Flexible heating assembly for electronic component and preparation method of flexible heating assembly

Abstract

The invention relates to the technical field of thick film materials special for electronic elements, in particular to a flexible heating assembly for an electronic element and a preparation method of the flexible heating assembly. The fiber supporting structures are distributed in the macromolecular continuous phase structure in a strip-shaped manner; and a plurality of conductive particles, wherein the plurality of conductive particles are uniformly distributed in the polymer continuous phase structure. Wherein part of the fiber supporting structure is a porous structure, and the porous structure is filled with the conductive particles. The flexible heating assembly has high conductivity, can be driven to heat under low voltage, has excellent mechanical stability, can bear a certain degree of repeated stretching and bending, maintains the conductivity in a stable interval, accords with a calculation result of artificial intelligence multi-scale simulation, and is suitable for popularization and application. The problems of excellent mechanical reliability, interface stability and electric heating performance of the flexible heating assembly in the fields of intelligent wearable devices, automotive electronics and the like are solved.

Description

Technical Field

[0001] This invention relates to the field of thick and thin film materials for electronic components, and in particular to a flexible heating component for electronic components and its preparation method. Background Technology

[0002] With the rapid development of wearable devices, automotive electronic systems, smart textiles, and healthcare products, flexible heating films (modules) have become an important research direction in functional materials technology. These components need to maintain stable and reliable heating performance under dynamic conditions such as repeated bending and stretching, thus placing higher demands on the flexibility, electrical conductivity, and fatigue resistance of the materials.

[0003] Traditional heating films (components) typically use metal wires, metal films, or transparent oxide conductive layers such as indium tin oxide (ITO) and fluorine-doped tin oxide (FTO) as the heating medium. Although these materials have excellent conductivity, they are inherently brittle and have poor ductility. Under bending or tensile stress, they are prone to microcracks, which can lead to the destruction of conductive paths, a sharp increase in resistance, or even functional failure, making them unsuitable for the application requirements of flexible electronic devices.

[0004] To improve the reliability and applicability of flexible heating films (assemblies) for electronic components, various improvement schemes have emerged in existing technologies. For example, using silver nanowires (AgNW) to prepare transparent conductive films as heating layers can, to a certain extent, balance transparency and conductivity, achieving flexible transparent heating functionality. However, silver nanowires are expensive and suffer from problems such as easy oxidation and silver ion migration, affecting their long-term stability. Furthermore, the network structure formed by silver nanowires is prone to changes in node contact resistance during repeated bending, leading to uneven heating or even localized overheating, thus limiting its reliability in practical applications.

[0005] Another technical solution utilizes graphene or modified graphene powder dispersed in a resin system to form printable conductive ink, and then prepares conductive patterns through screen printing or inkjet printing processes. This method has the advantages of simple process and low cost, but problems such as the uniformity of dispersion of conductive fillers in the ink, the adhesion strength with the substrate, and the contact resistance between printed layers are still prominent, often leading to reduced heating efficiency, uneven temperature distribution, and affecting the overall performance of the component.

[0006] In addition, existing technologies have attempted to combine carbon-based conductive materials with conductive polymers or metal microparticles to construct composite material systems with better conductivity and stability. While such composite systems can improve resistance characteristics to some extent, due to the complex material composition and poor interfacial compatibility, problems such as weak interlayer adhesion, resistance drift over time, and easy peeling during long-term use may still exist.

[0007] It is evident that existing flexible heating films (assemblies) still have many shortcomings in terms of conductive layer structure design, material system selection, and fabrication process stability. In particular, they have not yet achieved an effective balance between cost and performance, particularly in terms of low-temperature processability, heating uniformity, resistance to repeated bending, and long-term reliability. Therefore, there is an urgent need to provide a flexible heating film (assembly) for electronic components with high conductivity, good adhesion, and excellent mechanical stability, as well as its fabrication method, to address the problems existing in the prior art.

[0008] In view of this, the present invention is proposed. Summary of the Invention

[0009] The purpose of this invention is to provide a flexible heating component for electronic components and its preparation method, which meets the requirements of fields such as smart wearable devices and automotive electronics for excellent mechanical reliability, interface stability and electrothermal performance of flexible heating components.

