Single-component epoxy adhesive as well as preparation method and application thereof

Abstract

The invention relates to a single-component epoxy adhesive as well as a preparation method and application thereof. The single-component epoxy adhesive is prepared from the following components in parts by weight: 35 to 45 parts of bisphenol epoxy resin, 5 to 20 parts of polyurethane modified epoxy resin, 20 to 30 parts of curing agent, 0.1 to 1 part of fluorocarbon surfactant and 0.1 to 1 part of flatting agent. According to the single-component epoxy adhesive provided by the invention, the leveling agent and the fluorocarbon surfactant are introduced into an epoxy resin system, so that the problem that an epoxy adhesive on the market at present is easy to diffuse and separate out is solved, and the single-component epoxy adhesive also has excellent adhesive property, ageing resistance and reliability.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, and in particular to a one-component epoxy adhesive, its preparation method, and its application. Background Technology

[0002] Epoxy resin adhesives are among the most widely used adhesives due to their strong adhesion, good chemical stability, and excellent insulation properties. Commonly used epoxy resin adhesives are generally two-component or multi-component adhesives, requiring preparation before use. This not only complicates construction but also, due to the high viscosity of the components, makes thorough mixing difficult, significantly reducing the performance of the cured product. In the microelectronics industry, where the amount of adhesive dispensed is very small and the uniformity of the mixture is crucial, single-component epoxy adhesives are often used. These adhesives involve adding a latent curing agent to the epoxy resin. At room temperature, the agent is stable and does not react with the epoxy resin, only reacting and curing upon exposure to heat, light, and humidity. The curing conditions are controllable, offering long-term applicability, good storage stability, and eliminating the problem of uneven mixing during use. These adhesives are widely used in the microelectronics industry.

[0003] In the bonding applications of module lenses, module manufacturers perform plasma treatment on the surface of engineering plastics (LCP) to obtain stronger adhesion. This results in a very rough surface, creating many capillary gaps. Adhesive, before it has fully cured at room temperature or after heating, can easily migrate and precipitate onto these gaps. If this migration occurs at the solder joints, it will affect subsequent welding; if it migrates onto the lens, it will contaminate the lens and cause product defects.

[0004] CN114292612A discloses a one-component epoxy flexible adhesive. It is prepared by using a special bisphenol epoxy resin, flexible epoxy resin, toughening agent, filler, reactive diluent, latent curing agent, coupling agent, additives, and surfactant in a specific ratio. This results in a one-component epoxy flexible adhesive with excellent flexibility, effectively solving the problem of decreased flexibility in existing one-component epoxy flexible adhesives after high-temperature aging. It can reduce internal stress generated during curing or in high and low temperature environments, reducing damage to electronic components. Moreover, it can be cured at only medium and low temperatures, saving resources, reducing costs, and improving production efficiency, making it applicable to more fields. However, it does not address the issue of epoxy resin exudation.

[0005] CN1241807A discloses a dual-curing adhesive system. First, the adhesive is pre-cured by light radiation to limit resin precipitation. Then, the resin system is further cured by heating to increase the resin crosslinking density. This method can reduce resin precipitation to some extent, but it also increases equipment investment and process complexity.

[0006] Therefore, developing a single-component epoxy adhesive with low exudation, strong peel strength to substrates, and long-term storage capability has become an urgent problem to be solved in this field. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a one-component epoxy adhesive, its preparation method, and its application. By introducing leveling agents and fluorocarbon surfactants into the epoxy resin system, the problems of easy diffusion and precipitation existing in current commercially available epoxy adhesives are improved. Furthermore, this one-component epoxy adhesive also possesses excellent bonding performance, aging resistance, and reliability.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a one-component epoxy adhesive, wherein the one-component epoxy adhesive comprises, by weight, the following components: 35-45 parts of bisphenol type epoxy resin, 5-20 parts of polyurethane modified epoxy resin, 20-30 parts of curing agent, 0.1-1 parts of fluorocarbon surfactant and 0.1-1 parts of leveling agent.

