Silicone pressure-sensitive adhesive, cushion structure, display module and display device

Abstract

The present application relates to the technical field of display module, and in particular to a silicon pressure-sensitive adhesive, a buffer structure, a display module and a display device. The provided silicon pressure-sensitive adhesive comprises modified silicone rubber, and the modified silicone rubber comprises polymer grafted methyl vinyl silicone rubber, wherein the polymer comprises a polymer with oxygen-containing groups and aromatic groups; in the polymer grafted methyl vinyl silicone rubber, the content of the polymer is 1-10 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber. A buffer structure comprises the provided silicon pressure-sensitive adhesive. The present application can improve the damping performance of the silicon pressure-sensitive adhesive, and further improve the back impact resistance of the buffer structure and the display module using the silicon pressure-sensitive adhesive, and improve the film printing resistance of the display module.

Description

Technical Field

[0001] This invention relates to the field of display module technology, and more specifically, to a silicon-based pressure-sensitive adhesive, a buffer structure, a display module, and a display device. Background Technology

[0002] With the development of the display industry, electronic products such as mobile phones are increasingly susceptible to damage from mechanical vibration, making the need for buffer protection of display modules increasingly important. The application of silicone-based pressure-sensitive adhesives, such as silicone gel damping materials, can effectively reduce display defects caused by vibration and extend the lifespan of equipment.

[0003] In related technologies, commonly used damping silicone materials exhibit a rapid decrease in damping loss factor as the resonant intensity increases with rising ambient temperature. This makes them unsuitable for the demanding operating conditions of high-precision fields such as mobile phones and other electronic products, which require a wide frequency range and experience alternating high and low temperatures. Therefore, expanding the operating temperature and frequency range of silicone damping materials is crucial. In other words, improving the damping performance of silicone-based pressure-sensitive adhesives has become an urgent technical problem to be solved. Summary of the Invention

[0004] In view of this, the present invention aims to at least partially solve one of the technical problems in the related art. To this end, the present invention provides a silicon-based pressure-sensitive adhesive, a buffer structure, a display module, and a display device, which can improve the damping performance of the silicon-based pressure-sensitive adhesive, thereby improving the back-side impact resistance, anti-film printing level, and other properties of the buffer structure and display module using the silicon-based pressure-sensitive adhesive.

[0005] To solve the above-mentioned technical problems, this application is implemented as follows:

[0006] According to one aspect of this application, this application provides a silicone-based pressure-sensitive adhesive, said silicone-based pressure-sensitive adhesive comprising modified silicone rubber;

[0007] The modified silicone rubber includes polymer-grafted methyl vinyl silicone rubber, wherein the polymer includes polymers having oxygen-containing groups and aromatic groups;

[0008] In the polymer-grafted methyl vinyl silicone rubber, the content of the polymer is 1 to 10 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

[0009] In addition, the silicone-based pressure-sensitive adhesive according to this application may also have the following additional technical features:

[0010] In some embodiments, the polymer comprises polyphenylene ether. Preferably, in the polymer-grafted methyl vinyl silicone rubber, the content of polyphenylene ether is 4 to 6 parts by weight relative to 100 parts by weight of methyl vinyl silicone rubber.

[0011] In some embodiments, the polymer comprises an epoxy resin. Preferably, in the polymer-grafted methyl vinyl silicone rubber, the content of the epoxy resin is 4 to 6 parts by weight relative to 100 parts by weight of methyl vinyl silicone rubber.

[0012] In some embodiments, the epoxy resin is grafted onto the side chains of the methyl vinyl silicone rubber to form a three-dimensional network structure.

[0013] In some of these embodiments, the modified silicone rubber has the following structural formula:

[0014]

[0015] Wherein, R1 and R2 are each independently selected from C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 Alkenyl, ester, carboxyl, hydroxyl, ketone, ether, anhydride, alkoxy, epoxy, cyano, substituted or unsubstituted C 6-30 At least one of the aromatic groups, and at least one of R1 and R2 is selected from substituted or unsubstituted C. 6-30 Aromatic group;

[0016] The n is an integer from 10 to 50000.

[0017] In some of these embodiments, the substituted or unsubstituted C 6-30 The aromatic group includes at least one of phenyl, biphenyl, naphthyl, indole, phenanthryl, indene, anthracene, or fluorenyl.

[0018] In some of these embodiments, the replaced C 6-30 The aromatic group is selected from phenyl, and the substituents include C. 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ether, alkoxy, or epoxy groups.

[0019] In some of these embodiments, at least one of R1 and R2 is selected from the alternative C. 6-30 Aromatic group, the substituted C 6-30 The aromatic group is selected from phenyl, and the substituents include C. 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ether, alkoxy, or epoxy groups.

[0020] In some embodiments, at least one of R1 and R2 is selected from the following groups:

[0021]

[0022] In some embodiments, the number-average molecular weight of the modified silicone rubber is 400,000 to 800,000.

[0023] In some embodiments, the viscosity of the modified silicone rubber is 100–200,000 mPa·s.

[0024] In some embodiments, the silicone pressure-sensitive adhesive comprises the following components in parts by weight: 50-90 parts modified silicone rubber, 10-45 parts silicone resin, 0.05-5 parts crosslinking agent, and 0.01-3 parts catalyst.

[0025] In some embodiments, the silicone pressure-sensitive adhesive comprises the following components in parts by weight: 60-80 parts modified silicone rubber, 20-35 parts silicone resin, 0.1-3 parts crosslinking agent, and 0.05-1 part catalyst.

[0026] In some embodiments, the crosslinking agent comprises a hydrogen-containing silicone oil. Preferably, the hydrogen-containing silicone oil comprises at least one of a double-ended vinyl silicone oil or a methyl-terminated hydrogen-containing silicone oil. Preferably, the hydrogen content of the hydrogen-containing silicone oil is 0.1% to 1.5%.

[0027] In some embodiments, the catalyst comprises a platinum catalyst. Preferably, the platinum catalyst has a platinum content of 1000 ppm to 10000 ppm.

[0028] In some embodiments, the silicone resin includes at least one of methyl MQ silicone resin, vinyl MQ silicone resin, methyl vinyl MQ silicone resin, and phenyl MDQ silicone resin.

