The present invention relates generally to multi-layer fabrics, and particularly to layered fabrics having multi-spectral camouflage capabilities.
Traditionally, camouflage fabrics have been colored and textured so as to make it difficult to visually distinguish the fabric from its surroundings. With the increasing importance of thermal and radar imaging in the battlefield, some camouflage fabrics are now designed to suppress infrared and/or microwave radiation, as well.
For example, U.S. Patent Application Publication 2010/0112316, whose disclosure is incorporated herein by reference, describes a visual camouflage system that includes a vinyl layer having a camouflage pattern on its front surface with a site-specific camouflage pattern. A laminate layer is secured over the front surface of the vinyl layer, coating the camouflage pattern to provide protection to the camouflage pattern and strengthen the vinyl layer. One or more nanomaterials are disposed on the vinyl layer, the camouflage pattern, or the laminate to provide thermal and/or radar suppression.
As another example, U.S. Pat. No. 7,148,161, whose disclosure is incorporated herein by reference, describes a thermal camouflage tarpaulin for hiding heat sources against detection in a thermal image. The tarpaulin comprises a base textile composed of a knitted or woven glass fabric on the side that is remote from the heat source with a compound whose reflectance values are in the region of a visual camouflage and/or in the infrared region. The base textile is provided with a free-standing polyester film to which a vapor-deposited coating that reflects thermal radiation has been applied on the side facing the heat source.
As a further example, U.S. Pat. No. 7,244,684, whose disclosure is incorporated herein by reference, describes a thermal camouflage sheet for covering heat sources against identification in a thermal image. The sheet has a base textile with a glass filament, with a coating that contains aluminum powder on one side and a coating that contains color pigments on the other side. The remission values of the color pigments are in a range that allows camouflaging in the visual-optical and near infrared.
Embodiments of the present invention that are described hereinbelow provide multispectral, multi-purpose camouflage materials that can be used in a wide range of different ambient conditions.
There is therefore provided, in accordance with an embodiment of the present invention, a fabric, including a first flexible fabric layer, having fabric emissivity properties in a visible radiation range that are selected so as to mimic ambient emissivity properties of a deployment environment of the fabric. At least one second flexible fabric layer is joined to the first flexible fabric layer, and is configured to scatter long-wave radiation that is incident on the fabric. The first and second flexible fabric layers are perforated by a non-uniform pattern of perforations extending over at least a part of the fabric.
Typically, the long-wave radiation scattered by the at least one second flexible fabric layer includes infrared thermal radiation and/or microwave radiation.
The perforations may have multiple different sizes and shapes, such as triangular or quadrilateral forms.
In disclosed embodiments, the at least one second flexible fabric layer includes microballoons, a metallic film, and/or a conductive net.
There is also provided, in accordance with an embodiment of the present invention, a camouflage garment, including a fabric as described above, wherein the fabric is cut and sewn so as to be worn over the body of an ambulatory human subject.
The fabric may be cut and sewn so as to provide a first configuration that camouflages the subject in a first deployment environment and, when the garment is turned inside-out, a second configuration that camouflages the subject in a second deployment environment.
There is additionally provided, in accordance with an embodiment of the present invention, a method for producing a fabric, which includes providing a first flexible fabric layer, having fabric emissivity properties in a visible radiation range that are selected so as to mimic ambient emissivity properties of a deployment environment of the fabric. At least one second flexible fabric layer, which is configured to scatter long-wave radiation that is incident on the fabric, is joined to the first flexible fabric layer. The first and second flexible fabric layers are perforated with a non-uniform pattern of perforations extending over at least a part of the fabric.
There is further provided, in accordance with an embodiment of the present invention, a camouflage garment, including a fabric that is cut and sewn so as to be worn over the body of an ambulatory human subject, wherein the fabric has a first configuration that camouflages the subject in a first deployment environment and, when the garment is turned inside-out, a second configuration that camouflages the subject in a second deployment environment, different from the first deployment environment.
In one embodiment, the first deployment environment is a daytime environment, and the second deployment environment is a nighttime environment. Additionally or alternatively, the first deployment environment is a vegetated environment, and the second deployment environment is a desert environment.
In a disclosed embodiment, the garment includes quick-connect fasteners between a torso and extremity sleeves of the garment, wherein the fasteners are configured to permit the extremity sleeves to be fastened to the torso while one or more of the extremity sleeves are turned inside-out relative to the torso.
The present invention will be more fully understood from the following detailed description of the embodiments thereof, taken together with the drawings in which:
Camouflage fabrics are commonly used in producing military uniforms that reduce the daytime visibility of the wearer, but wearable camouflage against detection by long-wave sensors (thermal infrared or microwave radar) has yet to be widely deployed. Thermal and radar camouflage materials that are known in the art tend to be too heavy for use by ambulatory foot soldiers and do not allow sufficient ventilation or heat exchange to maintain a reasonable level of comfort. They are thus not practical for operational use.
