High-performance pre-cured conductive adhesive film and preparation method thereof

Abstract

The application discloses a high-performance pre-cured conductive adhesive film and a preparation method thereof, which comprises a pre-cured conductive adhesive film layer and a release film protective layer; the conductive adhesive film layer comprises the following components according to weight parts: 100 parts of epoxy resin, 400-800 parts of conductive filler, 2-5 parts of active diluent, 5-20 parts of toughening agent, 5-20 parts of latent curing agent, 2-5 parts of addition curing agent, 0.2-2 parts of accelerator, 1-2 parts of coupling agent and 10-20 parts of solvent, wherein the amount of the epoxy resin is calculated based on 100 parts of the epoxy resin; the release film protective layer comprises a substrate layer located below the conductive adhesive film layer and a back film layer covering the conductive adhesive film. In the preparation process, the pre-curing degree and film-forming property of the conductive adhesive film are effectively controlled through the use of the addition curing agent, and the conductive adhesive film can meet the use of large-format bonding construction in subsequent specific use processes.

Description

Technical Field

[0001] This invention relates to the field of conductive adhesive technology, and in particular to a high-performance pre-cured conductive adhesive film and its preparation method. Background Technology

[0002] Conductive adhesive is a widely used conductive material in semiconductor packaging, component lead connections, and electromagnetic shielding. Currently, due to different manufacturing processes, there are many types of conductive adhesive products on the market. Mainstream products are from companies such as 3M, Epoxy Technology, Park, and Ablistick, including products like H20E, MD140, and DA5100. Recently, domestic conductive adhesive manufacturers, such as Zhonglan Chenguang Chemical Research and Design Institute Co., Ltd. and Changchun Yonggu Technology Co., Ltd., have been gradually opening up the domestic conductive adhesive market. These products are increasingly being used in high-end fields such as chip packaging and microelectronic bonding, significantly contributing to breaking the long-standing foreign monopoly.

[0003] Currently, most conductive adhesive products on the market are in viscous paste or liquid form, which poses significant challenges for large-format bonding and cannot guarantee uniform thickness of the adhesive over large areas. Furthermore, the application process is complex and cannot meet the needs of large-scale continuous use. In recent years, conductive adhesive films have effectively solved the demand for large-format conductive bonding. Currently, the use of conductive adhesive films in China is mainly dominated by products from foreign manufacturers, such as Henkel's CF3350 conductive adhesive film and 3M's C-TSF2201P conductive adhesive film. There are few reports on conductive adhesive film products in China, mainly concentrated in research institutions, with related reports focusing primarily on basic formulation design and filler modification. Patent CN104017511B provides a method for preparing an epoxy resin conductive adhesive film, which describes the components of the conductive adhesive layer and the corresponding preparation process. However, the bonding strength between the conductive adhesive film and the substrate in this patent cannot guarantee whether it meets the high-end application requirements of large-format bonding with high adhesion. Patent CN109294506A discloses a conductive adhesive film and its preparation method. This patent uses silver-plated copper powder, silver-plated nickel powder, and gold-plated nickel powder as conductive metals, and epoxy resin and polyurethane resin as the main resins for the conductive adhesive film, preparing a series of conductive adhesive films with different thicknesses. However, this patent does not analyze the mechanical and physical properties of the adhesive film. Patent CN110527456A discloses a method for using a photovoltaic conductive adhesive film. This patent uses hyperbranched polyester-modified epoxy resin as the main resin. However, this patent does not analyze the adhesion strength, volume resistivity, and thermal conductivity between the conductive adhesive film and the substrate.

[0004] Therefore, in response to the problems existing in the domestically produced conductive adhesive films, it is necessary to develop a conductive adhesive film product with excellent comprehensive performance, thereby breaking the monopoly of foreign manufacturers in the field of conductive adhesive film technology and providing a solid foundation for the stable production and preparation of high-performance conductive adhesive films in my country. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes a high-performance pre-cured conductive adhesive film and its preparation method. During the preparation process, the degree of pre-curing and film-forming properties are effectively controlled by the use of an addition-type curing agent, meeting the requirements for large-format bonding in subsequent application processes. The conductive adhesive film prepared by this method exhibits excellent flexibility, enabling effective bonding to curved, wrinkled, and other irregular surfaces. The use of different types of solvents ensures uniform evaporation of the slurry solvents at different drying tunnel temperatures, resulting in a smooth and uniform surface on the conductive adhesive film.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A high-performance pre-cured conductive adhesive film, characterized in that it comprises a pre-cured conductive adhesive film layer and a release film protective layer; the conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin,

[0008]

[0009] The release film protective layer includes a base layer located below the conductive adhesive film layer and a back film layer covering the conductive adhesive film.

[0010] Preferably, the epoxy resin is one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy resin, and glycidylamine type epoxy resin.

