Electric heating fabric, preparation method therefor and use thereof

Abstract

Provided in the present application are an electric heating fabric, a preparation method therefor and the use thereof. The electric heating fabric comprises a fiber cloth; an electric heating film is provided on one or both side surfaces of the fiber cloth; the electric heating film has a wave-transmitting function and is formed by curing a conductive paste; the conductive paste comprises a resin, a dispersant, a carbon material, a functional compound and a solvent; and the functional compound comprises a nitrogen-containing compound and / or an acidic compound. By adding the specific functional compound to raw materials for preparing the electric heating film, the present application uses a cross-linking reaction between the functional compound and a resin in a composite material to effectively improve the interface bonding performance between the electric heating film and the composite material, thus further ensuring the long-term stability and reliability of the obtained electric heating fabric and integrated composite materials thereof in extreme use environments; and the electric heating fabric has a wave-transmitting function, and is suitable for application on surfaces of aircrafts.

Description

An electrically heated fabric, its preparation method and application Technical Field

[0001] This application belongs to the field of electric heating element technology, specifically relating to an electric heating fabric, its preparation method, and its application. Background Technology

[0002] When an aircraft encounters icing weather conditions, supercooled water droplets in the atmosphere impact the aircraft's surface, particularly critical components such as fixed wings, rotors, tail rotors, air intakes, windshields, radomes, and instrument sensors, easily forming ice. This phenomenon not only significantly increases the aircraft's weight burden but also severely disrupts its aerodynamic shape, thereby affecting its aerodynamic characteristics and posing a major threat to flight safety. To address this challenge, electrothermal de-icing technology, with its advantages of high efficiency, flexibility, and ease of maintenance, has become one of the most widely researched and applied de-icing methods.

[0003] Traditional metal or carbon fiber heating elements often suffer from uneven heating due to their linear layout. In contrast, emerging heating modules such as carbon nanotube paper, carbon fiber cloth, and graphene films exhibit superior planar heating uniformity. For example, CN110816854A discloses a composite woven electric heating film and electric heating structure for de-icing. The electric heating film obtained by this invention is flexible and can be laid on the surface of complex-shaped parts. It not only has excellent electrical and thermal conductivity, but also improves mechanical properties and electrothermal conversion efficiency. More importantly, the composite woven electric heating film is lighter than metal mesh. The composite woven electric heating film and insulating film can be wrapped, adhered, or wound onto the surface of the object being heated, and it can be used, especially, for de-icing of composite material parts in aircraft. For example, CN116506982A discloses a high-strength flexible electrothermal film anti-icing element based on graphene, comprising a laminated plate structure. The laminated plate structure includes a heating layer and an adhesive layer. The heating layer comprises two layers of graphene and carbon fiber filaments encased within the two graphene layers. The adhesive layer comprises a tensile layer and a base layer. The base layer and the tensile layer are modified to form an integrated structure. The carbon fiber filaments have an arc-shaped structure. This invention combines carbon fiber tubes and carbon fiber filaments to prepare a flexible electrothermal film. The heating layer is an arc-shaped fabric with unit-arranged carbon fiber bundles and two layers of graphene. Experiments have shown that this method achieves good toughness.

[0004] Nevertheless, the electric heating elements provided in the related technologies, including the inventions mentioned above, when applied to the surfaces of equipment such as radar and antennas that require electromagnetic wave transmission, still interfere with the transmission of electromagnetic waves due to their high conductivity and high reflectivity, thereby affecting the normal operation of the equipment. In addition, most electric heating elements currently rely mainly on adhesives when bonding to aircraft parts, but this method often ignores the problem of poor interfacial adhesion between the two.

[0005] Therefore, in view of the above-mentioned technical problems, this application provides an electrically heated fabric that has both electric heating and wave transmission functions, and has excellent interfacial properties when integrated with composite materials. Summary of the Invention

[0006] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims.

[0007] This application provides an electrically heated fabric, its preparation method, and its application. The electrically heated fabric, while possessing both electrical heating and wave transmission functions, also exhibits excellent interfacial properties when integrated with composite materials, thereby ensuring long-term stability and reliability in extreme environments and making it suitable for application on aircraft surfaces.

