Tensile type TPU hot melt adhesive film

Abstract

The utility model relates to a kind of tensile TPU hot melt adhesive film, belong to TPU hot melt adhesive film technical field, including high-temperature-resistant buffer layer, the top of high-temperature-resistant buffer layer is provided with TPU base material layer, the top of TPU base material layer is provided with three-dimensional fiber reinforced layer, the top of three-dimensional fiber reinforced layer is provided with conductive function layer, the top of conductive function layer is provided with TPU hot melt layer, high-temperature-resistant buffer layer and TPU base material layer are formed mechanical lock connection by melting penetration.The tensile TPU hot melt adhesive film, high-temperature-resistant buffer layer and TPU base material layer are formed mechanical lock connection by melting penetration, compared with simple bonding, with higher connection strength and stability, can effectively resist interlayer separation under external force, three-dimensional fiber reinforced layer adopts wave-shaped grid-like fiber mesh structure, when being stretched by external force, fiber can disperse stress by its own deformation and mutual pull.

Description

Technical Field

[0001] This utility model relates to the field of TPU hot melt adhesive film technology, specifically a tensile-resistant TPU hot melt adhesive film. Background Technology

[0002] In today's industrial production and daily life, hot melt adhesive film is an important bonding material widely used in many industries such as electronics, automobiles, textiles, and packaging. Traditional hot melt adhesive films are mainly made of materials such as polyethylene and polyamide. These materials can meet basic bonding requirements to a certain extent, but in some special application scenarios with higher performance requirements, they have gradually revealed many limitations.

[0003] In the field of electronic device manufacturing, such as the assembly of flexible displays, hot melt adhesive films need to withstand the complex stresses generated during bending and folding operations. Traditional hot melt adhesive films, due to their poor tensile strength, are prone to problems such as separation of the adhesive layer from the bonded object and internal cracking of the adhesive layer when subjected to significant external stretching, leading to adhesion failure of the display and affecting the normal use and reliability of electronic devices. In automotive interior bonding, the vibrations and bumps generated during vehicle operation also apply tensile stress to the hot melt adhesive film. If the film's tensile strength is poor, interior parts are prone to detachment, threatening driving safety. Therefore, a tensile-resistant TPU hot melt adhesive film is proposed to solve the above problems. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides a tensile-resistant TPU hot melt adhesive film, which possesses advantages such as tensile strength and solves the problems mentioned in the background section.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A tensile-resistant TPU hot melt adhesive film includes a high-temperature resistant buffer layer, a TPU substrate layer on top of the high-temperature resistant buffer layer, a three-dimensional fiber reinforcement layer on top of the TPU substrate layer, a conductive functional layer on top of the three-dimensional fiber reinforcement layer, and a TPU hot melt layer on top of the conductive functional layer.

[0006] Furthermore, the high-temperature resistant buffer layer and the TPU substrate layer are mechanically interlocked through melt penetration.

[0007] Furthermore, the three-dimensional fiber reinforcement layer is a wavy mesh fiber network with a mesh density of ten to thirty fibers per centimeter.

[0008] Furthermore, the TPU hot melt layer is a low melting point TPU with a melting point between 80 and 110 degrees Celsius and a thickness of 0.05 to 0.15 millimeters.

[0009] Furthermore, the surface of the TPU hot melt layer is dispersed with micron-sized adhesive particles, and the adhesive particles are silicon dioxide modified with a silane coupling agent.

[0010] Furthermore, the top of the TPU hot melt layer is covered with a self-healing layer, and the inner side of the self-healing layer is provided with a number of microcapsules filled with repair agent.

[0011] Furthermore, the high-temperature resistant buffer layer is a polyimide microporous membrane with a thickness of 0.02 mm to 0.05 mm.

