Methods for preparing functional textile that harness ultraviolet light essential for vitamin d synthesis

Abstract

A fabric is provided. The fabric includes an exterior side and an interior side, wherein the exterior side and the interior side have a silver nanoparticle coating that selectively absorbs and transmits UV light.

Description

TITLEMETHODS FOR PREPARING FUNCTIONAL TEXTILE THAT HARNESS ULTRAVIOLET LIGHT ESSENTIAL FOR VITAMIN D SYNTHESISCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 461,391 filed April 24, 2023, which is incorporated herein by reference in its entirety.BACKGROUND

[0002] Vitamin D is essential for the body’s health. For example, Vitamin D plays an important role in balancing calcium in the blood and the bones. Further, Vitamin D is integral to the process of building and maintaining healthy bones, which also requires calcium and phosphorus. Although Vitamin D is required for a variety of important functions, Vitamin D deficiency is a global issued that may affect over 1 billion people. Studies have determined that approximately 86% of people in Middle Eastern countries suffer from a Vitamin D deficiency.

[0003] Vitamin D deficiencies are linked to various metabolic disorders and can be detrimental to one’s health. Severe Vitamin D deficiency limits calcium and phosphorus absorption in the body. A reduced absorption ability may lead to reduced calcium levels in the blood, causing, for example, muscle weakness, fatigue, and depression. In another example, reduced calcium levels in the blood may cause the body to balance calcium levels by absorbing calcium from the bones. While this may balance calcium levels in the blood, reduced calcium levels in bones could compromise one’s bone health, leading to an increased chance of bone fractures. Vitamin D is made when ultraviolet light (“UV”) rays react with a compound in the skin. However, many people prefer to wear clothing that covers the majority of their skin, which prevents UV rays from reacting with their skin to produce Vitamin D.

[0004] Thus, systems and methods are needed that allow UV rays to be transmitted and absorbed into the skin.SUMMARY

[0005] In light of the disclosure herein and without limiting the disclosure in any way, in a first aspect of the present disclosure, which may be combined with any other aspect listed herein unless specified otherwise, a fabric is provided. The fabric includes an exterior side andan interior side. The exterior side and the interior side have a silver nanoparticle coating that selectively absorbs and transmits UV light.

[0006] In accordance with a second aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the silver nanoparticle coating on the exterior side is a first silver nanoparticle coating.

[0007] In accordance with a third aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the silver nanoparticle coating on the interior side is a second silver nanoparticle coating.

[0008] In accordance with a fourth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the UV light is UVB light.

[0009] In accordance with a fifth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the silver nanoparticle coating includes a plurality of silver nanoparticles, and each of the plurality of silver nanoparticles are 20 to 90 nanometers.

[0010] In accordance with a sixth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, a thickness of the fabric is approximately 0.58 millimeters.

[0011] In accordance with a seventh aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the fabric forms at least a portion of a garment configured to be worn.

[0012] In accordance with an eight aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the interior side faces a wearer’s skin.

[0013] In accordance with a ninth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the silver nanoparticle coating selectively absorbs and transmits UV light to the wearer’s skin.

[0014] In accordance with a tenth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, a method of manufacturing a fabric having a silver nanoparticle coating that selectively absorbs and transmits UV light is provided. The steps include synthesizing a silver nanoparticle solution; applying a first solution to the fabric; and applying the silver nanoparticle solution to the fabric.

[0015] In accordance with an eleventh aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the method of manufacturing includes calculating a volume fraction of silver nanoparticles.

[0016] In accordance with a twelfth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the first solution is 1 M NaOH, and the first solution is prepared in water.

[0017] In accordance with a thirteenth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, synthesizing the silver nanoparticle solution produces 1 g / L AgNOs, and the silver nanoparticle solution is prepared in water.

[0018] In accordance with a fourteenth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the method of manufacturing includes drying the fabric for at least 24 hours after spraying the fabric with the first solution and the silver nanoparticle solution.

[0019] In accordance with a fifteenth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the fabric is treated prior to applying the silver nanoparticle solution.

[0020] In accordance with a sixteenth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the fabric is treated using atmospheric plasma prior to applying the silver nanoparticle solution.

