JP2014102490A - Panel bonding method and panel bonding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a panel bonding method to bond a liquid crystal panel and a touch panel to each other using a resin in the atmosphere causing no squeeze-out of resin or air bubble trapped therein.SOLUTION: The panel bonding method is for bonding a second panel 2 to a first panel 1. A resin 3 is applied to entire surface of the first panel 1 in a rectangular shape. At this time, a pair of the opposing sides L1 and L2 and the other pair of the opposing sides W1 and W2 at the periphery of the resin 3 are formed to be higher than the inner surface 4a applied with the resin 3 and to be different in height between the sides L1 and L2 and the sides W1 and W2. After applying the resin 3 over the surface, the entire periphery thereof is allowed get semi-cured. After positioning the first panel 1 and the second panel 2 to face each other, the second panel 2 is brought into close contact with the first panel 1, the resin 3 surely cured entirely.

Description

The present invention relates to a method of bonding a first panel and a second panel entirely with a resin.
Specifically, the bonding of a touch panel and a display panel, the bonding of a protective panel to an organic EL device, and the like can be given as examples. The display panel is a flat display panel, such as a liquid crystal display device, a plasma display, or an organic EL panel.

In recent years, as a method for disposing a transparent touch panel on a display panel, a method in which the display panel and the transparent touch panel are entirely bonded with a liquid adhesive is becoming mainstream.
By filling the gap between the display panel and the transparent touch panel with a transparent liquid adhesive whose refractive index is close to that of glass or acrylic, the visibility of the display panel due to light reflection or refraction at the air layer interface between the display panel and the transparent touch panel Is greatly improved.

  As the liquid adhesive, an ultraviolet curable resin is mainly used. An ultraviolet curable resin is filled in the gap between the display panel and the transparent touch panel, and the liquid adhesive is cured by irradiating the ultraviolet curable resin with ultraviolet rays.

The merit of using the ultraviolet curable resin as the liquid adhesive is that it is liquid and can follow the unevenness of the bonding surface and can be cured in a short time by irradiation with ultraviolet rays.
However, when the display panel and the transparent touch panel are bonded to each other, the liquid ultraviolet curable resin entrains air, and bubbles tend to remain on the bonding surface. Furthermore, the liquid UV curable resin protrudes outside the filling region. These disadvantages cause the appearance failure due to bubbles and the conduction failure caused by the protruding UV curable resin adhering to the electrode terminal.

Three typical methods for bonding a display panel and a transparent touch panel will be described.
− Flip method −
In this flip method, an ultraviolet curable resin is dropped onto a transparent touch panel, and then the transparent touch panel with its front and back reversed is reversed and superimposed on the display panel in parallel. Then, the air is pushed out and bonded together while spreading the UV curable resin outward from the center. In this flip method, a transparent touch panel and a display panel are bonded together in an atmosphere that does not use vacuum.

− Roller system −
In this roller method, an ultraviolet curable resin dropped and applied onto a display panel is overlapped with one end of a display panel and a transparent touch panel, and then moved and bonded together using a roller. In this flip method, a transparent touch panel and a display panel are bonded together in an atmosphere that does not use vacuum.

− Vacuum system −
In this vacuum method, the flip-type bonding is performed in a vacuum chamber so that air bubbles do not enter between the display panel and the transparent touch panel.

  In each of these three typical bonding methods, UV curing of at least one of the opposing surfaces of the display panel and the transparent touch panel is performed in advance for the purpose of preventing the liquid UV curable resin from sticking out of the filling region during bonding. Generally, a method is used in which the UV curable resin is linearly raised and applied around the resin filling area, and the UV curable resin raised in a linear shape is semi-cured to form a dam and then bonded. It has been.

  Furthermore, in the flip method and the roller method in which bonding is performed in the atmosphere, in order to prevent air from being trapped by the spread of the ultraviolet curable resin at the corners of the dam provided around the filling region, Some ideas have been devised, such as opening some corners to allow air to escape.

  In the case of the flip method, the UV curable resin is bonded so as to expel bubbles by expanding radially from the center in all directions, but in particular, it is difficult to control the protrusion of the UV curable resin on the long side, There are cases where the UV curable resin protrudes beyond the filling region beyond the dam, or air bubbles are involved when the UV curable resin spreads, causing a problem that bubbles remain in the bonding surface.

This improvement measure is disclosed in Patent Document 1 and Patent Document 2.
Patent Document 1 discloses a method in which a predetermined amount of a UV curable resin is dropped onto a bonding surface of a transparent touch panel or a display panel, and a linear shape is formed so as to connect the UV curable resin at a plurality of points applied in a dotted manner. A step of applying the UV curable resin to the transparent touch panel or the display panel, a step of forming a dripping on the UV curable resin applied in a dot-like manner, and a step so as not to apply an impact to the dripping. It is provided with a step of bringing into contact with the adherend and further expanding and filling the ultraviolet curable resin and a step of curing the ultraviolet curable resin.

This Patent Document 1 is an improvement in a flip system in which a plurality of points of UV-cured resin are tied in a linear shape and the spreading method of the coating is made more uniform.
FIG. 15 shows a bonding apparatus in Patent Document 2.