[0012] Compared with the prior art, this utility model provides a tensile-resistant TPU hot melt adhesive film, which has the following beneficial effects: This tensile-resistant TPU hot melt adhesive film features a high-temperature resistant buffer layer that is mechanically bonded to the TPU substrate layer through melt penetration. Compared to simple bonding, this connection method offers higher strength and stability, effectively resisting interlayer separation under external forces. The three-dimensional fiber reinforcement layer employs a wavy mesh fiber network structure. When subjected to external tension, the fibers can disperse stress through their own deformation and mutual pulling. The wavy structure increases the deformation space of the fibers, making them less prone to breakage under stress. Simultaneously, the mesh layout allows stress to propagate evenly throughout the fiber network. When the TPU hot melt adhesive film is subjected to external tension, the layers work together to resist tensile deformation, significantly enhancing the film's tensile strength and meeting the high tensile performance requirements of hot melt adhesive films in industries such as electronics and automotive. Attached Figure Description

[0013] Figure 1 This is a cross-sectional view of the structure of this utility model; Figure 2 This is a three-dimensional view of the structure of this utility model.

[0014] In the diagram: 1. High-temperature resistant buffer layer; 2. TPU substrate layer; 3. Three-dimensional fiber reinforcement layer; 4. Conductive functional layer; 5. TPU hot melt layer; 6. Self-healing layer. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] Please see Figures 1 to 2In this embodiment, a tensile-resistant TPU hot melt adhesive film includes a high-temperature resistant buffer layer 1, a TPU substrate layer 2 on top of the high-temperature resistant buffer layer 1, a three-dimensional fiber reinforcement layer 3 on top of the TPU substrate layer 2, a conductive functional layer 4 on top of the three-dimensional fiber reinforcement layer 3, and a TPU hot melt layer 5 on top of the conductive functional layer 4.

[0017] Specifically, the high-temperature resistant buffer layer 1 is a polyimide microporous membrane with a thickness of 0.02 mm to 0.05 mm. The high-temperature resistant buffer layer 1 and the TPU substrate layer 2 are mechanically locked together through melt penetration.

[0018] It should be noted that during the preparation process, the high-temperature resistant buffer layer 1 and the TPU substrate layer 2 are placed in a specific high-temperature environment, causing part of the TPU substrate layer 2 to reach a molten state. Due to the unique microporous structure of the polyimide microporous membrane, the molten TPU material permeates into these micropores. When the temperature decreases, the molten TPU material solidifies, forming a mechanically interlocking structure between the high-temperature resistant buffer layer 1 and the TPU substrate layer 2. Compared to simple bonding, this connection method has higher bonding strength and stability, effectively resisting interlayer separation under external forces, thereby enhancing the tensile strength of the entire TPU hot melt adhesive film.

[0019] Specifically, the three-dimensional fiber reinforcement layer 3 is a wavy mesh fiber network with a mesh density of ten to thirty fibers per centimeter.

[0020] It should be noted that the three-dimensional fiber reinforcement layer 3 adopts a wavy mesh fiber web structure. When subjected to external tensile force, this special-shaped fiber web can disperse stress through fiber deformation and mutual tension. The wavy structure increases the deformation space of the fibers, making them less prone to breakage during stress.

[0021] Specifically, the TPU hot melt layer 5 is made of low-melting-point TPU with a melting point between 80 and 110 degrees Celsius and a thickness of 0.05 to 0.15 millimeters.

[0022] It should be noted that the TPU hot melt layer 5 uses low-melting-point TPU material, with its melting point controlled between 80 and 110 degrees Celsius. This is to meet the bonding requirements of different application scenarios. When bonding to some temperature-sensitive substrates, the lower melting point can prevent high temperatures from damaging the substrate. At the same time, this temperature range also ensures that the TPU hot melt layer 5 maintains stable performance under normal operating conditions. The design with a thickness of 0.05 to 0.15 mm provides sufficient hot melt material to achieve a good bonding effect without increasing the overall weight and cost of the adhesive film due to excessive thickness. It also facilitates heat transfer, making the hot melt process more uniform and rapid, which helps to improve the tensile strength and bonding reliability of the adhesive film.

[0023] Specifically, the surface of the TPU hot melt layer 5 is dispersed with micron-sized adhesive particles, and the adhesive particles are silica modified with silane coupling agent.

[0024] It should be noted that silane coupling agents possess a unique chemical structure. One end can react chemically with the silica surface to form stable chemical bonds; the other end exhibits good compatibility and interaction with the TPU material. When the TPU hot melt layer 5 comes into contact with the bonded object, the adhesion-enhancing particles increase the contact area and friction between the adhesive layer and the bonded object. Simultaneously, the chemical action of the silane coupling agent promotes chemical bonding between the adhesive layer and the bonded object, thereby improving the bond strength. Under tensile stress, this enhanced adhesion effectively resists separation between the adhesive layer and the bonded object, enhancing the tensile strength of the entire bonded structure.

