Foldable touch display device

Abstract

The invention provides a foldable touch display device. The foldable touch display device comprises a display module, a touch sensing film, a plurality of transmission lines and a first adhesive layer, the display module comprises an upper surface, a side surface and a lower surface. The touch sensing film is arranged on the lower surface of the display module, extends and bends from the side surface to the upper surface, and comprises a plurality of electrode wires arranged on one side of the touch sensing film. The transmission lines cover one ends of the electrode wires on the upper surface of the display module. The first adhesive layer is disposed on a side of the touch sensing film adjacent to the display module. According to the foldable touch display device, the effects of reducing the curvature radius of the bending area and reducing the overall thickness of the device body can be achieved.

Description

[0001] This application is a divisional application of a patent application with an application date of May 22, 2020, application number 202010442825.4, and invention name “Foldable touch display device”. Technical Field

[0002] The invention relates to a touch display device, and in particular to a touch display device with an extremely narrow frame. Background Art

[0003] In recent years, with the development of touch panel technology, touch panels have been widely used in various electronic devices. At present, narrow frame and full screen are the current trend. The existing technology realizes narrow frame design by folding the circuit area on the side of the touch sensing film to the back of the liquid crystal module.

[0004] In the current design of the reverse bending, the flexible characteristics of the flexible circuit board are used to bend in the bending area. However, since too many flexible circuit boards are in the bending area, the overall thickness will increase. Therefore, how to make the touch display device thinner and lighter and the curvature radius of the bending area smaller is necessary for the existing technology to be improved. Summary of the invention

[0005] An object of an embodiment of the present disclosure is to provide a foldable touch display device, which reduces the curvature radius of a bending area by extending electrode lines.

[0006] One embodiment of the present disclosure provides a foldable touch display device, comprising a display module, a touch sensing film, a plurality of transmission lines, and a first adhesive layer. The display module comprises an upper surface, a side surface, and a lower surface. The touch sensing film is disposed on the lower surface of the display module, and extends and bends through the side surface to the upper surface, and the touch sensing film comprises a plurality of electrode lines disposed on one side of the touch sensing film. The transmission lines cover one end of the electrode lines located on the upper surface of the display module. The first adhesive layer is disposed on one side of the touch sensing film adjacent to the display module.

[0007] In some embodiments, the electrode lines adjacent to the side surface and the upper surface have a line width greater than 0.4 mm.

[0008] In some embodiments, the transmission lines extend along the touch sensing film to the intersection of the adjacent side surface and the bottom surface, and cover the electrode lines.

[0009] In some embodiments, the electrode lines adjacent to the side surface and the upper surface have a line width less than 0.4 mm.

[0010] In some embodiments, the foldable touch display device further includes a protection layer disposed on the outer sides of the transmission lines covering the electrode lines, so that the transmission lines are located between the electrode lines and the protection layer.

[0011] In some embodiments, the display module further includes an electronic paper component and a light guide plate disposed under the electronic paper component, wherein the first adhesive layer is disposed between the light guide plate and the touch sensing film.

[0012] In some embodiments, the foldable touch display device further includes a second adhesive layer disposed between the electronic paper assembly and the light guide plate.

[0013] In some embodiments, the foldable touch display device further includes a third adhesive layer disposed below the lower surface of the touch sensing film relative to the display module, extending along the touch sensing film and bending through the side surface of the display module to the upper surface.

[0014] In some embodiments, the foldable touch display device further includes a cover plate disposed below the lower surface of the touch sensing film opposite to the display module.

[0015] In some embodiments, the material of the electrode wires includes nano-silver paste, nano-silver mixture, nano-silver polymer or a combination thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The various aspects of the present disclosure will be most easily understood when the following detailed description is read in conjunction with the accompanying drawings. It should be noted that various features may not be drawn to scale in accordance with industry standard operating procedures. In fact, the size of various features may be arbitrarily increased or decreased for clarity of discussion.

