Flexible heating assembly

Abstract

The invention provides a flexible heating assembly, and belongs to the field of heating material manufacturing. The packaging film comprises a conductive film, two layers of anti-tearing films, two layers of packaging films and two layers of packaging cloth, the two sides of the conductive film are connected with the packaging films through the anti-tearing films respectively. The outer sides of the two layers of packaging films are both covered with a layer of packaging cloth, and each layer of packaging cloth is located on the side away from the conductive film. The anti-tearing film is a PET (polyethylene terephthalate) film or a PI (polyimide) film. The flexible heating assembly is low in thickness, good in flexibility, waterproof, resistant to scrubbing and long in service life.

Description

Technical Field

[0001] The invention relates to medical device manufacturing technology, in particular to a flexible heating component, and belongs to the technical field of medical product manufacturing. Background Art

[0002] Flexible heating film is a kind of flexible heating material. This kind of material is made by encapsulating flexible heating sheets with different insulating materials. According to the different materials of insulating materials, it can generally be divided into polyimide (PI) heating film, polyester (PET) heating film, silicone rubber heating film and other types. According to the different materials of heating sheets, it can be divided into metal wire heating film, etched metal sheet heating film, resistance slurry heating film, carbon film (generally refers to carbon crystal, graphene, carbon nanotube) heating film and other types. Flexible heating film has the advantages of being light, soft, easy to install, and fast heating speed. It has been widely used in many fields such as equipment, pipelines, medical equipment, automobiles, power batteries, smart wearables, etc.

[0003] As the requirements for the softness and comfort of wearable products increase, the requirements for heating management are also getting higher and higher. Flexible heating films need to improve safety while improving wearing comfort. Especially when underwear, socks, gloves and other close-fitting clothing are in direct contact with the skin, the management of heating is more stringent. In particular, the heating of clothing in outdoor sports, extremely cold environments, border military defense and other applications requires not only good heating uniformity of the heating component, but also sufficient lightness and thinness. Summary of the invention

[0004] The present invention provides a new flexible heating component, which can form a heating material with good softness and high stability by reasonably arranging on both sides of a conductive film, so as to solve the technical problems in the prior art that the heating film has poor stability and is not light and thin enough.

[0005] The flexible heating assembly of the embodiment of the present invention comprises: a conductive film, two layers of tear-resistant films, two layers of packaging films and two layers of packaging cloth; the two sides of the conductive film are respectively connected to a layer of the packaging film through a layer of the tear-resistant film; the outer sides of the two layers of the packaging film are covered with a layer of the packaging cloth, and each layer of the packaging cloth is located on a side away from the conductive film;

[0006] The anti-tearing film is a PET film or a PI film.

[0007] In the flexible heating assembly as described above, both sides of the anti-tear film are coated with adhesive layers; the anti-tear film is connected to the conductive film and the packaging film through the adhesive layers.

[0008] In the flexible heating assembly as described above, the thickness of the conductive film is 30-40 μm; the thickness of the anti-tear film is 20-30 μm; and the thickness of the adhesive layer is 10-25 μm.

[0009] The flexible heating component as described above, wherein a copper foil layer is provided between the packaging film and the anti-tear film; a receiving groove is provided on the anti-tear film connected to the copper foil layer, and the receiving groove is filled with conductive glue; the copper foil layer is connected to the conductive film through the conductive glue.

[0010] In the flexible heating assembly as described above, one side of the copper foil layer is connected to the conductive film through the tear-resistant film and the conductive adhesive; an additional layer of PI film is arranged between the other side of the copper foil layer and the packaging film.

[0011] In the flexible heating assembly as described above, a copper foil strip is arranged between the packaging film and the anti-tear film; a conductive adhesive strip is arranged on the copper foil strip and is connected to the conductive film through the conductive adhesive strip.

[0012] The flexible heating assembly as described above, wherein the copper foil strip has a thickness of 15-20 μm.

[0013] The flexible heating component as described above, wherein the adhesive layer is TPU thermoplastic hot melt adhesive or EVA thermoplastic hot melt adhesive.

