Multilayer multifunctional thermal insulation material

Abstract

A thermal insulation material for a garment is provided that includes a solar energy transmissive shell fabric, a solar energy transmissive insulation layer, and a solar energy absorbing liner fabric. The solar energy absorbing liner fabric includes a plurality of thermal insulation elements coupled to the liner fabric, such as a weighted average thermal emittance of less than 0.8 (or 80%). The thermal insulation elements include a low thermal emittance layer and a high solar energy absorptivity layer.

Description

Cross-reference to related applications

[0001] This application claims priority to U.S. Provisional Application No. 63 / 539,062, filed September 18, 2023. The entire contents of the above application are hereby incorporated herein by reference. Technical Field

[0002] This disclosure generally relates to a base material (e.g., fabric) for use in human body equipment and other products with design performance characteristics, and particularly to a technical device (e.g., clothing) that utilizes an insulating element coupled to the base material to limit the transfer of heat from or through the base material to the environment, and additionally captures solar radiation, converts it into heat, and directs the heat to the inside of the base material and / or the wearer of the clothing. Background Technology

[0003] Thermally insulating heat-reflective materials typically take the form of a single layer of thin metal film or discretely patterned metal elements bonded to a base material via adhesive or other means. This type of heat-reflective material is used as the inner surface of clothing (e.g., jackets). The thin metal film or patterned heat-reflective elements are arranged on the inner surface of the garment (e.g., the inward-facing surface) to reflect the wearer's body heat back into the garment or onto the body side of the garment, effectively retaining heat generated by the body and ensuring the wearer stays warm in cold environments. While such materials do improve insulation, there is a continuous need for new materials that can provide even better insulation. Attached Figure Description

[0004] The embodiments will be readily understood by referring to the accompanying drawings and the following detailed description. The embodiments are illustrated by way of example and are not intended to be limited to the figures in the drawings.

[0005] Figure 1 This is a schematic diagram of the insulation element coupled to the substrate material.

[0006] Figure 2 The graph shows the spectral power of solar radiation on the Earth's surface relative to wavelength, sourced from ASTM G173.

[0007] Figure 3 The graph shows the spectral power of thermal radiation emitted by a blackbody surface at a typical surface temperature as a function of wavelength, as illustrated by the Planck distribution.

[0008] Figure 4An experimental setup for thermal imaging and temperature measurement of a hot plate coated with a black polymer and upon which a metal plate is placed is shown. An infrared (IR) thermal imaging camera is used to measure the radiance emitted by the object (i.e., the total amount of energy emitted, reflected, and transmitted by the object). The camera software then converts the radiance into apparent temperature using the Planck distribution for thermal radiation. The apparent temperature reading is accurate only if the user inputs the correct emissivity (or thermal emissivity) of the object in the camera's operating settings. Alternatively, an IR camera with an emissivity set to 1 (i.e., an ideal "blackbody" emission source) can be used to measure an object maintained at a known actual temperature; in this scenario, the degree of match between the apparent temperature measured by the camera and the actual temperature of the object serves as an indicator of the object's thermal emissivity.

[0009] Figure 5 It shows the use of Figure 4 The results obtained by the thermal imaging device shown.

[0010] Figure 6 The graph illustrates the thermal emissivity as a function of wavelength for three different insulation elements: silver, the insulation element disclosed herein (e.g., a black metallized insulation element), and a black polymer insulation element. The percentage values ​​in the graph represent weighted average emissivity. .

[0011] Figure 7 The graph shows the solar absorptivity as a function of wavelength for three different insulation elements: silver, the insulation element disclosed herein (e.g., a black metallized insulation element), and a black polymer insulation element. The percentage values ​​in the graph represent weighted average absorptivity. .

[0012] Figure 8 A digital photograph of an embodiment in which the thermal insulation element of this disclosure (e.g., a black metallized thermal insulation element) has been applied to the fabric surface.

[0013] Figure 9 The following figures illustrate the relationship between the thermal emissivity and wavelength for two different fabrics: a black substrate fabric; and an insulation element (e.g., a black metallized insulation element) of this disclosure coupled to and covering 55% of the surface of the same black substrate fabric. The percentage values ​​in the figures represent weighted average emissivity. .

[0014] Figure 10 The following figures illustrate the relationship between solar energy absorption rate and wavelength for two different fabrics: a black substrate fabric; and an insulation element (e.g., a black metallized insulation element) of this disclosure coupled to and covering 55% of the surface of the same black substrate fabric. The percentage values ​​in the figures represent weighted average absorption rates. .

[0015] Figures 11A to 11B A schematic model of the establishment is depicted. Figure 11A ) and thermal resistance network ( Figure 11B This study aims to determine the influence of material and environmental parameters on the relative importance of thermal emissivity and solar absorptivity in textile insulation.

[0016] Figure 12 The following figures illustrate the variations in heat conducted to the skin relative to the solar energy component reaching the fabric, determined by thermal modeling, for three different textile fabrics: a black base fabric, the same black base fabric with 50% silver insulation elements on the outermost surface, and the same black base fabric with 50% of the insulation elements disclosed herein on the outermost surface. Fixed material and environmental parameters are shown at the top of the figures.

[0017] Figure 13 A schematic diagram of an experimental apparatus for measuring the heat trapped by a fabric is shown.

[0018] Figure 14 To utilize Figure 13 A graph showing the data collected by the experimental setup shown.

[0019] Figures 15A to 15H Examples of thermal insulation elements with discontinuous patterns disposed on the outer-facing surface of a base fabric according to various embodiments are shown.

[0020] Figures 16A to 16F Examples of thermal insulation elements with patterns disposed on the outer-facing surface of a base fabric according to various embodiments are shown.

[0021] Figure 17 Embodiments of an outer garment according to various embodiments are shown, the outer garment comprising a solar-transmitting shell fabric, a solar-transmitting heat-insulating layer, and a solar-absorbing lining fabric.

[0022] Figure 18 yes Figure 17 Detailed drawing of the solar transmission housing fabric shown.

[0023] Figure 19 yes Figure 17 Detailed drawing of the solar-absorbing lining fabric shown.

[0024] Figures 20A to 20D Four different lofted material structures are shown for testing purposes.

[0025] Figure 21 Various layered material structures are shown, along with experimental setups for measuring thermal performance under sunlight; the solar transmittance (τ) of the shell fabric and sheet insulation is also included. 太阳 ).

[0026] Figure 22 Four three-layer material structures (shell fabric - sheet insulation - lining fabric) are shown in a 0°C environment, exposed to 1000 W / m 2 Thermal properties under sunlight; all four material structures utilize 60g / m³ material with a thickness of 11.5 mm. 2 Polyester sheet insulation layer. Detailed Implementation

[0027] In the detailed description below, reference will be made to the accompanying drawings, which form part of this document, illustrating specific embodiments that may be implemented. It should be understood that other embodiments may be adopted, and structural or logical changes may be made, without departing from the scope of the invention. Therefore, the detailed description below should not be considered limiting, and the scope of the embodiments should be defined by the appended claims and their equivalents.

[0028] Various operations can be described sequentially as multiple discrete operations, and this descriptive approach helps to understand the implementation of the present invention; however, this descriptive order should not be interpreted as implying a sequential dependency between these operations.

[0029] The specification may use descriptive terms based on a specific perspective, such as "up / down," "back / front," and "top / bottom." Such descriptions are for discussion purposes only and are not intended to limit the application of the disclosed embodiments.

[0030] The terms “coupled” and “connected” and their derivatives may be used. It should be understood that these terms are not intended to be synonymous. Specifically, in a particular implementation, “connected” can be used to indicate that two or more elements are in direct physical contact with each other. “Coupled” can also indicate that two or more elements are in direct physical contact with each other. However, “coupled” can also indicate that two or more elements are not in direct contact with each other, but can still cooperate or interact with each other.

[0031] In this specific embodiment, phrases of the form "A / B" or "A and / or B" mean (A), (B), or (A and B). In this specific embodiment, phrases of the form "at least one of A, B, and C" mean (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C). In this specific embodiment, phrases of the form "(A)B" mean (B) or (AB), in other words, A is an optional element.

[0032] The specification may use the terms "implementation method" or "multiple implementation methods," each of which may refer to more than one identical or different implementation method. Furthermore, the terms "comprising," "including," "having," and similar terms are considered synonymous with respect to implementation methods.

[0033] Omni-Heat™ reflective materials work by reflecting thermal radiation back to the human body. Materials important for this performance include, but are not limited to, metals such as aluminum, silver, and gold. In addition to exhibiting high reflectivity in the wavelength range of 2.5 to 40 μm, these materials also exhibit low emissivity in the same wavelength range. In other words, these materials combine high thermal reflectivity with low thermal emissivity.