[0017] Figure 1 A cross-sectional view of a foldable touch display device according to a first embodiment of the present disclosure is shown;

[0018] Figure 2 A schematic diagram showing the electrode lines and transmission lines of the first embodiment of the present disclosure;

[0019] Figure 3 A schematic diagram showing electrode lines and transmission lines according to a second embodiment of the present disclosure is shown;

[0020] Figure 4 A cross-sectional view of a foldable touch display device according to a third embodiment of the present disclosure is shown;

[0021] Figure 5 A schematic diagram showing electrode lines and transmission lines according to a third embodiment of the present disclosure is shown;

[0022] Figure 6 A schematic diagram showing electrode lines and transmission lines according to a fourth embodiment of the present disclosure is shown;

[0023] Figure 7 A cross-sectional view of a foldable touch display device according to a fifth embodiment of the present disclosure is shown;

[0024] Figure 8 A schematic diagram showing electrode lines and transmission lines according to a fifth embodiment of the present disclosure is shown;

[0025] Fig. 9 A cross-sectional view of a foldable touch display device according to a sixth embodiment of the present disclosure is shown.

[0026]

Explanation of symbols

[0027] 100…Foldable touch display device

[0028] 110…Display module

[0029] 1101…Top surface

[0030] 1102…Side surface

[0031] 1103…lower surface

[0032] 111…Electronic paper components

[0033] 112…Light guide plate

[0034] 120…Touch sensor film

[0035] 121…Electrode wire

[0036] 130…Transmission lines

[0037] 140…First adhesive layer

[0038] 150…Second adhesive layer

[0039] 160…Cover

[0040] 161…Light-shielding layer

[0041] 170…Third adhesive layer

[0042] 180…Protective layer

[0043] BA…Bending Zone

[0044] BL…Bending Line

[0045] VA…Visual Area

[0046] D…Line Width

[0047] X…X axis

[0048] Y…Y axis

[0049] R…radius of curvature DETAILED DESCRIPTION

[0050] In order to make the description of the disclosure more detailed and complete, the following is an illustrative description of the implementation and specific embodiments of the present invention, but this is not the only form of implementing or using the specific embodiments of the present invention. The various embodiments disclosed below can be combined or replaced with each other in a beneficial situation, and other embodiments can be added to one embodiment without further recording or explanation. In the following description, many specific details will be described in detail so that the reader can fully understand the following embodiments. However, the embodiments of the present invention can also be practiced without these specific details.

[0051] In addition, spatially relative terms, such as "lower", "upper", etc., are used to conveniently describe the relative relationship of an element or feature to other elements or features in the drawings. These spatially relative terms are intended to encompass different orientations of the device when in use or operation in addition to the orientation shown in the drawings. The device may be otherwise oriented (e.g., rotated 90 degrees or in other orientations), and the spatially relative descriptions used herein should be interpreted accordingly.

[0052] In this document, unless the context specifically limits the article, "a", "an" and "the" may refer to one or more. It will be further understood that "comprising", "including", "having" and similar words used in this document specify the features, regions, integers, steps, operations, elements and / or components recorded therein, but do not exclude other features, regions, integers, steps, operations, elements, components, and / or groups thereof.

[0053] Several embodiments and experimental examples are listed below to further illustrate the foldable touch display device of the present invention. However, they are only for illustration and are not intended to limit the present invention. The protection scope of the present invention shall be based on the scope defined in the appended claims.

[0054] Example 1

[0055] Figure 1 is a cross-sectional view of a foldable touch display device according to a first embodiment of the present disclosure. Figure 2 The foldable touch display device 100 includes a display module 110 , a touch sensing film 120 , a plurality of transmission lines 130 , a first adhesive layer 140 , a second adhesive layer 150 , a cover plate 160 and a third adhesive layer 170 .

[0056] The display module 110 has an upper surface 1101, a side surface 1102, and a lower surface 1103. Regarding the state of the display module 110, a person with ordinary knowledge in the field can select a suitable display module and is not limited thereto. In one embodiment, the display module 110 includes an electronic paper component 111 and a light guide plate 112, and the light guide plate 112 is disposed under the electronic paper component 111 (such as an electronic paper display). In another embodiment, the display module 110 can be replaced with a backlight module, such as an organic light-emitting diode (OLED).