[0010] Among them, 35-45 portions can be, for example, 35 portions, 36 portions, 38 portions, 40 portions, 42 portions, 44 portions, or 45 portions; 5-20 portions can be, for example, 5 portions, 6 portions, 8 portions, 10 portions, 12 portions, 14 portions, 15 portions, 16 portions, 18 portions, or 20 portions; 20-30 portions can be, for example, 20 portions, 22 portions, 24 portions, 25 portions, 26 portions, 28 portions, or 30 portions; 0.1-1 portion can be, for example, 0.1 portions, 0.2 portions, 0.4 portions, 0.5 portions, 0.6 portions, 0.8 portions, or 1 portion.

[0011] This invention adds fluorocarbon surfactants and silicone-based leveling agents to an epoxy resin system. The fluorocarbon surfactants, with their hydrophobic and oleophobic properties, form a barrier at the adhesive edges, preventing adhesive exudation. Combined with the leveling agent, the fluorocarbon surfactants are rapidly exuded to the outer edge of the adhesive. The combined effect of these two agents inhibits epoxy resin exudation. Furthermore, this invention adds polyurethane-modified epoxy resin, resulting in better flexibility and improved drop resistance after curing.

[0012] Preferably, the mass ratio of the fluorocarbon surfactant to the leveling agent is 1:(0.5-2), for example, it can be 1:0.5, 1:0.6, 1:0.8, 1:1, 1:1.2, 1:1.4, 1:1.5, 1:1.6, 1:1.8 or 1:2, etc.

[0013] The present invention specifies that the mass ratio of fluorocarbon leveling agent to silicone leveling agent is 1:(0.5-2). If too much fluorocarbon leveling agent is added, it will affect the adhesion of the adhesive. If too little fluorocarbon leveling agent is added, it will not have the effect of inhibiting precipitation.

[0014] Preferably, the leveling agent includes an organosilicon leveling agent.

[0015] Preferably, the fluorocarbon surfactant includes anionic fluorocarbon surfactants and / or nonionic fluorocarbon surfactants.

[0016] Preferably, the fluorocarbon surfactant includes any one or a combination of at least two of the following: FC-209, ZHY-09, ZHY-103 from Guangzhou Zhonghai Chemical Co., Ltd.; FSC-004, FSC-100, FC-403 from Morinaga & Co., Ltd.; FS-10 from Chemours Corporation; tridecylfluorooctane sulfonic acid; perfluorooctane sulfonic acid; or hexafluoropropylene oxide dimer acid.

[0017] Preferably, the bisphenol type epoxy resin includes bisphenol A type epoxy resin and / or bisphenol F type epoxy resin.

[0018] Preferably, the bisphenol A type epoxy resin has a viscosity of 8000-15000 cPs at 25°C, for example, it can be 8000 cPs, 9000 cPs, 10000 cPs, 11000 cPs, 12000 cPs, 13000 cPs, 14000 cPs or 15000 cPs, etc.

[0019] Preferably, the bisphenol F type epoxy resin has a viscosity of 2000-8000 cPs at 25°C, for example, it can be 2000 cPs, 3000 cPs, 4000 cPs, 5000 cPs, 6000 cPs, 7000 cPs or 8000 cPs.

[0020] Preferably, the curing agent comprises any one or a combination of at least two of the following: trimethylolpropane tris(3-mercaptopropionic acid), tris[2-(3-mercaptopropionic acid)ethyl]isocyanurate, pentaerythritol tetra(3-mercaptopropionic acid) ester, or diphenyl methylphosphonate.

[0021] The curing agent used in this invention, when mixed with the epoxy resin system, can maintain long-term stability. When used, the prepared single-component epoxy adhesive only needs to be exposed to heat, light, moisture and other conditions to cure into an adhesive.

