Protective film, cover plate and protective film removing method

Abstract

The invention relates to the technical field of display devices, and particularly provides a protective film, a cover plate and a protective film removal method.The protective film comprises a base material film layer and an adjusting adhesive layer, and the adjusting adhesive layer is located on one side of the base material film layer; wherein under a preset condition, the edge of at least one side of the adjusting adhesive layer shrinks inwards relative to the corresponding edge of the base material film layer. According to the protective film provided by the embodiment of the invention, the adjusting adhesive layer can be shrunk as required by adjusting the conditions of the protective film, and the angle-rising allowance convenient for tearing the film is formed at the edges of the adjusting adhesive layer and the base material film layer, so that the tearing difficulty of the protective film is reduced, and meanwhile, the probability of abnormal tearing when the protective film is torn is reduced.

Description

Technical Field

[0001] The present application belongs to the technical field of display devices, and more specifically, to a protective film, a cover plate, and a method for removing the protective film. Background Art

[0002] The flexible display module is the core component of the flexible display panel. In order to achieve the bendable and foldable functions, the display module has corresponding requirements for thickness and materials. Therefore, the thickness of the cover plate used is gradually reduced with the development of technology. As the thickness of the cover plate is gradually reduced, the structure of the protective film attached to the cover plate and protecting the cover plate also needs to be improved to improve its performance and make it better suitable for the cover plate after thinning. Summary of the invention

[0003] The present application provides a protective film, a cover plate and a method for removing the protective film, so as to improve the performance of the protective film at least to a certain extent.

[0004] To achieve the above-mentioned purpose, the technical solution adopted in the present application is: in the first aspect, a protective film is provided, including a substrate film layer and an adjustment adhesive layer, wherein the adjustment adhesive layer is located on one side of the substrate film layer;

[0005] Wherein, under preset conditions, at least one side edge of the regulating adhesive layer is retracted relative to the corresponding edge of the substrate film layer.

[0006] Optionally, the preset condition is that the temperature at the adjustment glue layer meets a preset temperature and after meeting the preset temperature.

[0007] Optionally, the preset temperature is not less than 150°C.

[0008] Optionally, the adjusting adhesive layer comprises an adjusting layer and an adhesive layer, and the adhesive layer is located on a side of the adjusting layer facing away from the substrate film layer.

[0009] Optionally, the thickness of the adjustment glue layer is 15 μm-30 μm.

[0010] Optionally, the adjustment layer has a thickness of 5 μm-10 μm.

[0011] Optionally, the adhesive layer has a thickness of 10 μm-20 μm.

[0012] Optionally, the adjustment layer includes a deformation adjustment layer and an auxiliary adhesive layer, and the auxiliary adhesive layer is located on a side of the deformation adjustment layer close to the substrate film layer.

[0013] Optionally, the deformation adjusting layer has a thickness of 3 μm-6 μm.

[0014] Optionally, the auxiliary adhesive layer has a thickness of 2 μm-4 μm.

[0015] Optionally, the adhesive layer is a double-sided adhesive.

[0016] Optionally, the material of the adjustment layer includes a shape memory polymer material, and the modulus of the shape memory polymer material is 100-300 MPa.

[0017] Optionally, the shape memory polymer material includes any one of an electro-memory polymer material and a thermo-memory polymer material.

[0018] Optionally, the material of the substrate film layer includes polyethylene terephthalate.

[0019] Optionally, the material of the regulating layer further includes doped particles, and the doped particles include at least one of carbon black and metal powder.

[0020] Optionally, the radius of the doped particles is in the range of 3nm-5nm.

[0021] Optionally, the ratio of the doped particles to the shape memory polymer material is 0.05‰-0.2‰, and the ratio is a mass ratio or a volume ratio.

[0022] Optionally, under preset conditions, the shrinkage ratio of the adjustment adhesive layer is not less than 5%.

[0023] Optionally, under preset conditions, the shrinkage ratio of the adjustment adhesive layer is not less than 8%.

[0024] Optionally, under preset conditions, the shrinkage ratio of the adjustment adhesive layer is no more than 20%.

[0025] Optionally, under preset conditions, the shrinkage ratio of the adjustment adhesive layer is no more than 12%.

[0026] Optionally, under preset conditions, the shrinkage ratio of the adjustment adhesive layer is 8% to 12%.

[0027] Optionally, the substrate film layer has a first side edge, and the regulating adhesive layer has a second side edge corresponding to the first side edge;

[0028] Under preset conditions, the projection of the second side edge in the thickness direction of the substrate film layer is located within the projection range of the substrate film layer in the thickness direction.

[0029] Optionally, the substrate film layer further includes a third side edge, and a corner is provided at the junction of the third side edge and the first side edge; under preset conditions, the projection of the corner in the thickness direction of the substrate film layer does not overlap with the projection of the adjusting adhesive layer in the thickness direction of the substrate film layer.

[0030] Optionally, under preset conditions, there is a distance between a projection of the first side edge in the thickness direction of the substrate film layer and a projection of the second side edge in the thickness direction of the substrate film layer, and the distance is not less than 10 mm.

[0031] Optionally, the spacing is not less than 12 mm.

[0032] Optionally, the spacing does not exceed 20 mm.

[0033] Optionally, the spacing does not exceed 18 mm.

[0034] Optionally, the spacing ranges from 12 mm to 18 mm.

[0035] Optionally, under non-preset conditions, the projected outer contour of the substrate film layer in the thickness direction of the substrate film layer and the projected outer contour of the regulating adhesive layer in the thickness direction of the substrate film layer just coincide with each other;

[0036] Under preset conditions, the projection of the regulating adhesive layer in the thickness direction of the substrate film layer is located within the projection range of the substrate film layer in the thickness direction of the substrate film layer.

[0037] In a second aspect, the present application further provides a cover plate, comprising a cover plate body and any one of the protective films described above, wherein the protective film is located on at least one side of the cover plate body in a thickness direction.

