Laminating equipment

Abstract

The present disclosure is about a bonding device, which includes a carrier film and a clamping fixture. The flexible substrate is attached to the carrier film, and the carrier film is pulled down by the clamping fixture so that the carrier film is tightly attached to the support surface, and the flexible bonding pad is pushed to move in a positive direction perpendicular to the bonding surface as a whole, so as to achieve a one-time bonding of the curved cover plate and the flexible substrate. A circle of channels is provided in the flexible bonding pad, and the cross-section of the flow section of the channel gradually decreases from the center to the edge of the flexible bonding pad. A flowing medium flows in the channel. By applying pressure to the wall of the flow section, when the flowing medium passes through different positions of different flow sections, the deformation of the flexible bonding pad on the bonding curved surface is greater than the deformation of the bonding plane, and a secondary bonding is achieved on the bonding surface near the bonding curved surface, which reduces the possibility of poor bonding and improves the bonding effect of the flexible substrate and the curved cover plate.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a bonding device. Background Art

[0002] At present, OLED displays have been widely used in various electronic products, and with the development of curved screens, large curvature covers have become a new trend, which puts higher requirements on the full bonding method of curved cover plates and flexible display panels.

[0003] In the existing curved surface bonding process, if the bonding pressure is too high, dark spots will easily appear on the curved surface area of ​​the curved screen, or even the cover plate will break; if the bonding pressure is too low or the force is uneven, bubbles or wrinkles will appear. Therefore, the existing bonding device is more likely to have poor bonding and the bonding effect is poor.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present disclosure is to overcome the problem that dark spots, bubbles or wrinkles are very likely to appear in the curved area of ​​the curved screen, and the present disclosure provides a bonding device.

[0006] According to one aspect of the present disclosure, there is provided a bonding device, including a laminating mechanism, a supporting mechanism and a bearing mechanism, wherein the laminating mechanism includes a laminating mold, the laminating mold has a laminating surface, and the laminating surface is used to match the shape of the curved cover plate; the supporting mechanism includes a flexible laminating pad, and the flexible laminating pad has a supporting surface opposite to the laminating surface; the bearing mechanism includes a bearing film and a clamping fixture, the bearing film is located between the laminating surface and the supporting surface, the side of the bearing film facing the laminating surface is used to attach the flexible substrate, and the clamping fixture is clamped on the edge of the bearing film; a circle of channels is provided in the flexible laminating pad, the channel includes an inlet, a flow section and an outlet connected in sequence, the inlet is close to the center of the flexible laminating pad, the outlet is close to the edge of the flexible laminating pad, and the cross-section of the flow section gradually decreases from the center to the edge of the flexible laminating pad, and a flowing medium flows in the channel.

[0007] In one embodiment of the present disclosure, the thickness of the portion between the flow passage section and the supporting surface gradually increases.

[0008] In one embodiment of the present disclosure, the extension direction of the flow section is parallel to the supporting surface, the flow section is connected to the inlet through a first corner, the flow section is connected to the outlet through a second corner, and the angle between the outlet and the flow section is smaller than the angle between the inlet and the flow section.

[0009] In one embodiment of the present disclosure, the angle between the outlet and the flow section is less than 90 degrees.

[0010] In one embodiment of the present disclosure, the angle between the outlet and the flow section is 50-90 degrees.

[0011] In one embodiment of the present disclosure, the sum of the radius of curvature of the flexible fitting pad, the thickness of the carrier film, and the thickness of the flexible substrate is less than or equal to the radius of curvature of the concave surface of the curved cover plate.

[0012] In one embodiment of the present disclosure, the width of the planar area of ​​the flexible conformable pad is: H P =H G -2ΔH, where ΔH is the plane fitting gap, and the width of the plane area of ​​the curved cover is H G ; Radius R of the bending area of ​​the flexible conformable pad P =R G -T G -T F -T C -σ, where σ is the surface fitting gap, R G is the inner radius of the curved area of ​​the curved cover plate, T G is the thickness of the curved cover plate, T F is the thickness of the flexible substrate, T C is the thickness of the carrier film.

[0013] In one embodiment of the present disclosure, the pressing surface is provided with a plurality of vacuum adsorption holes, and the plurality of vacuum adsorption holes are evenly arranged on the pressing surface.

