Visible-infrared-radar band compatible stealth composite material and preparation method and application thereof

Abstract

The invention discloses a visible-infrared-radar band compatible stealth composite material as well as a preparation method and application thereof. The composite material comprises a braid layer, a wide-spectrum functional layer and a transparent medium layer, the braid layer comprises a plurality of fibers, and pores are formed between adjacent fibers; the material of the wide-spectrum functional layer comprises metal and / or nitride, and the thickness of the wide-spectrum functional layer is less than a preset thickness to form a discontinuous structure; the transparent dielectric layer covers the surface of the discontinuous structure and forms optical resonance with the discontinuous structure to generate structural color. The fiber structure of the braid layer is utilized to form the broadband spectrum functional layer with a discontinuous structure, and the broadband spectrum functional layer is matched with the dielectric layer to realize colorful structural colors in a visible light range; in the thermal infrared band, the effect of low infrared emissivity is achieved through the reflection effect of the resonant cavity; in a radar wave range, the discontinuous broadband spectrum functional layer cannot effectively reflect radar waves, so that the material has visible, infrared and radar multiband compatible stealth efficiency.

Description

Technical Field

[0001] The present invention relates to the field of wide-band stealth technology, and in particular to a visible-infrared-radar band compatible stealth composite material, a preparation method thereof and applications thereof. Background Art

[0002] With the rapid development of precision guidance and composite detection technology, manned / unmanned equipment may face threats from infrared, radar, visible light and other multi-spectrum detection equipment at the same time. Therefore, single-band stealth materials will be difficult to meet the stealth requirements of complex electromagnetic environments on the battlefield. In order to reduce the possibility of equipment being discovered, the development of visible light, infrared and radar compatible stealth materials is an inevitable trend in the development of stealth technology. Among the many optoelectronic detection technologies, visible light, infrared and radar detection account for 90%. Therefore, stealth technology that can simultaneously counter visible light, infrared and radar is an important means to improve battlefield survivability.

[0003] At present, the existing stealth technology mainly designs stealth materials for one or two of the above three bands, and it is difficult to achieve the compatible stealth effect of three bands: visible light (usually 380-780nm), infrared (usually 2.5-25μm) and radar (usually 8-12 GHz). In the existing technology, the technology that integrates visible light, infrared and radar multi-band joint stealth is mainly composite stealth coating, which combines a coating with wave-absorbing performance and an infrared low-emissivity camouflage coating to obtain a coating with multi-band compatible stealth performance. However, infrared stealth requires the coating to have low absorption and high reflection characteristics for infrared rays, while microwave (radar) stealth requires the coating to have high absorption and low reflection characteristics. It can be seen that the electromagnetic wave reflection characteristics of infrared and radar stealth are contradictory, and it is impossible to achieve infrared radar compatible stealth, and the existing multi-band stealth composite coating is difficult to overcome this inherent contradiction. At the same time, both optical camouflage materials and infrared low-emissivity materials need to be set on the target surface, and the mixture of the two usually significantly affects the overall camouflage effect. Summary of the invention

[0004] In view of the deficiencies in the prior art, the object of the present invention is to provide a visible-infrared-radar band compatible stealth composite material, a preparation method and application thereof.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention includes: In a first aspect, the present invention provides a visible light-thermal infrared-radar band compatible stealth composite material, which comprises a woven layer, a wide spectrum functional layer and a transparent medium layer; The woven layer includes a plurality of fibers, and there are pores between adjacent fibers; the material of the wide-spectrum functional layer includes metal and / or nitride, and the thickness is below a preset thickness, so that the wide-spectrum functional layers attached to the surfaces of the plurality of fibers independently form a discontinuous structure; the transparent medium layer covers the surface of the discontinuous structure and forms an optical resonance with the discontinuous structure to produce structural color.

[0006] In a second aspect, the present invention further provides a method for preparing a visible light-thermal infrared-radar band compatible stealth composite material, which comprises: The surface of the braided layer is plated with metal or nitride by physical sputtering to form a wide spectrum functional layer, and the thickness of the wide spectrum functional layer is controlled to be below a preset thickness; A transparent medium layer is continuously plated on the surface of the wide spectrum functional layer.

