A method for improving overflow of hot-pressing insulation film, and hot-pressing insulation film, and a preparation method and use method thereof

Abstract

The present application provides a method for improving overflow of hot-pressed insulation film, and a hot-pressed insulation film, a preparation method and a use method thereof. A resin rich in active functional groups is added to the adhesive layer, and the resin rich in active functional groups is at least one of unsaturated polyester resin, polyamide resin, epoxy resin, phenolic resin, amino resin, polyether resin, polyester polyol and polyether polyol. Under the premise of ensuring excellent adhesion of the adhesive layer to the substrate layer, excellent adhesion to the metal aluminum plate and the flame retardant performance of the pressure insulation film, the overflow of the hot-pressed insulation film after hot pressing is effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of hot-pressed insulating films, and relates to a method for improving adhesive overflow in hot-pressed insulating films, as well as the hot-pressed insulating film, its preparation method, and its application method. Background Technology

[0002] The battery pack is the most crucial component of an electric vehicle, providing centralized protection and management of the battery pack, preventing water ingress and impact damage, and also offering insulation and flame retardancy. Currently, side panel insulation of the battery pack is achieved by hot-pressing a layer of insulating film onto an aluminum plate. This method boasts high bonding strength, excellent insulation, and a flame retardancy rating of VTM-0. The thermosetting resin adhesive in the hot-pressed insulating film cures rapidly under specific hot-pressing conditions. However, during the hot-pressing process, the resin adhesive in existing hot-pressed insulating films gradually seeps out and flows onto the surface of the battery side panel aluminum plate as the temperature and pressure gradually increase. This excess adhesive has strong bonding strength and is difficult to remove, and excessive excess adhesive directly affects product performance and appearance. Therefore, while ensuring the excellent performance of the hot-pressed insulating film, improving the treatment of excess adhesive is crucial. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a method for improving adhesive overflow in hot-pressed insulating films, as well as the hot-pressed insulating film itself, its preparation method, and its usage method. While ensuring excellent adhesion between the adhesive layer and the substrate layer, excellent adhesion to the aluminum plate, and the flame-retardant properties of the pressure-resistant insulating film, this invention effectively improves the adhesive overflow situation of the hot-pressed insulating film after hot pressing.

[0004] The object of the present invention is achieved by the following method: a method for improving adhesive overflow in a hot-pressed insulating film, the hot-pressed insulating film comprising a substrate layer and an adhesive layer formed on the substrate layer, wherein a resin rich in active functional groups is added to the adhesive layer, the resin rich in active functional groups being at least one selected from unsaturated polyester resin, polyamide resin, epoxy resin, phenolic resin, amino resin, polyether resin, polyester polyol, and polyether polyol.

[0005] A hot-pressed insulating film includes a substrate layer and an adhesive layer formed on the substrate layer. The adhesive layer is composed of the following raw materials: polyurethane resin, flame retardant, isocyanate curing agent, resin rich in active functional groups, and additives, in the following mass percentages: polyurethane resin 40-70 wt%, flame retardant 10-40 wt%, isocyanate curing agent 2-10 wt%, and additives 1-10 wt%. The resin rich in active functional groups is 0.2%-30% of the total mass of the polyurethane resin. The resin rich in active functional groups is at least one selected from unsaturated polyester resin, polyamide resin, epoxy resin, phenolic resin, amino resin, polyether resin, polyester polyol, and polyether polyol.

[0006] The additive is at least one of a leveling agent, a coupling agent, and a hydrolysis resistant agent.

[0007] Polyurethane resin can be one or a mixture of several of the following: single-component polyurethane resin, two-component polyurethane resin, and modified polyurethane resin.

[0008] The flame retardant is one or a mixture of several of the following: phosphorus-based flame retardants, nitrogen-based flame retardants, silicon-based flame retardants, metal hydroxide flame retardants, metal oxide flame retardants, and metal boride flame retardants.