  Patent Document 2 is an improvement in a roller system so that bubbles do not remain in the bonding surface. In this bonding apparatus, the second panel 101 is bonded to the first panel 103 via the ultraviolet curable resin 102 by running the roller 100. The second panel 101 has a starting end 101 a that is first bonded to the first panel 103 and a terminal end 101 b that is finally bonded to the first panel 103. The end 101b is controlled by a pillow 104 that can be moved up and down to support the lower surface of the second panel 101 so as to restrict the downward movement, and the end 101b is not yet pressed by the roller 100. The first panel 103 is prevented from contacting.

JP 2009-48214 A JP 2011-53503 A

  In the case of the flip method, Patent Document 1 discloses that a plurality of ultraviolet curable resins applied in a dotted manner are applied in a linear form so as to tie them and spread uniformly in a bonding region. The spreading method of the resin is not necessarily uniform, and a certain waiting time is required until the ultraviolet curable resin reaches the dam, so that the tact time is increased. Further, it is necessary to optimize the application conditions such as the position and amount of application of the ultraviolet curable resin depending on the panel size, the state of the adhesive surface, the properties of the ultraviolet curable resin, etc., and this takes time.

  In the case of the roller method, in Patent Document 2, in a region not yet pressed by the roller 100, a second panel 101 (for example, a touch panel) and a first panel 103 (for example, a display panel) coated with an ultraviolet curable resin are used. The lower surface of the second panel 101 is supported by a pillow 104 that can be moved up and down, and the lowering of the pillow 104 is controlled while controlling the curvature of the second panel 101 according to the movement of the roller 100. There is. Therefore, since the mechanism of the apparatus is complicated in order to control each moving axis in cooperation with each other, there is a problem that the apparatus becomes expensive. Furthermore, since the display panel has a large deflection due to its own weight as the first panel 103 becomes thinner and larger, it becomes difficult to hold the panel with the pillow 104 and control each moving axis, and the panel size is limited. Has a problem.

  In the case of the vacuum system, the equipment cost increases due to the large equipment such as the vacuum chamber and the vacuum pump for evacuating the inside of the vacuum chamber, and the time required for evacuation becomes longer and the tact time becomes longer. There is a problem.

  Furthermore, in any of the flip method, roller method, and vacuum method, the UV curable resin that has been dropped and applied is bonded together while being spread out, and a dam is used to prevent the UV curable resin from protruding outside the filling area. It is essential to provide it.

  For this reason, as a facility for forming a dam by linearly raising an ultraviolet curable resin around the filling region, for example, a dispenser capable of high-precision discharge and a stage having an XYZ axis for moving the dispenser are required. There is a problem that the equipment cost becomes high. In addition, the dam needs to prepare a high-viscosity resin separately from the filling resin in order to maintain the raised shape, which increases the material cost. In addition, the resin used for the dam and the ultraviolet curable resin used for filling differ in properties such as viscosity, curing shrinkage, and strength, and a bonding interface between the two resins may appear after the main curing, which causes a quality problem.

  Here, the touch panel is bonded to the display panel as an example, but the same problem occurs when the protective panel is bonded to protect the organic EL layer of the organic EL device. .

  In the present invention, when the first panel and the second panel are bonded with a liquid adhesive, even if the first panel and the second panel are bonded together in the air without providing a dam, the liquid adhesive sticks out of the filling region, or bubbles remain. It aims at providing the panel sticking method and panel sticking apparatus which do not produce the malfunction of this at low cost.

  In the panel sticking method of the present invention, when the second panel is stuck to the first panel with a resin, the surface of the first panel and one surface of the facing surface of the second panel are orthogonal to a pair of opposing sides. The resin is applied in a rectangular shape by raising the periphery from the inside so that the height of the other pair of sides is different, the periphery of the applied resin is semi-cured, and the first panel and the second After the panels face each other and are brought into close contact with each other, the entire resin is fully cured.

  Moreover, the panel sticking apparatus of this invention is such that the height of the other pair of sides orthogonal to the pair of sides facing each other is different on one surface of the first panel and the second panel that are stuck together. A coating device that swells the periphery from the inside and applies the resin in a rectangular shape; a first curing device that semi-cures the periphery of the applied resin; and a facing device that faces the first panel and the second panel And a deforming device that deforms one surface of the opposing surface of the first panel or the second panel into a curved shape, and the resin between the first panel and the second panel facing each other by reducing the distance between them in parallel. A lifting and lowering device that is brought into close contact with each other, a release device that releases the deformation of the curved shape, and a second curing device that fully cures all of the resin interposed between the first panel and the second panel. It is characterized by

  According to the panel sticking method of the present invention, it is not necessary to expand the resin used for bonding at the time of bonding the first panel and the second panel to the filling region, and only the first panel and the second panel are in close contact with each other. One panel and the second panel can be bonded together.

  From this, there is no protrusion of the resin accompanying the bonding, or the amount thereof is very small, and since the periphery of the applied resin is semi-cured, the flow of the resin is suppressed, and the resin flows out of the filling region. The resin does not protrude. Furthermore, the waiting time for the spread of the resin is not required.

  Since the periphery of the resin applied to the filling region is raised from the application surface, the height of the other pair of sides orthogonal to the pair of opposing sides is different from that of the first panel. The second panel is faced, closely contacted along a pair of sides with higher swell around the applied resin, and swelled from the center of the pair of sides with higher swell along the outer side. The gap between the panels can be regulated by the pair of sides with the higher side, and the air when pasting together while expanding the contact area is discharged from the gap between the pair of sides with the lower swell and the overlapped panel. As a result, no bubbles remain.

