Self-regulating thermal and cooling fabric

Abstract

The application provides a self-adjusting warm-keeping and cooling fabric, which comprises a water-absorbing fabric layer and an infrared high-reflection porous hydrophobic layer arranged on the inner side of the water-absorbing fabric layer, the infrared emissivity of the water-absorbing fabric layer is lower than 30% in a dry state and higher than 80% in a wet state, the inside of the pores of the infrared high-reflection porous hydrophobic layer is a hydrophilic structure, and the infrared high-reflection porous hydrophobic layer is close to the skin side, forming a one-way wetness guiding structure from inside to outside. The application forms a one-way wetness guiding temperature adjusting structure through the outer hydrophilic fabric layer with low infrared emissivity and the inner infrared high-reflection porous hydrophobic layer, which can inhibit the infrared radiation heat dissipation of the fabric in a dry state, realizes the warm-keeping function, when the fabric is in a wet state due to the sweating of the human body, the whole fabric is converted into high infrared emission characteristics, thereby improving the heat dissipation effect, and finally realizing the automatic adjustment of the warm-keeping and cooling. The application has the advantages of simple preparation method, novel structure, convenient use and significant economic value.

Description

Technical Field

[0001] This invention relates to the field of functional fabric technology, and in particular to a self-regulating heat-insulating and cooling fabric. Background Technology

[0002] With the development of textile research and technology and people's increasing demand for quality of life, fabrics are gradually evolving towards multifunctionality and intelligence. Among them, thermal comfort fabrics enable clothing to maintain warmth in winter and coolness in summer. Currently, intelligent temperature-regulating fabrics are being gradually applied in clothing manufacturing, showing significant effects in improving thermal comfort and wearability. However, with existing technology, most intelligent temperature-regulating fabrics achieve their temperature regulation function through electric heating or fan cooling. The disadvantages of such fabrics include energy consumption, inconvenience in wearing, and reduced comfort.

[0003] Intelligent temperature-regulating fabrics have attracted much attention from researchers in recent years. Current methods mainly utilize thermal radiation regulation, thermal convection regulation, and thermal conduction regulation to achieve intelligent temperature control. Patent CN113907583A discloses a lightweight structural thermal insulation material, a heat pack, and its manufacturing method, comprising an outer layer, a middle layer, and an inner layer. The outer layer is a low infrared emissivity layer, the middle layer is a thermally conductive insulation layer, and the inner layer is an infrared blocking layer. This method constructs a structural thermal insulation material with an infrared low emissivity-thermal conduction blocking-infrared absorption blocking mode, simultaneously blocking heat conduction and thermal radiation dissipation, thus improving the material's thermal insulation performance. Patent CN113561578A discloses a radiation-cooling fabric and its design method, comprising a layered first layer structure and a second layer structure. The first layer structure is a reflective film, and the second layer structure is a fabric layer, capable of reflecting visible-near infrared wavelengths and emitting mid-infrared wavelengths. This method achieves thermal insulation and cooling functions by emitting sunlight and mid-infrared rays. However, none of the above methods can simultaneously achieve both thermal insulation and cooling effects.

[0004] Patent CN110565176A discloses a temperature-regulating fabric based on carbon nanotubes and its preparation method, comprising: an inner structural layer including a carbon nanotube layer and a metal layer coated on the carbon nanotube layer, wherein the infrared emissivity of the metal layer is lower than that of the carbon nanotube layer; and an outer structural layer covering at least a first surface and a second surface of the inner structural layer, wherein the first and second surfaces are arranged opposite to each other in the thickness direction of the inner structural layer, and the outer structural layer has a porous structure that allows infrared light to pass through. This method utilizes the difference in infrared emissivity between the two directions of the inner structural layer to automatically adjust the temperature according to changes in ambient temperature, achieving both heat preservation and cooling effects. While this method can achieve both heat preservation and cooling effects, it requires changing the surface of the fabric to achieve different effects, which is inconvenient for wearable fabrics.

[0005] In view of this, it is necessary to design an improved self-regulating heat-insulating and cooling fabric and its application to solve the above problems. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the present invention aims to provide a self-regulating heat-insulating and cooling fabric. Through a hydrophilic outer layer with low infrared emissivity and a porous hydrophobic inner layer with high infrared reflectivity, a one-way moisture-wicking and temperature-regulating structure is formed. This structure can suppress the infrared radiation heat dissipation of the fabric in a dry state, thereby achieving the heat-insulating function. When the human body sweats and the fabric becomes wet, the entire fabric is converted into a high infrared-emissive material, thereby improving the heat dissipation effect and ultimately achieving automatic regulation of heat preservation and cooling.

