Buffer structure, display module and display device

Abstract

The application provides a buffer structure, a display module and a display device. The buffer structure comprises a silicon pressure-sensitive adhesive layer, and the silicon pressure-sensitive adhesive layer is doped with graphene. By doping the silicon pressure-sensitive adhesive layer with graphene, the heat conduction performance of the buffer structure can be effectively improved, the mechanical strength of the buffer structure can be enhanced, the buffer performance of the buffer structure can be improved, and the film printing effect can be improved.

Description

Technical Field

[0001] This application relates to the field of display technology, specifically to a buffer structure, a display module, and a display device. Background Technology

[0002] With the development of display technology, how to balance the buffering performance and film printing performance of the back of the display module has become a key issue in the development of display modules. Summary of the Invention

[0003] In view of this, this application aims to provide a buffer structure, a display module, and a display device that can effectively reduce the thickness of the display panel.

[0004] In a first aspect, this application provides a buffer structure, including:

[0005] Silicon-based pressure-sensitive adhesive layer;

[0006] The silicon-based pressure-sensitive adhesive layer is doped with graphene.

[0007] Optionally, the graphene includes type I graphene and / or type II graphene;

[0008] The first type of graphene includes unmodified graphene;

[0009] The second type of graphene includes modified graphene;

[0010] Optionally, the graphene includes a first type of graphene and a second type of graphene; in the silicon-based pressure-sensitive adhesive layer, the content of the second type of graphene is greater than the content of the first type of graphene.

[0011] Optionally, the content of the first type of graphene includes 4 wt% to 10 wt%;

[0012] Optionally, the content of the first type of graphene is 6 wt%.

[0013] Optionally, the content of the second type of graphene includes 5 wt% to 15 wt%;

[0014] Optionally, the content of the second type of graphene is 11 wt%;

[0015] Optionally, the modified graphene includes a graphene-grafted siloxane structure.

[0016] Optionally, the silicon-based pressure-sensitive adhesive layer includes a first sub-layer and a second sub-layer stacked together;

[0017] Optionally, the graphene content is different in the first sublayer and the second sublayer;

[0018] Optionally, the thicknesses of the first sublayer and the second sublayer are different.

[0019] Optionally, the silicon-based pressure-sensitive adhesive layer further includes a third sub-layer; the third sub-layer is located on the side of the second sub-layer opposite to the first sub-layer;

[0020] Optionally, the graphene content is different in the third sublayer and the second sublayer;

[0021] Optionally, the thickness of the third sublayer and the second sublayer are different;

[0022] Optionally, the thickness of the second sublayer is greater than the thickness of the first sublayer and greater than the thickness of the third sublayer.

[0023] Optionally, the thickness of the first sublayer includes 5 to 40 μm;

[0024] The thickness of the second sublayer ranges from 70 to 140 μm;

[0025] The thickness of the third sublayer ranges from 5 to 40 μm;

[0026] Optionally, the thermal conductivity of the second sublayer is greater than that of the first sublayer and greater than that of the third sublayer.

[0027] Optionally, the first sublayer includes a first silicon-based pressure-sensitive adhesive layer; the second sublayer includes a second silicon-based pressure-sensitive adhesive layer or a thermally conductive layer, wherein the content of silicon-based pressure-sensitive adhesive in the thermally conductive layer is 0; and the third sublayer includes a third silicon-based pressure-sensitive adhesive layer.

[0028] Optionally, the silicone pressure-sensitive adhesive in the first silicone pressure-sensitive adhesive layer, the second silicone pressure-sensitive adhesive layer, and the third silicone pressure-sensitive adhesive layer includes silicone gel;

[0029] Optionally, the silicone gel in the first silicone pressure-sensitive adhesive layer and the third silicone pressure-sensitive adhesive layer is a platinum-catalyzed silicone gel;

[0030] The silicone gel of the second silicone pressure-sensitive adhesive layer is a silicone gel in which hydroxyl groups react with each other;

[0031] Optionally, when the silicon-based pressure-sensitive adhesive layer is doped with a second type of graphene, the content of the second type of graphene doped in the second sublayer includes 12wt% to 15wt%.

[0032] The content of the second type of graphene doped in the first silicon-based pressure-sensitive adhesive layer includes 5 wt% to 11 wt%.

[0033] The content of the second type of graphene doped in the third silicon-based pressure-sensitive adhesive layer includes 5 wt% to 11 wt%.

[0034] Optionally, when the silicon-based pressure-sensitive adhesive layer is doped with type I graphene, the content of type I graphene doped in the second sublayer includes 8wt% to 10wt%.

[0035] The content of the first type of graphene doped in the first silicon-based pressure-sensitive adhesive layer includes 4wt% to 7wt%;

[0036] The content of the first type of graphene doped in the third silicon-based pressure-sensitive adhesive layer includes 4wt% to 7wt%.

[0037] Optionally, the material of the thermally conductive layer includes a modified thermoplastic polyurethane elastomer.

[0038] Optionally, the second sublayer is doped with thermally conductive filler;

[0039] Optionally, the thermally conductive filler includes at least one of boron nitride, aluminum nitride, and silicon carbide;

[0040] Optionally, the thermally conductive filler content in the second sublayer includes 20% to 80%.

[0041] Optionally, the silicon-based pressure-sensitive adhesive layer includes a plurality of receiving holes;

[0042] The graphene is filled in the plurality of accommodating pores.

[0043] Optionally, the silicone pressure-sensitive adhesive in the silicone pressure-sensitive adhesive layer includes silicone gel;

[0044] Optionally, the thickness of the silicon-based pressure-sensitive adhesive layer includes 80–150 μm.

[0045] Secondly, this application provides a buffer structure, including:

[0046] Silicone-based pressure-sensitive adhesive substrate;

[0047] The target dopant is doped into the silicon-based pressure-sensitive adhesive matrix, and the target parameters of the target dopant are higher than the target parameters of the silicon-based pressure-sensitive adhesive matrix; the target parameters include Young's modulus and / or thermal conductivity.