[0009] The isocyanate curing agent is one or a mixture of several aromatic isocyanate curing agents, aliphatic isocyanate curing agents, and alicyclic isocyanate curing agents.

[0010] The thickness of the adhesive layer is 20-50 μm.

[0011] The thickness of the substrate layer is 80-120μm, and the raw material of the substrate layer includes a matrix resin, wherein the matrix resin is one or more of polyethylene terephthalate, polyetherimide, polyimide, polyamideimide or polyethylene naphthalate.

[0012] The preparation method of the hot-pressed insulating film includes the following steps: (1) adding polyurethane resin and resin rich in active functional groups to an organic solvent, stirring evenly, then adding flame retardant and additives, stirring evenly, and finally adding curing agent, stirring evenly to prepare an adhesive coating liquid; (2) coating the adhesive coating liquid onto the substrate layer, baking at 80℃-100℃ for 1-5 minutes, and then baking at 110℃-135℃ for 1-5 minutes to obtain the hot-pressed insulating film.

[0013] The side of the substrate layer coated with the adhesive liquid is pre-treated with corona.

[0014] The method of using the hot-pressed insulating film involves hot-pressing the adhesive layer of the hot-pressed insulating film onto an aluminum plate at a temperature of 150-180℃, a pressure of 0.5-3 MPa, and a time of 2-15 minutes.

[0015] Compared to existing technologies, the method for improving adhesive overflow in hot-pressed insulating films provided by this invention involves adding a resin rich in active functional groups to the coating liquid of the adhesive layer. This allows the resin to crosslink with the active groups of polyurethane resin and isocyanate, generating a polymer with a high degree of crosslinking. This increases the glass transition temperature of the adhesive layer. While ensuring excellent adhesion between the adhesive layer and the insulating substrate layer, excellent adhesion to metals, and the flame-retardant properties of the pressure-resistant insulating film, this method effectively improves the adhesive overflow situation of the hot-pressed insulating film after hot pressing and eliminates processing defects in the product. Detailed Implementation

[0016] A method for improving adhesive overflow in a hot-pressed insulating film, the hot-pressed insulating film comprising a substrate layer and an adhesive layer formed on the substrate layer, wherein a resin rich in active functional groups is added to the adhesive layer, the resin rich in active functional groups being at least one selected from unsaturated polyester resin, polyamide resin, epoxy resin, phenolic resin, amino resin, polyether resin, polyester polyol, and polyether polyol.

[0017] A hot-pressed insulating film includes a substrate layer and an adhesive layer formed on the substrate layer. The adhesive layer is composed of the following raw materials: polyurethane resin, flame retardant, isocyanate curing agent, resin rich in active functional groups, and additives, in the following mass percentages: polyurethane resin 40-70 wt%, flame retardant 10-40 wt%, isocyanate curing agent 2-10 wt%, and additives 1-10 wt%. The resin rich in active functional groups is 0.2%-30% of the total mass of the polyurethane resin. The resin rich in active functional groups is at least one selected from unsaturated polyester resin, polyamide resin, epoxy resin, phenolic resin, amino resin, polyether resin, polyester polyol, and polyether polyol.

[0018] The additive is at least one of a leveling agent, a coupling agent, and a hydrolysis resistant agent.

[0019] Polyurethane resin can be one or a mixture of several of the following: single-component polyurethane resin, two-component polyurethane resin, and modified polyurethane resin.

[0020] The flame retardant is one or a mixture of several of the following: phosphorus-based flame retardants, nitrogen-based flame retardants, silicon-based flame retardants, metal hydroxide flame retardants, metal oxide flame retardants, and metal boride flame retardants.

[0021] The isocyanate curing agent is one or a mixture of several aromatic isocyanate curing agents, aliphatic isocyanate curing agents, and alicyclic isocyanate curing agents.

[0022] The thickness of the adhesive layer is 20-50 μm.

