SCF component buffer adhesive film and preparation method thereof

Abstract

The present application relates to the technical field of acrylic adhesive, in particular to a SCF assembly buffer adhesive film and a preparation method thereof.The present application comprises an acrylic buffer layer and a bonding force improvement layer prepared from two modified acrylic resins, wherein the acrylic buffer layer comprises solvent, methyl acrylate, isooctyl acrylate, butyl acrylate, hydroxyethyl acrylate, azobisdimethylvaleronitrile, alpha-methyl styrene dimer, ethylene glycol dimethacrylate and 2,2-dimethoxybutane; the bonding force improvement layer comprises solvent, isooctyl acrylate, hydroxybutyl acrylate, glycidyl methacrylate, N-(isobutoxy) methacrylamide and azobisdimethylvaleronitrile; the pure adhesive film structure used in the present application can achieve the premise of the foam cushioning performance, has superior flatness, solves the poor adhesion of the foam due to the foaming process factors, and solves the poor orange peel of the display appearance.

Description

Technical Field

[0001] This invention relates to the field of acrylic adhesive technology, specifically to an SCF component buffer film and its preparation method. Background Technology

[0002] SCF (Solar Fiber Foam) components are a general term for composite structures of copper foil foam and mesh adhesive layers, which serve to cushion, dissipate heat, and provide protection and support. The foam used for the cushioning layer is mostly less than 0.16mm thick, and has high requirements for thickness uniformity and surface flatness. According to the manufacturing process of the foam, it can be roughly divided into three categories: physical foaming process, filler foaming process, and chemical foaming process. The above foaming process paths can solve the needs of application cushioning.

[0003] For example, Chinese Patent Publication No. CN222274445U discloses a multi-layered buffer tape for SCF screens, comprising a PI layer, a first silicone layer disposed on the upper surface of the PI layer, a second silicone layer disposed on the lower surface of the PI layer, a copper foil layer disposed on the upper surface of the first silicone layer, and a release film disposed on the lower surface of the second silicone layer. It effectively prevents edge curling; the copper foil not only resists impact and dissipates heat, but also effectively prevents edge curling due to its own hardness.

[0004] However, due to the inherent manufacturing process of foamed cotton, its foaming structure is randomly distributed and the size of the foamed spheres is not uniform. This characteristic results in a rough, uneven surface on the foamed cotton. Poor flatness can affect the appearance of the OLED module display, causing water ripple marks. In severe cases, it can lead to orange peel defects in the display evaluation, resulting in screen failure.

[0005] To address the above problems, this invention provides an SCF component buffer film and its preparation method. Summary of the Invention

[0006] The purpose of this invention is to provide a cushioning film for SCF components and its preparation method. The pure film structure can achieve the cushioning performance of foam while possessing excellent flatness, thus solving the problems of poor adhesion and orange peel appearance caused by the foam's own foaming process.

[0007] This invention provides the following technical solution:

[0008] An SCF component buffer film includes an acrylic buffer layer made of two modified acrylic resins and an adhesion-improving layer, wherein the acrylic buffer layer comprises the following substances in parts by weight:

[0009] 4-6 parts methyl acrylate, 40-60 parts isooctyl acrylate, 7-8 parts butyl acrylate, 0.5-1 part hydroxyethyl acrylate, 0.4-0.8 parts ethylene glycol dimethacrylate, 0.7-1.2 parts 2,2-dimethoxybutane, 0.1-0.3 parts azobisisobutyronitrile, 0.2-0.3 parts α-methylstyrene dimer, and 30-40 parts solvent;

[0010] The bonding strength improvement layer comprises the following substances in parts by weight:

[0011] 10-15 parts isooctyl acrylate, 3-5 parts glycidyl methacrylate, 3-5 parts N-(isobutoxy)methacrylamide, 5-8 parts hydroxybutyl acrylate, 0.1-0.3 parts azobisisobutyronitrile, and 10-15 parts solvent.

[0012] Ideally, the solvent is any two or a combination of three of the following: ethyl acetate, methanol, ethylcyclohexane, n-butanol, and 2-butanone.

[0013] In a more optimized manner, the modified acrylic adhesive used to synthesize the acrylic buffer layer includes the following steps:

[0014] Step 1: Add a measured amount of solvent, methyl acrylate and isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere, control the temperature at 65-70℃ and slowly add a mixed liquid containing butyl acrylate, hydroxyethyl acrylate and azobisisobutyl cyanide. The addition time is 3-4 hours, and the temperature is maintained for 4-6 hours after the addition is completed.

