with each other so that the tops of the liquid thermosetting resin dropped in a convex shape on the EL element substrate and the color filter substrate are brought into contact with each other, so that the air bubbles can be more reliably formed. The resin can be filled between the substrates while preventing mixing of the resin. Also, a color filter substrate and an EL
Since the element substrate is temporarily fixed by the photocurable resin in a state where the element substrate is positioned at room temperature by the photocurable resin, it is not necessary to perform the alignment when heating and curing.

According to the present invention, when the EL element substrate and the color filter substrate are bonded to each other,
The thermosetting resin is dropped at a plurality of points along a straight line or a zigzag shape so as to protrude, and the two substrates are brought into close contact with each other, and the thermosetting resin is spread and filled between the substrates. In a state where the element substrate and the color filter substrate are aligned, both substrates are fixed with a photocurable resin in a portion where no color filter is provided, and then the thermosetting resin is cured by heating and the two substrates are bonded. It is characterized by the following.

According to the present invention, the liquid thermosetting resin is dropped on one of the substrates at a plurality of positions along a straight line or a zigzag shape, so that even if the substrates are rectangular, bubbles are generated between the two substrates. And the liquid thermosetting resin can be uniformly and effectively filled without causing the generation. Further, since the color filter substrate and the EL element substrate are temporarily fixed at room temperature with the photocurable resin in the aligned state, there is no need to perform the alignment at the time of heat curing.

According to a ninth aspect of the present invention, the thermosetting resin of the present invention is a thermosetting resin whose viscosity decreases when heated when heated, so that the resin between the substrates can be spread out when the substrates are heated. And applying a force to the substrate.

According to the present invention, when a droplet is dropped on a substrate at room temperature, the droplet can be suitably raised in a convex shape and dropped due to high viscosity. When the substrate is heated and cured, the viscosity of the liquid curable resin decreases, so the resin spreads thinly and evenly between the substrates and is filled. Substrate and E
The L element substrate is bonded. Since the thickness of the adhesive layer is reduced in this manner, a decrease in the viewing angle due to color shift is prevented.

[0034]

FIG. 1 is a sectional view showing a color EL display device 20 manufactured by a method for manufacturing a color EL display device according to an embodiment of the present invention. Color E
The L display device 20 is configured by bonding an EL element 21 and a color filter substrate 22, and the EL element 21 includes a light-transmitting EL element substrate 24, an EL element portion 23, and a seal portion 25. The color filter substrate 22 includes a light-transmitting substrate 31 and a color filter 32.

The EL element 21 is composed of a first electrode 26 as an EL element portion 23 and a first electrode 26 on an EL element substrate 24 made of glass.
Insulating film 27, light emitting layer 28, second insulating film 29, second electrode 3
0 is a double-insulating thin-film EL element in which
The electrode 26 is made of ITO (indium tin oxide) with a thickness of about 100 nm on one surface 24a of the EL element substrate 24 by an electron beam evaporation method or a high frequency sputtering method.
A stripe is formed by wet etching using a photoresist.

The first insulating film 2 laminated on the first electrode 26
7 is an SiO ₂ film having a thickness of about 40 nm and a
It is made of a laminated film of about ₃ m Si ₃ N ₄ films and is manufactured by a high frequency sputtering method. Light-emitting layer 2 laminated on first insulating film 27
In No. 8, a ZnS: Mn layer is formed to a thickness of about 7000 ° by an electron beam evaporation method using ZnS: Mn as an evaporation source. The EL light-emitting layer 28 includes the first and second electrodes 26,
By applying an AC electric field between the light-emitting devices 30, a yellow light emission including a red to green light-emitting region is exhibited, and a red and green multi-color EL display device can be produced by dispersing light with red and green color filters. . In the present embodiment, such a light-emitting layer 28 is used because a monochrome EL display device using such a light-emitting layer has already been practically used, and is a light-emitting layer material excellent in light emission luminance, light emission stability, and the like. This is because it has been confirmed. Color E in which the present invention is implemented
The L display device is not limited to such a red and green multicolor EL display device. For example, ZnS: Mn
And a SrS: Ce light-emitting layer, and emits red,
It is also possible to produce a full-color EL display device by separating light with green and blue color filters.

