Broadband optical stealth material applied to bare earth surface environment and preparation method of broadband optical stealth material

Abstract

The invention relates to the technical field of functional materials, and discloses a broadband optical stealth material applied to an exposed surface environment and a preparation method of the broadband optical stealth material applied to the exposed surface environment. Comprising the following components in parts by weight: 100-140 parts of synthetic resin, 10-30 parts of a crosslinking aid, 46-60 parts of a metal oxide pigment and 3-8 parts of a compound aid, the preparation method is used for preparing the broadband optical stealth material and comprises the following steps: uniformly mixing the weighed synthetic resin, crosslinking aid, metal oxide pigment and composite aid to form a pre-mixture; and heating and curing the pre-mixture to obtain the broadband optical stealth material. The broadband optical stealth material disclosed by the invention can simulate a natural spectrum of an exposed earth surface environment in a range of 400-2000 nm at high precision, and the broadband optical stealth material is difficult to identify by a hyperspectral detection technology.

Description

Technical Field

[0001] This invention belongs to the field of functional materials technology, specifically relating to broadband optical stealth materials for use in exposed surface environments and their preparation methods. Background Technology

[0002] Optical stealth materials are widely used in military equipment camouflage and special facility concealment because they can reduce the detectability of targets. Optical stealth materials achieve visual invisibility by mimicking the color of the background environment, thereby deceiving observers.

[0003] Currently, hyperspectral detection technology is developing rapidly. By acquiring spectral information of a target in tens or even hundreds of consecutive narrow bands, hyperspectral detection technology can accurately analyze the material composition and spectral characteristics of the target, offering higher spectral resolution and richer spectral information dimensions. The typical operating band of hyperspectral detection technology is 400–2500 nm, covering the visible band of 400–780 nm and the near-infrared band of 780–2500 nm.

[0004] However, optical stealth materials are only effective in the visible light band. For the near-infrared band, invisible to the human eye, the high-precision spectral resolution of hyperspectral detection technology poses a significant challenge. While the target object camouflaged by optical stealth materials is difficult for the naked eye to detect in terms of its difference from the surrounding environment, the high resolution of hyperspectral detection technology makes these differences easily discernible by detecting the spectra of the target object and its surrounding environment. This is especially true in bare surface environments lacking vegetation, such as the Gobi Desert and other arid lands. Differences in climate, topography, and moisture among different background environments result in variations in the composition of environmental materials, leading to differences in their characteristic spectra. The spectral characteristics of the natural background in bare surface environments are complex and variable, making it difficult for optical stealth materials to match the background spectrum across a wide wavelength range, thus making the target easily identifiable by hyperspectral detection equipment. Summary of the Invention

[0005] To address the shortcomings of the prior art, the first aspect of this application aims to provide a broadband optical stealth material applicable to exposed surface environments. This material can simulate the reflection spectrum of soil in the range of 400-2000 nm in exposed surface environments and improve the similarity between the reflection spectrum of the optical stealth material and the reflection spectrum of the background environment, thereby achieving a good optical stealth effect under the detection of hyperspectral detection technology.

[0006] The second aspect of this application aims to provide a method for preparing a broadband optical stealth material applicable to exposed surface environments, which can prepare an optical stealth material that is adaptable to a wide range of wavelengths and has excellent optical stealth performance.

[0007] The technical effects to be achieved by this invention are realized through the following technical aspects: In a first aspect, the present invention provides a broadband optical stealth material for use in exposed ground environments, comprising the following components by weight: 100-140 parts of synthetic resin, 10-30 parts of crosslinking agent, 46-60 parts of metal oxide pigment, and 3-8 parts of composite agent.

[0008] In some implementations, the metal oxide pigment comprises the following components by weight: 80-140 parts of yellow pigment, 100-150 parts of white pigment, 10-50 parts of black pigment, 0-10 parts of red pigment, and 0-5 parts of brown pigment.