[0008] In a first aspect, this application provides an electrically heated fabric, the electrically heated fabric comprising a fiber cloth, wherein an electrically heated film is disposed on one or both sides of the fiber cloth, and the electrically heated film has a wave-transmitting function;

[0009] The electric heating film is formed by curing a conductive slurry, which includes resin, dispersant, carbon material, functional compound and solvent, and the functional compound includes nitrogen-containing compound and / or acidic compound;

[0010] Sheet resistance, also known as sheet resistance, is the resistance between edges of a square thin-film conductive material. It is measured using a four-probe method on a square sample and can also be directly written as "surface resistance." The unit is Ω, and the numerical value remains the same. The sheet resistance of the electrically heated fabric ranges from 10 to 3000 Ω / □, for example, 10 Ω / □, 20 Ω / □, 50 Ω / □, 100 Ω / □, 150 Ω / □, 500 Ω / □, 1000 Ω / □, 1500 Ω / □, 2000 Ω / □, 2500 Ω / □, or 3000 Ω / □, etc.

[0011] The electrically heated fabric provided in this application includes a fiber cloth, on one or both sides of which an electrically heated film is disposed. The electrically heated film is defined to have a wave-transmitting function and is formed by curing a conductive slurry. The conductive slurry includes resin, dispersant, carbon material, functional compound, and solvent, and the functional compound is further defined to include nitrogen-containing compound and / or acidic compound. The added specific functional compound can undergo an efficient cross-linking reaction with the epoxy resin during the molding of the composite material. This cross-linking reaction can greatly improve the interfacial bonding between materials, thereby enabling the electrically heated film to have excellent interfacial adhesion performance with the substrate (composite material). The two can be firmly and permanently bonded together, thus ensuring the long-term stability and reliability of the obtained electrically heated fabric and its integrated composite material under extreme operating environments. It also has a wave-transmitting function and is suitable for application on aircraft surfaces.

[0012] It should be noted that if the electrically heated fabric provided in this application has an electrically heated film on only one side of the fiber cloth, then the side of the electrically heated film should be close to the substrate (composite material) during use.

[0013] In some preferred embodiments, the fiber cloth includes nonwoven fiber cloth or woven fiber cloth; and this application does not have any special requirements on the weave form of the woven fiber cloth.

[0014] Specifically, the fiber cloth can be a unidirectional fiber cloth, plain weave cloth, twill weave cloth, or satin weave cloth.

[0015] In some preferred embodiments, the fiber cloth contains inorganic fibers and / or organic fibers, and this application does not have any special requirements on the specific types of inorganic and organic fibers.

[0016] Specifically, the inorganic fibers include any one or a combination of at least two of glass fibers, ceramic fibers, alumina fibers, or quartz fibers.

[0017] Specifically, the organic fiber includes any one or a combination of at least two of polyester fiber, polyimide fiber, poly(p-benzimidazole) fiber, or aramid fiber.

[0018] In some preferred embodiments, the thickness of the electric heating film is 0.1 to 20 μm, for example, 0.1 μm, 0.5 μm, 1 μm, 2 μm, 4 μm, 6 μm, 8 μm, 10 μm, 12 μm, 14 μm, 16 μm, 18 μm or 20 μm.

[0019] In some preferred embodiments, the conductive paste comprises the following components by weight:

[0020] The amount of resin used can be 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight, or 40 parts by weight, etc.

[0021] The amount of the dispersant can be 0.5 parts by weight, 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight, 5 parts by weight, 6 parts by weight, 8 parts by weight, or 10 parts by weight, etc.

[0022] The amount of carbon material used can be 2 parts by weight, 5 parts by weight, 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight, 40 parts by weight, or 45 parts by weight, etc.

[0023] The amount of the functional compound can be 0.1 parts by weight, 0.5 parts by weight, 1 part by weight, 1.5 parts by weight, 2 parts by weight, 2.5 parts by weight, 3 parts by weight, 3.5 parts by weight, 4 parts by weight, 4.5 parts by weight, or 5 parts by weight, etc.

[0024] The amount of solvent used can be 0 parts by weight, 100 parts by weight, 200 parts by weight, 400 parts by weight, 600 parts by weight, 800 parts by weight, or 1000 parts by weight, etc.