[0023] The thickness of the substrate layer is 80-120μm, and the raw material of the substrate layer includes a matrix resin, wherein the matrix resin is one or more of polyethylene terephthalate, polyetherimide, polyimide, polyamideimide or polyethylene naphthalate.

[0024] The preparation method of the hot-pressed insulating film includes the following steps: (1) adding polyurethane resin and resin rich in active functional groups to an organic solvent, stirring evenly, then adding flame retardant and additives, stirring evenly, and finally adding curing agent, stirring evenly to prepare an adhesive coating liquid; (2) coating the adhesive coating liquid onto the substrate layer, baking at 80℃-100℃ for 1-5 minutes, and then baking at 110℃-135℃ for 1-5 minutes to obtain the hot-pressed insulating film.

[0025] The side of the substrate layer coated with the adhesive liquid is pre-treated with corona.

[0026] The method of using the hot-pressed insulating film involves hot-pressing the adhesive layer of the hot-pressed insulating film onto an aluminum plate at a temperature of 150-180℃, a pressure of 0.5-3 MPa, and a time of 2-15 minutes.

[0027] The present invention provides a method for improving adhesive overflow in hot-pressed insulating films by adding a resin rich in active functional groups to the coating liquid of the adhesive layer. This allows the resin to crosslink with the active groups of polyurethane resin and isocyanate, generating a polymer with a high degree of crosslinking. This increases the glass transition temperature of the adhesive layer. While ensuring excellent adhesion between the adhesive layer and the insulating substrate layer, excellent adhesion to metal, and the flame-retardant properties of the pressure-resistant insulating film, the method effectively improves the adhesive overflow of the hot-pressed insulating film after hot pressing and eliminates processing defects in the product.

[0028] The present invention will now be described in detail with reference to specific embodiments. It should be noted that these embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments based on the above description of the present invention.

[0029] Example 1 Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 57 parts; Methyl etherified amino resin: Resimene 717 / 1 part; Flame retardant: phosphonite flame retardant OP935 / 35 parts; Curing agent: N 75 MPA / X / 5 parts; Leveling agent: BYK-333 / 1 part; Silane coupling agent: KBM303 / 0.5 parts; Hydrolysis resistant agent: Polycarbodiimide V04 / 0.5 parts.

[0030] Preparation method of adhesive liquid: Polyurethane resin was pre-dissolved in methyl ethyl ketone (MEK) solvent, and then methylated amino resin was added and stirred at room temperature for 30 minutes. Subsequently, flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours, then filtered and ready for use.

[0031] Method for manufacturing hot-pressed insulating film: One side of a 97μm thick black PET film is pre-corona treated. Adhesive solution is applied to the corona-treated side of the PET film, and it is baked at 90℃ for 2 minutes and then at 130℃ for 2 minutes to produce a 35μm thick hot-pressed insulating film.

[0032] Hot pressing method for insulating film: Select an aluminum plate with dimensions of 250mm*200mm and a thickness of 0.3mm. Cut the hot-pressed insulating film into 6 pieces of 25mm*150mm. Arrange the 6 pieces of hot-pressed insulating film neatly on the aluminum plate. Adhesive layer is bonded to the surface of the aluminum plate. Hot-pressing conditions are 180℃ / 10min / 1Mpa.

[0033] Example 2 Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 48 parts; Epoxy resin: 1256 / 10 parts; Flame retardant: phosphonite flame retardant OP935 / 35 parts; Curing agent: N 75 MPA / X / 5 parts; Leveling agent: BYK-333 / 1 part; Silane coupling agent: KBM303 / 0.5 parts; Hydrolysis resistant agent: Polycarbodiimide V04 / 0.5 parts.

[0034] Preparation method of adhesive liquid: The epoxy resin was pre-dissolved in dimethylacetamide (DMAC) solvent, and polyurethane resin was added and stirred at room temperature for 30 minutes. Then, flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours. The mixture was then filtered and ready for use.

[0035] The method for manufacturing the hot-pressed insulating film is the same as in Example 1.