[0048] Optionally, the silicone-based pressure-sensitive adhesive substrate includes a silicone gel substrate;

[0049] Optionally, the target dopant includes graphene;

[0050] Optionally, the graphene includes type I graphene and / or type II graphene;

[0051] The first type of graphene includes unmodified graphene;

[0052] The second type of graphene includes modified graphene;

[0053] Optionally, the graphene includes a first type of graphene and a second type of graphene; in the silicon-based pressure-sensitive adhesive matrix, the content of the second type of graphene is greater than the content of the first type of graphene.

[0054] Optionally, the silicone-based pressure-sensitive adhesive body includes a first body and a second body stacked together;

[0055] The content of the target dopant is different in the first body and the second body.

[0056] Optionally, the silicone-based pressure-sensitive adhesive body further includes a third body; the third body is located on the side of the second body opposite to the first body;

[0057] Optionally, the content of the target dopant is different in the third body and the second body;

[0058] Optionally, the target parameter of the second subject is greater than the target parameter of the first subject and also greater than the target parameter of the third subject.

[0059] Thirdly, this application also provides a display module, including the buffer structure as described in the first aspect of this application;

[0060] Optionally, it also includes a display panel located on one side of the buffer structure;

[0061] Optionally, it also includes a support layer located on the side of the buffer structure opposite to the display panel.

[0062] Fourthly, this application also provides a display device, including the display module as described in the third aspect of this application.

[0063] In this application, the buffer structure includes a silicon-based pressure-sensitive adhesive layer, in which graphene is doped. By doping the silicon-based pressure-sensitive adhesive layer with graphene, the thermal conductivity and mechanical strength of the buffer structure can be effectively improved, thereby enhancing its buffering performance and improving the film printing effect. Attached Figure Description

[0064] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0065] Figure 1This is a schematic diagram of a buffer structure provided in one embodiment of this application;

[0066] Figure 2 This is a schematic diagram of a buffer structure provided in another embodiment of this application;

[0067] Figure 3 This is a schematic diagram of a buffer structure provided in another embodiment of this application;

[0068] Figure 4 This is a schematic diagram of a buffer structure provided in another embodiment of this application;

[0069] Figure 5 This is a schematic diagram of a buffer structure provided in another embodiment of this application;

[0070] Figure 6 This is a schematic diagram of a buffer structure provided in another embodiment of this application;

[0071] Figure 7 This is a schematic diagram of a buffer structure provided in another embodiment of this application;

[0072] Figure 8 This is a schematic diagram of the structure of a display module provided in one embodiment of this application;

[0073] Figure 9 This is a schematic diagram of the structure of a display module provided in another embodiment of this application;

[0074] Figure 10 This is a schematic diagram of the structure of a display device provided in one embodiment of this application. Detailed Implementation

[0075] Unless otherwise defined, the technical or scientific terms used in the embodiments of this specification shall have the ordinary meaning understood by one of ordinary skill in the art to which this specification pertains. The terms "first," "second," and similar terms used in the embodiments of this specification do not indicate any order, quantity, or importance, but are merely used to avoid confusion of constituent elements.

[0076] Unless the context otherwise requires, throughout this specification, "a plurality of" means "at least two," and "including" is interpreted as open-ended or encompassing, that is, "including, but not limited to." In the description of this specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this specification. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example.

[0077] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this specification.

[0078] With the development of display technology, electronic products with large screens, high screen-to-body ratios, curved screens, and foldable screens have become mainstream requirements or configurations. As a result, display modules are developing towards functional integration and ultra-thin and lightweight design. This trend has made the need for buffer protection of display modules increasingly important.

[0079] Currently, the primary method for cushioning and protecting display modules relies on the cushioning structure on the back of the module. This structure mainly uses foam material, but foam generally has limited cushioning performance and is relatively thick, making it difficult to simultaneously improve the cushioning performance of the back of the display module while also achieving weight reduction and thinning. Some cushioning structures on the market use silicone-based pressure-sensitive adhesives instead of foam, which improves the cushioning performance of the back of the display module while also achieving weight reduction and thinning.

[0080] However, the inventors discovered that while the buffer structure of silicone-based pressure-sensitive adhesive materials achieves weight and thinning, it also introduces new problems, such as a significantly increased risk of film printing compared to foam-based buffer structures. Display modules with foam-based buffer structures show good film printing performance in the screen-off state, but the drop height of the ball on the back of the display module is relatively low. In contrast, display modules with silicone-based pressure-sensitive adhesive buffer structures have a higher drop height on the back, resulting in significantly improved buffering performance, but poorer film printing performance in the screen-off state. Therefore, balancing the buffering performance and film printing performance of the display module's back side is a pressing technical problem that needs to be solved.

[0081] Therefore, this application provides a solution that can effectively improve the film printing effect. By doping graphene into the silicon-based pressure-sensitive adhesive layer, the properties of the silicon-based pressure-sensitive adhesive layer can be improved by the doped graphene. This results in a significant improvement in the thermal conductivity and mechanical strength of the graphene-doped silicon-based pressure-sensitive adhesive layer, thereby improving the buffering performance of the buffer structure and improving the film printing effect.

[0082] Specifically, as an optional implementation of the content disclosed in this application, the embodiments of this application provide a buffer structure. Figure 1 This is a schematic diagram of a buffer structure provided in one embodiment of this application, as shown below. Figure 1 As shown, the buffer structure may include at least: a silicon-based pressure-sensitive adhesive layer 10; the silicon-based pressure-sensitive adhesive layer 10 is doped with graphene.