[0034] Mathematical analysis of the three main modes of heat transfer—conduction, convection, and radiation—reveals that all three modes share a common term: ΔT, which is the temperature difference between the material losing heat and the material / environment gaining heat. The relevant formulas are shown below.

[0035]

[0036]

[0037]

[0038] Referring to the above formula, This represents heat transfer caused by convection, where... The convective heat transfer coefficient, For surface temperature, The ambient temperature; This represents heat transfer caused by conduction, where... Thermal conductivity, The cross-sectional area where conduction occurs. The temperature of an object that has lost heat. The temperature of the object receiving heat; and This represents heat transfer caused by radiation, where Boltzmann's constant, For weighted average thermal emissivity, For surface area, The surface temperature, The temperature of an object or environment that receives heat.

[0039] Consider scenarios where the ambient temperature is lower than body temperature. Because clothing and footwear materials are worn close to the body, and there is some conductive heat transfer between the body and the materials worn on it, the temperature difference (ΔT) between the body and adjacent materials is typically smaller than the ΔT between the outermost material layer and the environment. Therefore, under certain conditions, such as when the ΔT between the outermost material layer and the environment is large, modifications to the material to limit heat transfer to the environment have a greater impact on the overall insulation effect than modifications to limit heat transfer between the body and the innermost or adjacent material layers.

[0040] In one implementation, a material with low thermal emissivity (e.g., a metal) can be applied to the outermost material layer to limit radiative heat transfer to the environment from or through the base material, providing clothing and footwear with enhanced thermal insulation. Aluminum can be used for this purpose. However, aluminum can oxidize and wear when exposed to the environment or as the outermost layer of clothing during use. The thermal emissivity of a material surface is the degree to which it effectively emits energy in the form of thermal radiation. Quantitatively, thermal emissivity is the ratio of the amount of thermal radiation emitted by a surface to the amount of radiation emitted by an ideal blackbody surface at the same temperature (as given by the Stefan-Boltzmann law). This ratio varies from 0 to 1 (e.g., 100%), where the emissivity of an ideal blackbody radiator surface is 1, while the emissivity of a surface that only reflects thermal radiation from the surrounding environment is 0.

[0041] In other embodiments, a low thermal emissivity layer may be provided on the inner-facing surface (e.g., the innermost surface of the base layer or liner). This inner layer may be provided as a supplement to or replacement for the low thermal emissivity material on the outermost material surface.

[0042] A protective polymer layer over a metal surface (such as aluminum) protects the metal from oxidation and abrasion. Unfortunately, the polymer coating has a high thermal emissivity, which negates the effect of placing the low thermal emissivity metal on the outside of the garment (i.e., to minimize radiant heat loss to the surrounding environment to enhance the garment's insulation). Given these observations, the conventional practice is to place the metal elements on the inside of the garment, as is done with garments employing Omni-Heat™ Reflective technology.

[0043] However, in one embodiment, the inventors disclose a multilayer structure of a metal (e.g., aluminum) with a polymer coating, which collectively provides a multilayer insulation element that unexpectedly exhibits a low thermal emissivity compared to the base material used in garment manufacturing. As described in the “Examples” section below, tests on this multilayer structure unexpectedly showed that the weighted average emissivity of the multilayer insulation element was approximately 0.1 (i.e., 10%) (0.1 is considered low since the emissivity range is 0 to 1), for example, 0.07–0.13 (i.e., 7% to 13%). These insulation elements were coupled to the outside of different base fabrics and tested using the standard hot plate method. Even at 30% surface coverage, these insulation elements significantly and unexpectedly increased the thermal resistance of different base fabrics by 20% to 67% (see Table 1).

[0044] Furthermore, by adding colorants to the protective polymer overlay, solar radiation absorption can occur, enhancing the insulation capabilities of the multilayer element. As used herein, the term "colorant" refers to a substance added to alter the color of a material, such as a high solar absorptivity layer, like a polymer overlay. Most colorants can be classified as dyes or pigments, or combinations thereof. For example, black colorants achieve the highest solar absorptivity (e.g., energy absorption at wavelengths from 0.3 to 2.5 µm), resulting in significantly enhanced insulation performance in the presence of sunlight (direct or diffused sunlight) when such insulating elements are applied to the outer surface of clothing. With a surface coverage of 55%, this insulating element increased the thermal resistance of different base fabrics by 15% to 73% (see Table 2), which is significant and unexpected.

[0045] In some embodiments, a colorant may be added to the solar absorption layer (e.g., a polymer) in an amount of 3% to 10% by weight, for example, about 5% to 8% by weight.

[0046] In addition, such as Figure 14 The results demonstrate that the insulation element can unexpectedly function as a solar energy collector, absorbing more heat and conducting it to the coupled base fabric and the underlying insulation layer, and retaining this heat for a longer period of time compared to base fabrics with similar solar absorption rates.

[0047] In other embodiments (discussed in more detail below), the function of the thermal insulation element can be provided by various elements that may be distributed on different surfaces of the garment or located on / between different layers of the garment.

[0048] Since black colorants are typically emissive, those skilled in the art might expect that the increase in absorption rate would be offset by an increase in the thermal emissivity of the black colorant (e.g., emissivity at wavelengths of 5 to 40 µm). However, the test results unexpectedly showed that this was not the case. Even with the addition of a black colorant to the polymer overlay, the insulating element was still able to reduce the overall average thermal emissivity of the base fabric, resulting in an increase in insulation performance.

[0049] In another embodiment, a photochromic colorant can be used in the polymer coating layer, which changes from transparent to colored (e.g., black) upon exposure to sunlight, thereby minimizing emissivity in the absence of sunlight and maximizing solar energy absorption under sunlight. Photochromic colorants can be classified into P-type and T-type. P-type photochromic colorant systems can change color in all directions with different wavelengths of light. A P-type system changes color when exposed to a specific wavelength range and maintains this state after the irradiation stimulus is removed. It only reverts to its original color when exposed to another set of different wavelengths of light. Alternatively, if light can only drive a change in a single direction, it exhibits T-type properties. A T-type system can fade back to its original state through thermal back-reaction after no longer being exposed to a light source. Reversibility is an important aspect of both types of photochromism; for example, photosensitive materials that undergo inherently irreversible changes may not be considered photochromic. Real-world colorants may not always meet the strict definitions of these two properties, but most can still be easily categorized. Examples of T-type colorants disclosed herein include, but are not limited to, spiropyran, spiroxazine, and naphthopyran. Examples of P-type colorants disclosed herein include, but are not limited to, diarylethylene and fulgide.

[0050] Reference Figure 1 The disclosed thermal insulation material 10 comprises a base fabric 20 having one or more performance characteristics. The base fabric 20 has an outward-facing surface 12 (e.g., the surface facing outward relative to the wearer's body) and an inward-facing surface 13 (e.g., the surface facing inward relative to the wearer's body). As disclosed herein, the inward-facing surface 13 can be understood as being closer to the wearer's body than the outward-facing surface 12. A plurality of thermal insulation elements 15 are coupled to the outward-facing surface 12 of the base fabric, wherein the arrangement and spacing of the plurality of thermal insulation elements such that a portion of the base fabric is not covered, and the base material is able to retain at least a portion of the performance characteristics. As disclosed herein, these insulation elements 15 are specifically developed to provide the insulation material 10 (e.g., fabric) with the following properties: high solar energy absorptivity at wavelengths of 0.3 to 2.5 μm and low thermal emissivity at wavelengths of 5 to 40 μm, enabling the insulation material 10 to retain heat and absorb solar radiation, thereby providing a superior insulation material 10 compared to a base fabric 20 without insulation elements 15.