[0025] In some preferred embodiments, the resin includes thermosetting resins and / or thermoplastic resins.

[0026] In some preferred embodiments, the resin includes any one or a combination of at least two of acrylic resin, polyester resin, phenolic resin, epoxy resin, alkyd resin, polyurethane resin, silicone resin, polycarbonate resin, rubber, or polyimide.

[0027] This application does not have any special requirements regarding the type of dispersant in the conductive paste.

[0028] Specifically, the dispersant includes any one or a combination of at least two of the following: active derivatives of polyester backbone structure, urethane copolymers, polyacrylic acid, polymaleic acid and its derivatives, polyethers derived from polyhydroxystearic acid, polycarboxylic acids and their oligomers composed of polyamines.

[0029] In some preferred embodiments, the carbon material includes any one or a combination of at least two of carbon nanotubes, carbon black, graphene, graphene oxide, or graphite.

[0030] In some preferred embodiments, the carbon nanotubes include single-walled carbon nanotubes and / or double-walled carbon nanotubes.

[0031] In some preferred embodiments, the median length of the carbon nanotubes is 0.1 to 1000 μm, such as 0.1 μm, 0.5 μm, 1 μm, 5 μm, 10 μm, 50 μm, 100 μm, 200 μm, 400 μm, 600 μm, 800 μm or 1000 μm, more preferably 1 to 800 μm, and even more preferably 10 to 500 μm.

[0032] In some preferred embodiments, the graphene comprises monolayer graphene and / or multilayer graphene.

[0033] In some preferred embodiments, the average sheet diameter of the graphene and graphene oxide is independently 0.1 to 2000 μm, for example 0.1 μm, 0.5 μm, 1 μm, 5 μm, 10 μm, 50 μm, 100 μm, 500 μm, 1000 μm, 1500 μm or 2000 μm, more preferably 1 to 1000 μm, and even more preferably 5 to 200 μm.

[0034] In some preferred embodiments, the functional compound includes any one or a combination of at least two of aliphatic amines, aromatic amines, organic acid anhydrides, or amine adducts.

[0035] In this application, there are no special requirements for the specific type of aliphatic amines. However, in order to improve the conductivity of the resulting electrically heated fabric and to enhance the long-term stability and reliability of the integrated composite material, the following further preferred limitations are made on the aliphatic amines, aromatic amines, organic acid anhydrides, and amine adducts:

[0036] In some preferred embodiments, the aliphatic amine includes any one or a combination of at least two of the following: diethylenetriamine and its denatured derivatives, triethylenetetramine and its denatured derivatives, unsaturated aliphatic diamines, diethylaminopropylamine, aliphatic amide polyamines, or aliphatic amines containing aromatic rings (referring to amines with an aliphatic main chain and aromatic rings on the side chains).

[0037] In some preferred embodiments, the aromatic amine includes any one or a combination of at least two of the following: m-phenylenediamine, aryl ether diamine, polyaryl ether diamine, diaminodiphenyl sulfone, diaminodiphenylmethane, N-aminoethylpiperazine, 1,3-bis(aminomethyl)cyclohexane, maleimide, or diazanaphthone.

[0038] In some preferred embodiments, the organic acid anhydride includes any one or a combination of at least two of phthalic anhydride and its adducts, pyromellitic dianhydride and its adducts, dimaleic anhydride and its adducts, olefinic succinic anhydride, or methylhexahydrophthalic anhydride.

[0039] In some preferred embodiments, the amine adduct includes any one or a combination of at least two of the following: amine adducts with epoxy compounds, amine adducts with acrylonitrile, and amine adducts with formaldehyde and phenol.

[0040] In this application, there are no special requirements regarding the type of solvent used in the conductive paste.

[0041] Specifically, the solvent includes any one or a combination of at least two of water, acetone, dimethylethanolamine, or ethyl acetate.

[0042] Secondly, this application provides a method for preparing an electrically heated fabric as described in the first aspect, the method comprising the following steps:

[0043] (1) The resin, dispersant, carbon material, functional compound and solvent are mixed to obtain a conductive paste;

[0044] (2) The conductive paste obtained in step (1) is coated on one or both sides of the fiber cloth, and then dried and cured to obtain the electrically heated fabric.