[0022] Preferably, the single-component epoxy adhesive further comprises, by weight, any one or a combination of at least two of the following: 0.1-1 parts stabilizer, 1-3 parts thixotropic agent, 1-5 parts coupling agent, 5-10 parts toughening agent, 1-5 parts colorant, 1-5 parts accelerator, or 0.1-1 parts defoamer.

[0023] Among them, 0.1-1 portions can be, for example, 0.1 portions, 0.2 portions, 0.4 portions, 0.5 portions, 0.6 portions, 0.8 portions, or 1 portion; 1-3 portions can be, for example, 1 portion, 1.5 portions, 2 portions, 2.5 portions, or 3 portions; 5-10 portions can be, for example, 5 portions, 6 portions, 7 portions, 8 portions, 9 portions, or 10 portions; 1-5 portions can be, for example, 1 portion, 2 portions, 3 portions, 4 portions, or 5 portions.

[0024] Preferably, the stabilizer comprises any one or a combination of at least two of barbituric acid, salicylic acid, lactic acid, citric acid, benzoic acid, phenylacetic acid, barbituric acid, stearic acid, boric acid, or fumaric acid.

[0025] Preferably, the thixotropic agent comprises any one or a combination of two of silica, silicon dioxide, or organobentonite.

[0026] Preferably, the coupling agent comprises any one or a combination of at least two of 3-glycidyl etheroxypropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, titanate coupling agent or aluminate coupling agent.

[0027] Preferably, the toughening agent comprises an acrylonitrile-butadiene-styrene copolymer.

[0028] Preferably, the butadiene fragment in the acrylonitrile-butadiene-styrene copolymer accounts for 40-70% of the total mass percentage of the acrylonitrile-butadiene-styrene copolymer, for example, it can be 40%, 45%, 50%, 55%, 60%, 65% or 70%, etc.

[0029] Preferably, the pigment includes carbon black.

[0030] Preferably, the accelerator includes imidazole accelerators and / or modified amine accelerators.

[0031] Preferably, the defoamer includes an organosilicone defoamer.

[0032] In a second aspect, the present invention provides a method for preparing a one-component epoxy adhesive as described in the first aspect, the method comprising:

[0033] The components of the one-component epoxy adhesive are mixed in proportions by weight to obtain the one-component epoxy adhesive.

[0034] Preferably, the preparation method specifically includes:

[0035] (1) A mixture is prepared by mixing bisphenol epoxy resin, polyurethane modified epoxy resin, optionally toughening agent, optionally stabilizer, curing agent, optionally coupling agent, optionally colorant and optionally defoamer;

[0036] (2) The mixture obtained in step (1) is mixed with an optional thixotropic agent, an optional accelerator, a fluorocarbon surfactant and a leveling agent to obtain the single-component epoxy adhesive.

[0037] Preferably, the mixing temperature in step (1) is 75-80°C, for example, it can be 75°C, 76°C, 77°C, 78°C, 79°C or 80°C.

[0038] Preferably, the mixing time in step (1) is 50-70 min, for example, it can be 50 min, 55 min, 60 min, 65 min or 70 min.

[0039] Preferably, the mixing rate in step (1) is 900-1100 rpm, for example, it can be 900 rpm, 950 rpm, 1000 rpm, 1050 rpm or 1100 rpm.

[0040] Preferably, the mixing in step (2) is carried out under vacuum conditions.

[0041] Preferably, the vacuum degree of the vacuum condition is -0.05 to -0.15 MPa, for example, it can be -0.05 MPa, -0.08 MPa, -0.1 MPa, -0.12 MPa or -0.15 MPa.

[0042] Preferably, the mixing temperature in step (2) is 15-30℃, for example, it can be 15℃, 16℃, 18℃, 20℃, 22℃, 24℃, 26℃, 28℃ or 30℃, etc.

[0043] Preferably, the mixing time in step (2) is 3-6 hours, for example, it can be 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours or 6 hours.