[0051] In one embodiment, each insulation element 15 has a low thermal emissivity layer 16. In another embodiment, the low thermal emissivity layer 16 of the insulation element 15 is a discontinuous array of foil (e.g., metal foil, such as malleable metals, including but not limited to aluminum, copper, tin, silver, and gold), and in a particular embodiment, aluminum foil. In addition to the low thermal emissivity layer 16, the insulation element 15 includes a high solar absorptivity layer 18 located on the outermost surface of the insulation element 15, for example, above the outward-facing surface of the low thermal emissivity layer 16. For reference, "outward-facing" is exemplarily... Figure 1 The direction indicated by the middle arrow 21. The insulation element 15 may include additional layers, such as a release layer, an adhesive layer, a protective layer for abrasion and oxidation protection, etc. However, the layer thickness must be kept sufficiently small to ensure that the weighted average emissivity of the fabric coupled to the insulation element on the outer surface of the fabric does not rise back to the level of the fabric itself. In an embodiment, the weighted average thermal emissivity of the insulation element 15 is 0.1 to 0.85 (i.e., 10% to 85%), preferably less than 0.7, and most preferably less than 0.5. In an embodiment, the weighted average thermal emissivity of the insulation material 10 to which the insulation element 15 is coupled is less than 0.9 (e.g., 90%), preferably less than 0.7 (e.g., 70%), and most preferably less than 0.5 (e.g., 50%). In an embodiment, the emissivity of the insulation material 10 is about 10% to about 80%, for example, about 15%-65%, about 30%-80%, about 10%-50%, 30%-70%, or about 40%-60%. Therefore, as described herein, a low thermal emissivity layer refers to a layer (e.g., low thermal emissivity layer 16) that imparts a weighted average thermal emissivity of 0.1 to 0.85, preferably less than 0.7, and most preferably less than 0.5 to the insulation element (e.g., insulation element 15), and / or imparts a weighted average thermal emissivity of less than 0.9, preferably less than 0.7, and most preferably less than 0.5 to the insulation material (e.g., insulation material 10).

[0052] In this embodiment, the weighted average solar absorptivity of the insulation element 15 is at least 50% (e.g., 0.5), such as greater than 50%, greater than 55% (e.g., 0.55), greater than 60% (e.g., 0.60), greater than 65% (e.g., 0.65), greater than 70% (e.g., 0.70), greater than 75% (e.g., 0.75), greater than 80% (e.g., 0.80), greater than 85% (e.g., 0.85), or even greater than 90% (e.g., 0.90). In this embodiment, the weighted average solar absorptivity of the insulation material 10 coupled to the insulation element 15 on its outer surface is at least 50%, such as greater than 50%, greater than 55%, greater than 60%, greater than 65%, greater than 70%, greater than 75%, greater than 80%, greater than 85%, or even greater than 90%. As discussed herein, absorptivity refers to the proportion of incident light absorbed; therefore, the value of absorptivity ranges from 0 to 1, where a value of 1 indicates that all incident light is absorbed. Furthermore, as disclosed herein, a high solar absorptivity layer refers to a layer (e.g., high solar absorptivity layer 18) that imparts a weighted average solar absorptivity of at least 0.5, or at least 0.55, or at least 0.6, or at least 0.65, or at least 0.7, or at least 0.75, or at least 0.80, or at least 0.85, or at least 0.90 to the insulation material (e.g., insulation material 10), and / or imparts a weighted average solar absorptivity of at least 0.5, or at least 0.55, or at least 0.6, or at least 0.65, or at least 0.7, or at least 0.75, or at least 0.80, or at least 0.85, or at least 0.90 to the insulation material.

[0053] In various embodiments, the insulating elements 15 are relatively small, such as dots with a diameter of 0.1 to 10 mm, and are arranged discontinuously on the base fabric 20 to avoid excessive interference with the performance characteristics of the base fabric 20. Therefore, in various embodiments, a base fabric 20 (e.g., for personal protective equipment) is disclosed that may employ multiple insulating elements 15 coupled to the base fabric 20 (e.g., the outermost, outward-facing surface of a garment). In one embodiment, the discontinuous pattern of the insulating elements 15 manages body heat by absorbing solar radiation while mitigating radiant heat from or through the outermost surface of the garment back to the environment.

[0054] In one embodiment, a plurality of insulation elements 15 are arranged in a generally discontinuous array on a base fabric 20, wherein some of the base fabric 20 is exposed between adjacent insulation elements 15. In various embodiments, the insulation elements 15 may be arranged in an array of individual elements, while in other embodiments (described in detail below), the insulation elements 15 may be arranged in an interconnected pattern. In some embodiments, the insulation elements 15 may be in the form of a solid shape or a closed loop, such as a circle, square, hexagon, or other shape (including irregular shapes). In other embodiments, the discontinuous pattern of the insulation elements 15 may be in the form of a grid, mesh, or other interconnected pattern.

[0055] Generally, the surface of the base fabric incorporating insulation elements should be exposed to provide sufficient area to deliver the desired base fabric performance characteristics or functions (e.g., stretch, drape, texture, breathability, moisture transfer, gas permeability, and / or wicking). For example, if too little base fabric is exposed, properties such as moisture transfer and / or gas permeability may be compromised, or even disproportionately to the percentage of surface coverage. As used herein, the term "surface coverage area" refers to a measurement taken against a cell, which may be an area containing multiple insulation elements. In one example, a cell is a cell at least 1 inch by 1 inch located at a specific location in a discontinuous array of insulation elements, and does not necessarily correspond to a percentage of the insulation elements covering the entire garment; for example, a 1 inch by 1 inch cell (i.e., a 25.4 mm × 25.4 mm cell), a 2 inch by 2 inch cell (i.e., a 50.8 mm × 50.8 mm cell), a 3 inch by 3 inch cell (i.e., a 76.2 mm × 76.2 mm cell), etc. In one example, a cell could be the entire outer surface of the material on a given garment, measured from seam to seam.

[0056] In various embodiments, the insulating element 15 covers a sufficient area of ​​the outer-facing surface of the base fabric 20 to produce the desired level of insulation (e.g., reducing heat dissipation, or absorbing solar radiation, for example, when exposed to direct or even indirect sunlight, or both). The outer-facing surface of the base fabric 20 may expose a sufficient area to provide or maintain the desired base fabric performance characteristics or functions (e.g., breathability, moisture or air permeability, or wicking). In various embodiments, the insulating element 15 may cover a sufficient surface area of ​​the base fabric 20 to achieve the desired level of insulation; for example, in various embodiments (e.g., in a specific cell, such as a 1-inch × 1-inch cell, i.e., a 25.4 mm × 25.4 mm cell), the surface coverage area of ​​the insulating element 15 may be about 5% to 95%, 10% to 90%, 20% to 80%, 30% to 70%, 40% to 60%, or even about 55%). In a given article or even a part of it, the surface coverage area of ​​the insulation element can be kept constant or vary depending on whether it is inside or across a region of the article.

[0057] In this embodiment, the diameter of a single insulation element is approximately 1 mm, but larger and smaller sizes are also considered. In this embodiment, the diameter of a single insulation element ranges from approximately 0.1 mm to approximately 10.0 mm, for example, approximately 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, or 10.0 mm, or any value or range between the above values. In this embodiment, individual insulation elements within a specific area are spaced approximately 0.1 mm to 10.0 mm apart, for example, approximately 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, or 10.0 mm, or any value or range between these values. As used herein, the diameter is the average distance measured from the center of the insulation element (regardless of its shape), the center being, for example, the geometric center of the insulation element, such as the center of a circle, triangle, square, polygon, or even an irregular shape. Those skilled in the art can determine the geometric center of the shape.

[0058] In an embodiment, the low thermal emissivity layer of a single thermal insulation element comprises or is composed of a metal foil (e.g., aluminum foil) with a thickness ranging from about 5 nm to 100 nm, for example, about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52. 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99 or 100 nm, or any value or subrange within the range considered.

[0059] In embodiments, the high solar absorptivity layer is a polymer or polymer mixture with a thickness ranging from about 0.1 µm to about 10.0 µm, for example, about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, or 10.0 µm, and any numerical value or subrange is also considered. Examples of polymers related to this disclosure may include, but are not limited to: polyethylene, polypropylene, polystyrene, polytetrafluoroethylene, polyisobutylene, polyacrylonitrile, polybutadiene, poly(vinyl chloride), poly(methyl acrylate), poly(methyl methacrylate), polybutadiene, polychloroprene, poly(cis-1,4-isoprene), poly(trans-1,4-isoprene), polyurethane, polyester, polyamide, polyether, polyolefin, polyacrylate, poly(3-hydroxybutyrate) (PHB), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyvalerate] (PHBV), 3-hydroxybutyrate and 3-hydroxyhexanoate (PHBH), polylactic acid (PLA), cellulose, chitin, lacquer, and natural rubber, as well as copolymers or combinations thereof.

[0060] In implementations, the high solar absorptivity layer contains a colorant, such as a colorant that aids in absorbing solar energy. In one example, the colorant is a black colorant. In some examples, the high solar absorptivity layer exists only on the outer surface of the insulation element. In other examples, the high solar absorptivity layer may (at least partially) cover portions of the base fabric that are not coupled to individual insulation elements, for example, as a coating covering both the low thermal emissivity layer and the base fabric.