[0011] Preferably, the conductive filler is one or more of flake silver powder with a particle size of 2-30 μm and spherical silver powder with a particle size of 2-15 μm.

[0012] Preferably, the conductive filler is one or more of flake silver powder with a particle size of 5-10 μm and spherical silver powder with a particle size of 2-5 μm.

[0013] Preferably, the active diluent is one or more of glycidyl ether diluents or glycidyl ester diluents.

[0014] Preferably, the active diluent is ethylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycidyl tert-carbonate, or glycidyl methacrylate.

[0015] Preferably, the toughening agent is one or more of nitrile rubber and polyurethane resin.

[0016] Preferably, the latent curing agent is one or more of dicyandiamide, organic urea, modified imidazole, and phenolic resin type curing agents; the addition-type curing agent is one or more of polyetheramine, polyamide, fatty amine, and aromatic amine.

[0017] Preferably, the latent curing agent is dicyandiamide, and the addition-type curing agent is polyetheramine.

[0018] Preferably, the accelerator is one or more of modified imidazole, tertiary amines (1,2,4,6-tris(dimethylaminomethyl), benzyldimethylamine).

[0019] Preferably, the coupling agent is a silane coupling agent.

[0020] Preferably, the coupling agent is one or more of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, trichlorovinylsilane, triethoxyvinylsilane, γ-aminopropyltriethoxysilane, and trichloropropenylsilane.

[0021] Preferably, the solvent is one or more of acetone, toluene, xylene, ethyl acetate, butanone, n-butanol, cyclohexanone, and N,N-dimethylformamide.

[0022] Preferably, the base layer and the back film layer are PET films or release paper with a thickness of 50 to 200 μm.

[0023] A method for preparing a high-performance pre-cured conductive adhesive film, characterized by the following process steps:

[0024] Step A: Mix and stir the epoxy resin, reactive diluent, toughening agent, latent curing agent, coupling agent and 50% of the solvent under a sealed condition. Stir at a speed of 500-1000 r / min for 10-20 min until the mixture is evenly dispersed.

[0025] Step B: Then add the conductive filler and the remaining 50% of the solvent to the adhesive in Step A, and mix in a closed container for 10 to 15 minutes at 1500 to 2500 r / min.

[0026] Step C: Add the addition curing agent and accelerator to the mixed adhesive from step B, and mix in a closed container at 500-1000 r / min for 5-10 min to obtain the slurry for preparing the high-performance pre-cured conductive adhesive film.

[0027] Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the base layer release film using a casting machine. After pre-curing by heating, the back film layer is covered by a coating roller. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

[0028] Preferably, in step D, during the pre-curing and molding process of the adhesive film, the temperature of the drying tunnel and other relevant parameters at each stage of the casting machine are set as follows:

[0029] A. Temperature of the drying tunnel at each stage of the casting machine

[0030] Drying tunnel number 1 2 3 4 5 6 7 8 9 10 Temperature (°C) 35 50 65 80 80 80 80 50 room temperature room temperature

[0031] Drying tunnels 1-3 are the solvent evaporation stage;

[0032] Drying tunnels 4 to 7 are the pre-curing and film-forming stages of the conductive adhesive film;

[0033] Drying tunnel 8 is a temperature buffer stage;

[0034] Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film.

[0035] B. Other relevant parameters of the casting machine:

[0036] The casting speed was set to 1.5 m / min;

[0037] Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°;

[0038] Baseband tension 30N, winding tension 50N.

[0039] The beneficial effects of this technical solution are as follows:

[0040] I. This invention provides a high-performance pre-cured conductive adhesive film. The finished conductive adhesive film (before curing) has the following properties: gray or brownish-gray appearance, with an intermediate adhesive layer thickness of 50–200 μm; the conductive adhesive film (after curing) has the following properties: glass transition temperature Tg ≥ 85℃, thermal conductivity ≥ 7 W / m·K, and volume resistivity ≤ 5 × 10⁻⁶. -4 Ω·cm, shear strength ≥15.0MPa, porosity ≤10%, coefficient of thermal expansion ≤65ppm / ℃ (below Tg), ≤150ppm / ℃ (above Tg).

[0041] II. This invention provides a method for preparing a high-performance pre-cured conductive adhesive film. During the preparation process, the degree of pre-curing and film-forming properties are effectively controlled by the use of an addition-type curing agent, which can meet the requirements of large-format bonding construction in subsequent specific application processes. The conductive adhesive film prepared by this method has excellent flexibility and can meet the requirements of effective bonding to curved, wrinkled and other irregular surfaces. By using different types of solvents in combination, the uniform evaporation of the slurry solvent at different drying tunnel temperatures is ensured, thereby making the conductive adhesive film present a smooth and uniform surface. Attached Figure Description

[0042] Figure 1 This is the conductive adhesive film cured according to Example 1 of the present invention;

[0043] Figure 2 The DMA spectrum of the conductive adhesive film after curing in Embodiment 1 of the present invention (left: storage modulus and loss modulus curves; right: loss factor curve); Detailed Implementation

[0044] 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.