[0045] In some preferred embodiments, the mixing method in step (1) includes any one or a combination of at least two of mechanical stirring, ultrasonication, high-pressure homogenization, or three-roll milling.

[0046] In some preferred embodiments, the coating method in step (2) includes any one or a combination of at least two of the following: blade coating, spray coating, casting, dip coating, or roller coating.

[0047] In this application, there are no special requirements for the curing temperature and time described in step (2), which can be reasonably set according to the type of resin.

[0048] In some preferred embodiments, the curing temperature in step (2) is 50 to 180°C, for example, 50°C, 70°C, 90°C, 100°C, 120°C, 140°C, 160°C or 180°C.

[0049] In some preferred embodiments, the curing time in step (2) is 3 to 30 minutes, for example, 3 minutes, 6 minutes, 9 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes or 30 minutes.

[0050] Thirdly, this application provides an electric heating element comprising an electric heating fabric and a metal electrode as described in the first aspect.

[0051] Fourthly, this application provides an application of the electric heating element as described in the third aspect, including its application on the surface of an aircraft.

[0052] Preferably, the application includes radar or antenna surfaces for aircraft.

[0053] Compared with related technologies, this application has the following advantages:

[0054] The electrically heated fabric provided in this application includes a fiber cloth, on one or both sides of which is provided with an electrically heated film. The electrically heated film has a wave-transparent function and is formed by curing a conductive slurry. The conductive slurry includes resin, dispersant, carbon material, functional compound, and solvent, and the functional compound includes nitrogen-containing compound and / or acidic compound. By adding specific functional compounds to the raw materials for preparing the electrically heated film, the cross-linking reaction between the functional compounds and the resin in the composite material is utilized to effectively improve the interfacial adhesion performance between the electrically heated film and the composite material. This ensures the long-term stability and reliability of the obtained electrically heated fabric and its integrated composite material under extreme operating environments, and it also has a wave-transparent function, making it suitable for application on aircraft surfaces.

[0055] After reading and understanding the accompanying diagrams and detailed descriptions, the other aspects can be understood. Attached Figure Description

[0056] Figure 1 is a schematic cross-sectional view of the electrically heated fabric provided in Example 1;

[0057] Figure 2 is a schematic cross-sectional view of the electrically heated fabric provided in Example 2;

[0058] Among them, 1-fiber cloth, 2-electric heating film. Detailed Implementation

[0059] The technical solution of this application will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely to help understand this application and should not be regarded as specific limitations on this application.

[0060] Information on some of the raw materials involved in the following specific implementation methods is shown below:

[0061] (A) Resin

[0062] Polyurethane resin: purchased from Wanhua Chemical, brand name: 1633;

[0063] Epoxy resin: purchased from Baling Petrochemical, brand name CYD-128;

[0064] Acrylic resin: purchased from Badifu, brand name RD-6755.

[0065] (B) Dispersant

[0066] Polymaleic acid and its derivatives: purchased from BYK GmbH, Germany, brand name BYK-2013.

[0067] (C) Carbon materials

[0068] Carbon nanotubes: median length 50 μm;

[0069] Graphene: Average sheet diameter is 20 μm.

[0070] (D) Functional compounds

[0071] Amine adducts: purchased from Henkel, USA, brand name EPlKURE 8538-Y-68;

[0072] Aromatic polyamine: diaminodiphenylmethane (DDM), purchased from Zhangjiagang Yarui Chemical Co., Ltd.

[0073] Modified fatty amine: purchased from Zhejiang Anbang, brand name AB-HGQ.

[0074] (E) Epoxy resin curing agent: purchased from Baling Petrochemical, brand name CYDHD-583.

[0075] Example 1

[0076] A type of electrically heated fabric, the cross-sectional structure of which is shown in Figure 1, includes a fiber cloth 1 and an electrically heated film 2 disposed on both sides of the fiber cloth 1.