[0083] It should be noted that graphene is one of the strongest known materials, while also possessing excellent toughness and flexibility. Graphene's theoretical Young's modulus reaches 1.0 TPa, and its inherent tensile strength is 130 GPa. Reduced graphene modified with hydrogen plasma also exhibits very good strength, with an average modulus reaching 0.25 TPa. Furthermore, graphene possesses excellent thermal conductivity. Pure, defect-free monolayer graphene has a thermal conductivity as high as 5300 W / mK, making it the carbon material with the highest thermal conductivity to date, exceeding that of single-walled carbon nanotubes (3500 W / mK) and multi-walled carbon nanotubes (3000 W / mK).

[0084] In application, the silicone pressure-sensitive adhesive layer is mainly composed of silicone pressure-sensitive adhesive, and silicone gel can be selected as the silicone pressure-sensitive adhesive.

[0085] Doping graphene into the silicon-based pressure-sensitive adhesive layer 10, that is, doping graphene into the silicon gel system, can improve the thermal conductivity and mechanical strength of the silicon gel system, thereby helping to improve the film printing effect.

[0086] Graphene may include type I graphene and / or type II graphene. Type I graphene may include unmodified graphene; type II graphene may include modified graphene.

[0087] Unmodified graphene can refer to pure graphene.

[0088] In practice, graphene can be type I graphene, type II graphene, or a combination of both.

[0089] Specifically, the silicon-based pressure-sensitive adhesive layer 10 may be doped with only type I graphene, and the content of type I graphene may include 4 wt% to 10 wt%. For example, the content of type I graphene may be 4 wt%, 5 wt%, 8 wt%, or 10 wt%.

[0090] When type I graphene is doped into the silicon-based pressure-sensitive adhesive layer 10, the Young's modulus and thermal conductivity of the layer increase with the increase of type I graphene content. Simultaneously, the adhesion decreases, the buffer absorption rate remains relatively unchanged, and the film printing effect is significantly improved. However, when the type I graphene content in the silicon-based pressure-sensitive adhesive layer exceeds 10 wt%, uneven dispersion occurs. Therefore, when doping the silicon-based pressure-sensitive adhesive layer 10 with type I graphene, maintaining the type I graphene content between 4 wt% and 10 wt% can improve the thermal conductivity and buffering performance of the buffer structure, thereby improving the film printing effect, while also avoiding the problem of uneven dispersion.

[0091] Among them, the buffer absorption rate refers to the lowest height value at which no bright spots appear when a ball is dropped onto the back of the display module after the buffer structure is applied to the display module.

[0092] Preferably, the content of the first type of graphene in the silicon-based pressure-sensitive adhesive layer 10 is 6 wt%.

[0093] In practical applications, the silicon-based pressure-sensitive adhesive layer 10 can also be doped with only type II graphene.

[0094] Specifically, the content of type II graphene in the silicon-based pressure-sensitive adhesive layer 10 can range from 5 wt% to 15 wt%. For example, the content of type II graphene can be 5 wt%, 8 wt%, 10 wt%, 12%, or 15 wt%.

[0095] When doping the silicon-based pressure-sensitive adhesive layer 10 with type II graphene, the Young's modulus and thermal conductivity of the silicon-based pressure-sensitive adhesive layer 10 increase with the increase of type II graphene content. Simultaneously, the adhesion decreases, the back-side cushioning performance remains largely unchanged, and the film printing effect is significantly improved. Therefore, when doping the silicon-based pressure-sensitive adhesive layer 10 with type II graphene, maintaining the type II graphene content between 5wt% and 15wt% allows the buffer structure to possess good thermal conductivity and cushioning performance while maintaining sufficient adhesion.

[0096] Preferably, the content of type II graphene in the silicon-based pressure-sensitive adhesive layer 10 is 11 wt%.

[0097] To further verify that silicon-based pressure-sensitive adhesive layers doped with graphene and silicon-based pressure-sensitive adhesive layers doped with modified graphene have good thermal conductivity, buffering performance, and film printing effect, the performance of conventional foam materials, conventional silicone gel materials, silicone gel materials doped with 5 wt% graphene, and silicone gel materials doped with 11 wt% modified graphene was compared below, as shown in Table 1.

[0098] Table 1 Performance Comparison Results

[0099]

[0100]

[0101] The film printing effect is the minimum pressure value required to prevent film printing defects when pressing the back of the display module with a φ3mm pressure head. The higher the pressure value, the higher the resistance to film printing.

[0102] As shown in Table 1, the thermal conductivity and Young's modulus of the silicon gel doped with 5 wt% type I graphene and the silicon gel doped with 11 wt% type II graphene were significantly improved. The adhesion was slightly weakened, but the change was minor, and the buffer absorption rate remained almost unchanged. In terms of film printing performance, the silicon gel doped with type I graphene (unmodified graphene) and the silicon gel doped with type II graphene (modified graphene) showed a more significant improvement compared to the undoped silicon gel. Therefore, doping silicon-based pressure-sensitive adhesive layers with type I or type II graphene can effectively improve the thermal conductivity and mechanical strength of the buffer structure, thereby enhancing the buffering performance and further improving the film printing effect, thus balancing both buffering and film printing performance.

[0103] Of course, this application is not limited to this. In some embodiments, the silicon-based pressure-sensitive adhesive layer 10 in the buffer structure may also be doped with both type I graphene and type II graphene.

[0104] The content of type I graphene can be maintained at 4wt% to 10wt%, and the content of type II graphene can be maintained at 5wt% to 15wt%. Simultaneous doping of type I and type II graphene in the silicon-based pressure-sensitive adhesive layer 10 can further improve the buffering performance and thermal conductivity of the buffer structure, and improve the film printing effect.

[0105] To further enhance the buffering capacity and thermal conductivity of the buffer structure, the content of type II graphene in the silicon-based pressure-sensitive adhesive layer can be greater than the content of type I graphene.

[0106] Preferably, the content of the first type of graphene is 6 wt% and the content of the second type of graphene is 11 wt%.

[0107] In some embodiments, the modified graphene may include a graphene-grafted siloxane structure.

[0108] Specifically, modified graphene can be obtained by oxidative grafting modification of pure graphene.