[0014] In the flexible heating assembly as described above, the conductive film is made of a graphene coating coated on a fiber cloth or a flame-retardant cloth, and the coating thickness on both sides of the fiber cloth or the flame-retardant cloth is different.

[0015] The flexible heating component as described above, wherein the packaging film is a TPU film or an EVA hot melt adhesive film; the packaging cloth is any one of a fiber cloth, a polyester cloth, a nylon cloth, and a fiber cloth.

[0016] In the embodiment of the present invention, the conductive film is covered with tear-resistant films on both sides to ensure the stability and damage resistance of the conductive film; thereby ensuring that the conductive film is completely waterproof and has excellent stability and flexibility, and can be directly washed with water. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a side structural diagram of a flexible heating assembly according to an embodiment of the present invention;

[0018] Figure 2 is a side structural diagram of a flexible heating assembly according to another embodiment of the present invention;

[0019] Figure 3 This is a side structural diagram of a flexible heating assembly according to another embodiment of the present invention. DETAILED DESCRIPTION

[0020] The flexible heating component described in the present invention can be made of the following materials and components, but is not limited to the following materials and components, for example: PI, TPU, EVA, conductive film, graphene, fiber cloth, etc.

[0021] like Figure 1 The figure shows a side structural diagram of a flexible heating assembly according to an embodiment of the present invention; the flexible heating assembly according to the present embodiment comprises: a conductive film 1, two layers of tear-resistant films 2, two layers of packaging films 3 and two layers of packaging cloth 30; both sides of the conductive film 1 are connected to a layer of the packaging film 3 through a layer of the tear-resistant film 2; the outer sides of the two layers of the packaging film 3 are covered with a layer of the packaging cloth 30, and each layer of the packaging cloth 30 is located on a side away from the conductive film 1;

[0022] The anti-tearing film is a PET film or a PI film.

[0023] Generally, both sides of the anti-tear film 2 are coated with an adhesive layer 20 ; the anti-tear film 2 is connected to the conductive film 1 and the packaging film 3 via the adhesive layer 20 .

[0024] In this embodiment, the conductive film 1 is made of a fiber cloth or a flame retardant cloth coated with a graphene coating, and the coating thickness on both sides of the fiber cloth or the flame retardant cloth is different. The different coating thicknesses can achieve different resistivities on both sides, so that the heating effect is concentrated on one side, which is more conducive to the heating of the product.

[0025] Typically, the packaging film 3 is a TPU film or an EVA hot melt adhesive film; the packaging cloth 30 is any one of fiber cloth, polyester cloth, nylon cloth, and fiber cloth.

[0026] EVA hot melt adhesive film, also known as environmentally friendly film, is a film produced by cast extrusion of EVA raw materials. It is a new generation of green, environmentally friendly and degradable material. It is biodegradable and will not cause harm to the environment when discarded or burned. It has a light specific gravity of about 0.93, is odorless, does not contain heavy metals, does not contain phthalates, is highly transparent, soft and tough, and has super low temperature resistance (-70 degrees), resistance to water, salt and other substances, and high heat resistance.

[0027] PI film, also known as polyimide film (Polyimide Film), is the best performing thin-film insulating material in the world. It is made by polycondensing pyromellitic dianhydride (PMDA) and diaminodiphenyl ether (ODA) in a strong polar solvent and casting into a film, followed by imidization.

[0028] PET film, also known as polyester substrate, is a durable, strong, high-toughness material that is resistant to moisture, high temperatures and low temperatures.

[0029] TPU (Thermoplastic polyurethanes), thermoplastic TPU elastomer, is made by extrusion and mixing MDI containing NCO functional groups and POLYOL and 1.4BG containing OH functional groups. Due to its good elasticity, good physical properties and good mechanical strength, it is widely used in processing methods such as injection, extrusion, calendering and dissolving into solution-type resin. It is a plastic material frequently used by plastic processing industries.