Furthermore, the bonding time can be shortened by bonding from the center of the pair of sides with higher bulge of the resin toward the end in the outer direction.
Further, according to the display device manufacturing apparatus of the present invention, the surroundings of the resin applied to the filling region can be raised, so that a state similar to the case where a dam is formed in advance before the resin is applied as in the prior art can be obtained. As a result, facilities for forming dams are not required. Bonding is a simple mechanism that expands the adhesion to the entire surface of the filling region by releasing the deformation of the curved shape after bringing the panel deformed into the curved shape into contact with the center of the filling region where the resin is applied. Since it can be performed, a complicated mechanism is unnecessary.

(A) sectional view and (b) plan view of a liquid crystal display module with a touch panel manufactured according to Embodiment 1 of the present invention (A) plan view and (b) cross-sectional view of a state in which an ultraviolet curable resin is applied to the liquid crystal display panel in the manufacturing process of the embodiment. The perspective view of the application | coating state of the ultraviolet curable resin in FIG. 3A is a sectional view in the L direction and FIG. 3B is a sectional view in the W direction. In the slit die coater used in the same embodiment, (a) a sectional view of a die, (b) a sectional front view thereof, and (c) a sectional front view of a die of a comparative example Sectional drawing of the bonding process of the embodiment (A) A sectional view of a panel pasting device used in the embodiment, and (b) to (f) sectional views of the pasting process. (A) Top view and (b) Cross-sectional view of an organic EL device manufactured according to Embodiment 2 of the present invention In the same embodiment, (a) a plan view and (b) a cross-sectional view of the lower substrate in a coating process in the case of manufacturing a large number in a batch Sectional drawing explaining the die | dye of the die coater used for the same embodiment Sectional view before individualization processing in the same embodiment Sectional drawing explaining the curved state of the upper board | substrate just before bonding in the same embodiment (A) sectional view showing a state of holding the upper substrate by the vacuum suction table and (b) sectional view showing a curved state of the upper substrate by suction to the vacuum suction table in the same embodiment Sectional drawing of the bonding process of Embodiment 3 of this invention Side view of the manufacturing apparatus for explaining the operation of the roller system in the conventional example

Embodiments of the present invention will be described with reference to the drawings.
In the drawings, exaggeration and ratio are changed for easy explanation.
(Embodiment 1)
1 to 7 show Embodiment 1 of the present invention.

  Here, as shown in FIGS. 1A and 1B, a liquid crystal display module with a touch panel in which a transparent touch panel (hereinafter referred to as a touch panel) 2 is bonded to a liquid crystal display panel 1 with an ultraviolet curable resin 3 is manufactured. explain.

  A liquid crystal display panel 1 as a first panel has a structure in which liquid crystal is sealed between an array substrate 1a and a color filter substrate 1b, and an upper polarizing plate 1c and a lower polarizing plate 1d are bonded to both surfaces thereof. Although not shown, a driver integrated circuit, a flexible substrate, and the like are mounted.

The touch panel 2 as the second panel has a structure in which a transparent electrode having conductivity is disposed on a glass substrate in order to detect a position touched by a user.
Resin 3 is a colorless and transparent acrylic resin having an initial viscosity of 3500 mPa · sec. UV curing conditions, when the semi-curing is 500 mJ / cm ^2, the curing is the irradiation intensity of 1500 mJ / cm ^2. The resin 3 has an elastic property with a tensile modulus of about 0.06 MPa even after the main curing, and has a function of reducing the impact even when the liquid crystal display module receives an impact.

The upper polarizing plate 1c and the touch panel 2 of the liquid crystal display panel 1 are bonded together so that the upper polarizing plate 1c and the transparent electrode side of the touch panel 2 face each other.
For attaching the touch panel 2 to the upper polarizing plate 1c of the liquid crystal display panel 1, a slit die coater shown in FIGS. 5A and 5B and a panel sticking apparatus shown in FIG. 7A are used.

Before setting the liquid crystal display panel 1 to the panel sticking device, the resin 3 is applied to the upper polarizing plate 1c of the liquid crystal display panel 1.
Specifically, the liquid crystal display panel 1 shown in FIGS. 2A and 2B has a size of 225 mm × 145 mm and a thickness of 2.5 mm. Resin 3 is applied to the entire surface of filling region 4 on upper polarizing plate 1c. The filling region 4 is located inside the upper polarizing plate 1c, has a dimension of 218 mm × 138 mm, and a coating thickness of 0.15 mm.

  As described above, a slit die coater is used as a coating device for coating the liquid crystal display panel 1 which is one surface of the liquid crystal display panel 1 and the touch panel 2 with the resin 3 in a rectangular shape by raising the periphery from the inner coating surface 4a. It was. The slit die coater is a system in which a coating liquid is supplied to a die, the coating liquid is pressurized in the die, and the coating liquid that has passed through the slit is directly applied to the substrate. The setting of the coating thickness is determined by the slit gap, pressure, die moving speed, coating gap, and the like. Further, the size of the coating area is determined by the slit width and the moving distance of the die.

  FIG. 3 is a perspective view showing a state in which the resin 3 is coated on the liquid crystal display panel 1 by a slit die coater. The arrow A indicates the coating direction, W indicates the slit width, L indicates the moving distance of the die, and the filling region 4 is formed.