The second insulating film 29 laminated on the light emitting layer 28
Is, for example, a Si ₃ N ₄ film having a thickness of about 100 nm and a
It is made of a laminated film of about 5 nm of SiO ₂ film, and each is manufactured by a high frequency sputtering method. After forming the second insulating film 29, high vacuum annealing is performed to improve the crystallinity of the light emitting layer. The high vacuum annealing is performed by heating and holding at 630 ° C. in a high vacuum of 1 × 10 ⁻⁴ Pa or less.

Finally, 500 n of Al is used as the second electrode 30.
An EL element portion 23 is completed by heating and vapor-depositing a film having a thickness of about m and forming a stripe shape perpendicular to the first electrode 26 by wet etching using a photoresist.

The moisture-proof seal portion 25 of the EL element 21 is manufactured by arranging a protective glass 42 dug to a depth of about T1 = 1 mm so as to seal the EL element portion 23 in the dug portion. The edge of the protective glass 42 is E
The one surface 24a of the L element substrate 24 is bonded using an epoxy resin 38. Thereafter, silicone oil mixed with silica gel is injected into the sealing space 37 containing the EL element portion 23 from the oil inlet 35 previously formed on the protective glass 42, and the inlet is sealed with the sealing glass 36. Stop and make. When injecting silicone oil, the air in the sealed space 37 is exhausted from the oil inlet 35 to remove the sealed space 3.
With the inside of the chamber 7 evacuated, the silicone oil is sucked from the oil inlet 35 to fill the sealing space 37 with the silicone oil. Thus, when the oil is filled, the sealed space 3
Since it is necessary to evacuate the inside of the device 7, the EL element substrate 24 has a thickness that can withstand such a vacuum when filled with oil.

After the EL element part 23 and the moisture-proof seal part 25 are formed on the EL element substrate 24, the EL element substrate 24 is etched by hydrofluoric acid (hydrofluoric acid).
The recess 44 is formed in the EL element substrate 24 on the side opposite to the side where the EL element section 23 is provided, so that the thickness T2 of the portion facing the element section 23 is about 100 μm. At this time, considering the mounting of the color filter substrate 22, the peripheral portion of the EL element substrate 24 remains in a frame shape, and the color filter substrate 2
Only the portion where 2 is fitted is etched into a concave shape. By forming the recess 44 in the EL element substrate 24 in this manner, the EL element 21 and the color filter substrate 22 are formed.
Means that the color filter substrate 22 is
Are bonded and fixed in a state of being fitted, the bonding strength is increased, and the color EL display device 20 has sufficient mechanical strength. Further, since the EL element substrate 24 interposed between the EL element section 23 and the color filter 32 is thinned by etching, the distance between the first electrode 26 of the EL element section 23 and the color filter 32 is reduced. As a result, a decrease in the viewing angle due to color shift is prevented, and a large viewing angle can be secured.

The color filter 32 is formed on the EL element substrate 24.
Forming directly on the other surface 24b, which is the bottom surface of the concave portion 44, and bonding the substrate 31 thereon;
Is formed on the other surface 24b of the EL element substrate 24.
There is a method of bonding to. In the latter, an adhesive layer is interposed between the color filter 32 and the EL element substrate 24, so that the thickness of the adhesive layer affects the viewing angle. It is necessary to directly form the color filter 32 on the other surface 24b, and the production is difficult. Therefore, in the present embodiment, the latter method, which is easy to produce, is adopted.