[0038] Optionally, the number of the protective films is at least two, and the protective films are provided on both sides of the cover plate body in the thickness direction.

[0039] In a third aspect, the present application further provides a protective film removal method, which is applied to the above-mentioned cover plate, and the method comprises:

[0040] Under preset conditions, a pulling force is applied to a portion of the side edge of the substrate film layer to tear the protective film off the cover plate body.

[0041] Optionally, a film-tearing tool is further included, and the film-tearing tool is used to apply the preset condition to the protective film, and / or the film-tearing tool is used to apply a tensile force to the substrate film layer.

[0042] Optionally, the method further comprises attaching a film-tearing tool to the substrate film layer.

[0043] The beneficial effects of the protective film, cover plate and protective film removal method provided by the present application are: by adjusting the conditions of the protective film, the shape of the regulating glue layer in the protective film is changed, so that the regulating glue layer shrinks when needed, and at this time, a certain step difference appears between the substrate film layer and the regulating glue layer in the protective film, and a corner margin that is convenient for film tearing can be formed, achieving the effect of reducing the difficulty of cornering, and can effectively reduce the difficulty of tearing the protective film, so as to achieve the purpose of convenient and quick removal of the protective film relative to the cover plate, and reduce the probability of abnormal film tearing during the protective film removal process. For the cover plate and the display module, the above-mentioned protective film structure helps to improve the production yield and efficiency of the display module. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0045] Figure 1 A schematic diagram of the structure of the protective film provided in an embodiment of the present application under non-preset conditions;

[0046] Figure 2 A schematic diagram of the structure of the protective film provided in an embodiment of the present application under preset conditions;

[0047] Figure 3 for Figure 2 A top view of

[0048] Figure 4 Another schematic diagram of the structure of the protective film provided in an embodiment of the present application under preset conditions;

[0049] Figure 5 for Figure 4 A magnified view of the structure in the middle A area;

[0050] Figure 6 for Figure 4 A top view of

[0051] Figure 7 A schematic diagram of the structure of a protective film provided in another embodiment of the present application under non-preset conditions;

[0052] Figure 8 for Figure 7 A cross-sectional view of the adjustment glue layer in FIG.

[0053] Fig. 9 A schematic diagram of the structure of the cover plate provided in an embodiment of the present application;

[0054] Fig.10Another schematic diagram of the structure of the cover plate provided in the embodiment of the present application;

[0055] Fig.11 A schematic diagram of a process for removing a protective film provided in an embodiment of the present application;

[0056] Fig.12 This is a schematic diagram of the state of the cover plate provided in an embodiment of the present application when the protective film is torn off.

[0057] Among them, the reference numerals in the figure are:

[0058] 1. Base film layer; 101. First side edge; 102. Third side edge; 103. Corner; 2. Adjustment adhesive layer; 21. Adjustment layer; 211. Doped particles; 2101. Deformation adjustment layer; 2102. Auxiliary adhesive layer; 22. Adhesion layer; 201. Second side edge; 202. Thickening portion; 10. Protective film; 100. Cover plate; 20. Cover plate body. DETAILED DESCRIPTION

[0059] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0060] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0061] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0062] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0063] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0064] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0065] In the present application, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0066] With the development of display technology, the types of display panels in the market are gradually increasing, and the performance is constantly improving. In order to meet the personalized needs of different devices, such as folding products, some display panels need to be thinned. Taking a display module with a flexible cover as an example, in order to meet the needs of folding products, some modules in the display module need to be thinned to a certain extent, taking the thinning of the flexible cover as an example. In the process of thinning the thickness of the flexible cover, the inventor found the following problem. As the thickness of the cover is thinned, the difficulty of controlling the warping of the cover gradually increases, especially during the storage and transportation of the cover. In order to overcome this problem, it is necessary to thicken the protective film to balance the warping of the cover and improve the yield of the cover. However, in the production stage, an overly thick protective film will cause difficulties in the film tearing process, resulting in an increase in the abnormal rate of film tearing, and ultimately affecting the production yield and production efficiency of the display module.

[0067] Based on this, an embodiment of the present application provides a protective film 10, which is suitable for a cover plate 100 and other similar products to help improve the above-mentioned problems.

[0068] Specifically, the protective film 10 includes a substrate film layer 1 and an adjustment adhesive layer 2, and the adjustment adhesive layer 2 is located on one side of the substrate film layer 1. Figure 1-Figure 3 , under preset conditions, at least one side edge of the adhesive layer 2 is adjusted to be retracted relative to the corresponding edge of the substrate film layer 1 .

[0069] When the protective film 10 is used to protect the corresponding device, the cover plate 100 is taken as an example. The protective film 10 can be attached to the surface of the cover plate 100 by adjusting the adhesive layer 2. At this time, the protective film 10 can provide a certain protection for the surface of the cover plate 100 to prevent the cover plate 100 from being damaged before use or being polluted by the external environment.

[0070] See also Figure 1 The substrate film layer 1 and the adjustment adhesive layer 2 are stacked in the thickness direction, and the substrate film layer 1 can be attached to the corresponding device surface through the adjustment adhesive layer 2. At this time, the substrate film layer 1 can play a role in protecting the device. For example, the substrate film layer 1 can prevent external hard objects from acting on the surface of the protected device, and prevent scratches on the device surface.

[0071] Specifically, the material of the substrate film layer 1 includes polyethylene terephthalate (PET for short). PET has high transparency, high strength and good barrier properties, and can provide good protection for the cover plate 100 and the like.

[0072] Specifically, the material of the above-mentioned adjustment adhesive layer 2 includes shape memory polymers (SMP for short). SMP refers to a product with an initial shape, which can restore its original shape under the stimulation of external conditions (such as heat, electricity, light, chemical induction, etc.) after its initial condition is changed and fixed under certain conditions.

