Patent Application
20140154482
This application claims the benefit of Korean Patent Application No. 10-2011-0068211, filed on Jul. 11, 2011 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
The present invention relates to a camouflage fabric with near infrared ray reflectance adjusting characteristics, and more particularly, to a camouflage fabric with near infrared ray reflectance adjusting characteristics, which can solve secession of application chemicals when a near infrared absorbing pigment or a carbon compound is coated on a synthetic fabric in a typical camouflage fabric manufacturing method, by weaving a camouflage fabric having a camouflage performance against a near infrared observation sensor using a conductive yarn containing copper sulfide nanoparticles or metal sulfide nanoparticles including copper sulfide, and has a Near Infrared Ray Reflectance (NIRR) that is identical to or similar to colorful natural backgrounds in the spectral reflectance in a near infrared spectrum in which a near infrared ray wavelength band ranges about 720 nm to about 1,500 nm. Also, since metal sulfide nanoparticles including copper sulfide and copper sulfide nanoparticles have antimicrobial properties and conductive properties, the camouflage fabric, which has superior physiochemical properties and naturally exhibits antimicrobial properties and antistatic properties even without a separate post-treatment, can be provided.
Generally, the probability of military personnel, vehicles, equipment, structures etc., so called ‘targets,’ surviving in the battlefield is directly related to the capability of responsive measure that can minimize all threats thereto.
One of the important responsive measures of the target against the threat thereto is camouflaging, such that it will be difficult for the enemy to detect the existence of such target.
In order for the target to conceal itself from the detection by a near infrared ray observation device at night, clothes must camouflage itself by having an equal or similar level of near infrared ray reflectance to those of surrounding objects, within the near infrared ray wavelength region of 720 nm to 1,500 nm, whereas the effective camouflaging to avoid detection by naked eye or visible ray detection equipment during the day can be achieved by applying a color camouflage that is performed in 380 nm to 720 nm spectrum, i.e., visible ray region.
Accordingly, in order for a camouflage to be equally effective at both day and night, clothes must have the pattern, color, brightness and chroma resembling its surroundings, which will successfully conceal the target by making it difficult to be detected within the area of visible ray during the day, and clothes must have the level of near infrared ray reflectance equal or similar to those of the surroundings, in consideration of the near infrared ray wavelength region used by the near infrared observation device used at night.
The near infrared detection wavelength region of the near infrared observation device used to range from 600 nm to 860 nm, but the recent technical development allows its maximum range to be extend to 1,000 nm to 1,500 nm.
This results from the development of electronic equipment that can detect a wider region than the existing military equipment.
Since there are various environments throughout the world, many different camouflaging materials, including both visible and invisible, are available.
The various environments (for example, from forests to deserts) require the use of various colors and patterns.
For example, the camouflaging materials used by military in the visible ray region and in the forest usually use four colors of black, brown, green and bright green.
On the other hand, the camouflaging materials in the desert, during the day, usually use three colors of brown, khaki and yellowish brown.
The fibers with camouflaging patterns for visible ray environment are typically manufactured by printing the camouflaging patterns on the surface of undyed greige fiber or by solution-dyeing the spun yarn that is successively woven or knitted into the camouflaging patterns by, e.g., a jacquard process.
However, the materials must be processed differently from those in the visible ray region, to avoid the detection by near infrared observation devices during a night combat.
The near infrared camouflage fabric, which means an invisible camouflaging material for the night time, means a fabric that allows a wearer to avoid detection by near infrared night observation device by allowing the fabric to have a near infrared ray reflectance similar to that of its surrounding environment.
This fabric has a very important value in the modern war due to the development of near infrared night observation devices.
A method of manufacturing a typical near infrared camouflage fabric is as follows.
In order to achieve a desired camouflage simultaneously in both the visible ray and near infrared ray, a printing process is performed on a fiber that is not dyed by an existing method or dyed in base color to achieve a level of both near infrared reflectance and color for day and night times.
Most typically, the near infrared reflectance of fiber is changed by adding an adequate amount of carbon black and near infrared ray absorbing pigment to the camouflage print ink and paste.