[0029] In some embodiments, the preparation of the silicone-based pressure-sensitive adhesive includes:

[0030] Modified silicone rubber, silicone resin, crosslinking agent, catalyst and diluent are mixed to prepare silicone pressure-sensitive adhesive paste;

[0031] The silicone-based pressure-sensitive adhesive paste is coated onto a carrier and then cured by heating to obtain the silicone-based pressure-sensitive adhesive.

[0032] In some embodiments, the diluting solvent includes at least one of toluene, xylene, or ethyl acetate. Preferably, the diluting sol comprises ethyl acetate and toluene in a mass ratio of (1-5):(1-5).

[0033] In some of these embodiments, the heating temperature for heat curing is 50°C to 170°C.

[0034] In some of these embodiments, the coating speed is 1 to 20 m / min.

[0035] In some embodiments, the energy storage modulus of the silicon-based pressure-sensitive adhesive is 200 kPa to 300 kPa.

[0036] In some embodiments, the loss factor of the silicon-based pressure-sensitive adhesive is 0.05 to 1.8.

[0037] According to another aspect of this application, this application provides a buffer structure comprising the aforementioned silicone pressure-sensitive adhesive.

[0038] According to another aspect of this application, this application provides a display module, the display module including the aforementioned silicon-based pressure-sensitive adhesive, or including the aforementioned buffer structure.

[0039] According to another aspect of this application, this application provides a display device, the display device including the aforementioned silicon-based pressure-sensitive adhesive, or including the aforementioned buffer structure, or including the aforementioned display module.

[0040] Implementing the technical solution of the present invention has at least the following beneficial effects:

[0041] In this embodiment, the provided silicone-based pressure-sensitive adhesive includes modified silicone rubber, which comprises polymer-grafted methyl vinyl silicone rubber, wherein the polymer includes polymers containing oxygen-containing groups and aromatic groups. Thus, the modified silicone rubber obtained by modifying the silicone rubber increases the chain segment movement resistance, improves dynamic mechanical properties, and consequently significantly enhances the damping performance of the silicone-based pressure-sensitive adhesive. Applying this high-damping silicone-based pressure-sensitive adhesive to buffer structures and display modules can improve the back-side impact resistance and enhance the anti-film printing level of the display module.

[0042] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0043] Figure 1 The diagram shows a comparison of the loss factors of the silicone pressure-sensitive adhesive in Example 1 (after improvement) and Comparative Example 1 (before improvement). Detailed Implementation

[0044] The present application will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present application.

[0045] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges or individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0046] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0047] With the development of the display industry, electronic products such as mobile phones are increasingly susceptible to damage from mechanical vibrations, necessitating buffer protection for display modules. Currently, buffer protection for display modules mainly relies on the buffer structure on the back of the module. Some buffer structures use silicone-based pressure-sensitive adhesive materials instead of foam materials, which improves the buffering performance of the back of the display module while also reducing weight and thickness. In other words, the application of silicone-based pressure-sensitive adhesive materials can effectively reduce display defects caused by vibration and extend the service life of the device. However, the inventors of this application have discovered that while the buffer structure of silicone-based pressure-sensitive adhesive materials achieves weight and thickness reduction, it also brings new problems, such as increasing the risk of film printing. This is mainly because the existing silicone-based pressure-sensitive adhesive materials experience a rapid decrease in damping loss factor as the ambient temperature rises, leading to increased resonance intensity. This makes them unsuitable for the high-precision operating conditions of mobile phone products, which involve a wide frequency range and fluctuating high and low temperatures, thus affecting the back buffering performance and resulting in poor film printing.

[0048] In related technologies, to alleviate the aforementioned problems, improvements are mainly made by refining silicone-based pressure-sensitive adhesives, such as silicone gel materials. For example, existing technologies adjust the composition and structure of silicone gels, particularly the ratio of silicone rubber to silicone resin and the amount of crosslinking agent. However, most raw materials for existing silicone gels come from companies like Corning and Shin-Etsu, which primarily provide overall adhesive formulations, making it difficult and time-consuming to adjust individual components. Additionally, some existing technologies improve damping characteristics by adding carbon nanotubes to the silicone gel material system. While this method has some effect on improving damping performance, it also introduces uneven dispersion, resulting in poor carbon powder distribution on the adhesive surface in practical applications, thus affecting the actual application effect.

[0049] In view of this, given the low damping performance of existing silicone-based pressure-sensitive adhesive materials, display modules with attached silicone buffer materials cannot meet the demands of high-precision applications involving wide frequency ranges and alternating high and low temperatures. Through extensive research, the inventors of this application have provided a silicone-based pressure-sensitive adhesive, as well as a buffer structure, display module, and display device incorporating this silicone-based pressure-sensitive adhesive, thereby improving the damping performance of silicone-based pressure-sensitive adhesive materials. A detailed description of the technical solution is provided below.

[0050] In some embodiments, this application provides a silicone-based pressure-sensitive adhesive, which includes modified silicone rubber. The modified silicone rubber can be an existing silicone rubber modified by grafting a specific polymer, such as methyl vinyl silicone rubber modified by grafting a specific polymer.

[0051] Specifically, the modified silicone rubber includes polymer-grafted methyl vinyl silicone rubber, wherein the polymer includes polymers having oxygen-containing groups and aromatic groups; in the polymer-grafted methyl vinyl silicone rubber, the content of the polymer is 1 to 10 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

[0052] Optionally, the silicone-based pressure-sensitive adhesive in this application may be a silicone gel.

[0053] It should be understood that silicone rubber constitutes the largest proportion of the composition of silicone-based pressure-sensitive adhesives (such as silicone gels), determining the main damping properties of the silicone gel. Therefore, chemical modification of silicone rubber has become an important direction. According to polymer damping mechanisms, the internal friction of a material is closely related to the polymer molecular structure. Therefore, increasing the intermolecular chain interaction forces and improving the internal friction of the material is an important means to improve damping performance. Among silicone rubbers, methyl vinyl silicone rubber is currently a commonly used type. It has high stereoregularity, and the symmetrically substituted methyl groups are small in volume and have low steric hindrance, resulting in very low intramolecular friction and poor damping performance. Therefore, this invention chooses to modify methyl vinyl silicone rubber, which has the advantages of wide availability, low cost, and ease of modification, and can improve its damping performance. This invention improves its damping performance by introducing large-volume groups or increasing the number of side chains in the side chains of methyl vinyl silicone rubber to increase the resistance to chain segment movement, improve dynamic mechanical properties, and thus improve its damping performance.