[0007] To achieve the above-mentioned objectives, the present invention provides a self-regulating heat-insulating and cooling fabric, comprising a water-absorbing fabric layer and an infrared high-reflectivity porous hydrophobic layer disposed on its inner side. The water-absorbing fabric layer has an infrared emissivity of less than 30% in a dry state and an infrared emissivity of more than 80% in a wet state. The pores of the infrared high-reflectivity porous hydrophobic layer have a hydrophilic structure inside. The infrared high-reflectivity porous hydrophobic layer near the skin forms a one-way moisture-wicking structure from the inside out.

[0008] Preferably, the infrared emissivity of the absorbent fabric layer in a wet state is higher than 90%, more preferably higher than 95%; and the infrared emissivity in a dry state is lower than 20%, more preferably lower than 10%.

[0009] Preferably, the difference in water contact angle between the absorbent fabric layer and the infrared high-reflectivity porous hydrophobic layer is greater than 40°, more preferably greater than 50°, and even more preferably greater than 90°.

[0010] Preferably, the absorbent fabric layer is a polyamide fiber fabric, a hydrophilic polyethylene fiber fabric, or a blend of both; the hydrophilic polyethylene fiber fabric is a polyethylene fiber fabric with an irregular cross section or a polyethylene fiber fabric that has been hydrophilically coated or grafted; the irregular cross section is a peanut-shaped or cross-shaped cross section.

[0011] Preferably, the thickness of the infrared high reflectivity porous hydrophobic layer is 200-400 μm, the pore size is 0.1-2 mm, and the pore spacing is 3-20 mm.

[0012] Preferably, the pores of the infrared high reflectivity porous hydrophobic layer are filled with a hydrophilic material. The hydrophilic material is pre-filled into the pores of the infrared high reflectivity porous hydrophobic layer, or the infrared high reflectivity porous hydrophobic layer is first coated on the inner side of the absorbent fabric layer, and then the hydrophilic fibers of the absorbent fabric layer are pressed to fill the pores of the infrared high reflectivity porous hydrophobic layer.

[0013] Preferably, the infrared high-reflectivity porous hydrophobic layer is a porous metal film; the porous metal film is preferably a metal film formed from one or more of gold, silver, and aluminum.

[0014] Preferably, the porous metal membrane is adhered to the inner side of the absorbent fabric layer by means of coating and pressing, and the hydrophilic fibers are pressed and filled into the pores of the porous metal membrane during the pressing process.

[0015] Preferably, the inner side of the absorbent fabric layer is brushed to form hydrophilic short fibers, so that the hydrophilic short fibers are pressed into the pores of the porous metal membrane.

[0016] The application of any one of the above self-regulating warming and cooling fabrics, wherein the self-regulating warming and cooling fabric is used in the preparation of close-fitting warming and cooling clothing, wherein when the self-regulating warming and cooling fabric is in a dry state, the infrared blocking effect of the infrared high reflectivity porous hydrophobic layer imparts a warming effect to the clothing, and when human sweat soaks into the self-regulating warming and cooling fabric, the self-regulating warming and cooling fabric has high infrared emission to achieve infrared radiation heat dissipation and cooling function.

[0017] The beneficial effects of this invention are:

[0018] 1. The self-regulating heat-insulating and cooling fabric provided by this invention forms a one-way moisture-wicking and temperature-regulating structure through a hydrophilic outer layer with low infrared emissivity and an infrared-high reflectivity porous hydrophobic inner layer. This design prevents heat loss via infrared radiation when the fabric is dry, thanks to the high infrared reflectivity of the inner layer, thus achieving a heat-insulating effect. When the body sweats due to increased temperature from heat retention, the one-way moisture-wicking structure allows sweat to be quickly guided from the pores of the infrared-high reflectivity porous hydrophobic layer to the outer absorbent fabric layer. This wets both the absorbent fabric layer and the inner layer, transforming the entire fabric into an infrared-high emitting material, thereby dissipating heat through infrared emission and achieving a cooling effect, preventing overheating and discomfort. Furthermore, the rapid evaporation of sweat due to the one-way moisture-wicking structure helps to remove heat and maintain the fabric's dryness and comfort.