[0014] In one embodiment of the present disclosure, the clamping fixture includes a plurality of pairs of clamping units, each pair of clamping units includes two clamping units, and the two clamping units are respectively used to clamp two opposite sides of the carrier film.

[0015] In one embodiment of the present disclosure, the clamping unit includes a first clamping portion and a second clamping portion, the first clamping portion and the second clamping portion are parallel to the carrier film, and the carrier film is clamped between the first clamping portion and the second clamping portion.

[0016] The bonding device disclosed in the present invention includes a carrier film and a clamping fixture. The flexible substrate is attached to the carrier film. The carrier film is pulled down by the clamping fixture so that the carrier film is tightly attached to the support surface, and the flexible bonding pad is pushed to move in a positive direction perpendicular to the bonding surface as a whole, so as to achieve a one-time bonding of the curved cover plate and the flexible substrate. A circle of channels is provided in the flexible bonding pad, and the cross-section of the flow section of the channel gradually decreases from the center to the edge of the flexible bonding pad. A flowing medium flows in the channel. By applying pressure to the wall of the flow section, when the flowing medium passes through different positions of different flow sections, the deformation of the flexible bonding pad on the bonding curved surface is greater than the deformation of the bonding plane, and a secondary bonding is achieved on the bonding surface near the bonding curved surface, which reduces the possibility of poor bonding and improves the bonding effect of the flexible substrate and the curved cover plate.

[0017] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0019] Figure 1 It is a three-dimensional structural diagram of the bonding device involved in the embodiment of the present disclosure.

[0020] Figure 2 It is a front schematic diagram of the bonding device involved in the embodiment of the present disclosure.

[0021] Figure 3 It is a cross-sectional view of the bonding process of the four-curved display panel involved in the embodiment of the present disclosure.

[0022] Figure 4 It is a three-dimensional axonometric diagram of the flexible fitting pad of the four-curved display panel involved in the embodiment of the present disclosure.

[0023] Figure 5 It is a top view of the flexible bonding pad 22 of the four-curved display panel involved in the embodiment of the present disclosure.

[0024] Figure 6 It is a cross-sectional view of the bonding process of the hyperbolic display panel involved in the embodiment of the present disclosure.

[0025] Figure 7 It is a schematic diagram of the details of the bonding between the flexible substrate and the curved cover plate in the four-curved display panel involved in the embodiment of the present disclosure.

[0026] Figure 8This is a diagram of the internal structure of the flexible bonding pad of the four-curved display panel involved in the embodiment of the present disclosure.

[0027] Fig. 9 It is a schematic cross-sectional view along the second direction of the flexible bonding pad of the four-curved display panel involved in the embodiment of the present disclosure.

[0028] Fig.10 The present invention is a three-dimensional simulation cloud diagram of the deformation of the flexible bonding pad of the four-curved display panel involved in the prior art.

[0029] Fig.11 The cross-sectional deformation cloud diagram of the lamination deformation of the flexible lamination pad of the four-curved display panel involved in the prior art.

[0030] Fig.12 This is a cross-sectional deformation cloud diagram of the lamination deformation of the flexible lamination pad of the four-curved display panel involved in the embodiment of the present disclosure.

[0031] Fig.13 The cross-sectional overall stress cloud diagram of the deformation of the flexible bonding pad of the four-curved display panel involved in the prior art.

[0032] Fig.14 This is a cross-sectional overall stress cloud diagram of the deformation of the flexible bonding pad of the four-curved display panel involved in the embodiment of the present disclosure.

[0033] In the figure: 1-pressing mechanism, 11-pressing mold, 111-pressing surface, 112-vacuum adsorption hole, 2-supporting mechanism, 21-supporting platform, 22-flexible bonding pad, 221-channel, 2211-inlet, 2212-outlet, 2213-flow section, 2214-first corner, 2215-second corner, 222-supporting surface, 2221-bonding plane, 2222-bonding curved surface, 3-carrying mechanism, 31-carrying film, 32-clamping unit, 321-first clamping part, 322-second clamping part, 4-curved cover plate, 41-planar area, 42-curved area, 5-flexible substrate. DETAILED DESCRIPTION

[0034] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0035] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of the illustration to another component, these terms are used in this specification only for convenience, such as according to the orientation of the examples described in the drawings. It is understood that if the device of the illustration is turned upside down, the component described as "upper" will become the component "lower". When a structure is "on" other structures, it may mean that the structure is formed integrally on the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.