[0036] The hot pressing method for the insulating film is the same as in Example 1.

[0037] Example 3 Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 48 parts; Polycarbonate polyol: Nippollan 964 / 10 parts; Flame retardant: phosphonite flame retardant OP935 / 35 parts; Curing agent: N 75 MPA / X / 5 parts; Leveling agent: BYK-333 / 1 part; Silane coupling agent: KBM303 / 0.5 parts; Hydrolysis resistant agent: Polycarbodiimide V04 / 0.5 parts.

[0038] Preparation method of adhesive liquid: Polyurethane resin was pre-dissolved in methyl ethyl ketone (MEK) solvent, and polycarbonate polyol was added and stirred at room temperature for 30 minutes. Then flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours and then filtered for use.

[0039] The method for manufacturing the hot-pressed insulating film is the same as in Example 1.

[0040] The hot pressing method for the insulating film is the same as in Example 1.

[0041] Comparative Example Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 58 parts; Flame retardant: phosphonite flame retardant OP935 / 35 parts; Curing agent: N 75MPA / X / 5 parts; Leveling agent: BYK-333 / 1 part; Silane coupling agent: KBM303 / 0.5 parts; Hydrolysis resistant agent: polycarbodiimide V04 / 0.5 parts.

[0042] Preparation method of adhesive liquid: Polyurethane resin was pre-dissolved in methyl ethyl ketone (MEK) solvent and stirred at room temperature for 30 minutes. Then, flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours. The mixture was then filtered and ready for use.

[0043] The method for manufacturing the hot-pressed insulating film is the same as in Example 1.

[0044] The hot pressing method for the insulating film is the same as in Example 1.

[0045] The sources of raw materials in the examples and comparative examples are as follows: Resimene 717, a methylated amino resin, manufactured by INEOS, USA; MX-8347, polyurethane resin, Yantai Chemical; 1256, epoxy resin, Mitsubishi Chemical, Japan; Nippollan 964, polycarbonate polyol, Tosoh Corporation, Japan; N 75 MPA / X, curing agent, Dexmold OP935, phosphonite flame retardant, Clariant, Switzerland; BYK-333, leveling agent, BYK (Germany); V04, polycarbodiimide, Nisshinbo, Japan; KBM303, a silane coupling agent, manufactured by Shin-Etsu Chemical Co., Ltd., Japan.

[0046] The performance tests of the hot-pressed insulating films in the above embodiments and comparative examples are shown in Table 1.

[0047] Table 1 Evaluation method: Peel strength: The hot-pressed insulating film was laminated at a high temperature of 180℃ / 1Mpa / 10 minutes, then cooled to room temperature of 25℃ for 30 minutes. Six 25mm*150mm hot-pressed sheets were cut and the peel strength between the insulating film and the aluminum plate was tested at a 180° angle with a peel speed of 100mm / min. Sansi Zongheng Electronics UTM2503 universal testing machine was used.

[0048] Flame retardant performance: The coated hot-pressed insulating film is baked at 170℃ for 20 minutes, cooled to room temperature, and a sample with dimensions of 250mm (length) × 50mm (width) is prepared and subjected to combustion according to UL 94 standard. The flame retardant rating is then determined based on the standard.

[0049] Excess adhesive: After the hot-pressed insulating film is laminated at a high temperature of 180℃ / 1Mpa / 10 minutes and then restored to room temperature of 25℃ for 30 minutes, the width of the excess adhesive is measured in mm using a handheld 100x reading microscope.

[0050] The embodiments of the present invention may also be the following embodiments. Example 4 Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 70 parts; Methyl etherified amino resin: Resimene 717 / 2 parts; Flame retardant: phosphonite flame retardant OP935 / 10 parts; Curing agent: N 75 MPA / X / 8 parts; Leveling agent: BYK-333 / 6 parts; Silane coupling agent: KBM303 / 2 parts; Hydrolysis resistant agent: Polycarbodiimide V04 / 2 parts.