The color filter 32 of the color filter substrate 22 has one surface 31a of a light-transmitting glass substrate.
The red and green filters R and G are alternately arranged on the upper side, and a black filter BK is formed between the filters R and G. The EL of such a color filter substrate 22 and the EL element 21
The element substrate 24 is the surface of the color filter substrate 22 on the color filter 32 side, that is, the surface of each of the filters R, G, and BK facing the other surface 24b of the EL element substrate 24 and one surface 31a of the substrate 31 and the EL element substrate. A thermosetting synthetic resin 33 is filled and bonded between the other surface 24b and the other surface 24b. The substrate 3 on which the color filter 32 is not provided
The one surface 31a and the EL element substrate 24 are fixed at least at two points (both ends of the substrate 31 in FIG. 1) by the photocurable resin 40, and the color filter substrate 22
The gap formed between the substrate and the EL element substrate 24 is filled with the silicon resin 41. Thus, the color filter substrate 22 and the EL element 21 are bonded with a large strength.

Next, the EL element 21 and the color filter substrate 2
2 shows an outline of a method of bonding with No. 2. First, a color filter substrate 22 and an EL element 21 are prepared as shown in FIG.
On the other surface 24b of the EL element substrate 24 of the L element 21, a thermosetting resin 33 such as an FA sealer 1017C (trade name) protrudes in a mountain shape having one convex portion as shown in FIG. Drops. The thermosetting resin 33 has no air bubbles mixed therein and has such a viscosity that it does not spread thinly when dropped, but protrudes in a convex shape as described above. No. 33 is 1500-3000 cp at room temperature 25 ° C. to satisfy such conditions.
s viscosity. On the other hand, on the color filter substrate 22, at least two points on the one surface 31a of the substrate 31 where the color filter 32 is not provided,
Put.

Thereafter, as shown in FIG.
6 makes the EL element 21 and the color filter substrate 22 adhere to each other. The adhesion jig 46 has an EL substrate support 45 and a pressing member 47, and first mounts the EL element 21 on the EL substrate support 45 so that the other surface 24b of the EL element substrate 24 faces upward. The color filter substrate 22 is placed on the EL element 21 such that the color filter 32 of the color filter substrate 22 faces the other surface 24b of the EL element substrate 24, and the pressing member 47 is on the opposite side to the side where the color filter 32 is provided. The color filter substrate 22 is pressed from the surface to bring the color filter substrate and the EL element substrate 24 into close contact with each other. As a result, the thermosetting resin 33 dropped so as to protrude in a convex shape is spread radially, and the thermosetting resin 33 is filled between the substrates.

When the thermosetting resin 33 is dropped, as shown in FIG. 4A, it passes through the center of the EL element substrate 24 in the width direction and moves in the longitudinal direction according to the rectangular EL element substrate 24. A plurality of thermosetting resins 33 are dropped at equal intervals along the extending center line A1 at three locations in this embodiment. When the substrates 21 and 22 are opposed to each other and pressed in a direction approaching each other, the vertices of the convex resin first come into contact with the opposed substrate, and each resin portion is spread radially around the top portion, so that the entire surface between the substrates To be filled. As shown in FIG. 4B, when the thermosetting resins 33 are dropped so as to be juxtaposed in two rows as shown in FIG. When each of the resin portions dropped at the four points of the square shape is spread, the resin spreads over the entire surface of the substrate with a void left at the center of the four points as shown in FIG. 4B. As a result, there is no escape for the air trapped in the voids, and air bubbles remain between the substrates. On the other hand, in the present embodiment, by dropping the thermosetting resin 33 in a straight line, no void is formed as shown in FIG. Can come off.

After the substrates 21 and 22 are brought into close contact with each other and the thermosetting resin 33 is filled between the substrates, the position of the color filter substrate 22 is adjusted by aligning the electrode pattern of the first electrode 26 with the pattern of the color filter 32. After the alignment, the portion where the photocurable resin 40 is provided is irradiated with ultraviolet rays to cure the photocurable resin 40, and the color filter substrate 22 and the EL element 21 are temporarily fixed. Since the photo-curable resin 40 is provided in a portion where the color filter 32 is not formed as described above, the ultraviolet light is not absorbed by the color filter, and the photo-curable resin 40 is surely cured to be cured.
And the EL element 21 can be temporarily fixed.