[0010] In a first aspect, the present invention provides a flexible heating component for electronic components, comprising: The continuous phase structure of the polymer serves as the basic phase. A fiber support structure, wherein the fiber support structure is distributed in a strip-like manner in the continuous polymer phase structure, is used to provide good mechanical strength; And multiple conductive particles, wherein the multiple conductive particles are uniformly distributed in the continuous phase structure of the polymer; Some of the fiber support structures are porous structures, and the porous structures are filled with the conductive particles.

[0011] The flexible heating component for electronic devices of the present invention includes a continuous polymer phase structure, a fiber support structure, and multiple conductive particles. The fiber support structure is distributed in a strip-like manner within the continuous polymer phase structure, and the conductive particles are uniformly distributed within the continuous polymer phase structure and fill the porous structures of a portion of the fiber support structure. The polymer material, as the continuous phase, encapsulates and fixes the fiber skeleton and conductive particles, providing a mild deformation environment and long-term reliable stability for the internal "fiber-conductive" composite structure. The fiber support structure, distributed in a strip-like manner within the continuous polymer phase structure, serves as the "skeleton" of the entire component. It not only prevents irreversible plastic deformation or tearing of the polymer matrix under stress but also effectively hinders, deflects, or terminates crack propagation paths, preventing them from penetrating the entire component. The conductive particles are filled into the pores of the fiber support structure by the continuous polymer phase and solidify to form a micro-anchoring structure in the shape of "rivets" or "roots". This provides good adhesion for the distribution of conductive particles on the fiber support structure. Even if the polymer matrix suffers minor fatigue damage under repeated bending, the regional conductive pathways fixed and protected by the fiber network can still remain relatively stable, significantly reducing resistance drift and local overheating caused by relative displacement or contact failure of conductive particles.

[0012] As a preferred embodiment of this technical solution, the material of the continuous polymer phase structure includes any one or more combinations of oil-based polyurethane resin, water-based polyurethane resin, polyester resin, water-based acrylic emulsion, and polyvinyl alcohol derivatives.

[0013] As a preferred embodiment of this technical solution, the material of the fiber support structure includes any one of polyethylene fiber, polypropylene fiber, polybutene fiber and polyvinyl terephthalate fiber, and the fiber support structure is interconnected in the form of woven, knitted or non-woven fabric. Preferably, in the fiber support structure, the diameter of the fiber is 0.5-30 μm.

[0014] Preferably, in some of the fiber support structures, the fibers are provided with a plurality of pores with a size of 0.1-20 μm, so that conductive particles uniformly distributed in the polymer continuous phase structure can fill the pores.

[0015] As a preferred embodiment of this technical solution, the conductive particles include any one or more combinations of metals, carbon black, graphite, carbon nanotubes, graphene nanosheets, and graphene composite metal nanoparticles.

[0016] As a preferred embodiment of this technical solution, the conductive particles used in this invention are any one or more of metals, carbon black, graphite, carbon nanotubes, and graphene nanosheets combined with graphene to form a composite metal nanoparticle structure. Metals, carbon black, graphite, carbon nanotubes, and graphene nanosheets possess electrical conductivity and exhibit both one-dimensional and three-dimensional appearance characteristics. They can interweave with two-dimensional graphene, forming a tightly connected network structure with the metal nanoparticles on the graphene surface as contact points.

[0017] As a preferred embodiment of this technical solution, the metal in the conductive particles of this invention includes silver-coated copper powder, silver powder, and copper powder, etc.

[0018] As a preferred embodiment of this technical solution, the surface of the graphene composite metal nanoparticles is coated with at least one type of nano-metal particle, and the particle size of the nano-metal particle is less than 20 nm.

[0019] When graphene has multiple nano-metal particles on its surface, these particles can act as protruding sites, isolating the graphene powder from each other and preventing agglomeration during application. Simultaneously, these nano-metal particles can also serve as contact points between materials, providing highly conductive contact sites while preventing graphene powder from clustering together. Furthermore, when combined with other materials, they can form effective low-resistance contact points, reducing contact resistance.

[0020] As a preferred embodiment of this technical solution, the nano-metal particles have at least one unsaturated d-orbital domain, which is coupled with the π electrons of graphene, so that the nano-metal particles are firmly anchored to the graphene surface and do not detach due to mechanical dispersion or stirring.

