A multi-band compatible radar stealth multifunctional camouflage net and its preparation method

Abstract

The present invention discloses a multi-band - radar stealth compatible multifunctional camouflage net and a preparation method thereof. The multifunctional camouflage net is a double-layer structure system, which sequentially includes a visible light - infrared composite stealth outer net and a knitted double-sided electromagnetic shielding fabric from top to bottom. The visible light - infrared composite stealth outer net uses high-strength flame-retardant polyester as the base material, and is coated with a visible light - infrared composite stealth coating by means of screen printing technology or coating technology to prepare a composite stealth coating fabric with multi-band camouflage and stealth functions. After the fabric is processed by processes such as cutting and tying, it is mechanically stitched and edged with the knitted double-sided electromagnetic shielding fabric to achieve the function of compatible multi-band camouflage - complete electromagnetic wave shielding. The multi-band - radar stealth compatible multifunctional camouflage net of the present invention is used for the camouflage and stealth of weapon devices, can effectively counter modern high-tech reconnaissance means, and has broad development prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of camouflage and stealth technology, and particularly relates to a multi-band compatible - radar stealth multifunctional camouflage net and a preparation method thereof. Background Art

[0002] In modern warfare, radar detection technology occupies a dominant position among various detectors and plays a crucial role. With the development of infrared detection technology and the advent of advanced infrared detectors, it has also been increasingly applied in reconnaissance, tracking, and guidance technologies, posing an ever-growing threat to military facilities and weaponry.

[0003] With the all-round, multi-level, multi-spectrum, and multi-means development of detection technologies, the single camouflage and stealth performance of camouflage nets can no longer meet the requirements of modern warfare. Current camouflage nets need to be applicable to different backgrounds and have stealth functions in multiple spectral bands.

[0004] Traditional visible light - infrared - radar stealth mostly adopts a layered coating method, that is, first coating one or several layers of radar absorbing coatings on the protected target, and then coating visible light - infrared stealth coatings. Traditional composite stealth coatings generally do not have the effects of segmentation and deformation, and cannot cope with different terrains and changing combat conditions. Facing the complex battlefield survival environment, it is difficult to meet the practical requirements.

[0005] The multi-band compatible - radar stealth multifunctional camouflage net of the present invention is, from top to bottom, a visible light - infrared composite stealth coating fabric and a knitted double-sided electromagnetic shielding fabric. Infrared stealth adopts high, medium, and low emissivities, and the difference between any two is greater than 0.1 to achieve infrared deformation and thermal camouflage segmentation. The surface of the radar stealth uses an absorption-type multi-ion coating, the back uses a fabric blended with metal wires or coated with silver or nickel, and the bottom layer uses a knitted double-sided electromagnetic shielding material, supplemented with different cut flower shapes. When radar waves hit the surface of the camouflage net, first, the absorption-type coating on the surface layer will absorb part of the radar wave energy, and the radar waves penetrating to the bottom layer are reflected by the electromagnetic shielding fabric to the surface radar coating, where they are consumed again, achieving the effect of multiple attenuation and realizing the multi-band - radar compatibility effect.

[0006] The content of the invention The object of the present invention is to provide a multi-band compatible - radar stealth multifunctional camouflage net and a preparation method thereof. The multifunctional camouflage net of the present invention not only has the camouflage and stealth functions in the visible light and infrared bands, but also has a wide-band radar camouflage function. Its preparation method is simple, with low cost and simple process control. The camouflage net can be widely applied to the fields of military equipment and military facilities.

[0007]

[0008] ​The technical solution of the present invention is a multi-band-radar stealth compatible multifunctional camouflage net, which includes a double-layer structure: the outer layer is a visible light-infrared composite stealth outer net, and the inner layer is an electromagnetic shielding fabric; the electromagnetic shielding fabric is a double-sided knitted fabric, and the side close to the visible light-infrared composite stealth outer net is a multi-ion coating fabric for electromagnetic wave absorption; the side far from the visible light-infrared composite stealth outer net is a fiber fabric containing or plated with metal for electromagnetic wave reflection; the visible light-infrared composite stealth outer net and the inner double-sided knitted electromagnetic shielding fabric are sewn and hemmed by mechanical stitching to achieve connection.