[0073] In this embodiment, the SMP can restore its original shape under preset conditions, which is manifested as shrinkage relative to the substrate film layer 1 . And finally, at least one side edge of the regulating adhesive layer 2 shrinks relative to the corresponding edge of the substrate film layer 1 .

[0074] When the adjustment adhesive layer 2 shrinks under the preset conditions, its edge will shrink relative to the corresponding edge of the substrate film layer 1, and the edge of the adjustment adhesive layer 2 will be in an inward retreat state relative to the edge of the substrate film layer 1. Figure 2 At this time, a certain step difference is generated between the edge of the substrate film layer 1 and the edge of the regulating adhesive layer 2 , and the step difference can form an angle margin for tearing off the protective film 10 , so as to reduce the difficulty of tearing off the protective film 10 .

[0075] Under preset conditions, the protective film 10 can reduce the difficulty of cornering through the retractable adjustment adhesive layer 2. After forming a cornering margin for convenient force application on the protective film 10, the operator can quickly tear off the protective film 10 by applying tension to the cornering area.

[0076] Of course, considering the transportation and storage of the protective film 10 itself, the protective film 10 can be provided with a release film that is easy to remove, and the release film is located on the side of the adjustment adhesive layer 2 facing away from the substrate film layer 1. Alternatively, the protective film 10 can also be directly processed on the surface of the device to be protected (such as the cover plate 100), in which case the protective film 10 does not need to be provided with the above-mentioned release film structure.

[0077] In this embodiment, the preset condition for controlling and adjusting the shrinkage of the adhesive layer 2 is that the temperature at the adhesive layer 2 meets the preset temperature and after the preset temperature is met.

[0078] The preset temperature is not less than 150°C.

[0079] Specifically, in some embodiments, the preset condition may be to adjust the temperature of the adhesive layer 2 to 150° C. or 160° C. It should be noted that the temperature should be controlled not to exceed the melting temperature of the relevant film layer and the relevant device to avoid damage to the film layer and the relevant device.

[0080] By treating the above-mentioned adjusting adhesive layer 2 under the condition of satisfying the preset temperature, the adjusting adhesive layer 2 can be made to shrink and retreat inward relative to the substrate film layer 1, so as to more easily form a starting angle for tearing.

[0081] In some embodiments, the shrinkage ratio of the adjustment adhesive layer 2 under preset conditions is not less than 5%; and / or the shrinkage ratio is not greater than 20%.

[0082] Specifically, the shrinkage ratio may be set to be no less than 8%; and / or no more than 12%.

[0083] That is to say, the shrinkage ratio of the adhesive layer 2 under the preset conditions can be controlled within the range of 8% to 12%, and the specific numerical range can be adjusted according to actual needs.

[0084] For example, the shrinkage ratio of the adhesive layer 2 under the preset conditions can be adjusted to any value among 85%, 9%, 10%, 11%, 12% and the like.

[0085] Taking a side edge of the substrate film layer 1 in the extension direction as an example, the relative state change process of the substrate film layer 1 and the adjustment adhesive layer 2 under non-preset conditions and preset conditions is described below.

[0086] Definition: The substrate film layer 1 has a first side edge 101 at one end in the extension direction, and the adjustment adhesive layer 2 has a second side edge 201 at the same end, and the first side edge 101 corresponds to the second side edge 201. Under the preset conditions, the adjustment adhesive layer 2 shrinks, and the second side edge 201 will retreat inward toward the center relative to the first side edge 101 as the adjustment adhesive layer 2 shrinks. Please refer to Figure 2 At this time, the projection of the second side edge 201 in the thickness direction of the substrate film layer 1 is located within the projection range of the substrate film layer 1 in the thickness direction.

[0087] Specifically, under non-preset conditions, the first side edge 101 and the second side edge 201 in the substrate film layer 1 can be arranged exactly opposite to each other. At this time, the projection contour of the first side edge 101 in the thickness direction of the substrate film layer 1 overlaps with the projection contour of the second side edge 201 in the thickness direction of the substrate film layer 1. Figure 1 Of course, there is also a case where the size of the substrate film layer 1 is larger than the size of the regulating adhesive layer 2. This embodiment does not limit this.

[0088] The non-preset condition means that the temperature of the adjustment adhesive layer 2 is always lower than the preset temperature, and the adjustment adhesive layer 2 maintains the initial shape and does not deform.

[0089] It should be noted that after the adjustment adhesive layer 2 shrinks under the preset conditions, the shrinkage state will continue to be maintained. In other words, when the temperature of the adjustment adhesive layer 2 that has shrunk gradually decreases to below the preset temperature (i.e., after the preset temperature condition is not met), the adjustment adhesive layer 2 can always maintain its shrinkage state and will not return to the unshrinkage state as the temperature decreases. Therefore, all the non-preset conditions mentioned above should be understood as the adjustment adhesive layer 2 not shrinking at this time.

[0090] In the following, the embodiment of the present application only describes the structure in which the protective film 10 is an integrally cut film. In this case, the shapes and sizes of the base film layer 1 and the regulating adhesive layer 2 in the protective film 10 are consistent, and the side edges are exactly opposite.

[0091] Under non-preset conditions, the projected outer contour of the substrate film layer 1 in the thickness direction of the substrate film layer 1 coincides with the projected outer contour of the adjusting adhesive layer 2 in the thickness direction of the substrate film layer 1. Under preset conditions, the adjusting adhesive layer 2 will shrink relative to the substrate film layer 1, and the outer contour of the adjusting adhesive layer 2 will retreat inward relative to the outer contour of the substrate film layer 1.

[0092] See also Figure 3 , the projection of the above-mentioned regulating adhesive layer 2 in the thickness direction of the substrate film layer 1 is located within the projection range of the substrate film layer 1 in the thickness direction of the substrate film layer 1 . Figure 3 The dotted line portion in represents the outer contour of the adjustment glue layer 2.

