Foldable ultra-thin glass cover with circular polarization and touch screen functions and manufacturing method

Abstract

The present invention discloses a foldable ultra-thin glass cover with circular polarization and touch screen functions, comprising ultra-thin glass, an ink frame printed below the ultra-thin glass, an explosion-proof layer coated below the ink frame, a nano-scale WGP polarizer printed below the explosion-proof layer, a 1 / 4λ phase difference film coated below the nano-scale WGP polarizer, and a touch circuit layer printed below the 1 / 4λ phase difference film. The functional layer is coated by printing and coating, which not only integrates the functions of touch screen and circular polarization, but also saves the thickness and bonding process of optical glue, PET film, and traditional circular polarizer substrate, so that the functions of circular polarization and touch screen are integrated with the glass cover, making the glass cover with circular polarization and touch screen functions easier to fold without creases.

Description

Technical Field

[0001] The present invention belongs to the field of foldable display screens for mobile phones, and more specifically relates to a foldable ultra-thin glass cover plate with circular polarization and touch screen functions and a manufacturing method thereof. Background Art

[0002] Since the beginning of 2019, companies including Samsung and BOE have successively released self-developed foldable self-luminous OLED flexible screens. According to online news, Samsung, Huawei, Royole, Xiaomi and other companies have also made related foldable mobile phone products. China Unicom even said in its official Weibo that "foldable screen mobile phones are not far away!"

[0003] The flexible screen, which is indispensable in foldable screen mobile phones, not only has super portability, but also has the advantages of high resolution, high brightness, and low energy consumption. In the future, mobile phones using this technology will not only provide high picture quality, but also expand battery space to further enhance battery life.

[0004] There are many problems with the foldable screen phones currently released on the market. For example, Samsung's Galaxy Fold was reported to have various problems on the screen as soon as the test machine was released. Therefore, no mobile phone manufacturer has really mass-produced and released foldable screen phones. One of the problems is that the protective cover is made of transparent plastic material, which is not hard enough and is prone to creases.

[0005] In addition to the foldable flexible OLED display panel, the protective cover on the outer layer of the flexible OLED display panel must also be foldable. The glass cover is covered on the OLED panel. In the entire mobile phone display, there are also some other functional layers between the glass cover and the panel layer, such as polarizers and touch screens.

[0006] Chinese patent 201920901725.6 involves a foldable glass cover plate, but does not involve the function of the touch screen. The current traditional touch screen is to first make the touch line on the PET film, and then use optical glue to bond it to the glass cover plate or OLED panel; the polarizer used for OLED must be a circular polarizer, which is a polarizer and a ¼λ phase difference film to achieve circular polarization. The current traditional practice is to bond the circular polarizer separately. If you encounter a folding OLED panel, this method of bonding the touch screen and the circular polarizer directly makes the thickness of the entire folding display thicker, and the touch screen and the circular polarizer are easy to offset with the OLED panel when folding, which is not conducive to screen folding. Especially for the inward folding screen of the Samsung Galaxy Fold mobile phone (the outward folding screen mobile phone like Huawei Mate X, the screen is outside, and the folding angle of the outward folding screen is relatively large compared to the inward folding mobile phone), the requirements for screen folding are particularly high. If the traditional touch screen method is used, the thickness is thicker and not easy to fold, and the touch screen is easy to offset with the glass cover plate or OLED panel.

[0007] For folding screens, the thicker the thickness and the more adhesive layers, the more difficult it is to fold and the larger the foldable angle. Summary of the invention

[0008] In view of the shortcomings of the prior art, the present invention provides a device with a smaller thickness and a functional layer coated by printing and coating, which not only integrates the functions of a touch screen and a circular polarizer, but also eliminates the thickness and bonding process of optical glue, PET film, and a traditional circular polarizer substrate, so that the functions of the circular polarizer and the touch screen are integrated with the glass cover plate, making the glass cover plate with the circular polarizer and touch screen functions easier to fold and without creases.

[0009] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a foldable ultra-thin glass cover with circular polarization and touch screen functions, comprising ultra-thin glass, an ink frame printed under the ultra-thin glass, an explosion-proof layer coated under the ink frame, a nano-scale WGP polarizer printed under the explosion-proof layer, a ¼λ phase difference film coated under the nano-scale WGP polarizer, and a touch circuit layer printed under the ¼λ phase difference film.

[0010] Furthermore, the material of the nano-scale WGP polarizer is nano-silver.

[0011] Furthermore, the explosion-proof layer is a transparent resin coating.

[0012] Furthermore, the transparent resin coating is provided with a plurality of strip-shaped grooves, and the nano-scale WGP polarizer is printed in the grooves.

[0013] Furthermore, the touch circuit layer is a nanosilver touch circuit layer.