[0015] Step 2: Lower the temperature to 40-45℃, slowly add 0.2-0.3 parts of α-methylstyrene dimer, and finish the addition within 1 hour. After maintaining the temperature for 2 hours, add a mixed liquid containing 0.4-0.8 parts of ethylene glycol dimethacrylate, 0.7-1.2 parts of 2,2-dimethoxybutane, and 0-10 parts of solvent, with a adding time of 1-2 hours.

[0016] After the addition is complete, the temperature is lowered to room temperature to obtain the modified acrylic adhesive.

[0017] In a more optimized manner, the acrylic adhesive used to synthesize the bonding strength improvement layer includes the following steps:

[0018] Add a measured amount of solvent, isooctyl acrylate and hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection, control the temperature at 75-80℃ and slowly add a mixed solution containing glycidyl methacrylate, N-(isobutoxy)methacrylamide and azobisisobutyronitrile over a period of 1-2 hours.

[0019] After the dripping is complete, the temperature will be controlled for 2-3 hours until it reaches room temperature to obtain the improved acrylic adhesive layer.

[0020] The present invention also provides a method for preparing an SCF module buffer film, for preparing any of the above-mentioned SCF module buffer films, comprising the following steps:

[0021] S1: Preparation of modified acrylic adhesive;

[0022] S2: Preparation of acrylic adhesive for the improvement layer;

[0023] S3: Take the modified acrylic adhesive synthesized in S1, mix it with isocyanate curing agent, stir it in a mixing tank at 300-400r / min for 15min, and then apply the acrylic buffer layer.

[0024] S4: Take the improved acrylic adhesive synthesized in S2, add solvent to reduce solid content and viscosity, and mix with isocyanate curing agent. After mixing in a mixing tank at 200-300r / min for 15min, apply the bonding improvement layer to obtain the finished SCF component buffer film.

[0025] Ideally, the isocyanate curing agent used in step S3 is an aliphatic isocyanate.

[0026] More optimally, the aliphatic isocyanate is hexamethylene diisocyanate, and its addition amount is 0.5% by weight.

[0027] Ideally, the isocyanate curing agent used in step S4 is an aromatic isocyanate.

[0028] More preferably, the aromatic isocyanate is toluene diisocyanate (TDI, L75), and its addition amount is 1% by weight.

[0029] In a more optimized manner, the adhesion improvement layer is uniformly coated on both sides of the acrylic buffer layer, wherein the thickness of the acrylic buffer layer is 90-95μm, and the thickness of the adhesion improvement layer is 4-5% of the thickness of the acrylic buffer layer.

[0030] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0031] (1) In this invention, a self-synthesized modified acrylic buffer film is coated with 0.5% hexamethylene diisocyanate curing agent to form a film with a thickness of 90-95μm; the material has superior surface smoothness and buffering properties compared with the buffer foam.

[0032] (2) In this invention, a self-synthesized bonding strength improvement layer is combined with 1% isocyanate curing agent, and the coating thickness is 4-5% of the buffer layer thickness; the bonding strength improvement layer and the buffer layer do not separate under different aging conditions, and have excellent adhesion performance to backing materials such as mesh adhesive and other low-surface materials. Attached Figure Description

[0033] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0034] Figure 1 This is a structural diagram of the SCF buffer film;

[0035] Figure 2 The graph shows a comparison of the flatness of the buffer films prepared in each embodiment and the comparative example.

[0036] Figure 3 The rheological spectrum of the acrylic buffer layer;

[0037] Figure 4 Rheological test spectrum of the bonding strength improvement layer.

[0038] Among them, 101 is the bonding strength improvement layer; 102 is the acrylic buffer layer. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] The present invention verifies the properties of the SCF component buffer film obtained through several different embodiments and comparative examples.