[0051] Preparation method of adhesive liquid: Polyurethane resin was pre-dissolved in methyl ethyl ketone (MEK) solvent, and then methylated amino resin was added and stirred at room temperature for 30 minutes. Subsequently, flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours, then filtered and ready for use.

[0052] The method for manufacturing the hot-pressed insulating film is the same as in Example 1.

[0053] The hot pressing method for the insulating film is the same as in Example 1.

[0054] Example 5 Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 40 parts; Epoxy resin: 1256 / 12 parts; Flame retardant: phosphonite flame retardant OP935 / 40 parts; Curing agent: N 75 MPA / X / 2 parts; Leveling agent: BYK-333 / 2 parts; Silane coupling agent: KBM303 / 2 parts; Hydrolysis resistant agent: Polycarbodiimide V04 / 2 parts.

[0055] Preparation method of adhesive liquid: The epoxy resin was pre-dissolved in dimethylacetamide (DMAC) solvent, and polyurethane resin was added and stirred at room temperature for 30 minutes. Then, flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours. The mixture was then filtered and ready for use.

[0056] The method for manufacturing the hot-pressed insulating film is the same as in Example 1.

[0057] The hot pressing method for the insulating film is the same as in Example 1.

[0058] Example 6 Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 50 parts; Methyl etherified amino resin: Resimene 717 / 1 part; Flame retardant: phosphonite flame retardant OP935 / 39 parts; Curing agent: N 75 MPA / X / 8 parts; Leveling agent: BYK-333 / 1 part; Silane coupling agent: KBM303 / 0.5 parts; Hydrolysis resistant agent: Polycarbodiimide V04 / 0.5 parts.

[0059] Preparation method of adhesive liquid: Polyurethane resin was pre-dissolved in methyl ethyl ketone (MEK) solvent, and then methylated amino resin was added and stirred at room temperature for 30 minutes. Subsequently, flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours, then filtered and ready for use.

[0060] The method for manufacturing the hot-pressed insulating film is the same as in Example 1.

[0061] The hot pressing method for the insulating film is the same as in Example 1.

[0062] Example 7 Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 60 parts; Epoxy resin: 1256 / 12 parts; Flame retardant: phosphonite flame retardant OP935 / 20 parts; Curing agent: N 75 MPA / X / 7 parts; Leveling agent: BYK-333 / 0.5 parts; Silane coupling agent: KBM303 / 0.25 parts; Hydrolysis resistant agent: Polycarbodiimide V04 / 0.25 parts.

[0063] Preparation method of adhesive liquid: The epoxy resin was pre-dissolved in dimethylacetamide (DMAC) solvent, and polyurethane resin was added and stirred at room temperature for 30 minutes. Then, flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours. The mixture was then filtered and ready for use.

[0064] The method for manufacturing the hot-pressed insulating film is the same as in Example 1.

[0065] The hot pressing method for the insulating film is the same as in Example 1.

[0066] Example 8 Raw materials for adhesive liquid: (All figures are in parts by weight) Polyurethane resin: MX-8347 / 65 parts; Polycarbonate polyol: Nippollan 964 / 10 parts; Flame retardant: phosphonite flame retardant OP935 / 13 parts; Curing agent: N 75 MPA / X / 10 parts; Leveling agent: BYK-333 / 1 part; Silane coupling agent: KBM303 / 0.5 parts; Hydrolysis resistant agent: Polycarbodiimide V04 / 0.5 parts.

[0067] Preparation method of adhesive liquid: Polyurethane resin was pre-dissolved in methyl ethyl ketone (MEK) solvent, and polycarbonate polyol was added and stirred at room temperature for 30 minutes. Then flame retardant, leveling agent, silane coupling agent and hydrolysis resistant agent were added and stirred for 30 minutes. Finally, isocyanate curing agent was added and stirred for 2 hours and then filtered for use.