  4A is a cross-sectional view in the L direction in FIG. 3, and FIG. 4B is a cross-sectional view in the W direction in FIG. The periphery of the resin 3 applied to the filling region 4 in a rectangular shape is raised from the application surface 4a. The rise of the resin is applied with a side W1 and a side W2 having a width of 1.5 mm in FIG. 10 μm higher than the surface 4a, and in FIG. 4B, the side L1 and the side L2 are 1.5 mm wide and 25 μm higher than the coating surface 4a.

  In this way, a specific process for forming the periphery of the resin 3 applied to the entire surface of the filling region 4 of the liquid crystal display panel 1 from the application surface 4a will be described in detail with reference to FIGS. To do.

  FIG. 5A is a sectional view of a die in the slit die coater, and FIG. 5B is a front view thereof. 5A and 5B show a state in which the resin 3 is filled in the manifold 5a provided on the die 5 and the plunger 6 is inserted into the manifold 5a.

  Here, the slit gap of the slit 5b is 0.2 mm, and the gap between the liquid crystal display panel 1 and the lip 5c which is the tip of the slit 5b is 0.2 mm. When the plunger 6 is pushed down in this state, the pressure in the manifold 5a increases, and the resin 3 is discharged from the lip 5c of the slit 5b and contacts the surface of the liquid crystal display panel 1.

  In general, at the start of coating, it is usual to provide a waiting time of about 1 second in order for the discharged resin to come into contact with the object to be coated uniformly and linearly. Set to 2 seconds long. As a result, a large amount of resin 3 is discharged at the coating start point, resulting in swell.

  Thereafter, the die 5 was moved at a speed of 25 mm / second, and waited for 1 second at the coating end point to increase the discharge amount. Then, the plunger 6 was stopped from being pushed down and the die 5 was raised. As a result, as shown in FIG. 4A, W1 corresponding to the coating start point and W2 corresponding to the coating end point rise from the application surface 4a.

  In coating with a normal slit die coater, the waiting time is minimized at the coating start point and the waiting time is not provided at the coating end point to reduce the swelling, but conversely, the resin 3 It is a translation that made it rise.

Next, a process of forming the swells of the side L1 and the side L2 parallel to the coating direction A shown in FIG.
In the front view of the die 5 in the slit die coater of FIG. 5B, the slit end face 5d is set to 90 ° with respect to the lip 5c. On the other hand, the comparative example shown in FIG. 5C is a normal die, and is configured at an angle that widens the slit end face 5d outward. This is done in order to prevent the pressure distribution of the coating liquid in the slit 5b from becoming suddenly higher near the slit end face than near the center of the slit 5b. This is because the pressure is equalized and the discharge amount in the entire slit width W is made uniform.

  In FIG. 5B, by setting the slit end face 5d to 90 ° with respect to the lip 5c, the pressure distribution of the resin 3 in the slit 5b is caused by the reaction force due to the slit end face 5d as compared with the vicinity of the center of the slit 5b. As a result, the height suddenly increases in the vicinity of the slit end face 5d.

As a result, a large amount of the resin 3 is discharged in the vicinity of the slit end surface 5d, and the side L1 and the side L2 are raised from the application surface 4a as shown in FIG. 4B.
Note that the angle of the slit end face 5d with respect to the lip 5c is not limited to 90 °, and it is 90 ° depending on properties such as the viscosity and wettability of the coating liquid, the pressure in the manifold, and the coating conditions such as the coating speed. Determined in the vicinity.

In order to make the side L1 and the side L2 rise from the application surface 4a, it is also effective to widen the slit gap of the slit 5b in the vicinity of the slit end surface 5d.
In this way, when the entire surface of the UV curable resin 3 is completely applied to the filling region 4 of the liquid crystal display panel 1, UV light is then applied only to the side portion having a width of 1.5 mm along the entire circumference of the applied UV curable resin 3. The resin 3 was semi-cured by irradiation. As the first curing device 13 that irradiates the surroundings with ultraviolet rays, a method of scanning spot light from the light source 14, a method of using the light source 14 and the mask 15, or a method of line irradiation can be applied.

  Next, the surface of the liquid crystal display panel 1 and the touch panel 2 face each other, and the touch panel 2 extends along the side L1 and the side L2 having higher bulges around the resin 3 applied to the entire filling region 4 of the liquid crystal display panel 1. Laminate to the outside.

The panel sticking apparatus 7 shown to Fig.7 (a) is comprised as follows.
The lower suction stand 7a on which the liquid crystal display panel 1 is placed has a vacuum suction system A (not shown) and includes a post 7b. The upper suction stand 7c facing the lower suction stand 7a is slidable on the post 7b via a linear bush 7f, and is lifted in parallel in the vertical direction by a stepping motor (not shown) connected to a ball screw 7g as a lifting device. The upper suction stand 7c can accurately set the raising / lowering speed and positioning the raising / lowering stop. Further, a vacuum suction system B (not shown) is provided on the lower surface of the upper suction table 7c.

  A porous vacuum suction table 7d is set on the lower surface of the upper suction table 7c. The vacuum suction table 7d has a suction surface 7e formed in an arc shape, and the arc has a height of 0.2 mm with respect to a chord length of 245 mm.