[0044] Preferably, the mixing rate in step (2) is 500-800 rpm, for example, it can be 500 rpm, 600 rpm, 700 rpm or 800 rpm.

[0045] Thirdly, the present invention provides an application of a one-component epoxy adhesive as described in the first aspect in the bonding of a display screen.

[0046] The single-component epoxy adhesive provided by this invention only needs to be cured at 70-90℃ for 0.5-1h to form an adhesive.

[0047] Compared with the prior art, the present invention has at least the following beneficial effects:

[0048] (1) The single-component epoxy adhesive provided by the present invention improves the problems of easy diffusion and precipitation of epoxy adhesives on the market by introducing leveling agents and fluorocarbon surfactants into the epoxy resin system.

[0049] (2) The single-component epoxy adhesive provided by the present invention is easy to use, has a low curing temperature, is suitable for substrates that require low-temperature curing, has excellent bonding performance to a variety of materials, has high reliability after curing, and has excellent aging resistance.

[0050] (3) Specifically, the shear strength of the single-component epoxy adhesive provided by the present invention can reach 8.8-9.5 MPa, the shear strength after aging can reach 6.4-7.1 MPa, the shear strength after thermal shock can reach 8.3-9.4 MPa, and the precipitation diffusion is small with a precipitation distance of less than 0.25 mm. The adhesive film does not crack after the drop test. Attached Figure Description

[0051] Figure 1 This is a diagram showing the precipitation of the single-component epoxy adhesive provided in Embodiment 1 of the present invention after dispensing onto engineering plastics. Detailed Implementation

[0052] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0053] The specific information of the materials used in the following specific embodiments of the present invention is as follows:

[0054] (1) Bisphenol A type epoxy resin, YL980, purchased from Mitsubishi Chemical Corporation;

[0055] (2) Bisphenol F type epoxy resin, YL983U, purchased from Mitsubishi Chemical Corporation;

[0056] (3) Polyurethane modified epoxy resin, NEPR-133, purchased from Nan Ya Plastics Industry;

[0057] (4) Polyurethane modified epoxy resin, NEPR-133L, purchased from Nan Ya Plastics Industry;

[0058] (5) Polyurethane modified epoxy resin, EPU-253, purchased from Shanghai Luohe High-tech Materials;

[0059] (6) Toughening agent, ABS338, purchased from Lanxess Group;

[0060] (7) Toughening agent, Blendex 338, purchased from Galata;

[0061] (8) Toughening agent, INP338T, purchased from Sabic;

[0062] (9) Toughening agent, HR-181, purchased from Kumho, South Korea;

[0063] (10) Curing agent, pentaerythritol tetra(3-mercaptopropionic acid) ester, purchased from SC Organic Chemistry;

[0064] (11) Stabilizer, barbituric acid 1300, purchased from Shanghai Hesheng Chemical;

[0065] (12) Stabilizer, L07N, purchased from Shikoku Chemical;

[0066] (13) Thixotropic agent, silica TS-720, purchased from Cabot;

[0067] (14) Accelerator, imidazole accelerator PN-23, purchased from JICURE;

[0068] (15) Accelerator, imidazole accelerator PN-H, purchased from JICURE;

[0069] (16) Defoamer, silicone defoamer 6800, purchased from Deqian;

[0070] (17) Coupling agent, KBM-403, purchased from Shin-Etsu Chemical, Japan;

[0071] (18) Pigment, carbon black M800, purchased from Cabot;

[0072] (19) Nonionic fluorocarbon surfactant, FSC-004, purchased from Morinaga, Japan;

[0073] (20) Nonionic fluorocarbon surfactant, FSC-100, purchased from Morinaga, Japan;

[0074] (21) Anionic fluorocarbon surfactant, perfluorooctane sulfonic acid;

[0075] (22) Leveling agent, organosilicon leveling agent BYK-333, purchased from BYK Chemicals;

[0076] (23) Leveling agent, silicone leveling agent Synde-123, purchased from Zhuhai Xiande Materials;

[0077] (24) Leveling agent, organosilicon leveling agent BYK-3550, purchased from BYK Chemical.