[0041] Example 1

[0042] S1: The synthesis method of the acrylic buffer layer is as follows:

[0043] Add 30 parts solvent, 4 parts methyl acrylate, and 40 parts isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere and controlled temperature of 65°C, slowly add a mixed liquid containing 7 parts butyl acrylate, 0.5 parts hydroxyethyl acrylate, and 0.1 parts azobisisobutyronitrile (AIBN) over a period of 3 hours. After the addition is complete, maintain the temperature for 4 hours. Then, lower the temperature to 40°C and slowly add 0.2 parts α-methylstyrene dimer over a period of 1 hour. After the addition is complete, maintain the temperature for 2 hours. Then, add 0.4 parts ethylene glycol dimethacrylate and 0.7 parts 2,2-dimethoxybutane over a period of 1 hour. After the addition is complete, cool to room temperature to obtain the modified acrylic adhesive.

[0044] S2: The synthesis method of the bonding strength improvement layer is as follows:

[0045] Add 10 parts solvent, 10 parts isooctyl acrylate, and 5 parts hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection and temperature control at 75°C, slowly add a mixed solution containing 3 parts glycidyl methacrylate, 3 parts N-(isobutoxy)methacrylamide, and 0.1 parts azobisisobutyronitrile. The addition time is 1 hour. After the addition is completed, control the temperature for 2 hours to bring it down to room temperature to obtain the improved acrylic adhesive.

[0046] S3: Take the modified acrylic buffer adhesive synthesized in S1, mix it with 0.5% hexamethylene diisocyanate curing agent, stir it evenly and then apply the buffer layer with a thickness of 90μm.

[0047] S4: Take the resin of the bonding improvement layer synthesized in S2 and mix it with 1% isocyanate curing agent. After mixing and stirring for 15 minutes, the bonding improvement layer can be coated. The thickness of the bonding improvement layer and the thickness of the buffer layer account for 5%.

[0048] Example 2

[0049] S1: The synthesis method of the acrylic buffer layer is as follows:

[0050] Add 40 parts solvent, 6 parts methyl acrylate, and 60 parts isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere and at a controlled temperature of 70°C, slowly add a mixed liquid containing 8 parts butyl acrylate, 1 part hydroxyethyl acrylate, and 0.3 parts azobisisobutyronitrile (AIBN) over 4 hours. After the addition is complete, maintain the temperature for 6 hours. Then, lower the temperature to 45°C and slowly add 0.3 parts α-methylstyrene dimer over 1 hour. After the addition is complete, maintain the temperature for 2 hours. Then, add 0.8 parts ethylene glycol dimethacrylate and 1.2 parts 2,2-dimethoxybutane over 2 hours. After the addition is complete, cool to room temperature to obtain the modified acrylic adhesive.

[0051] S2: The synthesis method of the bonding strength improvement layer is as follows:

[0052] Add 15 parts solvent, 15 parts isooctyl acrylate, and 8 parts hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection and temperature control at 80°C, slowly add a mixed solution containing 5 parts glycidyl methacrylate, 5 parts N-(isobutoxy)methacrylamide, and 0.3 parts azobisisobutyronitrile. The addition time is 2 hours. After the addition is completed, control the temperature for 3 hours to bring it down to room temperature to obtain the improved acrylic adhesive.

[0053] S3: Take the modified acrylic buffer adhesive synthesized in S1, mix it with 0.5% hexamethylene diisocyanate curing agent, stir it evenly and then apply the buffer layer with a thickness of 95μm.

[0054] S4: Take the resin of the bonding improvement layer synthesized in S2 and mix it with 1% isocyanate curing agent. After mixing and stirring for 15 minutes, the bonding improvement layer can be coated. The thickness of the bonding improvement layer and the thickness of the buffer layer account for 5%.

[0055] Example 3

[0056] S1: The synthesis method of the acrylic buffer layer is as follows:

[0057] Add 35 parts solvent, 5 parts methyl acrylate, and 50 parts isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere and controlled temperature of 68°C, slowly add a mixed liquid containing 7.5 parts butyl acrylate, 0.8 parts hydroxyethyl acrylate, and 0.2 parts azobisisobutyronitrile (AIBN) over 4 hours. After the addition is complete, maintain the temperature for 5 hours. Then, lower the temperature to 42°C and slowly add 0.25 parts α-methylstyrene dimer over 1 hour. After the addition is complete, maintain the temperature for 2 hours. Then, add 0.6 parts ethylene glycol dimethacrylate and 1 part 2,2-dimethoxybutane over 2 hours. After the addition is complete, cool to room temperature to obtain the modified acrylic adhesive.