[0093] After the adjustment adhesive layer 2 shrinks relative to the base film layer 1 and retreats to a certain extent, there is a certain distance between the projection contour formed by the first side edge 101 in the projection of the base film layer 1 in the thickness direction and the projection contour formed by the second side edge 201 in the projection of the adjustment adhesive layer 2 in the thickness direction. This distance is d, and its position and size can be found in Figure 3 .

[0094] In some embodiments, under preset conditions, there is a distance d between the projection of the first side edge 101 in the thickness direction of the substrate film layer 1 and the projection of the second side edge 201 in the thickness direction of the substrate film layer 1 , and the distance d is not less than 10 mm.

[0095] The above distance is the length of the adjustment adhesive layer 2 to shrink relative to the corresponding edge of the substrate film layer 1. Taking the first side edge 101 and the second side edge 201 as an example, the distance is the length of the second side edge 201 to shrink relative to the first side edge 101.

[0096] Of course, the other side edges of the protective film 10 at other positions may also have the edge of the adjusting adhesive layer 2 retreated relative to the substrate film layer 1. For example, when the protective film 10 is a rectangular structure with a certain thickness, the substrate film layer 1 and the adjusting adhesive layer 2 are both rectangular, and the adjusting adhesive layer 2 will shrink under preset conditions to form a rectangle slightly smaller than the substrate film layer 1. At this time, there is a gap between the four side edges of the substrate film layer 1 and the corresponding side edges of the adjusting adhesive layer 2. Of course, the above-mentioned protective film 10 can also be a rounded rectangle or a strip structure, and accordingly, the shape and size of the substrate film layer 1 and the adjusting adhesive layer 2 will also be adjusted accordingly. This embodiment does not limit the specific shape and size of the above-mentioned protective film 10.

[0097] In some embodiments, taking the interval formed between the first side edge 101 and the second side edge 201 as an example, the size of the interval may be limited to not more than 20 mm, and in this case, the size range of the interval is 10 mm-20 mm.

[0098] Specifically, the size of the above-mentioned spacing may be limited to not less than 12 mm, and in this case, the spacing ranges from 12 mm to 20 mm.

[0099] Specifically, the above spacing can be further limited to not more than 18 mm. In this case, the spacing can be limited to within the range of 12 mm-18 mm, and the specific numerical range can be adjusted according to actual needs.

[0100] For example, the spacing may be any value among 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, etc.

[0101] Under normal circumstances, each position of the adjustment glue layer 2 should shrink evenly under preset conditions to form a tearing margin that is convenient for operation between the edge of the adjustment glue layer 2 and the corresponding edge of the substrate film layer 1. In some special cases, for example, different areas of the adjustment glue layer 2 shrink unevenly, please refer to Figure 4 and Figure 5 After the partial adjustment adhesive layer 2 shrinks under the preset conditions, the film layer at the edge portion may become thicker and form a thickened portion 202 .

[0102] At this time, due to the lifting effect of the thickened portion 202, the substrate film layer 1 opposite to the thickened portion 202 in the thickness direction will bend toward the side facing away from the adjustment adhesive layer 2, and drive the side edge of the substrate film layer 1 adjacent to the thickened portion 202 to deviate toward the side facing away from the adjustment adhesive layer 2, see Figure 5 .

[0103] If the edge of the substrate film layer 1 adjacent to the thickened portion 202 is warped, the step difference between the edge of the substrate film layer 1 and the edge of the adjusting adhesive layer 2 can be further increased on the premise that a warping margin is formed between the substrate film layer 1 and the adjusting adhesive layer 2, thereby reducing the difficulty of warping and ultimately achieving the effect of reducing the difficulty of film tearing.

[0104] See also Figure 6 The substrate film layer 1 further includes a third side edge 102 connected to the first side edge 101. A corner 103 is formed where the first side edge 101 and the third side edge 102 are connected.

[0105] Under non-preset conditions, the projection of the corner 103 formed by the intersection of the first side edge 101 and the third side edge 102 in the thickness direction of the substrate film layer 1 (that is, the thickness direction of the protective film 10 itself) can coincide with the projection of the adjustment adhesive layer 2 in the thickness direction of the substrate film layer 1, which is manifested as the projection of the corner 103 just falling on the projection contour line of the corresponding position of the substrate film layer 1.

[0106] Under the preset conditions, the adjustment adhesive layer 2 shrinks, resulting in a smaller projection range, while the projection position of the corner 103 remains unchanged, resulting in the projection of the corner 103 in the thickness direction of the substrate film layer 1 being located outside the projection of the adjustment adhesive layer 2 in the thickness direction of the substrate film layer 1, see Figure 6 At this time, the projection of the corner portion 103 in the thickness direction of the substrate film layer 1 does not overlap with the projection of the adjustment adhesive layer 2 in the thickness direction of the substrate film layer 1 , and there is a certain distance between the two.

[0107] After the thickened portion 202 is formed on the adjustment adhesive layer 2 , the first side edge 101 and the third side edge 102 can both be lifted relative to the adjustment adhesive layer 2 , and the angle 103 at the intersection of the first side edge 101 and the third side edge 102 has the largest lift.

[0108] When the intersecting first side edge 101 and second side edge 201 are both warped relative to the substrate film layer 1, a local stress concentration area will be formed at the intersection (i.e., corner 103), and the warping amplitude of the corner 103 will be larger. At this time, the bending deformation degree of the corner 103 is greater than the bending deformation degree of the first side edge 101 and the second side edge 201. Therefore, the warping of the corner 103 can provide a better starting point for the removal operation of the protective film 10, making the removal process of the protective film 10 easier.

[0109] When an operator needs to remove the protective film 10 , the slight warping of the corner 103 can make it easier for the operator to find the operating position, thereby reducing the difficulty of the operation.

