Heating film for demisting and defrosting of automobile
By combining a transparent heating film with a conductive strip, and using semiconductor materials and a transparent adhesive layer, the problem of large space occupation and slow heating speed of automotive rearview mirror heating structures is solved, achieving rapid and uniform heating, and energy-saving and environmentally friendly defogging and defrosting effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUIZHOU KINGBALI TECH
- Filing Date
- 2025-05-23
- Publication Date
- 2026-05-19
AI Technical Summary
Existing automotive rearview mirror heating structures occupy a large space, have a slow heating speed, low energy efficiency, and poor defrosting and defogging effects.
The design combines a transparent electrothermal film with a conductive strip. The transparent electrothermal film achieves rapid heating by being uniformly covered on a transparent substrate. The conductive strip is placed at the bending part of the substrate to improve mechanical strength and aesthetics. Semiconductor materials such as antimony-doped tin oxide are used for heating, and the transparent adhesive layer ensures high light transmittance and stability.
It achieves rapid and uniform heating, improves defogging and defrosting efficiency, reduces energy consumption, extends service life, and maintains high light transmittance and aesthetics.
Smart Images
Figure CN224265133U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the automotive field, and more particularly to a heating film for automotive defogging and defrosting. Background Technology
[0002] Car side mirrors are used to reflect the situation behind, to the sides, and below the vehicle, allowing drivers to indirectly see these areas and playing a crucial role in driving safety. However, in cold or damp environments, frost or water vapor easily condenses on the surface of the mirrors, obstructing the view and hindering the driver's ability to accurately judge the situation behind the vehicle, creating a safety hazard. Currently, side mirrors are usually equipped with heating structures for defrosting and defogging. These heating structures typically use resistance wires, which require a large installation space, have low energy efficiency, slow heating speed, and poor defrosting and defogging effects. Utility Model Content
[0003] In view of this, the present invention provides a heating film for automotive defogging and defrosting that has a simple structure and fast heating speed.
[0004] The objective of this utility model is achieved through the following technical solution:
[0005] A heating film for automotive defogging and defrosting includes:
[0006] A transparent substrate having a first surface and a second surface disposed opposite to each other;
[0007] The heating structure includes a transparent electrothermal film laminated on the first surface of the transparent substrate, and two conductive strips electrically connected to the transparent electrothermal film and spaced apart from each other.
[0008] A transparent adhesive layer covers the second surface of the transparent substrate;
[0009] The transparent substrate has two bends at its edges, which are opposite to each other and spaced apart. The transparent electrothermal film extends into the two bends, and the two conductive strips are located within the two bends respectively.
[0010] In the aforementioned technical solution, the combined design of the transparent electrothermal film and the conductive strip allows the transparent electrothermal film to heat up when the conductive strip is energized. This overall heating is achieved through the conductive structure uniformly covering the transparent substrate, resulting in rapid temperature rise and avoiding the localized temperature differences caused by traditional metal wire heating. This improves the efficiency and uniformity of defogging and defrosting. Secondly, the layered structure of the transparent substrate, electrothermal film, and transparent adhesive layer maintains high light transmittance while ensuring heating functionality, preventing the film layers from affecting optical performance or obstructing the driver's view. Furthermore, by placing the conductive strip at the bend in the transparent substrate, mechanical strength is improved, and the bend also encapsulates the conductive strip, preventing it from being exposed to the external environment, reducing the risk of oxidation or physical damage, extending its service life, and enhancing aesthetics while avoiding visual interference for the driver.
[0011] Optionally, in one possible implementation, the transparent substrate is a flexible structure, and the light transmittance of the transparent substrate is 85%-97%.
[0012] In the above technical solution, the flexible substrate has a variable-shape curved surface characteristic, avoiding the film cracking or peeling problems caused by stress concentration in traditional rigid substrates. The high light transmittance range of 85%-97% ensures the heating function while maximizing the light transmittance of the heating film, preventing excessive light obstruction during use.
[0013] Alternatively, in one possible implementation, the edge contour of the transparent substrate matches the rearview mirror or lampshade of a car.
[0014] In the aforementioned technical solution, customized contour design can precisely cover the observation area of the rearview mirror or the curvature of the lamp cover surface, ensuring a seamless fit between the heating film and the target area. This avoids localized heating failure caused by gaps at the edges, thereby improving the defogging and defrosting efficiency in critical areas. Furthermore, by aligning the edge geometry with the contour of the automotive components, non-transparent elements such as conductive strips can be hidden within the gaps in the component structure, avoiding visual obstruction caused by exposed electrodes.