[0109] In practice, pure graphene can first be reacted with oxygen to graft polar groups such as -COOH onto the end groups of the graphene, and then KH550 silane coupling agent can be added to graft silane groups onto the graphene to obtain modified graphene.

[0110] After obtaining modified graphene, it can be added to the silicon-based pressure-sensitive adhesive reaction system. The modified graphene is grafted onto the side chains of the silicon-based pressure-sensitive adhesive to obtain a silicon-based pressure-sensitive adhesive layer. In this way, a silicon-based pressure-sensitive adhesive layer doped with modified graphene is obtained, which has significantly improved thermal conductivity and buffering performance.

[0111] In some embodiments, such as Figure 2As shown, the silicon-based pressure-sensitive adhesive layer 10 may include a first sublayer 101 and a second sublayer 102 stacked together.

[0112] The graphene content differs between the first sublayer 101 and the second sublayer 102.

[0113] For example, the content of type I graphene in the first sublayer 101 can be 8 wt%, and the content of type I graphene in the second sublayer 102 can be 9 wt%. Alternatively, the content of type II graphene in the first sublayer 101 can be 11 wt%, and the content of type II graphene in the second sublayer 102 can be 13 wt%.

[0114] By setting different graphene contents in the first sublayer 101 and the second sublayer 102, the two sides of the silicon-based pressure-sensitive adhesive layer 10 can have different adhesion forces. This allows for maximizing the buffering performance and mechanical strength of the buffer structure while meeting the different adhesion force requirements on different sides. Furthermore, it saves on the amount of graphene used, reducing the manufacturing cost of the buffer structure.

[0115] Of course, this application's specification is only an example of the different graphene content in the first sublayer 101 and the second sublayer 102, but this application is not limited to this. In some other embodiments, the graphene content in the first sublayer 101 and the second sublayer 102 can also be the same.

[0116] In some embodiments, the first sublayer 101 and the second sublayer 102 may have the same or different film thicknesses.

[0117] When the film thicknesses of the first sublayer 101 and the second sublayer 102 are different, the film thicknesses of the two sublayers can be adjusted according to their different properties. For example, if the mechanical strength of the first sublayer 101 is higher than that of the second sublayer 102, the film thickness of the first sublayer 101 can be set to be greater than that of the second sublayer 102, thereby improving the overall mechanical strength of the buffer structure.

[0118] In some embodiments, such as Figure 3 As shown, the silicon-based pressure-sensitive adhesive layer 10 may further include a third sublayer 103. The third sublayer 103 is located on the side of the second sublayer 102 opposite to the first sublayer 101.

[0119] In practice, the graphene content in the third sublayer and the second sublayer can be different.

[0120] For example, the content of type I graphene in the second sublayer 102 can be 9 wt%, and the content of type I graphene in the third sublayer 103 can be 8 wt%. Alternatively, the content of type II graphene in the second sublayer 102 can be 11 wt%, and the content of type II graphene in the third sublayer 103 can be 14 wt%.

[0121] By setting different graphene contents in the second sublayer 102 and the third sublayer 103, the properties of the buffer structure can be easily adjusted. For example, the two sides of the buffer structure need to maintain a certain degree of adhesion. Therefore, the first sublayer 101 and the third sublayer 103 need to have a certain degree of adhesion. However, the second sublayer 102, as the intermediate layer, does not have a strict requirement for a certain degree of adhesion. Therefore, the mechanical strength or thermal conductivity of the buffer structure can be improved by increasing the mechanical strength or thermal conductivity of the second sublayer 102, without having to consider the adhesion of the second sublayer 102.

[0122] Of course, the description of this application is only used as an example of different graphene contents in the first and second sublayers, and / or different graphene contents in the second and third sublayers. However, this application is not limited to this. In some other embodiments, the graphene contents in the first and second sublayers can be the same, and / or the graphene contents in the second and third sublayers can be the same.

[0123] In some embodiments, the film thicknesses of the third sublayer and the second sublayer may be different.

[0124] Specifically, the film thickness of the two sublayers can be adjusted according to the different performance requirements of the third and second sublayers.

[0125] In practice, the thickness of the second sublayer can be greater than that of the first sublayer and also greater than that of the third sublayer.

[0126] Since the second sublayer is located in the middle film layer of the buffer structure, its buffering performance and adhesion can be significantly different from those of the first and third sublayers.

[0127] For example, if the buffering performance of a buffer structure needs to be adjusted using a second sublayer, its thickness can be increased while simultaneously improving its mechanical strength, making it greater than that of the first and third sublayers. This significantly enhances the buffering performance of the structure. The first and third sublayers only require strong adhesion; their thicknesses are not necessary.

[0128] In practice, the thickness of the first sublayer can be set in the range of 5 to 40 μm; the thickness of the second sublayer can be set in the range of 70 to 140 μm; and the thickness of the third sublayer can be set in the range of 5 to 40 μm.

[0129] For example, such as Figure 4 As shown, the thickness h1 of the first sub-layer 101 and the thickness h3 of the third sub-layer 103 can both be set to 5 μm, and the thickness h2 of the second sub-layer 102 can be set to 140 μm. The first sub-layer 101, the second sub-layer 102, and the third sub-layer 103 are stacked sequentially. The buffer structure is a three-layer silicon-based pressure-sensitive adhesive layer structure with a thickness of 150 μm. This avoids both the buffer structure being too thick, which would hinder the thinning of the display module, and the buffer structure being too thin, which would result in insufficient buffering performance. The sequential stacking of the first sub-layer 101, the second sub-layer 102, and the third sub-layer 103 allows the buffer structure to have the same adhesion as the first sub-layer 101 and the third sub-layer 103, while also possessing the same thermal conductivity and buffering performance as the second sub-layer 102.

[0130] In this way, by maintaining a large thickness in the second sub-layer 102, which is greater than the thickness of the first sub-layer 101 and also greater than the thickness of the third sub-layer 103, the buffer structure can have both strong adhesion and high thermal conductivity and buffering performance.