[0007] In a third aspect, the present invention also provides application of the above-mentioned visible light-thermal infrared-radar band compatible stealth composite material in wide-band stealth.

[0008] Based on the above technical solution, compared with the prior art, the beneficial effects of the present invention at least include: The technical solution provided by the present invention constructs an optical resonance structure on the woven layer, utilizes the fiber structure of the woven layer to form a wide-spectrum functional layer with a discontinuous structure, and cooperates with the dielectric layer to achieve colorful structural colors in the visible light range; in the thermal infrared band, the effect of low infrared emissivity is achieved through the reflection of the resonant cavity, and the thermal radiation of the object itself is controlled, thereby achieving an infrared stealth effect; in the radar wave range, the discontinuous wide-spectrum functional layer cannot effectively reflect radar waves and cannot be detected, so the stealth effect of radar waves can be achieved. Therefore, the composite material provided by the present invention has visible, infrared and radar multi-band compatible stealth performance, and can also have the characteristics of light weight, flexibility, high strength, breathability, etc., and can be applied to organisms and equipment to meet multi-environment stealth requirements.

[0009] The above description is only an overview of the technical solution of the present invention. In order to enable those skilled in the art to more clearly understand the technical means of the present application and implement them according to the contents of the specification, the following is a description of the preferred embodiments of the present invention in conjunction with detailed drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic structural diagram of a visible light-thermal infrared-radar band compatible stealth composite material provided by a typical implementation case of the present invention; Figure 2 This is a surface photograph of a visible light-thermal infrared-radar band compatible stealth composite material provided by a typical implementation example of the present invention; Figure 3This is an infrared emission spectrum test chart of a visible light-thermal infrared-radar band compatible stealth composite material provided by a typical implementation case of the present invention; Figure 4 It is a radar transmission spectrum test chart of a visible light-thermal infrared-radar band compatible stealth composite material provided by a typical implementation case of the present invention; Figure 5 It is a schematic diagram of the color adjustment spectrum of a visible light-thermal infrared-radar band compatible stealth composite material provided by a typical implementation case of the present invention; Figure 6 This is a surface photograph of a visible light-thermal infrared-radar band compatible stealth composite material provided by another typical embodiment of the present invention; Figure 7 This is an infrared emission spectrum test chart of a visible light-thermal infrared-radar band compatible stealth composite material provided by another typical implementation case of the present invention; Figure 8 This is a radar transmission spectrum test chart of a composite material provided by a typical comparative example of the present invention; Fig. 9 This is an infrared emission spectrum test chart of a composite material provided by another typical comparative example of the present invention. DETAILED DESCRIPTION

[0011] In view of the deficiencies in the prior art, the inventor of this case has proposed the technical solution of the present invention after long-term research and extensive practice. The technical solution, its implementation process and principle will be further explained as follows.

[0012] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0013] Moreover, relational terms such as “first” and “second” are merely used to distinguish one component or method step from another with the same name, but do not necessarily require or imply any such actual relationship or order between these components or method steps.

[0014] like Figure 1 As shown, an embodiment of the present invention provides a visible light-thermal infrared-radar band compatible stealth composite material, which includes a woven layer, a wide spectrum functional layer and a transparent medium layer; the woven layer includes a plurality of fibers, and there are pores between adjacent fibers; the material of the wide spectrum functional layer includes metal and / or nitride, and the thickness is below a preset thickness, so that the wide spectrum functional layers attached to the surfaces of the plurality of fibers independently form a discontinuous structure; the transparent medium layer covers the surface of the discontinuous structure, and forms optical resonance with the discontinuous structure to produce structural color.

[0015] As a typical example, an embodiment of the present invention proposes a fabric with multiple colors, low infrared emissivity and compatible with broadband radar wave transmission characteristics. The surface of the fabric is a coating structure, including a wide-spectrum functional layer and a transparent medium layer. The transparent medium layer is deposited on the wide-spectrum functional layer. The multiple colors are achieved through the thin film interference effect between coatings with different optical parameters, such as jungle green, sandy yellow and other colors. At the same time, the wide-spectrum functional layer has a low emissivity in the infrared band.