[0019] 2. This invention utilizes the difference in hygroscopicity between the inner and outer layers, as well as the porous structure of the inner layer, to allow sweat to rapidly permeate and be transported outward under pressure differential. By filling the pores of the inner layer with a hydrophilic material, it facilitates both the transport and drainage of sweat from the pores and the wetting of sweat within the pores, thereby endowing the inner layer with high infrared emissivity and improving infrared radiation heat dissipation. This invention features a simple preparation method, novel structure, and ease of use, making it suitable for large-scale manufacturing and application, and demonstrating significant economic value. Attached Figure Description

[0020] Figure 1 A schematic diagram of the structure of the self-regulating heat-insulating and cooling fabric provided by the present invention.

[0021] Figure 2 Infrared reflectance spectra of the self-regulating heat-insulating and cooling fabric prepared in Example 2 under dry and wet conditions.

[0022] Figure 3 The temperature change curves over time for the self-regulating heat-insulating and cooling fabric (sample) and cotton fabric prepared in Example 2.

[0023] Figure 4 The temperature change curves over time for the self-regulating heat-insulating and cooling fabric (sample) and cotton fabric prepared in Example 2. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to specific embodiments.

[0025] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the solution of the present invention are shown in the specific embodiments, while other details that are not closely related to the present invention are omitted.

[0026] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0027] Please see Figure 1As shown, this invention provides a self-regulating heat-insulating and cooling fabric, comprising an absorbent fabric layer and an infrared-high reflective porous hydrophobic layer disposed on its inner side. The absorbent fabric layer has an infrared emissivity of less than 30% in a dry state and an infrared emissivity of more than 80% in a wet state. The pores of the infrared-high reflective porous hydrophobic layer have a hydrophilic structure, and the side of the infrared-high reflective porous hydrophobic layer close to the skin forms a one-way moisture-wicking structure from the inside out. With this configuration, when the fabric is dry, the high infrared reflectivity of the inner infrared-high reflective porous hydrophobic layer prevents heat loss through infrared radiation, thus achieving a heat-insulating effect. When the body temperature rises and sweats due to heat preservation, the one-way moisture-wicking structure of the inner hydrophobic layer and the outer hydrophilic layer allows sweat to be quickly guided from the pores of the infrared-high reflective porous hydrophobic layer to the outer absorbent fabric layer, so that both the absorbent fabric layer and the pores of the inner layer are wetted. At this time, the entire fabric transforms into an infrared-high emissive characteristic, thereby dissipating heat through infrared emission and achieving a cooling effect, preventing excessive heat preservation and discomfort caused by overheating. In addition, sweat evaporates quickly due to the one-way moisture-wicking structure, which can remove heat on the one hand and keep the fabric dry and comfortable on the other.

[0028] Preferably, the infrared emissivity of the absorbent fabric layer in a wet state is higher than 90%, more preferably higher than 95%; and the infrared emissivity in a dry state is lower than 20%, preferably lower than 10%. For example, the absorbent fabric layer is a polyamide fiber fabric, a hydrophilic polyethylene fiber fabric, or a blend of both; the hydrophilic polyethylene fiber fabric is a polyethylene fiber fabric with an irregular cross section or a polyethylene fiber fabric that has been hydrophilically coated or grafted; the irregular cross section is a peanut-shaped or cross-shaped cross section. Polyamide fabric is a high infrared transmittance material in a dry state, that is, it has a low infrared absorption (emission) rate, so it will not affect the high infrared reflectivity of the inner layer, nor will it dissipate heat due to the infrared emission of the outer layer, thus reducing the heat retention effect. Polyethylene fiber fabric also has high infrared transmittance characteristics, and since it is necessary to construct a one-way moisture-wicking structure so that it can quickly wick away moisture and form an infrared emission structure when sweating, it is necessary to make the polyethylene fiber fabric highly absorbent. By utilizing the capillary effect of the polyethylene fiber with an irregular cross section, the water absorption of the polyethylene fiber fabric can be improved.

[0029] In some embodiments, the difference in water contact angle between the absorbent fabric layer and the infrared high-reflectivity porous hydrophobic layer is greater than 40°, preferably greater than 50°, and more preferably greater than 90°, and the contact angle of the absorbent fabric layer is smaller than that of the infrared high-reflectivity porous hydrophobic layer. In other embodiments, the moisture absorption rate of the absorbent fabric layer is higher than that of the infrared high-reflectivity porous hydrophobic layer, and the moisture absorption rate is 1.2-5 times that of the infrared high-reflectivity porous hydrophobic layer. Through the difference in moisture absorption and the porous structure of the inner layer, sweat can be rapidly penetrated and transported outward under the action of pressure difference.