[0009] Further, the above-mentioned visible light-infrared composite stealth outer net is obtained by cutting and tying the visible light-infrared composite stealth coating fabric; the visible light-infrared composite stealth coating fabric includes a substrate and a visible light-infrared composite stealth coating applied on the surface of the substrate.

[0010] Further, the substrate of the above-mentioned visible light-infrared composite stealth coating fabric is a flame-retardant polyester fabric with a fineness of 210D; the visible light-infrared composite stealth coating includes a film-forming substance, a low-brightness and low-emissivity pigment filler, a coloring pigment, a solvent, and an additive.

[0011] Further, the composition of the above-mentioned visible light-infrared composite stealth coating is as follows by weight percentage: film-forming substance 30% - 40%; low-brightness and low-emissivity pigment filler 25% - 35%; coloring pigment 5% - 10%; additive 0.2% - 1.0%; solvent 25% - 45%.

[0012] Further, the above-mentioned film-forming substance includes one or more of ethylene propylene diene monomer (EPDM) resin, butyl rubber, cyclized rubber, and polyurethane resin; the solvent includes one or more of toluene, xylene, cyclohexane, absolute ethanol, and tetrahydrofuran; the low-brightness and low-emissivity pigment filler is flake-coated aluminum powder and matte copper powder, and the mass ratio of flake-coated aluminum powder to matte copper powder is (6:1) - (3:1), wherein the flake-coated aluminum powder is one or more of aluminum powder coated with medium chrome yellow, aluminum powder coated with phthalocyanine blue, aluminum powder coated with carbon black, and aluminum powder coated with iron oxide red, and the particle size of the flake-coated aluminum powder is 10 - 25 μm; the coloring pigment is selected from one or more of medium chrome yellow, iron yellow, cobalt blue, chrome green, iron red, and acetylene black; the additive is one or several of ultraviolet aging additives, defoamers, dispersants, and leveling agents.

[0013] Regarding the coloring pigments, the yellow pigment can be selected from titanium yellow, iron yellow, and medium chrome yellow; the blue pigment can be selected from cobalt blue and coated ultramarine; the green pigment can be selected from coated chrome green and cobalt green; the red pigment can be selected from molybdate red and iron red; the black pigment is acetylene carbon black. While meeting the color spectrum regulation, the above pigments can also ensure the weather resistance of the current coating; the coated aluminum powder used in the present invention selects the product developed by the inventor previously. For the product characteristics and process details, see CN113388272A.

[0014] The visible light-infrared composite stealth coating can be prepared into coatings of different colors according to the color matching principle, such as sandy color, brown soil color, medium green, dark green, yellowish green, etc.

[0015] Furthermore, the base material of the above electromagnetic shielding fabric is nylon cloth with a fineness of 75D; the fiber fabric containing metal wires is a stainless steel fiber blended fabric or a silver-nickel-copper fiber blended fabric; the fiber fabric plated with metal is a silver-plated fiber fabric.

[0016] Furthermore, the multi-ion coating fabric in the above electromagnetic wave absorption type multi-ion coating fabric is one of a carbonyl iron powder multi-ion coating fabric, a conductive carbon black multi-ion coating fabric, and a graphene multi-ion coating fabric.

[0017] The present invention also provides a preparation method of the above compatible multi-band-radar stealth multi-functional camouflage net. The visible light-infrared composite stealth outer net and the electromagnetic shielding fabric are stitched and edge-sealed to obtain the compatible multi-band-radar stealth multi-functional camouflage net.

[0018] The method of the present invention specifically includes the following steps:

[0019] (1) Dissolve the film-forming substance in a solvent, then add low-brightness and low-emissivity pigment fillers, coloring pigments, and additives, and perform high-speed grinding and dispersion to obtain a visible light-infrared composite stealth coating.

[0020] (2) Fix the base material of the visible light-infrared composite stealth coating fabric on a coating machine, and coat it with the coating in step (1) to form a visible light-infrared composite stealth coating film. The thickness of the stealth coating film is 10 - 15 μm, and then it is dried in a constant temperature dry environment at 100 - 120 °C to obtain a visible light-infrared composite stealth coating fabric.