[0045] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicating orientation or positional relationships, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0046] Example 1

[0047] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0048] Epoxy resins: Bisphenol A type epoxy resin 45; Glycidyl amine type epoxy resin 55;

[0049] Conductive fillers: 700 flake silver powders with an average particle size of 7.4 μm; 100 spherical silver powders with an average particle size of 2.2 μm;

[0050] Reactive diluent: 1,6-hexanediol diglycidyl ether 5;

[0051] Toughening agent: Nitrile rubber toughening agent 18;

[0052] Latent curing agent: Dicyandiamide 9;

[0053] Addition-type curing agent: polyetheramine 2.1;

[0054] Accelerator: Modified imidazole accelerator 0.4;

[0055] Coupling agent: γ-(2,3-epoxypropoxy)propyltrimethoxysilane 2;

[0056] Solvents: Toluene 5%; N,N-dimethylformamide 5%;

[0057] The base layer and back film layer are release paper with a thickness of 5 μm.

[0058] A method for preparing a high-performance pre-cured conductive adhesive film includes the following steps:

[0059] Step A: Mix and stir the epoxy resin, reactive diluent, toughening agent, latent curing agent, coupling agent and 50% of the solvent under a sealed condition. Stir at 1000 r / min for 10 min until the mixture is evenly dispersed.

[0060] Step B: Then add the conductive filler and the remaining 50% of the solvent to the adhesive in Step A, and mix in a sealed container at 2500 r / min for 10 min.

[0061] Step C: Add the addition curing agent and accelerator to the mixed adhesive from step B, and mix in a closed container at 1000 r / min for 5 min to obtain the slurry for preparing the high-performance pre-cured conductive adhesive film.

[0062] Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the base layer release film using a casting machine. After pre-curing by heating, the back film layer is covered by pressure. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

[0063] During the pre-curing and molding process of the adhesive film, the temperature and other relevant parameters of the drying tunnel at each stage of the casting machine are set as follows:

[0064] A. Temperature of the drying tunnel at each stage of the casting machine

[0065] Drying tunnel number 1 2 3 4 5 6 7 8 9 10 Temperature (°C) 35 50 65 80 80 80 80 50 room temperature room temperature

[0066] Drying tunnels 1-3 are the solvent evaporation stage;

[0067] Drying tunnels 4 to 7 are the pre-curing and film-forming stages of the conductive adhesive film;

[0068] Drying tunnel 8 is a temperature buffer stage;

[0069] Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film.

[0070] B. Other relevant parameters of the casting machine

[0071] The casting speed was set to 1.5 m / min;

[0072] Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°;

[0073] Baseband tension 30N, winding tension 50N.

[0074] The above steps yield high-performance pre-cured conductive adhesive film product A. A photo of product A is shown below. Figure 1 As shown, the DMA spectrum of product A is as follows: Figure 2 As shown.

[0075] Example 2

[0076] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0077] Resin: Bisphenol F type epoxy resin 100;

[0078] Conductive filler: 400 flake silver powders with an average particle size of 5μm;

[0079] Reactive diluent: ethylene glycol diglycidyl ether 2;

[0080] Toughening agent: Polyurethane resin 5;

[0081] Latent curing agents: organic urea 2; modified imidazole 3;

[0082] Addition-curing agents: polyamide 1; fatty amine 1;

[0083] Accelerator: 1,2,4,6-tris(dimethylaminomethyl) 0.2;

[0084] Coupling agent: γ-(2,3-epoxypropoxy)propyltrimethoxysilane 1;

[0085] Solvents: xylene 5; ethyl acetate 5; butanone 5;

[0086] The base layer and back film layer are PET films with a thickness of 200 μm.

[0087] A method for preparing a high-performance pre-cured conductive adhesive film includes the following steps:

[0088] Step A: Mix and stir the epoxy resin, reactive diluent, toughening agent, latent curing agent, coupling agent and 50% of the solvent under a sealed condition. Stir at 1000 r / min for 10 min until the mixture is evenly dispersed.

[0089] Step B: Then add the conductive filler and the remaining 50% of the solvent to the adhesive in Step A, and mix in a sealed container at 2500 r / min for 10 min.

[0090] Step C: Add the addition curing agent and accelerator to the mixed adhesive from step B, and mix in a closed container at 1000 r / min for 5 min to obtain the slurry for preparing the high-performance pre-cured conductive adhesive film.