Next, the filled thermosetting resin 33 is cured. When the thickness of the adhesive layer of the thermosetting resin 33 is large, the viewing angle of the color EL display device 20 is affected, but the viscosity of the thermosetting resin (FA sealer) 33 used in the present embodiment is 25 ° C. at room temperature. At 1500-3000 cps
Because of its high viscosity, the thermosetting resin 33 at room temperature
It is difficult to push strongly.

The thermosetting resin 33 used in the present embodiment
Is reduced in viscosity by heating, for example, at 100 ° C., which is the temperature immediately before thermosetting, at 100 cps.
The viscosity decreases to a degree or less, and heat cures at 110 ° C. Therefore, as shown in FIG. 5, the color EL display device 20 is placed on a jig capable of applying a force to the formation portion of the color filter 32 of the color filter substrate 22, and the entire color EL display device 20 is placed in an oven and cured by heating. Thereby, the thermosetting resin 33 can be hardened by being spread thinly. In this embodiment, the jig that applies a force to the formation portion of the color filter 32 is a color filter 32 of the color filter substrate 22 in a state where the color EL display device 20 is placed on the support base 51 with the EL element 21 side down. It is assumed that the weight 50 is mounted on the formation portion and the pressing force acts so that the two substrates 22 and 24 come close to each other.
The display device 20 is placed in an oven, and the oven is heated to 110 ° C., which is the temperature at which the thermosetting resin 33 thermally cures.
The viscosity of the thermosetting resin 33 decreases during heating,
When the color filter forming portion is pressed by the weight 50, the portion 33 is thinly spread and filled over the entire surface between the substrates. As described above, the resin 33 is thinly spread out, and is thermoset when the temperature of the thermosetting resin 33 reaches 110 ° C., so that the color filter substrate 22 and the EL element 2 are hardened.
1 will be completely adhered. At this time, since the EL element 21 and the color filter substrate 22 are temporarily fixed in a state where they are aligned, it is possible to prevent the EL element 21 and the color filter substrate 22 from being mutually shifted and adhered and fixed. In addition, the area to be pressed is the formation part of the color filter 32 of the color filter substrate 22 because the adhesive part by the photocurable resin 40 has already been cured, and the gap is maintained in the photocurable resin part even during heating. For this reason, when the weight 50 is mounted between two points of the cured photo-curable resin 40, no pressing force acts on the central portion of the color filter substrate 22. Further, since the resin is spread by applying a force to the substrate by lowering the viscosity, it is possible to easily spread the resin thinly without requiring a large force.

As described above, the thermosetting resin 33 is cured in a state of being spread thinly and uniformly, so that the thickness of the resin layer is reduced and the problem of color shift due to the viewing angle does not occur.
In addition, since the thermosetting resin can be filled between the substrates without generating bubbles, deterioration in image quality can be prevented.

Finally, the silicon resin 41 is injected into the gap between the color filter substrate 22 and the EL element substrate 24, and the color EL display device 20 is completed.

FIG. 6 is a plan view showing a drop position of the thermosetting resin 33 dropped on the EL element substrate 24 in a method of manufacturing a color EL display device according to another embodiment of the present invention. Except for the drop position, the manufacturing method is the same as that shown in FIGS.

The size of the EL element substrate 24 used in the present embodiment is 26 cm in width L 1 and 8 cm in length L 2. As shown in FIG. 6, the thermosetting resin 33 is dropped on each vertex of the rectangular EL element substrate 24 along the zigzag line A2 as shown in FIG. The interval L3 adjacent to each of the dropped thermosetting resins 33 in the vertical direction is 4 cm, the interval L4 in the horizontal direction is 2 cm, and the bending angle θ inside the zigzag bent line A2 is 90 ° <θ. ≦ 180 ° is selected. If the bending angle θ is less than 90 °, voids are formed at the center of the three points when the thermosetting resins 33 at the three points adjacent to each other are radially pushed and spread, respectively, which causes bubbles. Would. The bending angle is 180 °
Indicates that it becomes a straight line.

By dropping the thermosetting resin 33 in a zigzag shape as described above, the rectangular EL element substrate 24 is formed.
Even in this case, the thermosetting resin can be uniformly spread and filled over the entire surface between the substrates.