[0021] (3) Perform cutting and tying process treatments on the dried visible light-infrared composite stealth coating fabric.

[0022] (4) Stitch and edge-seal the visible light-infrared composite stealth coating fabric after the cutting and tying process treatments with the electromagnetic shielding fabric to obtain the compatible multi-band-radar stealth multi-functional camouflage net.

[0023] Further, step (1) specifically includes: accurately weighing the film-forming substance and the solvent according to a ratio, mixing them and placing them in a high-speed disperser, and then sequentially adding the low-brightness and low-emissivity pigment fillers, coloring pigments, and additives thereto, and dispersing for 30 min to 60 min at a rotation speed of 1500 r / min to 2500 r / min; then transferring the uniformly dispersed mixture to a ball mill, adding zirconium beads of different diameters for ball milling until the fineness reaches ≤25 μm, and filtering to obtain the visible-infrared composite stealth coating; in the said step (2), the substrate of the visible-infrared composite stealth coating fabric is scrubbed with absolute ethanol before use and dried at 50 to 60 °C; in the said step (4), overlock sewing is adopted for sewing and hemming, using polyester carbon fiber fine thread or silver-plated fine thread as the sewing thread, with a linear density of 9 to 12 stitches / 3 cm and a sewing machine needle number of 8 to 10.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention explores from two aspects of the structure of the camouflage net and the multifunctional stealth coating, and adopts the method of combining the multifunctional stealth camouflage coating technology with the double-layer electromagnetic shielding fabric to achieve the purpose of multi-spectrum-radar stealth compatibility: The fabric used for the visible-infrared composite stealth outer net of the present invention is coated with a coating including low-brightness and low-emissivity pigment fillers, which is formulated by combining aluminum powder, film-forming substance, coloring pigments, etc. After being coated with aluminum powder, it not only exhibits the characteristics of the coloring pigment, but also allows the aluminum powder to be distributed in the coating in the form of flakes, meeting the requirement of reducing the infrared emissivity, and solving the problems that in traditional aluminum powder pigments for dark camouflage coatings, the lightness L value of the coating cannot be reduced and it cannot be used in medium-emissivity or low-emissivity camouflage coatings, etc., realizing the compatibility of optical and infrared stealth; for the double-layer camouflage net structure of the present invention, the radar stealth surface adopts an absorption-type multi-ion coating, the back adopts a fabric blended with metal wire or silver-plated or nickel-plated, and the bottom layer adopts a knitted double-sided electromagnetic shielding material, supplemented with different cut flower shapes. When the radar wave hits the surface of the camouflage net, first, a part of the radar wave energy will be absorbed by the absorption-type coating on the surface layer, and the radar wave penetrating to the bottom layer will be reflected by the electromagnetic shielding fabric to the surface radar coating and be consumed again, achieving the effect of multiple attenuation and realizing the effect of multi-band-radar compatibility.

[0026] 2. The multifunctional camouflage net of the present invention has good anti-detection performance in the visible light, infrared, and radar bands, can effectively counter modern high-tech reconnaissance means and facilities, and can be used as a new type of multi-band camouflage barrier material in the camouflage net, having outstanding advantages such as low price and convenient use.

[0027] The camouflage net with the function of compatible multi-band - radar stealth has the advantages of simple preparation, low cost, convenient use, and can meet different complex battlefield environments. It has good camouflage and stealth functions in the visible light, infrared, and radar bands, and can be widely used as a camouflage barrier equipment in the fields of military vehicles, military equipment, radar bases, missile launch devices and other military facilities. Brief Description of the Drawings

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0029] Figure 1 It is the desert-type multi-band - radar stealth multifunctional camouflage net in the embodiment of the present invention.

[0030] Figure 2 For Figure 1 the infrared test performance diagram of the shown desert-type multi-band - radar stealth multifunctional camouflage net.

[0031] Figure 3 It is the woodland-type multi-band - radar stealth multifunctional camouflage net in the embodiment of the present invention.

[0032] Figure 4 For Figure 3 the infrared test performance diagram of the shown woodland-type multi-band - radar stealth multifunctional camouflage net. Detailed Embodiments

[0033] To make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below. The fabrics and reagents used are all conventional products obtained by purchasing on the market.