[0021] As a preferred embodiment of this technical solution, the nano-metal particles include any one or more combinations of gold, silver, copper, iron, cobalt, nickel, platinum, palladium, ruthenium, and iridium.

[0022] As a preferred embodiment of this technical solution, the graphene used in the graphene-metal composite nanoparticles is intrinsic graphene with a bulk density of 0.01-0.03 g / cm³. 3 The thickness is 0.34-5 nm, the sheet diameter is 1-50 μm, and the ratio of the 2D peak to the G peak in the Raman spectrum is I. 2D / I G Greater than 0.5, the ratio of D peak to G peak I D / I G The oxygen content of graphene is less than 3 wt%, which is less than 0.2. Graphene composite metal nanoparticles prepared using intrinsic graphene with the above parameters possess high electrical and thermal conductivity. This is because graphene has a complete crystal lattice with few defects. In contrast, graphene oxide or graphene oxide-reduction oxide has more crystal defects and impurities and does not possess these properties.

[0023] In a preferred embodiment of this technical solution, the graphene composite metal nanoparticles are interconnected by surface-composite metal nanoparticles as contact points. Alternatively, the graphene composite metal nanoparticles may be interconnected with other conductive particles in the continuous polymer phase structure via surface-composite metal nanoparticles as contact points.

[0024] In a preferred embodiment of this technical solution, the graphene composite metal nanoparticles contain metal nanoparticles accounting for 0.1wt%-10wt% of the graphene.

[0025] As a preferred embodiment of this technical solution, the surface sheet resistance of the flexible heating component for electronic components of the present invention is less than 5Ω / sq / mil.

[0026] As a preferred embodiment of this technical solution, the surface sheet resistance of the flexible heating component for electronic components of the present invention is less than 1Ω / sq / mil.

[0027] As a preferred embodiment of this technical solution, the sheet resistance of the flexible heating component for electronic components of the present invention increases by ≤25% when the elongation rate is ≥5%.

[0028] As a preferred embodiment of this technical solution, the sheet resistance of the flexible heating component for electronic components of the present invention increases by ≤60% when the elongation rate is ≥10%.

[0029] As a preferred embodiment of this technical solution, the sheet resistance of the flexible heating component for electronic components of the present invention increases by ≤100% when the elongation rate is ≥15%.

[0030] As a preferred embodiment of this technical solution, the sheet resistance of the flexible heating component for electronic components of the present invention increases by ≤150% when the elongation rate is ≥20%.

[0031] Secondly, the present invention also discloses a method for preparing the above-mentioned flexible heating component for electronic components, specifically including the following steps: S1. Preparation of graphene composite metal nanoparticles; S2. Graphene composite metal nanoparticles are uniformly dispersed in at least one solvent, and then at least one polymer resin is added and uniformly dispersed to obtain graphene conductive ink. S3. Print and coat graphene conductive ink onto at least one surface of the fiber support structure, so that the graphene conductive ink fills the pores of the porous fiber support structure to obtain a flexible conductive structure. S4. Remove the solvent from the flexible conductive structure by means of standing, air drying or heating, and then cure the resin by means of heating or ultraviolet irradiation to obtain a flexible heating component for electronic components.

[0032] In the flexible heating component for electronic devices of this invention, firstly, contact sites are formed by the nano-metal particles on the surface of graphene composite nano-metal particles, enhancing the conductive pathway connections between graphene particles or between graphene and other conductive particles, reducing contact resistance, and effectively lowering the sheet resistance of the graphene conductive coating to below 1Ω, far exceeding existing conductive carbon paste products on the market. Simultaneously, graphene conductive ink is printed onto the surface of a stretchable textile using elastic resins and other polymer resins. Through penetration, the graphene conductive ink adheres tightly to the textile fibers, combining the stretchability and bending resistance of the textile while maintaining the high conductivity of the graphene conductive coating. Therefore, the flexible heating component for electronic devices prepared by this invention can be applied to emerging fields such as wearable devices and automotive electronics, effectively broadening its application scope and demonstrating strong industrial applicability.