[0068] The method for manufacturing the hot-pressed insulating film is the same as in Example 1.

[0069] The hot pressing method for the insulating film is the same as in Example 1.

[0070] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. It should be noted that for those skilled in the art and any person skilled in the art, any equivalent substitutions or changes made to the technical solution and inventive concept of the present invention without departing from the overall concept of the present invention, as well as any changes and improvements made, should also be considered within the scope of protection of the present invention.

Claims

1. A hot-pressed insulating film, characterized in that: The hot-pressed insulating film includes a substrate layer and an adhesive layer formed on the substrate layer. The adhesive layer is composed of the following raw materials: polyurethane resin, flame retardant, isocyanate curing agent, resin rich in active functional groups, and additives, in the following mass percentages: polyurethane resin 40-70 wt%, flame retardant 10-40 wt%, isocyanate curing agent 2-10 wt%, additives 1-10 wt%, and the resin rich in active functional groups is 0.2%-30% of the total mass of polyurethane resin; the resin rich in active functional groups is a methylated amino resin or a polycarbonate polyol. The preparation method of the hot-pressed insulating film is as follows: (1) Polyurethane resin and resin rich in active functional groups are added to an organic solvent and stirred evenly. Then flame retardant and additives are added and stirred evenly. Finally, curing agent is added and stirred evenly to prepare an adhesive coating liquid; (2) The adhesive coating liquid is coated on the substrate layer and baked at 80℃-100℃ for 1-5 minutes, and then baked at 110℃-135℃ for 1-5 minutes to obtain the hot-pressed insulating film. Resins rich in active functional groups crosslink with the active groups of polyurethane resin and isocyanate to generate polymers with a high degree of crosslinking, thereby increasing the glass transition temperature of the adhesive layer and effectively improving the overflow of adhesive in hot-pressed insulating films after hot pressing.

2. The hot-pressed insulating film according to claim 1, characterized in that: The additive is at least one of a leveling agent, a coupling agent, and a hydrolysis resistant agent.

3. The hot-pressed insulating film according to claim 1, characterized in that: Polyurethane resin is one or a mixture of several of the following: single-component polyurethane resin, two-component polyurethane resin, and modified polyurethane resin. The flame retardant is one or a mixture of several of the following: phosphorus-based flame retardants, nitrogen-based flame retardants, silicon-based flame retardants, metal hydroxide flame retardants, metal oxide flame retardants, and metal boride flame retardants. The isocyanate curing agent is one or a mixture of several aromatic isocyanate curing agents, aliphatic isocyanate curing agents, and alicyclic isocyanate curing agents.

4. The hot-pressed insulating film according to claim 1, characterized in that: The thickness of the adhesive layer is 20-50 μm.

5. The hot-pressed insulating film according to claim 1, characterized in that: The thickness of the substrate layer is 80-120μm, and the raw material of the substrate layer includes a matrix resin, wherein the matrix resin is one or more of polyethylene terephthalate, polyetherimide, polyimide, polyamideimide or polyethylene naphthalate.

6. The method for preparing a hot-pressed insulating film according to claim 1, characterized in that: (1) Add polyurethane resin and resin rich in active functional groups to an organic solvent, stir evenly, then add flame retardant and additives, stir evenly, and finally add curing agent, stir evenly to prepare adhesive coating liquid; (2) Coat the adhesive coating liquid onto the substrate layer, bake at 80℃-100℃ for 1-5 min, and then bake at 110℃-135℃ for 1-5 min to obtain the hot-pressed insulating film.

7. The method for preparing a hot-pressed insulating film according to claim 6, characterized in that: The side of the substrate layer coated with the adhesive liquid is pre-treated with corona.

8. The method of using the hot-pressed insulating film according to any one of claims 1-7, characterized in that: The adhesive layer of the hot-pressed insulating film is hot-pressed onto an aluminum plate at a temperature of 150-180°C, a pressure of 0.5-3 MPa, and a time of 2-15 minutes.

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