[0078] Examples 1-7

[0079] Examples 1-7 provide a one-component epoxy adhesive and its preparation method, respectively. The components of the one-component epoxy adhesive are shown in Table 1 (the amounts of each component in Table 1 are parts by weight), where "--" indicates that the component was not added. The preparation method is as follows:

[0080] (1) Mix bisphenol epoxy resin, polyurethane modified epoxy resin, toughening agent, stabilizer, curing agent, coupling agent, color powder and defoamer, and stir at 75℃ and 1000rpm for 60min to obtain a mixture.

[0081] (2) Add thixotropic agent to the mixture obtained in step (1), stir for 2 hours, add accelerator and stir for 2 hours, and finally add fluorocarbon surfactant and leveling agent and stir for 2 hours to obtain the single-component epoxy adhesive. Step (2) is carried out in a vacuum of -0.1 MPa, 600 rpm and 25°C.

[0082] Table 1

[0083]

[0084]

[0085] Figure 1 This image shows the precipitation of the one-component epoxy adhesive provided in Embodiment 1 of the present invention after dispensing onto engineering plastics. As can be seen from the image, the one-component epoxy adhesive provided in Embodiment 1 of the present invention has clear edges after dispensing, a small precipitation distance, and does not migrate to the solder joints or near the lens.

[0086] Comparative Example 1

[0087] This comparative example provides a one-component epoxy adhesive and its preparation method.

[0088] The difference from Example 1 is that in this comparative example, the amount of EPU-133 added is 1 part.

[0089] Comparative Example 2

[0090] This comparative example provides a one-component epoxy adhesive and its preparation method.

[0091] The difference from Example 1 is that in this comparative example, the amount of EPU-133 added is 25 parts.

[0092] Comparative Example 3

[0093] This comparative example provides a one-component epoxy adhesive and its preparation method.

[0094] The difference from Example 1 is that, in this comparative example, the single-component epoxy adhesive does not contain fluorocarbon surfactants or silicone leveling agents.

[0095] Comparative Example 4

[0096] This comparative example provides a one-component epoxy adhesive and its preparation method.

[0097] The difference from Example 1 is that, in this comparative example, the single-component epoxy adhesive does not contain fluorocarbon surfactants, and the amount of silicone leveling agent added is 1 part.

[0098] Comparative Example 5

[0099] This comparative example provides a one-component epoxy adhesive and its preparation method.

[0100] The difference from Example 1 is that, in this comparative example, the single-component epoxy adhesive does not contain silicone leveling agents, and the amount of fluorocarbon surfactant added is 1 part.

[0101] Test methods

[0102] (1) Extrusion distance (mm): The one-component epoxy adhesives provided in Examples 1-7 and Comparative Examples 1-5 were applied to plasma-coated engineering plastics (LCP) with a droplet diameter of 1 mm. The adhesive was allowed to stand at 25°C for 1 hour, then placed in an oven for heat curing at 80°C for 1 hour. The extruded portion of the adhesive was then observed under a microscope (100x magnification), and the distance of the wetted edge of the adhesive was measured. Figure 1 As shown.

[0103] (2) Mechanical strength

[0104] Sample preparation and performance testing:

[0105] S1. Draw a straight line 5 mm away from one end of the substrate to be tested (LCP) as the boundary of the adhesive coating area;

[0106] S2. Apply 0.1g of the one-component epoxy adhesive provided in Examples 1-7 and Comparative Examples 1-5 evenly to the area between one end of the substrate to be tested and the straight line;

[0107] S3. Place another test material (glass) on a substrate coated with one end of a single-component epoxy adhesive. Place two copper wires with a diameter of 30μm parallel between the two and squeeze the single-component epoxy adhesive into a thin adhesive layer. The adhesive layer should not have gaps or air bubbles. Try to control the overflow of adhesive to obtain an adhesive film with a thickness of 30μm.