[0016] The above-mentioned product is provided in the form of cloth, which can be used for application needs such as biological wear and equipment covering; but not only that, based on the same technical idea, a non-independent cloth product can also be provided, for example, the surface of the device shell itself exposes an outer layer with a woven structure, and then the structure of the above-mentioned composite material is prepared based on the outer layer, which is integrated with the shell to form a self-stealth structure, etc. Various feasible implementation methods are within the protection scope of the present invention.

[0017] In the above technical scheme, a key technical means is to utilize the discontinuous characteristics of the woven fabric, that is, there are gaps between multiple fibers or multiple fibers form a hole, and there is cross-division of fibers in different directions, for example, the warp divides the weft into multiple sections, combined with precise control of the thickness of the wide-spectrum functional layer to achieve independent segmentation of the metal and / or nitride, forming independent discontinuous structures, and different thicknesses have different scattering effects. The discontinuous structure can reduce infrared emission without affecting the structural color. At the same time, the structure does not have a continuous conductive network, so it plays a key role in enhancing the transmission of radar waves.

[0018] Specifically, the composite material can achieve colorful structural colors in the visible light range by constructing optical resonance between a discontinuous structure and a transparent dielectric layer on a fiber weaving basis. At the same time, by controlling the thickness of the dielectric layer, the desired color can be customized for visual stealth. In the thermal infrared region, a low emissivity effect is achieved through a metal / nitride reflective layer with a micro-nano resonant cavity, which controls the thermal radiation of the object itself, thereby achieving an infrared stealth effect. In the radar wave range, the discontinuous wide-band functional layer cannot effectively reflect radar waves and cannot be detected, so a stealth effect against radar waves can be achieved.

[0019] As for the specific structural dimensions, in some embodiments, the fiber diameter of the woven layer is about 80 μm, such as 60-100 μm, and the average pore width between the fibers is about 50 μm, such as 30-70 μm.

[0020] In some embodiments, the preset thickness is a sub-wavelength size, for example, lower than the lower limit of visible light, 380 nm. In some specific implementation cases, the thickness of the wide spectrum functional layer may be significantly lower than the preset thickness, but it is not limited to this range. The specific situation needs to be adjusted according to different materials and deposition methods, so as not to form a large area of ​​continuous wide spectrum functional layer, and to ensure that the wide spectrum functional layer has sufficient thickness to play the corresponding function.

[0021] In the above technical solution, the fiber diameter, average gap width and preset thickness are all factors that significantly affect the size of the discontinuous structure. When the fiber diameter is large (for example, more than 150μm), the size of the individual structure of the discontinuous structure formed is large. When the fiber gap is large (for example, more than 80μm), the intervals between the individual structures of the discontinuous structure are far apart, absorbing or transmitting most of the visible light, thereby affecting the structural color. In addition, the thickness of the wide-spectrum functional layer will also affect the size and spacing. When it is large, the individual structure will increase and the interval will decrease. When its size is too large, for example, the inventor has observed that it is greater than 300nm through practice, it often leads to the merging of multiple discontinuous structures to form a functional layer that is biased towards continuity, triggering full-band reflection, and obviously losing radar high transmittance. Therefore, in specific applications, the above parameters should be reasonably controlled.

[0022] In some embodiments, the thickness of the wide spectrum functional layer is 20-300nm. Of course, in addition to having an upper limit, the thickness of the wide spectrum functional layer should not be too thin. The thickness determines the thermal infrared and radar wave stealth effects. The thickness is different on different cloth bases, depending on whether the metal layer is continuous and whether a continuous conductive network is formed. An overly thick metal layer will form a continuous film with excellent conductivity, thereby reflecting radar waves and being monitored. On the other hand, the thickness of the layer cannot be less than 30nm, otherwise it will affect its infrared reflection effect. When the thickness is reduced to 20nm, the infrared reflection effect is lost to a greater extent, and it is difficult to achieve infrared stealth.

[0023] In addition, regarding the transparent medium layer, in some embodiments, the thickness of the transparent medium layer is 50-400nm, and the structural color changes with the thickness of the transparent medium layer. The thickness of the transparent medium layer can be adjusted in a wide range, and its thickness can be freely adjusted to form structural colors of different colors. Even in the preferred embodiment, different thicknesses of the transparent medium layer can be set in different areas to achieve a camouflage effect.