In addition, the droplet is not limited to dropping on each vertex of the zigzag line A2, but may drop on a straight line portion. In addition, the droplet may be dropped not only in a zigzag shape but also along a wavy line.
Is selected in the range of 90 ° C. <θ ≦ 180 °, whereby the resin can be filled between the substrates without generating bubbles.

FIG. 7 shows an EL element 2 in a method of manufacturing a color EL display according to still another embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a state in which the color filter substrate 1 and a color filter substrate 22 are bonded together. In this embodiment, only the manufacturing method and the bonding method of the color EL display device shown in FIGS. 1 to 5 are different, and the other manufacturing steps are the same, so that the description is omitted.

In the present embodiment, the thermosetting resin is not limited to dropping at three places on the EL element substrate 24 in a convex shape, but also drops at three places on the color filter 32 of the color filter substrate 22. I do. When the substrates 22 and 24 are bonded to each other, the droplets are dropped at positions where the tops of the thermosetting resins 33 that have dropped in a convex shape are in contact with each other. In this way, the two substrates 22 and 2 are contacted so that the tops of the resin portions contact each other.
When the substrates 4 are brought into close contact with each other, the resin spreads radially around the top, so that the resin can be filled between the substrates without generating bubbles. By adhering the two substrates 22 and 24 so that the pair of resins are in contact with each other, it is possible to reduce the amount of droplets per spot with the same filling amount, so that the resin that has dropped can be spread. The droplets can be suitably dropped in a convex shape. Further, in the present embodiment, the drop position is not limited to the case of dropping in a straight line, but drops in a zigzag shape on both the color filter substrate 22 and the EL element substrate 24, and each of the dropped thermosetting resins. The color filter substrate 22 and the EL element substrate 2 are arranged such that the tops are in contact with each other.
4 may be adhered.

As still another embodiment of the present invention, in a method of manufacturing a color EL display device having a square shape, for example, a thermosetting resin is dropped at a central portion of an EL element substrate 24 to drop a color filter substrate. And the EL element substrate, and the color filter substrate 22 and E
The thermosetting resin may be dropped on the center portions of both sides of the L element substrate 24 so that the top portions come into close contact with each other.

In each of the above embodiments, the photocurable resin is placed on the color filter substrate 22 and then the substrates 22 and 24 are brought into close contact with each other. , 24 may be manufactured by injecting a photocurable resin 40 into a gap between the EL element substrate 24 and the color filter substrate 22 and curing the resin by ultraviolet irradiation. In each of the embodiments described above,
The number of drops of the thermosetting resin is not limited to one at each location, and a plurality of drops may be dropped at one location and raised in a convex shape. This makes it possible to increase the filling amount.

[0059]

According to the first aspect of the present invention, a color EL display device having a high adhesive strength is provided by filling a thermosetting resin between the two substrates of a color filter substrate and an EL element substrate and curing by heating. Can be created.

According to the second aspect of the present invention, bubbles are generated by dropping the liquid curable resin onto one of the substrates in a convex shape, and then bringing the two substrates into close contact and spreading the resin. Thus, the resin can be reliably filled between the substrates. In this manner, the resin can be easily filled without leaving bubbles between the translucent substrates without using a complicated device.

According to the third aspect of the present invention, the liquid curable resin is dropped on both substrates in a convex shape, and the two substrates are brought into close contact with each other so that the tops are in contact with each other. Can be reduced, and the resin can be filled between the substrates without dropping in a suitable convex shape and generating bubbles.

According to the fourth aspect of the present invention, the liquid curable resin is dropped at a plurality of locations along the zigzag shape on one substrate, so that even a rectangular transparent substrate can be covered over the entire surface. The resin can be effectively spread and filled between the substrates.