The lower sticking stand 7a of the panel sticking device 7 is provided with a stowable positioning block 7h shown in FIG.
Before the liquid crystal display panel 1 is placed on the lower suction stand 7a of the panel sticking device as shown in FIG. 7A, the positioning block 7h is moved from the lower suction stand 7a as shown in FIG. 7B. Is placed in a protruding state, and the touch panel 2 with the bonding surface down is placed on the positioning block 7h.

  The size of the touch panel 2 is 245 mm × 172 mm, and the glass is 0.7 mm in thickness. In addition, a frame-shaped black printed matter is formed in the outer range of the display area slightly smaller than the filling area 4 of the liquid crystal display panel 1.

  Then, as shown in FIG. 7C, the vacuum suction stand 7 d is lowered toward the touch panel 2. After the vacuum suction table 7d is lowered to the vicinity of the touch panel 2, here, the touch panel 2 is deformed by low-speed movement and is lowered to a position substantially along the arc of the vacuum suction table 7d and stopped. In this state, the release device 16 is switched so as to draw a vacuum from the vacuum suction system B connected to the vacuum suction table 7d, and the touch panel 2 is sucked and held on the vacuum suction table 7d.

  In FIG. 7D, after the vacuum suction table 7d holding the touch panel 2 rises to the bonding standby position, the liquid crystal display panel 1 coated with the resin 3 is sucked and held by the vacuum suction system B on the lower suction table 7a. It is in a state.

  Next, as shown in FIG. 7 (e), after the vacuum suction stand 7 d that sucks and holds the touch panel 2 is lowered and a part of the touch panel 2 comes into contact with the application surface 4 a of the resin 3, the touch panel 2 is further moved. It is pressed against the resin 3 by the vacuum suction table 7d.

  FIG. 7 (f) shows a state where the vacuum from the vacuum suction system B connected to the vacuum suction table 7 d holding the touch panel 2 is released. The touch panel 2 can be bonded by being released from the curvature maintained by the vacuum suction table 7d and restored to a flat plate state. Thereafter, the vacuum suction stand 7d was raised.

Details of FIG. 7E and FIG. 7F will be described with reference to FIG.
As shown in FIG. 6A, the upper polarizing plate 1c of the liquid crystal display panel 1 is coated with the resin 3 such that the side L1 and the side L2 are 25 μm higher than the coating surface 4a. The touch panel 2 faces the resin 3 and is curved so that the center or substantially the center approaches the liquid crystal display panel 1. The top of the touch panel 2 is in contact with the center of the side L1 and the side L2 of the resin 3. Yes. The curvature of the touch panel 2 is 0.2 mm with respect to the length of 245 mm.

  FIG. 6B shows a state in which the touch panel 2 is lowered and brought into contact with the coating surface 4a and then pushed in by 0.02 mm. At this time, since the side L1 and the side L2 of the resin 3 are in a semi-cured state, the resin 3 is easily elastically deformed, and does not prevent the curved top portion of the touch panel 2 from being in contact with and pushed into the application surface 4a. Furthermore, when this state is maintained, the contact between the touch panel 2 and the coating surface 4a expands outward due to the surface tension of the resin 3.

  Next, as shown in FIG. 7F, when the suction holding of the touch panel 2 by the vacuum suction table 7d is released and the curvature of the touch panel 2 is released, the touch panel 2 is gradually restored to a flat shape by its own elasticity. As shown in FIG. 6C, the contact between the application surface 4a and the touch panel 2 reaches the end of the application surface 4a.

  Thus, since bonding is performed while expanding the contact area from the center of the filling area 4 toward the end, the gap between the touch panel 2 and the side W1 and the side W2, which are located at both ends, and has a lower swell Since it is discharged more, bubbles do not remain. Further, since the adhesive force between the resin 3 and the touch panel 2 bonded without bubbles is larger than the elastic forces of the semi-cured sides L1 and L2 and sides W1 and W2, a vacuum is applied from the solid line position to the virtual line position in FIG. Even if the suction table 7d is lifted and the pressing of the touch panel 2 by the vacuum suction table 7d is released, the bonded state of the liquid crystal display panel 1 and the touch panel 2 can be maintained.

  Since the touch panel 2 is bonded after the resin 3 is semi-cured, the touch panel 2 is bonded while being pressed along the side L1 and the side L2 where the swell is high, so the liquid crystal in a state where the bonding is completed A gap between the display panel 1 and the touch panel 2 can be created to a specified value. When the bonding is advanced in order from the center while expanding the adhesion region, the air is surely discharged from the gaps between the side W1, the side W2, and the touch panel 2 where the swell is low.

When the process of FIG. 7 (f) is completed, as shown in FIG. 6 (c), ultraviolet rays are irradiated from the side of the touch panel 2 by the second curing device 17 at an irradiation intensity of 1500 mJ / cm ² , and the resin 3 Was fully cured. Since the resin used is single, there is no expression of the bonding interface even after the main curing, and the problem of the conventional bonding interface between the dam resin and the filling ultraviolet curable resin can be solved.

Note that the second curing device 17 and the first curing device 13 may be configured to share a single light source.
In this way, the bonding can be performed only by bringing the touch panel 2 into close contact with the resin 3 applied on the entire surface. Therefore, it is not necessary to spread the resin to the filling area as in the conventional flip method or roller method, so that the waiting time until the resin reaches the dam becomes unnecessary, and in addition to the bonding, Since the resin flow is slight and the periphery of the resin 3 applied on the entire surface is semi-cured, the resin flow is suppressed, and the resin does not protrude outside the filling region. Furthermore, since the bonding is performed from the center of the pair of sides having higher swell toward the end in the outer direction, the bonding time can be further shortened.