[0061] In one embodiment, the insulating element is disposed on the outer surface of the bodywear and / or the outermost surface of the base fabric, exposed to the environment. This allows the insulating element to, for example, mitigate radiant heat loss to the environment and absorb solar radiation, while allowing the base fabric to perform its desired function. In some embodiments, the insulating element performs the aforementioned functions without adversely affecting the drape, feel, or other properties of the base fabric. According to various embodiments, the base fabric can be any form of bodywear, body clothing, blankets, tents, rain covers, sleeping bags, or any material or device requiring thermal insulation. As used herein, body clothing includes any item worn on the body, such as, but not limited to: sportswear (e.g., tights, T-shirts, shorts, leggings, arm warmers, headbands, etc.), outerwear (e.g., jackets, trousers, leggings, shirts, gloves, hats, etc.), and footwear.

[0062] In various embodiments, the insulation elements may be disposed on a base fabric having more than one desired property or characteristic. In some embodiments, the base fabric may have other desired properties, such as abrasion resistance, antistatic properties, antimicrobial activity, water repellency, flame retardancy, hydrophilicity, hydrophobicity, windproofness, sun protection, SPF protection, resilience, stain resistance, wrinkle resistance, etc. In other embodiments, the spacing between the insulation elements helps to give the outer-facing surface of the base fabric a desired drape, appearance, and / or texture. Suitable base fabrics may include nylon, polyester, polypropylene, rayon, cotton, spandex, wool, silk, fleece, or blends thereof, or any other material having a desired appearance, feel, weight, thickness, weave, structure, texture, or other desired properties. In various embodiments, allowing a specified percentage of the base fabric to remain uncovered by the multilayer multifunctional insulation elements allows portions of the base fabric to perform their desired function.

[0063] In various embodiments, a single-layer base fabric 20 may be used, comprising an outward-facing surface with insulating elements 15, while in other embodiments, a multi-layer fabric may be used, comprising layers of base fabric 20 coupled to one or more other layers, wherein the base fabric 20 serves as an outer layer having an outward-facing surface with insulating elements 15, for example, covering an insulation layer to form a fluffy material structure. In some embodiments, individual insulating elements 15 are individually coupled (e.g., by adhesive and / or bonding) to the base fabric. In some embodiments, the insulating elements 15 are directly coupled to the base fabric.

[0064] In various embodiments, the insulation element can be permanently coupled to the base fabric in a variety of ways, including but not limited to adhesive bonding, hot pressing, printing, or sewing. In some embodiments, the insulation element can be coupled to the base fabric by frequency welding (e.g., radio frequency welding or ultrasonic welding). In some embodiments, the insulation element can be coupled to the base fabric by a gravure printing process. In some specific non-limiting examples, the gravure printing process can employ an engraving roller immersed in an adhesive bath, the engraving points or lines of which are filled with an adhesive material (e.g., an adhesive for bonding the insulation element to the base fabric). Excess adhesive on the roller can be scraped off with a doctor blade, and then the adhesive is deposited onto the foil as the carrier material (on which a foil containing the insulation material is carried) passes between the engraving roller and the impression roller. The insulation material is disposed on the carrier material as follows: a high solar absorptivity layer is closer to the carrier material than a low thermal emissivity layer, and the adhesive is applied to the surface opposite the carrier material. In various embodiments, the gravure printing process may include direct gravure printing, reverse gravure printing, or differential offset gravure printing. In various embodiments, the weight of the adhesive can be controlled by the solids percentage, gravure volume, pattern depth, and / or the rotational speed of the gravure cylinder. After the adhesive is applied to the foil by the gravure printing process, a substrate (e.g., substrate fabric 20) is laminated onto the adhesive-containing foil. Subsequently, the laminated assembly is extruded and cured in a continuous process flow, after which the carrier material is peeled off, thereby leaving the insulation element 15 on the substrate with a pattern consistent with the pattern engraved on the engraving roller.

[0065] In various implementations, the insulation elements can be applied in a patterned or continuous or discontinuous array. For example, such as Figures 15A to 15HAs shown, the insulation elements can take the form of an array of discrete solid or closed-loop components, fixed to the base fabric in a desired pattern by adhesion or other means. Such configurations have been found to provide insulation while allowing the base fabric to continue to perform its desired properties (e.g., breathability and stretchability). In various embodiments, such discontinuous, discrete, and separate insulation elements can take the form of circles, triangles, squares, pentagons, hexagons, octagons, stars, crosses, crescents, ellipses, or any other suitable shape.

[0066] although Figures 15A to 15H The illustrated embodiments present the insulation elements as separate, discrete units; however, in some alternative embodiments, some or all of the insulation elements may be arranged to interconnect or form larger units, such as stripes, wavy lines, or matrix / grid patterns, or any other pattern capable of partially covering the base fabric. For example, as... Figures 16A to 16F As shown, the thermal insulation elements set on the base fabric can be arranged in the form of various partially interconnected or fully interconnected elements, and the pattern can combine discontinuous elements (such as...). Figures 15A to 15H (as shown), and interconnected geometric patterns (such as) Figures 16A to 16F (As shown). In various embodiments, the pattern of the insulation elements can be symmetrical, ordered, random, and / or asymmetrical. Furthermore, as described below, the pattern of the insulation elements can be strategically positioned on the base fabric to enhance the overall performance of the garment. In various embodiments, the size and / or spacing of the insulation elements can also be adjusted for different areas of the garment to balance the need for enhanced insulation in specific areas while maintaining the functionality of the base fabric.

[0067] In various embodiments, the layout, pattern, and / or coverage ratio of the insulation elements may differ. Of course, the coverage location and ratio can be adjusted depending on the type of garment. In some embodiments, the coverage of the insulation elements can be varied gradually throughout the garment as needed. In various embodiments, the pattern of the insulation elements can be symmetrical, ordered, random, and / or asymmetrical. Furthermore, as described below, the pattern of the insulation elements can be strategically placed on the surface of the base fabric to enhance the performance of the bodywear. In various embodiments, the size of the insulation elements can also be varied to balance the need for enhanced insulation performance with maintaining the functionality of the base fabric.

[0068] In various embodiments, the insulation materials described herein may have superior insulation performance compared to other materials disclosed herein that do not contain insulation materials.

[0069] ASTM G173 provides the solar energy spectrum at the Earth's surface. The total solar power comprises 3.2% in the UV region (UVA and UVB, 0.28–0.38 μm), 53.4% ​​in the visible region (0.38–0.78 μm), and 43.4% in the near-IR region (0.78–3.0 μm). In fact, all solar energy is contained in the wavelength range <2.5 μm (see [reference needed]). Figure 2 ).

[0070] The Planck distribution provides the radiation emitted by the surface of a blackbody at a given absolute temperature (see [reference]). Figure 3 At typical surface temperatures (0-70°C), its emission peaks at approximately 10 μm. Compared to solar radiation, this surface emission is much weaker in intensity but has a much wider range. At nominal skin temperature (35°C), approximately 95% of the energy emitted by a blackbody is at this point. Within the spectral range.

[0071] Thermal emissivity, also known as emissivity, is a measure of an object's ability to emit radiant heat. Emissivity values ​​range from 0 to 1. Metals tend to exhibit low thermal emissivity and high thermal reflectivity, while polymers tend to exhibit high thermal emissivity and low thermal reflectivity.

[0072] For a given object, its measured emissivity depends on the material properties of its surface. In fact, it is common practice to increase the emissivity of metallic objects by painting them black, because paints are polymer coatings, and black colorants generally absorb and emit infrared thermal radiation more than other colorants. Figure 4 The test shown verifies this. A metal plate 401 is placed on a black-coated hot plate 405 to create a high-emissivity surface. A piece of high-emissivity black electrical tape 406 (tape is a polymer film with an adhesive layer) is attached above the metal plate 401. The device is imaged by an infrared (IR) thermal imaging camera 410 mounted on a bracket 412, directly measuring the radiant flux, which is typically proportional to thermal emissivity. The radiant flux is converted to temperature according to the Planck distribution using the camera's built-in software, and the result is typically reported as temperature or apparent temperature. Given the emissivity setting on the IR camera, the thermal emissivity of an object maintained at the same actual temperature will be proportional to its apparent temperature measured by the camera. The hot plate is set to approximately 37°C and a thermal image is obtained. Thermocouples are used to ensure that the temperature of the hot plate (see arrow 415) and the metal plate (see arrow 418) is approximately 37°C (see...). Figure 4 ).