[0054] Therefore, in this application, by modifying existing silicone rubber, such as methyl vinyl silicone rubber, a modified silicone rubber is obtained. This modified silicone rubber includes polymer grafted methyl vinyl silicone rubber, such as grafting large-volume substituents like phenyl into the methyl vinyl silicone rubber structure. The grafted polymer, especially the grafted polymer with oxygen-containing groups and aromatic groups, can be used to increase the chain segment movement resistance of the silicone gel system, improve the dynamic mechanical properties, and thus significantly improve the damping performance of silicone pressure-sensitive adhesives.

[0055] Furthermore, the modified silicone rubber provided by this invention, by utilizing grafted polymers, allows for a better match between the relaxation and steric hindrance of the molecular chains, thereby obtaining a silicone rubber damping material with a wider glass transition region and a higher dynamic loss factor, thus improving damping performance. Specifically, the introduction of large groups such as phenyl groups increases the steric hindrance of the methyl vinyl silicone rubber molecular chains, affecting the regularity of the silicone rubber molecular chains and increasing the internal friction of the molecular chain movement, thereby improving damping performance and broadening the effective damping temperature range. This allows it to meet the high-precision operating conditions of display modules with wide frequency ranges and alternating high and low temperatures, alleviating the problem of low damping performance of existing silicone gel materials and their inability to meet the high-precision operating conditions of display modules with wide frequency ranges and alternating high and low temperatures.

[0056] In polymer-grafted methyl vinyl silicone rubber, the polymer content is 1 to 10 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber, preferably 2 to 8 parts by mass, and more preferably 4 to 6 parts by mass. For example, the polymer content relative to 100 parts by mass of methyl vinyl silicone rubber can be any one of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 parts by mass, or a range between any two.

[0057] When grafting polymers containing oxygen-containing and aromatic groups into the structure of methyl vinyl silicone rubber, the number of bulky groups or side chains increases with the increase of polymer content, leading to increased chain segment movement resistance and a certain improvement in dynamic mechanical properties. Therefore, damping performance also increases, while adhesion may decrease slightly, and the back-side cushioning performance (buffer absorption rate) remains largely unchanged. Thus, when grafting polymers containing oxygen-containing and aromatic groups into the structure of methyl vinyl silicone rubber, controlling the polymer content to 1–10 parts by mass, especially 4–6 parts by mass, can give the silicone pressure-sensitive adhesive high damping and cushioning performance while maintaining sufficient adhesion.

[0058] Through in-depth research, the inventors have discovered that, in addition to meeting the above-mentioned design conditions, the performance of the silicone pressure-sensitive adhesive can be further improved if it can optionally meet one or more of the following conditions.

[0059] In some embodiments, the polymer is selected from polyphenylene ether, and polyphenylene ether is grafted into the structure of methyl vinyl silicone rubber. In this application, grafting a bulky substituent such as phenyl into the structure of methyl vinyl silicone rubber can significantly improve its damping performance, wherein the grafted bulky substituent structure can be polyphenylene ether.

[0060] Preferably, in the polymer-grafted methyl vinyl silicone rubber, the content of polyphenylene ether is 1 to 10 parts by weight relative to 100 parts by weight of methyl vinyl silicone rubber, preferably 4 to 6 parts by weight. For example, the content of polyphenylene ether can be 4 parts by weight, 5 parts by weight, 6 parts by weight, etc. More preferably, the content of polyphenylene ether is 5 parts by weight relative to 100 parts by weight of methyl vinyl silicone rubber. Adding about 5 wt% of polyphenylene ether structure to methyl vinyl silicone rubber can obtain a modified silicone rubber containing large-volume substituents such as phenyl groups, which can significantly improve its damping performance.

[0061] When polyphenylene ether (PPE) is grafted onto a methyl vinyl silicone rubber structure, the number of bulk groups or side chains increases with the increase of PPE content, leading to increased chain segment movement resistance and improved dynamic mechanical properties. Consequently, damping performance also increases, while adhesion may decrease slightly, and back-side cushioning performance remains largely unchanged. Therefore, when grafting PPE onto a methyl vinyl silicone rubber structure, controlling the PPE content to 4–6 parts by mass allows the silicone-based pressure-sensitive adhesive to possess high damping and cushioning performance while maintaining sufficient adhesion.

[0062] In some embodiments, the polymer is selected from epoxy resins, and epoxy resin is grafted into the structure of methyl vinyl silicone rubber.

[0063] Preferably, in the polymer-grafted methyl vinyl silicone rubber, the epoxy resin content is 1 to 10 parts by weight relative to 100 parts by weight of methyl vinyl silicone rubber, preferably 4 to 6 parts by weight. For example, the epoxy resin content can be 4 parts by weight, 5 parts by weight, 6 parts by weight, etc.

[0064] When grafting epoxy resin into a methyl vinyl silicone rubber structure, the epoxy resin content is controlled at 4 to 6 parts by weight, which can give the silicone pressure-sensitive adhesive high damping and buffering performance, while maintaining sufficient adhesion.

[0065] In some preferred embodiments, epoxy resin is grafted onto the side chains of methyl vinyl silicone rubber to form a three-dimensional network structure or an interpenetrating network structure.

[0066] In this application, an interpenetrating epoxy structure is grafted or formed on the side chain groups of methyl vinyl silicone rubber. In this way, the modification method not only grafts a small segment structure onto the methyl vinyl silicone rubber, but also forms an interpenetrating network structure, thereby making the adjustment space larger and the improvement effect more obvious. That is, the formation of the interpenetrating network structure is more conducive to improving the damping performance of the modified silicone rubber.

[0067] It should be understood that in some embodiments, polyphenylene ether may be grafted into the structure of the methyl vinyl silicone rubber. In other embodiments, epoxy resin may be grafted into the structure of the methyl vinyl silicone rubber. Of course, this application is not limited to these; in modified silicone rubber, both polyphenylene ether and epoxy resin may be grafted into the structure of the methyl vinyl silicone rubber simultaneously to further improve damping performance, thereby improving the buffering performance of the buffer structure and improving the film printing effect.