[0108] S4. Place the overlapped workpieces into an oven at 80°C for 30 minutes to cure.

[0109] S5. After placing the cured workpiece at 25℃ for 15 minutes, put it into a universal tensile testing machine to test the tensile value and calculate the shear strength according to the following formula;

[0110] Shear strength (MPa) = Average tensile force (N) / Bond area (mm²) 2 ).

[0111] Aging test: Place the cured sample from step S5 into an aging chamber for a double 85 test (85°C and 85% humidity). After 500 hours, take it out and test the shear strength between the glass and LPC.

[0112] Thermal shock test: The sample cured in step S5 was subjected to thermal shock (first placed in a high temperature environment of 85℃ for 0.5h, and then immediately placed in a -40℃ environment for 0.5h, which is one cycle). After 500 cycles, the shear strength between the glass and LPC was tested.

[0113] Drop test: Place the cured sample from step S5 into a roller drop tester, drop it from a height of 1000mm, drop it at a speed of 20 drops / min, drop it 500 times, and observe whether there is any cracking at the bonding interface.

[0114] Test Results

[0115] The performance of the one-component epoxy adhesives provided in Examples 1-7 and Comparative Examples 1-5 was tested, and the results are shown in Table 2 below:

[0116] Table 2

[0117]

[0118]

[0119] The test results show that:

[0120] (1) As can be seen from Examples 1 to 7, the single-component epoxy adhesive provided by the present invention improves the problems of easy diffusion and precipitation existing in the current adhesives on the market by introducing leveling agents and fluorocarbon surfactants into the epoxy resin system. Moreover, the single-component epoxy adhesive also has excellent bonding performance, aging resistance and reliability. Specifically, the shear strength of the single-component epoxy adhesive provided by the present invention can reach 8.8-9.5 MPa, the shear strength after aging can reach 6.4-7.1 MPa, and the shear strength after thermal shock can reach 8.3-9.4 MPa. At the same time, the precipitation and diffusion are minimal, the precipitation distance is less than 0.25 mm, and the adhesive film does not crack after the drop test.

[0121] (2) As can be seen from Examples 1 to 6-7, the present invention can achieve better anti-exudation and bonding performance by further limiting the mass ratio of fluorocarbon surfactant and leveling agent.

[0122] (3) As can be seen from Example 1 and Comparative Examples 1-2, the present invention can achieve excellent drop resistance and aging resistance by adding polyurethane modified epoxy resin to the epoxy resin system. However, when too little polyurethane modified epoxy resin is added, the adhesive film cracks after the drop test, and the reliability of the adhesive film is poor. When too much polyurethane modified epoxy resin is added, the overall crosslinking density of the adhesive decreases due to the introduction of too many polyurethane flexible segments, making it easier for oxygen and moisture to penetrate, resulting in a significant decrease in aging resistance.

[0123] (3) As can be seen from Example 1 and Comparative Examples 3-5, the present invention improves the precipitation problem of single-component epoxy adhesives by introducing organosilicon leveling agents and fluorocarbon surfactants into the epoxy resin system, and improves the adhesion, reliability and aging resistance of single-component epoxy adhesives. However, when any component is not used or is missing, it cannot achieve the technical effect of improving the precipitation problem.

[0124] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A one-component epoxy adhesive, characterized in that, The single-component epoxy adhesive comprises the following components by weight: 35-45 parts of bisphenol-type epoxy resin, 5-20 parts of polyurethane-modified epoxy resin, 20-30 parts of curing agent, 0.1-1 parts of fluorocarbon surfactant, and 0.1-1 parts of leveling agent.