[0033] Preferably, in this technical solution, the surface tension of the solvent is between 30-60 mJ / m 2 The solvent's surface tension matches that of the graphene, achieving uniform dispersion.

[0034] Preferably, the solvent has a boiling point higher than 140°C.

[0035] As a preferred embodiment of this technical solution, the solvent includes any one or more combinations of terpineol, N-methylpyrrolidone, divalent esters and diethylene glycol ethyl ether acetate.

[0036] As a preferred embodiment of this technical solution, the graphene conductive ink further includes conductive particles selected from any one or a combination of metals, carbon black, graphite, carbon nanotubes, and nanographene sheets.

[0037] This invention uses graphene composite metal nanoparticles as the conductive host and constructs the densest continuous conductive network by utilizing the morphology and size of different conductive particles, achieving conductivity that surpasses that of traditional conductive carbon paste.

[0038] As a preferred embodiment of this technical solution, the printing coating includes any one of the processes of screen printing, gravure printing, and blade coating.

[0039] As a preferred embodiment of this technical solution, the printing and coating process is performed at least twice, with a curing treatment between each printing and coating process. The present invention does not strictly limit the specific conditions of the curing treatment; for example, it can be baked at 120-180℃ for 10-60 minutes.

[0040] It should be noted that this invention does not strictly limit the specific thickness of the printing coating; the thickness of conventional printing coatings can be referenced.

[0041] In a preferred embodiment of this technical solution, during the preparation of graphene composite metal nanoparticles, multiple nano-metal particles are formed on the surface of graphene powder. These nano-metal particles utilize the reducing properties of graphene itself to anchor specific nano-metal salts onto the graphene powder surface via a reduction reaction. This is because metal elements possess unsaturated d-orbitals, which can interact with the π-electron cloud on the graphene surface, thereby reducing and forming d-π bonds that anchor to the graphene surface.

[0042] As a preferred embodiment of this technical solution, the preparation of graphene composite metal nanoparticles of the present invention includes the following steps: Graphene powder with a bulk density of 0.01-0.03 g / cm³ was selected. 3 The thickness is 0.34-5 nm, the sheet diameter is 1-50 μm, and the ratio of the 2D peak to the G peak in the Raman spectrum is I. 2D / I G Greater than 0.5, the ratio of D peak to G peak I D / I G The oxygen content of graphene is less than 3 wt% (less than 0.2). Prepare a metal salt solution of a certain concentration, with a pH value between 6 and 9; Graphene powder was slowly added to the metal salt solution while stirring, and the water temperature was controlled at 45-60℃. The mixture was stirred continuously for 12-24 hours, then filtered and freeze-dried to obtain graphene composite nano-metal particles.

[0043] In this invention, the specific concentration of the metal salt solution is not strictly limited, with the aim of achieving uniform distribution and tight bonding of nano-metal particles on the graphene surface.

[0044] As a preferred embodiment of this technical solution, the preparation of the graphene conductive ink of the present invention includes the following steps: Select a suitable solvent, add a dispersant, and then add graphene composite metal nanoparticles, conductive particles (such as conductive carbon black, silver-coated copper powder, etc.) and polymer resins (such as oil-based polyurethane resin, water-based polyurethane resin, polyester resin, water-based acrylic emulsion and polyvinyl alcohol derivatives, etc.) during stirring. The above mixture is transferred to an emulsifier and mixed uniformly at 8000-10000 rpm for 20-60 hours to obtain graphene conductive ink.

[0045] In this invention, the order of addition of graphene composite metal nanoparticles, conductive particles and polymer resin is not strictly limited, and can be adjusted according to the different viscosity conditions of the resin.

[0046] As a preferred embodiment of this technical solution, the dispersant used in the preparation process of graphene conductive ink includes any one or more combinations of polyvinyl alcohol and carboxymethyl cellulose.

[0047] The core of this invention lies in the setting and distribution of conductive particles in the flexible heating component of electronic components. Therefore, this invention does not strictly limit the amount of solvents, dispersants, polymer resins, graphene composite metal nanoparticles, conductive particles, etc. involved in the preparation process. The specific amount of graphene composite metal nanoparticles and conductive particles is based on providing the required conductivity, the specific amount of polymer resin is based on providing stable mechanical properties, and the specific amount of solvents and dispersants is based on achieving uniform dispersion of graphene composite metal nanoparticles and polymer resin.