[0091] Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the base layer release film using a casting machine. After pre-curing by heating, the back film layer is covered by pressure. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

[0092] During the pre-curing and molding process of the adhesive film, the temperature and other relevant parameters of the drying tunnel at each stage of the casting machine are set as follows:

[0093] A. Temperature of the drying tunnel at each stage of the casting machine

[0094] Drying tunnel number 1 2 3 4 5 6 7 8 9 10 Temperature (°C) 35 50 65 80 80 80 80 50 room temperature room temperature

[0095] Drying tunnels 1-3 are the solvent evaporation stage;

[0096] Drying tunnels 4 to 7 are the pre-curing and film-forming stages of the conductive adhesive film;

[0097] Drying tunnel 8 is a temperature buffer stage;

[0098] Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film.

[0099] B. Other relevant parameters of the casting machine

[0100] The casting speed was set to 1.5 m / min;

[0101] Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°;

[0102] Baseband tension 30N, winding tension 50N.

[0103] The above steps yield high-performance pre-cured conductive adhesive film product B.

[0104] Example 3

[0105] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0106] Resin: 100g phenolic epoxy resin;

[0107] Conductive filler: 600 spherical silver powder with an average particle size of 5μm;

[0108] Reactive diluent: 1,4-Butanediol diglycidyl ether 3;

[0109] Toughening agent: Polyurethane resin 20;

[0110] Latent curing agent: Phenolic resin type curing agent 20;

[0111] Addition-type curing agent: Aromatic amine 5;

[0112] Accelerator: Benzyldimethylamine 2;

[0113] Coupling agents: Triethoxyvinylsilane 1; γ-aminopropyltriethoxysilane 0.5;

[0114] Solvents: n-Butanol 10; Cyclohexanone 10;

[0115] The base layer and back film layer are release paper with a thickness of 100 μm.

[0116] A method for preparing a high-performance pre-cured conductive adhesive film includes the following steps:

[0117] Step A: Mix and stir the epoxy resin, reactive diluent, toughening agent, latent curing agent, coupling agent and 50% of the solvent under a sealed condition. Stir at 1000 r / min for 10 min until the mixture is evenly dispersed.

[0118] Step B: Then add the conductive filler and the remaining 50% of the solvent to the adhesive in Step A, and mix in a sealed container at 2500 r / min for 10 min.

[0119] Step C: Add the addition curing agent and accelerator to the mixed adhesive from step B, and mix in a closed container at 1000 r / min for 5 min to obtain the slurry for preparing the high-performance pre-cured conductive adhesive film.

[0120] Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the base layer release film using a casting machine. After pre-curing by heating, the back film layer is covered by pressure. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

[0121] During the pre-curing and molding process of the adhesive film, the temperature and other relevant parameters of the drying tunnel at each stage of the casting machine are set as follows:

[0122] A. Temperature of the drying tunnel at each stage of the casting machine

[0123] Drying tunnel number 1 2 3 4 5 6 7 8 9 10 Temperature (°C) 35 50 65 80 80 80 80 50 room temperature room temperature

[0124] Drying tunnels 1-3 are the solvent evaporation stage;

[0125] Drying tunnels 4 to 7 are the pre-curing and film-forming stages of the conductive adhesive film;

[0126] Drying tunnel 8 is a temperature buffer stage;

[0127] Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film.

[0128] B. Other relevant parameters of the casting machine

[0129] The casting speed was set to 1.5 m / min;

[0130] Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°;

[0131] Baseband tension 30N, winding tension 50N.

[0132] The above steps yield high-performance pre-cured conductive adhesive film product C.

[0133] Example 4

[0134] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0135] Resins: 30g bisphenol F type epoxy resin; 30g phenolic epoxy resin; 40g glycidylamine type epoxy resin;

[0136] Conductive fillers: 300 flake silver powders with an average particle size of 5μm; 300 spherical silver powders with an average particle size of 5μm;

[0137] Reactive diluent: 1,6-hexanediol diglycidyl ether 3;

[0138] Toughening agent: Nitrile rubber 10;

[0139] Latent curing agent: Dicyandiamide 15;

[0140] Addition-type curing agent: polyetheramine 4;

[0141] Accelerator: Modified imidazole 1;

[0142] Coupling agent: γ-(2,3-epoxypropoxy)propyltrimethoxysilane 1.5;

[0143] Solvent: 15g acetone;

[0144] The base layer and back film layer are PET films with a thickness of 200 μm.

[0145] A method for preparing a high-performance pre-cured conductive adhesive film includes the following steps:

[0146] Step A: Mix and stir the epoxy resin, reactive diluent, toughening agent, latent curing agent, coupling agent and 50% of the solvent under a sealed condition. Stir at 1000 r / min for 10 min until the mixture is evenly dispersed.

[0147] Step B: Then add the conductive filler and the remaining 50% of the solvent to the adhesive in Step A, and mix in a sealed container at 2500 r / min for 10 min.

[0148] Step C: Add the addition curing agent and accelerator to the mixed adhesive from step B, and mix in a closed container at 1000 r / min for 5 min to obtain the slurry for preparing the high-performance pre-cured conductive adhesive film.