[0021] In accordance with a seventeenth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the silver nanoparticle solution is applied using a spray gun.

[0022] In accordance with an eighteenth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, to synthesize the silver nanoparticle solution, a silver nanoparticle precursor is added to a solvent solution having a binder and a polymer.

[0023] In accordance with a nineteenth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the polymer is PEG.

[0024] In accordance with a twentieth aspect of the present disclosure, which may be used in combination with any other aspect listed herein unless stated otherwise, the binder is configured to link the silver nanoparticle solution to the fabric.

[0025] Additional features and advantages of the disclosed method and apparatus are described in, and will be apparent from, the following Detailed Description and the Figures. The features and advantages described herein are not all-inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the figures and description. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and not to limit the scope of the inventive subject matter.BRIEF DESCRIPTION OF THE FIGURES

[0026] Understanding that figures depict only typical embodiments of the invention and are not to be considered to limit the scope of the present disclosure, the present disclosure is described and explained with additional specificity and detail through the use of the accompanying figures. The figures are listed below.

[0027] Figure 1 illustrates a textile that selectively absorb UV light, according to an example embodiment of the present disclosure.

[0028] Figure 2 illustrates a textile having an interior face and an exterior face, according to an example embodiment of the present disclosure.

[0029] Figure 3 illustrates a relationship between an absorption coefficient and a volume fraction of silver nanoparticles, according to an example embodiment of the present disclosure.

[0030] Figure 4 illustrates a process of applying a plurality of silver nanoparticles onto a textile, according to an example embodiment of the present disclosure.

[0031] Figure 5 illustrates a comparison between a transmittance percentage and wavenumber for a number of textiles, according to an example embodiment of the present disclosure.

[0032] Figure 6, views (a) to (d), illustrate scanning electron microscopy results of a textile before and after treatment, according to an example embodiment of the present disclosure.

[0033] Figure 7, views (a) to (d), illustrate scanning electron microscopy results of varying magnification of a textile after treatment, according to an example embodiment of the present disclosure.

[0034] Figure 8, views (a) to (e), illustrate energy dispersive mapping results of a distribution of a plurality of silver nanoparticles on a textile, according to an example embodiment of the present disclosure.

[0035] Figure 9, views (a) to (b), illustrate UV-visible absorption and transmittance spectra of a textile before and after treatment, according to an example embodiment of the present disclosure.

[0036] Figure 10, views (a) to (c), illustrate UV-visible absorption and transmittance spectra and scanning electron microscopy results after washing a textile, according to an example embodiment of the present disclosure.

[0037] Figure 11, views (a) to (d), illustrates a coating system applied to selected areas of a garment, according to an example embodiment of the present disclosure.DETAILED DESCRIPTION

[0038] The present disclosure generally relates to systems and methods that selectively allow UV rays to be transmitted and absorbed into the skin. As previously introduced, many people prefer to wear clothing that covers the majority of their skin. However, many clothing fabrics prevent the transmission of UV rays to one’s skin, thereby preventing the production of Vitamin D. As discussed herein, silver nanoparticles (i.e., Ag nanoparticles) provide optical properties suitable for the fabrics manufactured according to the present disclosure. In an example embodiment, system and methods provide a process of manufacturing fabrics that are used for clothing that selectively absorb UV light from the sun, which can be transmitted to the skin. While the manufactured fabric allows selective penetration of UV light, the fabric simultaneously protects the skin from direct sunlight, which may be harmful.

[0039] The disclosure details the preparation methods and application for harnessing useful UV light essential for Vitamin D synthesis in the skin. The fabric is used to manufacture clothing that allows selective penetration of UVB light so that, for example, a wearer’s skin is exposed to sufficient UVB light to permit the production of Vitamin D without exposing the skin directly to sunlight. This is advantageous for people who are required or prefer to wear clothing that covers the skin (e.g., a burqa, abaya, or Hijab). Figure 1 illustrates a textile that selectively absorb UV light, according to an example embodiment of the present disclosure. The textile 100 includes a plurality of silver nanoparticles 102 disposed on the surface.

