阅读说明：本技术 辐射制冷功能层、辐射制冷面料及其制备方法 (Radiation refrigeration functional layer, radiation refrigeration fabric and preparation method thereof ) 是由 黄安冲 杨剑 其他发明人请求不公开姓名 于 2019-11-06 设计创作，主要内容包括：本发明公开了辐射制冷功能层、辐射制冷面料及其制备方法。其中辐射制冷面料包括柔性基材层以及设置在柔性基材层上的辐射制冷功能层,辐射制冷功能层,包括：第一功能层,其设置在柔性基材层上,第一功能层包括第一辐射制冷功能树脂；以及由辐射制冷功能粉料形成的第二功能层,辐射制冷功能粉料铺设于第一功能层的表面,辐射制冷功能粉料与第一辐射制冷功能树脂粘接,辐射制冷功能粉料的粒径为1μm~40μm。本发明的辐射制冷功能层在较低的厚度下即可获得高的辐射制冷效率,将其应用在辐射制冷面料中,有利于保持辐射制冷面料的柔韧性,提高辐射制冷面料的应用范围,也有利于降低辐射制冷面料的成本。(The invention discloses a radiation refrigeration functional layer, a radiation refrigeration fabric and a preparation method thereof. Wherein radiation refrigeration surface fabric includes flexible substrate layer and sets up the radiation refrigeration functional layer on flexible substrate layer, and radiation refrigeration functional layer includes: the first functional layer is arranged on the flexible base material layer and comprises a first radiation refrigeration functional resin; and the second functional layer is formed by radiation refrigeration functional powder, the radiation refrigeration functional powder is laid on the surface of the first functional layer and is bonded with the first radiation refrigeration functional resin, and the particle size of the radiation refrigeration functional powder is 1-40 microns. The radiation refrigeration functional layer can obtain high radiation refrigeration efficiency under a lower thickness, and is applied to the radiation refrigeration fabric, so that the flexibility of the radiation refrigeration fabric is kept, the application range of the radiation refrigeration fabric is improved, and the cost of the radiation refrigeration fabric is reduced.)

1. A radiation refrigerating functional layer adapted to be disposed on a substrate, said radiation refrigerating functional layer comprising:

a first functional layer adapted to be disposed on the substrate, the first functional layer comprising a first radiation refrigerating functional resin; and

the second functional layer is formed by radiation refrigeration functional powder, the radiation refrigeration functional powder is fixedly laid on the surface of the first functional layer, the radiation refrigeration functional powder is bonded with the first radiation refrigeration functional resin, and the particle size of the radiation refrigeration functional powder is 1-40 microns.

2. A radiation cooling function layer according to claim 1, wherein the thickness of said first function layer is 10 μm to 30 μm, the particle size of said radiation cooling function powder is 0.5 to 1.5 times the thickness of said first function layer, and the addition amount of said radiation cooling function powder is 10g/m ²~200g/m ²The radiation refrigeration functional powder is spherical or ellipsoidal.

3. A radiation-cooling functional layer according to claim 1, wherein the first radiation-cooling functional resin is selected from one or more of epoxy, polyester, polyurethane, acrylic, silicone; the radiation refrigeration functional powder is selected from one or more of ceramic powder, titanium dioxide, glass beads, silicon dioxide, coarse whiting powder, barium sulfate, talcum powder, zinc sulfate, aluminum silicate, coarse whiting powder, pearl powder, aluminum oxide, zinc oxide, zirconium oxide, cerium oxide, lanthanum oxide, rhodium oxide and magnesium oxide.

4. The radiation cooling functional layer according to any one of claims 1 to 3, further comprising a third functional layer disposed on the second functional layer, wherein the thickness of the third functional layer is 10 μm to 30 μm, the third functional layer comprises a second radiation cooling functional resin, the second radiation cooling functional resin is bonded to the radiation cooling functional powder, and the second radiation cooling functional resin is one or more selected from epoxy resin, polyester, polyurethane, acrylic resin, and silicone resin.

5. A radiation refrigerating functional layer according to any one of claims 1 to 3 wherein the emissivity of the radiation refrigerating functional layer 200 in the wavelength range of 7 μm to 14 μm is not less than 90% and the reflectivity in the wavelength range of 300nm to 2500nm is not less than 88%.

6. A radiation refrigeration fabric, characterized by comprising a flexible substrate layer and a radiation refrigeration functional layer arranged on the flexible substrate layer, wherein the radiation refrigeration functional layer is as claimed in any one of claims 1 to 5, and the first functional layer is arranged on the flexible substrate layer.

7. The radiation refrigeration fabric according to claim 6, wherein the flexible substrate layer comprises a fabric layer, the thickness of the fabric layer is 300-2000 μm, the fabric layer is formed by weaving one or more of terylene, chinlon, acrylic fiber, silk, cotton and hemp fiber, the flexible substrate layer further comprises a resin coating layer arranged on one or two surfaces of the fabric layer, the thickness of the resin coating layer is 1-20 μm, and the material of the resin coating layer is selected from one or more of polyvinyl chloride, acrylic resin, epoxy resin, phenolic resin and polyurethane.