[0009] In some implementations, the yellow pigment is one or more of Fe2O3·H2O, SrCrO4, PbCrO4, CaCrO4, NiO·Sb2O5·20TiO2; The white pigment is one or more of TiO2, ZnO, Sb2O3, and TiO2·2H2O; The black pigment is one or more of MnO2, Mn2O3, FeO, Fe3O4, CuO, and β-HgS; The red pigment is one or more of Fe2O3, Pb3O4, Co(OH)2, α-HgS, and Sb2S3; The brown pigment is one or more of Cr2O3·Sb2O3·31TiO2, xFe2O3·yFeO·zH2O, MgO·Fe2O3, Cr2O3·Sb2O3·31TiO2, and xZnO·yFe2O3·zCr2O3.

[0010] In some implementations, the synthetic resin is one or more of alkyd resin, polyester resin, polyurethane resin, epoxy resin, acrylic resin, and silicone resin.

[0011] In some implementations, the crosslinking aid is one or more of isophorone diamine, maleic anhydride, methyltetrahydrophthalic anhydride, triethylenetetramine, benzoyl peroxide, di-tert-butyl peroxide, cyclohexanone peroxide, polyether polyol, polyester polyol, cobalt naphthenate, 3-aminopropylmethoxysilane, dibutyltin dilaurate, etc.

[0012] In some implementations, the composite additive includes the following components by weight: 2-7 parts of antifungal agent, 5-10 parts of UV stabilizer, and 3-5 parts of antistatic agent.

[0013] In some implementations, the UV stabilizer is one or more of titanium dioxide, cerium dioxide, phenyl salicylate, bis-2,2,6,6-tetramethylpiperidinol sebacate, and 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole.

[0014] In some implementations, the antistatic agent is one or more of tin dioxide, graphene, conductive carbon black, sodium dodecylbenzenesulfonate, and dodecyltrimethylammonium chloride.

[0015] Secondly, the present invention provides a method for preparing a broadband optical stealth material for use in exposed surface environments, which is used to prepare the broadband optical stealth material for use in exposed surface environments as described above, comprising the following steps: mixing weighed synthetic resin, crosslinking agent, metal oxide pigment and composite agent evenly to form a premix; heating and curing the premix to obtain the broadband optical stealth material.

[0016] In some implementations, the heating and curing temperature is 50~100℃, and the heating time is 20~500 min.

[0017] In summary, the present invention has at least the following advantages: 1. The broadband optical stealth material provided by this invention, applicable to exposed surface environments, comprises a three-dimensional network structure formed by cross-linking synthetic resin with metal oxide pigments through the action of cross-linking agents and composite additives. This optimizes the absorption capacity of the broadband optical stealth material for specific wavelengths of light, as well as its reflection characteristics for visible and near-infrared light. The broadband optical stealth material simulates the natural environmental spectrum of exposed surface environments and exhibits high accuracy in simulating the background spectrum across a broadband band of 400–2000 nm. This enables it to accurately identify visible and near-infrared bands using hyperspectral detection technology, making it suitable for natural backgrounds with complex and varied spectral characteristics.

[0018] 2. The method for preparing broadband optical stealth materials for use on exposed ground environments provided by this invention involves uniformly mixing synthetic resin, crosslinking agent, metal oxide pigment and composite additive, followed by heating and curing. The method for preparing broadband optical stealth materials is simple, produces less environmental pollution, and can produce broadband optical stealth materials that are difficult for hyperspectral detection equipment to identify. Attached Figure Description

[0019] Figure 1 This is a graph showing the spectral reflectance test results of the broadband optical stealth material and the exposed ground environment in Embodiment 1 of the present invention.

[0020] Figure 2 This is a graph showing the spectral reflectance test results of the broadband optical stealth material and the exposed surface environment in Embodiment 2 of the present invention.

[0021] Figure 3 This is a graph showing the spectral reflectance test results of the broadband optical stealth material and the exposed ground environment in Embodiment 3 of the present invention.

[0022] Figure 4 The figure shows the spectral reflectance test results of the broadband optical stealth material and the exposed ground environment in Comparative Example 1 of this invention. Detailed Implementation

[0023] To facilitate understanding of the present invention, a more comprehensive description will be provided below with reference to specific embodiments. Preferred embodiments are given herein. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0024] Before further describing in more detail the various embodiments of the compounds / compositions and methods of this disclosure through exemplary descriptions, examples, and results, it should be understood that the embodiments of this disclosure are not limited in application to the details of the methods and compositions described below. The descriptions provided herein are for illustrative purposes only and are not intended to be interpreted in a limiting sense. The inventive concept of this disclosure can have other embodiments or can be practiced or implemented in various ways. Therefore, the language used herein is intended to give the broadest scope and meaning; and the embodiments are intended to be exemplary, not exhaustive, and are not intended to limit this disclosure to these particular embodiments. Moreover, it should be understood that the wording and terminology used herein are for descriptive purposes and should not be considered limiting unless otherwise stated. Furthermore, numerous specific details are set forth in the following detailed description to provide a more thorough understanding of this disclosure.