  In addition, since the adhesion is expanded on the entire surface of the filling region by releasing the deformation of the curved shape after bringing the panel deformed into the curved shape into contact with the vicinity of the center of the filling region where the resin is applied, The touch panel 2 can be bent and held by the vacuum suction table 7d, and a good attachment state can be realized by a simple device that simply releases the holding.

  This realizes a low-cost and highly reliable display device that does not cause problems such as the resin sticking out of the filling area or remaining bubbles in the panel even if bonded in the air without providing a dam. it can.

  In this embodiment, the entire surface of the liquid crystal display panel 1 is coated with the resin 3, the touch panel 2 not coated with the resin 3 is deformed into a curved shape, and the touch panel 2 is bonded to the liquid crystal display panel 1 via the resin 3. However, when the liquid crystal display panel 1 is flexible, the sides L1, L2, W1, and W2 are applied on the touch panel 2 side in the same manner as when the resin 3 is applied to the entire surface of the liquid crystal display panel 1. It is also possible to apply the resin 3 over the entire surface, and deform the liquid crystal display panel 1 to which the resin 3 is not applied into a curved shape, and attach the liquid crystal display panel 1 to the touch panel 2 via the resin 3. it can. Furthermore, the liquid crystal display panel 1 can be similarly implemented even if it is another flat display panel such as a plasma display or an organic EL panel.

(Embodiment 2)
8 to 13 show a second embodiment of the present invention.
In the second embodiment, a case where a protective panel is bonded to an organic EL device will be described.

8A and 8B show a single organic EL device completed.
The organic EL device 8 applies a phenomenon in which the organic substance itself emits light when a voltage is applied to the organic substance. The organic EL layer is formed by stacking a thin film on the lower substrate 8a with the organic substance sandwiched between two electrodes. 8b is formed, and the organic EL layer 8b is covered with the upper substrate 8c through the resin 8d in order to protect the organic EL layer 8b from humidity and impact.

  The lower substrate 8a is made of glass having a thickness of 0.7 mm and is a square having a size of 100 mm. The size of the organic EL layer 8b is a square of 80 mm and the film thickness is several microns. Electrodes (not shown) are disposed on the lower substrate 8a. The upper substrate 8c is made of glass with a plate thickness of 0.5 mm and is a square with a size of 90 mm. Further, the resin 8d is an ultraviolet curable resin to which moisture-proof performance is added and has a viscosity of 6000 mPa · sec. The gap between the lower substrate 8a and the upper substrate 8c is 0.05 mm and is filled with a resin 8d.

  In the manufacture of this organic EL device, a large number of organic EL layers 8b are taken on a single lower substrate, and the upper substrate is bonded to this, and then separated into individual pieces. Complete.

  Specifically, as shown in FIGS. 9A and 9B, the large lower substrate 9a as the first panel is a glass plate having a thickness of 0.7 mm and a size of 470 mm × 370 mm. An organic EL layer 8b arranged in 3 × 4 rows is formed on the lower substrate 9a, and a resin 8d is applied so as to cover the organic EL layer 8b.

  Application was performed by using the die 5 shown in FIGS. 5A and 5B described in the first embodiment and changing the slit width of the slit 5b to 90 mm and the slit gap to 0.05 mm. In addition, the distance between the lip 5c and the lower substrate 9a was 0.07 mm, and coating was performed in each row in the direction of arrow B in FIG. The four organic EL layers 8b arranged in one row were repeatedly applied intermittently with respect to the application lengths P1-P2, P3-P4, P5-P6, and P7-P8 in the arrow B direction. As in the case shown in FIG. 4A described in the first embodiment, the application state of the individual resins 8d applied in this way is set to W1 corresponding to the application start point and the application end point. The corresponding W2 rises from the coating surface 4a.

  Further, in the side parallel to the arrow direction, as in the case shown in FIG. 4B described in the first embodiment, the side L1 and the side L2 are raised from the application surface 4a. The swell of the applied resin 8d was such that side W1 and side W2 were 1.5 mm wide and 7 μm higher than the application surface 4a, and side L1 and side L2 were 1.5 mm wide and 15 μm higher than the application surface 4a.

  Although an example in which the intermittent application is performed one by one in three times has been described, if the die 10 shown in FIG. 10 is used, intermittent application can be performed simultaneously in three lines. The die 10 is basically the same as the die structure shown in FIGS. 5A and 5B described in the first embodiment, but in the die 10, the slit width is extended to a length that allows three rows to be applied at the same time. The difference is that the slit width is divided into three by the plate 10a.

After the resin 8d was applied to the lower substrate 9a in this way, the resin 8d was semi-cured by irradiating ultraviolet rays to only the side portion having a width of 1.5 mm around the entire circumference of the resin 8d.
Next, a process of bonding the lower substrate 9a and the large upper substrate 9b as the second panel as shown in FIG. 11 will be described.

  In the bonding step, as shown in FIG. 12, the upper substrate 9b is disposed facing the lower substrate 9a coated with the resin 8d. The large-size substrate 9b has a size of 470 mm × 370 mm and a thickness of 0.5 mm.