[0149] Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the base layer release film using a casting machine. After pre-curing by heating, the back film layer is covered by pressure. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

[0150] During the pre-curing and molding process of the adhesive film, the temperature and other relevant parameters of the drying tunnel at each stage of the casting machine are set as follows:

[0151] A. Temperature of the drying tunnel at each stage of the casting machine

[0152] Drying tunnel number 1 2 3 4 5 6 7 8 9 10 Temperature (°C) 35 50 65 80 80 80 80 50 room temperature room temperature

[0153] Drying tunnels 1-3 are the solvent evaporation stage;

[0154] Drying tunnels 4 to 7 are the pre-curing and film-forming stages of the conductive adhesive film;

[0155] Drying tunnel 8 is a temperature buffer stage;

[0156] Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film.

[0157] B. Other relevant parameters of the casting machine

[0158] The casting speed was set to 1.5 m / min;

[0159] Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°;

[0160] Baseband tension 30N, winding tension 50N.

[0161] The above steps yield the high-performance pre-cured conductive adhesive film product D.

[0162] Comparison 1

[0163] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0164]

[0165]

[0166] The base layer and back film layer are release paper.

[0167] A method for preparing a high-performance pre-cured conductive adhesive film includes the following steps:

[0168] Step A: Bisphenol A epoxy resin, glycidylamine epoxy resin, 1,6-hexanediol diglycidyl ether, nitrile rubber toughening agent, dicyandiamide, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, and 50% of toluene and N,N-dimethylformamide are mixed and stirred under a closed system at a stirring speed of 1000 r / min for 10 min until uniformly dispersed.

[0169] Step B: Then add the flake silver powder, spherical silver powder, and the remaining 50% of toluene and N,N-dimethylformamide to the adhesive in Step A, and mix in a sealed container at 2500 r / min for 10 min.

[0170] Step C: Add polyetheramine and modified imidazole accelerator to the mixed adhesive from step B, and mix in a closed container at 1000 r / min for 5 min to obtain the slurry for preparing high-performance pre-cured conductive adhesive film.

[0171] Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the base layer release film using a casting machine. After pre-curing by heating, the back film layer is covered by pressure. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

[0172] During the pre-curing and molding process of the adhesive film, the temperature and other relevant parameters of the drying tunnel at each stage of the casting machine are set as follows:

[0173] A. Temperature of the drying tunnel at each stage of the casting machine

[0174] Drying tunnel number 1 2 3 4 5 6 7 8 9 10 Temperature (°C) 35 50 65 80 80 80 80 50 room temperature room temperature

[0175] Drying tunnels 1-3 are the solvent evaporation stage;

[0176] Drying tunnels 4 to 7 are the pre-curing and film-forming stages of the conductive adhesive film;

[0177] Drying tunnel 8 is a temperature buffer stage;

[0178] Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film.

[0179] B. Other relevant parameters of the casting machine

[0180] The casting speed was set to 1.5 m / min;

[0181] Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°;

[0182] Baseband tension 30N, winding tension 50N.

[0183] The high-performance pre-cured conductive adhesive film product A1 is obtained through the above steps.

[0184] Comparative Example 2

[0185] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0186]

[0187] The base layer and back film layer are release paper.

[0188] A method for preparing a high-performance pre-cured conductive adhesive film includes the following steps:

[0189] Step A: Bisphenol A epoxy resin, glycidylamine epoxy resin, 1,6-hexanediol diglycidyl ether, nitrile rubber toughening agent, dicyandiamide, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, and 100% of toluene and N,N-dimethylformamide are mixed and stirred under a closed system at a stirring speed of 1000 r / min for 10 min until uniformly dispersed.

[0190] Step B: Then add the flake silver powder and spherical silver powder to the adhesive in Step A, and mix in a sealed environment at 2500 r / min for 10 min.

[0191] Step C: Add polyetheramine and modified imidazole accelerator to the mixed adhesive from step B, and mix in a closed container at 1000 r / min for 5 min to obtain the slurry for preparing high-performance pre-cured conductive adhesive film.

[0192] Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the base layer release film using a casting machine. After pre-curing by heating, the back film layer is covered by pressure. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

[0193] During the pre-curing and molding process of the adhesive film, the temperature and other relevant parameters of the drying tunnel at each stage of the casting machine are set as follows:

[0194] A. Temperature of the drying tunnel at each stage of the casting machine

[0195] Drying tunnel number 1 2 3 4 5 6 7 8 9 10 Temperature (°C) 35 50 65 80 80 80 80 50 room temperature room temperature

[0196] Drying tunnels 1-3 are the solvent evaporation stage;

[0197] Drying tunnels 4 to 7 are the pre-curing and film-forming stages of the conductive adhesive film;

[0198] Drying tunnel 8 is a temperature buffer stage;

[0199] Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film.

[0200] B. Other relevant parameters of the casting machine

[0201] The casting speed was set to 1.5 m / min;

[0202] Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°;

[0203] Baseband tension 30N, winding tension 50N.