[0131] In addition, the thermal conductivity of the second sublayer of the buffer structure can be set to be greater than that of the first sublayer and greater than that of the third sublayer.

[0132] When the thickness of the second sublayer is greater than that of the other sublayers, the greater the thermal conductivity of the second sublayer located in the middle layer of the buffer structure, the better the thermal conductivity of the buffer structure. Setting the thermal conductivity of the second sublayer of the buffer structure to be greater than that of the first sublayer and greater than that of the third sublayer effectively improves the thermal conductivity of the buffer structure.

[0133] In some embodiments, the first sublayer may include a first silicon-based pressure-sensitive adhesive layer; the second sublayer may include a second silicon-based pressure-sensitive adhesive layer or a thermally conductive layer; and the third sublayer may include a third silicon-based pressure-sensitive adhesive layer.

[0134] When the second sublayer is a thermally conductive layer, the content of silicon-based pressure-sensitive adhesive in the thermally conductive layer is 0.

[0135] In other words, the main adhesive layers of the first, second, and third sublayers can all be silicone-based pressure-sensitive adhesives; or, the main materials of the first and third sublayers can be silicone-based pressure-sensitive adhesives, while the main material of the second sublayer is not a silicone-based pressure-sensitive adhesive.

[0136] In practice, the silicone pressure-sensitive adhesive in the first, second, and third silicone pressure-sensitive adhesive layers may include silicone gel.

[0137] The silicone gel in the first and third silicone pressure-sensitive adhesive layers can be platinum-catalyzed silicone gels; the silicone gel in the second silicone pressure-sensitive adhesive layer can be a silicone gel that reacts with hydroxyl groups.

[0138] Specifically, the silicone gels in the first and third silicone-based pressure-sensitive adhesive layers are platinum-catalyzed silicone gels. These silicone gels have an adhesive surface, which allows them to adhere the copper foil (support layer) and the screen (display panel). The silicone gel in the second silicone-based pressure-sensitive adhesive layer is a silicone gel formed by the interaction of hydroxyl groups. It is not adhesive itself but has excellent cushioning properties and a high Young's modulus, resulting in better film printing. Thus, the three-layer silicone gel structure can balance excellent back-side drop ball performance and excellent film printing effect, thereby further improving the cushioning performance of the buffer structure and enhancing the film printing effect.

[0139] In some embodiments, to further enhance the buffering performance of the buffer structure and improve the effect of film printing, when the silicon-based pressure-sensitive adhesive layer is doped with a second type of graphene, the content of the second type of graphene doped in the second sublayer (the second silicon-based pressure-sensitive adhesive layer or the thermally conductive layer) may include 12wt% to 15wt%; the content of the second type of graphene doped in the first silicon-based pressure-sensitive adhesive layer may include 5wt% to 11wt%; and the content of the second type of graphene doped in the third silicon-based pressure-sensitive adhesive layer may include 5wt% to 11wt%.

[0140] The second sublayer (the second silicon-based pressure-sensitive adhesive layer or thermally conductive layer) is located between the first and third silicon-based pressure-sensitive adhesive layers. Its adhesion requirements are not high. Controlling the content of type II graphene in the second sublayer to 12wt%–15wt% ensures that the second sublayer possesses high thermal conductivity and a strong Young's modulus, thereby improving the overall thermal conductivity and Young's modulus of the buffer structure. The first and third silicon-based pressure-sensitive adhesive layers, located on either side of the second sublayer, need to possess a certain degree of adhesion to adhere to the copper foil and the screen. Therefore, controlling the content of type II graphene in the first silicon-based pressure-sensitive adhesive layer to 5wt%–11wt% and in the third silicon-based pressure-sensitive adhesive layer to 5wt%–11wt% ensures both sufficient adhesion and high thermal conductivity and buffering performance of the buffer structure.

[0141] In implementation, the first and third silicone-based pressure-sensitive adhesive layers can be made of the same material, ensuring that they maintain identical properties. This guarantees that both sides of the buffer structure possess the same adhesion, thermal conductivity, and cushioning performance.

[0142] Similarly, when the silicon-based pressure-sensitive adhesive layer is doped with type I graphene, the content of type I graphene doped in the second sublayer (second silicon-based pressure-sensitive adhesive layer or thermally conductive layer) can be 8 wt% to 10 wt%; the content of type I graphene doped in the first silicon-based pressure-sensitive adhesive layer can be 4 wt% to 7 wt%; and the content of type I graphene doped in the third silicon-based pressure-sensitive adhesive layer 103 can be 4 wt% to 7 wt%.

[0143] In silicon-based pressure-sensitive adhesive layers, when the content of doped type I graphene is 8wt%–10wt%, compared to when the content of doped type I graphene is 4wt%–7wt%, the adhesion is lower, but the thermal conductivity, Young's modulus, and film printing effect are all improved. Therefore, by controlling the content of type I graphene in the second sublayer to 8wt%–10wt%, the content of doped type I graphene in the first silicon-based pressure-sensitive adhesive layer to 4wt%–7wt%, and the content of doped type I graphene in the third silicon-based pressure-sensitive adhesive layer to 4wt%–7wt%, it is possible to ensure that the buffer structure has a certain degree of adhesion while also ensuring its high thermal conductivity and buffering performance.

[0144] In some embodiments, the second sublayer (the second silicon-based pressure-sensitive adhesive layer or thermally conductive layer) may also be doped with thermally conductive fillers.

[0145] Specifically, the second sublayer can be doped with only thermally conductive fillers, without graphene.

[0146] The thermally conductive filler may include at least one of boron nitride (BN), aluminum nitride (ALN), and silicon carbide (SiC).

[0147] Boron nitride possesses resistance to chemical corrosion and has a thermal conductivity between 20 and 200 W / mK, exhibiting excellent thermal conductivity. Its hardness is second only to diamond, making it a superhard material. Using boron nitride as a thermally conductive filler ensures that the second sublayer has good thermal conductivity and strong mechanical strength, thereby guaranteeing the buffer structure has both excellent thermal conductivity and cushioning properties.