[0025] However, it will be apparent to those skilled in the art that embodiments of this disclosure can be practiced without these specific details. In other instances, features well-known to those skilled in the art have not been described in detail to avoid unnecessary complexity. It is intended that all substitutions, replacements, modifications, and equivalents that are apparent to those skilled in the art are included within the scope of this disclosure. Based on this disclosure, all compounds / compositions disclosed herein, their preparation methods, applications, and uses can be prepared and implemented without excessive experimentation.

[0026] Therefore, although the compounds / compositions and methods of this disclosure have been described with reference to specific embodiments, it will be apparent to those skilled in the art that variations may be made to the formulations, compounds or compositions and / or methods, as well as the steps or sequence of steps of the methods described herein, without departing from the spirit and scope of the inventive concept of this disclosure.

[0027] As used herein, any reference to "an embodiment" or "an embodiment" means that a particular element, feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. The phrase "in an embodiment" appearing in multiple places throughout the specification does not necessarily refer to the same embodiment.

[0028] Unless otherwise defined herein, scientific and technical terms used in connection with this disclosure shall have the meanings commonly understood by one of ordinary skill in the art. Furthermore, unless the context requires otherwise, singular terms shall include plural forms, and plural terms shall include singular forms.

[0029] The following provides a further detailed description of this application.

[0030] The broadband optical stealth material of the present invention, applicable to bare surface environments, comprises the following components by weight: 100-140 parts of synthetic resin, 10-30 parts of crosslinking agent, 46-60 parts of metal oxide pigment, and 3-8 parts of composite agent.

[0031] In a preferred embodiment, the metal oxide pigment comprises the following components by weight: 80-140 parts of yellow pigment, 100-150 parts of white pigment, 10-50 parts of black pigment, 0-10 parts of red pigment, and 0-5 parts of brown pigment.

[0032] Specifically, the yellow pigment is one or more of Fe2O3·H2O, SrCrO4, PbCrO4, CaCrO4, NiO·Sb2O5·20TiO2, such as a yellow pigment being SrCrO4, CaCrO4, or a mixture of PbCrO4 and CaCrO4.

[0033] The white pigment is specifically one or more of TiO2, ZnO, Sb2O3, and TiO2·2H2O, such as a white pigment being a mixture of TiO2, Sb2O3, or ZnO and TiO2·2H2O. The black pigment is specifically one or more of MnO2, Mn2O3, FeO, Fe3O4, CuO, and β-HgS, such as a mixture of Mn2O3, FeO, or MnO2 and CuO. Red pigments are specifically one or more of Fe2O3, Pb3O4, Co(OH)2, α-HgS, and Sb2S3, such as red pigments being a mixture of Pb3O4, Co(OH)2, or Sb2S3 and Fe2O3. Brown pigments are one or more of the following: Cr2O3·Sb2O3·31TiO2, xFe2O3·yFeO·zH2O, MgO·Fe2O3, Cr2O3·Sb2O3·31TiO2, and xZnO·yFe2O3·zCr2O3, such as brown pigments being Cr2O3·Sb2O3·31TiO2 or xZnO·yFe2O3·zCr2O3.

[0034] Furthermore, the particle size of the metal oxide pigment is 1~25μm.

[0035] Yellow, white, black, red, and brown pigments are blended together. Metal oxide pigments enable broadband optical cloaking materials to achieve reflectivity similar to soil in a bare surface environment by controlling the reflection and absorption characteristics within the 400-2000 nm wavelength range. Target objects camouflaged by broadband optical cloaking materials exhibit brightness and color similar to the background environment under hyperspectral detection technology. Broadband optical cloaking materials successfully simulate the natural environmental spectrum of a bare surface environment.