[0048] For example, the graphene composite nano-metal particle conductive ink of the present invention comprises the following raw materials in parts by weight: 1-20 parts of graphene composite metal nanoparticles, 10-30 parts of polymer resin and 20-70 parts of dispersion medium (solvent and dispersant).

[0049] Preferably, the graphene composite nano-metal particle conductive ink of the present invention further includes 5-60 parts of other conductive particles besides graphene composite metal nanoparticles.

[0050] Finally, this invention also utilized artificial intelligence multi-scale simulation to conduct relevant experiments and theoretical verifications. Combining theory and empirical evidence, the reliability of the data in this invention was further confirmed.

[0051] Thirdly, the flexible heating component for electronic components of the present invention is applied in the fields of wearable devices, automotive electronic systems, smart textiles and healthcare products.

[0052] The flexible heating component for electronic devices of the present invention has at least the following beneficial effects: The flexible heating component for electronic devices of the present invention includes a continuous polymer phase structure, a fiber support structure, and multiple conductive particles. The fiber support structure is distributed in a strip-like manner within the continuous polymer phase structure, and the conductive particles are uniformly distributed within the continuous polymer phase structure and fill the porous structure of a portion of the fiber support structure. First, the polymer material, as the continuous phase, encapsulates and fixes the fiber skeleton and conductive particles. On the one hand, it isolates the internal conductive network and fibers, preventing them from being corroded by moisture and oxygen, thus improving long-term reliability. On the other hand, the soft polymer matrix itself can absorb and disperse some strain energy, providing a mild deformation environment for the internal "fiber-conductive" composite structure. Second, the fiber support structure, distributed in a strip-like manner within the continuous polymer phase structure, serves as the "skeleton" of the entire component. On the one hand, it can withstand the main load, preventing irreversible plastic deformation or tearing of the polymer matrix under stress. On the other hand, when the component is bent or stretched, the fibers can effectively hinder, deflect, or terminate the propagation path of cracks, preventing them from penetrating the entire component, thereby avoiding large-area breakage of the conductive pathway. Finally, conductive particles fill the fiber support structure and solidify to form a micro-anchoring structure resembling "rivets" or "tree roots." On the one hand, this provides a physical bonding force far exceeding van der Waals forces, which is the fundamental reason for achieving "good adhesion." On the other hand, since the conductive layer and the fiber layer are inter-embedded and integrated at the microscale, stress can be smoothly transmitted at the interface when the component deforms, avoiding stress concentration and interlayer delamination that are very likely to occur at the clear interface between the rigid conductive layer and the flexible matrix. In addition, the conductive particles are "locked" in the pores of the fiber skeleton by the continuous polymer phase. Even if the polymer matrix suffers minor fatigue damage under repeated bending, the regional conductive pathways fixed and protected by the fiber network can still remain relatively stable, thereby significantly reducing resistance drift and local overheating caused by the relative displacement or contact failure of conductive particles.

[0053] The flexible heating component of this invention has high conductivity, can drive heating under low voltage, and has excellent mechanical stability. It can withstand a certain degree of repeated stretching and bending, and maintains conductivity within a stable range. This solves the requirements of smart wearable devices and automotive electronics for excellent mechanical reliability, interface stability and electrothermal performance of flexible heating components. Attached Figure Description

[0054] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0055] Figure 1This is a SEM image of the graphene composite nanoparticles prepared in Example 1 of the present invention. Figure 2 This is a schematic diagram of the structure of the flexible heating component for electronic components of the present invention; Figure 3 This is a flowchart of the preparation method of the flexible heating component for electronic components of the present invention. Detailed Implementation

[0056] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0057] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form includes the plural form unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this description, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0058] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. 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.

[0059] Example 1 The preparation method of graphene composite metal nanoparticles includes the following steps: S1. Select graphene powder with a bulk density of 0.018 g / cm³. 3 The thickness is 1.5 nm, the average sheet diameter is 9 μm, and the ratio of the 2D peak to the G peak in the Raman spectrum is I. 2D / I G The ratio of peak D to peak G is 0.55. D / I G The value is 0.12, and the oxygen content is 1 wt%; S2. Prepare a 1M copper sulfate aqueous solution with a pH of 9. S3. Graphene powder is slowly added to the aqueous solution while stirring, and the water temperature is controlled at 45-60℃. Stirring is continued for 12-24 hours, then filtered and freeze-dried to obtain graphene composite nano-metal particles.