[0077] Among them, fiber cloth 1 is a glass fiber woven fabric with a basis weight of 60g / m². 2 ;

[0078] The thickness of the electric heating film 2 is 2 μm;

[0079] The method for preparing the electrically heated fabric provided in this embodiment includes the following steps:

[0080] (1) Add 1 part by weight of dispersant, 10 parts by weight of carbon nanotubes, 2 parts by weight of amine adduct and 500 parts by weight of water to 20 parts by weight of polyurethane resin and mix. After stirring for 30 minutes, treat in a high-pressure homogenizer of 200 bar for 20 minutes to obtain conductive paste.

[0081] (2) The conductive paste obtained in step (1) is sprayed onto both sides of the fiber cloth and cured at 80°C for 10 minutes to obtain the electrically heated fabric.

[0082] Example 2

[0083] A type of electrically heated fabric, the cross-sectional structure of which is shown in Figure 2, includes a fiber cloth 1 and an electrically heated film 2 disposed on one side of the fiber cloth 1.

[0084] Among them, fiber cloth 1 is a glass fiber woven fabric with a basis weight of 220g / m². 2 ;

[0085] The thickness of the electric heating film 2 is 15 μm;

[0086] The method for preparing the electrically heated fabric provided in this embodiment includes the following steps:

[0087] (1) Add 8 parts by weight of dispersant, 40 parts by weight of carbon nanotubes, 0.5 parts by weight of amine adduct and 800 parts by weight of water to 25 parts by weight of acrylic resin, stir for 30 min, and then process in a high-pressure homogenizer at 200 bar for 20 min to obtain conductive paste.

[0088] (2) The conductive paste obtained in step (1) is sprayed onto both sides of the glass fiber woven fabric and cured at 100°C for 10 minutes to obtain the electrically heated fabric with wave transmission function.

[0089] Example 3

[0090] An electrically heated fabric, having the same structure as in Example 2, includes a fiber cloth and an electrically heated film disposed on one side of the fiber cloth.

[0091] The fiber cloth is a glass fiber woven fabric with a basis weight of 175 g / m². 2 ;

[0092] The thickness of the electric heating film is 0.5 μm;

[0093] The method for preparing the electrically heated fabric provided in this embodiment includes the following steps:

[0094] (1) Add 0.6 parts by weight of dispersant, 2 parts by weight of graphene and 4.5 parts by weight of aromatic polyamine to 28 parts by weight of epoxy resin, stir for 30 minutes and then perform three-roll milling. After milling 5 times, a conductive slurry is obtained.

[0095] (2) Add 7 parts by weight of epoxy resin curing agent to the conductive paste obtained in step (1), scrape it onto one side of the fiber cloth, and cure it at 150°C for 30 minutes to obtain the electric heating fabric.

[0096] Example 4

[0097] An electrically heated fabric with wave-transmitting function is different from Example 1 in that a modified fatty amine is used instead of an amine adduct, while the other structures, substances and preparation methods are the same as in Example 1.

[0098] Example 5

[0099] An electrically heated fabric with wave-transmitting function is different from Example 1 in that it uses pyromellitic dianhydride instead of amine adduct, while the other structures, substances and preparation methods are the same as in Example 1.

[0100] Examples 6-9

[0101] An electrically heated fabric with wave-transmitting function is different from Example 1 in that the amount of amine adduct used is 0.1 parts by weight (Example 6), 5 parts by weight (Example 7), 0.01 parts by weight (Example 8) and 50 parts by weight (Example 9), respectively. The other structures, substances and preparation methods are the same as those in Example 1.

[0102] Comparative Example 1

[0103] An electrically heated fabric, which differs from Example 1 in that no amine adduct is added, but the other structures, substances and preparation methods are the same as in Example 1.

[0104] Performance testing:

[0105] (1) Sheet resistance: measured using a four-probe method;

[0106] (2) Interlaminar shear strength: The electrically heated fabric is placed in the middle layer of the epoxy composite material and co-cured with the epoxy composite material to prepare a composite material sample. Then, the interlaminar fracture toughness of the composite material sample is tested according to the method specified in JC / T 773 "Fiber Reinforced Plastics Short Beam Method for Determination of Interlaminar Shear Strength".

[0107] The electrically heated fabrics provided in Examples 1-9 and Comparative Example 1 were tested according to the above test methods. The test results are shown in Table 1.