  The upper substrate 9b is curved corresponding to the position of the organic EL layer 8b on the lower substrate 9a as shown in FIGS. Specifically, compared with the vicinity of the center of each organic EL layer 8b on the lower substrate 9a, the portion corresponding to the vicinity of both ends of each organic EL layer 8b is curved into a waveform so as to be far from the lower substrate 9a. . For this purpose, a spacer 12 having a width of 7 mm and a depth length of 350 mm and a thickness of 0.1 mm is arranged between the upper substrate 9b and the large-sized and porous vacuum suction table 11 and the upper substrate 9b. As the spacer 12, it is desirable to use a material having air permeability such as paper, cloth and a porous resin sheet in a strip shape.

  Next, by evacuating from the vacuum suction system B communicating with the vacuum suction table 11, the upper substrate 9b is deformed into a plurality of mountain-shaped curved shapes as shown in FIG. Retained. Thus, since the upper substrate 9b is more likely to bend as the substrate has a smaller plate thickness and a larger area, it is possible to form a curve at a plurality of locations. The bending amount is 0.1 mm with respect to 100 mm.

  Thus, the upper substrate 9b sucked and held on the vacuum suction table 11 is lowered toward the lower substrate 9a. After the upper substrate 9b comes into contact with the application surface of the resin 8d, the contact area of the upper substrate 9b with the lower substrate 9a is expanded by further pressing the upper substrate 9b by 0.02 mm.

  Thereafter, the upper substrate 9b is gradually restored to a flat shape by its own elasticity by releasing the curvature of the upper substrate 9b by the vacuum suction table 11, and the upper substrate 9b is applied to the entire area where the resin 8d is applied as shown in FIG. To reach.

Thereafter, the entire surface of the applied resin 8d was irradiated with ultraviolet rays to be fully cured. As a method of separating from a large size, it is divided into pieces by scribe break or dicing.
As described above, since the bonding is performed while the contact area is enlarged from the center of the coating area toward the end, air is discharged from the gap between the lower side located at both ends and the lower substrate 9b. , No bubbles remain. This is performed simultaneously at all the application locations of the plurality of resins 8d arranged on the upper substrate 9b.

  In addition, the upper substrate 9b, which will later become the upper substrate 8c, can be bonded to the plurality of organic EL layers 8b disposed on the lower substrate 9a, and it is not necessary to spread the resin in the filling region. Since the accompanying resin flow is slight and the periphery of the resin 8d applied on the entire surface is semi-cured, the flow of the resin 8d is suppressed and the resin does not protrude outside the filling region. Furthermore, since it sticks toward the edge part of an outer direction from the center of a pair of side with a higher swell, it sticks together while expelling air, Therefore A bubble does not remain.

  In this way, a highly reliable display device that does not cause problems such as the resin sticking out of the filling area and remaining bubbles in the panel even if bonded in the air without providing a dam is provided at low cost. It can be provided and is suitable for manufacturing applications such as surface emitting devices typified by organic EL lighting.

(Embodiment 3)
FIG. 14 shows a third embodiment of the present invention.
In each of the embodiments described above, the touch panel 2 or the liquid crystal display panel 1 is deformed into a curved shape and then bonded together via the resin 3. However, as shown in FIG. 14, the size of the touch panel 2 is as shown in FIG. If the size is smaller than that of the case, the touch panel 2 or the liquid crystal display panel 1 can be satisfactorily bonded to each other without deforming the touch panel 2 or the liquid crystal display panel 1 into a curved shape.

  In FIG. 14A, as in the case of the first embodiment, the resin 3 is placed on the liquid crystal display panel 1, the periphery on one side L1 and L2 facing each other, and the periphery on the other pair of sides W1 and W2, respectively. The resin 3 is swelled from the inner application surface 4a of the resin 3 and the height of the sides L1 and L2 is higher than the sides W1 and W2, and the periphery of the resin 3 applied on the entire surface is half-coated by the first curing device 13. Harden.

  In FIG. 14B, the flat touch panel 2 that is not curved and deformed is brought close to the liquid crystal display panel 1 and only a part of the resin 3 on the sides L1 and L2 having higher bulges is elastically deformed. In a state where the touch panel 2 is tilted, the resin 3 on one side W1 having a lower height is further pressed against the liquid crystal display panel 1 to elastically deform, and one end of the touch panel 2 is pressed against the coating surface 4a.

  Next, the support of the other end of the touch panel 2 is released from the state in which the touch panel 2 is pressed against the one side W1 of the resin 3, and the inclination of the flat touch panel 2 that is not curved is gradually reduced. Then, the touch panel 2 is brought into close contact with the liquid crystal display panel 1 through the resin 3 along the side L1 and L2 with higher elevation toward the other side W2 with lower elevation.

  Thus, the adhesive force between the resin 3 and the touch panel 2 bonded together without bubbles is strong, and the bonded state can be maintained. In this state, as shown in FIG. 14C, the resin 3 is completely cured by the second curing device 17 to complete the bonding.

  In the third embodiment, the liquid crystal display panel 1 is coated with the resin 3 and the touch panel 2 is bonded. However, the flat liquid crystal display panel 1 that is not curved and deformed to the touch panel 2 coated with the resin 3. Similarly, both of them can be pasted together by gradually reducing the inclination of.