[0040] Light from the sun includes various types of UV rays, including UVA 104, UVB 106, and UVC 108. Each type of UV ray corresponds to a specific wavelength. As shown inthe example embodiment of Figure 1, UVC 108 is primarily absorbed by the ozone layer, and thus does not reach the textile 100. In contrast, UVA 104 and UVB 106 reach the textile 100 and interact with the plurality of silver nanoparticles 102. The plurality of silver nanoparticles 102 function to (1) reflect UVA 104, (2) reflect a portion of UVB 108, and (3) absorb a portion of UVB 108, which is then transmitted through the textile 100 to the interior surface. The respective surfaces of the textile 100 are further explained in reference to Figure 2.

[0041] Figure 2 illustrates a textile having an interior face and an exterior face, according to an example embodiment of the present disclosure. The textile 200 includes an exterior face 210 and an interior face 212. In Figure 2, the exterior face 210 includes a plurality of silver nanoparticles 202 and the interior face 212 includes a plurality of silver nanoparticles 202. In an illustrative example, the textile 200 forms at least a portion of a garment. The exterior face 210 faces the sun and the interior face 212 faces the wearer’s skin. As the exterior face 210 is exposed to sunlight, it is exposed to UV light (as shown in Figure 1). However, in an example, the plurality of silver nanoparticle 202 may only absorb a portion of the UV light (e.g., UVB light), which is then transmitted through the textile 200 to the interior face 212. Finally, the plurality of silver nanoparticles 202 on the interior face 212 absorb the UV light and reflects the UV light toward the skin of the wearer, thereby facilitating UV absorption for Vitamin D production.

[0042] Further, while not shown in Figure 2, the textile 200 may include a sensor disposed in a number of positions. For example, the sensor may be disposed between the exterior face 210 and the interior face 212. In another example, the sensor may be disposed on the interior face 212 of the textile 200. The sensors may electronically regulate the amount of total light to alert the wearer about achieving a suitable daily charge of the light.

[0043] To manufacture the textile having a silver nanoparticle coating, the method may comprise the following steps: (1) providing a UV absorbing and transmitting fabric that contains a nanometer meter-scale silver nanoparticle coating; (2) carrying out surface treatment on both sides and within the textile layer of the fabric to ensure an appropriate dispersion of the silver nanoparticles, and (3) providing two coating methods suitable for dark and light color fabrics.

[0044] The fabric may be prepared by treating it with a silver-based coating comprising silver nanoparticles in two different ways. A first method is used to prepare light-colored fabrics. Namely, a precursor for silver nanoparticles (e.g., pre-made silver nanoparticles) is added to a solvent solution. The solution may include a binder and a polymer. The polymer, which can be polyethylene glycol (“PEG”) or cellulose acetate, is used to functionalize thesilver nanoparticles via the polymer chains. Once functionalized, the silver nanoparticles are linked to the textile via the binder, thereby creating a silver nanoparticle coating.

[0045] A second method may be used to prepare dark or black-colored fabrics. In dark color fabrics, the silver nanoparticles attach directly to the textile via functional groups (e.g., hydroxyl). Thus, the silver nanoparticles are directly deposited on the textile using the silver precursor (i. e. , AgNOs) without a binder attached by functional groups. The garment comprises a plurality of sections that comprises the entire fabric, including an exterior coating of silver nanoparticles and an interior coating of silver nanoparticles.

[0046] In a detailed example embodiment, the method includes (1) a reduction step, (2) a spraying process, (3) an application process, and (4) a characterization process. The coating system includes a solvent, a binder, and a polymer. The polymer may include polyethylene glycol (“PEG”) or a cellulose acetate solution. In the first step, the absorption coefficient and the silver nanoparticle volume fraction in the coating system are calculated. Figure 3 illustrates a relationship between an absorption coefficient and a volume fraction of the silver nanoparticles, according to an example embodiment of the present disclosure. In one example, the silver nanoparticles may range from 20 to 90 nanometers on the entire textile, including the interior and exterior coating of silver nanoparticles, with an average size of 75 nanometers. The size of the silver nanoparticles may advantageously have a high toxicity toward bacteria. Further, the silver nanoparticles may be separated by a distance (i.e., textile thickness) of 0.58 millimeters.