[0068] Therefore, based on the above, this invention improves the damping performance of methyl vinyl silicone rubber by adding an appropriate amount of polyphenylene ether structure to methyl vinyl silicone rubber, thereby generating a modified silicone rubber containing large-volume substituents such as phenyl groups. Alternatively, by grafting epoxy resin onto the side chains of methyl vinyl silicone rubber to form an interpenetrating network structure, the adjustment space is larger, and the improvement effect is more significant, thus further enhancing the damping performance. Applying this modified silicone rubber with high damping performance to silicone-based pressure-sensitive adhesives, and then applying these adhesives to buffer structures and display modules, can improve the buffering performance of the buffer structure, i.e., enhance the back-side buffering performance or back-side impact resistance, thereby improving the film printing effect, and also avoids the problem of uneven dispersion.

[0069] Among them, the buffer absorption rate (back buffer performance) refers to the lowest height value at which no display 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.

[0070] Specifically, in some embodiments, the structural formula of the modified silicone rubber can be as follows:

[0071]

[0072] Among them, R1 and R2 are each independently selected from C. 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 Alkenyl, ester, carboxyl, hydroxyl, ketone, ether, anhydride, alkoxy, epoxy, cyano, substituted or unsubstituted C 6-30 At least one of the aromatic groups, and at least one of R1 and R2 is selected from substituted or unsubstituted C. 6-30 Aromatic group.

[0073] In this application, the graft polymer in the modified silicone rubber can be polyphenylene ether or epoxy resin, or the modified silicone rubber can also have the structural formula shown above, and in the above structural formula, R1 can contain substituted or unsubstituted C. 6-30 Aromatic group, R1 may also contain C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ketone, ether, anhydride, alkoxy, epoxy, and cyano groups, and R1 preferably contains an aromatic group and an oxygen-containing group; or, R2 may contain a substituted or unsubstituted C group. 6-30 Aromatic group, R2 may also contain C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 R2 comprises at least one of alkenyl, ester, carboxyl, hydroxyl, ketone, ether, anhydride, alkoxy, epoxy, and cyano groups, and preferably includes an aromatic group and an oxygen-containing group.

[0074] In this application, R1 and R2 may be the same or different.

[0075] In the above structural formula, n is an integer from 10 to 50,000; as an example, n can be an integer from 10 to 40,000, or an integer from 50 to 40,000, or an integer from 100 to 30,000, or an integer from 100 to 20,000, or an integer from 500 to 10,000. The specific value of n can be adjusted according to the molecular weight of the modified silicone rubber obtained.

[0076] The term "carboxyl group" refers to the COOH group.

[0077] The term "hydroxyl group" refers to the -OH group.

[0078] The term "ester group" refers to the -COOR3 group, where R3 is selected from alkyl groups that are substituted or unsubstituted.

[0079] Similarly, the terms “phenyl ring (phenyl), alkyl, cycloalkyl, alkenyl, ether group, ketone group, alkoxy, epoxy” used have the meanings commonly understood in the art and will not be described in detail here.

[0080] Optionally, in some cases, R1 is selected from unsubstituted C. 6-30 The aromatic group, R1, is further selected from at least one of ester, carboxyl, ketone, ether, anhydride, alkoxy, hydroxyl, and epoxy groups; furthermore, R1 may optionally include C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl and cyano groups.

[0081] Alternatively, in other cases, R1 is selected from the substituted C. 6-30 Aromatic groups, substituents including C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ether, alkoxy, or epoxy groups; further, R1 may optionally include ester, carboxyl, hydroxyl, ketone, ether, anhydride, alkoxy, epoxy, C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl and cyano groups.

[0082] Optionally, in some cases, R2 is selected from unsubstituted C. 6-30 The aromatic group, R2, is further selected from at least one of the following groups: ester group, carboxyl group, hydroxyl group, ketone group, ether group, acid anhydride group, alkoxy group, and epoxy group; furthermore, R2 may optionally include C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl and cyano groups.

[0083] Alternatively, in other cases, R2 is selected from the substituted C. 6-30 Aromatic groups, substituents including C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ether, alkoxy, or epoxy groups; further, R2 may optionally include ester, carboxyl, hydroxyl, ketone, ether, anhydride, alkoxy, epoxy, C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl and cyano groups.

[0084] In some embodiments, substituted or unsubstituted C 6-30 The aromatic group includes at least one of phenyl, biphenyl, naphthyl, indole, phenanthryl, indene, anthracene, or fluorenyl.

[0085] Preferred, alternative C 6-30 The aromatic group is selected from phenyl, and the substituents include C. 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ether, alkoxy, or epoxy groups.

[0086] In some embodiments, at least one of R1 and R2 is selected from the substituted C 6-30 Aromatic group, substituted C 6-30The aromatic group is selected from phenyl, and the substituents include C. 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ether, alkoxy, or epoxy groups. Preferably, the substituent includes at least one of ester, hydroxyl, carboxyl, ether, alkoxy, or epoxy groups. Further, the substituent may also include C... 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of the alkenyl groups.

[0087] In this application, R1 can be selected from the self-replaced C. 6-30 Aromatic group, or R2 optionally self-substituted C 6-30 Aromatic group, or both R1 and R2 may be self-substituted C 6-30 Aromatic group.

[0088] Preferably, in some embodiments, at least one of R1 and R2 is selected from the following groups:

[0089]

[0090] The above-mentioned epoxy resin structure containing epoxy groups and benzene rings can be grafted onto the side chains of methyl vinyl silicone rubber to form an interpenetrating network structure, thereby allowing for greater adjustment space and more obvious improvement effect. That is, the formation of the interpenetrating network structure is more conducive to improving the damping performance of modified silicone rubber.

[0091] It should be noted that, due to the relatively large size of the epoxy resin structures containing epoxy groups and benzene rings, it is not advisable to introduce too many of these groups into methyl vinyl silicone rubber, otherwise it will affect the basic properties of the modified silicone rubber. Therefore, only one of the aforementioned epoxy resin structures containing epoxy groups and benzene rings can be introduced into the side chain of methyl vinyl silicone rubber, which can improve the damping performance while ensuring the basic properties of the silicone rubber.