Embodiments of the present invention that are described hereinbelow address these problems by providing a multilayer fabric that is sufficiently light and ventilated to be used in camouflage suits for ambulatory human subjects. The fabric is also suitable, however, for covering animals, vehicles, boats, aircraft and stationary objects. The fabric comprises one fabric layer having emissivity properties in the visible radiation range that are selected so as to mimic ambient emissivity properties of the deployment environment of the fabric, thus providing visual camouflage. One or more additional flexible fabric layers, joined to the visual camouflage layer, are configured to scatter long-wave radiation that is incident on the fabric and thus provide infrared and/or microwave camouflage.
The fabric layers are perforated by a non-uniform pattern of perforations extending over part or all of the fabric. These perforations typically have multiple different sizes and shapes, such as different triangular or quadrilateral forms. The inventors have found that such non-uniform perforations serve multiple purposes: They both provide ventilation to the inside of the fabric and reduce its weight, and they also blur the long-wave radiation returned by the fabric to thermal and radar imaging devices. These features are valuable in substantially all camouflage applications, but they are particularly useful when the fabric is cut and sewn to be worn over the human body as a camouflage garment, such as a full-body camouflage suit.
Alternatively or additionally, the two outer fabric layers may be configured to camouflage the wearer in different physical deployment environments. For example, one side may be designed to provide camouflage in a vegetated environment (such as a forest), while the other side provides camouflage in desert environments, in which vegetation is sparse or absent entirely.
For visual, daytime camouflage, fabric 30 comprises an outer layer 32 of ripstop cotton, with a suitable pattern (such as that shown in
An underlying layer 34 containing glass microballoons is laminated to layer 32 using a spun web 40 of polyurethane fibers. The microballoons, whose sizes are in the range of 50-500 μm, scatter radiation, particularly infrared radiation, and thereby blurs the thermal signature of the wearer. Alternatively or additionally, some or all of the microballoons may be coated with metal to improve their microwave-scattering properties and thereby blur the radar signature of the wearer. Although microballoons are typically round, some or all of the microballoons in layer 34 may be prismatic in shape. In alternative embodiments, microballoons may be located between other layers of the fabric or may be coated over the outer fabric surface.
A reflective layer 36 may be fixed to the underside of layer 34, to provide specular scattering of infrared and/or microwave radiation. Layer 36 may comprise, for example, a polyester weave coated with a metallic film, such as titanium and/or aluminum or aluminum mixed with titanium oxide, gold, nickel and their alloys and/or oxides. The weave may alternatively be made using fibers containing suitable metals, in which case an additional layer of reflective lamination is not needed. The polyester may conveniently be a ripstop, water-repellant material.
For nighttime camouflage, an alternative outer layer 38 may be printed with a suitable pattern (also in low-emissivity pigment) and laminated to layer 36 by another polyurethane spun web 42. Layer 38, may comprise, for example, a 40-denier ripstop nylon, which is water-repellant and air-permeable, produced and coated using a suitable nano-process, which gives superior results to conventional water-repellant treatments using larger particles.
Multiple perforations 44 are cut through the layers of fabric 30. Typically, the perforations are in the range of 2-3 mm wide and are spaced 7-25 mm apart. The perforations may be of different shapes and sizes, as illustrated, for example, in
The overall thickness of fabric 30, based on the above sequence of layers, is approximately 0.20-0.40 mm and the weight is roughly 150-250 grams/m2. A suit made from this fabric, of the sort shown in
A variety of other layer structures can be used in alternative embodiments of the present invention. Table 1 below lists typical materials that can be used in these structures, while Tables A-J show examples of layer structures that can be composed from these materials.
The above embodiments are shown here only by way of example, and alternative layer structures, which will be apparent to those skilled in the art upon reading this specification, are also considered to be within the scope of the present invention.
As noted earlier, perforations 44 are useful in providing ventilation, to prevent overheating inside suit 20, and the non-uniformity of the perforations helps to blur the thermal and/or radar signature of the wearer. For good ventilation in warm weather conditions, the perforations may be supplemented by vents in the sewn fabric. Typically, an air flow rate of 1-3 cubic feet per minute (CFM) at a pressure of 20-30 pascal is desirable.
In addition, suit 50 comprises quick-connect fasteners 58 between a torso 52 and arms 54 and legs 56 of the garment. (The arms and legs of the garment are collectively referred to as “extremity sleeves” in the present description and in the claims.) Quick-connect fasteners 58 may comprise zippers, for example, or any other suitable type of connecting element that permits the extremity sleeves to be attached to and detached from torso 52 without the need to sew or open stitches or otherwise permanently modify the fabric. Fasteners 58 permit arms 54 and legs 56 to be fastened to torso 52 either with the same fabric layer facing outward or turned inside-out relative to the torso. Thus, in the example shown in
It will be appreciated that the embodiments described above are cited by way of example, and that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art.