[0024] Regarding the material of each layer, in some embodiments, the metal includes any one of gold, silver, copper, aluminum, tungsten, and titanium, or a combination of two or more thereof; the nitride includes any one of titanium nitride and zirconium nitride, or a combination of two thereof, and is not limited thereto.

[0025] In some embodiments, the transparent medium layer includes any one or a combination of two or more of aluminum oxide, titanium oxide, tungsten oxide, zinc oxide, zirconium oxide, and niobium oxide, but is not limited thereto.

[0026] In some embodiments, the fibers may include commercially available conventional finished fibers such as nylon, polyester, acrylic, nylon, spandex, polypropylene, and vinylon, as well as a variety of advanced fibers that meet radar transmission characteristics.

[0027] The above materials are various materials that the inventors of the present invention have used in long-term attempts, and all of them can achieve similar three-band stealth effects. However, this does not mean that the materials that can achieve this effect are limited to the materials listed above.

[0028] In addition, in some embodiments, a transparent protective layer is also covered on the surface of the transparent medium layer, and the material of the transparent protective layer is a radar wave transparent material. In some preferred schemes, a transparent protective layer can be covered, such as a silicon dioxide layer or a polymer layer, which can play a protective role without affecting the structural color.

[0029] A second aspect of the embodiments of the present invention further provides a method for preparing the visible light-thermal infrared-radar band compatible stealth composite material provided in any of the above embodiments, which comprises the following steps: The surface of the braided layer is plated with metal or nitride by physical sputtering to form a wide spectrum functional layer, and the thickness of the wide spectrum functional layer is controlled to be below a preset thickness; A transparent medium layer is continuously plated on the surface of the wide spectrum functional layer.

[0030] In some embodiments, the physical sputtering method includes any one or a combination of two or more of magnetron sputtering, vacuum evaporation, spin coating, and spray coating, but is not limited thereto.

[0031] As a typical example, the method for preparing the stealth fabric with visible multi-color, low infrared emissivity and radar-transparent compatibility provided by the present invention comprises the following steps: S1: With fabric as substrate, a wide spectrum functional layer is prepared on its surface by physical vapor deposition methods such as magnetron sputtering and evaporation. By controlling the thickness of the film layer, low infrared emissivity is obtained while ensuring radar wave transmission properties; S2: A transparent dielectric layer is deposited on the surface of the wide-spectrum functional layer by magnetron sputtering; the film thickness is then adjusted according to the desired color, and a variety of colors are obtained by using the thin film interference effect.

[0032] Furthermore, an embodiment of the present invention also provides an application of the visible light-thermal infrared-radar band compatible stealth composite material provided by any of the above-mentioned embodiments in wide-band stealth.

[0033] The visible light-thermal infrared-radar band compatible stealth composite material provided by the present invention can be realized by a continuous coating process, and has the advantage of large-area processing. The wide-spectrum functional layer and the transparent medium layer are deposited on the flexible base fabric in sequence, and the compatibility of low infrared emissivity and broadband radar wave transmission can be achieved by precise thickness control. The wavelength selective interference between the transparent medium layer and the visible light band can be used to achieve a wide color gamut and high-saturation visible color of the fabric. At the same time, the infrared lossless medium layer will not affect the low emissivity of the wide-spectrum functional layer, thereby achieving the application effect of visible light-thermal infrared-microwave wide-band compatible stealth.

[0034] The technical solution of the present invention is further described in detail below through several embodiments and in conjunction with the accompanying drawings. However, the selected embodiments are only used to illustrate the present invention, and do not limit the scope of the present invention.

[0035] Example 1 This embodiment provides a visible light-thermal infrared-radar wave wide band compatible fabric, such as Figure 1 As shown, it includes a transparent medium layer A, a wide spectrum functional layer B, and a porous woven base layer C arranged in sequence from top to bottom. The porous woven base layer C is made of nylon fabric with a thickness of about 50 μm and a pore size of about 50 μm, providing support, breathability and basic radar wave penetration performance.

[0036] The transparent medium layer A is a TiO2 layer with a thickness of about 130 nm. The wide spectrum functional layer is a metal Ti with a thickness of about 100 nm, which is in-situ deposited on the porous woven base layer C and also has a porous structure.