[0015] Alternatively, in one possible implementation, the transparent electrothermal film is formed by magnetron sputtering a layer of electrothermal material onto the first surface of the transparent substrate.
[0016] In the above technical solution, the magnetron sputtering process can achieve uniform deposition of nanoscale thin films by constraining the trajectory of electrons with a magnetic field, accurately control the consistency of the electrothermal film thickness and conductivity, avoid the film thickness fluctuation problem of traditional coating processes, and thus ensure the stability of heating power.
[0017] Optionally, in one possible implementation, the electrothermal material is any one of antimony-doped tin oxide, fluorine-doped tin oxide, cadmium stannate, tin-doped indium oxide, cadmium oxide, aluminum-doped zinc oxide, magnesium-doped zinc oxide, fluorine-doped zinc oxide, sulfur-doped zinc oxide, nickel oxide, cuprous oxide, and tin monoxide.
[0018] All of the aforementioned materials are semiconductor materials, possessing excellent electrothermal conversion rates, with conversion efficiencies far exceeding those of resistance wires. Therefore, they all exhibit superior heating performance, enabling rapid and uniform heating of the transparent heating film, thereby improving its overall heating efficiency and effectively reducing energy consumption, thus saving energy. Furthermore, these semiconductor heating materials do not produce harmful substances during production and use, making them environmentally friendly and more eco-friendly.
[0019] Optionally, in one possible implementation, the thickness of the transparent electrothermal film is 5-100 nm.
[0020] In the above technical solution, the nanoscale film thickness can minimize the absorption and scattering of visible light, and the ultra-thin structure of 5-100nm significantly reduces the heat capacity, allowing the electrothermal film to reach the working temperature within seconds after being powered on, thus shortening the start-up time for defrosting and defogging; its low thermal inertia can also reduce the energy consumption of continuous heating and improve energy utilization efficiency.
[0021] Optionally, in one possible implementation, the transparent electrothermal film completely overlaps with the first surface of the transparent substrate, or the outer edge of the transparent electrothermal film is 0.5-1.0 mm smaller than the outer edge of the transparent electrothermal film.
[0022] In the above technical solution, when the electrothermal film completely covers the substrate surface, the film layer and the substrate form a maximum contact area. The chemical bonding effect generated by the sputtering process enhances adhesion and avoids the risk of edge peeling. The design of reducing the outer edge of the transparent electrothermal film by 0.5-1.0mm, by reserving a buffer area, can effectively release the interfacial stress between the substrate and the transparent electrothermal film during thermal expansion or mechanical deformation, and prevent edge cracking caused by differences in material coefficients.
[0023] Optionally, in one possible implementation, each of the two conductive strips has a pad at one end, and a wire is soldered to each of the two pads, with the wire electrically connected to the corresponding pad.
[0024] In the above technical solution, the independent pad structure provides a precise positioning reference for the wire, avoiding the positional deviation of traditional free soldering, and also facilitating the soldering of the wire, giving the wire an attachment point.
[0025] Alternatively, in one possible implementation, the transparent adhesive layer is a heat-resistant double-sided adhesive layer.
[0026] In the above technical solution, the heat-resistant double-sided adhesive layer can maintain its adhesive strength under high-temperature conditions, avoiding delamination failure caused by thermal expansion or thermal stress. At the same time, it can firmly bond heterogeneous materials such as glass, metal, and plastic, reducing the risk of delamination. Attached Figure Description
[0027] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0028] Figure 1 This is a cross-sectional view of a heating film according to one embodiment.
[0029] Figure 2 This is a front view of a heating film according to an embodiment.
[0030] Reference numerals: 1-Transparent substrate; 11-Bending part; 2-Heating structure; 21-Transparent electrothermal film; 22-Conductive strip; 221-Solder pad; 3-Transparent adhesive layer; 4-Wire. Detailed Implementation
[0031] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0032] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0033] Please refer to Figure 1 and Figure 2This embodiment provides a heating film for automotive defogging and defrosting, comprising: a transparent substrate 1, a heating structure 2, and a transparent adhesive layer 3; the transparent substrate 1 has a first surface and a second surface disposed opposite to each other; the heating structure 2 includes a transparent electrothermal film 21 laminated on the first surface of the transparent substrate 1, and two conductive strips 22 electrically connected to and spaced apart from the transparent electrothermal film 21; the transparent adhesive layer 3 covers the second surface of the transparent substrate 1; wherein, the edges of the transparent substrate 1 are respectively provided with two bending portions 11, the two bending portions 11 being opposite to each other and spaced apart, the transparent electrothermal film 21 extending into the two bending portions 11, and the two conductive strips 22 being located within the two bending portions 11 respectively. Specifically, the two bending portions 11 are integrally formed with the transparent substrate 1, and can be bent relative to the transparent substrate 1. When the heating film is attached to the rearview mirror of the car, the bending portions 11 can be bent relative to each other to hide behind the rearview mirror, thereby hiding the conductive strips 22 and improving aesthetics.