2. The one-component epoxy adhesive according to claim 1, characterized in that, The mass ratio of the fluorocarbon surfactant to the leveling agent is 1:(0.5-2); Preferably, the leveling agent includes an organosilicon leveling agent; Preferably, the fluorocarbon surfactant includes anionic fluorocarbon surfactants and / or nonionic fluorocarbon surfactants.

3. The one-component epoxy adhesive according to claim 1 or 2, characterized in that, The bisphenol type epoxy resin includes bisphenol A type epoxy resin and / or bisphenol F type epoxy resin; Preferably, the bisphenol A type epoxy resin has a viscosity of 8000-15000 cPs at 25°C; Preferably, the bisphenol F epoxy resin has a viscosity of 2000-8000 cPs at 25°C.

4. The one-component epoxy adhesive according to any one of claims 1-3, characterized in that, The curing agent includes any one or a combination of at least two of the following: trimethylolpropane tris(3-mercaptopropionic acid), tris[2-(3-mercaptopropionic acid)ethyl]isocyanurate, pentaerythritol tetra(3-mercaptopropionic acid) ester, or diphenyl methylphosphonate.

5. The one-component epoxy adhesive according to any one of claims 1-4, characterized in that, The single-component epoxy adhesive further includes, by weight, any one or a combination of at least two of the following: 0.1-1 parts stabilizer, 1-3 parts thixotropic agent, 1-5 parts coupling agent, 5-10 parts toughening agent, 1-5 parts colorant, 1-5 parts accelerator, or 0.1-1 parts defoamer.

6. The one-component epoxy adhesive according to claim 5, characterized in that, The stabilizer includes any one or a combination of at least two of barbituric acid, salicylic acid, lactic acid, citric acid, benzoic acid, phenylacetic acid, barbituric acid, stearic acid, boric acid, or fumaric acid. Preferably, the thixotropic agent comprises any one or a combination of two of silica, silicon dioxide, or organobentonite; Preferably, the coupling agent comprises any one or a combination of at least two of 3-glycidyl etheroxypropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, titanate coupling agent or aluminate coupling agent; Preferably, the toughening agent comprises an acrylonitrile-butadiene-styrene copolymer; Preferably, the butadiene fragment in the acrylonitrile-butadiene-styrene copolymer accounts for 40-70% of the total mass percentage of the acrylonitrile-butadiene-styrene copolymer; Preferably, the pigment includes carbon black; Preferably, the accelerator includes imidazole accelerators and / or modified amine accelerators; Preferably, the defoamer includes an organosilicone defoamer.

7. A method for preparing a one-component epoxy adhesive as described in any one of claims 1-6, characterized in that, The preparation method includes: The components of the one-component epoxy adhesive are mixed in proportions by weight to obtain the one-component epoxy adhesive.

8. The method for preparing the one-component epoxy adhesive according to claim 7, characterized in that, The preparation method specifically includes: (1) A mixture is prepared by mixing bisphenol epoxy resin, polyurethane modified epoxy resin, optionally toughening agent, optionally stabilizer, curing agent, optionally coupling agent, optionally colorant and optionally defoamer; (2) The mixture obtained in step (1) is mixed with an optional thixotropic agent, an optional accelerator, a fluorocarbon surfactant and a leveling agent to obtain the single-component epoxy adhesive.

9. The method for preparing the one-component epoxy adhesive according to claim 8, characterized in that, The mixing temperature in step (1) is 75-80℃; Preferably, the mixing time in step (1) is 50-70 min; Preferably, the mixing rate in step (1) is 900-1100 rpm; Preferably, the mixing in step (2) is carried out under vacuum conditions; Preferably, the vacuum degree of the vacuum condition is -0.05 to -0.15 MPa; Preferably, the mixing temperature in step (2) is 15-30°C; Preferably, the mixing time in step (2) is 3-6 hours; Preferably, the mixing rate in step (2) is 500-800 rpm.

10. The application of a one-component epoxy adhesive as described in any one of claims 1-6 in the bonding of a display screen.

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