[0110] The structure and composition of the above-mentioned regulating adhesive layer 2 are described in detail below.

[0111] In some embodiments, the adjustment adhesive layer 2 is a double-layer film layer, including an adjustment layer 21 and an adhesive layer 22, wherein the adjustment layer 21 is located on one side of the substrate film layer 1, and the adhesive layer 22 is located on the side of the adjustment layer 21 facing away from the substrate film layer 1, see Figure 7 .

[0112] The adhesive layer 22 is used to provide adhesion so as to be attached to the surface of the device to be protected. In this case, the substrate film layer 1 can play a role in protecting the device.

[0113] In some embodiments, the adhesive layer 22 may be a double-sided adhesive.

[0114] Double-sided differential adhesive is an adhesive with different peeling forces on both sides, with one side having relatively high adhesive force and the other side having relatively low adhesive force. In this embodiment, the side with low adhesive force of the adhesive layer 22 is used to contact the device to be attached and protected, and the side with high adhesive force is used to adhere to the adjustment layer 21, so as to ensure that the adhesive layer 22 can be firmly combined with the substrate film layer 1 through the adjustment layer 21, and can shrink synchronously with the shrinkage of the adjustment layer 21 under preset conditions, so that the edge of the adjustment adhesive layer 2 can shrink relative to the corresponding edge of the substrate film layer 1; at the same time, it is more convenient to tear off the substrate film layer 1 from the surface of the protected device.

[0115] Specifically, the adhesive force of the adhesive layer 22 facing the adjustment layer 21 is not less than 1000 gF / mm, and the adhesive force of the adhesive layer 22 facing away from the adjustment layer 21 is 3 gF / mm-20 gF / mm.

[0116] In some embodiments, the adhesive layer 22 may include acrylic adhesive, the specific components of which have been disclosed in the relevant art and will not be described in detail here.

[0117] The adjustment layer 21 is located between the adhesive layer 22 and the substrate film layer 1 , and the shape memory polymer (ie, SMP, hereinafter directly referred to as SMP) is distributed in the adjustment layer 21 .

[0118] As a high molecular polymer, SMP can achieve deformation and recovery under certain conditions. Its mechanism of action is based on the structural characteristics of the fixed phase and reversible phase inside the material, as well as the movement and interaction of molecular chains. SMP can be divided into thermo-induced, electro-induced, photo-induced, chemical-induced, etc. according to its deformation and recovery principles.

[0119] The deformation process of SMP materials mainly includes two stages: shape programming (deformation and fixation) and shape recovery. In the shape programming stage, it mainly includes three stages: heating softening, deformation and cooling fixation:

[0120] (1) Heating and softening

[0121] SMP needs to be heated to a specific temperature, which is usually higher than the glass transition temperature or melting point of the material. When the temperature reaches this range, the microscopic Brownian motion of the reversible phase molecular chain in SMP intensifies, the molecular chain segments change from a frozen state to a relatively free motion state, and the material changes from a glassy state to a rubbery state, showing a certain fluidity as a whole, similar to the state of rubber at high temperature.

[0122] (2) Deformation by applying external force

[0123] When the material is in a softened state, an external force can be applied to it to stretch and orient the molecular chains of the reversible phase, deforming the material to form a temporary shape different from the initial shape. For example, an SMP rod can be bent to a specific angle, or an SMP film can be stretched into a specific shape.

[0124] (3) Cooling and fixing

[0125] The material is cooled while maintaining the external force. During the cooling process, the reversible phase undergoes crystallization or glass transition, the movement of the molecular chain is frozen again, and the material hardens, thereby fixing the deformed shape. At this point, even if the external force is removed, the material can still maintain the deformed shape.

[0126] The shape recovery stage mainly includes the stimulus triggering process. When a specific external stimulus is applied to the SMP that has completed shape programming, the material begins to recover to its initial shape. At this time, the molecular chains of the reversible phase gradually release their orientation and return to their original random curling state. At the same time, the stationary phase plays a role in maintaining the stability of the overall structure of the material and memorizing the initial shape, guiding the molecular chains of the reversible phase to move in the direction of the initial shape. With the movement of the molecular chains, the material gradually recovers to its initial shape on a macroscopic scale.

[0127] Common stimulation methods include thermal stimulation, electrical stimulation, optical stimulation and chemical stimulation. For example, for thermotropic SMP, when heated to a certain temperature (usually higher than the temperature during shape programming or reaching the shape recovery temperature of the material), the molecular structure and interaction inside the material change, triggering the shape recovery process; for electrotropic SMP, the material generates heat by passing current, thereby reaching the temperature condition for shape recovery; for phototropic SMP, the photochromic groups in the material undergo photoisomerization reaction under the irradiation of ultraviolet light or visible light, causing the state of the molecular chain to change, resulting in shape recovery.

[0128] The structure of the adjustment layer 21 having the above-mentioned SMP material can be found in Figure 8 , wherein the modulus of the SMP material is 100-300 MPa, and the material of the adjustment layer 21 includes the above-mentioned SMP.

[0129] In some embodiments, the SMP material may be an electrotropic SMP material or a thermotropic SMP material.

[0130] In order to meet the use requirements of the protective film 10, in some embodiments, the thickness of the adhesive layer 2 can be adjusted to a range of 15 μm-30 μm, and the specific value range can be adjusted according to actual needs.

[0131] For example, the thickness of the adhesive layer 2 can be adjusted to any value of 15μm, 16μm, 17μm, 18μm, 19μm, 20μm, 21μm, 22μm, 23μm, 24μm, 25μm, 26μm, 27μm, 28μm, 29μm, 30μm, etc.

[0132] Since the adjustment glue layer 2 is a double-layer structure, the thickness of the adjustment layer 21 in the adjustment glue layer 2 can be set to be in the range of 5 μm-10 μm, and correspondingly, the thickness of the adhesive layer 22 can be set to be in the range of 10 μm-20 μm. Figure 7 In the figure, d1 is used to indicate the thickness of the adjustment layer 21, and d2 is used to indicate the thickness of the adhesive layer 22.