Number | Date | Country | Kind |
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215717 | Oct 2011 | IL | national |
This application is a continuation of U.S. patent application Ser. No. 16/230,174, filed on Dec. 21, 2018, which is a continuation of U.S. patent application Ser. No. 14/350,084, filed on Apr. 7, 2014, issued U.S. Pat. No. 10,203,183 on Feb. 12, 2019, which claims priority to PCT/IB12/52142 filed on Apr. 29, 2012, which claims priority to Israeli Patent Application No. 215717, filed on Oct. 11, 2011, the contents of which are incorporated by reference herein in their entirety.
Number | Name | Date | Kind |
---|---|---|---|
2911652 | Ekman | Nov 1959 | A |
3315259 | Wesch | Apr 1967 | A |
3733606 | Johansson | May 1973 | A |
4287243 | Nielsen | Sep 1981 | A |
4308882 | Pusch et al. | Jan 1982 | A |
4473826 | Pusch et al. | Sep 1984 | A |
4479994 | Berg | Oct 1984 | A |
4493863 | Karlsson | Jan 1985 | A |
4529633 | Karlsson | Jul 1985 | A |
4645704 | Hellwig | Feb 1987 | A |
5348789 | Hellwig | Sep 1994 | A |
6047404 | Blanks | Apr 2000 | A |
6179367 | Bowen | Jan 2001 | B1 |
7148161 | Hellwig et al. | Dec 2006 | B2 |
7244684 | Hexels | Jul 2007 | B2 |
7832018 | Schwarz | Nov 2010 | B2 |
8013776 | Child | Sep 2011 | B2 |
9163907 | Schwarz | Oct 2015 | B2 |
9952020 | Schwarz | Apr 2018 | B2 |
10203183 | Morag | Feb 2019 | B2 |
10960654 | Morag | Mar 2021 | B2 |
20010001753 | Nelson et al. | May 2001 | A1 |
20070148449 | Winterhalter | Jun 2007 | A1 |
20090081453 | Edman et al. | Mar 2009 | A1 |
20090263644 | Kelsey et al. | Oct 2009 | A1 |
20100093238 | Schwarz | Apr 2010 | A1 |
20100112316 | Cincotti et al. | May 2010 | A1 |
20100288116 | Cincotti et al. | Nov 2010 | A1 |
20140304883 | Morag et al. | Oct 2014 | A1 |
20180037034 | Ohnishi | Feb 2018 | A1 |
Number | Date | Country |
---|---|---|
0490467 | Jun 1992 | EP |
1703247 | Sep 2006 | EP |
2101876 | Jan 1983 | GB |
202410 | Nov 2010 | IL |
167330 | Jan 2011 | IL |
2010134080 | Nov 2010 | WO |
Entry |
---|
Textile Value Chain, Making of Camouflage, and it's Applications, accessed online Sep. 10, 2023. |
Apr. 29, 2013—International Search Report PCT/IB2012/052142. |
Mar. 2, 2018 (AU) Australian Examination Report—App 2017203449. |
Mallinckrodt Baker, Inc., “Aluminum Powder—MSDS No. A2712”, 11 pages, Dec. 8, 1996. |
New World Textile Testing Laboratory, “Product: 70 Denier—Nylon Multicam DWR Finished (Non-Coated)”, 2 pages, Oct. 22, 2010. |
3M™, “3M™ Screen Printable UV-Curing Adhesive 7555”, 4 pages, 2008. |
Yail Noa Group, “Fabric: Epsilon Multicam”, Technical Data Sheet, 1 page, Aug. 28, 2011. |
Diatex, M3526 PA/CO, Fiche technique Technical data sheet/Specification, 1 page, Oct. 2006. |
Soliani EMC SRL, “Electrically Conductive Fabric Ponge”, Technical data sheet, Rev. 2, 1 page, Jun. 18, 2009. |
Shing Fu Fiber Dyeing & Finishing Co., Ltd., “Featured Products”, 2 pages, year 2009. |
Freudenberg, “Vilene Products—Nonwoven Classic Interlinings”, 1 page, year 2015. |
European Application# 12840209.6 Search Report dated Apr. 14, 2015. |
Number | Date | Country | |
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20210197542 A1 | Jul 2021 | US |
Number | Date | Country | |
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Parent | 16230174 | Dec 2018 | US |
Child | 17201758 | US | |
Parent | 14350084 | US | |
Child | 16230174 | US |