[0036] The terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express an open-ended inclusive meaning and mean that additional elements / components / etc. may exist in addition to the listed elements / components / etc.; the terms "first", "second" and "third" etc. are used merely as labels and are not intended to limit the quantity of their objects.

[0037] At present, after the preparation of the flexible substrate is completed, a protective cover plate needs to be attached to the outside of the flexible substrate to protect the flexible substrate. In order to realize the 3D curved display of the flexible panel, the edge of the flexible screen is usually set to an arc surface, so that the image in its edge area can also be displayed normally during display. Therefore, the edge end surface of the protective cover plate is also usually set to an arc surface to form a curved cover plate that matches the flexible substrate with a curved surface. In the present invention, "matching" means that the shape is roughly the same. In the process of bonding the flexible substrate and the curved cover plate, the vacuum bonding process of the four-curved flexible screen is the most difficult.

[0038] At present, in the laminating process of flexible screens, the curved cover plate is fixed by vacuum adsorption of a pressing mold, and the flexible screen is tightly attached to the supporting surface of the flexible laminating pad under the action of the carrier film and the clamping mechanism. In the vacuum chamber, the flexible laminating pad presses the flexible substrate to the inner side of the curved cover plate under the stabilizing action of the pushing device, so as to achieve seamless laminating of the flexible substrate and the curved cover plate. The following defects will mainly occur in the existing curved laminating process: if the laminating pressure is too large, dark spots will easily appear in the curved area of ​​the flexible screen, and even the cover plate will break; if the laminating pressure is too small or the force is uneven, bubbles or wrinkles will occur. Especially for the bending edges and bending corners of the four-curved flexible screen, poor laminating phenomena such as bubbles and wrinkles are quite serious.

[0039] Based on this, the present disclosure provides a bonding device. Figures 1 to 14As shown, the laminating device includes a laminating mechanism 1, a supporting mechanism 2 and a carrying mechanism 3. The laminating mechanism 1 includes a laminating mold 11, and the laminating mold 11 has a laminating surface 111, and the laminating surface 111 is used to match the shape of the curved cover plate 4; the supporting mechanism 2 includes a flexible laminating pad 22, and the flexible laminating pad 22 has a supporting surface 222 opposite to the laminating surface 111; the carrying mechanism 3 includes a carrying film 31 and a clamping fixture, and the carrying film 31 is located between the laminating surface 111 and the supporting surface 222, and the carrying film 31 faces the side of the laminating surface 111 Used to attach the flexible substrate 5, the clamping fixture is clamped on the edge of the carrier film 31; a circle of channels 221 is provided in the flexible bonding pad 22, and the channel 221 includes an inlet 2211, a flow section 2213 and an outlet 2212 which are connected in sequence, the inlet 2211 is close to the center of the flexible bonding pad 22, and the outlet 2212 is close to the edge of the flexible bonding pad 22. From the center to the edge of the flexible bonding pad 22, the cross-section of the flow section 2213 gradually decreases from the center to the edge of the flexible bonding pad 22, and a flowing medium flows in the channel 221.

[0040] The flexible substrate 5 is attached to the carrier film 31, and the carrier film 31 is pulled down by the clamping fixture so that the carrier film 31 is closely attached to the support surface 222, and the flexible bonding pad 22 is pushed to move in a positive direction perpendicular to the pressing surface 111, so that the curved cover plate 4 and the flexible substrate 5 can be pressed once. A circle of channels 221 is provided in the flexible bonding pad 22, and the cross section of the flow section 2213 of the channel 221 gradually decreases from the center to the edge of the flexible bonding pad 22. A flowing medium flows in the channel 221. By applying pressure to the wall surface of the flow section 2213, when the flowing medium passes through different positions of different flow sections 2213, the deformation of the flexible bonding pad 22 on the bonding curved surface 2222 is greater than the deformation of the bonding plane 2221, and the pressing surface 111 near the bonding curved surface 2222 is pressed twice, which reduces the possibility of poor bonding and improves the bonding effect of the flexible substrate 5 and the curved cover plate 4.

[0041] The laminating device is described in detail below with reference to specific embodiments.