[0034] The obtained desert-type multi-band - radar stealth multifunctional camouflage net is as Figure 1 shown.

[0035] The preparation and application of the compatible multi-band - radar stealth multifunctional camouflage net of the present invention will be specifically described below through embodiments.

[0036] Example 1

[0037] A fabric with a medium green MG1151 visible light - infrared composite stealth coating, and its preparation specifically includes the following steps:

[0038] Scrub the preferred high-strength flame-retardant polyester fabric substrate with absolute ethanol to remove impurities such as residual dust, flame retardant, and polyester fibers on the surface, and then dry it in an electrothermal constant-temperature dryer at 50 °C for standby.

[0039] Accurately weigh ethylene propylene diene monomer (EPDM) resin and polyurethane resin according to a mass ratio of 4:1, dissolve them in xylene solvent, heat to 60 °C and stir to accelerate dissolution, then add matte copper powder and low-brightness coated aluminum powder, and add appropriate amounts of preferred coloring pigments and additives according to the color matching principle to prepare medium green MG1151 camouflage coating. The specific mass fractions of each component are as follows:

[0040] EPDM resin / polyurethane mixed resin: 40;

[0041] Matte copper powder: 5;

[0042] Phthalocyanine blue coated aluminum powder: 15;

[0043] Carbon black coated aluminum powder: 10;

[0044] Iron oxide red coated aluminum powder: 5;

[0045] Chrome green: 3.4;

[0046] Medium chrome yellow: 2.8;

[0047] Acetylene carbon black: 0.4;

[0048] Iron red: 0.6;

[0049] Xylene organic solvent: 25;

[0050] Other additives: 0.8 (ultraviolet absorber: 0.2, dispersant: 0.3, leveling agent: 0.2, defoaming agent: 0.1).

[0051] According to the above formula, add each component substance in turn and carry out high-speed stirring and dispersion. After the coating is prepared, apply the above visible-infrared composite stealth coating on the high-strength flame-retardant polyester fabric substrate by screen printing, and then dry the coated fabric in a drying oven at 100 °C.

[0052] Example 2

[0053] A fabric with a loess color YE1529 visible-infrared composite stealth coating, and its preparation specifically includes the following steps:

[0054] Scrub the preferred high-strength flame-retardant polyester fabric substrate with absolute ethanol to remove impurities such as residual dust, flame retardant, and polyester fibers on the surface, and then dry it in an electrothermal constant-temperature drying oven at 60 °C for standby.

[0055] Accurately weigh ethylene propylene diene monomer (EPDM) resin and dissolve it in xylene solvent. Heat it to 60 °C and stir to accelerate dissolution. Then add matte copper powder and low-luminance coated aluminum powder. Add appropriate amounts of selected coloring pigments and additives according to the color matching principle to prepare the loess YE1529 camouflage coating. The specific mass fractions of the components are as follows:

[0056] Ethylene propylene diene monomer (EPDM) resin: 36;

[0057] Matte copper powder: 5;

[0058] Medium chrome yellow coated aluminum powder: 15;

[0059] Iron oxide red coated aluminum powder: 5;

[0060] Chrome green: 0.4;

[0061] Medium chrome yellow: 4.3;

[0062] Acetylene carbon black: 0.2;

[0063] Iron red: 1.3;

[0064] Xylene organic solvent: 45;

[0065] Other additives: 0.8 (ultraviolet absorber: 0.3, dispersant: 0.3, leveling agent: 0.2).

[0066] According to the above formula, add each component substance in sequence and carry out high-speed stirring and dispersion. After the coating is prepared, the above visible light-infrared composite stealth coating will be coated on the 210D high-strength flame-retardant polyester fabric substrate by coating technology, and then the coated fabric will be dried in a drying oven at 100 °C.

[0067] Example 3

[0068] According to the methods of Examples 1-2, through color matching and substrate design, obtain visible light-infrared composite stealth coating fabrics of the other four colors required for desert-type camouflage nets and woodland-type camouflage nets;

[0069] According to the color distribution of typical ground object backgrounds, splice, cut and tie the visible light-infrared composite stealth coating fabrics to obtain desert-type camouflage nets as Figure 1 shown, and woodland-type camouflage nets as Figure 3 shown.