[0057] The touch sensing film 120 is disposed on the lower surface 1103 of the display module 110, and extends and bends through the side surface 1102 to the upper surface 1101. Specifically, the touch sensing film 120 is disposed on the lower surface 1103 of the display module 110, and extends to the side surface 1102 and a portion of the upper surface 1101 adjacent to the side surface 1102, so as to show that the touch sensing film 120 is bent at the side surface 1102 and slightly extends to the upper surface 1101. The touch sensing film 120 includes a plurality of electrode lines 121 disposed on one side of the touch sensing film 120. In one embodiment, the electrode lines 121 are disposed on a side of the touch sensing film 120 opposite to the display module 110, that is, on the outer side of the touch sensing film 120. In some embodiments, the electrode lines 121 can be formed of a transparent conductive material, and the electrode lines 121 can be obtained by a photoetching process. In this case, the transparent conductive material includes, but is not limited to, nanosilver paste, nanosilver mixture, nanosilver polymer or a combination thereof. In one embodiment, the material of the electrode line 121 is nanosilver. Since nanosilver is flexible, in this embodiment, the nanosilver extends from the visible area VA (visible area) and bends from the bending line BL (bending line) to the upper surface 1101 at the bending area BA (bending area), so that the curvature radius R of the bending area BA is less than 1 mm and the overall thickness is reduced.

[0058] In some embodiments, the touch sensing film 120 includes a first electrode line in the X-axis direction and a second electrode line in the Y-axis direction. The first electrode line and the second electrode line are disposed on two opposite sides of the touch sensing film 120. The first electrode line extends from the visual area VA toward the X-axis direction and is bent at the bending area BA to the upper surface 1101. The second electrode line extends from the visual area VA toward the Y-axis direction and is bent at the bending area BA to the upper surface 1101. The electrode lines of this embodiment are not limited to extending and bending toward the left side on the X-axis and the upper side on the Y-axis, and may further include extending and bending toward the right side on the X-axis and / or the lower side on the Y-axis as required.

[0059] The plurality of transmission lines 130 cover one end of the electrode lines 121 located on the upper surface 1101 of the display module 110. Regarding the state of the electrode lines 121, a person skilled in the art can select a suitable number of electrode lines as a group to be electrically connected to one of the plurality of transmission lines 130. In some embodiments, the electrode lines 121 are electrically connected to one of the plurality of transmission lines 130 in a group of two (e.g., Figure 2 shown); Figure 2 The plurality of electrode lines are only schematically shown, and the specific number depends on the product size and design. The materials of the plurality of transmission lines 130 include, but are not limited to, indium tin oxide, silver, zinc, copper, gold, platinum, tungsten, aluminum, or alloys of the above metals. In some embodiments, the plurality of transmission lines 130 are part of a flexible printed circuit board.

[0060] The first adhesive layer 140 is disposed on a side of the touch sensing film 120 adjacent to the display module 110. Specifically, the touch sensing film 120 and the first adhesive layer 140 are disposed on the lower surface 1103 of the display module 110, and are extended to the side surface 1102 and a portion of the upper surface 1101 adjacent to the side surface 1102, so that the touch sensing film 120 and the first adhesive layer 140 are bent at the side surface 1102 and slightly extended to the upper surface 1101. In some embodiments, the first adhesive layer 140 is an optical colloid (OCA), biaxially-oriented polyethylene terephthalate (BoPET, also known as ) or PET with OCA, the penetration rate is greater than 60%, or even greater than 80%.

[0061] The second adhesive layer 150 is disposed between the electronic paper assembly 111 and the light guide plate 112. In some embodiments, the second adhesive layer 150 is optical colloid (OCA), BoPET or PET with OCA, and its transmittance is greater than 60%, or even greater than 80%.

[0062] The cover plate 160 is disposed below the lower surface 1103 of the touch sensing film 120 relative to the display module 110. In one embodiment, the cover plate 160 can be a transparent inorganic substrate, such as a glass substrate; or a transparent organic substrate, such as a plastic substrate, and its material is, for example, polyethylene terephthalate (PET), polycarbonate (PC), polyethylene (PE) or polymethylmethacrylate (PE). In one embodiment, a light shielding layer 161 is disposed above the side surface 1102 of the display module 110 relative to the cover plate 160. The light shielding layer 161 can be formed by opaque ink, such as black ink, white ink, etc. For example, the transmittance of the light shielding layer 161 is less than 20%.

[0063] The third adhesive layer 170 is disposed between the cover plate 160 and the touch sensing film 120. In some embodiments, the third adhesive layer 170 is PET with optical colloid (OCA), and its transmittance is greater than 60%, or even greater than 80%.