[0092] In some embodiments, the number-average molecular weight of the modified silicone rubber is 400,000 to 800,000. As an example, the number-average molecular weight of the modified silicone rubber can be any one of 400,000, 450,000, 500,000, 600,000, 650,000, 700,000, or 800,000, or a range between any two.

[0093] In this paper, the term "number-average molecular weight" refers to the sum of the products of the mole fractions of molecules of different molecular weights in a polymer and their corresponding molecular weights.

[0094] In some embodiments, the viscosity of the modified silicone rubber is 100–200,000 mPa·s. As an example, the viscosity of the modified silicone rubber can be any one of the following values, or a range between any two: 100 mPa·s, 500 mPa·s, 1000 mPa·s, 5000 mPa·s, 100000 mPa·s, 15000 mPa·s, 20000 mPa·s, 50000 mPa·s, 100000 mPa·s, and 200000 mPa·s.

[0095] By ensuring that the number-average molecular weight and viscosity of the modified silicone rubber are within the above-mentioned range, the adhesiveness of the modified silicone rubber can be guaranteed, and the damping performance can be improved, thereby enhancing the buffering performance and further improving the film printing effect, thus balancing both buffering and film printing performance.

[0096] In some embodiments, the silicone pressure-sensitive adhesive comprises the following components in parts by weight:

[0097] The mixture contains 50-90 parts of modified silicone rubber, 10-45 parts of silicone resin, 0.05-5 parts of crosslinking agent, and 0.01-3 parts of catalyst.

[0098] In this application, the main component of the silicone-based pressure-sensitive adhesive is the aforementioned modified silicone rubber. In addition, the silicone-based pressure-sensitive adhesive may also include silicone resin, crosslinking agent, and catalyst. That is, the silicone-based pressure-sensitive adhesive can be mainly composed of modified silicone rubber, silicone resin, crosslinking agent, and catalyst.

[0099] In the silicone-based pressure-sensitive adhesive provided in this embodiment, the modified silicone rubber comprises 50 to 90 parts by weight, for example, 50, 55, 60, 65, 68, 70, 72, 75, 80, and 90 parts. Modified silicone rubber is the basic substance forming the silicone-based pressure-sensitive adhesive and affects its fundamental properties. By limiting the mass content of modified silicone rubber within the above range, the synergistic effect between modified silicone rubber and other components can be better utilized, further improving the overall performance of the silicone gel.

[0100] In the silicone-based pressure-sensitive adhesive provided in this embodiment, the mass fraction of silicone resin is 10 to 45 parts, for example, 10 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, etc. Adding an appropriate amount of silicone resin to the silicone-based pressure-sensitive adhesive helps to ensure the strength, flexibility, and adhesion of the silicone-based pressure-sensitive adhesive.

[0101] In the silicone-based pressure-sensitive adhesive provided in this embodiment, the crosslinking agent comprises 0.05 to 5 parts by mass, for example, 0.05 parts, 0.1 parts, 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, etc. The catalyst comprises 0.01 to 3 parts by mass, for example, 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 2 parts, 2.5 parts, 3 parts, etc.

[0102] Preferably, in some embodiments, the silicone pressure-sensitive adhesive comprises the following components in parts by weight:

[0103] The mixture contains 60-80 parts of modified silicone rubber, 20-35 parts of silicone resin, 0.1-3 parts of crosslinking agent, and 0.05-1 part of catalyst.

[0104] More preferably, in some embodiments, the silicone pressure-sensitive adhesive comprises the following components in parts by weight:

[0105] The mixture contains 65-75 parts modified silicone rubber, 25-30 parts silicone resin, 0.4-0.6 parts crosslinking agent, and 0.2-0.5 parts catalyst.

[0106] By reasonably adjusting and optimizing the content of each component in silicone-based pressure-sensitive adhesives, the synergistic effect between the components can be fully utilized to further improve the damping performance or overall performance of silicone-based pressure-sensitive adhesives, while reducing the production cost of silicone-based pressure-sensitive adhesives.

[0107] In some embodiments, the crosslinking agent includes hydrogen-containing silicone oil. Preferably, the hydrogen-containing silicone oil includes, but is not limited to, at least one of dual-terminated vinyl silicone oil or methyl-terminated hydrogen-containing silicone oil.

[0108] Preferably, the hydrogen content of the hydrogen-containing silicone oil is 0.1% to 1.5%, and exemplary values ​​are 0.1%, 0.2%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, etc.

[0109] In silicone-based pressure-sensitive adhesives, hydrogen-containing silicone oil acts as a crosslinking agent for the silicone gel, determining the type and density of crosslinking bonds and having a decisive impact on the product performance of the silicone gel. The silanol groups in hydrogen-containing silicone oil can undergo addition crosslinking reactions with the vinyl groups in vinyl silicone oil. Limiting the amount of hydrogen-containing silicone oil added and its hydrogen content can improve the degree of crosslinking of the silicone gel and enhance its cushioning performance.

[0110] In some embodiments, the catalyst includes a platinum catalyst; preferably, the platinum content of the platinum catalyst is 1000ppm to 10000ppm, exemplarily 1000ppm, 2000ppm, 5000ppm, 8000ppm, 10000ppm, etc.

[0111] Of course, this application only uses platinum catalyst as an example of catalyst material in its description, but this application is not limited to this. In some other embodiments, the catalyst can also be other similar materials or materials with excellent catalytic performance, which will not be listed here.

[0112] In some embodiments, the silicone resin includes at least one of methyl MQ silicone resin, vinyl MQ silicone resin, methyl vinyl MQ silicone resin, and phenyl MDQ silicone resin.

[0113] In this application, the MQ resin is composed of monofunctional repeating units (R3SiO2). 1 / 2 (abbreviated as M unit) and four functional chain units (SiO) 4 / 2 It is composed of a special organic / inorganic hybrid polyorganosiloxane with a structure ratio of Q unit (abbreviated as Q unit).

[0114] In silicone-based pressure-sensitive adhesives, the synergistic use of the aforementioned silicone resins can better improve the adhesion and colloid strength of the silicone gel.