[0148] Aluminum nitride, as a solid nitride of aluminum, has a thermal conductivity between 20 and 321 W / mK, exhibiting excellent thermal conductivity. Furthermore, its Mohs hardness is between 9 and 10, making it a very hard material. Using aluminum nitride as a thermally conductive filler ensures that the second sublayer possesses good thermal conductivity and strong mechanical strength, thereby guaranteeing the buffer structure has both excellent thermal conductivity and cushioning properties.

[0149] Silicon carbide has a thermal conductivity between 120 and 200 W / mK and a Mohs hardness of 9.2 to 9.3. It has good thermal conductivity and strong hardness, making it one of the preferred materials for thermally conductive fillers. It can also ensure that the second sublayer has good thermal conductivity and strong mechanical strength, thereby ensuring that the buffer structure has good thermal conductivity and buffering properties.

[0150] When thermally conductive fillers are doped into the second sublayer (the second silicon-based pressure-sensitive adhesive layer or thermally conductive layer), the content of thermally conductive fillers in the second sublayer can include 20% to 80%.

[0151] For example, 60% boron nitride can be doped into the second sublayer, which can improve the thermal conductivity of the buffer structure; another example is that 80% aluminum nitride can be doped into the second sublayer; yet another example is that 50% silicon carbide can be doped into the second sublayer, and so on.

[0152] It should be noted that the specification section of this application is only used as an example of doping only thermally conductive filler in the second sublayer, but this application is not limited to this. In some other embodiments, graphene can also be doped in the second sublayer doped with thermally conductive filler. The content and composition of the doped graphene can refer to the graphene described in any of the above embodiments, and will not be repeated here.

[0153] In some embodiments, the material of the thermally conductive layer may include a modified thermoplastic polyurethane elastomer.

[0154] Modified thermoplastic polyurethane elastomers possess excellent comprehensive properties, including high strength, high toughness, wear resistance, and strong thermal conductivity. Using modified thermoplastic polyurethane elastomers as the material for the thermally conductive layer, and doping it with the aforementioned thermally conductive fillers and / or graphene, ensures that the thermally conductive layer has good thermal conductivity and strong mechanical strength, thereby ensuring that the buffer structure has good thermal conductivity and buffering properties.

[0155] Of course, the description in this application only uses modified thermoplastic polyurethane elastomer as an example of the material of the thermal conductive layer, but this application is not limited to this. In some other embodiments, the material of the thermal conductive layer can also be other materials with excellent thermal conductivity and high hardness, which will not be listed here.

[0156] In some embodiments, such as Figure 5 As shown, the silicon-based pressure-sensitive adhesive layer 10 may include multiple accommodating holes K; graphene is filled in the multiple accommodating holes K.

[0157] In practice, multiple receiving holes K can be evenly distributed on the silicon-based pressure-sensitive adhesive layer 10. The receiving holes K can penetrate the silicon-based pressure-sensitive adhesive layer 10, and graphene is uniformly filled in the receiving holes K.

[0158] Because graphene (either type I or type II graphene) has strong thermal conductivity and mechanical strength, filling the containment holes K with graphene can effectively enhance the thermal conductivity and mechanical strength of the buffer structure.

[0159] In application, the cross-sectional shape of the receiving hole K can be circular, but this application is not limited to this. In some other embodiments, the cross-sectional shape of the receiving hole K can also be other shapes, such as... Figure 6 As shown, the cross-sectional shape of the accommodating hole K can be rectangular, or as shown in the figure. Figure 7 As shown, the cross-sectional shape of the receiving hole K is triangular, etc. The specific shape can be set according to actual needs, and no specific limitation is made here.

[0160] In some embodiments, the thickness of the silicon-based pressure-sensitive adhesive layer 10 may include 80–150 μm.

[0161] By controlling the thickness of the silicon-based pressure-sensitive adhesive layer 10 to be between 80 and 150 μm, it is possible to ensure that the silicon-based pressure-sensitive adhesive layer 10 has a certain thickness, thereby enabling the buffer structure to have sufficient mechanical strength and buffering performance, while avoiding excessive thickness that would burden the thinning of the display module.

[0162] As another optional implementation of the disclosure of this application, embodiments of this application also provide a buffer structure, which may include: a silicon-based pressure-sensitive adhesive body; a target dopant, wherein the target dopant is doped into the silicon-based pressure-sensitive adhesive body, and the target parameters of the target dopant are higher than the target parameters of the silicon-based pressure-sensitive adhesive body; the target parameters include Young's modulus and / or thermal conductivity.

[0163] In this embodiment, a target dopant with a target parameter higher than that of the silicon-based pressure-sensitive adhesive is incorporated into the silicon-based pressure-sensitive adhesive, thereby enhancing the target parameter of the buffer structure and resulting in a significant improvement in the Young's modulus and / or thermal conductivity of the buffer structure.

[0164] Specifically, the silicone-based pressure-sensitive adhesive substrate may include a silicone gel substrate.

[0165] By using silica gel as the main material of the buffer structure and doping it with target dopants, the thermal conductivity and Young's modulus of the silica gel body are improved on the basis of the silica gel properties, so that the buffer structure can have good thermal conductivity, buffering performance and film printing effect.

[0166] The target dopant may include graphene.

[0167] By doping graphene into the silicon-based pressure-sensitive adhesive matrix, the properties of the silicon-based pressure-sensitive adhesive matrix can be improved by the doped graphene. The silicon-based pressure-sensitive adhesive matrix with graphene doping has a significant improvement in thermal conductivity and mechanical strength, thereby improving the buffering performance of the buffer structure and improving the film printing effect.

[0168] Graphene may include type I graphene and / or type II graphene. Type I graphene may include unmodified graphene; type II graphene may include modified graphene.

[0169] Unmodified graphene can refer to pure graphene.