[0204] The above steps yield the high-performance pre-cured conductive adhesive film product A2.

[0205] Comparative Example 3

[0206] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0207]

[0208] The base layer and back film layer are release paper.

[0209] A method for preparing a high-performance pre-cured conductive adhesive film includes the following steps:

[0210] Step A: Bisphenol A epoxy resin, glycidylamine epoxy resin, 1,6-hexanediol diglycidyl ether, nitrile rubber toughening agent, dicyandiamide, polyetheramine, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, and 50% of toluene and N,N-dimethylformamide are mixed and stirred under a closed system at a stirring speed of 1000 r / min for 10 min until uniformly dispersed.

[0211] Step B: Then add the flake silver powder, spherical silver powder, and the remaining 50% of toluene and N,N-dimethylformamide to the adhesive in Step A, and mix in a sealed container at 2500 r / min for 10 min.

[0212] Step C: Add the modified imidazole accelerator to the mixed adhesive in step B, and mix in a closed container at 1000 r / min for 5 min to obtain the slurry for preparing the high-performance pre-cured conductive adhesive film.

[0213] Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the base layer release film using a casting machine. After pre-curing by heating, the back film layer is covered by pressure. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

[0214] During the pre-curing and molding process of the adhesive film, the temperature and other relevant parameters of the drying tunnel at each stage of the casting machine are set as follows:

[0215] A. Temperature of the drying tunnel at each stage of the casting machine

[0216] Drying tunnel number 1 2 3 4 5 6 7 8 9 10 Temperature (°C) 35 50 65 80 80 80 80 50 room temperature room temperature

[0217] Drying tunnels 1-3 are the solvent evaporation stage;

[0218] Drying tunnels 4 to 7 are the pre-curing and film-forming stages of the conductive adhesive film;

[0219] Drying tunnel 8 is a temperature buffer stage;

[0220] Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film.

[0221] B. Other relevant parameters of the casting machine

[0222] The casting speed was set to 1.5 m / min;

[0223] Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°;

[0224] Baseband tension 30N, winding tension 50N.

[0225] The high-performance pre-cured conductive adhesive film product A3 is obtained by following the above steps.

[0226] Comparative Example 4

[0227] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0228] Resin: Bisphenol F type epoxy resin 100;

[0229] Conductive filler: 300 flake silver powders with an average particle size of 5μm;

[0230] Reactive diluent: ethylene glycol diglycidyl ether 2;

[0231] Toughening agent: Polyurethane resin 5;

[0232] Latent curing agents: organic urea 2; modified imidazole 3;

[0233] Addition-curing agents: polyamide 1; fatty amine 1;

[0234] Accelerator: 1,2,4,6-tris(dimethylaminomethyl) 0.2;

[0235] Coupling agent: γ-(2,3-epoxypropoxy)propyltrimethoxysilane 1;

[0236] Solvents: xylene 5; ethyl acetate 5; butanone 5;

[0237] The base layer and back film layer are PET films with a thickness of 200 μm.

[0238] The preparation method of a high-performance pre-cured conductive adhesive film is the same as that in Example 2. The high-performance pre-cured conductive adhesive film product B1 is obtained through the above steps.

[0239] Comparative Example 5

[0240] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0241] Resin: Bisphenol F type epoxy resin 100;

[0242] Conductive filler: 900 flake silver powders with an average particle size of 5μm;

[0243] Reactive diluent: ethylene glycol diglycidyl ether 2;

[0244] Toughening agent: Polyurethane resin 5;

[0245] Latent curing agents: organic urea 2; modified imidazole 3;

[0246] Addition-curing agents: polyamide 1; fatty amine 1;

[0247] Accelerator: 1,2,4,6-tris(dimethylaminomethyl) 0.2;

[0248] Coupling agent: γ-(2,3-epoxypropoxy)propyltrimethoxysilane 1;

[0249] Solvents: xylene 5; ethyl acetate 5; butanone 5;

[0250] The base layer and back film layer are PET films with a thickness of 200 μm.

[0251] The preparation method of a high-performance pre-cured conductive adhesive film is the same as that in Example 2. The high-performance pre-cured conductive adhesive film product B2 is obtained through the above steps.

[0252] Comparative Example 6

[0253] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0254] Resin: 100g phenolic epoxy resin;

[0255] Conductive filler: 600 spherical silver powder with an average particle size of 5μm;

[0256] Reactive diluent: 1,4-Butanediol diglycidyl ether 3;

[0257] Toughening agent: Polyurethane resin 20;

[0258] Latent curing agent: Phenolic resin type curing agent 4;

[0259] Addition-type curing agent: Aromatic amine 5;

[0260] Accelerator: Benzyldimethylamine 2;

[0261] Coupling agents: Triethoxyvinylsilane 1; γ-aminopropyltriethoxysilane 0.5;

[0262] Solvents: n-Butanol 10; Cyclohexanone 10;

[0263] The base layer and back film layer are release paper with a thickness of 100 μm.