[0115] Of course, the description in this application only uses silicone resins such as methyl MQ silicone resin, vinyl MQ silicone resin, methyl vinyl MQ silicone resin, and phenyl MDQ silicone resin as examples for illustration. However, this application is not limited to these. In some other embodiments, the silicone resin can also be other similar materials or materials with excellent properties, which will not be listed here.

[0116] In some embodiments, the preparation of the silicone-based pressure-sensitive adhesive includes:

[0117] Modified silicone rubber, silicone resin, crosslinking agent, catalyst and diluent are mixed to prepare silicone pressure-sensitive adhesive paste;

[0118] Silicone pressure-sensitive adhesive paste is coated onto a carrier and cured by heating to obtain silicone pressure-sensitive adhesive.

[0119] It should be noted that the silicone-based pressure-sensitive adhesive of this application can be prepared by coating molding, which has the advantages of high efficiency and yield. Specific operating methods and conditions for coating molding of the silicone-based pressure-sensitive adhesive can be referred to relevant prior art, and this application does not limit them. Furthermore, the above-mentioned modified silicone rubber can also be prepared by referring to conventional polymer grafting modification methods, and this application does not limit it either.

[0120] In some embodiments, the diluent includes at least one of toluene, xylene, or ethyl acetate.

[0121] Preferably, the diluted sol comprises toluene and ethyl acetate, wherein the mass ratio of ethyl acetate to toluene is (1-5):(1-5), and more preferably, the mass ratio of ethyl acetate to toluene is 3:2.

[0122] By using two solvents with different boiling points, good leveling and curing properties can be achieved, thereby improving the appearance and product performance uniformity of silicone gel.

[0123] In some embodiments, the heating temperature for heat curing is 50℃ to 170℃; optionally, multiple sections can be used for heat curing, such as at least five or at least seven sections. For example, the heating temperature of the first section can be 50℃ to 70℃, the second section 130℃ to 140℃, the third section 160℃ to 170℃, the fourth section 160℃ to 170℃, the fifth section 150℃ to 155℃, the sixth section 150℃ to 155℃, the seventh section 150℃ to 155℃, and the eighth section 115℃ to 120℃, etc.

[0124] In some embodiments, the coating speed during the preparation of the silicone pressure-sensitive adhesive is 1 to 20 m / min; exemplary speeds include 1 m / min, 2 m / min, 5 m / min, 8 m / min, 10 m / min, 15 m / min, 20 m / min, etc.

[0125] In some embodiments, the energy storage modulus of the silicone-based pressure-sensitive adhesive provided in this application is 200 kPa to 300 kPa. This energy storage modulus refers to the energy storage modulus at room temperature, such as the energy storage modulus at 25°C. The energy storage modulus range at 25°C is 200 kPa to 300 kPa, and exemplary values ​​are 200 kPa, 220 kPa, 240 kPa, 250 kPa, 280 kPa, 300 kPa, etc.

[0126] In some embodiments, the loss factor of the silicon-based pressure-sensitive adhesive provided in this application is 0.05 to 1.8.

[0127] It is evident that the silicon-based pressure-sensitive adhesive of this application has a relatively wide or high loss factor, indicating that the present invention improves the damping performance of the silicon-based pressure-sensitive adhesive, thereby improving the back impact resistance of the buffer structure containing the silicon-based pressure-sensitive adhesive and enhancing the anti-film printing level of the display module.

[0128] In some embodiments, this application also provides a buffer structure comprising the silicone pressure-sensitive adhesive provided in any of the above embodiments.

[0129] Specifically, the silicone-based pressure-sensitive adhesive substrate may include a silicone gel substrate.

[0130] Using silicone gel as the main material for the buffer structure allows the buffer structure to have good buffering performance and film printing effect.

[0131] It should also be noted that the buffer structure of this application can be applied in display modules. The buffer structure may only include the silicon-based pressure-sensitive adhesive provided in this application, or it may include other materials or structures known in the art. This application does not make any special limitations in this regard. The specific configuration of the buffer structure can be referred to the relevant prior art.

[0132] Since the buffer structure of the present invention includes the aforementioned silicon-based pressure-sensitive adhesive, the display device of the present invention has the beneficial effects of the aforementioned silicon-based pressure-sensitive adhesive, which will not be repeated here.

[0133] In some embodiments, this application also provides a display module, which includes the silicon-based pressure-sensitive adhesive provided in any of the above embodiments, or includes the buffer structure provided in any of the above embodiments.

[0134] Optionally, the display module may also include a display panel located on one side of the buffer structure.

[0135] In practice, the buffer structure can be located on the back of the display panel (the side of the display panel substrate away from the light-emitting side) to provide buffer protection.

[0136] Optionally, the display module may also include a support layer located on the side of the buffer structure opposite to the display panel. Alternatively, in specific applications, the support layer may be a film layer made of copper foil.

[0137] Since the display module of this embodiment includes the aforementioned silicon-based pressure-sensitive adhesive, the display device of this embodiment has the beneficial effects of the aforementioned silicon-based pressure-sensitive adhesive, which will not be elaborated further here.

[0138] In some embodiments, this application also provides a display device, which includes the silicon-based pressure-sensitive adhesive provided in any of the above embodiments, or includes the buffer structure provided in any of the above embodiments, or includes the display module provided in any of the above embodiments.

[0139] In this application, the display device can be a mobile phone, a tablet computer, a digital camera, an e-reader, a television, an access control system, a smart landline phone, a control console, or other devices with display functions, which will not be described in detail here.

[0140] Since the display device of the present invention includes the display panel described above, the display device of the present invention has the beneficial effects of the display panel described above, which will not be repeated here.

[0141] To better understand this invention, the specific implementation process will be described in detail below with specific implementation methods. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in this field or in accordance with the product specification.

[0142] Example 1

[0143] Silicone-based pressure-sensitive adhesives include the following raw materials:

[0144] Modified silicone rubber, silicone resin (methyl MQ silicone resin and vinyl MQ silicone resin), crosslinking agent (hydrogen-containing silicone oil), catalyst (platinum catalyst) and diluent;

[0145] The mass ratio of modified silicone rubber, silicone resin, crosslinking agent, and catalyst is 70:30:0.5:0.3.

[0146] The diluted sol consists of ethyl acetate and toluene in a mass ratio of 3:2.