[0030] Generally, the thickness of the conductive film is 30-40μm, preferably 35μm; the thickness of the anti-tear film is 20-30μm, preferably 25μm; the adhesive layer is TPU thermoplastic hot melt adhesive or EVA thermoplastic hot melt adhesive. The thickness of the adhesive layer is 10-25μm, preferably 15μm. The thickness of the anti-tear film can be from 20μm to 30μm. Exceeding this range, the film will have a plastic sound and feel, is not soft, and is not suitable for clothing; the thickness of the adhesive layer 20 can be from 10-20μm. Too thin will result in the glue not adhering, and the anti-tear film will be separated from the release film required for assembly. Too thick will result in insufficient softness and comfort after the assembly is completed.

[0031] In the embodiment of the present invention, the anti-tear film (taking PI film as an example) is adhered to the conductive film by the double-sided tape coated thereon, so as to provide a carrier for the conductive cloth, thereby ensuring that the conductive film and the slurry thereon will not produce a large amount of displacement. At the same time, the anti-tear films on both sides are adhered to each other by the double-sided tape to form a structure similar to an edge wrapping, which completely wraps the conductive film to achieve waterproofing and enhance its stability. The present invention ensures the stability and damage resistance of the conductive film by covering the anti-tear film on both sides of the conductive film. Thus, it is ensured that the conductive film is completely waterproof and has excellent stability and flexibility, and can be directly washed with water.

[0032] like Figure 2 As shown; in another embodiment of the flexible heating assembly of the present invention, a copper foil layer 5 is provided between the packaging film 3 and the anti-tear film 2; a receiving groove is provided on the anti-tear film 2 connected to the copper foil layer 5, and the receiving groove is filled with a conductive adhesive 50; the copper foil layer 5 is connected to the conductive film 1 through the conductive adhesive 50. Generally, the thickness of the copper foil layer is 18 μm.

[0033] Furthermore, one side of the copper foil layer 5 is connected to the conductive film 1 through the tear-resistant film 2 and the conductive adhesive 50; an additional layer of PI film 6 is provided between the other side of the copper foil layer 5 and the packaging film 3. Adhesive layers 60 are provided on both sides of the PI film 6 to facilitate the connection of the connected film structures.

[0034] At the same time, the width of the PI film 6 is greater than the copper foil layer 5, so that the copper foil layer is completely wrapped to prevent water from entering the copper foil layer 5. As a reinforcing adhesive, the PI film 6 is only used to wrap the copper foil layer 5 in the FPC (flexible circuit board) area. It is rectangular in shape and can directly cover the FPC in one piece. After hot pressing with the component, it can ensure the normal use of the FPC and achieve a better hot pressing bonding effect. At the same time, the package at the FPC outlet can be reinforced to ensure that the entire component can completely avoid peeling in the subsequent water washing test.

[0035] In actual use, the height of the conductive adhesive 50 is slightly higher than the top of the anti-tearing film 2 so as to fully contact the copper foil layer 50 and eliminate assembly problems caused by poor contact.

[0036] The area of ​​the window of the anti-tear film 2, that is, the area where the conductive glue 50 is filled and applied, is smaller than the exposed copper area of ​​the copper foil layer. This structure allows the copper foil layer 5 to completely wrap the conductive glue 50 in the subsequent hot pressing process to avoid problems such as short circuits that may be caused by overflow of the conductive glue. It is also convenient for assembly without worrying about assembly problems caused by deviations.

[0037] like Figure 3 As shown; in a flexible heating component of another embodiment of the present invention, a copper foil strip 7 is arranged between the packaging film 3 and the anti-tear film 2; a conductive adhesive strip 70 is arranged on the copper foil strip 7 and is connected to the conductive film 1 through the conductive adhesive strip 70.

[0038] Generally, the thickness of the copper foil strip 7 is 15-20 μm, preferably 18 μm.

[0039] The bending test data of the present invention are as follows.

