Sheet bonding method

Abstract

The invention discloses a sheet bonding method which is used for manufacturing a touch panel. The sheet bonding method comprises the following steps that a first sheet and a second sheet are prepared, the first sheet is provided with a first surface, an adhesive layer is formed on the first surface, the second sheet is provided with a second surface, a plurality of grooves are formed in the second surface or the adhesive layer, and the grooves extend in parallel in a certain direction, the groove is provided with an open end in the direction; and bonding the first sheet material and the second sheet material together through the adhesive layer. Wherein in the process that the first sheet and the second sheet are bonded together through the adhesive layer, air is discharged between the first sheet and the second sheet through the plurality of grooves.

Description

Technical Field

[0001] The invention relates to a sheet bonding method, in particular to a sheet bonding method used in the production of a touch panel. Background Art

[0002] In the production of touch panels, it is often necessary to bond multiple sheets together. Generally, two sheets are bonded together using adhesive. During the bonding process, adhesive is first formed on one of the sheets, and then the two sheets are bonded together using adhesive. However, the bonding area of ​​the sheets is large, so during the bonding process, air may be trapped between the sheets and the adhesive, forming air bubbles. These air bubbles may not be completely expelled by squeezing the sheets, and the remaining air bubbles become product defects. Summary of the invention

[0003] The object of the present invention is to provide a sheet bonding method for use in the manufacture of a touch panel. The sheet bonding method can utilize grooves to discharge air during the process of bonding the sheets, so as to solve the problem of residual air bubbles in the prior art.

[0004] In order to achieve the above object, the present invention provides a sheet bonding method for use in the manufacture of a touch panel, the sheet bonding method comprising the following steps:

[0005] (a) preparing a first sheet and a second sheet, wherein the first sheet has a first surface on which an adhesive layer is formed, and the second sheet has a second surface on which a plurality of first grooves are formed, wherein the plurality of first grooves extend in parallel in a first direction, and wherein the first grooves have open ends in the first direction; and

[0006] (b) bonding the first sheet material and the second sheet material together via the adhesive layer;

[0007] In the process of bonding the first sheet material and the second sheet material together via the adhesive layer, air is discharged between the first sheet material and the second sheet material via the plurality of first grooves.

[0008] As an optional technical solution, the multiple first grooves are formed on the adhesive layer, and the multiple first grooves completely penetrate the surface of the adhesive layer along the first direction; or, the multiple first grooves are formed on the adhesive layer, one group of first grooves has only one open end along the first direction, and the other group of first grooves has an open end in a direction opposite to the first direction, and the two groups of first grooves partially overlap in the vertical projection of the arrangement direction of the multiple first grooves.

[0009] As an optional technical solution, the multiple first grooves are formed on the adhesive layer, and step (a) also includes providing a release film, the release film having a plurality of protruding structures, attaching the release film to the adhesive layer and forming the multiple first grooves on the adhesive layer through the plurality of protruding structures. The sheet bonding method also includes, before step (b), removing the release film from the adhesive layer.

[0010] As an optional technical solution, the plurality of first grooves are formed on the adhesive layer, and the bottom of the first groove is the first surface.

[0011] As an optional technical solution, the first sheet material and the second sheet material are any two of a plate-shaped touch sensing component, a plate-shaped light guide structure and a cover plate.

[0012] As an optional technical solution, the first sheet material is a light guide plate, and the second sheet material is a reflective sheet.

[0013] As an optional technical solution, a printed ink layer is provided on the reflective sheet, and the plurality of first grooves are formed on the printed ink layer.

[0014] As an optional technical solution, the cross-section of the first groove is rectangular, arc-shaped or V-shaped.

[0015] As an optional technical solution, the first groove has an open end in a direction opposite to the first direction.

[0016] As an optional technical solution, in step (a), a plurality of second grooves are formed on the second surface or the adhesive layer, the plurality of second grooves extend in parallel in a second direction, the second grooves have open ends in the second direction, and the second direction is not parallel to the first direction.

[0017] The sheet bonding method provided by the present invention is used in the production of a touch panel. In the process of bonding the first sheet and the second sheet together via the adhesive layer, air is discharged between the first sheet and the second sheet via the plurality of grooves. Thus, when the first sheet and the second sheet are relatively pressed together, the air between the two can flow along the plurality of grooves and be discharged via the open ends of the plurality of grooves, so the sheet bonding method can effectively suppress the generation of bubbles.