[0030] The infrared high reflectance porous hydrophobic layer has a thickness of 200-400 μm, a pore size of 0.1-2 mm, a pore spacing of 3-20 mm, and a porosity of 10-50%, preferably 20-30%.

[0031] The pores of the infrared high-reflectivity porous hydrophobic layer are filled with a hydrophilic material. This hydrophilic material is either pre-filled into the pores of the infrared high-reflectivity porous hydrophobic layer, or the infrared high-reflectivity porous hydrophobic layer is first coated onto the inner side of an absorbent fabric layer, and then the hydrophilic fibers of the absorbent fabric layer are pressed to fill the pores of the infrared high-reflectivity porous hydrophobic layer. By filling the pores with hydrophilic material, sweat is facilitated to be transported and discharged from the pores; on the other hand, sweat is allowed to permeate the pores, thus giving the inner layer high infrared emissivity and improving the infrared radiation heat dissipation effect.

[0032] The infrared high-reflectivity porous hydrophobic layer is a porous metal film; preferably, the porous metal film is formed from one or more of gold, silver, and aluminum. Preferably, the porous metal film is adhered to the inner side of the absorbent fabric layer by means of coating and pressing, and the hydrophilic fibers are pressed and filled into the pores of the porous metal film during the pressing process.

[0033] Preferably, the inner side of the absorbent fabric layer is brushed to form hydrophilic short fibers, so that the hydrophilic short fibers can be pressed into the pores of the porous metal membrane.

[0034] An application of a self-regulating heat-insulating and cooling fabric is disclosed. The self-regulating heat-insulating and cooling fabric is used in the preparation of close-fitting warm and cooling clothing. When the self-regulating heat-insulating and cooling fabric is in a dry state, the infrared blocking effect of the infrared high reflectivity porous hydrophobic layer gives the clothing a warming effect. When human sweat makes the self-regulating heat-insulating and cooling fabric wet, the self-regulating heat-insulating and cooling fabric is converted to infrared high reflectivity, thereby realizing the infrared radiation heat dissipation and cooling function.

[0035] Example 1

[0036] A self-regulating heat-insulating and cooling fabric includes a porous aluminum film inner layer and a polyamide fiber fabric outer layer. The porous aluminum film has a thickness of approximately 300 μm, a pore size of approximately 0.8 mm, a pore spacing of 10 mm, and is filled with polyamide fibers.

[0037] Examples 2-7

[0038] A self-regulating heat-insulating and cooling fabric, compared with Example 1, differs in that the pore size and pore spacing of the porous aluminum film are shown in Table 1, while the rest are roughly the same as Example 1, and will not be described again here.

[0039] Table 1. Preparation conditions and performance test results of Examples 1-7

[0040]

[0041]

[0042] from Figure 2 It can be seen that the fabric of the present invention has a large reflectivity of 8-13μm in the dry state, indicating slow heat dissipation and thus good heat preservation effect; when it is wet, the reflectivity of 8-13μm is significantly reduced, heat dissipation is enhanced, so it can spontaneously cool down and thus regulate and maintain temperature-related constantness.

[0043] from Figure 3 It can be seen that the fabric prepared by this invention can maintain a temperature higher than the skin surface temperature and higher than that of cotton fabric in low-temperature environments, indicating that the present invention has a superior warmth retention effect. From Figure 4 It can be seen that when the fabric prepared by this invention is wet with sweat, the temperature is slightly lower than that of cotton fabric. Therefore, in practical applications, when excessive warmth is applied and sweating occurs, heat dissipation will be accelerated, thereby keeping the human body at a relatively comfortable temperature.

[0044] As shown in Table 1, when the aperture spacing is too small, the reflectivity in the 8–13 μm range of the cooling mode is relatively high, indicating poor infrared radiation cooling effect. This is because small apertures make unidirectional moisture conduction difficult, preventing self-regulating cooling. When the apertures are too large, the reflectivity in the 8–13 μm range of the heating mode decreases. This is because the effective area of ​​the porous aluminum film decreases, leading to a reduction in infrared reflectivity and thus a decrease in heating effect. When the aperture spacing is too large, although the heating effect is better, the reduced unidirectional moisture conduction significantly lowers the reflectivity in the cooling mode, resulting in a weaker cooling effect.

[0045] Example 2

[0046] A self-regulating heat-insulating and cooling fabric, compared with Example 1, differs in that the porous aluminum film is replaced with a porous silver film. Otherwise, it is largely the same as Example 1 and will not be described again here.