[0036] In preferred embodiments, the synthetic resin is one or more selected from alkyd resin, polyester resin, polyurethane resin, epoxy resin, acrylic resin, and silicone resin. In some specific embodiments, the crosslinking aid is one or more selected from isophorone diamine, maleic anhydride, methyltetrahydrophthalic anhydride, triethylenetetramine, benzoyl peroxide, di-tert-butyl peroxide, cyclohexanone peroxide, polyether polyol, polyester polyol, cobalt naphthenate, 3-aminopropylmethoxysilane, and dibutyltin dilaurate. Specifically, the synthetic resin is an alkyd resin, and the crosslinking aid is 3-aminopropylmethoxysilane. Those skilled in the art can select the appropriate crosslinking aid according to the actual synthetic resin chosen, which is beneficial for the metal oxide pigment to form an electronic band structure within the synthetic resin, thereby achieving the simulation of the natural background spectrum.

[0037] In a preferred embodiment, the composite additive includes the following components in parts by weight: 2-7 parts of antifungal agent, 5-10 parts of UV stabilizer, and 3-5 parts of antistatic agent.

[0038] In some specific embodiments, the antifungal agent is one or more of copper oxide, zinc pyrithione, dodecyl dimethyl benzyl ammonium chloride, tributyltin oxide, and iodopropynyl carbamate; The UV stabilizer is one or more of titanium dioxide, cerium dioxide, phenyl salicylate, bis-2,2,6,6-tetramethylpiperidinol sebacate, and 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole; The antistatic agent is one or more of tin dioxide, graphene, conductive carbon black, sodium dodecylbenzenesulfonate, and dodecyltrimethylammonium chloride, which helps to extend the service life of broadband optical stealth materials. When broadband optical stealth materials are coated on fabric substrates, they can be used in complex natural environments.

[0039] The present invention discloses a method for preparing a broadband optical stealth material for use on exposed ground environments, comprising the following steps: uniformly mixing weighed synthetic resin, crosslinking agent, metal oxide pigment, and composite additive to form a premix; and heating and curing the premix to obtain the broadband optical stealth material. In a preferred embodiment, the heating and curing temperature is 50~100℃, such as 50℃, 80℃, 85℃, 90℃, or 100℃, and the heating time is 20~500 min, such as 20 min, 70 min, 100 min, 200 min, or 500 min.

[0040] Example 1: A broadband optical stealth material for use in exposed surface environments comprises the following components by weight: 130 parts polyurethane resin, 150 parts polyether polyol, 50 parts metal oxide pigment, and 6 parts composite additives.

[0041] The metal oxide pigment comprises the following components in parts by weight: 100 parts SrCrO4, 135 parts ZnO, 30 parts β-HgS, 4 parts Pb3O4, and 2 parts xFe2O3·yFeO·zH2O.

[0042] The composite additive comprises the following components by weight: 3 parts dodecyl dimethyl benzyl ammonium chloride, 6 parts phenyl salicylate, and 5 parts sodium dodecylbenzene sulfonate.

[0043] The preparation method includes the following steps: uniformly mixing polyurethane resin, polyether polyol, metal oxide pigment and composite additive to obtain a mixture; pouring the mixture into a mold; and heating and curing at 70°C for 300 min to obtain a broadband optical stealth material.

[0044] Example 2 A broadband optical stealth material for use in exposed surface environments comprises the following components by weight: 125 parts epoxy resin, 13 parts triethylenetetramine, 58 parts metal oxide pigment, and 5 parts composite additives.

[0045] The metal oxide pigment comprises the following components in parts by weight: 100 parts Fe2O3·H2O, 120 parts ZnO, 25 parts MnO2, 5 parts α-HgS, and 3 parts MgO·Fe2O3.

[0046] The composite additive includes the following components by weight: 4 parts zinc pyridinethione, 6 parts phenyl salicylate, and 3 parts graphene.

[0047] The preparation method includes the following steps: uniformly mixing epoxy resin, triethylenetetramine, metal oxide pigment and composite additives to obtain a mixture; pouring the mixture into a mold; and heating and curing at 60 °C for 240 min to obtain a broadband optical stealth material.