[0070] The knitted double-sided electromagnetic shielding fabric matching the desert-type camouflage net preferably uses a reflection-absorption type knitted fabric, which is a blended fabric of stainless steel fibers / carbon black conductive multi-ion coating fabric. The desert-type camouflage net is stitched with the knitted double-sided electromagnetic shielding fabric of stainless steel fiber blend / copper-nickel metal fiber. Silver-plated fine wire is used as the sewing thread, and the two fabrics are stitched in an overlock sewing method. The stitch density is 9 stitches / 3 cm and the sewing machine needle number is 8. The above two fabrics are mechanically sewn and edge-treated to obtain a desert-type compatible multi-band-radar stealth camouflage net.

[0071] The knitted double-sided electromagnetic shielding fabric matching the woodland-type camouflage net preferably uses a reflection-absorption type knitted double-sided fabric, which is a silver-plated fiber / graphene multi-ion coating fabric. The woodland-type camouflage net is stitched with the knitted double-sided electromagnetic shielding fabric of silver-plated fiber / copper-nickel metal fiber. Silver-plated fine wire is used as the sewing thread, and the two fabrics are stitched in an overlock sewing method. The stitch density is 10 stitches / 3 cm and the sewing machine needle number is 9. The above two fabrics are mechanically sewn and edge-treated to obtain a woodland-type compatible multi-band-radar stealth camouflage net.

[0072] Test Example

[0073] The compatible multi-band-radar stealth camouflage net obtained in Example 3 above is made into a sample net of 200 mm×180 mm. The test standards for electromagnetic shielding effectiveness are GB 12190–2006 "Measurement Methods for Electromagnetic Shielding Effectiveness of Electromagnetic Shielding Rooms" and QJ2809–1996 "Measurement Methods for Shielding Effectiveness of Flat Materials"; the infrared emissivity test is carried out by using the IR-2 dual-band emissivity tester developed by the Shanghai Institute of Technical Physics, Chinese Academy of Sciences to measure the infrared emissivity of the coating in the 3-5 μm and 8-14 μm bands. The infrared test performances of the desert-type compatible multi-band-radar stealth camouflage net and the woodland-type compatible multi-band-radar stealth camouflage net products are respectively as Figure 2 and Figure 4 shown, and the results are shown in Table 1.

[0074] Table 1: Test Results of Two Different Color Compatible Multi-band-Radar Stealth Camouflage Nets

[0075]

[0076] The embodiments described above are some embodiments of the present invention, not all embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts fall within the scope of protection of the present invention.

Claims

1. A preparation method of a multi-band-radar stealth multifunctional camouflage net, characterized in that Sew and hem the outer visible light-infrared composite stealth outer net and the inner electromagnetic shielding fabric to obtain the multi-band-radar stealth compatible multi-functional camouflage net; the method includes the following steps: (1) Dissolve the film-forming substance in a solvent, then add low-brightness and low-emissivity pigments, coloring pigments and additives, and perform high-speed grinding and dispersion to obtain a visible light-infrared composite stealth coating; (2) Fix the substrate of the visible light-infrared composite stealth coating fabric on a coating machine, and coat with the coating in step (1) to form a visible light-infrared composite stealth coating film with a thickness of 10-15 μm, and then dry it in a constant temperature dry environment at 100-120 °C to obtain a visible light-infrared composite stealth coating fabric; (3) Perform flower cutting and lashing process on the dried visible light-infrared composite stealth coating fabric; (4) Sew and hem the visible light-infrared composite stealth coating fabric after the flower cutting and lashing process with the electromagnetic shielding fabric to obtain the multi-band-radar stealth compatible multi-functional camouflage net; The specific steps of step (1) include: accurately weighing the film-forming substance and the solvent in proportion and placing them in a high-speed disperser, and then sequentially adding the low-brightness and low-emissivity pigments, coloring pigments, and additives to the high-speed disperser, and dispersing at a rotation speed of 1500 r / min to 2500 r / min for 30 min to 60 min; then transfer the uniformly dispersed mixture to a ball mill, add zirconium beads of different diameters for ball milling, grind to a fineness of ≤25 μm, and filter to obtain a visible light-infrared composite stealth coating; In step (2), the substrate of the visible light-infrared composite stealth coating fabric is scrubbed with anhydrous ethanol before use and dried at 50-60 °C; In step (4), the sewing and hemming are carried out in an overlock sewing method, using polyester carbon fiber fine thread or silver-plated fine thread as the sewing thread, with a linear density of 9-12 stitches / 3 cm and a sewing needle number of 8-10; 2. A multi-band-radar stealth compatible multifunctional camouflage net prepared by the preparation method according to claim 1, characterized in that, It includes a double-layer structure: the outer layer is a visible light-infrared composite stealth outer net, and the inner layer is an electromagnetic shielding fabric; The electromagnetic shielding fabric is a knitted double-sided fabric, with a side close to the visible light-infrared composite stealth outer net being an electromagnetic wave absorption type multi-ion coating fabric; and a side far from the visible light-infrared composite stealth outer net being an electromagnetic wave reflection type metal-containing or metal-plated fiber fabric; The visible light-infrared composite stealth outer net and the inner knitted double-sided electromagnetic shielding fabric are sewn and hemmed by mechanical sewing to achieve connection.