[0133] When the thickness of the adjustment layer 21 is 5μm, the thickness of the adhesive layer 22 can be any value between 10μm and 20μm; when the thickness of the adjustment layer 21 is 6μm, the thickness of the adhesive layer 22 can be any value between 10μm and 19μm; when the thickness of the adjustment layer 21 is 7μm, the thickness of the adhesive layer 22 can be any value between 10μm and 18μm; when the thickness of the adjustment layer 21 is 8μm, the thickness of the adhesive layer 22 can be any value between 10μm and 17μm; when the thickness of the adjustment layer 21 is 9μm, the thickness of the adhesive layer 22 can be any value between 10μm and 16μm; when the thickness of the adjustment layer 21 is 10μm, the thickness of the adhesive layer 22 can be any value between 10μm and 15μm.

[0134] In some embodiments, in order to further ensure that the adjustment layer 21 can be firmly combined with the substrate film layer 1, the adjustment layer 21 is a double-layer structure, including a deformation adjustment layer 2101 and an auxiliary adhesive layer 2102. Figure 8 .

[0135] The deformation adjustment layer 2101 includes the shape memory polymer material described above, and the auxiliary adhesive layer 2102 is located between the deformation adjustment layer 2101 and the substrate film layer 1, that is, the side of the deformation adjustment layer 2101 close to the substrate film layer 1. The auxiliary adhesive layer 2102 is used to achieve adhesion between the deformation adjustment layer 2101 and the substrate film layer 1.

[0136] In this embodiment, the thickness of the deformation adjustment layer 2101 is 3 μm-6 μm, and correspondingly, the thickness of the auxiliary adhesive layer 2102 is 2 μm-4 μm. The specific value range can be adjusted according to actual needs.

[0137] When the thickness of the deformation adjustment layer 2101 is 3μm, the thickness of the auxiliary adhesive layer 2102 can be any value among 2μm, 3μm, and 4μm; when the thickness of the deformation adjustment layer 2101 is 4μm, the thickness of the auxiliary adhesive layer 2102 can be any value among 2μm, 3μm, and 4μm; when the thickness of the deformation adjustment layer 2101 is 5μm, the thickness of the auxiliary adhesive layer 2102 can be any value among 2μm, 3μm, and 4μm; when the thickness of the deformation adjustment layer 2101 is 6μm, the thickness of the auxiliary adhesive layer 2102 can be any value among 2μm, 3μm, and 4μm.

[0138] In some embodiments, the deformation adjustment layer 2101 having SMP material further includes doped particles 211. The doped particles 211 can be used to improve the electrical conductivity of the deformation adjustment layer 2101. For electro-type SMP, the doped particles 211 can make the deformation adjustment layer 2101 have a certain conductivity, so that the SMP can trigger shape recovery under electrical stimulation, rather than relying solely on thermal stimulation. For example, when an electric current is applied to an SMP doped with carbon black, the current generates heat through the conductive network formed by the carbon black particles, which increases the material temperature, thereby inducing shape recovery, and can improve the deformation recovery rate of the adjustment glue layer 2.

[0139] Of course, the doped particles 211 can also improve the mechanical properties of the SMP material.

[0140] Specifically, the doped particles 211 include at least one of carbon black and metal powder, wherein the metal powder may be at least one of copper powder, aluminum powder, iron powder, and nickel powder.

[0141] Of course, other conductive materials such as graphene, carbon nanotubes, etc. may also be selected as the doping particles 211 as needed.

[0142] The radius of the doped particles 211 is in the range of 3 nm to 5 nm. This radius range can be understood as the radius of all the doped particles 211 meeting the requirements of this range, or it can be understood as the average radius of the doped particles 211 meeting the requirements of this range.

[0143] In this example, see Figure 8 The ratio of the doped particles 211 to the shape memory polymer material is 0.05‰-0.2‰, and its specific numerical range can be adjusted according to actual needs. For example, the ratio can be any value among 0.05‰, 0.10‰, 0.15‰, 0.20‰, etc.

[0144] Specifically, the above ratio is a volume ratio. Of course, in other similar embodiments, the ratio may also be a mass ratio.

[0145] For clarity of illustration, Figure 8 The size of the doping particles 211 distributed within the deformation adjusting layer 2101 may be exaggerated.

[0146] The deformation adjustment layer 2101 having the above-mentioned SMP material and doped particles 211 can be attached to the substrate film layer 1 at room temperature without deformation; when the deformation adjustment layer 2101 in the protective film 10 is in a powered state, the electric charge can move in the SMP material and drive the material to generate heat. When the heat in the deformation adjustment layer 2101 meets the preset conditions, the SMP shrinks and drives the auxiliary adhesive layer 2102 and the adhesive layer 22 attached thereto to shrink synchronously, which is manifested in the macroscopic view that the edge of the adjustment adhesive layer 2 shrinks relative to the edge of the substrate film layer 1.

[0147] It can be understood that the protective film 10 provided in the embodiment of the present application adjusts the conditions in which the protective film 10 is located, changes the shape of the regulating adhesive layer 2 in the protective film 10, and makes the regulating adhesive layer 2 shrink when needed. At this time, a certain step difference appears between the substrate film layer 1 and the regulating adhesive layer 2 in the protective film 10, and a corner margin that is convenient for film tearing can be formed, thereby achieving the effect of reducing the difficulty of cornering, helping to solve the anti-release problem when tearing the film, and effectively reducing the difficulty of tearing the protective film 10. When the protective film 10 needs to be removed from the surface of the protected object, its operation is relatively convenient, and the probability of abnormal film tearing during the removal of the protective film 10 can be greatly reduced, so that the protective film 10 can be removed smoothly.