[0058] S2: The synthesis method of the bonding strength improvement layer is as follows:

[0059] Add 15 parts solvent, 13 parts isooctyl acrylate, and 7.5 parts hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection and temperature control at 78°C, slowly add a mixed solution containing 4 parts glycidyl methacrylate, 4 parts N-(isobutoxy)methacrylamide, and 0.2 parts azobisisobutyl cyanide. The addition time is 2 hours. After the addition is completed, control the temperature for 2 hours to bring it down to room temperature to obtain the improved acrylic adhesive.

[0060] S3: Take the modified acrylic buffer adhesive synthesized in S1, mix it with 0.5% hexamethylene diisocyanate curing agent, stir it evenly and then apply the buffer layer with a thickness of 90μm.

[0061] S4: Take the resin of the bonding improvement layer synthesized in S2 and mix it with 1% isocyanate curing agent. After mixing and stirring for 15 minutes, the bonding improvement layer can be coated. The thickness of the bonding improvement layer and the thickness of the buffer layer account for 4%.

[0062] Comparative Example 1

[0063] S1: The synthesis method of the modified acrylic buffer layer is as follows:

[0064] Add 30 parts solvent, 4 parts methyl acrylate, and 40 parts isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere and controlled temperature of 65°C, slowly add a mixed liquid containing 7 parts butyl acrylate, 0.5 parts hydroxyethyl acrylate, and 0.1 parts azobisisobutyronitrile (AIBN) over a period of 3 hours. After the addition is complete, maintain the temperature for 4 hours. Then, lower the temperature to 40°C and slowly add 0.2 parts α-methylstyrene dimer over a period of 1 hour. After the addition is complete, maintain the temperature for 2 hours. Then, add 0.4 parts ethylene glycol dimethacrylate and 0.7 parts 2,2-dimethoxybutane over a period of 1 hour. After the addition is complete, cool to room temperature to obtain the modified acrylic adhesive.

[0065] S2: The synthesis method of the bonding strength improvement layer is as follows:

[0066] Add 10 parts solvent, 10 parts isooctyl acrylate, and 5 parts hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection and temperature control at 75°C, slowly add a mixed solution containing 3 parts glycidyl methacrylate, 3 parts N-(isobutoxy)methacrylamide, and 0.1 parts azobisisobutyronitrile. The addition time is 1 hour. After the addition is completed, control the temperature for 2 hours to bring it down to room temperature to obtain the improved acrylic adhesive.

[0067] S3: Take the modified acrylic buffer adhesive synthesized in S1, mix it with 0.5% hexamethylene diisocyanate curing agent, stir it evenly and then apply the buffer layer with a thickness of 90μm.

[0068] S4: Take the resin of the bonding improvement layer synthesized in S2 and mix it with 1% isocyanate curing agent. After mixing and stirring for 15 minutes, the bonding improvement layer can be coated. The thickness of the bonding improvement layer and the thickness of the buffer layer are greater than 5%.

[0069] Comparative Example 2

[0070] S1: The synthesis method of the modified acrylic buffer layer is as follows:

[0071] Add 30 parts solvent, 4 parts methyl acrylate, and 40 parts isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere and controlled temperature of 65°C, slowly add a mixed liquid containing 7 parts butyl acrylate, 0.5 parts hydroxyethyl acrylate, and 0.1 parts azobisisobutyronitrile (AIBN) over a period of 3 hours. After the addition is complete, maintain the temperature for 4 hours. Then, lower the temperature to 40°C and slowly add 0.2 parts α-methylstyrene dimer over a period of 1 hour. After the addition is complete, maintain the temperature for 2 hours. Then, add 0.4 parts ethylene glycol dimethacrylate and 0.7 parts 2,2-dimethoxybutane over a period of 1 hour. After the addition is complete, cool to room temperature to obtain the modified acrylic adhesive.

[0072] S2: The synthesis method of the bonding strength improvement layer is as follows:

[0073] Add 10 parts solvent, 10 parts isooctyl acrylate, and 5 parts hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection and temperature control at 75°C, slowly add a mixed solution containing 3 parts glycidyl methacrylate, 3 parts N-(isobutoxy)methacrylamide, and 0.1 parts azobisisobutyronitrile. The addition time is 1 hour. After the addition is completed, control the temperature for 2 hours to bring it down to room temperature to obtain the improved acrylic adhesive.