[0025] Specifically, the top of the TPU hot melt layer 5 is covered with a self-healing layer 6, and the inner side of the self-healing layer 6 is provided with a number of microcapsules filled with repair agent.

[0026] It should be noted that when the TPU hot melt adhesive film is subjected to external force during use and develops microcracks, the cracks will propagate and penetrate the self-healing layer 6, causing the microcapsules to rupture. The repair agent inside the microcapsules will be rapidly released and fill the cracks.

[0027] The working principle of the above embodiments is as follows: When the TPU hot melt adhesive film is stretched by an external force, the force is first applied to the TPU hot melt layer 5. Because the surface of the TPU hot melt layer 5 is dispersed with silica adhesive particles modified with silane coupling agent, these adhesive particles increase the friction and chemical bonding between the adhesive layer and adjacent layers, so that the external force can be more evenly distributed during the transmission process, avoiding premature damage to the adhesive layer caused by local stress concentration; As the external force continues to be transmitted, the TPU hot melt layer 5 transfers the stress to the three-dimensional fiber reinforcement layer 3. The wavy mesh fiber network structure of the three-dimensional fiber reinforcement layer 3 begins to play its role. The fibers disperse the stress through their own deformation and mutual tension. The wavy structure provides the fibers with a larger deformation space, allowing the fibers to stretch to a certain extent without breaking. At the same time, the mesh layout allows the stress to be evenly distributed throughout the fiber network, further enhancing the film's ability to resist external tensile forces. The three-dimensional fiber reinforcement layer 3 transfers the dispersed stress to the TPU substrate layer 2. The TPU substrate layer 2 and the high-temperature buffer layer 1 begin to bear the stress through a mechanically interlocked connection structure formed by melt penetration. This mechanical interlocking structure makes the two layers tightly bonded and can work together to resist tensile deformation when subjected to external force. The polyimide microporous membrane structure of the high-temperature buffer layer 1 can also absorb some of the stress, play a buffering role, and reduce the impact of stress on the overall film.

[0028] The installation, connection, or setting methods disclosed in this embodiment are all common mechanical connection methods, and any method that can achieve its beneficial effects can be implemented.

[0029] It should be noted that the orientations or positional relationships indicated herein are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the purpose of facilitating the description of this application and simplifying the description, and are not intended to 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 application.

[0030] 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 a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0031] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A tensile-resistant TPU hot melt adhesive film, characterized in that, It includes a high-temperature resistant buffer layer (1), a TPU substrate layer (2) is provided on the top of the high-temperature resistant buffer layer (1), a three-dimensional fiber reinforcement layer (3) is provided on the top of the TPU substrate layer (2), a conductive functional layer (4) is provided on the top of the three-dimensional fiber reinforcement layer (3), and a TPU hot melt layer (5) is provided on the top of the conductive functional layer (4). The high-temperature resistant buffer layer (1) and the TPU substrate layer (2) are mechanically locked together through melt penetration.

2. The tensile-resistant TPU hot melt adhesive film according to claim 1, characterized in that: The three-dimensional fiber reinforcement layer (3) is a wavy mesh fiber network with a mesh density of ten to thirty fibers per centimeter.

3. The tensile-resistant TPU hot melt adhesive film according to claim 1, characterized in that: The TPU hot melt layer (5) is a low melting point TPU with a melting point between 80 and 110 degrees Celsius and a thickness of 0.05 to 0.15 millimeters.

4. The tensile-resistant TPU hot melt adhesive film according to claim 1, characterized in that: The TPU hot melt layer (5) has micron-sized adhesive particles dispersed on its surface, and the adhesive particles are silicon dioxide modified with silane coupling agent.

5. The tensile-resistant TPU hot melt adhesive film according to claim 1, characterized in that: The top of the TPU hot melt layer (5) is covered with a self-healing layer (6), and the inner side of the self-healing layer (6) is provided with a number of microcapsules filled with repair agent.

6. The tensile-resistant TPU hot melt adhesive film according to claim 1, characterized in that: The high-temperature resistant buffer layer (1) is a polyimide microporous membrane with a thickness of 0.02 mm to 0.05 mm.

Images