[0073] The results of this test are as follows Figure 5As shown. The figure shows the masked artifact region 502, which is caused by a thermal imaging camera (e.g., ...). Figure 4 This is caused by reflection from the camera 410 on the surface of the metal plate 401 (note) Figure 4 (The camera is positioned directly above the metal plate). The black-painted hot plate 405 (corresponding to box 2, 405a in the figure) shows an apparent temperature of 36.5°C, which matches the actual temperature measured by the thermocouple. In contrast, the metal plate 401 (corresponding to box 1, 401a) shows an apparent temperature of 22.4°C, much lower than the actual temperature measured by the thermocouple, indicating that the metal plate emits less heat than the black-painted area. Therefore, when the outermost surface of an object is metallic, it is expected to exhibit low thermal emissivity, thus retaining more heat rather than dissipating it to the surroundings through radiation. Figure 5 This was further confirmed by placing a small strip of black electrical tape 406 (a thin polymer film with an underlying adhesive layer) on the metal plate 401. The apparent temperature of the black electrical tape (corresponding to box 3, 406a) was 36.8°C, a value consistent with the actual temperature of the metal plate measured using a thermocouple. When the outermost surface of an object is a polymer, the object is expected to exhibit high thermal emissivity, leading to greater radiative heat loss.

[0074] like Figure 6 , 7 As shown in Figures 9 and 10, for the thermal insulation element ( Figure 6 and Figure 7 ) and thermal insulation elements coupled to the fabric surface ( Figure 9 and Figure 10 Tests were conducted to determine its thermal emissivity and solar absorptivity. The solar spectrum (covering the ultraviolet, visible, and near-infrared (UV / Vis / NIR) wavelength range) was used. Spectral measurements were performed using a Laboratory Portable SpectroReflectometer (LPSR) 300 spectrophotometer, generally conforming to ASTM E903. Spectral measurements in the 2.5–40 µm spectral band (covering the mid-infrared (MIR) thermal radiation range) were performed using a Nicoletti S50 Fourier Transform Infrared (FTIR) spectrophotometer equipped with a Pike Upward MID integrating sphere, generally conforming to ASTM E408. The average spot sizes for each measurement were as follows: approximately 7.6 mm × 2 mm rectangular spot for the UV / Vis / NIR band (0.25–2.5 µm); and approximately 8.5 mm × 7.5 mm elliptical spot for the MIR band (2.5–40 µm). For both instruments, it was confirmed that the measurement spot size was sufficiently large relative to the insulation element applied to the fabric surface, such that the measurements represented the average spectral response of the multi-material (i.e., fiber and insulation element) fabric surface. This was verified by considering the deviation between measurements of three samples taken at different locations in each instrument. Measurements of the insulation elements were performed on card stock.

[0075] Reflectance and transmittance were measured. Due to the law of conservation of energy: Therefore, the absorptivity can be calculated by measuring the spectral reflectance and transmittance of an object. According to Kirchhoff's law, spectral emissivity... Equal to spectral absorption rate .for Both fabric and cardboard are opaque in the standard sense (i.e., );therefore, .

[0076] The weighted average thermal emissivity can be calculated as follows:

[0077]

[0078] In the formula, This represents the Planck blackbody distribution at 35℃.

[0079] The weighted average solar absorptivity can be calculated as follows:

[0080]

[0081] In the formula, The solar spectrum is given by ASTM G173.

[0082] Reference Figure 6 , 7Samples 9 and 10, which contain insulation elements (with a thin black polymer layer as the outermost layer covering a thin metal layer), showed lower thermal emissivity than pure black polymer insulation elements. This was an unexpected and surprising result.

[0083] Specifically, Figure 6 The relationship between thermal emissivity and wavelength is depicted for various thermal insulation elements, including silver thermal insulation elements (line 605) (e.g., where the high solar absorptivity layer is free of colorants), the thermal insulation element of this disclosure (line 610), and black polymer thermal insulation elements (line 615) (e.g., pure black polymer thermal insulation elements without metals). Figure 6 In the example shown, the insulation element (line 610) comprises a ferrous metal insulation element. Specifically, a low emissivity layer (e.g.) Figure 1 The low emissivity layer 16 in the middle contains metal, while the high solar absorptivity layer (e.g., Figure 1 The high solar energy absorption layer 18 contains a black colorant within the polymer coating. The weighted average thermal emissivity of the silver insulation element (line 605) is 10.3%, the weighted average thermal emissivity of the black metal insulation element (line 610) is 53.8%, and the weighted average thermal emissivity of the black polymer insulation element (line 615) is 91.3%.

[0084] Figure 7 The above describes the Figure 6 The relationship between solar energy absorptivity and wavelength is discussed for various thermal insulation elements, including silver insulation elements (line 705), insulation elements (line 710), and black polymer insulation elements (line 715). This relates to the previous section on... Figure 6 Similarly, the insulation elements discussed include ferrous metal insulation elements. The weighted average absorptivity of the silver insulation element (line 705) is 17.1%, the weighted average absorptivity of the insulation element (line 710) is 91.5%, and the weighted average thermal emissivity of the black polymer insulation element (line 715) is 93.5%.

[0085] Figure 9 The relationship between thermal emissivity and wavelength is shown for two different fabrics: a black base fabric (line 905), and the same black base fabric on which the insulating element of this disclosure is coupled and covers 55% of the surface (line 910). See reference. Figure 9 The insulation elements include ferrous metal insulation elements, which, in conjunction with the above... Figure 6 and Figure 7 The same applies to the discussion. The weighted average emissivity of the black base fabric (line 905) without insulation elements is 93.5%. The weighted average emissivity of the black base fabric (line 910) with insulation elements coupled thereon is 68.3%.

[0086] Figure 10The above text shows about Figure 9 The relationship between solar energy absorptivity and wavelength is discussed for two different fabrics: a black base fabric (line 1005) and the same black base fabric with the insulating element of this disclosure coupled thereto and covering 55% of the surface (line 1010). The weighted average absorptivity of the black base fabric (line 1005) without the insulating element is 91.9%. The weighted average absorptivity of the black base fabric (line 1010) with the insulating element coupled thereto is 92.0%.

[0087] Thermal resistance was measured using the standard hot plate method and generally conformed to ASTM F-1868 Part A (dry heat transfer) under the following conditions: T 板 =35℃, T 环境 =20℃, relative humidity = 65%, air velocity = 1 m / s. Table 1 shows the test results for six different fabrics (with silver foil laminated on the fabric surface). For each fabric, the thermal resistance increases significantly when the silver foil is located on the outermost surface of the fabric, away from the heat source. For a given fabric, the thermal resistance increases with the increase of the silver foil surface coverage.

[0088] Table 1: Fabrics with silver insulation elements (HME) laminated on the fabric surface show an increase in thermal resistance (clo) when the HME faces upward and away from the heat source.

[0089]

[0090] Table 2: Fabrics with black insulating elements laminated on their surface show an increase in thermal resistance (clo) when the black insulating elements face upwards and away from the heat source. The incident solar energy component on the fabric surface is zero.

[0091]

[0092] The insulating element disclosed herein is located on a fabric, wherein a thin polymer layer (e.g., a thin black polymer layer) is the outermost layer, resulting in improved insulation. This is an unexpected and surprising result. In addition to improving the insulation performance of the base fabric in the absence of incident solar irradiation, further results indicate that the insulation of the fabric is further enhanced when solar irradiation increases the heat load due to absorption and conduction into the insulating material by the black outer layer.

[0093] A thermal model was established ( Figure 11A ) and thermal resistance network ( Figure 11BThe study aimed to determine the influence of material and environmental parameters on the relative importance of thermal emissivity and solar absorptivity in textile insulation. Variable parameters in the model included: thermal emissivity of the fabric surface, solar absorptivity of the fabric surface, thermal resistance of the fabric, air gap between the fabric and skin, ambient temperature, incident solar energy component (i.e., the percentage of solar radiation reaching the clothing surface), air velocity, and activity intensity. Figure 12 Some results of thermal modeling of the heat transferred to the skin relative to the solar component reaching the fabric are shown for three different fabrics: a black base fabric (line 1205), the same black base fabric with 50% silver insulation on the outermost surface (line 1210), and the same black base fabric with 50% black insulation of the present disclosure on the outermost surface (line 1215). When the solar component reaching the fabric is zero, the fabric with silver insulation on the outermost surface retains the most heat. This result is consistent with thermal resistance measurements (see Table 1). However, when the solar component exceeds approximately 3% (as shown by arrow 1220 in the figure), the fabric with black insulation on the outermost surface retains the most heat. Throughout the entire solar component range (from no sunlight to the maximum sunlight), the fabric with black insulation on the outermost surface retains more heat than the black base fabric alone. This is consistent with the versatile nature of the insulation element—low ​​emissivity and high solar absorptivity—and also with the thermal resistance measurements (see Table 2 and...). Figure 12 ).