[0148] In a second aspect, the present application also provides a cover plate 100, see Fig. 9 and Fig.10 .

[0149] The cover plate 100 includes a cover plate body 20 and the aforementioned protective film 10, wherein the protective film 10 is located on at least one side in the thickness direction of the cover plate body 20. The structure and properties of the protective film 10 can be referred to above and will not be repeated here.

[0150] See also Fig. 9 , a protective film 10 is attached to the upper surface of the cover body 20; please refer to Fig.10 In the figure, the upper and lower surfaces of the cover body 20 are both attached with a protective film 10. The protective film 10 is attached to the surface of the cover body 20 by adjusting the adhesive layer 2.

[0151] When the protective films 10 are disposed on both sides of the cover body 20 in the thickness direction, the number of the protective films 10 is at least two.

[0152] Generally speaking, the size of the protective film 10 should not be smaller than the size of the corresponding surface of the cover body 20 . In this case, there is only one protective film 10 on the corresponding surface of the cover body 20 .

[0153] Since the cover plate 100 provided in the embodiment of the present application includes the above-mentioned protective film 10, the cover plate 100 at least includes the beneficial effects of any one or several of the above-mentioned protective films 10. The specific effects refer to the specific description in the above-mentioned embodiment and will not be repeated here.

[0154] When the cover body 20 is assembled on the corresponding display module, the protective film 10 attached to at least one side of the surface of the cover body 20 needs to be removed.

[0155] In a third aspect, an embodiment of the present application further provides a method for removing a protective film 10 , which is applied to remove the above-mentioned cover body 20 and other devices to which the protective film 10 is attached.

[0156] The method includes the following steps:

[0157] Step S10 : Under preset conditions, a pulling force is applied to a portion of the side edge of the substrate film layer 1 to tear the protective film 10 off the cover plate body 20 .

[0158] When removing a cover body 20 or other similar structure having two protective films 10, the two protective films 10 can be removed in sequence, or the protective film 10 on one side of the cover body 20 can be removed first, and after completing the required pretreatment of the cover body 20, the protective film 10 on the other side of the cover body 20 can be removed according to the requirements of the process.

[0159] The method further comprises a film-tearing tool, which is used to provide a preset condition to the protective film 10 , and / or the film-tearing tool is used to apply a tensile force to the substrate film layer 1 .

[0160] See also Fig.11 The step S10 for tearing off the protective film 10 includes:

[0161] Step S11, providing preset conditions to the protective film 10 by using a film-tearing tool;

[0162] Step S12 : applying a pulling force to the base film layer 1 of the protective film 10 by using a film-tearing tool to tear the protective film 10 off the cover plate body 20 .

[0163] In step S11, the film tearing tool provides preset conditions to the protective film 10, which can be understood as follows: the film tearing tool is connected to the protective film 10 and forms a power-on circuit, at which time the protective film 10 is in a power-on state and can be heated to meet the preset temperature; or, the film tearing tool releases heat, at which time the protective film 10 is heated by the heat released by the film tearing tool to meet the preset temperature.

[0164] In step S12, the film-tearing tool applies a pulling force to the substrate film layer 1 of the protective film 10, which can be understood as the film-tearing tool can be bonded to the substrate film layer 1 of the protective film 10. Under the action of the bonding force, the force applied to the film-tearing tool and used to drive the film-tearing tool to move can act on the substrate film layer 1 and pull the substrate film layer 1 to move.

[0165] Specifically, the film tearing tool is a film tearing roller, and its structure is prior art and will not be described in detail here.

[0166] When the protective film 10 is removed from the cover body 20, its appearance is as follows: Fig.12 It can be seen that at this time, the adjustment adhesive layer 2 is retracted relative to the substrate film layer 1 , and as the protective film 10 is removed, a portion of the edge of the protective film 10 is separated from the surface of the cover body 20 .

[0167] It should be noted that after removing the protective film 10 adhered to the surface of the cover plate 100 , the protective film 10 will not cause any impact on the cover plate 100 , and the regulating adhesive layer 2 of the protective film 10 , especially the adhesive layer 22 , will not remain on the surface of the cover plate 100 .

[0168] In some embodiments, when the film-tearing tool applies a pulling force to the substrate film layer 1 of the protective film 10 , the temperature of the film-tearing tool should be reduced to room temperature to prevent workers from getting burned and improve the safety of the operation.

[0169] In order to facilitate the workers to perform the film tearing operation, in some embodiments, a tearing position can be provided on the surface of the substrate film layer 1 facing away from the regulating adhesive layer 2, and a pulling force can be applied to the tearing position to achieve smooth tearing of the protective film 10.

[0170] In some embodiments, as mentioned above, the tearing position may be set at a certain area of ​​the first side edge 101 of the substrate film layer 1 or a partial area of ​​the substrate film layer 1 adjacent to the first side edge 101 .

[0171] Under preset conditions, the first side edge 101 of the substrate film layer 1 can be adjusted to form a corner margin corresponding to the adhesive layer 2. The corner margin can provide a certain convenience for tearing off the protective film 10. When a part of the corner margin is used as a film tearing position to be attached to the film tearing tool and used as the starting point of film tearing, the difficulty of peeling off the film can be effectively reduced, so that the protective film 10 can be torn off from the surface of the cover body 20 smoothly and quickly.

[0172] Specifically, the tear-off position may be disposed adjacent to the middle of the first side edge 101 , or the tear-off position may be disposed at the corner 103 mentioned above.

[0173] It should be noted that the method further includes, before executing step S10 , attaching the film-tearing tool to the substrate film layer 1 .