[0064] Example 2

[0065] Figure 3 A schematic diagram of the electrode lines and transmission lines of the second embodiment of the present disclosure is shown. Figure 1 and Figure 3The difference between the second embodiment and the first embodiment is that the line width D of the electrode lines 121 adjacent to the side surface 1102 and the upper surface 1101 of the display module 110 is greater than 0.4 mm, for example, the line width D is between 0.4-100 mm. In some embodiments, the line width D is, for example, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.6 mm, 5.0 mm, 10 mm, 50 mm, 100 mm, or any value between any two of these values. In one embodiment, the electrode lines 121 are grouped as four adjacent electrode lines 121. When the four electrode lines 121 are located at the intersection of the side surface 1102 and the lower surface 1103 of the adjacent display module 110, the innermost two electrode lines 121 are connected, so that the outermost two electrode lines 121 are located at the adjacent side surface 1102 and the upper surface 1101, and the line width D is greater than 0.4 microns, for example, the line width D is between 0.4-100 mm. In some embodiments, the line width D is, for example, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.6 mm, 5.0 mm, 10 mm, 50 mm, 100 mm, or any value between any two of these values. Therefore, in this embodiment, by widening the line width D of the electrode line 121 in the bending area BA so that the curvature radius R of the bending area BA is less than 1 mm and the impedance of the bending area BA is less than 100 ohms per square (ohm / square), the signal transmission is faster.

[0066] Example 3

[0067] Figure 4 A cross-sectional view of a foldable touch display device according to a third embodiment of the present disclosure is shown. Figure 5 A schematic diagram of electrode lines and transmission lines of the third embodiment of the present disclosure is shown. The difference between the third embodiment and the first embodiment is that the transmission lines 130 extend along the touch sensing film 120 to the intersection of the side surface 1102 and the lower surface 1103 of the adjacent display module 110, and cover the electrode lines 121. Specifically, the transmission lines 130 extend from one end of the electrode lines 121 covering the upper surface 1101 of the display module 110, along the touch sensing film 120 to the intersection of the side surface 1102 and the lower surface 1103 of the adjacent display module 110, and cover the electrode lines 121. In one embodiment, the transmission lines 130 and the electrode lines 121 are bonded by optical adhesive (OCA). By extending the transmission line 130 to the bending area BA, the impedance in the bending area BA is reduced to less than 10 ohms / square without increasing the line width between the electrode lines 121 (eg, maintaining the line width at 0.2 mm), thereby achieving a smaller curvature radius (eg, R<0.5 mm).

[0068] Example 4

[0069] Figure 6 A schematic diagram of the electrode lines and transmission lines of the fourth embodiment of the present disclosure is shown. Figure 4 and Figure 6 , the difference between the fourth embodiment and the second embodiment is that the transmission lines 130 extend along the touch sensing film 120 to the intersection of the side surface 1102 and the lower surface 1103 of the adjacent display module 110, and cover the electrode lines 121. Specifically, the transmission lines 130 extend from one end of the upper surface 1101 of the display module 110 covering the electrode lines 121, along the touch sensing film 120 to the intersection of the side surface 1102 and the lower surface 1103 of the adjacent display module 110, and cover the electrode lines 121. By extending the transmission lines 130 to the bending area BA, while increasing the line width D between the electrode lines 121 (as described in the second embodiment, which will not be repeated here), the impedance of the electrode lines 121 located in the bending area BA is made less than 10 ohms / square, so as to achieve a smaller radius of curvature (for example, R<0.5mm).

[0070] Example 5

[0071] Figure 7 A cross-sectional view of a foldable touch display device according to a fifth embodiment of the present disclosure is shown. Figure 8 A schematic diagram of the electrode lines and transmission lines of the fifth embodiment of the present disclosure is shown. The difference between the fifth embodiment and the third and fourth embodiments is that the foldable touch display device 100 further includes a protective layer 180, which is disposed on the outside of the transmission lines 130 covering the electrode lines 121, so that the transmission lines 130 are between the electrode lines 121 and the protective layer 180. In one embodiment, in addition to covering the transmission lines 130, the protective layer 180 directly covers the touch sensing film 120 in places where there are no transmission lines 130. In some embodiments, the thickness of the protective layer 180 is less than 30 microns, for example, between 1 micron and 30 microns. In one embodiment, the thickness of the protective layer 180 is 2 microns, 4 microns, 6 microns, 8 microns, 10 microns, 15 microns, 20 microns, 25 microns, or any value between any two of these values. In one embodiment, the material of the protective layer 180 includes, but is not limited to, epoxy, acrylic acid copolymer (or acrylic acid, poly(methylmethacrylate), PMMA), ethyl diethylene glycol acetate, or a combination thereof. Specifically, the protective layer 180 is a protective ink.