[0108] Table 1

[0109] According to the data in Table 1:

[0110] (1) The sheet resistance of the electrically heated fabrics provided in Examples 1 to 7 is 16 to 2430 Ω / □. When integrated with epoxy composite materials, the interlaminar shear strength of the resulting composite material samples is as high as 62 to 76 MPa.

[0111] (2) Comparing the data of Example 1 and Comparative Example 1, it can be seen that when the electric heating fabric is integrated with the epoxy composite material, the electric heating fabric with added functional compounds shows a significant advantage in interlaminar shear strength compared with the sample prepared without the addition of functional compounds (Comparative Example 1).

[0112] (3) Comparing the data of Example 1 and Examples 8-9, it can be seen that if the amount of functional compound added is too low or too high, the interfacial bonding performance will be poor when the electrically heated fabric is integrated with the epoxy composite material, and the interlaminar shear strength will decrease.

[0113] The applicant declares that this application illustrates an electrically heated fabric with wave-transmitting function, its preparation method, and its application through the above embodiments. However, this application is not limited to the above embodiments, meaning that this application does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this application, equivalent substitutions of raw materials for the products of this application, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this application.

Claims

1. An electrically heated fabric, comprising a fiber cloth, wherein an electrically heated film is disposed on one or both surfaces of the fiber cloth, the electrically heated film having wave-transmitting function; The electric heating film is formed by curing a conductive slurry, which includes resin, dispersant, carbon material, functional compound and solvent, and the functional compound includes nitrogen-containing compound and / or acidic compound; The sheet resistance of the electrically heated fabric is 10–3000 Ω / □.

2. The electrically heated fabric according to claim 1, wherein, The fiber cloth includes nonwoven fiber cloth or woven fiber cloth; Preferably, the fiber cloth contains inorganic fibers and / or organic fibers.

3. The electrically heated fabric according to claim 1 or 2, wherein, The thickness of the electric heating film is 0.1–20 μm.

4. The electrically heated fabric according to any one of claims 1 to 3, wherein, The conductive paste comprises the following components by weight:

5. The electrically heated fabric according to any one of claims 1 to 4, wherein, The resin includes thermosetting resins and / or thermoplastic resins; Preferably, the resin includes any one or a combination of at least two of the following: acrylic resin, polyester resin, phenolic resin, epoxy resin, alkyd resin, polyurethane resin, silicone resin, polycarbonate resin, rubber, or polyimide.

6. The electrically heated fabric according to any one of claims 1 to 5, wherein, The carbon material includes any one or a combination of at least two of the following: carbon nanotubes, carbon black, graphene, graphene oxide, or graphite. Preferably, the carbon nanotubes include single-walled carbon nanotubes and / or double-walled carbon nanotubes; Preferably, the median length of the carbon nanotubes is 0.1–1000 μm, more preferably 1–800 μm, and even more preferably 10–500 μm; Preferably, the graphene comprises single-layer graphene and / or multi-layer graphene; Preferably, the average sheet diameter of the graphene and graphene oxide is independently 0.1 to 2000 μm, more preferably 1 to 1000 μm, and even more preferably 5 to 200 μm.

7. The electrically heated fabric according to any one of claims 1 to 6, wherein, The functional compound includes any one or a combination of at least two of aliphatic amines, aromatic amines, organic acid anhydrides, or amine adducts.

8. A method for preparing an electrically heated fabric as described in any one of claims 1 to 7, comprising the following steps: (1) The resin, dispersant, carbon material, functional compound and solvent are mixed to obtain a conductive paste; (2) The conductive paste obtained in step (1) is coated on one or both sides of the fiber cloth and cured to obtain the electrically heated fabric with wave transmission function.

9. The preparation method according to claim 8, wherein, The mixing method described in step (1) includes any one or a combination of at least two of mechanical stirring, ultrasonication, high-pressure homogenization, or three-roll milling; Preferably, the coating method in step (2) includes any one or a combination of at least two of the following: blade coating, spray coating, casting, dip coating, or roller coating.

10. An electric heating element comprising an electric heating fabric and a metal electrode as described in any one of claims 1 to 7.

11. An application of the electric heating element as claimed in claim 10, comprising use on an aircraft surface; Preferably, the application includes radar or antenna surfaces for aircraft.

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