[0174] It is understandable that the method for removing the protective film 10 provided in the embodiment of the present application is applicable to the cover plate 100 and other similar electronic devices to which the protective film 10 is attached. The method can change the shape of the regulating adhesive layer 2 in the protective film 10 by adjusting the conditions in which the protective film 10 is located, so that the regulating adhesive layer 2 shrinks when needed. At this time, a certain step difference appears between the substrate film layer 1 and the regulating adhesive layer 2 in the protective film 10, and a corner margin that is convenient for film tearing can be formed, achieving the effect of reducing the difficulty of corner tearing, and can effectively reduce the difficulty of tearing the protective film 10, so as to achieve the purpose of convenient and quick removal of the protective film 10 relative to the cover plate 100, and reduce the probability of abnormal film tearing during the removal of the protective film 10.

[0175] For the cover plate 100 and the display module having the cover plate 100 , the method for removing the protective film 10 is also helpful to improve the production yield and efficiency of the display module.

[0176] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A protective film, characterized in that: include: A substrate film layer (1); An adjustment adhesive layer (2) is located on one side of the substrate film layer (1); Wherein, under preset conditions, at least one side edge of the regulating adhesive layer (2) is retracted relative to the corresponding edge of the substrate film layer (1).

2. The protective film according to claim 1, characterized in that: The preset condition is that the temperature at the adjustment adhesive layer (2) meets the preset temperature and after meeting the preset temperature; Preferably, the preset temperature is not lower than 150°C.

3. The protective film according to claim 1, characterized in that: The adjusting adhesive layer (2) comprises an adjusting layer (21) and an adhesive layer (22), wherein the adhesive layer (22) is located on a side of the adjusting layer (21) facing away from the substrate film layer (1); Preferably, the thickness of the adjustment glue layer (2) is 15 μm-30 μm; Preferably, the thickness of the adjustment layer (21) is 5 μm-10 μm; Preferably, the thickness of the adhesive layer (22) is 10 μm-20 μm; Preferably, the adjustment layer (21) comprises a deformation adjustment layer (2101) and an auxiliary adhesive layer (2102), and the auxiliary adhesive layer (2102) is located on a side of the deformation adjustment layer (2101) close to the substrate film layer (1); Preferably, the thickness of the deformation adjustment layer (2101) is 3 μm-6 μm; Preferably, the thickness of the auxiliary adhesive layer (2102) is 2 μm-4 μm; Preferably, the adhesive layer (22) is a double-sided adhesive.

4. The protective film according to claim 3, characterized in that: The material of the adjustment layer (21) comprises a shape memory polymer material, and the modulus of the shape memory polymer material is 100-300 MPa; Preferably, the shape memory polymer material includes any one of an electro-memory polymer material and a thermal memory polymer material; Preferably, the material of the substrate film layer (1) includes polyethylene terephthalate; Preferably, the material of the adjustment layer (21) further comprises doped particles (211), and the doped particles (211) comprise at least one of carbon black and metal powder; Preferably, the radius of the doped particles (211) is in the range of 3nm-5nm; Preferably, the ratio of the doped particles (211) to the shape memory polymer material is 0.05‰-0.2‰, and the ratio is a mass ratio or a volume ratio.

5. The protective film according to claim 4, characterized in that: Under preset conditions, the shrinkage ratio of the regulating adhesive layer (2) is not less than 5%; Preferably, under preset conditions, the shrinkage ratio of the adjustment adhesive layer (2) is not less than 8%; Preferably, under preset conditions, the shrinkage ratio of the adjustment adhesive layer (2) is no greater than 20%; Preferably, under preset conditions, the shrinkage ratio of the adjustment adhesive layer (2) is no greater than 12%; Preferably, under preset conditions, the shrinkage ratio of the adjustment adhesive layer (2) is 8% to 12%.

6. The protective film according to claim 1, characterized in that: The substrate film layer (1) has a first side edge (101), and the regulating adhesive layer (2) has a second side edge (201) corresponding to the first side edge (101); Under preset conditions, the projection of the second side edge (201) in the thickness direction of the substrate film layer (1) is located within the projection range of the substrate film layer (1) in the thickness direction; Preferably, the substrate film layer (1) further comprises a third side edge (102), and a corner portion (103) is provided at the junction of the third side edge (102) and the first side edge (101), and under preset conditions, a projection of the corner portion (103) in the thickness direction of the substrate film layer (1) does not overlap with a projection of the regulating adhesive layer (2) in the thickness direction of the substrate film layer (1); Preferably, under preset conditions, there is a distance between the projection of the first side edge (101) in the thickness direction of the substrate film layer (1) and the projection of the second side edge (201) in the thickness direction of the substrate film layer (1), and the distance is not less than 10 mm; Preferably, the spacing is not less than 12 mm; Preferably, the spacing does not exceed 20 mm; Preferably, the spacing does not exceed 18 mm; Preferably, the spacing ranges from 12 mm to 18 mm.

7. The protective film according to claim 1, characterized in that: Under non-preset conditions, the projected outer contour of the substrate film layer (1) in the thickness direction of the substrate film layer (1) and the projected outer contour of the regulating adhesive layer (2) in the thickness direction of the substrate film layer (1) exactly coincide with each other; Under preset conditions, the projection of the regulating adhesive layer (2) in the thickness direction of the substrate film layer (1) is located within the projection range of the substrate film layer (1) in the thickness direction of the substrate film layer (1).

8. A cover plate, characterized in that: include: Cover plate body (20); The protective film (10) is the protective film (10) according to any one of claims 1 to 7, and the protective film (10) is located on at least one side of the cover plate body (20) in the thickness direction.

9. A method for removing a protective film, characterized in that: Applied to the cover plate (100) according to claim 8, the method comprises: Under preset conditions, a pulling force is applied to a portion of the side edge of the substrate film layer (1) to tear the protective film (10) off the cover plate body (20).

10. The protective film removal method according to claim 9, characterized in that: It also comprises a film-tearing tool, wherein the film-tearing tool is used to apply the preset conditions to the protective film (10), and / or the film-tearing tool is used to apply a tensile force to the substrate film layer (1).

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