[0048] Example 3 The difference from Example 1 is that SrCrO4 is replaced with PbO and β-HgS is replaced with CuCr2O4 in the metal oxide pigment.

[0049] Comparative Example 1 The difference from Example 1 is that the broadband optical stealth material includes the following components by weight: 140 parts epoxy resin, 25 parts triethylenetetramine, 75 parts metal oxide pigment, and 10 parts composite additives.

[0050] Application Example 1 The following are the steps for preparing a flame-retardant coated fabric using the broadband optical stealth material from Example 1: Step 1: Take a clean woven glass fiber cloth as the substrate. The thickness of the substrate is 100 μm. Apply the premixes prepared in Examples 1 and 2 and Comparative Examples 1 and 2 to the surface of the substrate by scraping. The coating thickness is 300 μm. Step 2: Heat the substrate coated with the mixture to 70°C and keep it at that temperature for 90 minutes to allow the premix to cure. Step 3: After cooling the material obtained in Step 2 to room temperature, apply the premixes prepared in Examples 1 and 2 and Comparative Examples 1 and 2 to the side of the substrate that is not coated with the premix by scraping, with a coating thickness of 300 μm. Step 4: Heat the material obtained from Step 3 to 70°C and hold for 90 minutes to allow the premix to solidify, thus obtaining a coated fabric based on a broadband optical stealth material for use on exposed ground environments.

[0051] Specifically, the coated fabric, prepared by using flame-retardant fiberglass cloth as the substrate, exhibits excellent flame-retardant properties. When exposed to an open flame, the portion near the flame will melt and ignite, but the fire will not spread; once the fire source is removed, the ignited portion of the coated fabric will extinguish rapidly within 3 seconds.

[0052] Application Example 2 The application of the broadband optical stealth material as a coating based on Example 1 follows these steps: Step 1: Mix the weighed synthetic resin, crosslinking agent, metal oxide pigment and composite agent evenly to obtain a premix; Step 2: Apply the premix prepared in Step 1 to the surface of the object to be covered, such as the surface of an aluminum plate, with a coating thickness of 300 μm; Step 3: Heat the object coated with the premixed material from Step 2 at 50 °C for 150 min to cure it. The coating is now complete.

[0053] Spectral reflectance test The similarity between the reflection spectra of the broadband optical stealth materials prepared in Examples 1 and 2, and Comparative Examples 1 and 2, and the reflection spectra of the exposed ground environment was evaluated by normalized similarity.

[0054] The reflectance spectra of broadband optical stealth materials and exposed soil in the 400–2000 nm range were measured using a UV-Vis-NIR spectrophotometer. The similarity between the reflectance spectra of the broadband optical stealth materials and the reflectance spectra of exposed soil was assessed using a normalized similarity method, calculated as follows: Where i is the wavelength of light, This represents the reflectivity of a broadband optical stealth material at wavelength i. This represents the reflectance of soil in a bare surface environment at wavelength i. It is calculated using the above formula. and The cosine of the angle between two vectors (cosθ) is used for quantization. and The similarity between the two was then assessed to evaluate the similarity between the reflection spectra of broadband optical stealth materials and the reflection spectra of soil in exposed ground environments. and The more similar two vectors are, the closer cosθ is to 100%; conversely, the less similar two vectors are, the closer cosθ is to 0.

[0055] See Figure 1 and Figure 2 The spectral reflectance of the broadband optical stealth materials prepared in Examples 1 and 2 is highly similar to that of exposed surface soil in the range of 400–2000 nm. Specifically, the normalized similarity of the broadband optical stealth material prepared in Example 1 reaches 99.92%, and that in Example 2 reaches 99.88%. These broadband optical stealth materials can accurately simulate the natural spectrum of exposed surface environments. Compared to traditional optical stealth materials, they can achieve high-precision simulation within a wide wavelength range of 400–2000 nm, making the camouflaged target difficult to identify by hyperspectral detection equipment.

[0056] See Figure 3 The similarity between the reflection spectrum of the broadband optical stealth material prepared in Example 3 and the reflection spectrum of bare soil is lower than that in Examples 1 and 2. This shows that the selection of the types of pigments in the metal oxide pigments affects the absorption capacity of the broadband optical stealth material for specific wavelengths of light, as well as its reflection characteristics for visible and near-infrared light, and thus affects the simulation accuracy of the reflection spectrum of the broadband optical stealth material on the reflection spectrum of bare soil.