[0074] S3: Take the modified acrylic buffer adhesive synthesized in S1, mix it with 0.5% hexamethylene diisocyanate curing agent, stir it evenly and then apply the buffer layer with a thickness of 90μm.

[0075] S4: Take the resin of the bonding improvement layer synthesized in S2 and mix it with 1% isocyanate curing agent. After mixing and stirring for 15 minutes, the bonding improvement layer can be coated. The thickness of the bonding improvement layer and the thickness of the buffer layer are less than 4%.

[0076] Comparative Example 3

[0077] S1: The synthesis method of the modified acrylic buffer layer is as follows:

[0078] Add 30 parts solvent, 4 parts methyl acrylate, and 40 parts isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere and controlled temperature of 65°C, slowly add a mixed liquid containing 7 parts butyl acrylate, 0.5 parts hydroxyethyl acrylate, and 0.1 parts azobisisobutyronitrile (AIBN) over a period of 3 hours. After the addition is complete, maintain the temperature for 4 hours. Then, lower the temperature to 40°C and slowly add 0.2 parts α-methylstyrene dimer over a period of 1 hour. After the addition is complete, maintain the temperature for 2 hours. Then, add 0.4 parts ethylene glycol dimethacrylate and 0.7 parts 2,2-dimethoxybutane over a period of 1 hour. After the addition is complete, cool to room temperature to obtain the modified acrylic adhesive.

[0079] S2: Take the modified acrylic buffer adhesive synthesized in S1, add 0.5% hexamethylene diisocyanate curing agent, mix and stir evenly, and then apply the buffer film; pure film coating with a thickness of 100μm, without an adhesion improvement layer.

[0080] Comparative Example 4

[0081] S1: The synthesis method of the modified acrylic buffer layer is as follows:

[0082] Add 30 parts solvent, 4 parts methyl acrylate, and 40 parts isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere and a controlled temperature of 65°C, slowly add a mixed liquid containing 7 parts butyl acrylate, 0.5 parts hydroxyethyl acrylate, and 0.1 parts azobisisobutyl cyanide over a period of 3 hours. After the addition is complete, maintain the temperature for 4 hours and then cool to room temperature to obtain the modified acrylic adhesive.

[0083] S2: The synthesis method of the bonding strength improvement layer is as follows:

[0084] Add 10 parts solvent, 10 parts isooctyl acrylate, and 5 parts hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection and temperature control at 75°C, slowly add a mixed solution containing 3 parts glycidyl methacrylate, 3 parts N-(isobutoxy)methacrylamide, and 0.1 parts azobisisobutyronitrile. The addition time is 1 hour. After the addition is completed, control the temperature for 2 hours to bring it down to room temperature to obtain the improved acrylic adhesive.

[0085] S3: Take the modified acrylic buffer adhesive synthesized in S1, mix it with 0.5% hexamethylene diisocyanate curing agent, stir it evenly and then apply the buffer layer with a thickness of 90μm.

[0086] S4: Take the resin of the bonding improvement layer synthesized in S2 and mix it with 1% isocyanate curing agent. After mixing and stirring for 15 minutes, the bonding improvement layer can be coated. The thickness of the bonding improvement layer and the thickness of the buffer layer account for 5%.

[0087] Comparative Example 5

[0088] S1: The synthesis method of the modified acrylic buffer layer is as follows:

[0089] Add 30 parts solvent, 4 parts methyl acrylate, and 60 parts isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere and controlled temperature of 65°C, slowly add a mixed liquid containing 10 parts butyl acrylate, 1 part hydroxyethyl acrylate, and 0.2 parts azobisisobutyronitrile (AIBN) over 3 hours. After the addition is complete, maintain the temperature for 4 hours. Lower the temperature to 40°C and slowly add 0.5 parts α-methylstyrene dimer over 1 hour. After the addition is complete, maintain the temperature for 2 hours. Then add 0.5 parts ethylene glycol dimethacrylate and 1.5 parts 2,2-dimethoxybutane over 1 hour. After the addition is complete, cool to room temperature to obtain the modified acrylic adhesive.