[0094] Figure 13 A schematic apparatus for conducting experiments is shown to determine the composition of a black base fabric and the thermal insulation element (HME) coupled thereon. Figure 13 Heat capture is achieved by a black base fabric covering 55% of the surface (represented by black dots). The two fabrics are placed side-by-side on top of two layers of fiber insulation (80 gsm each). Thermocouples (TCs) are placed beneath each fabric (TC). a and tc b ), and between the two layers of insulation material (tc c and tc d The hot plate was set to near the core body temperature (37°C), and the entire experimental setup was placed in a cold chamber at 4°C. A Sunlite ENH 250W / MR16 transparent bulb (represented by the sun symbol in the diagram to simulate solar irradiation) was placed approximately 23 cm above the fabric surface.

[0095] Figure 14 To utilize Figure 13The chart shows the data collected by the experimental setup. Before exposure to simulated solar irradiation, even inside the insulation layer, the steady-state temperature beneath the substrate fabric with a thermal management element (HME, also known as an insulating element elsewhere) was higher than that beneath the same substrate fabric without an HME. This result indicates that the fabric with an HME can capture more heat. After turning on the light source to simulate exposure to solar irradiation, even inside the insulation layer, the temperature rise beneath the substrate fabric with an HME was greater than that beneath the same substrate fabric without an HME. Furthermore, after the light source was turned off, even inside the insulation layer, the heat absorbed and conducted to the fabric / insulation laminate beneath the substrate fabric with an HME was retained for a longer time than that beneath the same substrate fabric without an HME. This result is surprising given that the solar absorptivity values ​​of black HME and black fabric are roughly the same. These results reveal that the HME unexpectedly functions as a solar collector, absorbing and conducting more heat into the material and retaining it for longer compared to substrate fabrics with similar solar absorptivity.

[0096] Therefore, in one embodiment, the present invention discusses an insulation material comprising a base fabric having an outer-facing surface and an inner-facing surface, and a plurality of insulation elements coupled to the outer-facing surface of the base fabric. In one example, each of the plurality of insulation elements may comprise a low thermal emissivity layer and a high solar absorptivity layer, wherein the weighted average thermal emissivity of the insulation material is less than 0.8.

[0097] In another embodiment, the body garment includes an insulating material having a base fabric with an outward-facing surface and an inward-facing surface, and a plurality of insulating elements coupled to the outward-facing surface of the base fabric. In this example, each of the plurality of insulating elements may include a low thermal emissivity layer and a high solar absorptivity layer, wherein the weighted average thermal emissivity of the insulating material is less than 0.8.

[0098] In yet another embodiment, a method of manufacturing an insulation material includes selecting a base fabric having an outer-facing surface and an inner-facing surface, and coupling one or more insulation elements to the outer-facing surface of the base fabric. In this example, each of the more than one insulation element may include a low thermal emissivity layer and a high solar energy absorptivity layer.

[0099] While the above embodiments generally disclose a structure having a base material and a plurality of insulating elements disposed on the outer-facing surface of the base material, in other embodiments, layers of more than one insulating element may be disposed on other surfaces of the insulating material or in other locations inside the garment containing these insulating elements.

[0100] In some implementations, the insulation material may be placed below the solar transmission material.

[0101] In some embodiments, the insulating material may be disposed below the solar transmission material and the solar transmission insulation layer. This embodiment (referred to as a fluffy material structure) may be employed, and aspects of other embodiments described herein may also be used to achieve enhanced solar thermal gain.

[0102] Loose material constructions are those specifically designed for insulation applications. They are thicker than typical woven or knitted fabrics and can consist of more than one layer of material. For example, a typical loose material construction commonly used in outerwear typically consists of a lining fabric, an insulation layer, and a shell fabric. Another example is fleece, which consists of floats and bonded yarns, where the floats are napped to create a pile surface on one or both sides of the "base" or underlay knitted fabric.

[0103] For the bulky material structures typically used in outerwear, due to their thickness and high air content, the heat gained by the wearer through absorbing solar radiation on the surface of the outer fabric may be limited, as the high air content of the insulation layer prevents heat conduction from the outer surface to the body. In fact, while solar energy absorbed by the outer fabric is conducted and radiated inwards towards the body, it is also dissipated into the environment through conduction, convection, and radiation. The balance of these two opposing heat transfer directions determines the magnitude of the solar thermal gain.

[0104] Therefore, in the various embodiments described herein, a fluffy material structure is provided that unexpectedly absorbs solar radiation significantly better than typical, ordinary fluffy fabric structures, thereby generating a higher solar thermal gain and providing more heat to the wearer. This higher solar thermal gain is achieved through a fluffy material structure comprising layers, wherein the lower layer absorbs solar radiation more strongly than a typical lower layer, while the upper layer has a certain degree of solar irradiance transmittance (…). ).

[0105] In such Figure 17 In the illustrated outerwear / clothing embodiment, a suitable structure includes a solar transmission shell fabric 1702, a solar transmission heat insulation layer 1704, and a solar absorption lining fabric 1706.

[0106] For a given shell fabric and insulation layer with a certain solar transmittance, replacing the lining fabric with a lining fabric having a higher solar absorptivity can increase solar thermal gain. Suitable implementations include lining fabrics with a discontinuous array of insulation elements (e.g., insulation elements as described above) coupled thereon, exhibiting high solar absorptivity (α) at ​​wavelengths of 0.3 to 2.5 μm and low thermal emissivity at wavelengths of 5 to 40 μm, allowing the lining fabric to absorb solar radiation and retain heat, thus providing a warmer insulation material compared to the same base fabric without the discontinuous array of insulation elements.

[0107] The implementation described in this article provides a net thermal benefit known as enhanced solar thermal gain (ESHG).

[0108] In one embodiment, the insulation element is positioned on the outermost surface of the lining fabric (facing away from the wearer's body when worn). In an alternative embodiment, the insulation element is positioned on the innermost surface of the lining fabric (facing towards the wearer's body when worn).

[0109] Figure 18 This is a detailed view of the solar transmission housing fabric 1702. As shown, the solar transmission housing fabric 1702 has an outward-facing surface 1707 (as previously described with respect to other embodiments), which forms... Figure 17 The outermost (outer-facing) surface of the outer garment is shown. The term "outer-facing" is exemplarily the direction indicated by arrow 21. Furthermore, the solar-transmitting housing fabric 1702 has an inner-facing surface 1708 configured to contact the solar-transmitting heat-insulating layer 1704 (see [link]). Figure 17 ).

[0110] Solar-transmitting fabric 1702 can consist of one or more layers, provided that such one or more layers can transmit (allow) sufficient solar radiation. The transmittance of solar-transmitting fabric 1702 must be greater than 0; the higher the transmittance, the greater the solar thermal gain near the human body. At 0°C and on a moderately sunny day (600 W / m²), 2 Under these conditions, the transmittance of the shell fabric covering 60 gsm polyester sheet insulation (with an estimated solar transmittance of about 50%) should be at least 20%. At -20°C, the shell transmittance should be at least 40%. Therefore, in some embodiments herein, a suitable range of solar radiation transmittance for the solar transmittance fabric should be at least 20% to 40%.

[0111] In an implementation, the solar-transmitting fabric may be composed of one or more of the following materials: nylon, polyester, polypropylene, rayon, cotton, spandex, wool, silk, fleece, or blends thereof, or any other material having a desired appearance, feel, weight, thickness, structure, or texture, and also having sufficient solar transmission capacity.

[0112] The solar transmission insulation layer 1704 may be composed of one or more of the following materials: polyester, nylon, cotton, silk, wool, down, imitation down / synthetic down, milkweed fiber, or blends thereof, or any other material capable of trapping air. It may be in sheet form, feather form, loose fiber form, nonwoven form, partitioned form, or any other form that allows for the formation of a fluffy, air-trapping layer, restricts material displacement, and simultaneously provides sufficient solar transmission capacity. For a typical sheet insulation density of 40 to 200 gsm, a suitable thickness range for the solar transmission insulation layer is less than or equal to 20 mm, or for an insulation density greater than 200 gsm (e.g., 300 gsm), a suitable thickness range is less than or equal to greater than 35 mm. Therefore, in some embodiments herein, the suitable thickness range for the solar transmission insulation layer is less than or equal to 20 to 35 mm.

[0113] In various implementations, the material and thickness of the solar transmission insulation layer 1704 can be selected to maximize its transmittance to solar radiation while maintaining sufficient insulation. This can be achieved by using a translucent or light-colored insulation layer. Using a translucent or light-colored (e.g., white) insulation layer to allow maximum transmission through the insulation layer provides insulation advantages. The use of any pigment or dye (especially dark pigments such as black) in the insulation layer, whether naturally occurring or intentionally added, may reduce the solar thermal gain beneath the lining material.