[0060] Figure 1This is a SEM image of the graphene composite nanoparticles prepared in this embodiment.

[0061] Example 2 The preparation method of graphene conductive ink includes the following steps: S1. Take N-methylpyrrolidone, add dispersant, and then add 10 parts of graphene composite metal nanoparticles prepared in Example 1, 6 parts of conductive carbon black and 20 parts of polyurethane resin during stirring. S2. Transfer the above mixture to an emulsifier and mix it evenly at 8000 rpm for 48 hours to obtain graphene conductive ink.

[0062] Example 3 The preparation method of graphene conductive ink includes the following steps: S1. Take a divalent ester solvent (a mixture of adipic acid, glutaric acid and succinic acid), add a dispersant, and then add 10 parts of graphene composite metal nanoparticles prepared in Experiment Example 1, 6 parts of silver-coated copper powder with an average particle size of 3 μm and 20 parts of polyurethane resin during stirring. S2. Transfer the above mixture to an emulsifier and mix it evenly at 8000 rpm for 20 hours to obtain graphene conductive ink.

[0063] Example 4 like Figure 3 As shown, the method for fabricating a flexible heating component for electronic devices includes the following steps: A nonwoven fabric was used as a substrate, and the graphene conductive ink prepared in Example 2 was printed and coated onto the surface of the nonwoven fabric substrate using a 150-mesh screen printing plate. The substrate was then placed in an oven and baked at 150°C for 30 minutes to obtain a flexible heating component for electronic components.

[0064] The sheet resistance of the flexible heating element obtained in this embodiment is 15Ω / sq. After being bent by a fixture with a bending radius of 0.5mm, no cracks appeared on the surface of the flexible heating element, and the sheet resistance value was 15.8Ω / sq.

[0065] The flexible heating component obtained in this embodiment has a sheet resistance of 18.1 Ω / sq when the elongation is 5%; it increases to 22.9 Ω / sq when the elongation is 10%; it increases to 28.5 Ω / sq when the elongation is 15%; and it increases to 36 Ω / sq when the elongation is 20%.

[0066] Figure 2 This is a schematic diagram of the structure of the flexible heating component for electronic components prepared in this embodiment.

[0067] Example 5 like Figure 3 As shown, the method for fabricating a flexible heating component for electronic devices includes the following steps: Take a non-woven fabric as a substrate, and use a 150-mesh screen printing plate to print and coat the graphene conductive ink prepared in Example 2 onto the surface of the non-woven fabric substrate. Place it in an oven and bake at 150°C for 30 minutes. Repeat the aforementioned screen printing steps to obtain a flexible heating component for electronic components.

[0068] The sheet resistance of the flexible heating element obtained in this embodiment is 7Ω / sq. After being bent by a fixture with a bending radius of 0.5mm, no cracks appeared on the surface of the flexible heating element, and the sheet resistance value was 7.5Ω / sq.

[0069] The flexible heating component obtained in this embodiment has a sheet resistance of 8.2 Ω / sq when the elongation is 5%; it increases to 10.8 Ω / sq when the elongation is 10%; it increases to 13.5 Ω / sq when the elongation is 15%; and it increases to 16.7 Ω / sq when the elongation is 20%.

[0070] Example 6 like Figure 3 As shown, the method for fabricating a flexible heating component for electronic devices includes the following steps: Using a woven fabric as a substrate, the graphene conductive ink prepared in Experiment 3 was screen-printed onto the surface of the woven fabric substrate using an 80-mesh screen printing plate. The substrate was then placed in an oven and baked at 150°C for 30 minutes to obtain a flexible heating component for electronic components.

[0071] The sheet resistance of the flexible heating element obtained in this embodiment is 0.7Ω / sq. After being bent by a fixture with a bending radius of 0.5mm, no cracks appeared on the surface of the flexible heating element, and the sheet resistance value was 0.7Ω / sq.