3. The multi-band-radar stealth compatible multifunctional camouflage net according to claim 2, characterized in that, The visible light-infrared composite stealth outer net is obtained by flower cutting and lashing the visible light-infrared composite stealth coating fabric; the visible light-infrared composite stealth coating fabric includes a substrate and a visible light-infrared composite stealth coating applied to the surface of the substrate.

4. The multi-band-radar stealth compatible multi-functional camouflage net according to claim 3, wherein the substrate of the visible light-infrared composite stealth coating fabric is a flame-retardant polyester fabric with a fineness of 210 D; The visible light-infrared composite stealth coating comprises a film-forming substance, low-brightness and low-emissivity pigments and fillers, coloring pigments, a solvent and additives.

5. The multi-band-radar stealth compatible multifunctional camouflage net according to claim 4, characterized in that, The composition of the visible light-infrared composite stealth coating is as follows by weight percentage: The film-forming substance: 30% - 40%; The low-brightness and low-emissivity pigments and fillers: 25% - 35%; The coloring pigments: 5% - 10%; The additives: 0.2% - 1.0%; The solvent: 25% - 45%.

6. The multi-band-radar stealth compatible multifunctional camouflage net according to claim 5, characterized in that The film-forming substance includes one or more of ethylene propylene diene monomer (EPDM) resin, butyl rubber, cyclized rubber, polyurethane resin; The solvent includes one or more of toluene, xylene, cyclohexane, absolute ethanol, tetrahydrofuran; The low-brightness and low-emissivity pigments and fillers are flaky coated aluminum powder and matte copper powder, and the mass ratio of the flaky coated aluminum powder to the matte copper powder is (6:1) - (3:1), wherein the flaky coated aluminum powder is one or more of aluminum powder coated with medium chrome yellow, aluminum powder coated with phthalocyanine blue, aluminum powder coated with carbon black, aluminum powder coated with iron oxide red, and the particle size of the flaky coated aluminum powder is 10 - 25 μm; The coloring pigments are selected from one or more of medium chrome yellow, iron yellow, cobalt blue, chrome green, iron red, acetylene carbon black; The additives are one or several of ultraviolet aging additives, defoamers, dispersants, leveling agents.

7. The multi-band-radar stealth compatible multifunctional camouflage net according to claim 2, characterized in that, The substrate of the electromagnetic shielding fabric is nylon cloth with a fineness of 75D; the fiber fabric containing metal wires is a stainless steel fiber blended fabric or a silver-nickel-copper fiber blended fabric; the metal-coated fiber fabric is a silver-coated fiber fabric.

8. The multi-band-radar stealth compatible multifunctional camouflage net according to claim 2, characterized in that, The multi-ion coating fabric in the electromagnetic wave absorption type multi-ion coating fabric is one of a carbonyl iron powder multi-ion coating fabric, a conductive carbon black multi-ion coating fabric, and a graphene multi-ion coating fabric.

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