[0018] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments, but is not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flow chart of the sheet bonding method according to the first embodiment of the present invention;

[0020] Figure 2 A side view of a first sheet and a second sheet prepared for the sheet bonding method of the present invention;

[0021] Figure 3 for Figure 2 A top view of the adhesive layer on the first sheet;

[0022] Figure 4 A side view of a first sheet and a second sheet bonded by the sheet bonding method of the present invention;

[0023] Figure 5 A side view of forming a first groove on an adhesive layer using a release film;

[0024] Figure 6 is a schematic diagram of another embodiment of a cross section of a first groove;

[0025] Figure 7 is a schematic diagram of another embodiment of a cross section of a first groove;

[0026] Figure 8 A schematic diagram of another embodiment of the first groove arrangement;

[0027] Fig. 9 is a schematic diagram of another embodiment of the groove structure on the adhesive layer;

[0028] Fig.10 A schematic diagram of another embodiment of forming a first groove;

[0029] Fig.11 for Fig.10 A schematic diagram of a first sheet material and a second sheet material being bonded together;

[0030] Fig.12 is a side view of the touch panel of the second embodiment;

[0031] Fig.13 for Fig.12 A schematic diagram of the bonding of various plate-like structures in the middle touch panel;

[0032] Fig.14 for Fig.12 Schematic diagram of bonding the light guide plate and the reflective sheet of the middle plate-shaped light guide structure. DETAILED DESCRIPTION

[0033] In order to provide a further understanding of the purpose, structure, features and functions of the present invention, the following detailed description is given in conjunction with the embodiments.

[0034] See also Figures 1 to 4 , Figure 1 is a flow chart of a sheet bonding method according to a first embodiment of the present invention, Figure 2 A side view of a first sheet and a second sheet prepared for the sheet bonding method of the present invention, Figure 3 for Figure 2A top view of the adhesive layer on the first sheet, Figure 4 FIG. 1 is a side view of a first sheet and a second sheet bonded by the sheet bonding method of the present invention. In a first embodiment, the sheet bonding method of the present invention is used in the manufacture of a touch panel, and the sheet bonding method includes preparing a first sheet 1 and a second sheet 2, such as Figure 1 As shown in step S100. The first sheet 1 has a first surface 12, and the adhesive layer 3 is formed on the first surface 12. The second sheet 2 has a second surface 22. A plurality of first grooves 40 are formed on the adhesive layer 3. The plurality of first grooves 40 extend parallel to a first direction D1, and the first grooves 40 have an open end 402 in the first direction D1, and have an open end 404 in a direction opposite to the first direction D1 (such as Figure 3 Then, the sheet bonding method bonds the first sheet 1 (the first surface 12) and the second sheet 2 (the second surface 22) together via the adhesive layer 3, as shown in FIG. Figure 1 As shown in step S102. The adhesive layer 3 has plasticity. In actual operation, the adhesive layer 3 can be selected according to actual bonding requirements, such as but not limited to optical adhesive (OCA), water-based adhesive (OCR), etc.

[0035] like Figure 4 As shown in FIG. 1 , after the first sheet 1 and the second sheet 2 are bonded together, the plurality of first grooves 40 disappear, so that the first sheet 1 and the second sheet 2 can be firmly bonded together. Figure 4 From a perspective of FIG. 1 , the first sheet 1 and the second sheet 2 are overlapped in a vertical direction Dv (which is perpendicular to the first direction D1), and the first surface 12 is opposite to the second surface 22. In the process of bonding the first sheet 1 and the second sheet 2 together via the adhesive layer 3, air can be discharged from between the first sheet 1 (the first surface 12) and the second sheet 2 (the second surface 22) through the plurality of first grooves 40 (and from the open ends 402 and 404), thereby suppressing or preventing the formation of bubbles between the first surface 12 and the second surface 22.

[0036] In addition, if Figure 5 As shown, in step S100, in actual operation, the adhesive layer 3 can be formed on the first surface 12 of the first sheet 1 by coating (e.g., brushing) or other methods (e.g., OCA double-sided tape), and a release film 6 is attached to the adhesive layer 3 to form a plurality of first grooves 40 on the adhesive layer 3. The release film 6 has a plurality of protruding structures 62. When the release film 6 is attached to the adhesive layer 3, the release film 6 forms a plurality of first grooves 40 on the adhesive layer 3 through the plurality of protruding structures 62. In addition, before step S102, the release film 6 needs to be removed from the adhesive layer 3 to expose the plurality of first grooves 40.