[0057] See Figure 4 The difference between the reflection spectrum of the broadband optical stealth material prepared in Comparative Example 1 and the reflection spectrum of the bare surface soil is significant. The spectral reflectance of the broadband optical stealth material is significantly lower than that of the bare surface soil, and the difference in reflectance becomes more pronounced with increasing wavelength. The ratio of each component in the broadband optical stealth material affects its reflection and light absorption characteristics.

[0058] The above description is merely an example and illustration of the structure of this invention, and while the description is specific and detailed, it should not be construed as limiting the scope of this invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this invention, and these obvious substitutions all fall within the protection scope of this invention.

Claims

1. A broadband optical stealth material for use in exposed surface environments, characterized in that, It includes the following components by weight: 100-140 parts synthetic resin, 10-30 parts crosslinking agent, 46-60 parts metal oxide pigment, and 3-8 parts composite agent.

2. The broadband optical stealth material for use in exposed surface environments according to claim 1, characterized in that, The metal oxide pigment comprises the following components by weight: 80-140 parts of yellow pigment, 100-150 parts of white pigment, 10-50 parts of black pigment, 0-10 parts of red pigment, and 0-5 parts of brown pigment.

3. The broadband optical stealth material for use in exposed surface environments according to claim 2, characterized in that, The yellow pigment is one or more of Fe2O3·H2O, SrCrO4, PbCrO4, CaCrO4, NiO·Sb2O5·20TiO2; The white pigment is one or more of TiO2, ZnO, Sb2O3, and TiO2·2H2O; The black pigment is one or more of MnO2, Mn2O3, FeO, Fe3O4, CuO, and β-HgS; The red pigment is one or more of Fe2O3, Pb3O4, Co(OH)2, α-HgS, and Sb2S3; The brown pigment is one or more of Cr2O3·Sb2O3·31TiO2, xFe2O3·yFeO·zH2O, MgO·Fe2O3, Cr2O3·Sb2O3·31TiO2, and xZnO·yFe2O3·zCr2O3.

4. The broadband optical stealth material for use in exposed surface environments according to claim 1, characterized in that, The synthetic resin is one or more of alkyd resin, polyester resin, polyurethane resin, epoxy resin, acrylic resin, and silicone resin.

5. The broadband optical stealth material for use in exposed surface environments according to claim 4, characterized in that, The crosslinking aid is one or more of the following: isophorone diamine, maleic anhydride, methyltetrahydrophthalic anhydride, triethylenetetramine, benzoyl peroxide, di-tert-butyl peroxide, cyclohexanone peroxide, polyether polyol, polyester polyol, cobalt naphthenate, 3-aminopropylmethoxysilane, and dibutyltin dilaurate.

6. The broadband optical stealth material for use in exposed surface environments according to claim 1, characterized in that, The composite additive includes the following components by weight: 2-7 parts of antifungal agent, 5-10 parts of antiultraviolet agent, and 3-5 parts of antistatic agent.

7. The broadband optical stealth material for use in exposed surface environments according to claim 6, characterized in that, The UV stabilizer is one or more of titanium dioxide, cerium dioxide, phenyl salicylate, bis-2,2,6,6-tetramethylpiperidinol sebacate, and 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole.

8. The broadband optical stealth material for use in exposed surface environments according to claim 6 or 7, characterized in that, The antistatic agent is one or more of tin dioxide, graphene, conductive carbon black, sodium dodecylbenzenesulfonate, and dodecyltrimethylammonium chloride.

9. A method for preparing a broadband optical stealth material for use in exposed surface environments, used to prepare the broadband optical stealth material for use in exposed surface environments as described in any one of claims 1-8, characterized in that, Includes the following steps: The weighed synthetic resin, crosslinking agent, metal oxide pigment and composite additive are mixed evenly to form a premix; The premixed material is heated and cured to obtain the broadband optical stealth material.

10. The method for preparing a broadband optical stealth material for use in exposed surface environments according to claim 9, characterized in that, The heating and curing temperature is 50~100℃, and the heating time is 20~500 min.

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