[0072] The flexible heating component obtained in this embodiment has a sheet resistance of 0.75 Ω / sq when the elongation is 5%; its sheet resistance increases to 0.9 Ω / sq when the elongation is 10%; its sheet resistance increases to 1.2 Ω / sq when the elongation is 15%; and its sheet resistance increases to 1.6 Ω / sq when the elongation is 20%.

[0073] Experimental Example 7 like Figure 3 As shown, the method for fabricating a flexible heating component for electronic devices includes the following steps: Take a woven fabric as the substrate, and use an 80-mesh screen printing plate to screen print the graphene conductive ink prepared in Experiment 3 onto the surface of the woven fabric substrate. Place it in an oven and bake at 150°C for 30 minutes. Repeat the aforementioned screen printing steps to obtain a flexible heating component for electronic components.

[0074] The sheet resistance of the flexible heating element obtained in this embodiment is 0.3Ω / sq. After being bent by a fixture with a bending radius of 0.5mm, no cracks appeared on the surface of the flexible heating element, and the sheet resistance value was 0.3Ω / sq.

[0075] The flexible heating component obtained in this embodiment has a sheet resistance of 0.35 Ω / sq when the elongation is 5%; its sheet resistance increases to 0.4 Ω / sq when the elongation is 10%; its sheet resistance increases to 0.5 Ω / sq when the elongation is 15%; and its sheet resistance increases to 0.7 Ω / sq when the elongation is 20%.

[0076] Compare with Example 1 In this comparative example, the preparation methods of graphene composite metal nanoparticles, graphene conductive ink, and flexible heating components for electronic devices are basically the same as those in Examples 1, 2, and 4, respectively. The difference lies in that the graphene powder used in the preparation of graphene composite metal nanoparticles is graphene prepared by the redox method, and the bulk density of this graphene powder is 0.01 g / cm³. 3 The thickness is 1 nm, the average sheet diameter is 1-2 μm, and the ratio of the 2D peak to the G peak in the Raman spectrum is I. 2D / I G The ratio of peak D to peak G is 0.34. D / I G The value is 1.1, and the oxygen content is 20 wt%.

[0077] Compare with Example 2 In this comparative example, the preparation methods of graphene composite metal nanoparticles, graphene conductive ink, and flexible heating components for electronic devices are basically the same as those in Examples 1, 2, and 4, respectively. The difference is that in the preparation of graphene composite metal nanoparticles, epoxy resin is used instead of polyurethane resin.

[0078] Compare with Example 3 In this comparative example, the preparation methods of graphene composite metal nanoparticles, graphene conductive ink, and flexible heating components for electronic devices are basically the same as those in Examples 1, 2, and 4, respectively. The difference is that in the preparation of the flexible heating components for electronic devices, the graphene ink is coated on the surface of a woven fabric without a porous structure.

[0079] To investigate the mechanical reliability, interface stability, and electrothermal performance of the prepared flexible heating components, the present invention conducted bending tests (bending with a fixture with a bending radius of 0.5 mm), tensile tests, and sheet resistance tests on the flexible heating components prepared in Examples 4-7 and Comparative Examples 1-3. The test results are shown in Table 1.

[0080] Table 1 Test Results

[0081] As shown in Table 1, the flexible heating components for electronic devices prepared in Examples 4-7 of this invention exhibit a resistance change rate of <7% after bending with an extremely small radius of 0.5 mm, and no surface cracks, indicating excellent bending fatigue resistance and interfacial bonding strength, making them suitable for repeated bending scenarios. Under 20% tensile strain, the resistance gradually increases to a maximum of 36 Ω / sq, while the device maintains complete conductivity, demonstrating good stretchability and dynamic reliability, meeting the deformation requirements of human movement or elastic substrates. The maximum initial low sheet resistance is 15 Ω / sq, ensuring high thermal efficiency. Therefore, the flexible heating components prepared by this invention possess excellent mechanical reliability, interfacial stability, and electrothermal performance.

[0082] In Comparative Example 1, graphene prepared by the redox method was used as a raw material to prepare a flexible heating component. The resulting flexible heating component had poor conductivity. This may be because the oxygen content of the redox graphene is extremely high, and there are still a large number of defects and impurities, which affect the conductivity.