According to the fifth aspect of the present invention, by heating when two substrates are brought into close contact with each other, the viscosity of the liquid curable resin is reduced, and the resin is thinly and evenly spread between the substrates to adhere to each other. It is possible to do. Since the viscosity is high when the resin is dropped, the resin can be suitably dropped in a convex shape. If the viscosity is low at the time of dropping, it spreads thinly on the substrate, and when the two substrates are brought into close contact with each other, a gap is formed, which causes bubbles to remain. By dropping the droplets, the droplets can be suitably dropped into a mountain-shaped convex shape, and the resin can be spread without generating bubbles. By applying a force to the substrates while heating, the resin can be thinly filled between the substrates.

According to the present invention as set forth in claim 6, according to claim 2,
By manufacturing a color EL display device using the method for bonding a light-transmitting substrate described in (1), a thermosetting resin can be filled without generating bubbles between the substrates. In addition, when the EL element substrate and the color filter substrate are aligned with each other when the substrates are brought into close contact with each other, light is applied to the photocurable resin to temporarily fix the substrates, so that the alignment of the substrates can be performed at room temperature. It is possible to do with. If such temporary fixing is not performed, there arises a problem that the two substrates must be aligned while heat-curing the thermosetting resin. However, such a problem is solved and productivity is improved. .

According to the present invention as set forth in claim 7, according to claim 3,
By applying the method for bonding a light-transmitting substrate shown in (1) to the method for manufacturing an EL display device, it is possible to prevent the generation of bubbles by dropping the resin in a suitable convex shape. In addition, when the EL element substrate and the color filter substrate are aligned with each other when the substrates are brought into close contact with each other, light is applied to the photocurable resin to temporarily fix the substrates, so that the alignment of the substrates can be performed at room temperature. It is possible to do with. If such temporary fixing is not performed, there arises a problem that the two substrates must be aligned while heat-curing the thermosetting resin. However, such a problem is solved and productivity is improved. .

According to the present invention described in claim 8, according to claim 5,
By applying the method for bonding a light-transmitting substrate described in (1) to the method for manufacturing an EL display device, it becomes possible to spread and fill the resin over the entire surface between the substrates even in the case of a rectangular substrate. In addition, when the two substrates are brought into close contact with each other, the two substrates are temporarily fixed by irradiating light of a photocurable resin in a state where the EL element substrate and the color filter substrate are aligned, so that the alignment of the two substrates is performed at room temperature. It is possible to do with. If such temporary fixing is not performed, there arises a problem that the two substrates must be aligned while heat-curing the thermosetting resin. However, such a problem is solved and productivity is improved. .

According to the ninth aspect of the present invention, a sixth aspect is provided.
In the method for manufacturing a color EL display device described in any one of Items 8 to 8, the resin between the substrates can be spread out by applying a force so that the two substrates adhere to each other at the time of heating, and the resin can be thinly filled between the substrates. The thickness of the adhesive layer can be reduced. This makes it possible to manufacture a color EL display device that does not cause the problem of color shift due to the viewing angle.

[Brief description of the drawings]

FIG. 1 shows a color EL display device 2 manufactured by a method for manufacturing a color EL display device according to an embodiment of the present invention.
FIG.

FIG. 2 shows a color filter substrate 22 and an EL element substrate 2
FIG.

FIG. 3 is a cross-sectional view showing a state where the color filter substrate 22 and the EL element substrate 24 are bonded together.

FIG. 4 is a plan view showing a state where droplets are dropped on an EL element substrate 24.

FIG. 5 is a cross-sectional view showing a state when the color EL display device 20 is heated.

FIG. 6 is a plan view showing a state in which a thermosetting resin 33 is dropped on an EL element substrate 24 in a method of manufacturing a color EL display device according to another embodiment of the present invention.

FIG. 7 shows a color filter substrate 22 and a color filter substrate E in a method of manufacturing a color EL display device according to still another embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a state when the L element substrate 24 is bonded.

FIG. 8 is a sectional view showing a conventional color EL display device.