[0264] The preparation method of a high-performance pre-cured conductive adhesive film is the same as that in Example 3. The high-performance pre-cured conductive adhesive film product C1 is obtained through the above steps.

[0265] Comparative Example 7

[0266] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0267] Resin: 100g phenolic epoxy resin;

[0268] Conductive filler: 600 spherical silver powder with an average particle size of 5μm;

[0269] Reactive diluent: 1,4-Butanediol diglycidyl ether 3;

[0270] Toughening agent: Polyurethane resin 20;

[0271] Latent curing agent: Phenolic resin type curing agent 22;

[0272] Addition-type curing agent: Aromatic amine 5;

[0273] Accelerator: Benzyldimethylamine 2;

[0274] Coupling agents: Triethoxyvinylsilane 1; γ-aminopropyltriethoxysilane 0.5;

[0275] Solvents: n-Butanol 10; Cyclohexanone 10;

[0276] The base layer and back film layer are release paper with a thickness of 100 μm.

[0277] The preparation method of a high-performance pre-cured conductive adhesive film is the same as that in Example 3. The high-performance pre-cured conductive adhesive film product C2 is obtained through the above steps.

[0278] Comparative Example 8

[0279] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0280] Resins: 30g bisphenol F type epoxy resin; 30g phenolic epoxy resin; 40g glycidylamine type epoxy resin;

[0281] Conductive fillers: 300 flake silver powders with an average particle size of 5μm; 300 spherical silver powders with an average particle size of 5μm;

[0282] Reactive diluent: 1,6-hexanediol diglycidyl ether 3;

[0283] Toughening agent: Nitrile rubber 10;

[0284] Latent curing agent: Dicyandiamide 15;

[0285] Addition-type curing agent: polyetheramine 1.5;

[0286] Accelerator: Modified imidazole 1;

[0287] Coupling agent: γ-(2,3-epoxypropoxy)propyltrimethoxysilane 1.5;

[0288] Solvent: 15g acetone;

[0289] The base layer and back film layer are PET films with a thickness of 200 μm.

[0290] The preparation method of a high-performance pre-cured conductive adhesive film is the same as that of Example 4. The high-performance pre-cured conductive adhesive film product D1 is obtained through the above steps.

[0291] Comparative Example 9

[0292] The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin

[0293] Resins: 30g bisphenol F type epoxy resin; 30g phenolic epoxy resin; 40g glycidylamine type epoxy resin;

[0294] Conductive fillers: 300 flake silver powders with an average particle size of 5μm; 300 spherical silver powders with an average particle size of 5μm;

[0295] Reactive diluent: 1,6-hexanediol diglycidyl ether 3;

[0296] Toughening agent: Nitrile rubber 10;

[0297] Latent curing agent: Dicyandiamide 15;

[0298] Addition-type curing agent: polyetheramine 5.5;

[0299] Accelerator: Modified imidazole 1;

[0300] Coupling agent: γ-(2,3-epoxypropoxy)propyltrimethoxysilane 1.5;

[0301] Solvent: 15g acetone;

[0302] The base layer and back film layer are PET films with a thickness of 200 μm.

[0303] The preparation method of a high-performance pre-cured conductive adhesive film is the same as that of Example 4. The high-performance pre-cured conductive adhesive film product D2 is obtained through the above steps.

[0304] Performance comparison:

[0305] The high-performance pre-cured conductive adhesive film products obtained above were subjected to heat curing at 130℃ for 3 hours. The performance of each conductive adhesive film was compared, and the performance testing standards for the cured conductive adhesive films were as follows:

[0306] Shear strength: in accordance with GB / T 7124-2008 standard;

[0307] Volume resistivity: in accordance with QJ 1523-1988 standard;

[0308] Thermal conductivity: in accordance with GB / T 22588-2008 standard;

[0309] Porosity: Compliant with GJB 548B-2005 standard;

[0310] Glass transition temperature Tg: in accordance with GB / T 35494.1-2017 standard;

[0311] Coefficient of thermal expansion: Complies with GB / T 36800.2-2018 standard; see the table below for details:

[0312]

[0313]

[0314] As can be seen from the above, by using the conductive adhesive film layer of the present invention according to the various components in the weight parts and the preparation method of a high-performance pre-cured conductive adhesive film, a high-performance pre-cured conductive adhesive film that meets the standards can be obtained.

[0315] In summary, any other corresponding modifications made by those skilled in the art after reading this invention document, without requiring creative mental effort, based on the technical solutions and concepts of this invention, are all within the scope of protection of this invention.