[0147] The modified silicone rubber is polyphenylene ether grafted with methyl vinyl silicone rubber, and the content of polyphenylene ether is 5 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

[0148] Example 2

[0149] This embodiment is based on Example 1, and the preparation method is the same as in Example 1. The difference lies in the modified silicone rubber used in the silicone-based pressure-sensitive adhesive, as detailed below:

[0150] The modified silicone rubber is polyphenylene ether grafted with methyl vinyl silicone rubber, and the content of polyphenylene ether is 2 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

[0151] Example 3

[0152] This embodiment is based on Example 1, and the preparation method is the same as in Example 1. The difference lies in the modified silicone rubber used in the silicone-based pressure-sensitive adhesive, as detailed below:

[0153] The modified silicone rubber is polyphenylene ether grafted with methyl vinyl silicone rubber, and the content of polyphenylene ether is 8 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

[0154] Example 4

[0155] This embodiment is based on Example 1, and the preparation method is the same as in Example 1. The difference lies in the modified silicone rubber used in the silicone-based pressure-sensitive adhesive, as detailed below:

[0156] The modified silicone rubber is epoxy resin grafted onto methyl vinyl silicone rubber. The epoxy resin is grafted onto the side chains of the methyl vinyl silicone rubber to form an interpenetrating epoxy structure. The content of epoxy resin is 5 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

[0157] The structure of epoxy resin is shown below:

[0158]

[0159] Example 5

[0160] This embodiment is based on Example 1, and the preparation method is the same as in Example 1. The difference lies in the modified silicone rubber used in the silicone-based pressure-sensitive adhesive, as detailed below:

[0161] The modified silicone rubber is epoxy resin grafted onto methyl vinyl silicone rubber. The epoxy resin is grafted onto the side chains of the methyl vinyl silicone rubber to form an interpenetrating epoxy structure. The content of epoxy resin is 2 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

[0162] The structure of epoxy resin is shown below:

[0163]

[0164] Example 6

[0165] This embodiment is based on Example 1, and the preparation method is the same as in Example 1. The difference lies in the modified silicone rubber used in the silicone-based pressure-sensitive adhesive, as detailed below:

[0166] The modified silicone rubber is a polymer-grafted methyl vinyl silicone rubber; the polymer content is 5 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

[0167] The structural formula of the modified silicone rubber is shown below:

[0168]

[0169] Wherein, R1 is a C10 epoxy-substituted C8 aromatic derivative; the structural formula of R2 is shown below:

[0170] n is 2500.

[0171] Comparative Example 1

[0172] Silicone-based pressure-sensitive adhesives include the following raw materials:

[0173] Silicone rubber, silicone resin, crosslinking agent, catalyst, and diluent;

[0174] The mass ratio of silicone rubber, silicone resin, crosslinking agent, and catalyst is 70:30:0.5:0.3.

[0175] The diluted sol consists of ethyl acetate and toluene in a mass ratio of 3:2;

[0176] The silicone rubber is unmodified methyl vinyl silicone rubber.

[0177] Performance testing

[0178] The performance of the silicone pressure-sensitive adhesives prepared in the above embodiments and comparative examples was tested, specifically including:

[0179] (1) Storage modulus (room temperature) test: The test was conducted using a rheometer (Anton Paar series rheometer); the test conditions included adding the sample into the rheometer, letting it stand, and then processing it. The pre-compression normal force was 0.5 N, the thickness was 1 mm (mass production thickness can be stacked to 1 mm, and high pressure degassing treatment can be performed after stacking), the diameter was 8 mm, the frequency was 1 Hz, the temperature range was (-60 to 100℃), and the strain was 0.50%.

[0180] (2) Tensile modulus test: The material of each sample tested is 70mm*5mm*1mm (mass production thickness can be stacked to 1mm, and high pressure degassing treatment is performed after stacking). The test conditions include: 1. Using pneumatic clamps; 2. Test span 30mm, tensile speed 300mm / min; 3. A total of 3 groups are tested. The stress value at 100% strain is calculated from the result of the centrally damaged sample. If there are less than 3 samples, the test continues until 3 valid data can be selected.

[0181] (3) Adhesion test: The materials of each sample tested were at least 240 mm in length and at least 25 mm in width; the test conditions included: 1. The long side (stretched side) was made of 50 μm PET, first bonded to silicone, and rolled twice with a 2Kg roller (one round trip counts as one), then the silicone was bonded to CU / PET / PI, rolled twice with a 2Kg roller (one round trip counts as one), and left to stand at 25℃ for 24 hours; 2. 3M 55236 high temperature double-sided tape was used to bond to 100mm*25mm*2mm float white glass to test the 180° peel force, and peeled at a speed of 300mm / min; 3. A total of 3 groups were tested, and the average peel force (adhesion force) was calculated.

[0182] (4) Back cushioning performance test: The test tool is a stainless steel ball (14mm in diameter, 11.2g stainless steel ball 5.5cm); Sample condition for testing: pure silicone film test, the sample is attached to the surface of the sensor platform, the copper sheet side is used as the impact surface for data acquisition, the sensor is preferably a piezoelectric ceramic sensor, the range is >500N, and the sampling frequency is recommended to be >100kHz.

[0183] The test results are shown in Table 1 below.

[0184] Table 1

[0185]

[0186] As can be seen from Table 1, compared with Comparative Example 1, that is, compared with unmodified silicone rubber, the present invention improves the room temperature energy storage modulus and tensile modulus of silicone pressure-sensitive adhesive by adding modified silicone rubber to the silicone pressure-sensitive adhesive, and also improves the back cushioning performance.

[0187] also, Figure 1 The diagram shows a comparison of the loss factors of the silicon-based pressure-sensitive adhesives of Example 1 (after improvement) and Comparative Example 1 (before improvement). The loss factor can be tested using the rheometer described above. Figure 1 As can be seen, the present invention improves the loss factor, thereby improving the damping performance of the silicon-based pressure-sensitive adhesive. This can alleviate the problem that existing silicon gel materials have low damping performance and cannot meet the working conditions of high-precision fields with wide frequency range and high and low temperature alternation in display modules.

[0188] The parts of this invention not described in detail are techniques known to those skilled in the art.

[0189] The basic principles of the present invention have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in the present invention are merely examples and not limitations, and should not be considered as essential features of each embodiment of the present invention. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the present invention to the necessity of employing the aforementioned specific details.