[0037] The method for preparing the visible light-thermal infrared-radar wave wide-band compatible fabric comprises: S1: Select commodity fabric base with high strength and breathability; S2: depositing a metal layer and a transparent dielectric layer on the base fabric in sequence by magnetron sputtering; This example produces a visible light-thermal infrared-microwave wide-band compatible fabric such as Figure 2 The visual color shown is earthy yellow. For the effect of low emissivity in the infrared band, please refer to Figure 3 As shown, the infrared emissivity at 10μm wavelength is less than 0.3, and the microwave band high transmittance test is shown in Figure 4 shown.

[0038] Obviously, the visible light-thermal infrared-radar wave wide band compatible fabric provided in this embodiment has excellent three-band stealth capability. In addition, by adjusting the thickness of the transparent medium layer, it can be adjusted between different colors. For details, please refer to Figure 5 shown.

[0039] Example 2 This embodiment provides a visible light-thermal infrared-microwave wide-band compatible fabric, which is similar to Embodiment 1. It includes a transparent medium layer, a wide spectrum functional layer, and a porous woven base layer arranged in sequence from top to bottom.

[0040] The difference between the two is: The wide spectrum functional layer adopts a double-layer structure, which is composed of about 50nm of metallic copper and 100nm of aluminum. Compared with the single-layer metal in Example 1, the double-layer structure used in this embodiment does not affect the low infrared emissivity, but enhances the interference effect and achieves highly saturated visible colors.

[0041] A method for preparing a visible light-thermal infrared-microwave broadband compatible fabric comprises: S1: Select commodity fabric base with high strength and breathability; S2: using magnetron sputtering to sequentially deposit a wide spectrum functional layer and a transparent dielectric layer on the porous woven base layer; The visible light-thermal infrared-microwave broadband compatible fabric prepared in this embodiment is visually green, see Figure 6 As shown; the infrared emissivity at a wavelength of 10 μm is less than 0.1, which is lower than that of Example 1. For test results, see Figure 7 shown.

[0042] Example 3 This embodiment provides a visible light-thermal infrared-microwave wide-band compatible fabric, which is similar to embodiment 1. The difference is that a silicon dioxide layer is added on the top transparent medium layer, and its thickness can be adjusted appropriately, which will not significantly affect the performance of the visible, infrared, and microwave bands, but enhances the surface stability of the visible light-thermal infrared-radar wide-band compatible stealth fabric, such as wear resistance, water and oxygen resistance, etc. This implementation is also applicable to embodiment 2.

[0043] Comparative Example 1-1 This comparative example is substantially the same as Example 1, except that: The magnetron sputtering time was extended to increase the thickness of the broadband functional layer to 400 nm.

[0044] The functional layer prepared in this comparative example does not have the discontinuous structure characteristics of the wide-spectrum functional layer prepared in Example 1. Due to its thick deposition thickness, the coatings between multiple fibers are combined to form a continuous structure, which loses the radar transmission characteristics.

[0045] Specifically, the transparent medium layer A is a TiO2 layer with a thickness of about 130 nm. The wide spectrum functional layer is a metal Ti with a thickness of about 400 nm, which is in-situ deposited on the porous woven base layer C.

[0046] The method for preparing the visible light-thermal infrared-radar wave wide-band compatible fabric comprises: S1: Select commodity fabric base with high strength and breathability; S2: depositing a metal layer and a transparent dielectric layer on the base fabric in sequence by magnetron sputtering; The microwave band test of a kind of cloth prepared in this comparative example is shown in Figure 8 As shown, it is obvious that the cloth provided in this comparative example does not have high microwave permeability.

[0047] Comparative Example 1-2 This comparative example is substantially the same as Example 1, except that: The time of magnetron sputtering was shortened and the thickness of the broadband functional layer was reduced to 15 nm.

[0048] The fabric prepared in this comparative example does not have low infrared emissivity. Its emission spectrum is shown in Fig. 9 As shown, no infrared stealth function is presented.

[0049] Comparative Example 2-1 This comparative example is substantially the same as Example 1, except that: Replace nylon cloth with nylon film.