  As described above, the first panel or the second panel provided in the first embodiment as the panel pasting apparatus is used when both panels are pasted well without changing one panel into a curved shape. A deforming device that deforms one of the opposing surfaces into a curved shape and a release device that releases the curved deformation are not required.

  Furthermore, in the panel sticking device of the first embodiment, the facing device that makes the liquid crystal display panel 1 and the touch panel 2 face each other, and the distance between the liquid crystal display panel 1 and the touch panel 2 are shortened in parallel to closely contact each other through the resin 3. However, in the facing device in the case of Embodiment 3 in which one panel is bonded without being deformed into a curved shape, one end of the touch panel 2 is closer to the liquid crystal display panel 1 than the other end. It is comprised so that it may face and support in the state inclined to. Further, the lifting device in the case of the third embodiment in which one panel is bonded without being deformed into a curved shape reduces the distance between the one end of the touch panel 2 supported in an inclined state and the liquid crystal display panel 1. 2 is in close contact with the liquid crystal display panel 1 through the resin 3.

  Furthermore, in the panel sticking device of the first embodiment, the release device for releasing the deformation of the curved shape is provided. However, in the case of the third embodiment in which one panel is bonded without being deformed to the curved shape. The release device is configured to release the support of the other end of the touch panel 2 in a state where the one end of the touch panel 2 is pressed against the liquid crystal display panel 1 via the resin 3.

  INDUSTRIAL APPLICABILITY The present invention is suitable for manufacturing applications such as a surface emitting device represented by organic EL lighting in addition to the display field such as a liquid crystal display device and an organic EL display device.

1 Liquid crystal display panel (first panel)
2 Touch panel (second panel)
3 Resin 4 Filling area 4a Application surface 5 Die 5a Manifold 5b Slit 5c Lip 5d Slit end surface 6 Plunger 7 Panel sticking device 7a Lower suction stand 7b Post 7c Upper suction stand 7d Vacuum suction stand 7e Adsorption face 7f Linear bush 7g Ball screw 8 Organic EL device 8a Lower substrate 8b Organic EL layer 8c Upper substrate 8d Resin 9a Lower substrate (first panel)
9b Upper substrate (second panel)
10 Die 11 Vacuum Suction Stand 12 Spacer 13 First Curing Device 14 Light Source 15 Mask 16 Release Device 17 Second Curing Device

Claims (9)

When attaching the second panel to the first panel with resin,
The surface of the first panel and one surface of the opposing surface of the second panel are rectangular with the surroundings raised from the inside so that the height of the other pair of sides orthogonal to the opposing pair of sides is different Apply the resin to
Semi-curing the periphery of the applied resin,
A panel sticking method in which the first panel and the second panel are brought into contact with each other and brought into close contact with each other, and then the entire resin is fully cured. The panel sticking method according to claim 1, wherein the surrounding bulge in the resin is formed simultaneously with the application of the resin to the surface of the first panel. The surface of the first panel and the second panel face each other, and the second panel is gradually moved outward along the pair of sides of the coated resin where the surrounding bulge is higher. The panel sticking method according to claim 1, wherein the panel is stuck to the panel. The surface of the first panel and the second panel are faced to each other, and the second panel is placed in the center of the second panel or substantially along the pair of sides that are higher in the periphery of the applied resin. The panel sticking method according to claim 1, wherein the panel is gradually brought into close contact with the first panel from the center toward the outside. The panel sticking method according to claim 1, wherein the first panel is a flat display panel, the second panel is a transparent touch panel, and the resin is applied to the flat display panel. 2. The first panel is a lower substrate on which an organic EL layer is formed, and the second panel is an upper substrate that protects the organic EL layer, and the resin is applied to the lower substrate. Panel pasting method. Raise the periphery from the inside so that the height of the other pair of sides orthogonal to the opposite pair of sides is raised on one surface of the first panel and the second panel that are bonded together. An applicator for applying to the shape;
A first curing device for semi-curing the periphery of the applied resin;
A facing device for facing the first panel and the second panel;
A deformation device that deforms one surface of the opposing surface of the first panel or the second panel into a curved shape;
A lifting device for reducing the distance between the first panel and the second panel facing each other in parallel and closely contacting the resin through the resin;
A release device for releasing the deformation of the curved shape;
The panel sticking apparatus which has a 2nd hardening apparatus which carries out the main hardening of all the said resin interposed between the said 1st panel and the said 2nd panel. The panel according to claim 7, wherein the coating device is a slit die coater, and the slit end surface of the slit die coater is disposed so as to be 90 ° or in the vicinity thereof with respect to the lip of the slit die coater. Pasting device. Resin by raising the periphery from the inside so that the height of the other pair of sides orthogonal to the pair of opposite sides is different in the filling region of one surface of the first panel and the second panel to be bonded to each other An applicator for applying a rectangular shape;
A first curing device for semi-curing the periphery of the applied resin;
A facing device that supports and faces one end of the second panel so as to be closer to the first panel than the other end; and
An elevating device for reducing the distance between the one end of the second panel supported in an inclined state and the first panel and bringing the second panel into close contact with the resin;
A release device for releasing support of the other end of the second panel in a state where the one end of the second panel supported in an inclined state is pressed against the first panel via the resin;
The panel sticking apparatus which has a 2nd hardening apparatus which carries out the main hardening of all the said resin interposed between the said 1st panel and the said 2nd panel.

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