[0114] Figure 19 This is a detailed drawing of the solar-absorbing lining fabric 1706. As shown, the solar-absorbing lining fabric 1706 includes a lining fabric 1710 having an outward-facing surface 1712 and an inward-facing surface 1713. The outward-facing surface 1712 is configured to face the external environment when worn and is configured to contact the solar-transmitting insulating layer 1704. The inward-facing surface 1713 is configured to face the wearer as the innermost surface of the garment when worn. The solar-absorbing lining fabric 1706 also includes an insulating element 15 as described above, which includes a low thermal emissivity layer 16 and a high solar absorptivity layer 18.

[0115] Although Figure 19 The insulation element is shown located on the outer-facing surface 1712 of the lining fabric, but it should be understood that the insulation element may also be located on the inner-facing surface 1713 of the lining fabric.

[0116] In this embodiment, the lining fabric 1710 may be composed of one or more of the following materials: nylon, polyester, polypropylene, rayon, cotton, spandex, wool, silk, fleece, or blends thereof, or any other material having the desired appearance, feel, weight, thickness, structure, or texture. Using a black or other dark-colored lining fabric can provide further insulation benefits compared to using a white lining fabric.

[0117] To test the above design, an experimental setup was designed and constructed. This setup included a thermocouple atop a flat, white sample stage, with a sun lamp (bulb height to sample stage surface = 39 cm) mounted above the stage. The sun lamp was a Sunlite projector from Sunshine Lighting (model: ENH 250W / MR16 / 120V / CL / GY5.3). Three different materials were used: (A) a black woven fabric (0.08 mm thick, 78 gsm, 90% polyester, 10% elastane); (B) the same black woven fabric, but with a high-α insulation element (0.1 mm thick, 87 gsm) applied to its surface in a discrete pattern, covering 50% of the surface area; and (C) 100 gsm polyester sheet insulation material (approximately 15 mm thick).

[0118] The solar transmittance through each individual material was estimated separately by placing a solar power meter (TES Electrical Electronic Corp. TES-132) under each material. The solar transmittance was: (A) 480 W / m 2 (B) 220W / m 2 (Insulation element facing the lamp); and (C) 560W / m 2 The solar power was set to 1100W / m when no material was placed between the solar light and the solar power meter. 2 Therefore, the insulation layer transmits the most solar radiation, while the black woven fabric with high-alpha insulation elements facing outwards absorbs the most solar radiation.

[0119] Three materials (A, B, and C) were stacked to construct four different fluffy material structures, described in the following order from the innermost (closest to the skin) to the outermost (closest to the environment): (1) B (with an inward-facing high-α insulation element) - CA; (2) B (with an outward-facing high-α insulation element) - CA; (3) ACB (with an outward-facing high-α insulation element); and (4) ACB (with an inward-facing high-α insulation element). The four different fluffy material structures (e.g.) Figure 20A-20DThe sample (as shown) is placed on the sample stage such that the distance from the bulb to the surface is approximately 24 cm.

[0120] After turning on the solar lights, measure the temperature change under the fluffy material structure over time for at least 10 minutes until thermal equilibrium with room temperature (approximately 25°C) is reached. Record the highest steady-state temperature and display it in Table 3.

[0121] Table 3: Solar Irradiance (1100W / m²) 2 The highest steady-state temperature reached on the back of four different fluffy material structures.

[0122]

[0123] The highest solar thermal gain (82°C) was achieved when a material with an outward-facing high-α insulation element was used as the innermost layer (or lining). This was unexpected, as solar energy must first penetrate through the black shell fabric and the 15 mm thick insulation layer to reach the solar absorption lining.

[0124] When a material with high α insulation elements facing outwards is selected as the outermost layer or shell fabric, the second highest solar thermal gain (77°C) is obtained.

[0125] Data shows that high-α insulation elements with only 50% surface coverage are surprisingly effective at transforming standard solar-absorbing material (black woven fabric) into a material that absorbs more solar radiation. When the insulation element faces outwards, the highest temperature for the same set of materials stacked in the same order is higher than when the element faces inwards: 82°C vs. 71°C, and 77°C vs. 64°C. Solar transmittance data (showing how the high-α insulation element increases the solar transmittance of the black woven fabric from 480 W / m²) is also presented. 2 Reduced to 220W / m 2 This further confirms the effectiveness of thermal insulation elements in enhancing solar energy absorption.

[0126] As shown in the various specific embodiments, the solar thermal gain increases with the increase of the solar absorptivity of the liner layer and the solar transmittance of the shell and insulation layers. Replacing the liner with a typical black woven fabric and then with a woven fabric featuring high-α insulation elements facing outwards can increase the steady-state maximum temperature under solar radiation by at least 20°C. Conversely, increasing the thickness and weight of the insulation layer from 40 to 60 and then to 100 gsm will reduce the solar transmittance, but the effect on the steady-state maximum temperature under solar radiation is zero or negligible. These results are shown in Table 4.

[0127] Table 4: Influence of solar transmittance of lining and insulation layer on steady-state maximum temperature of three-layer laminated structure under solar irradiation

[0128]

[0129] To further illustrate aspects of the embodiments described herein, a standard outer garment structure was tested, consisting of a black polyester woven lining, a black polyester woven shell fabric, and 60 or 100 gsm polyester sheet insulation. Table 5 shows the results at 1100 W / m 2 Under solar irradiance, their steady-state maximum temperatures are 62℃ and 60℃, respectively.

[0130] When the solar transmittance is 420W / m 2 The standard black casing fabric has been replaced with one that has a solar transmittance of 860 W / m. 2 When the shell fabric is used, the steady-state maximum temperature under solar irradiation increases by 17 to 18°C.

[0131] Similarly, when the standard black lining was replaced with a lining fabric featuring high-α insulation elements with 50% surface coverage, the steady-state maximum temperature under solar irradiation increased by 15 to 16°C.

[0132] Surprisingly, when the standard black lining and shell fabric were simultaneously replaced with a high-solar-absorbance lining and a high-solar-transmittance shell fabric, respectively, the steady-state maximum temperature under solar irradiation increased by 39 to 41°C. These figures are more than double the increase achieved by replacing only one layer, indicating a synergistic effect between increasing solar transmittance through the shell fabric and increasing solar absorptivity through the lining fabric. The solar thermal gain of this bulky material structure was enhanced in an unexpected way, and this enhancement was not merely a simple linear summation of the increased solar transmittance of the shell fabric and the increased solar absorptivity of the lining fabric.

[0133] Table 5: Steady-state maximum temperature of standard outer casing structure under solar irradiation, and the effect of improving the solar transmittance of the shell and the solar absorptivity of the lining.

[0134]

[0135] To further test the embodiments described herein, an experimental setup was assembled, including a thermoelectric plate [ThermoElectric Cooling America Corp (TECA), AHP-1200CPV high-capacity cooling / heating plate ECN003] equipped with an RTD probe (TECA, 100 ohms, 6 inches × 1 / 8 inch diameter); a solar simulator (Sci-Sun-150); and a heat flux sensor (FluxTeq PHFS-01) connected to a data logger (GRAPHTEC GL240). Two different bulky material structures were prepared by layering a polyester woven shell fabric with a polyester woven lining and using the same 60 gsm polyester sheet insulation material (approximately 11.5 mm thick): (1) a standard outer garment structure; and (2) an enhanced solar thermal gain (ESHG) outer garment structure. The standard structure consisted of a black shell (70 gsm, 0.1 mm thick) and a black lining (70 gsm, 0.08 mm thick). The ESHG structure consists of a gray translucent shell (36 gsm, 0.04 mm thick) and a light gray lining with high solar energy absorption (40 gsm, 0.07 mm thick; thermal insulation elements with high solar energy absorption and 50% surface coverage).

[0136] The experiment was conducted in an environmental chamber at 0°C, where the thermoelectric plate was set to maintain a temperature of 33°C to simulate human skin temperature, and the intensity of the solar simulator on the surface of the material laminate was set to 1000 W / m. 2 Each layer of the material structure is at least 12 inches square to minimize heat loss at the edges. A 1-inch square heat flux sensor is centrally positioned on top of a thermoelectric plate, and the sample stack is centrally positioned on top of the heat flux sensor on the plate. Thermally conductive tape is used over the heat flux sensor to ensure thermal contact with the lining fabric. Table 6 shows the results for these two fluffy material structures under two different wind speed conditions.

[0137] Table 6: At 0℃ and under solar radiation (1000W / m 2 Under these conditions, the steady-state skin heat flux through a standard structure and an enhanced solar thermal gain fluffy material structure.