[0047] In summary, the self-regulating heat-insulating and cooling fabric provided by this invention forms a one-way moisture-wicking and temperature-regulating structure through a hydrophilic outer layer with low infrared emissivity and a porous hydrophobic inner layer with high infrared reflectivity. This structure suppresses infrared radiation heat loss in a dry state, achieving heat retention. When the fabric becomes damp due to sweating, it converts to high infrared emissivity, thereby improving heat dissipation and ultimately achieving automatic regulation of heat retention and cooling. This invention features a simple preparation method, novel structure, convenient use, and significant economic value.

[0048] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A self-regulating heat-insulating and cooling fabric, characterized in that, It includes an absorbent fabric layer and an infrared highly reflective porous hydrophobic layer disposed on its inner side. The absorbent fabric layer has an infrared emissivity of less than 30% in the dry state and an infrared emissivity of more than 80% in the wet state. The pores of the infrared highly reflective porous hydrophobic layer have a hydrophilic structure. The infrared highly reflective porous hydrophobic layer close to the skin forms a one-way moisture-wicking structure from the inside out.

2. The self-regulating heat-insulating and cooling fabric according to claim 1, characterized in that, The absorbent fabric layer has an infrared emissivity of over 90% in a wet state and less than 20% in a dry state.

3. The self-regulating heat-insulating and cooling fabric according to claim 2, characterized in that, The absorbent fabric layer has an infrared emissivity of over 95% in a wet state and less than 10% in a dry state.

4. The self-regulating heat-insulating and cooling fabric according to claim 1, characterized in that, The absorbent fabric layer has a higher moisture absorption rate than the infrared high reflectance porous hydrophobic layer, and its moisture absorption rate is 1.2-5 times that of the infrared high reflectance porous hydrophobic layer.

5. The self-regulating heat-insulating and cooling fabric according to claim 2, characterized in that, The absorbent fabric layer is a polyamide fiber fabric, a hydrophilic polyethylene fiber fabric, or a blend of both; the hydrophilic polyethylene fiber fabric is a polyethylene fiber fabric with an irregular cross section or a polyethylene fiber fabric that has been hydrophilically coated or grafted; the irregular cross section is a peanut-shaped or cross-shaped cross section.

6. The self-regulating heat-insulating and cooling fabric according to claim 1, characterized in that, The thickness of the infrared high reflectivity porous hydrophobic layer is 200-400 μm, the pore size is 0.1-2 mm, and the pore spacing is 3-20 mm.

7. The self-regulating heat-insulating and cooling fabric according to claim 1, characterized in that, The pores of the infrared high reflectivity porous hydrophobic layer are filled with a hydrophilic material. The hydrophilic material is either pre-filled into the pores of the infrared high reflectivity porous hydrophobic layer, or the infrared high reflectivity porous hydrophobic layer is first coated on the inner side of the absorbent fabric layer, and then the hydrophilic fibers of the absorbent fabric layer are pressed to fill the pores of the infrared high reflectivity porous hydrophobic layer.

8. The self-regulating heat-insulating and cooling fabric according to claim 1, characterized in that, The infrared high-reflectivity porous hydrophobic layer is a porous metal film.

9. The self-regulating heat-insulating and cooling fabric according to claim 8, characterized in that, The porous metal film is formed from one or more of gold, silver, and aluminum.

10. The self-regulating heat-insulating and cooling fabric according to claim 9, characterized in that, The porous metal membrane is adhered to the inner side of the absorbent fabric layer by means of coating and pressing, and the hydrophilic fibers are pressed and filled into the pores of the porous metal membrane during the pressing process.

11. The self-regulating heat-insulating and cooling fabric according to claim 10, characterized in that, The inner side of the absorbent fabric layer is brushed to form hydrophilic short fibers, which are then pressed into the pores of the porous metal membrane.

12. The application of a self-regulating heat-insulating and cooling fabric according to any one of claims 1 to 11, characterized in that, The self-regulating heat-insulating and cooling fabric is used in the preparation of close-fitting warm and cooling clothing. When the self-regulating heat-insulating and cooling fabric is in a dry state, the infrared blocking effect of the infrared high reflectivity porous hydrophobic layer gives the clothing a warming effect. When human sweat soaks into the self-regulating heat-insulating and cooling fabric, the self-regulating heat-insulating and cooling fabric has high infrared emission to achieve infrared radiation heat dissipation and cooling function.

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