[0047] Next, the reduction process may be executed on black or dark-colored textiles. In atypical synthesis, 250 ml of 1 g / L AgNOs and 1 M NaOH is prepared separately in ultrapure (“UP”) water. Then, either black or dark textile is sprayed with 1 M NaOH, followed by the AgNOs solution on both sides of the textile. The formation of silver nanoparticles can be identified by the change of the color to brown, which confirms the reduction process. Finally, the textile is air-dried for 24 hours to ensure full reduction. Then, it is washed with UP water and air-dried for another 24 hours. The textile may have a thickness of 0.58 millimeters, and the silver nanoparticles may range from 20 to 90 nanometers on both the interior and exterior of the textile.

[0048] In another step, the method includes a spraying process. The spraying process can be used on white or light-colored textiles. For synthesis, 1 gram of PEG is dissolved in UP water and 0.1 grams of silver nanoparticles are added to the previous solution. The solution is sonicated for 30 minutes in an UP bath. White or light-colored textiles are sprayed with 1 MNaOH, followed by spraying with silver nanoparticle solution. Again, the textile is air-dried for 24 hours.

[0049] The silver nanoparticles are then applied to the textile surface in the application step. The textile surface is treated using atmospheric plasma before the silver nanoparticle coating is applied to ensure textile roughness and permanent treatment. Then, the silver nanoparticle coating is applied with a nano-spray gun for a uniform distribution. Figure 4 illustrates a process of applying a plurality of silver nanoparticles onto a textile, according to an example embodiment of the present disclosure. As shown in Figure 4, a user 414 applies the silver nanoparticle coating to a textile 400 using an electronic spay gun 416. However, it should be appreciated that the silver nanoparticle coating can be applied in any number of ways to achieve the desired distribution.

[0050] The method of the example embodiment also includes a characterization process. Namely, the textile materials are characterized before and after the treatment by Fourier-transform infrared spectroscopy (“FTIR”), which is recorded using an FTIR spectrometer (e.g., FTIR-650, Australia). These measurements can be used to study the changes on the textile surface. Further, scanning electron microscopy (“SEM”) is used on the textile before and after treatment using, for example, an FEI Quanta 650 FEG at different magnifications. Energy dispersive (“EDS”) mapping is used to study morphology and the silver nanoparticle distribution on the textile fiber. The UV-visible absorption and transmittance spectra of textile before and after treatment are obtained by a split-beam UV- visible spectrophotometer (e.g., YK Scientific, UV1810 / UV1810S, China). Finally, to ensure the permeant effect of the coating on the textile, the treated textile is washed 20 times at 80 °C for 1 hour.

[0051] Figures 5 to 11 illustrate example results of the characterization process. Figure 5 characterizes the wavenumber versus the transmittance percentage for a number of textiles, including (1) an untreated textile, (2) a textile treated with silver nanoparticles and a binder, (3) a textile treated with silver nanoparticles and PEG, and (4) a textile treated with silver nanoparticles, PEG, and a binder. Figure 5 shows that the untreated textile exhibits the lowest transmittance percentage at each wavenumber while the textile treated with the silver nanoparticles, PEG, and a binder exhibits the largest transmittance percentage at each wavenumber.

[0052] Figure 6, views (a) to (d), illustrate scanning electron microscopy results of a textile before and after treatment. Namely, views (a) and (b) illustrate SEM results of the textile before treatment and views (c) and (d) illustrate SEM results of the textile after treatment.Figure 7, views (a) to (d), illustrate scanning electron microscopy results of varying magnification of a textile after treatment. As shown in view (d), the silver nanoparticles are coated onto the fabric. Figure 8, views (a) to (e), illustrate energy dispersive mapping results of a distribution of a plurality of silver nanoparticles on a textile. The results of Figure 8 may be used, for example, to study the morphology and the distribution of solver nanoparticles on the textile fibers. Figure 9, views (a) and (b), illustrate UV- visible absorption and transmittance spectra of a textile before and after treatment. Figure 9 includes a treated and untreated textile. Figure 10, views (a) to (c), illustrate UV- visible absorption and transmittance spectra and scanning electron microscopy results after washing a textile.