[0138]

[0139] Steady-state skin heat flux measures the amount of heat flowing to the skin. The Enhanced Solar Heat Gain (ESHG) bulky material structure exhibits a higher skin heat flux than the standard structure, regardless of whether there is wind (4 m / s) or no wind (<0.5 m / s). In fact, at a wind speed of 4 m / s, the standard structure has a negative skin heat flux; this means that under these steady-state conditions, heat is continuously being lost from the skin. In other words, a standard black jacket using 60 gsm sheet insulation will still experience heat loss even in sunlight at 0°C. On the other hand, the ESHG structure achieves heat gain under the same conditions at 0°C.

[0140] As sunlight intensity decreases, solar thermal gain also decreases. When solar thermal gain decreases sufficiently, skin heat flux turns from positive to negative. This solar irradiance value can be estimated using thermal modeling for a given material property and environmental conditions. Below this value, a given bulky material structure (e.g., a jacket) begins to lose heat under given conditions.

[0141] The relationship between skin heat flux and solar irradiance is approximately linear. Using the material properties shown in Table 7, skin heat flux under different solar irradiance conditions was modeled under the environmental conditions tested using the aforementioned ESHG material structure. Solar irradiance was estimated when skin heat flux changed from net cooling to net heating. These results are shown in Table 8.

[0142] Table 7: Performance of the middle layer of the enhanced solar thermal gain fluffy material structure

[0143]

[0144] Table 8: Estimated solar irradiance at 0°C. Below this value, the steady-state skin heat flux of the fluffy material structure with enhanced solar thermal gain turns negative.

[0145]

[0146] The results showed that, under windy conditions, more sunlight is required to maintain net positive skin heat flux, which is consistent with expectations.

[0147] Using the same thermal modeling method, the minimum shell transmittance for a positive skin heat flux can be estimated. Table 9 lists the results for three different solar intensities at two different temperatures under windless conditions (<0.5 m / s).

[0148] Table 9: Estimated shell transmittance values; for values ​​higher than this, the steady-state skin heat flux of the enhanced solar thermal gain fluffy material structure is positive.

[0149]

[0150] When solar irradiance is greater than 300W / m 2 Furthermore, at 0°C, a shell fabric with a transmittance of at least 0.56 allows sufficient solar energy to be transmitted into the ESHG material structure, providing a net positive heat flux to the skin. The shell fabric of the ESHG material structure described in the aforementioned example has a solar transmittance of 0.51, which is [not specified in the original text]. 2 Tests were conducted under the conditions of [condition missing], confirming that the structure provides a net positive heat flux to the skin. The modeling results shown in Table 9 are consistent with the test results. The model also indicates that the above-mentioned ESHG structure can operate at 0°C and with low solar energy intensity (600 W / m²). 2 (and at -20°C and a solar intensity of at least 600 W / m) 2 Under the above conditions, a net positive heat flux can be provided to the skin.

[0151] Additional experiments were conducted to evaluate the impact of the selected lining fabric on the layer material structure.

[0152] A multi-layered material structure was designed, allowing sufficient sunlight to pass through the outer layer and be absorbed by the innermost layer (closest to the skin), creating a localized solar thermal effect. Each material structure consists of an outermost shell fabric, a middle insulation layer, and an innermost (skin-side) lining fabric. Four different material structures were assembled by stacking commercially available synthetic woven fabrics, using the same polyester sheet insulation material (60 g / m²). 2 (The thickness is 11.5 mm). All three structures use a semi-transparent gray fabric (36 g / m²). 2 The shell is 0.04 mm thick and uses one of the following three linings: white fabric (70 g / m²). 2 Thickness 0.08 mm), black fabric (70 g / m²) 2 The fabric is light gray (40g / m²) with a thickness of 0.08 mm and a printed pattern of thermal insulation elements covering 50% of the surface. 2 The insulation element is multi-layered and engineered to combine high solar energy absorption with low thermal emissivity. This engineered lining enhances solar energy absorption while minimizing re-radiative heat loss. A fourth material structure was manufactured to represent the standard outer garment, employing a more opaque black shell fabric (70 g / m²). 2 (with a thickness of 0.1 mm), and uses the same black lining fabric and sheet insulation material described above.

[0153] At 1000W / m 2 The thermal properties of the material structure were tested under solar irradiation. Figure 21 The experimental setup and the various fabric layers are shown.

[0154] Figure 22 Four different layered material structures were shown exposed at 0°C to 1000 W / m 2 Skin heat flux measured under solar irradiation. Although all samples had similar thermal resistance in both conduction and convection (mainly due to the sheet-like insulation), the sample with the more opaque black shell exhibited the lowest skin heat flux (71 W / m²). 2 In other words, due to the low solar transmittance of its shell fabric ( This material structure also provides the lowest solar thermal gain. For the use of a semi-transparent shell ( The material structure of the white lining (with low solar energy absorption) performed the worst (net heat flux to the skin was 118 W / m²). 2 ), followed by a black lining (144W / m 2 ) and patterned lining (220W / m 2 ).

[0155] The material structure of the shell fabric with lower opacity has the lowest solar thermal gain because more solar energy is blocked at the outermost surface. Heat absorbed at this location can easily dissipate into the cold environment. Fabrics with layered patterned linings have a higher solar thermal gain due to the combination of a solar-transmitting shell and insulation layer, along with an engineered lining fabric with higher solar absorptivity. Therefore, solar energy is absorbed and trapped closer to the skin, resulting in a nearly three-fold increase in net skin heat flux. These results may seem counterintuitive, as black is generally considered the most heat-absorbing color in sunlight, so a garment with a black shell fabric should be expected to be hotter in the sun. However, the important concept illustrated here is that the depth of solar absorption is crucial. By designing the material structure to enhance the transmittance of sunlight through the outer insulation layer, solar energy is absorbed closer to the body, effectively increasing the solar thermal gain.

[0156] While certain specific embodiments have been illustrated and described herein, those skilled in the art will understand that various alternative and / or equivalent embodiments or calculated implementations may be used to achieve the same purpose without departing from the scope of this document. It will be readily apparent to those skilled in the art that the embodiments described herein can be implemented in a wide variety of ways. This application is intended to cover any adaptations or variations made to the embodiments discussed herein. Therefore, it is clear that the embodiments are intended to be limited only by the claims and their equivalents.

Claims

1. A garment comprising: A solar-transmitting shell fabric having an outermost outward-facing surface and an inward-facing surface, the outward-facing surface being configured to face the environment when worn; A lining fabric having an outer-facing surface and an innermost inner-facing surface, the outer-facing surface being configured to face the environment when worn, and the inner-facing surface being configured to face the wearer when worn. The lining fabric also includes a plurality of insulating elements coupled to the lining fabric, each of the plurality of insulating elements having: Low thermal emissivity layer; and High solar energy absorption layer; as well as A solar transmission heat insulation layer is located between the inward-facing surface of the solar transmission shell fabric and the outward-facing surface of the lining fabric.

2. The garment according to claim 1, wherein, The plurality of thermal insulation elements are located on the outer-facing surface of the lining fabric.

3. The garment according to claim 1, wherein, The plurality of thermal insulation elements are located on the innermost, inward-facing surface of the lining fabric.

4. The garment according to claim 1, wherein, The solar transmission shell fabric has a solar radiation transmittance of at least 20-40%.

5. The garment according to claim 1, wherein, The thickness of the solar transmission insulation layer is less than or equal to 20-35 mm.

6. The garment according to claim 5, wherein, The density of the solar transmission insulation layer is 40-300 gsm.

7. The garment according to claim 1, wherein, The weighted average thermal emissivity of the lining fabric is less than 0.

8.

8. The garment according to claim 1, wherein, The low thermal emissivity layer is a metal foil.

9. The garment according to claim 8, wherein, The metal foil is aluminum.

10. The garment according to claim 1, wherein, The thickness of the low thermal emissivity layer is 5 nm to 100 nm.

11. The garment according to claim 10, wherein, The thickness of the low thermal emissivity layer is 30-50 nm.

12. The garment according to claim 1, wherein, The thickness of the high solar energy absorption layer is from 0.1 µm to 10.0 µm.

13. The garment according to claim 12, wherein, The thickness of the high solar energy absorption layer is 1.0-1.4 µm.

14. The garment according to claim 1, wherein, The high solar energy absorption layer includes a polymer capping layer.

15. The garment according to claim 1, wherein, The high solar energy absorption layer contains a colorant.

16. The garment according to claim 15, wherein, The colorant is a black colorant.

17. The garment according to claim 1, wherein, The solar transmission insulation layer contains a translucent or white insulation material.

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