[0190] It should be noted that the terms "and / or" or " / " used herein are merely descriptions of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The singular forms "a," "described," and "the" used in the embodiments of the invention and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0191] In the detailed description and claims, a list of items connected by the terms "at least one of," "at least one of," "at least one of," or other similar terms may mean any combination of the listed items. For example, if items A and B are listed, then the phrase "at least one of A and B" means only A; only B; or A and B. In another example, if items A, B, and C are listed, then the phrase "at least one of A, B, and C" means only A; or only B; only C; A and B (excluding C); A and C (excluding B); B and C (excluding A); or all of A, B, and C. Item A may contain a single element or multiple elements. Item B may contain a single element or multiple elements. Item C may contain a single element or multiple elements.

[0192] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A silicone-based pressure-sensitive adhesive, characterized in that, The silicone-based pressure-sensitive adhesive includes modified silicone rubber; The modified silicone rubber includes polymer-grafted methyl vinyl silicone rubber, wherein the polymer includes polymers having oxygen-containing groups and aromatic groups; In the polymer-grafted methyl vinyl silicone rubber, the content of the polymer is 1 to 10 parts by mass relative to 100 parts by mass of methyl vinyl silicone rubber.

2. The silicone-based pressure-sensitive adhesive according to claim 1, characterized in that, The polymer comprises polyphenylene ether; preferably, in the polymer-grafted methyl vinyl silicone rubber, the content of polyphenylene ether is 4 to 6 parts by weight relative to 100 parts by weight of methyl vinyl silicone rubber; and / or, The polymer includes epoxy resin; preferably, in the polymer grafted with methyl vinyl silicone rubber, the content of epoxy resin is 4 to 6 parts by weight relative to 100 parts by weight of methyl vinyl silicone rubber. Preferably, the epoxy resin is grafted onto the side chains of the methyl vinyl silicone rubber to form a three-dimensional network structure.

3. The silicone-based pressure-sensitive adhesive according to claim 1, characterized in that, The structural formula of the modified silicone rubber is shown below: Wherein, R1 and R2 are each independently selected from C 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 Alkenyl, ester, carboxyl, hydroxyl, ketone, ether, anhydride, alkoxy, epoxy, cyano, substituted or unsubstituted C 6-30 At least one of the aromatic groups, and at least one of R1 and R2 is selected from substituted or unsubstituted C. 6-30 Aromatic group; The n is an integer from 10 to 50000; Preferably, the substituted or unsubstituted C 6-30 The aromatic group includes at least one of phenyl, biphenyl, naphthyl, indole, phenanthryl, indene, anthracene, or fluorenyl. Preferably, the substituted C 6-30 The aromatic group is selected from phenyl, and the substituents include C. 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ether, alkoxy, or epoxy groups; Preferably, at least one of R1 and R2 is selected from the substituted C 6-30 Aromatic group, the substituted C 6-30 The aromatic group is selected from phenyl, and the substituents include C. 1-20 Alkyl, C 3-20 cycloalkyl, C 2-20 At least one of alkenyl, ester, carboxyl, hydroxyl, ether, alkoxy, or epoxy groups; Preferably, at least one of R1 and R2 is selected from the following groups:

4. The silicone-based pressure-sensitive adhesive according to claim 1, characterized in that, The modified silicone rubber has a number-average molecular weight of 400,000 to 800,000; and / or, The viscosity of the modified silicone rubber is 100–200,000 mPa·s.

5. The silicone-based pressure-sensitive adhesive according to any one of claims 1 to 4, characterized in that, The silicone-based pressure-sensitive adhesive comprises the following components in parts by weight: The mixture contains 50-90 parts modified silicone rubber, 10-45 parts silicone resin, 0.05-5 parts crosslinking agent, and 0.01-3 parts catalyst. Preferably, the silicone-based pressure-sensitive adhesive comprises the following components in parts by weight: The mixture contains 60-80 parts of modified silicone rubber, 20-35 parts of silicone resin, 0.1-3 parts of crosslinking agent, and 0.05-1 part of catalyst.

6. The silicone-based pressure-sensitive adhesive according to claim 5, characterized in that, The crosslinking agent comprises hydrogen-containing silicone oil; preferably, the hydrogen-containing silicone oil comprises at least one of dual-terminated vinyl silicone oil or methyl-terminated hydrogen-containing silicone oil; preferably, the hydrogen content of the hydrogen-containing silicone oil is 0.1% to 1.5%; and / or, The catalyst includes a platinum catalyst; preferably, the platinum content of the platinum catalyst is 1000 ppm to 10000 ppm; and / or, The silicone resin includes at least one of methyl MQ silicone resin, vinyl MQ silicone resin, methyl vinyl MQ silicone resin, and phenyl MDQ silicone resin.

7. The silicone-based pressure-sensitive adhesive according to claim 5, characterized in that, The preparation of the silicone-based pressure-sensitive adhesive includes: Modified silicone rubber, silicone resin, crosslinking agent, catalyst and diluent are mixed to prepare silicone pressure-sensitive adhesive paste; The silicone-based pressure-sensitive adhesive paste is coated onto a carrier and cured by heating to obtain the silicone-based pressure-sensitive adhesive. Preferably, the diluent includes at least one of toluene, xylene, or ethyl acetate; preferably, the diluent sol includes ethyl acetate and toluene in a mass ratio of (1-5):(1-5). Preferably, the heating temperature for heat curing is 50℃~170℃; Preferably, the coating speed is 1-20 m / min; Preferably, the storage modulus of the silicone pressure-sensitive adhesive is 200 kPa to 300 kPa; Preferably, the loss factor of the silicon-based pressure-sensitive adhesive is 0.05 to 1.

8.

8. A buffer structure, characterized in that, The buffer structure comprises the silicone pressure-sensitive adhesive as described in any one of claims 1 to 7.

9. A display module, characterized in that, The display module includes the silicon-based pressure-sensitive adhesive as described in any one of claims 1 to 7, or includes the buffer structure as described in claim 8.

10. A display device, characterized in that, The display device includes the silicon-based pressure-sensitive adhesive as described in any one of claims 1 to 7, or the buffer structure as described in claim 8, or the display module as described in claim 9.

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