[0042] like Figures 1 to 3As shown, the laminating device includes a laminating mechanism 1, a supporting mechanism 2 and a bearing mechanism 3. The laminating mechanism 1 includes a laminating mold 11. The laminating mold 11 has a laminating surface 111. The laminating surface 111 is used to laminate with the curved cover plate 4 to be fixed, and the shape of the laminating surface 111 matches the shape of the curved cover plate 4. The supporting mechanism 2 includes a supporting platform 21 and a flexible laminating pad 22. The flexible laminating pad 22 is located on the side of the supporting platform 21 facing the laminating mechanism 1. The flexible laminating pad 22 has a supporting surface 222. The shape of the supporting surface 222 matches the shape of the flexible substrate 5. The bearing mechanism 3 includes a bearing film 31 and a clamping fixture. The bearing film 31 is located between the laminating surface 111 and the supporting surface 222. The side of the bearing film 31 facing the laminating surface 111 is used to attach the flexible substrate 5. The clamping fixture is clamped on the edge of the bearing film 31.

[0043] The pressing surface 111 of the pressing mold 11 is provided with a plurality of vacuum adsorption holes 112, and negative pressure is formed in the vacuum adsorption holes 112 by suction, so as to adsorb the curved cover plate 4 that blocks the vacuum adsorption holes 112, so that the curved cover plate 4 is attached to the pressing surface 111. The plurality of vacuum adsorption holes 112 are evenly distributed on the pressing surface 111, so that each part of the curved cover plate 4 is subjected to the adsorption force, so as to better ensure the adhesion effect between the curved cover plate 4 and the pressing surface 111, and prevent the curved cover plate 4 from falling off.

[0044] In this embodiment, a plurality of vacuum adsorption holes 112 are arranged in an array on the laminating surface 111 to form an array of vacuum adsorption holes 112. The curved cover plate 4 is usually a rigid film material, and even if the adsorption forces of different vacuum adsorption holes 112 are slightly different, the curved cover plate 4 will not have wrinkles. The shape of the vacuum adsorption hole 112 array matches the curved cover plate 4. The shape of the curved cover plate 4 is rectangular, so the vacuum adsorption hole 112 array is a rectangular array. In other embodiments, when the shape of the film material to be bonded is circular, the vacuum adsorption hole 112 array can also be a circular array, which is not specifically limited here.

[0045] The support mechanism 2 includes a support platform 21 and a flexible bonding pad 22 . The flexible bonding pad 22 is located on a side of the support platform 21 facing the pressing mechanism 1 . The flexible bonding pad 22 has a support surface 222 opposite to the pressing surface 111 .

[0046] The carrying mechanism 3 includes a carrying film 31 and a clamping jig. The carrying film 31 is located between the pressing surface 111 and the supporting surface 222. The clamping jig is clamped at the edge of the carrying film 31. The side of the carrying film 31 facing the pressing surface 111 is used to attach the flexible substrate 5. When the pressing mechanism 1 moves in the direction close to the carrying film 31, it drives the curved cover plate 4 and the flexible substrate 5 to achieve gradual contact from the middle to both ends.

[0047] The clamping fixture may include multiple pairs of clamping units 32, each pair of clamping units 32 includes two clamping units 32, and the two clamping units 32 are respectively used to clamp two opposite sides of the carrier film 31, wherein several pairs of clamping units 32 are arranged at two first sides of the carrier film 31 along a first direction, and other pairs of clamping units 32 are arranged at two second sides of the carrier film 31 along a second direction, and the second direction is perpendicular to the first direction. It should be noted that the first direction is Figure 1 The x direction in the second direction is Figure 1 The clamping unit 32 may include a first clamping portion 321 and a second clamping portion 322 , the first clamping portion 321 and the second clamping portion 322 are parallel to the carrier film 31 , and the carrier film 31 is clamped between the first clamping portion 321 and the second clamping portion 322 .

[0048] In the laminating process of both the dual-curved display panel and the quad-curved display panel, the concave surface of the curved cover plate 4 is divided into a flat area 41 and a curved area 42 based on the curved cover plate 4, wherein the curved area 42 is the hardest hit area for various types of poor laminating, so the pressing mold 11 needs to cover the convex surface of the curved cover plate 4 as much as possible. The laminating direction is perpendicular to the flat area 41 of the curved cover plate 4, and the laminating relative speed can be v.