[Explanation of symbols]

 Reference Signs List 20 color EL display device 21 EL element 22 color filter substrate 23 EL element part 24 EL element substrate 25 sealing part 26 first electrode 27 first insulating film 28 light emitting layer 29 second insulating film 30 second electrode 31 substrate 32 color filter 33 Thermosetting resin 40 Photocurable resin

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 4G061 AA31 BA07 CB04 CB16 CD02 CD18 DA29 DA32 DA36 DA42 5C094 AA08 AA31 AA36 AA38 AA43 BA27 CA24 DA13 EA05 EB02 ED03 GB10

Claims (9)

[Claims] 1. A light-transmitting first electrode, an EL light-emitting layer, and a second electrode are formed on one surface of a light-transmitting EL element substrate, and emit EL light from the other surface of the EL element substrate. An EL element and a color filter substrate on which a color filter is provided over one surface of a light-transmitting substrate are prepared. The other surface of the EL element substrate and the surface of the color filter substrate on which the color filter is provided are provided. A method for manufacturing a color EL display device, characterized in that a thermosetting resin is filled in the gap, and then thermosetting is performed for bonding. 2. A method of bonding two substrates, at least one of which is a translucent substrate, wherein a liquid curable resin is dropped onto one of the substrates so as to protrude, and then the two substrates are brought into close contact with each other. A method for bonding a light-transmitting substrate, wherein the liquid curable resin is spread out, filled between the substrates, and cured. 3. A method of bonding two substrates, at least one of which is a light-transmitting substrate, wherein a liquid curable resin is dropped on each of the two substrates so as to protrude in a convex shape, and then the resin of both substrates is formed. 2 so that the vertices of the part touch each other
A method for bonding a light-transmissive substrate, comprising: bringing two substrates into close contact with each other, spreading a liquid curable resin between the substrates, filling and curing the resin. 4. A method of bonding two substrates, at least one of which is a light-transmitting substrate, wherein the liquid curable resin is raised on one of the substrates in a linear or zigzag manner at a plurality of locations. A method of adhering a light-transmitting substrate, comprising: dropping, thereafter, bringing two substrates into close contact with each other, spreading and filling a liquid curable resin between the substrates, and curing the resin. 5. The liquid curable resin is a liquid curable resin having a viscosity lower than that of a normal temperature when heated, and applying a force to a substrate so as to spread the resin between the substrates while heating the substrate. The method for bonding a light-transmitting substrate according to any one of claims 2 to 4, wherein 6. When bonding an EL element substrate and a color filter substrate, a liquid thermosetting resin is dropped on one of the substrates so as to protrude, and the two substrates are brought into close contact with each other to be thermoset. In the state where the EL element substrate and the color filter substrate are aligned with each other, the two substrates are fixed with a photo-curable resin at a portion where the color filter is not provided, and then heated. 2. The method for manufacturing a color EL display device according to claim 1, wherein the thermosetting resin is cured to bond the two substrates. 7. When bonding the EL element substrate and the color filter substrate, a thermosetting resin is dropped on each substrate so as to protrude in a convex shape, and the vertices of the resin portions of both substrates come into contact with each other. The two substrates are brought into close contact with each other to spread and fill the thermosetting resin between the substrates. In addition, the EL element substrate and the color filter substrate are aligned with each other, and the photocuring is performed at a portion where the color filter is not provided. 2. The method for manufacturing a color EL display device according to claim 1, wherein the two substrates are fixed with a conductive resin, and then the two substrates are bonded by heating to cure the thermosetting resin. 8. When bonding the EL element substrate and the color filter substrate, the thermosetting resin is dropped on one of the substrates so as to protrude in a convex shape at a plurality of positions along a straight line or a zigzag shape. The two substrates are brought into close contact with each other, and the thermosetting resin is spread and filled between the substrates, and at the same time, the EL element substrate and the color filter substrate are aligned with each other. 2. The method for manufacturing a color EL display device according to claim 1, wherein the two substrates are fixed, and thereafter, the thermosetting resin is cured by heating to bond the two substrates. 9. The thermosetting resin is a thermosetting resin whose viscosity decreases when heated when heated, and applies a force to the substrate so as to spread the resin between the substrates when the substrate is heated. 9. The method according to claim 6, wherein:
The method for manufacturing a color EL display device according to any one of the above.