[0014] Furthermore, the touch circuit layer is an ITO touch circuit layer.

[0015] Furthermore, the thickness of the ultra-thin glass is 30-100 microns, the thickness of the ink frame is 6-8 microns, and the thickness of the explosion-proof layer is 30-60 microns.

[0016] Furthermore, an anti-fouling coating is provided on the ultra-thin glass.

[0017] A method for manufacturing a foldable ultra-thin glass cover with circular polarization and touch screen functions comprises the following steps:

[0018] 1) On the lower surface of the ultra-thin glass, the required ink frame is printed by gravure printing. The thickness of the ink frame is 6-8 microns;

[0019] 2) A layer of transparent resin coating is applied on the lower surface of the ink frame with a thickness of 30-60 microns;

[0020] 3) Then, a layer of nano-scale WGP polarizer is printed on the lower surface of the transparent resin coating. The specific process is as follows: first, a mold with a convex structure in the shape of stripes is used to form grooves on the transparent resin coating using nanoimprint technology; second, a blade is used to fill only the groove part with metal ink; finally, an oven is used to burn the metal grid WGP polarizer;

[0021] 4) Coating a ¼λ phase difference film under the nanoscale WGP polarizer;

[0022] 5) Print the nanosilver circuit under the ¼λ phase difference film, and then perform laser dry etching to trim the nanosilver circuit; or use ITO, first plate ITO on the lower surface of the ¼λ phase difference film, and then etch the ITO to form a touch circuit layer.

[0023] The method further includes the following step: coating an anti-fouling layer on the upper surface of the ultra-thin glass, and this step is placed before step 1) or after step 5).

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The glass cover provided by the present invention adopts the printing method of nano-scale WGP polarizer to print the polarizer on the body of the glass cover to realize linear polarization, and then uses the coating method to coat a layer of ¼λ phase difference film to realize the circular polarization function. The body of the glass cover is the part where the circular polarization is removed, and the touch layer is printed on the glass cover by nano-silver printing, and no optical adhesive bonding is required. It not only integrates the functions of touch screen and circular polarization, but also saves the thickness and bonding process of optical adhesive, PET film, and traditional circular polarizer substrate, so that the functions of circular polarization and touch screen are integrated with the glass cover, making the glass cover with circular polarization and touch screen functions easier to fold; effectively reducing the bendable angle of the glass cover, and after bending, the touch layer and the glass cover will not be offset, and there will be no creases, which is particularly suitable for mobile phones or electronic devices with inward folding screens;

[0026] 2. 30-60 micron transparent resin coating, low material cost, low process cost, and can effectively achieve explosion-proof effect;

[0027] 3. The ink frame printed by the gravure printing device can be printed in various frame colors such as blue and gold, and can be applied to mobile phones of different colors;

[0028] 4. This application has no optical adhesive layer, no PET layer, and no traditional circular polarizer substrate, so the folding angle is small. For the inward folding screen, the smaller the folding angle, the better. After repeated folding, the protective cover has no folding marks and does not affect the display effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic structural diagram of a foldable ultra-thin glass protective cover with circular polarization and touch screen functions according to the present invention;

[0030] Figure 2 Schematic diagram of the manufacturing process of the nano-scale WGP polarizer in the present invention;

[0031] Figure 3 It is a schematic diagram of the structure of the gravure pad printing device used in the present invention.

[0032] Figure numerals: 1. Anti-fouling coating; 2. Ultra-thin glass; 3. Ink frame; 4.1. Explosion-proof layer; 4.2. Nano-scale WGP polarizer; 5. ¼λ phase difference film; 6. Mold; 7. Groove; 8. Metal ink; 9. Blade; 10. Touch circuit layer; 51. Jig; 52. Pad printing roller; 53. Gravure roller; 54. Ink tank; 55. Ink roller; 56. Scraper. DETAILED DESCRIPTION

[0033] Reference Figures 1 to 3 The embodiment of the foldable ultra-thin glass protective cover with circular polarization and touch screen functions of the present invention is further described.

[0034] In the description of the present invention, it should be noted that directional words, such as the terms "center", "lateral (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of narrating the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and cannot be understood as limiting the specific scope of protection of the present invention.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. Therefore, the definition of "first" and "second" features can explicitly or implicitly include one or more of the features. In the description of the present invention, "several" and "a number" mean two or more, unless otherwise clearly and specifically defined.

[0036] A foldable ultra-thin glass cover with circular polarization and touch screen functions, comprising an ultra-thin glass 2, an ink frame 3 is printed below the ultra-thin glass 2, an explosion-proof layer 4.1 is coated below the ink frame 3, a nano-scale WGP polarizer 4.2 is printed below the explosion-proof layer 4.1, a ¼λ phase difference film 5 is coated below the nano-scale WGP polarizer 4.2, and a touch circuit layer 10 is printed below the ¼λ phase difference film 5.