[0049] See also Figure 4 and Figure 5 , Figure 4 It is a three-dimensional axonometric view of the flexible conformable pad 22 of the four-curved display panel. Figure 5 2 is a top view of the flexible bonding pad 22 of the four-curved display panel. The portion of the support surface 222 corresponding to the plane area can be defined as the bonding plane 2221, and the portion corresponding to the curved area can be defined as the bonding curved surface 2222, and the bonding curved surface 2222 is located outside the bonding plane 2221. During the bonding process, in order to ensure that the flexible bonding pad 22 can easily enter the concave surface of the glass cover plate, the sum of the curvature radius of the flexible bonding pad 22, the thickness of the carrier film 31, and the thickness of the flexible substrate 5 is set to be less than or equal to the curvature radius of the concave surface of the glass cover plate.

[0050] Figure 6 This is a cross-sectional view of the bonding process of a hyperbolic display panel. The portion where the support surface 222 and the flat area 41 are bonded can be set as a curved surface, which is conducive to removing bubbles in the bonding area. Figure 3 This is a cross-sectional view of the bonding process of a four-curved display panel. Due to the redundancy problem of the four-curved surface, the portion where the support surface 222 and the plane area 41 are bonded can be set to a plane, otherwise wrinkles and bubbles are likely to occur. Here, a four-curved surface is used as an example for specific description.

[0051] like Figure 7As shown, in order to facilitate the flexible bonding pad 22 to better promote the flexible substrate 5 to bond with the concave surface of the curved cover plate 4 and prevent the display panel from being scratched, a plane bonding gap ΔH and a curved surface bonding gap σ are set, both of which are directly related to the material properties of the flexible bonding pad 22 and the bonding process accuracy. The width of the bonding plane 2221 of the flexible bonding pad 22 is: H P =H G -2ΔH, where ΔH is the plane fitting gap, and the width of the plane area 41 of the curved cover plate 4 is H G The radius R of the conforming surface 2222 of the flexible conforming pad 22 P =R G -T G -T F -T C -σ, where σ is the bending fit gap, R G is the inner radius of the curved area 42 of the curved cover plate 4, T G is the thickness of the curved cover plate 4, T F is the thickness of the flexible substrate 5, T C is the thickness of the carrier film 31 .

[0052] Figure 8 and Fig. 9 Schematic diagram of the internal structure of the flexible conformable pad 22. A circle of channels 221 is provided in the flexible conformable pad 22, and the entrances 2211 of the multiple channels 221 are arranged into an entrance track, and the exits 2212 of the multiple channels 221 are arranged into an exit track. The entrance track and the exit track are both parallel to the outer contour of the flexible conformable pad 22, and the entrance track is enclosed in the exit track. It should be noted that the channels 221 are symmetrically distributed about the center line of the flexible conformable pad 22 along the first direction, and the channels 221 are symmetrically distributed about the center line of the flexible conformable pad 22 along the second direction.

[0053] The channel 221 includes an inlet 2211, a flow section 2213 and an outlet 2212 which are connected in sequence, the inlet 2211 is close to the center of the flexible fit pad 22, the outlet 2212 is close to the edge of the flexible fit pad 22, the extension direction of the flow section 2213 is parallel to the support surface 222, the flow section 2213 is connected to the inlet 2211 through a first corner 2214, and the flow section 2213 is connected to the outlet 2212 through a second corner 2215. It can be understood that the orthographic projection of the first corner 2214 on the support surface 222 is close to the fit plane 2221, and the orthographic projection of the second corner 2215 on the support surface 222 is close to the fit curved surface 2222.

[0054] From the center to the edge of the flexible bonding pad 22, the cross-section of the flow section 2213 gradually decreases. A flowing medium flows in the channel 221, and the flowing medium applies pressure to the wall of the flow section 2213. When the flowing medium passes through different positions of different flow sections 2213, because the cross-sectional area of ​​the flow section 2213 gradually decreases from the bonding plane 2221 to the bonding curved surface 2222, the pressure applied by the flexible bonding pad 22 on the bonding curved surface 2222 is greater than the pressure applied by the bonding plane 2221, and a secondary pressing is performed on the pressing surface 111 near the bonding curved surface 2222. This improves the stress distribution at the bonding position of the flexible display panel.