[0083] In Comparative Example 2, epoxy resin was used instead of polyurethane resin in the preparation of graphene composite metal nanoparticles. Because epoxy resin is more rigid, the coating is brittle, resulting in the flexible heating component that basically does not have bending and stretching properties.

[0084] In contrast to Example 3, in the preparation of the flexible heating component for electronic components, the woven fabric used does not have a porous structure on its surface and its tensile strength is not as good as that of the non-woven fabric (which has more pores and therefore better tensile strength). As a result, the conductive particles cannot be effectively "locked" in the pores of the fiber skeleton, and therefore the resulting flexible heating component has poor stability.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A flexible heat generating component for electronic components, characterized by comprising: include: Continuous phase structure of polymers; A fiber support structure, wherein the fiber support structure is distributed in a strip-like manner in the continuous polymer phase structure; And multiple conductive particles, wherein the multiple conductive particles are uniformly distributed in the continuous phase structure of the polymer; Some of the fiber support structures are porous structures, and the porous structures are filled with the conductive particles.

2. The flexible heating assembly for electronic components according to claim 1, wherein The materials of the continuous phase polymer structure include any one or more combinations of oil-based polyurethane resin, water-based polyurethane resin, polyester resin, water-based acrylic emulsion, and polyvinyl alcohol derivatives.

3. The flexible heating assembly for electronic components according to claim 1, wherein The fiber support structure is made of any one of polyethylene fiber, polypropylene fiber, polybutene fiber, and polyvinyl terephthalate fiber, and the fiber support structure is interconnected in the form of woven, knitted, or nonwoven fabric. Preferably, in the fiber support structure, the diameter of the fibers is 0.5-30 μm; Preferably, in some of the fiber support structures, the fibers are provided with a plurality of pores with a size of 0.1-20μm.

4. The flexible heating assembly for electronic components according to claim 1, wherein The conductive particles include any one or more combinations of metals, carbon black, graphite, carbon nanotubes, graphene nanosheets, and graphene composite metal nanoparticles.

5. The flexible heating assembly for electronic components according to claim 4, wherein The surface of the graphene composite metal nanoparticles is coated with at least one type of metal nanoparticle, and the particle size of the metal nanoparticles is less than 20 nm.

6. The flexible heating assembly for electronic components according to claim 4, wherein The nano-metal particles have at least one unsaturated d-orbital domain, which is coupled with the π electrons of graphene. Preferably, the nano-metal particles include any one or more combinations of gold, silver, copper, iron, cobalt, nickel, platinum, palladium, ruthenium, and iridium.

7. The flexible heating assembly for electronic components according to claim 4, wherein The graphene composite metal nanoparticles are interconnected by surface-composite metal nanoparticles as contact points. Alternatively, the graphene composite metal nanoparticles may be interconnected with other conductive particles in the continuous polymer phase structure via surface-composite metal nanoparticles as contact points.

8. The flexible heating assembly for electronic components according to claim 4, wherein In the graphene-metal composite nanoparticles, the nano-metal particles account for 0.1wt%-10wt% of the graphene.

9. A method for producing a flexible heat generating member for an electronic component, characterized by, Includes the following steps: S1. Preparation of graphene composite metal nanoparticles; S2. Graphene composite metal nanoparticles are uniformly dispersed in at least one solvent, and then at least one polymer resin is added and uniformly dispersed to obtain graphene conductive ink. S3. Print and coat graphene conductive ink onto at least one surface of the fiber support structure to obtain a flexible conductive structure. S4. Remove the solvent from the flexible conductive structure, and then cure the resin by heating or ultraviolet irradiation to obtain a flexible heating component for electronic components. Preferably, the preparation method of the graphene composite metal nanoparticles includes the following steps: Graphene powder was selected; Prepare a metal salt solution with a pH value between 6 and 9; The metal salt solution was slowly added to the graphene powder while stirring. After continuous stirring, the mixture was filtered and freeze-dried to obtain graphene composite nano-metal particles. Preferably, the graphene is intrinsic graphene.

10. The method for preparing a flexible heating component for electronic components according to claim 9, characterized in that, The surface tension of the solvent is between 30-60 mJ / m 2 and the boiling point is higher than 140°C.

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