[0037] In addition, if Figure 2As shown, in the first embodiment, the cross-section of the first groove 40 is a rectangle, and its width 40a, depth 40b and spacing 40c can all be determined according to actual bonding tests. Moreover, in actual operation, the distance from the bottom of the first groove 40 to the first surface 12 of the first sheet 1 (i.e., the minimum thickness 40d of the adhesive layer 3) can also be determined according to actual tests. For example, the minimum thickness 40d can be designed to match the size of the cross-section of the first groove 40 (including the width 40a, depth 40b and spacing 40c). For example, the minimum thickness 40d is designed to be 0 (i.e., the first surface 12 is directly used as the bottom of the first groove 40). In addition, in actual operation, the cross-section of the first groove 40 can also be other shapes, such as Figure 6 The cross section of the first groove 41a shown is arc-shaped. Figure 7 As shown, the cross section of the first groove 41b is V-shaped. The aforementioned various cross-sectional shapes can be realized by designing the size of the protruding structure 62 on the release film 6, which will not be described in detail. In addition, in actual operation, the first groove 40 is not limited to extending in a single cross section.

[0038] In addition, if Figure 3 As shown in FIG. 1 , in the first embodiment, the first groove 40 completely penetrates the surface of the adhesive layer 3 along the first direction D1, but the actual operation is not limited thereto. Figure 8 As shown, one group of first grooves 41c has only one open end 412c in the first direction D1, and another group of first grooves 41d has only one open end 412d in the direction opposite to the first direction D1. The vertical projections of the first grooves 41c and the first grooves 41d in the horizontal direction Dh (indicated by a double-headed arrow in the figure, which is perpendicular to both the vertical direction Dv and the first direction D1) partially overlap, that is, the plurality of grooves extend along one direction (the horizontal direction Dh in this embodiment) and are arranged, and the vertical projections of one group of first grooves 40c and the other group of first grooves 40d in the arrangement direction of the plurality of first grooves 40 partially overlap, but this is not limited to the actual operation.

[0039] In addition, in the first embodiment, the adhesive layer 3 covers the entire first surface 12 of the first sheet 1, but this is not limited to the actual operation. In addition, the first direction D1 is parallel to the edge of the adhesive layer 3 (also parallel to the edge of the first surface 12), but this is not limited to the actual operation. The selection of the first direction D1 can be determined according to the actual bonding method. For example, in the case where the first sheet 1 and the second sheet 2 are bonded by rolling, the first direction D1 can be set to be not perpendicular to the rolling direction, so that during the rolling process, the air between the first sheet 1 and the second sheet 2 can be easily discharged through the first groove 40.

[0040] As described above, in the first embodiment, the adhesive layer 3 has only a groove structure extending in a single direction (ie, a plurality of first grooves 40), but the actual operation is not limited thereto. Fig. 9 As shown, the groove structure on the adhesive layer 3 includes a plurality of first grooves 40' and a plurality of second grooves 42. The plurality of first grooves 40' extend in parallel in a first direction D1' (indicated by arrows in the figure), and the plurality of second grooves 42 extend in parallel in a second direction D2 (indicated by arrows in the figure). The first direction D1' and the second direction D2 are not parallel, or there is an angle A1 between the two, and the angle A1 is not 0 or 180 degrees. The first groove 40' has an open end 402' and an open end 404' in the first direction D1' and in a direction opposite to the first direction D1', respectively. The second groove 42 has an open end 422 in the first direction D1' and in a direction opposite to the second direction D2. The structural design of the first groove 40' and the second groove 42 is the same as that of the first groove 40 in the first embodiment, so the previous description of the first groove 40 and its variations is also applicable here and will not be repeated. In addition, in Fig. 9 The selection of the angle A1 can be determined according to actual bonding tests, such as but not limited to 30 degrees, 45 degrees, 60 degrees, 75 degrees, 90 degrees, 105 degrees, 120 degrees, 135 degrees, 150 degrees, etc.