[0090] S2: The synthesis method of the bonding strength improvement layer is as follows:

[0091] Add 10 parts solvent, 10 parts isooctyl acrylate, and 5 parts hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection and temperature control at 75°C, slowly add a mixed solution containing 3 parts glycidyl methacrylate, 3 parts N-(isobutoxy)methacrylamide, and 0.1 parts azobisisobutyronitrile. The addition time is 1 hour. After the addition is completed, control the temperature for 2 hours to bring it down to room temperature to obtain the improved acrylic adhesive.

[0092] S3: Take the modified acrylic buffer adhesive synthesized in S1, mix it with 0.5% hexamethylene diisocyanate curing agent, stir it evenly and then apply the buffer layer with a thickness of 90μm.

[0093] S4: Take the resin of the bonding improvement layer synthesized in S2 and mix it with 1% isocyanate curing agent. After mixing and stirring for 15 minutes, the bonding improvement layer can be coated. The thickness of the bonding improvement layer and the thickness of the buffer layer account for 5%.

[0094] After the samples were prepared according to the above embodiments and comparative examples, the bonding strength and flatness of the die-cut parts were tested.

[0095] Adhesion strength test: The test shall be conducted in accordance with the standard "Test method for peel strength of adhesive tape" (GB / T2792-2014).

[0096] Flatness Test: One side of the buffer film (including the adhesion improvement layer) is laminated with the adhesive side of the copper foil single-sided pressure-sensitive adhesive, and the other side is laminated with the non-mesh side of the ultra-fine mesh adhesive to form an SCF composite module. A flatness test module sample is formed by laminating the mesh side of the ultra-fine mesh adhesive with 100μm transparent PET. A rectangular test light source is selected, and under 1100 lux illumination, the reflected image of the light source on the PET surface is observed from a distance of 50–60 cm.

[0097] Impact Test: The ultra-fine mesh adhesive in the SCF component is laminated with pressure-sensitive paper (Fuji, MS series pressure-sensitive paper) to form an impact simulation test module. A 2g stainless steel ball is dropped naturally from a height of 100mm onto the copper foil pressure-sensitive adhesive side to impact the impact simulation test module. The pressure-sensitive paper will change color differently due to the difference in impact intensity. A special adapter is then used to identify the difference in color change of the pressure-sensitive adhesive and read the impact intensity in MPa.

[0098] The comparison sample used was Anyone integrated foam adhesive from South Korea with a thickness of 100μm.

[0099] The copper foil single-sided adhesive used in the bonding strength test was Nissin 30μm single-sided adhesive, and the mesh adhesive was Anyone ultra-fine mesh adhesive.

[0100] The test results are shown in Table 1 and Figure 2 As shown.

[0101] Table 1. Test results of the buffer films prepared in each embodiment and comparative example.

[0102]

[0103]

[0104] Compare Table 1 with Figure 2 Combining these, we can conclude that:

[0105] The buffer films prepared in Examples 1-3 and Comparative Examples 1-5 have superior edge smoothing properties compared to foam, which will reduce the risk of orange peel texture and wrinkles in SCF modules caused by uneven foaming during actual use.

[0106] The buffer film layer and the bonding improvement layer prepared in Examples 1-3 have point impact performance and non-mesh surface adhesive performance relative to copper foil single-sided adhesive and Embo mesh adhesive compared to foam.

[0107] Comparative Example 1 shows that increasing the bonding strength improves the thickness of the layer, which in turn improves the bonding strength, but has the opposite effect on the point impact performance.

[0108] Comparative Example 2 reduces the bonding strength and improves the layer thickness, has no effect on point impact, but has the opposite effect on the bonding strength;

[0109] Comparative Example 3 uses a pure buffer film to prepare SCF components. While ensuring point impact performance, the bonding strength of the buffer film layer is lower than that of the copper foil single-sided adhesive and Embo adhesive than that of the foam. This highlights the necessity of the buffer layer + bonding strength improvement layer in this patent application.

[0110] Comparative Examples 4-5, under the premise that the bonding strength improvement layer formula and thickness remain unchanged, changing the buffer layer formula has a counteracting effect on point impacts on the overall structure, demonstrating the importance of protecting the buffer layer formula of this invention patent.