[0055] The flowing medium will exert pressure on the wall surface of the flow section 2213, causing the flexible bonding pad 22 to deform. The thickness of the portion between the flow section 2213 and the support surface 222 gradually increases. The thickness between the portion of the flow section 2213 close to the bonding curved surface 2222 and the support surface 222 is greater than the thickness between the portion of the flow section 2213 close to the bonding plane 2221 and the support surface 222. Therefore, the deformation amount that the flexible bonding pad 22 can provide on the bonding curved surface 2222 is greater than the deformation amount that the bonding plane 2221 can provide, which can further improve the bonding between the flexible panel and the curved area 42 of the curved cover plate 4.

[0056] In order to further improve the pressure and deformation of the fitting curved surface 2222, the angle between the outlet 2212 and the flow section 2213 is set to be smaller than the angle between the inlet 2211 and the flow section 2213, which can further increase the pressure difference between the flowing medium at the first corner 2214 and the second corner 2215, so that the flexible fitting pad 22 generates greater pressure and deformation at the fitting curved surface 2222, which can further improve the fitting of the flexible panel and the curved surface area 42 of the curved cover plate 4. Usually, the angle between the inlet 2211 and the flow section 2213 is 90 degrees, so the angle between the outlet 2212 and the flow section 2213 is less than 90 degrees. In this embodiment. The angle between the outlet 2212 and the flow section 2213 is 50-90 degrees. By controlling the angle within this range, the pressure and deformation can be balanced, thereby improving the fitting effect between the flexible substrate 5 and the curved area 42 of the curved cover plate 4 while preventing excessive pressure from causing defects such as dark spots on the screen.

[0057] The channel 221 can be manufactured by 3D printing or melting mold, and the flowing medium can be gas, liquid, or even electromagnetic rheological fluid. Through the pressure of the flowing medium on the wall of the channel 221, the flexible bonding pad 22 is deformed secondary, and the flexible substrate 5 and the curved surface area 42 of the curved cover plate 4 are bonded secondary. Since the flowing medium does not directly contact the flexible display panel, the risk of contamination of the bonding surface is reduced. In order to further increase the pressure of the channel 221, the viscosity of the flowing medium can be increased, thereby changing the bonding pressure and deformation amount.

[0058] The bonding process flow is as follows: the curved cover plate 4 is firmly adsorbed on the bonding surface 111 of the bonding mold 11, and then the flexible substrate 5 is attached to the carrier film 31, and under the clamping and downward pulling action of the clamping fixture, it is tightly attached to the supporting surface 222 of the flexible bonding pad 22, and in a vacuum environment, the flexible bonding pad 22 is pushed by the moving support table 21, so that the flexible substrate 5 approaches the concave surface of the curved cover plate 4, and the bonding surface of the flexible substrate 5 and the concave surface of the curved cover plate 4 begin to be pressed once.

[0059] Under the pressure of the flowing medium on the wall of the channel 221, the part of the flexible bonding pad 22 located between the channel wall and the support surface 222 is deformed, pushing the support surface 222, especially the bonding curved surface 2222 and the curved cover plate 4 for a second pressing, thereby improving the bonding effect between the curved cover plate 4 and the flexible panel.

[0060] Fig.10 It is a simulation cloud diagram of the existing flexible bonding pad 22. Through the simulation analysis of the overall structure of the curved cover plate 4, the flexible substrate 5 and the flexible bonding pad 22, it is found that the deformation of the center position of the bonding plane 2221 and the bending edge of the bonding curved surface 2222 is small, while the deformation of the surrounding bending angles is large. This deformation result is extremely unfavorable for the removal of bubbles in the bonding area, which is consistent with the bubble defect phenomenon occurring at the center position of the bonding plane 2221 area and the bending edge of the bonding curved surface 2222.

[0061] In order to further analyze the influence of the channel 221 on the curved surface bonding of the flexible bonding pad 22, the bonding cross sections of the existing flexible bonding pad 22 and the flexible bonding pad 22 of this embodiment are respectively established for simulation comparison and analysis. The results are as follows: Figure 11-Figure 14 By comparison Fig.11 He Ru Fig.12 It was found that the deformation contour lines of the corrugated shape of the existing flexible bonding pad 22 are the fundamental reason for the occurrence of bubbles in the center position of the bonding plane 2221 and the bent edge of the bonding curved surface 2222; under the secondary action of the fluid pressure, the deformation of the bonding plane 2221 and the bent edge of the bonding area of ​​the flexible bonding pad 22 of this embodiment shows a stepped distribution, which is conducive to the discharge of bubbles.