[0041] In addition, in the first embodiment, a plurality of first grooves 40 are formed on the adhesive layer 3, but the actual operation is not limited thereto. Fig.10 As shown, a plurality of first grooves 40" are formed on the second surface 22 of the second sheet 2, and the adhesive layer 3 (eg, optical adhesive or water-based adhesive) remains flat on the surface facing the second surface 22. Fig.11 As shown, after the first sheet 1 and the second sheet 2 are bonded together via the adhesive layer 3, the structure of the multiple first grooves 40" is still maintained, and the adhesive layer 3 and the multiple first grooves 40" are tightly fitted. Similarly, in the process of bonding the first sheet 1 and the second sheet 2 together via the adhesive layer 3, air can be discharged between the first sheet 1 (the first surface 12) and the second sheet 2 (the second surface 22) through the multiple first grooves 40", thereby suppressing or preventing the formation of bubbles between the first surface 12 and the second surface 22. In addition, in actual operation, the multiple first grooves 40" can be formed integrally with the second sheet 2, or formed by providing other structures on the second surface 22, such as printing other materials (such as ink) on the second surface 22, but the actual operation is not limited to this. In addition, the previous descriptions of the first groove 40, the first groove 40', the second groove 42 and their variations are also applicable here (for example, multiple second grooves are also formed on the second surface 22 of the second sheet 2) and will not be repeated.

[0042] See also Fig.12The touch panel 5 of the second embodiment of the present invention includes a plate-shaped touch sensing component 52, a plate-shaped light guide structure 54, a cover plate 56 and other required electronic components (not shown in the figure, such as a controller, a light source, etc.). The plate-shaped touch sensing component 52 (for example, but not limited to, including an optical or capacitive plate-shaped sensor), the plate-shaped light guide structure 54 (for example, but not limited to, including a light guide plate, and may further include a reflective sheet) and the cover plate 56 (for example, but not limited to, a light-transmissive glass plate) are stacked together in sequence in the vertical direction Dv. The plate-shaped touch sensing component 52 and the plate-shaped light guide structure 54, and the plate-shaped light guide structure 54 and the cover plate 56 are bonded with an adhesive layer 58 and an adhesive layer 60, respectively, and the bonding method may adopt the sheet bonding method described above. For example, as Fig.13 As shown, during the bonding process of the plate-like touch sensing component 52 and the plate-like light guide structure 54, the plate-like light guide structure 54 is regarded as the first sheet material, and the plate-like touch sensing component 52 is regarded as the second sheet material, and an adhesive layer 58 is formed on the surface of the plate-like light guide structure 54 facing the plate-like touch sensing component 52, and a groove structure is formed on the surface of the adhesive layer 58 facing the plate-like touch sensing component 52; during the bonding process of the cover plate 56 and the plate-like light guide structure 54, the plate-like light guide structure 54 is regarded as the first sheet material, and the cover plate 56 is regarded as the second sheet material, and an adhesive layer 60 is formed on the surface of the plate-like light guide structure 54 facing the cover plate 56, and a groove structure is formed on the surface of the adhesive layer 60 facing the cover plate 56. In addition, Fig.13 In the embodiment, the adhesive layer 58 can also be formed on the surface of the plate-like touch sensing component 52 facing the plate-like light guide structure 54 (in this case, it is equivalent to regarding the plate-like touch sensing component 52 as the first sheet and the plate-like light guide structure 54 as the second sheet), and the groove structure is still formed on the adhesive layer 58 (the surface facing the plate-like light guide structure 54); similarly, the adhesive layer 60 can also be formed on the surface of the cover plate 56 facing the plate-like light guide structure 54 (in this case, it is equivalent to regarding the cover plate 56 as the first sheet and the plate-like light guide structure 54 as the second sheet), and the groove structure is still formed on the adhesive layer 58 (the surface facing the plate-like light guide structure 54). In addition, the above descriptions of the adhesive layer 3, the first groove 40, the first groove 40', the second groove 42 and their variations (such as the setting position and extension conditions, the extension conditions include the cross section, direction, length, etc.) are also applicable here and will not be repeated.