[0034] This embodiment utilizes a design combining a transparent electrothermal film 21 and a conductive strip 22. When the conductive strip 22 is energized, the transparent electrothermal film 21 heats up, achieving overall heating through a conductive structure uniformly covering the transparent substrate 1. This rapid temperature rise avoids the localized temperature differences caused by traditional metal wire heating, thus improving the efficiency and uniformity of defogging and defrosting. Secondly, the layered structure of the transparent substrate 1, the electrothermal film, and the transparent adhesive layer maintains high light transmittance while ensuring heating functionality, preventing the film layers from affecting optical performance or obstructing the driver's view. Furthermore, by placing the conductive strip 22 within the bend 11 of the transparent substrate 1, mechanical strength is improved, and the bend 11 encapsulates the conductive strip 22, preventing it from being exposed to the external environment, reducing the risk of oxidation or physical damage, extending its service life, and enhancing aesthetics while avoiding visual interference for the driver.
[0035] In this embodiment, the transparent substrate 1 is a flexible structure, and its light transmittance is 85%-97%. For example, the transparent substrate 1 in this embodiment is made of PET material, i.e., polyethylene terephthalate. The overall transparency of the heating film is maintained above 80%, thus meeting the light transmittance requirements.
[0036] The flexible substrate has a variable shape and curved surface, which can avoid the film cracking or peeling problems caused by stress concentration in traditional rigid substrates. The high light transmittance range of 85%-97% ensures that the heating function is guaranteed while maintaining the light transmittance of the heating film to the maximum extent, so that it does not block light excessively during use.
[0037] It should be noted that the edge contour of the transparent substrate 1 matches the rearview mirror or lamp cover of the car. In other words, the heating film can be applied to the surface of the rearview mirror or lamp cover to heat it. When the heating film is applied to the rearview mirror, it can defrost and defog it, preventing frost and fog from obstructing the driver's vision. When the heating film is applied to the lamp cover, it can defrost and defog it, preventing frost and fog from affecting the light's penetration and ensuring good illumination.
[0038] Through customized contour design, the curvature of the rearview mirror observation area or lamp cover surface can be precisely covered, ensuring a seamless fit between the heating film and the target area. This avoids localized heating failure caused by gaps at the edges, thereby improving the defogging and defrosting efficiency in critical areas. Furthermore, by aligning the edge geometry with the contour of the automotive components, non-transparent elements such as the conductive strip 22 can be hidden within the gaps in the component structure, avoiding visual obstruction caused by exposed electrodes.
[0039] In this embodiment, the transparent electrothermal film 21 is formed by magnetron sputtering an electrothermal material onto the first surface of the transparent substrate 1. The magnetron sputtering process uses a magnetic field to constrain the trajectory of electrons, enabling uniform deposition of nanoscale thin films, precise control of the consistency of the electrothermal film thickness and conductivity, and avoiding the film thickness fluctuation problem of traditional coating processes, thereby ensuring the stability of heating power.
[0040] Specifically, the heating material is any one of antimony-doped tin oxide, fluorine-doped tin oxide, cadmium stannate, tin-doped indium oxide, cadmium oxide, aluminum-doped zinc oxide, magnesium-doped zinc oxide, fluorine-doped zinc oxide, sulfur-doped zinc oxide, nickel oxide, cuprous oxide, and tin monoxide.
[0041] All of the aforementioned materials are semiconductor materials, possessing excellent electrothermal conversion rates, with conversion efficiencies far exceeding those of resistance wires. Therefore, they all exhibit superior heating performance, enabling rapid and uniform heating of the transparent heating film 21, thereby improving its overall heating efficiency and effectively reducing energy consumption and saving energy. Furthermore, these semiconductor heating materials do not produce harmful substances during production and use, making them environmentally friendly and more eco-friendly.