[0072] Example 6

[0073] Fig. 9 A cross-sectional view of a foldable touch display device of the sixth embodiment of the present disclosure is shown. The difference between the sixth embodiment and the fifth embodiment is that the foldable touch display device 100 further includes a third adhesive layer 170 disposed between the cover plate 160 and the touch sensing film 120, and extending along the touch sensing film 120 and bending through the side surface 1102 of the display module 110 to the upper surface 1101. In some embodiments, the third adhesive layer 170 is an optical colloid (OCA) with a transmittance greater than 60%, or even greater than 80%. In some embodiments, the thickness of the third adhesive layer 170 is less than 100 microns, for example, between 10 microns and 100 microns. In one embodiment, the thickness of the third adhesive layer 170 is 20 microns, 40 microns, 60 microns, 80 microns, or any value between any two of these values.

[0074] In multiple embodiments disclosed herein, first, the electrode lines are extended to serve as signal lines and bent in the bending zone, thereby improving the traditional situation of too many flexible circuit board lines in the bending zone, so that the overall frame is reduced. Second, by designing different electrode line widths in the bending zone, the impedance in the bending zone is reduced to increase the speed of signal transmission. Third, by extending the transmission line to the bending zone to cover the electrode line, the line width of the electrode line in the bending zone can retain the original line width without the need for additional widening, and can even be shortened. All of the above technical solutions can achieve a smaller radius of curvature in the bending zone to achieve a narrower edge width of the screen, while avoiding electrical interference from the front transmission line.

[0075] Although the present disclosure has been disclosed in the above embodiments, it is not intended to limit the present disclosure. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be based on the scope defined by the attached claims.

Claims

1. A foldable touch display device, characterized in that: Include: A display module comprising an upper surface, a side surface and a lower surface; A touch sensing film is disposed on the lower surface of the display module and extends and bends through the side surface to the upper surface. The touch sensing film includes: A plurality of electrode lines are disposed on one side of the touch sensing film, wherein the plurality of electrode lines extend from a visible area and bend from a bending line at a bending area to the upper surface; a flexible printed circuit board, comprising a plurality of transmission lines, covering one end of the plurality of electrode lines located on the upper surface of the display module and covering the plurality of electrode lines; and a first adhesive layer disposed on a side of the touch sensing film adjacent to the display module, Wherein, the impedance of the plurality of electrode lines located in the bending area is less than 10 ohms / square, and the curvature radius R is less than 0.5 mm.

2. The foldable touch display device according to claim 1, characterized in that: The electrode lines adjacent to the side surface and the upper surface have line widths greater than 0.4 mm.

3. The foldable touch display device according to claim 1, characterized in that: The plurality of transmission lines extend along the touch sensing film to the junction of the adjacent side surface and the lower surface.

4. The foldable touch display device according to claim 3, characterized in that: The electrode lines adjacent to the side surface and the upper surface have line widths less than 0.4 mm.

5. The foldable touch display device according to claim 3, characterized in that: The invention also comprises a protection layer, which is arranged on the outer sides of the transmission lines covering the electrode lines, so that the transmission lines are located between the electrode lines and the protection layer.

6. The foldable touch display device according to claim 1, characterized in that: The display module further comprises an electronic paper component and a light guide plate arranged under the electronic paper component, wherein the first adhesive layer is located between the light guide plate and the touch sensing film.

7. The foldable touch display device according to claim 6, characterized in that: It also includes a second adhesive layer, which is arranged between the electronic paper component and the light guide plate.

8. The foldable touch display device according to claim 1, wherein: The invention also comprises a third adhesive layer which is arranged below the lower surface of the touch sensing film relative to the display module, and extends along the touch sensing film and is bent through the side surface of the display module to the upper surface.

9. The foldable touch display device according to claim 1, characterized in that: The invention also comprises a cover plate, which is arranged below the lower surface of the touch sensing film relative to the display module.

10. The foldable touch display device according to claim 1, wherein: The material of the plurality of electrode lines includes nano silver paste, nano silver mixture, nano silver polymer or a combination thereof.

Images