The limitation of this method is that the carbon black added is so excessively dark that the carbon black may impose a negative effect to the visible tone intended for the camouflage fiber. In an environment such as the desert that requires a considerably bright tone, this method has a limitation in achieving appropriate visible and near infrared ray camouflages.
Particularly, since washing-off and peeling-off can easily occur in spite of local carbon finishing, the fiber treated as such can provide only a low-level durability in terms of concealing performance against the near infrared detection.
Also, the organic pigments among near infrared ray absorbing pigments, such as diimmonium, polymethine, metal complex, squarium type, and cyanine, mainly absorb the wavelength of 800 nm to 1,100 nm, but their near infrared ray absorption performance in the wavelength band equal to or greater than 1,100 nm is significantly reduced and their weatherproof performances of physicochemical characteristics may be significantly reduced because the pigments are seceded when repeatedly washed. On the other hand, the inorganic pigments, such as cobalt, vanadium, molybdenum, tungsten, ITO, ATO, and ruthenium, effectively interrupt and absorb rays mainly in the wavelength equal to or greater than 1,200 nm, but the inorganic pigments are very expensive and also there is still a limitation in weather resistance due to the secession.
The present invention provides a camouflage fabric with near infrared ray reflectance adjusting characteristics, which can significantly improve a poor durability occurring when a near infrared absorbing pigment and a carbon compound are coated on a synthetic fabric in a typical camouflage fabric manufacturing method, by weaving a camouflage fabric having a camouflage performance against a near infrared observation sensor using a conductive yarn containing copper sulfide nanoparticles or metal sulfide nanoparticles including copper sulfide.
The present invention also provides a camouflage fabric with near infrared ray reflectance adjusting characteristics, which can achieve a certain camouflage effect by allowing a Near Infrared Ray Reflectance (NIRR) to be identical to or similar to those of natural backgrounds in a near infrared spectrum in which a near infrared ray wavelength band ranges about 720 nm to about 1,500 nm.
The present invention also provides a camouflage fabric with near infrared ray reflectance adjusting characteristics, which can be used for military clothes, equipment, tents, and instruments by providing a camouflage fabric that has superior physiochemical properties and naturally exhibits antimicrobial properties and antistatic properties even without a separate post-treatment because metal sulfide nanoparticles including copper sulfide and copper sulfide nanoparticles have antimicrobial properties and conductive properties.
In accordance with an aspect of the present invention, there is provided a camouflage fabric with near infrared ray reflectance adjusting characteristics, characterized in that the near infrared ray reflectance of the camouflage fabric is equal or similar to the near infrared ray reflectance of surrounding objects in a near infrared ray spectrum of about 720 nm to about 1,500 nm using a conductive synthetic polymer material in which metal sulfide nanoparticles including copper sulfide or copper sulfide nanoparticles are coordinated-bonded to a polymer matrix.
The present invention can significantly improve a poor durability occurring when a near infrared absorbing pigment and a carbon compound are coated on a synthetic fabric in a typical camouflage fabric manufacturing method, by weaving a camouflage fabric having a camouflage performance against a near infrared observation sensor using a conductive yarn containing copper sulfide nanoparticles or metal sulfide nanoparticles including copper sulfide.
The present invention can more effectively achieve a certain camouflage effect by allowing a Near Infrared Ray Reflectance (NIRR) to be identical to or similar to those of natural backgrounds in a near infrared spectrum in which a near infrared ray wavelength band ranges about 720 nm to about 1,500 nm.
More specifically, two types of multifilament yarns including a first multifilament yarn and a second multifilament yarn are woven into plain weave or fancy plain weave as a warp and a weft by a loom. Since the two types of filament yarns are woven so as to have a specific near infrared ray reflectance of about 25% to about 70% according to a blending ratio of the first multifilament yarn and the second multifilament yarn in a near infrared ray spectrum region of about 720 nm to about 1,500 nm, the camouflage fabric can provide a wearer with an improved concealment against near infrared observation devices in any surrounding environment.
Meanwhile, the present invention can provide a camouflage fabric that has superior physiochemical properties and naturally exhibits antimicrobial properties and antistatic properties even without a separate post-treatment because metal sulfide nanoparticles including copper sulfide and copper sulfide nanoparticles have antimicrobial properties and conductive properties.