[0053] Figure 11, views (a) to (d), illustrate a coating system applied to selected areas of a garment. For example, the silver nanoparticle coating system may be selectively applied to areas of the garment that are more directly exposed to sunlight. In other words, a portion of the garment may include the coating system rather than coating the entire garment. In Figure 11, view (a), these areas that are selectively covered in the coating system may correspond to the shoulders and arm area of the garment. Further, in Figure 11, view (d), the entire garment may be coated when the entire garment is exposed to sunlight (e.g., a scarf).

[0054] Although the method has been described in certain specific aspects, many additional modifications and variations would be apparent to those skilled in the art. In particular, any of the various processes described above can be performed in alternative sequences and / or in parallel in order to achieve similar results in a manner that is more appropriate to the requirements of a specific application. It is therefore to be understood that the present disclosure can be practiced otherwise than specifically described without departing from the scope and spirit of the present embodiments. Thus, embodiments of the present invention should be considered in all respects as illustrative and not restrictive. It will be evident to the annotator skilled in the art to freely combine several or all of the embodiments discussed here as deemed suitable for a specific application of the invention. Throughout this disclosure, terms like “advantageous”, “exemplary” or “preferred” indicate elements or dimensions which are particularly suitable (but not essential) to the invention or an embodiment thereof, and may be modified wherever deemed suitable by the skilled annotator, except where expressly required. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their equivalents.

Claims

CUAIMSThe invention is claimed as follows:

1. A fabric comprising : an exterior side; and an interior side, wherein the exterior side and the interior side have a silver nanoparticle coating that selectively absorbs and transmits UV light.

2. The fabric of Claim 1, wherein the silver nanoparticle coating on the exterior side is a first silver nanoparticle coating.

3. The fabric of Claim 1, wherein the silver nanoparticle coating on the interior side is a second silver nanoparticle coating.

4. The fabric of Claim 1, wherein the UV light is UVB light.

5. The fabric of Claim 1, wherein the silver nanoparticle coating comprises a plurality of silver nanoparticles, wherein each of the plurality of silver nanoparticles are 20 to 90 nanometers.

6. The fabric of Claim 1, wherein a thickness of the fabric is approximately 0.58 millimeters.

7. The fabric of Claim 1, wherein the fabric forms at least a portion of a garment configured to be worn.

8. The fabric of Claim 7, wherein the interior side faces a wearer’s skin.

9. The fabric of Claim 8, wherein the silver nanoparticle coating selectively absorbs and transmits UV light to the wearer’s skin.

10. A method of manufacturing a fabric having a silver nanoparticle coating that selectively absorbs and transmits UV light comprising the steps of: synthesizing a silver nanoparticle solution; applying a first solution to the fabric; and applying the silver nanoparticle solution to the fabric.

11. The method of manufacturing of Claim 10, further comprising calculating a volume fraction of silver nanoparticles;12. The method of manufacturing of Claim 10, wherein the first solution is 1 M NaOH, and wherein the first solution is prepared in water.

13. The method of manufacturing of Claim 11, wherein synthesizing the silver nanoparticle solution produces 1 g / L AgNOs, and wherein the silver nanoparticle solution is prepared in water.

14. The method of manufacturing of Claim 10, further comprising drying the fabric for at least 24 hours after spraying the fabric with the first solution and the silver nanoparticle solution.

15. The method of manufacturing of Claim 10, wherein the fabric is treated prior to applying the silver nanoparticle solution.

16. The method of manufacturing of Claim 15, wherein the fabric is treated using atmospheric plasma prior to applying the silver nanoparticle solution.

17. The method of manufacturing of Claim 15, wherein the silver nanoparticle solution is applied using a spray gun.

18. The method of manufacturing of Claim 10, wherein, to synthesize the silver nanoparticle solution, a silver nanoparticle precursor is added to a solvent solution having a binder and a polymer.

19. The method of manufacturing of Claim 18, wherein the polymer is PEG.

20. The method of manufacturing of Claim 18, wherein the binder is configured to link the silver nanoparticle solution to the fabric.

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