[0062] By comparison Fig.13 and Fig.14 It is found that the maximum position of the curved surface bonding stress of the existing flexible bonding pad 22 occurs at the transition position of the curved cover plate 4 from the bonding plane 2221 to the bonding curved surface 2222, with a maximum value of 30.12Mpa; under the secondary action of the pressure of the flowing medium, the maximum stress position of the flexible bonding pad 22 of this embodiment still occurs at the transition position of the bonding plane 2221 to the bonding curved surface 2222 of the curved cover plate 4, with a maximum value of 1.86Mpa, and the bonding pressure is significantly reduced. Therefore, the flexible bonding pad 22 of the embodiment is effective in improving poor bonding bubbles and optimizing bonding pressure.

[0063] It should be noted that the flexible substrate 5 can be an OLED display substrate. It is understandable that the vehicle-mounted display module formed by the bonding device has no interference from bubbles or wrinkles, and the display quality is good. The display panel can be a small-sized mobile phone display panel or a large-sized vehicle-mounted display panel, which is not specifically limited here.

[0064] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A bonding device for bonding a curved cover plate and a flexible substrate, characterized in that: include: The pressing mechanism comprises a pressing mold, wherein the pressing mold has a pressing surface, and the pressing surface matches the shape of the curved cover plate; A support mechanism including a flexible conformable pad having a support surface opposite to the pressing surface; The bearing mechanism comprises a bearing film and a clamping fixture, wherein the bearing film is located between the pressing surface and the supporting surface, the side of the bearing film facing the pressing surface is used for attaching a flexible substrate, and the clamping fixture is clamped at the edge of the bearing film; A circle of channels is provided inside the flexible conformable pad, and the channel includes an inlet, a flow section and an outlet which are connected in sequence, the inlet is close to the center of the flexible conformable pad, the outlet is close to the edge of the flexible conformable pad, and the cross-section of the flow section gradually decreases from the center to the edge of the flexible conformable pad. A flowing medium flows in the channel, and the thickness of the portion between the flow section and the support surface gradually increases.

2. The laminating device according to claim 1, characterized in that: The extension direction of the flow section is parallel to the supporting surface, the flow section is connected to the inlet through a first corner, the flow section is connected to the outlet through a second corner, and the angle between the outlet and the flow section is smaller than the angle between the inlet and the flow section.

3. The laminating device according to claim 2, characterized in that: The angle between the outlet and the flow section is less than 90 degrees.

4. The laminating device according to claim 3, characterized in that: The angle between the outlet and the flow section is 50-90 degrees.

5. The laminating device according to claim 1, characterized in that: The sum of the curvature radius of the flexible bonding pad, the thickness of the carrier film, and the thickness of the flexible substrate is less than or equal to the curvature radius of the concave surface of the curved cover plate.

6. The laminating device according to claim 1, characterized in that: The width of the plane area of ​​the flexible conformable pad is: H P =H G -2ΔH, where ΔH is the plane fitting gap, and the width of the plane area of ​​the curved cover plate is H G ; The radius R of the bending area of ​​the flexible conformable pad P =R G -T G -T F -T C -σ, where σ is the surface fitting gap, R G is the inner radius of the curved surface area of ​​the curved cover plate, T G is the thickness of the curved cover plate, T F is the thickness of the flexible substrate, T C is the thickness of the carrier film.

7. The laminating device according to claim 1, characterized in that: The pressing surface is provided with a plurality of vacuum adsorption holes, and the plurality of vacuum adsorption holes are evenly arranged on the pressing surface.

8. The laminating device according to claim 1, characterized in that: The clamping fixture includes a plurality of pairs of clamping units, each pair of clamping units includes two clamping units, and the two clamping units are respectively used to clamp two opposite sides of the carrier film.

9. The laminating device according to claim 8, characterized in that: The clamping unit includes a first clamping portion and a second clamping portion, the first clamping portion and the second clamping portion are parallel to the carrier film, and the carrier film is clamped between the first clamping portion and the second clamping portion.

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