[0043] In addition, in actual operation, the stacking order of the plate-shaped touch sensing component 52, the plate-shaped light guide structure 54 and the cover plate 56 is not necessarily the same as that of the plate-shaped touch sensing component 52. Fig.12The stacking sequence can also be that the plate-shaped touch sensing component 52 is stacked on the plate-shaped light guide structure 54, and the cover plate 56 is stacked on the plate-shaped touch sensing component 52. The three-layer plate-shaped structural components can still use the sheet bonding method described above, which will not be repeated. In other words, when the sheet bonding method is applied, two of the group consisting of the plate-shaped touch sensing component 52, the plate-shaped light guide structure 54 and the cover plate 56 can be regarded as the first sheet and the second sheet respectively.

[0044] In addition, if Fig.14 As shown, in actual operation, the plate-like light guide structure 54 may include a light guide plate 542 and a reflective sheet 544. The light guide plate 542 and the reflective sheet 544 are bonded together via an adhesive layer 546. A printed ink layer 548 (for example, to enhance or weaken the reflection effect) is disposed on the reflective sheet 544 (the surface facing the light guide plate 542), forming a plurality of first grooves 550. Similarly, the bonding of the light guide plate 542 and the reflective sheet 544 may also adopt the sheet bonding method described above. Among them, the light guide plate 542 is regarded as the first sheet, the reflective sheet 544 is regarded as the second sheet, and the adhesive layer 546 is formed on the surface facing the reflective sheet 544. The above descriptions on the first groove 40, the first groove 40', the second groove 42 and their variations are also applicable here and will not be repeated.

[0045] The sheet bonding method provided by the present invention is used in the production of a touch panel. In the process of bonding the first sheet and the second sheet together via the adhesive layer, air is discharged between the first sheet and the second sheet via the plurality of grooves. Thus, when the first sheet and the second sheet are relatively pressed together, the air between the two can flow along the plurality of grooves and be discharged via the open ends of the plurality of grooves, so the sheet bonding method can effectively suppress the generation of bubbles.

[0046] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A sheet bonding method for use in the manufacture of a touch panel, characterized in that: The sheet bonding method comprises the following steps: (a) preparing a first sheet and a second sheet, wherein the first sheet has a first surface, an adhesive layer is formed on the first surface, and the second sheet has a second surface, a plurality of first grooves are formed on the second surface or the adhesive layer, the plurality of first grooves extend in parallel in a first direction, and the first grooves have open ends in the first direction; as well as (b) bonding the first sheet material and the second sheet material together via the adhesive layer; In the process of bonding the first sheet material and the second sheet material together via the adhesive layer, air is discharged between the first sheet material and the second sheet material via the plurality of first grooves.

2. The sheet bonding method according to claim 1, characterized in that: The multiple first grooves are formed on the adhesive layer, and the multiple first grooves completely penetrate the surface of the adhesive layer along the first direction; or, the multiple first grooves are formed on the adhesive layer, one group of first grooves has only one open end along the first direction, and the other group of first grooves has an open end in a direction opposite to the first direction, and the vertical projections of the two groups of first grooves in the arrangement direction of the multiple first grooves partially overlap.

3. The sheet bonding method according to claim 2, characterized in that: The plurality of first grooves are formed on the adhesive layer. Step (a) also includes providing a release film having a plurality of protruding structures, attaching the release film to the adhesive layer and forming the plurality of first grooves on the adhesive layer through the plurality of protruding structures. The sheet bonding method also includes, before step (b), removing the release film from the adhesive layer.

4. The sheet bonding method according to claim 2, characterized in that: The plurality of first grooves are formed on the adhesive layer, and the bottom of the first groove is the first surface.

5. The sheet bonding method according to claim 1, wherein: The first sheet material and the second sheet material are any two of a plate-shaped touch sensing component, a plate-shaped light guide structure and a cover plate.

6. The sheet bonding method according to claim 1, wherein: The first sheet material is a light guide plate, and the second sheet material is a reflective sheet.

7. The sheet bonding method according to claim 6, characterized in that: A printing ink layer is disposed on the reflective sheet, and a plurality of first grooves are formed on the printing ink layer.

8. The sheet bonding method according to claim 1, wherein: The cross section of the first groove is rectangular, arc-shaped or V-shaped.

9. The sheet bonding method according to claim 1, wherein: The first groove has an open end in a direction opposite to the first direction.

10. The sheet bonding method according to claim 1, wherein: In step (a), a plurality of second grooves are formed on the second surface or the adhesive layer. The plurality of second grooves extend in parallel in a second direction. The second grooves have open ends in the second direction. The second direction is not parallel to the first direction.

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