The present invention can be used for military clothes, equipment, tents, and instruments.
Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.
A camouflage fabric with near infrared ray reflectance adjusting characteristics may contain copper sulfide nanoparticles or metal sulfide nanoparticles including copper sulfide at a ratio of about 0.1 wt % to about 3 wt % with respect to the weight of the fabric to reduce Near Infrared Ray Reflectance (NIRR).
That is, a conductive polymer in which copper sulfide nanoparticles or metal sulfide nanoparticles including copper sulfide are coordinate-bonded may be used. The conductive polymer in which copper sulfide nanoparticles or metal sulfide nanoparticles including copper sulfide are coordinate-bonded may be an electroconductive material that contains metal sulfide nanoparticles including copper sulfide bonded to a polymer matrix containing a group selected from mercapto, thiocarbonyl, quaternary ammonium salt, and isocyanate.
Also, the polymer matrix may be selected from polyester, polyamide (nylon), polyacrylonitrile, cotton, polyvinylchloride resin, and amino resin.
In one embodiment, a method of manufacturing electroconductive polyamide in which copper sulfide nanoparticles or metal sulfide nanoparticles including copper sulfide are coordinate-bonded to a polyamide (nylon) polymer matrix having a mercapto radical introduced with the polymer matrix may include a first process that is a polyamide reforming process in which a silane coupling agent of about 500 mg/L to about 5 g/L that is a molar reaction product such as silane containing a mercapto group and an azole compound is prepared in an aqueous solution as a preprocessing agent, and then polyamide of about 25 wt % immerses in the prepared preprocessing agent solution of about 100 wt % at a temperature of about 55° C. for about 60 minutes, and then a non-reaction product is washed out using sodium hydroxide solution of about 1 wt %, and then dried at an atmospheric temperature of about 80° C. for about one hour, and then cooled to a room temperature to reform polyamide into a polyamide polymer matrix having a mercapto group, and a second process that is a conductivity forming process in which a polyamide yarn absorbed with or coordinate-bonded to the mercapto group immerses in a metal nanoparticle composition including copper sulfide, and then dye treatment is performed at a temperature of about 55° C. for about 120 minutes to give conductivity to the polyamide yarn.
Here, in the second process, the conductive metal sulfide nanoparticle composition including copper sulfide or copper sulfide nanoparticles may include about 1 wt % to about 30 wt % copper salt, nickel salt and zinc salt, about 0.05 wt % to about 5 wt % phenyl compound reductant, about 0.05 wt % to about 1.5 wt % low molecular weight sulfide, about 0.1 wt % to about 10 wt % water soluble amines, about 1 wt % to about 10 wt % thio compound, about 0.01 wt % to about 1 wt % thio stabilizer, and about 2 wt % to about 5 wt % pH-conditioning agent with respect to 100 wt % of the polyamide fiber to be coated.
The conductive polymer in which metal sulfide nanoparticles including copper sulfide or copper sulfide nanoparticles are coordinate-bonded may be a conductive yarn that gives electroconductivity to fiber while maintaining the characteristics of the synthetic fiber. The conductive polymer may absorb near infrared ray in a near infrared ray spectrum of about 720 nm to about 1,500 nm.
Also, a fabric using the conductive polymer may be easy to control conductivity according to the type and content of conductive metal elements and control conductivity according to the thickness of the base material fiber while maintaining intrinsic characteristics of the synthetic fiber. Accordingly, the fabric enables the use of various existing looms in terms of weaving of the fabric, and thus may be very useful for manufacturing of the filaceous camouflage fabric.
Also, the camouflage fabric according to the embodiment of the present invention needs to be designed to have near infrared ray reflectance similar or equal to any surrounding background or area.
In order to achieve an optimal result in the near infrared ray application, a target must not have too high or too low near infrared ray reflectance compared to the near infrared ray reflectance of surrounding environments.
This is because under too high near infrared ray reflectance compared to that of surrounding environments, when observed by a night vision device, a bright image is generated. On the contrary, under too low near infrared ray reflectance compared to that of surrounding environments, when observed by a night vision device, a dark image may be generated.