[0040] Bending test: The same point was bent 360° and the manual bending test was performed 500 times. The local heating temperature was 50.1°C before bending, 50.3°C after bending 50 times, 51.3°C after bending 100 times, 53.3°C after bending 200 times, 51.3°C after bending 300 times, 50.2°C after bending 400 times, and 51.2°C after bending 500 times. After 500 bends, the overall component did not produce obvious local hot spots, and the overall heating effect was uniform and the heating temperature was normal.

[0041] In the bending test, the initial state of the bending point is 51.3℃ for normal operation, 50.9℃ for normal operation after 50 bends, 52.2℃ for normal operation after 100 bends, 53.0℃ for normal operation after 200 bends, 50.9℃ for normal operation after 300 bends, and 51.3℃ for normal operation after 400 bends. There is no obvious temperature increase after several bends, and the bending resistance is good.

[0042] In addition, the flexible heating component of the present invention has low production cost, exquisite layout, compact structural design, stable finished product quality, good flexibility, waterproof, washable, long life, uniform heat generation, and is suitable for various clothing, floor mats, seat cushions, physical therapy devices and other heating products that are in direct contact with the human body.

[0043] The serial numbers of the above embodiments of the present invention are for description only and do not represent the advantages and disadvantages of the embodiments. Through the description of the above implementation methods, those skilled in the art can clearly understand that the above embodiment methods can be implemented by means of some deformations plus the necessary general technology superposition; of course, they can also be implemented by simplifying some important technical features. Based on this understanding, the technical solution of the present invention is essentially or contributes to the prior art in the following aspects: the overall structure and connection method, and the structure described in each embodiment of the present invention.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements 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 heating assembly, characterized in that: include: Conductive film, two layers of tear-resistant film, two layers of packaging film and two layers of packaging cloth; both sides of the conductive film are connected to a layer of the packaging film through a layer of the tear-resistant film; the outer sides of the two layers of the packaging film are covered with a layer of the packaging cloth, and each layer of the packaging cloth is located on a side away from the conductive film; The tear-resistant film is a PET film or a PI film.

2. The flexible heating assembly according to claim 1, characterized in that: Both sides of the anti-tear film are coated with adhesive layers; the anti-tear film is connected to the conductive film and the packaging film through the adhesive layers.

3. The flexible heating assembly according to claim 1, characterized in that: The thickness of the conductive film is 30-40 μm; the thickness of the anti-tearing film is 20-30 μm; and the thickness of the adhesive layer is 10-25 μm.

4. The flexible heating assembly according to any one of claims 1 to 3, characterized in that: A copper foil layer is arranged between the packaging film and the anti-tear film; a receiving groove is opened on the anti-tear film connected to the copper foil layer, and the receiving groove is filled with conductive glue; the copper foil layer is connected to the conductive film through the conductive glue.

5. The flexible heating assembly according to claim 4, characterized in that: One side of the copper foil layer is connected to the conductive film through the tear-resistant film and the conductive adhesive; an additional layer of PI film is arranged between the other side of the copper foil layer and the packaging film.

6. The flexible heating assembly according to any one of claims 1 to 3, characterized in that: A copper foil strip is arranged between the packaging film and the anti-tearing film; a conductive adhesive strip is arranged on the copper foil strip, and is connected to the conductive film through the conductive adhesive strip.

7. The flexible heating assembly according to claim 6, characterized in that: The copper foil strip has a thickness of 15-20 μm.

8. The flexible heating assembly according to any one of claims 2-3, characterized in that: The adhesive layer is TPU thermoplastic hot melt adhesive or EVA thermoplastic hot melt adhesive.

9. The flexible heating assembly according to any one of claims 1 to 3, characterized in that: The conductive film is made of a fiber cloth or a flame retardant cloth coated with a graphene coating, and the coating thicknesses on both sides of the fiber cloth or the flame retardant cloth are different.

10. The flexible heating assembly according to any one of claims 1 to 3, characterized in that: The packaging film is a TPU film or an EVA hot melt adhesive film; the packaging cloth is any one of fiber cloth, polyester cloth, nylon cloth, and fiber cloth.

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