[0042] The thickness of the transparent electrothermal film 21 in this embodiment is 5-100 nm. The nanoscale film thickness can minimize the absorption and scattering of visible light, and the ultra-thin structure of 5-100 nm significantly reduces the heat capacity, allowing the electrothermal film to reach the working temperature within seconds after being energized, thus shortening the start-up time for defrosting and defogging; its low thermal inertia can also reduce the energy consumption of continuous heating and improve energy utilization efficiency.
[0043] As different implementations, the transparent electrothermal film 21 may completely overlap with the first surface of the transparent substrate 1, or the outer edge of the transparent electrothermal film 21 may be 0.5-1.0 mm smaller than the outer edge of the transparent electrothermal film 21.
[0044] When the electrothermal film completely covers the substrate surface, the film layer and the substrate form a maximized contact area. The chemical bonding generated by the sputtering process enhances adhesion and avoids the risk of edge peeling. The design of reducing the outer edge of the transparent electrothermal film 21 by 0.5-1.0mm, by reserving a buffer area, effectively releases the interfacial stress between the substrate and the transparent electrothermal film 21 during thermal expansion or mechanical deformation, preventing edge cracking due to differences in material coefficients. Therefore, it can be flexibly selected according to different application scenarios.
[0045] In this embodiment, each of the two conductive strips 22 has a pad 221 at one end, and a wire 4 is soldered to each of the two pads 221. The wire 4 is electrically connected to the corresponding pad 221. The independent pad 221 structure provides a precise positioning reference for the wire 4, avoiding the positional deviation of traditional free soldering, and also facilitating the soldering of the wire, giving the wire an attachment point. In addition, the conductive strips 22 in this embodiment are silver paste metal wires.
[0046] In this embodiment, the transparent adhesive layer 3 is a heat-resistant double-sided adhesive layer. The heat-resistant double-sided adhesive layer can maintain its adhesive strength under high-temperature conditions, avoiding delamination failure caused by thermal expansion or thermal stress. It can also firmly bond dissimilar materials such as glass, metal, and plastic, reducing the risk of delamination. Specifically, the heat-resistant double-sided adhesive layer can be made of polyimide, silicone pressure-sensitive adhesive, or acrylate-modified adhesive, etc.
[0047] In the description of this utility model, it should be understood that terms such as "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.
[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0049] 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 heating film for automotive defogging and defrosting, characterized in that, include: A transparent substrate having a first surface and a second surface disposed opposite to each other; The heating structure includes a transparent electrothermal film laminated on the first surface of the transparent substrate, and two conductive strips electrically connected to the transparent electrothermal film and spaced apart from each other. A transparent adhesive layer covers the second surface of the transparent substrate; The transparent substrate has two bends at its edges, which are opposite to each other and spaced apart. The transparent electrothermal film extends into the two bends, and the two conductive strips are located within the two bends respectively.
2. The heating film for automotive defogging and defrosting according to claim 1, characterized in that, The transparent substrate has a flexible structure and a light transmittance of 85%-97%.
3. The heating film for automotive defogging and defrosting according to claim 1, characterized in that, The edge contour of the transparent substrate matches the rearview mirror or lampshade of a car.
4. The heating film for automotive defogging and defrosting according to claim 1, characterized in that, The transparent electrothermal film is formed by magnetron sputtering a layer of electrothermal material onto the first surface of the transparent substrate.
5. The heating film for automotive defogging and defrosting according to claim 4, characterized in that, The electrothermal material is any one of antimony-doped tin oxide, fluorine-doped tin oxide, cadmium stannate, tin-doped indium oxide, cadmium oxide, aluminum-doped zinc oxide, magnesium-doped zinc oxide, fluorine-doped zinc oxide, sulfur-doped zinc oxide, nickel oxide, cuprous oxide, and tin monoxide.
6. The heating film for automotive defogging and defrosting according to claim 1, characterized in that, The thickness of the transparent electrothermal film is 5-100 nm.
7. The heating film for automotive defogging and defrosting according to claim 1, characterized in that, The transparent electrothermal film is completely overlapped with the first surface of the transparent substrate, or the outer edge of the transparent electrothermal film is 0.5-1.0 mm smaller than the outer edge of the transparent electrothermal film.
8. The heating film for automotive defogging and defrosting according to claim 1, characterized in that, Each of the two conductive strips has a pad at one end, and a wire is welded to each of the two pads. The wire is electrically connected to the corresponding pad.
9. The heating film for automotive defogging and defrosting according to claim 1, characterized in that, The transparent adhesive layer is a heat-resistant double-sided adhesive layer.