Accordingly, an optimal level of the near infrared ray reflectance needs to vary according to the surroundings.
The geomorphic elements may have different reflection signals based on the chemical constitution thereof.
Typically, fabrics useful for the military clothes and equipment may be formed of polyester, polyamide, or blended yarns of synthetic fiber thereof and cotton.
Also, synthetic polymer polyamide (nylon) and polyester fiber is known as a material having a high near infrared ray reflectance of about 85% to about 90% in the visible ray and near infrared ray regions of about 600 nm to about 2,000 nm.
Consequently, the near infrared ray reflectance of polyester and polyamide clothes and equipment in a battlefield needs to be reduced closely to the near infrared ray reflectance of the surroundings.
For example, the near infrared ray reflectance of temperate leaves are measured to be typically about 35%, and the near infrared ray reflectance of eremophilous leaves may rise to about 70%.
Since clothes and equipment manufactured from the camouflage fabric in accordance with the topography destroys the silhouette of a wearer when viewed from the near infrared ray spectrum range, the clothes and equipment may effectively camouflage the wearer from a near infrared observation equipment that uses a night vision device.
Accordingly, in a modern war, it is very important to manufacture a military camouflage fabric that is designed to have a near infrared ray reflectance similar or equal to those of surrounding objects having different natural near infrared ray reflectances in the near infrared ray spectrum region of about 720 nm to about 1,500 nm in addition to the color camouflage of the wavelength band of the visible ray spectrum.
The military camouflage fabric with near infrared ray reflectance adjusting characteristics may include at least a first multifilament yarn and a second multifilament yarn to more accurately adjust the near infrared ray reflectance characteristics, which will be described in detail below.
The first multifilament yarn may have a total of about 250 denier to about 350 denier in which conductive polymer multifilament yarn of about 30 denier to about 150 denier containing metal sulfide nanoparticles including copper sulfide or copper sulfide nanoparticles and a blended yarn of about 150 denier to about 300 denier such as polyester and cotton, polyester and rayon, or nylon multifilament without a component that can control the near infrared ray reflectance characteristics are blended at about 300 T/M to about 400 T/M by a twisting machine. The second multifilament yarn may have a total of about 250 to about 350 denier in which polyamide (nylon) cotton, rayon, and polyester substantially without a component that can control the near infrared ray reflectance characteristics are blended at about 300 T/M to about 400 T/M by a twisting machine. The military camouflage fabric with near infrared ray reflectance adjusting characteristics may be manufactured by weaving the first multifilament yarn and the second multifilament yarn into plain weaves or fancy plain weave as a warp and a weft at various blending ratios by a loom, and then printing a pattern and a hue of a visible ray region have a color, a chroma, and a brightness which are difficult to distinguish from surrounding objects on the surface of the manufactured fabrics in order to show a similar level of camouflage effect at day and night times.
In this case, a vat dye and a disperse dye may be used for blending of polyester and cotton, and a reactive vinyl sulfone or vat dye may be used for blending of polyamide and cotton in order to print the camouflage fabrics. The camouflage fabrics according to the embodiment of the present invention may be used to manufacture clothes, gears, tents, and military equipment which have camouflage exteriors in terms of near infrared ray reflectance monitored by night vision devices.
Accordingly, clothes manufactured from the camouflage fabrics may provide a camouflage effect of near infrared ray that substantially conceals a wearer from the detection by night vision devices such as night vision goggles and image amplification converters.
Tables 1 to 8 below regulate the near infrared ray reflectance of military camouflage fabrics of each country by color.
Hereinafter, embodiments of the present invention will be described in more detail.
First, a method of manufacturing a nylon conductive yarn containing metal sulfide nanoparticles including copper sulfide will be described.
An aqueous silane coupling agent of about 1,000 mg/L which is an equimolar reaction product with imidazole and 3-mercaptopropyltrimethoxysilane was prepared as a preprocessing agent.
About 30 denier nylon filament yarn of about 50 Kg was dipped in water bath of about 200 Kg containing the preprocessing agent solution at a temperature of about 55° C. for about 60 minutes, and then non-reaction products was washed out with sodium hydroxide solution of about 1 wt %. Thereafter, the nylon filament yarn was dried at an atmospheric temperature of about 80° C. for about one hour.