[0037] The nano-scale WGP polarizer 4.2 and the ¼λ phase difference film together form a circular polarizer, wherein the WGP polarizer is combined with the glass cover body (a combination of the ultra-thin glass 2, the ink frame 3 and the explosion-proof layer 4.1) by printing, eliminating the optical glue and the circular polarizer substrate, so that the function of the circular polarizer is integrated with the glass cover. At the same time, the touch circuit layer is printed under the ¼λ phase difference film, and the optical glue is also eliminated, which effectively reduces the bending angle of the glass cover. Moreover, the circular polarizer and the glass cover body will not be offset after bending.

[0038] In this embodiment, the material of the nano-scale WGP polarizer 4.2 is preferably nano-silver.

[0039] The explosion-proof layer 4.1 of the present embodiment is preferably a transparent resin coating, and the thickness of the transparent resin coating is 30-60 microns. The transparent resin coating with the best application effect at present is CPI, which has a good explosion-proof effect when it reaches a certain thickness, so that when the glass cover is shattered by impact, the glass fragments will not splash out. The transparent resin coating is coated on the ink frame 3.

[0040] The thickness of the ink border 3 is 6-8 microns. It is used to shield components outside the display area of ​​the display screen. It also has a shading effect. The ink border 3 can be printed with various border colors such as blue and gold. The depth of the ink can be achieved through the border template design to achieve a texture effect. Different shapes and colors can be printed multiple times to achieve color and pattern effects. Ink borders 3 of different colors can be suitable for mobile phones of different colors.

[0041] The ink frame 3 is printed on the edge of the ultra-thin glass 2 . When the explosion-proof layer 4 . 1 is actually coated, a portion of the explosion-proof layer 4 . 1 contacts the ink frame 3 , and another portion contacts the surface of the ultra-thin glass 2 .

[0042] In this embodiment, the transparent resin coating is preferably provided with a plurality of strip-shaped grooves 7, and the nano-scale WGP polarizer 4.2 is printed in the grooves.

[0043] In this embodiment, the touch circuit layer is preferably a nano-silver touch circuit layer.

[0044] Or the touch circuit layer is an ITO touch circuit layer.

[0045] In the present embodiment, the thickness of the ultra-thin glass 2 is preferably 30-100 microns, the thickness of the ink frame 3 is 6-8 microns, and the thickness of the explosion-proof layer 4.1 is 30-60 microns.

[0046] The ultra-thin glass 2 used in this solution is an ultra-thin tempered glass with a thickness of 30-100 microns. In 2013, German Schott began to supply 25-100μm thick flexible glass in batches, with a width of about 50cm and a length of hundreds of meters. In 2014, Japan's Asahi Glass Co., Ltd. used a float process to produce a flexible glass SPOOL with a thickness of 0.05mm. Chinese patent CN10404521B discloses a method for preparing a flexible ultra-thin glass 2. Chinese patent 201710261451.4 has disclosed a WGP polarizer.

[0047] In this embodiment, the ink frame 3, i.e., the touch circuit layer, is printed by a gravure pad printing device. Figure 3 As shown, it mainly includes an ink tank 54, a gravure cylinder 53, a pad printing cylinder 52 and a fixture 51, wherein the pad printing cylinder 52 is a rubber roller.

[0048] The ink is placed in an ink bin, and an ink roller 55 is also provided in the ink bin. The ink roller 55 contacts the gravure roller 53, and the ink roller 55 absorbs the ink in the ink bin and transfers it to the gravure of the gravure roller 53. The gravure roller 53 rotates along the direction a, and an ink scraper 56 is provided beside the gravure roller 53 to scrape off the ink in the gravure of the gravure roller 53. The gravure roller 53 transfers the ink in the gravure to the surface of the pad printing roller 52, and the pad printing roller 52 rotates along the direction b. The ultra-thin glass 2 is placed on the fixture 51 and moves along the direction c. The ultra-thin glass 2 passes under the pad printing roller 52, and the pad printing roller 52 prints the ink frame 3 on the surface of the ultra-thin glass 2. Through repeated printing, the ink frame 3 layers reach 6-8 microns. Through this gravure pad printing device, the printing efficiency is high, the thickness is uniform, and the thickness control is precise.

[0049] The printing method of the nano silver touch circuit layer 10 is the same as that of the ink frame 3, except that the pattern template of the gravure cylinder 53 is different. The nano silver touch circuit can also be made by screen printing.