[0170] In practice, graphene can be type I graphene, type II graphene, or a combination of both.

[0171] Specifically, the silicon-based pressure-sensitive adhesive matrix may contain only type I graphene, and the content of type I graphene may range from 4 wt% to 10 wt%. For example, the content of type I graphene may be 4 wt%, 5 wt%, 8 wt%, or 10 wt%.

[0172] When type I graphene is doped into a silicon-based pressure-sensitive adhesive matrix, the Young's modulus and thermal conductivity of the matrix increase with the increase of type I graphene content. Simultaneously, adhesion decreases, back-side cushioning performance remains largely unchanged, and the film printing effect is significantly improved. However, when the type I graphene content in the silicon-based pressure-sensitive adhesive matrix exceeds 10 wt%, uneven dispersion occurs. Therefore, when doping the silicon-based pressure-sensitive adhesive matrix with type I graphene, maintaining the type I graphene content between 4 wt% and 10 wt% can improve the thermal conductivity and cushioning performance of the buffer structure, thereby improving the film printing effect, while also avoiding the problem of uneven dispersion.

[0173] Preferably, the content of type I graphene in the silicon-based pressure-sensitive adhesive matrix is ​​6 wt%.

[0174] In practical applications, the silicon-based pressure-sensitive adhesive matrix can also be doped with only type II graphene.

[0175] Specifically, the content of type II graphene in the silicon-based pressure-sensitive adhesive matrix can range from 5 wt% to 15 wt%. For example, the content of type II graphene can be 5 wt%, 8 wt%, 10 wt%, 12%, or 15 wt%.

[0176] When doping silicon-based pressure-sensitive adhesives with type II graphene, the Young's modulus and thermal conductivity of the adhesive matrix increase with increasing type II graphene content. Simultaneously, adhesion decreases, back-side cushioning performance remains largely unchanged, and the film printing effect shows a significant improvement. Therefore, maintaining a type II graphene content of 5wt%–15wt% in silicon-based pressure-sensitive adhesives allows the cushioning structure to possess good thermal conductivity and cushioning performance while maintaining sufficient adhesion.

[0177] Preferably, the content of type II graphene in the silicon-based pressure-sensitive adhesive matrix is ​​11 wt%.

[0178] Of course, this application is not limited to this. In some embodiments, the buffer structure may also contain both type I graphene and type II graphene in the silicon-based pressure-sensitive adhesive body.

[0179] The content of type I graphene can be maintained at 4wt% to 10wt%, and the content of type II graphene can be maintained at 5wt% to 15wt%. Simultaneous doping of type I and type II graphene into the silicon-based pressure-sensitive adhesive matrix can further improve the buffering performance and thermal conductivity of the buffer structure, and improve the film printing effect.

[0180] To further enhance the buffering capacity and thermal conductivity of the buffer structure, the content of type II graphene in the silicon-based pressure-sensitive adhesive matrix can be greater than the content of type I graphene.

[0181] Preferably, the content of the first type of graphene is 6 wt% and the content of the second type of graphene is 11 wt%.

[0182] In some embodiments, the modified graphene may include a graphene-grafted siloxane structure.

[0183] In practice, unmodified graphene can first be reacted with oxygen to graft polar groups such as -COOH onto the end groups of the unmodified graphene. Then, KH550 silane coupling agent can be added to graft silane groups onto the graphene to obtain modified graphene.

[0184] After obtaining modified graphene, it can be added to the silica gel reaction system, where it is grafted onto the silica gel side chains to obtain a buffer structure. This results in a silica-based pressure-sensitive adhesive matrix doped with modified graphene, exhibiting significantly improved thermal conductivity and buffering performance.

[0185] In some embodiments, the silicon-based pressure-sensitive adhesive substrate may include a first substrate and a second substrate stacked together; the content of the target dopant is different in the first substrate and the second substrate.

[0186] For example, the content of type I graphene in the first substrate can be 8 wt%, and the content of type I graphene in the second substrate can be 9 wt%. As another example, the content of type II graphene in the first substrate can be 11 wt%, and the content of type II graphene in the second substrate can be 13 wt%.

[0187] By setting different amounts of the target dopant in the first and second substrates, the two sides of the silicon-based pressure-sensitive adhesive substrate can have different adhesion forces. This allows for maximizing the buffering performance and mechanical strength of the buffer structure while meeting the different adhesion force requirements on different sides. Furthermore, it can reduce the amount of target dopant used, thus lowering the fabrication cost of the buffer structure.

[0188] In some embodiments, the silicone pressure-sensitive adhesive body may further include a third body; the third body is located on the side of the second body opposite to the first body.

[0189] During implementation, the content of the target dopant differs between the third and second subjects.

[0190] For example, the content of type I graphene in the second substrate can be 9 wt%, and the content of type I graphene in the third substrate can be 8 wt%. Alternatively, the content of type II graphene in the second substrate can be 11 wt%, and the content of type II graphene in the third substrate can be 14 wt%.

[0191] By setting different amounts of the target dopant in the second and third substrates, the characteristics of the buffer structure can be easily adjusted. For example, the two sides of the buffer structure need to maintain a certain adhesion force. Therefore, the first and third substrates need to have a certain adhesion force. However, the second substrate, as the intermediate layer, does not have a strict requirement for a certain adhesion force. Therefore, the mechanical strength or thermal conductivity of the buffer structure can be improved by increasing the mechanical strength or thermal conductivity of the second substrate, without having to consider the adhesion force of the second substrate.

[0192] Of course, the description of this application is only used as an example to illustrate that the content of the target dopant in the first body and the second body is different, and / or the content of the target dopant in the second body and the third body is different. However, this application is not limited to this. In some other embodiments, the content of the target dopant in the first body and the second body can be the same, and / or the content of the target dopant in the second body and the third body can be the same.

[0193] In some embodiments, the target parameter of the second subject can be greater than the target parameter of the first subject and greater than the target parameter of the third subject, thereby improving the characteristics of the buffer structure in terms of the target parameter.