Thereafter, the nylon filament yarn was cooled to a room temperature, and then was dyed with metal sulfide nanoparticles composition including copper sulfide or copper sulfide nanoparticles including compositions of Table 9 as postprocessing agent at a temperature of about 55° C. for about 120 minutes to form a nylon conductive yarn containing nanoparticles including copper sulfide or copper sulfide nanoparticles.
The properties of the conductive nylon fiber manufactured according to <Embodiment 1> and <Embodiment 2 22 was measured as follows. The measurement results are shown in Table 10 below.
<Manufacturing Example 3> and <Manufacturing Example 4> below relate to a method of manufacturing the first multifilament yarn and the second multifilament yarn that can control the near infrared ray reflectance using an electroconductive nylon filament yarn in which metal sulfide nanoparticles including copper sulfide nanoparticles are coordinate-bonded according to <Embodiment 1>.
The polyamide (nylon) conductive yarn manufactured in <Embodiment 1> in which metal sulfide nanoparticles including copper sulfide with a total of metal content of about 2.84 wt % having about 30 denier, i.e., resistivity of about 2×10-2 Ωcm are coordinate-bonded and a TC blending yarn of about 60% polyester and about 265.5 denier and a TC blended yarn of about 265.6 denier, i.e., 40 Nc/2 blending of 60% polyester and 40% scoured cotton yarn were twisted at 360 T/M to manufacture the first multi filament yarn of about 295.6 denier that can adjust the near infrared ray reflectance characteristics.
A 40 Nc 1 blended yarn of polyester (60%) and scoured cotton yarn (40%) and a high flexible polyester filament yarn of about 150 denier were twisted at 360 T/M to manufacture the second multifilament yarn of about 282.8 denier without a component that can adjust the near infrared ray reflectance characteristics.
Hereinafter, various embodiments in which the first multifilament yarn of <Manufacturing Example 3> and the second multifilament yarn <Manufacturing Example 4> are designed into plain weaves or fancy plain weaves as a warp and a weft by a loom to variously control the near infrared ray reflectance will be described.
As a warp of the camouflage, two strands of the first filament yarns of 295.6 denier twisted in <Manufacturing Example 3> and one strand of the second filament yarn of 282.8 denier twisted in <Manufacturing Example 4> were alternately woven into a fancy plain weave at a ratio of 2:1 and a warp density of about 170 strands/5 cm, and as a weft, one strand of the first filament yarn of 295.6 denier twisted in <Manufacturing Example 3> and two strands of the second filament yarns of 282.8 denier twisted in <Manufacturing Example 4> were alternately woven into a fancy plain weave at a ratio of 1:2 and a weft density of about 160 strands/5 cm to weave a camouflage fabric with a weight of about 225 g/m2.
<Embodiment 2> to <Embodiment 10> of a fabric weaving design of a camouflage fabric are shown in Table 11 below.
In order to achieve a desired camouflage in both visible ray and near infrared ray, the fabric woven in <Embodiment 1> was continuously refined using a non-ionic active agent, and then was directly printed at four degrees into khaki, green, brown, and black using a typical vat dye by an automatic printing machine. The saturated steaming was performed on the printed fabric at a temperature of about 120° C. for about 3 minutes, and then continuous rinse and final set were performed. The measurement results of this camouflage fabric are shown in graph of
The fabric woven in <Embodiment 1> was continuously refined using a non-ionic active agent, and then was directly printed at five degrees into charcoal, dark olive, green, land color, dark wood, and forest green using a typical vat dye by the automatic printing machine.
The saturated steaming was performed on the printed fabric at a temperature of about 120° C. for about 3 minutes, and then continuous rinse and final set were performed. The measurement results of this camouflage fabric are shown in graph of
As shown in an actually-measured near infrared ray reflectance curve of graph of
The present invention can be used for military clothes, equipment, tents, and instruments.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2011-0068211 | Jul 2011 | KR | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/KR2012/005472 | 7/10/2012 | WO | 00 | 1/13/2014 |