Claims

1. A high-performance pre-cured conductive adhesive film, characterized in that: Includes a pre-cured conductive adhesive film layer and a release film protective layer; The conductive adhesive film layer comprises the following components by weight: per 100 parts epoxy resin Epoxy resin 100; Conductive filler 400~800; 2-5% reactive diluent; Toughening agent 5~20; Latent curing agent 5~20; Addition curing agent 2~5; Accelerator 0.2~2; Coupling agent 1~2; Solvent 10~20; The release film protective layer includes a base layer located below the conductive adhesive film layer and a back film layer covering the conductive adhesive film. The conductive filler is one or more of flake silver powder with a particle size of 2~30μm and spherical silver powder with a particle size of 2~15μm. The latent curing agent is one or more of dicyandiamide, organic urea, modified imidazole, and phenolic resin type curing agents; the addition-type curing agent is one or more of polyetheramine, polyamide, fatty amine, and aromatic amine. The preparation process of the high-performance pre-cured conductive adhesive film is as follows: Step A: Mix and stir the epoxy resin, reactive diluent, toughening agent, latent curing agent, coupling agent and 50% of the solvent under a sealed condition. Stir at a speed of 500~1000 r / min for 10~20 min until the mixture is evenly dispersed. Step B: Then add the conductive filler and the remaining 50% of the solvent to the adhesive in Step A, and mix in a closed container for 10 to 15 minutes at 1500 to 2500 r / min. Step C: Add the addition curing agent and accelerator to the mixed adhesive from step B, and mix in a closed system at 500-1000 r / min for 5-10 min to obtain the slurry for preparing the high-performance pre-cured conductive adhesive film. Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the substrate using a casting machine. After pre-curing by heating, the back film layer is covered by a coating roller. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

2. The high-performance pre-cured conductive adhesive film according to claim 1, characterized in that: The epoxy resin is one or more of the following: bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy resin, and glycidylamine type epoxy resin.

3. The high-performance pre-cured conductive adhesive film according to claim 2, characterized in that: The active diluent is one or more of glycidyl ether diluents or glycidyl ester diluents.

4. The high-performance pre-cured conductive adhesive film according to claim 3, characterized in that: The toughening agent is one or more of nitrile rubber and polyurethane resin.

5. The high-performance pre-cured conductive adhesive film according to claim 4, characterized in that: The coupling agent is a silane coupling agent; the solvent is one or more of acetone, toluene, xylene, ethyl acetate, butanone, n-butanol, cyclohexanone, and N,N-dimethylformamide.

6. The high-performance pre-cured conductive adhesive film according to claim 5, characterized in that: The base layer and back film layer are PET films or release paper with a thickness of 50~200μm.

7. A method for preparing a high-performance pre-cured conductive adhesive film according to any one of claims 1-6, characterized in that, The process steps are as follows: Step A: Mix and stir the epoxy resin, reactive diluent, toughening agent, latent curing agent, coupling agent and 50% of the solvent under a sealed condition. Stir at a speed of 500~1000 r / min for 10~20 min until the mixture is evenly dispersed. Step B: Then add the conductive filler and the remaining 50% of the solvent to the adhesive in Step A, and mix in a closed container for 10 to 15 minutes at 1500 to 2500 r / min. Step C: Add the addition curing agent and accelerator to the mixed adhesive from step B, and mix in a closed system at 500-1000 r / min for 5-10 min to obtain the slurry for preparing the high-performance pre-cured conductive adhesive film. Step D: The prepared conductive adhesive film slurry is uniformly coated onto the surface of the substrate using a casting machine. After pre-curing by heating, the back film layer is covered by a coating roller. Finally, the high-performance pre-cured conductive adhesive film is obtained through winding and cutting processes.

8. The method for preparing a high-performance pre-cured conductive adhesive film according to claim 7, characterized in that: In step D, during the pre-curing and molding of the adhesive film, the temperature and other relevant parameters of the drying tunnel at each stage of the casting machine are set as follows: A. Temperature of the drying tunnel at each stage of the casting machine Drying tunnel 1 temperature: 35℃; Drying tunnel 2 temperature: 50℃; Drying tunnel 3 temperature: 65℃; Drying tunnel 4 temperature: 80℃; Drying tunnel 5 temperature: 80℃; Drying tunnel 6 temperature: 80℃; Drying tunnel 7 temperature: 80℃; Drying tunnel 8 temperature: 80℃; Drying tunnel 9 temperature: room temperature; Drying tunnel 10 temperature: room temperature; Drying tunnels 1-3 are the solvent evaporation stage; Drying tunnels 4-7 are the pre-curing and film-forming stages of the conductive adhesive film. Drying tunnel 8 is a temperature buffer stage; Drying tunnels 9 and 10 are the cooling stages for the conductive adhesive film; B. Other relevant parameters of the casting machine: The casting speed was set to 1.5 m / min; Front winding swing arm 90°, upper winding swing arm 90°, baseband swing arm 90°; Baseband tension 30N, winding tension 50N.

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