[0194] For example, if the target parameter is thermal conductivity, then the thermal conductivity of the second body is greater than that of the first body, and also greater than that of the third body. The second body is the body located between the first and third bodies in the buffer structure; therefore, there is no need to consider the adhesive force of the second body, and its thermal conductivity can be directly increased, thereby effectively improving the overall thermal conductivity of the buffer structure.

[0195] As another optional implementation of the disclosure of this application, embodiments of this application also provide a display module, including the buffer structure as described in any of the above embodiments.

[0196] In some embodiments, the display module may also include a display panel located on one side of the buffer structure.

[0197] When implementing, such as Figure 8 As shown, the buffer structure S can be located on the back of the display panel P (the side of the substrate of the display panel P away from the light-emitting side) to provide buffer protection.

[0198] In some embodiments, such as Figure 9 As shown, the display module may also include a support layer Z, which is located on the side of the buffer structure S opposite to the display panel P.

[0199] In application, the support layer Z can be a film layer made of copper foil.

[0200] As an optional implementation of the disclosure in this application, an embodiment of this application also provides a display device, which includes: a display module as provided in any of the above embodiments. Figure 10 As shown, Figure 10 This is a schematic diagram of the structure of a display device provided in one embodiment of this application. The display device can be a smartphone, a tablet computer, or a digital camera, etc., which will not be described in detail here.

[0201] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0202] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A buffer structure, characterized in that, include: A silicon-based pressure-sensitive adhesive layer includes multiple accommodating holes; the silicon-based pressure-sensitive adhesive layer includes a first sublayer, a second sublayer, and a third sublayer stacked together, the third sublayer being located on the side of the second sublayer facing away from the first sublayer; the first sublayer includes a first silicon-based pressure-sensitive adhesive layer; the second sublayer includes a second silicon-based pressure-sensitive adhesive layer; the third sublayer includes a third silicon-based pressure-sensitive adhesive layer; the silicon-based pressure-sensitive adhesive in the first, second, and third silicon-based pressure-sensitive adhesive layers includes silicone gel; the silicone gel in the first and third silicon-based pressure-sensitive adhesive layers is platinum-catalyzed silicone gel; the silicone gel in the second silicon-based pressure-sensitive adhesive layer is a silicone gel that reacts with hydroxyl groups; the second sublayer is doped with thermally conductive filler. The silicon-based pressure-sensitive adhesive layer is doped with graphene, which fills the plurality of accommodating pores; The graphene includes type I graphene and type II graphene; in the silicon-based pressure-sensitive adhesive layer, the content of type II graphene is greater than the content of type I graphene. The first type of graphene includes unmodified graphene; the second type of graphene includes modified graphene. The content of the first type of graphene ranges from 4 wt% to 10 wt%; the content of the second type of graphene ranges from 5 wt% to 15 wt%. The graphene content differs between the first sublayer and the second sublayer; the graphene content also differs between the third sublayer and the second sublayer.

2. The buffer structure according to claim 1, characterized in that, The content of the first type of graphene is 6 wt%.

3. The buffer structure according to claim 1, characterized in that, The content of the second type of graphene is 11 wt%.

4. The buffer structure according to claim 1, characterized in that, The modified graphene includes a graphene-grafted siloxane structure.

5. The buffer structure according to claim 1, characterized in that, The thicknesses of the first sublayer and the second sublayer are different.

6. The buffer structure according to claim 5, characterized in that, The third sublayer and the second sublayer have different film thicknesses.

7. The buffer structure according to claim 1, characterized in that, The thickness of the second sublayer is greater than that of the first sublayer and greater than that of the third sublayer.

8. The buffer structure according to claim 1, characterized in that, The thickness of the first sublayer ranges from 5 to 40 μm; The thickness of the second sublayer ranges from 70 to 140 μm; The thickness of the third sublayer ranges from 5 to 40 μm.

9. The buffer structure according to claim 1, characterized in that, The thermal conductivity of the second sublayer is greater than that of the first sublayer, and also greater than that of the third sublayer.

10. The buffer structure according to claim 1, characterized in that, When the silicon-based pressure-sensitive adhesive layer is doped with type II graphene, the content of type II graphene doped in the second sublayer includes 12wt%~15wt%; The content of the second type of graphene doped in the first silicon-based pressure-sensitive adhesive layer ranges from 5 wt% to 11 wt%. The content of the second type of graphene doped in the third silicon-based pressure-sensitive adhesive layer is 5wt% to 11wt%.

11. The buffer structure according to claim 1, characterized in that, When the silicon-based pressure-sensitive adhesive layer is doped with type I graphene, the content of type I graphene doped in the second sublayer includes 8wt%~10wt%; The content of the first type of graphene doped in the first silicon-based pressure-sensitive adhesive layer is 4wt%~7wt%; The content of the first type of graphene doped in the third silicon-based pressure-sensitive adhesive layer is 4wt% to 7wt%.

12. The buffer structure according to claim 1, characterized in that, The thermally conductive filler includes at least one of boron nitride, aluminum nitride, and silicon carbide.

13. The buffer structure according to claim 1, characterized in that, The thermally conductive filler content in the second sublayer ranges from 20% to 80%.

14. The buffer structure according to claim 1, characterized in that, The silicone-based pressure-sensitive adhesive layer includes silicone gel.

15. The buffer structure according to claim 1, characterized in that, The thickness of the silicon-based pressure-sensitive adhesive layer ranges from 80 to 150 μm.

16. A display module, characterized in that, Includes the buffer structure as described in any one of claims 1 to 15.

17. The display module according to claim 16, characterized in that, It also includes a display panel located on one side of the buffer structure.

18. The display module according to claim 17, characterized in that, It also includes a support layer located on the side of the buffer structure opposite to the display panel.

19. A display device, characterized in that, Includes the display module as described in any one of claims 16 to 18.

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