[0050] In the present embodiment, each layer of the ultra-thin glass 2 protective cover plate is printed or coated without the need for optical adhesive, which not only integrates the functions of touch screen and circular polarization, but also saves the thickness and bonding process of optical adhesive, PET film, and traditional circular polarizer substrate, so that the functions of circular polarization and touch screen are integrated with the glass cover plate, making the glass cover plate with circular polarization and touch screen functions easier to fold.

[0051] In this embodiment, an anti-fouling coating 1 is preferably provided on the ultra-thin glass 2 .

[0052] A method for manufacturing a foldable ultra-thin glass cover with circular polarization and touch screen functions comprises the following steps:

[0053] 1) Printing the required ink frame 3 on the lower surface of the ultra-thin glass 2 by gravure printing, the thickness of the ink frame 3 is 6-8 microns;

[0054] 2) A layer of transparent resin coating is applied on the lower surface of the ink frame 3, with a thickness of 30-60 microns;

[0055] 3) Then, a layer of nano-scale WGP polarizer 4.2 is printed on the lower surface of the transparent resin coating. Figure 2 As shown, the specific process is as follows: first, a mold 6 having a stripe-shaped protrusion structure is used to form a groove 7 on a transparent resin coating by using nanoimprint technology; second, a metal ink 8 is filled only in the groove 7 by using a blade 9; finally, a metal grid WGP polarizer is fired in an oven;

[0056] 4) coating a layer of ¼λ phase difference film 5 below the nano-scale WGP polarizer 4.2;

[0057] 5) Printing a nanosilver circuit under the ¼λ phase difference film 5, and then performing laser dry etching trimming on the nanosilver circuit; or using ITO, first plating ITO on the lower surface of the ¼λ phase difference film 5, and then etching the ITO to form a touch circuit layer 10.

[0058] The method further includes the following step: coating an anti-fouling layer on the upper surface of the ultra-thin glass 2 , and this step is placed before step 1) or after step 5).

[0059] In the preferred step 3) of this embodiment, the material of the nano-scale WGP polarizer 4.2 (ie, the metal ink 8) is nano-silver.

[0060] By using the low reflectivity of the WGP polarizer with high durability metal, a visible light polarizer with low reflectivity and high durability is realized. The visible light wavelength ratio (400-800nm) used for the metal WGP polarizer for visible light is much finer, and the polarization characteristics are improved by making the metal grid thinner and thicker, and the line width is even finer than the 80nm verified in the past. By integrating nanoimprint technology, wet control technology, and printing technology again, thick film nanoprinting technology of metal ink 8 patterns with a line width of less than 50nm and an aspect ratio of more than 10 is realized.

[0061] In this embodiment, the transparent resin coating serves as both the explosion-proof layer 4.1 and the carrier of the nano-scale WGP polarizer 4.2, eliminating the need for optical adhesive and greatly reducing the overall thickness.

[0062] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for manufacturing a foldable ultra-thin glass cover with circular polarization and touch screen functions, characterized in that: The following steps are included: 1) Print the required ink frame on the lower surface of the ultra-thin glass by gravure printing, and the thickness of the ink frame is 6-8 microns; 2) A layer of transparent resin coating is applied on the lower surface of the ink frame with a thickness of 30-60 microns; 3) Then, a layer of nano-scale WGP polarizer is printed on the lower surface of the transparent resin coating. The specific process is as follows: first, a mold with a stripe-shaped protrusion structure is used to form grooves on the transparent resin coating using nanoimprint technology; second, a blade is used to fill only the groove part with metal ink; Finally, the metal grid WGP polarizer is fired in an oven; 4) Coating a layer of 1 / 4λ phase difference film under the nanoscale WGP polarizer; 5) Printing a nanosilver circuit under the 1 / 4λ phase difference film, and then performing laser dry etching trimming on the nanosilver circuit to form a nanosilver touch circuit layer; Or if ITO is used, ITO is first plated on the lower surface of the 1 / 4λ phase difference film, and then the ITO is etched to form a touch circuit layer; The foldable ultra-thin glass cover with circular polarization and touch screen functions manufactured by the above method comprises ultra-thin glass, an ink frame is printed below the ultra-thin glass, an explosion-proof layer is coated below the ink frame, a nano-scale WGP polarizer is printed below the explosion-proof layer, a 1 / 4λ phase difference film is coated below the nano-scale WGP polarizer, and a touch circuit layer is printed below the 1 / 4λ phase difference film; The ink frame is printed on the edge of the ultra-thin glass, and a part of the explosion-proof layer contacts the ink frame, and the other part contacts the surface of the ultra-thin glass.

2. The method for manufacturing a foldable ultra-thin glass cover with circular polarization and touch screen functions according to claim 1, characterized in that: The method further comprises the step of coating an anti-fouling layer on the upper surface of the ultra-thin glass, and this step is placed before step 1) or after step 5).

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