[0050] Since the substrate does not have a woven structure, after the metal layer is deposited, a complete continuous metal layer is formed, which is similar to the result of comparative example 1-1 and completely loses the radar transmission property.

[0051] Comparative Example 2-2 This comparative example is substantially the same as Example 1, except that: Adjust the weaving parameters of the nylon fabric so that it is tightly woven, with the fibers in close contact and almost no noticeable gaps.

[0052] Since the substrate does not have a porous structure, after the metal layer is deposited, a nearly continuous metal layer is formed, which is similar to the result of comparative example 1-1 and completely loses the radar transmission property.

[0053] Based on the above embodiments and comparative examples, it can be clearly seen that the technical solution provided by the embodiments of the present invention constructs an optical resonance structure on the woven layer, utilizes the fiber structure of the woven layer to form a wide-spectrum functional layer with a discontinuous structure, and cooperates with the dielectric layer to achieve colorful structural colors in the visible light range; in the thermal infrared band, the effect of low infrared emissivity is achieved through the reflection of the resonant cavity, and the thermal radiation of the object itself is controlled, thereby achieving an infrared stealth effect; in the radar wave range, the discontinuous wide-spectrum functional layer cannot effectively reflect radar waves and cannot be detected, so the stealth effect of radar waves can be achieved. Therefore, the composite material provided by the present invention has visible, infrared and radar multi-band compatible stealth performance, and at the same time has the characteristics of light weight, flexibility, high strength, breathability, etc., and can be applied to organisms and equipment to meet multi-environment stealth requirements.

[0054] It should be understood that the above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A visible light-thermal infrared-radar band compatible stealth composite material, characterized in that: It includes a woven layer, a wide spectrum functional layer and a transparent medium layer; The woven layer includes a plurality of fibers, and there are pores between adjacent fibers; the material of the wide-spectrum functional layer includes metal and / or nitride, and the thickness is below a preset thickness, so that the wide-spectrum functional layers attached to the surfaces of the plurality of fibers independently form a discontinuous structure; the transparent medium layer covers the surface of the discontinuous structure and forms an optical resonance with the discontinuous structure to produce structural color.

2. The visible light-thermal infrared-radar band compatible stealth composite material according to claim 1, characterized in that: The fiber diameter of the braided layer is 60-100 μm, and the average pore width between the fibers is 30-70 μm.

3. According to the visible light-thermal infrared-radar band compatible stealth composite material according to claim 1, the preset thickness is a sub-wavelength size.

4. The visible light-thermal infrared-radar band compatible stealth composite material according to claim 3, characterized in that: The thickness of the broadband functional layer is 20-300 nm.

5. The visible light-thermal infrared-radar band compatible stealth composite material according to any one of claims 1 to 4, characterized in that: The thickness of the transparent medium layer is 50-400 nm, and the structural color changes with the thickness of the transparent medium layer.

6. The visible light-thermal infrared-radar band compatible stealth composite material according to claim 1, characterized in that: The metal includes any one of gold, silver, copper, aluminum, tungsten and titanium or a combination of two or more thereof; the nitride includes any one of titanium nitride and zirconium nitride or a combination of two thereof; And / or, the transparent medium layer includes any one of aluminum oxide, titanium oxide, tungsten oxide, zinc oxide, zirconium oxide, and niobium oxide, or a combination of two or more thereof.

7. The visible light-thermal infrared-radar band compatible stealth composite material according to claim 1, characterized in that: The surface of the transparent medium layer is also covered with a transparent protective layer, and the material of the transparent protective layer is a radar wave-transparent material.

8. The method for preparing the visible light-thermal infrared-radar band compatible stealth composite material according to any one of claims 1 to 7, characterized in that: include: The surface of the braided layer is plated with metal or nitride by physical sputtering to form a wide spectrum functional layer, and the thickness of the wide spectrum functional layer is controlled to be below a preset thickness; A transparent medium layer is continuously plated on the surface of the wide spectrum functional layer.

9. The preparation method according to claim 8, characterized in that: The physical sputtering method includes any one or a combination of two or more of magnetron sputtering, vacuum evaporation, spin coating, and spray coating.

10. Application of the visible light-thermal infrared-radar band compatible stealth composite material as described in any one of claims 1 to 7 in wide-band stealth.

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