[0111] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0112] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A buffer film for SCF components, characterized in that: It includes an acrylic buffer layer and an adhesion-improving layer made from two modified acrylic resins, wherein the acrylic buffer layer comprises the following substances by weight: 4-6 parts methyl acrylate, 40-60 parts isooctyl acrylate, 7-8 parts butyl acrylate, 0.5-1 part hydroxyethyl acrylate, 0.4-0.8 parts ethylene glycol dimethacrylate, 0.7-1.2 parts 2,2-dimethoxybutane, 0.1-0.3 parts azobisisobutyronitrile, 0.2-0.3 parts α-methylstyrene dimer, and 30-40 parts solvent; The bonding strength improvement layer comprises the following substances in parts by weight: 10-15 parts isooctyl acrylate, 3-5 parts glycidyl methacrylate, 3-5 parts N-(isobutoxy)methacrylamide, 5-8 parts hydroxybutyl acrylate, 0.1-0.3 parts azobisisobutyronitrile, and 10-15 parts solvent.

2. The SCF component buffer film according to claim 1, characterized in that: The solvent is any two or a combination of three of the following: ethyl acetate, methanol, ethylcyclohexane, n-butanol, and 2-butanone.

3. The SCF component buffer film according to claim 1, characterized in that, The modified acrylic adhesive used to synthesize the acrylic buffer layer includes the following steps: Step 1: Add a measured amount of solvent, methyl acrylate and isooctyl acrylate to a three-necked flask. Under a nitrogen atmosphere, control the temperature at 65-70℃ and slowly add a mixed liquid containing butyl acrylate, hydroxyethyl acrylate and azobisisobutyl cyanide. The addition time is 3-4 hours, and the temperature is maintained for 4-6 hours after the addition is completed. Step 2: Lower the temperature to 40-45℃, slowly add 0.2-0.3 parts of α-methylstyrene dimer, and finish the addition within 1 hour. After maintaining the temperature for 2 hours, add a mixed liquid containing 0.4-0.8 parts of ethylene glycol dimethacrylate, 0.7-1.2 parts of 2,2-dimethoxybutane, and 0-10 parts of solvent, with a adding time of 1-2 hours. After the addition is complete, the temperature is lowered to room temperature to obtain the modified acrylic adhesive.

4. The SCF component buffer film according to claim 1, characterized in that, The acrylic adhesive used to synthesize the bonding strength improvement layer includes the following steps: Add a measured amount of solvent, isooctyl acrylate and hydroxybutyl acrylate to a three-necked flask. Under nitrogen protection, control the temperature at 75-80℃ and slowly add a mixed solution containing glycidyl methacrylate, N-(isobutoxy)methacrylamide and azobisisobutyronitrile over a period of 1-2 hours. After the dripping is complete, the temperature will be controlled for 2-3 hours until it reaches room temperature to obtain the improved acrylic adhesive layer.

5. A method for preparing an SCF module buffer film, used to prepare any one of the SCF module buffer films as described in claims 1 to 4, characterized in that, The steps include the following: S1: Preparation of modified acrylic adhesive; S2: Preparation of acrylic adhesive for the improvement layer; S3: Take the modified acrylic adhesive synthesized in S1, mix it with isocyanate curing agent, stir it in a mixing tank at 300-400r / min for 15min, and then apply the acrylic buffer layer. S4: Take the improved acrylic adhesive synthesized in S2, add solvent to reduce solid content and viscosity, and mix with isocyanate curing agent. After mixing in a mixing tank at 200-300r / min for 15min, apply the bonding improvement layer to obtain the finished SCF component buffer film.

6. The method for preparing an SCF component buffer film according to claim 5, characterized in that: The isocyanate curing agent used in step S3 is an aliphatic isocyanate.

7. The method for preparing an SCF component buffer film according to claim 6, characterized in that: The aliphatic isocyanate is hexamethylene diisocyanate, and its addition amount is 0.5% by weight.

8. The method for preparing an SCF component buffer film according to claim 5, characterized in that: The isocyanate curing agent used in step S4 is an aromatic isocyanate.

9. The SCF component buffer film and its preparation method according to claim 8, characterized in that: The aromatic isocyanate is toluene diisocyanate (TDI, L75), and its addition amount is 1% by weight.

10. The method for preparing an SCF component buffer film according to claim 5, characterized in that: The bonding strength improvement layer is uniformly coated on both sides of the acrylic buffer layer, wherein the thickness of the acrylic buffer layer is 90-95μm, and the thickness of the bonding strength improvement layer is 4-5% of the thickness of the acrylic buffer layer.

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