8. The radiation refrigeration fabric according to claim 6 or 7, further comprising a weather-resistant protective layer arranged on the radiation refrigeration functional layer, wherein the weather-resistant protective layer is made of one or more materials selected from fluorine-containing resin, epoxy resin, polyester, polyurethane, acrylic resin and organic silicon resin, and the thickness of the weather-resistant protective layer is 10-50 μm.

9. The preparation method of the radiation refrigeration fabric is characterized by comprising the following steps of:

a1, arranging a first radiation refrigeration functional resin on a substrate, and uniformly spraying radiation refrigeration functional powder on the first radiation refrigeration functional resin before the first radiation refrigeration functional resin is dried or solidified;

and A2, drying or curing the first radiation refrigeration functional resin, so that the radiation refrigeration functional powder is bonded with the first radiation refrigeration functional resin.

10. The method for preparing a radiation refrigeration fabric according to claim 9, wherein in step S1, the radiation refrigeration functional powder is atomized by a pneumatic spraying device, and then the atomized radiation refrigeration functional powder is uniformly sprayed on the first radiation refrigeration functional resin.

11. The method for preparing a radiation refrigerating fabric as claimed in claim 9 or 10, wherein the step S2 is followed by the following steps: s3, arranging a second radiation refrigeration function resin on the radiation refrigeration function powder, and then drying or solidifying the second radiation refrigeration function resin to form a third function layer.

12. The method for preparing a radiation refrigerating fabric as claimed in claim 11, wherein the step S3 is followed by the following steps: and S4, arranging weather-proof resin on the third functional layer to form a weather-proof protective layer.

Technical Field

The invention relates to the technical field of radiation refrigeration, in particular to a radiation refrigeration functional layer, a radiation refrigeration fabric and a preparation method thereof.

Background

The radiation refrigeration fabric is formed by coating radiation refrigeration coating on base cloth, and forming a radiation refrigeration functional layer on the base cloth after the coating is dried, in order to achieve a better radiation refrigeration effect, the thickness of the radiation refrigeration functional layer generally needs to be more than 100 micrometers, but the thicker radiation refrigeration functional layer can cause the flexibility of the fabric to be poor, and the coating is easy to crack, so that the application of the existing radiation refrigeration fabric is limited. In addition, a thicker radiation cooling functional layer also means a higher cost.

Disclosure of Invention

An object of the present invention is to provide a radiation refrigeration functional layer which is thin and has high radiation refrigeration efficiency.

Another object of the present invention is to provide a radiation refrigeration fabric which has good flexibility and high radiation refrigeration efficiency.

According to one aspect of the present invention, there is provided a radiation refrigerating functional layer adapted to be disposed on a substrate, comprising:

a first functional layer adapted to be disposed on the substrate, the first functional layer comprising a first radiation refrigerating functional resin; and

the second functional layer is formed by radiation refrigeration functional powder, the radiation refrigeration functional powder is fixedly laid on the surface of the first functional layer, the radiation refrigeration functional powder is bonded with the first radiation refrigeration functional resin, and the particle size of the radiation refrigeration functional powder is 1-40 microns.

In some embodiments, the thickness of the first functional layer is 10 μm to 30 μm, the particle size of the radiation refrigeration functional powder is 0.5 to 1.5 times of the thickness of the first functional layer, and the addition amount of the radiation refrigeration functional powder is 10g/m ²~200g/m ²The radiation refrigeration functional powder is spherical or ellipsoidal.

In some of these embodiments, the first radiation-cooling functional resin is selected from one or more of epoxy, polyester, polyurethane, acrylic, silicone; the radiation refrigeration functional powder is selected from one or more of ceramic powder, titanium dioxide, glass beads, silicon dioxide, coarse whiting powder, barium sulfate, talcum powder, zinc sulfate, aluminum silicate, coarse whiting powder, pearl powder, aluminum oxide, zinc oxide, zirconium oxide, cerium oxide, lanthanum oxide, rhodium oxide and magnesium oxide.

In some embodiments, the radiation refrigeration functional layer further comprises a third functional layer arranged on the second functional layer, the thickness of the third functional layer is 10 μm to 30 μm, the third functional layer comprises a second radiation refrigeration functional resin, the second radiation refrigeration functional resin is bonded with the radiation refrigeration functional powder, and the second radiation refrigeration functional resin is selected from one or more of epoxy resin, polyester, polyurethane, acrylic resin and organic silicon resin.

In some embodiments, the emissivity of the radiation refrigeration functional layer 200 in a wavelength band of 7-14 μm is not lower than 90%, and the reflectivity in a wavelength band of 300-2500 nm is not lower than 88%.

According to another aspect of the invention, a radiation refrigeration fabric is provided, which comprises a flexible substrate layer and the radiation refrigeration functional layer arranged on the flexible substrate layer, wherein the first functional layer is arranged on the flexible substrate layer.

In some embodiments, the flexible substrate layer comprises a fabric layer, the thickness of the fabric layer is 300-2000 μm, the fabric layer is formed by weaving one or more of terylene, chinlon, acrylic fiber, silk, cotton and hemp fiber, the flexible substrate layer further comprises a resin coating layer arranged on one side or two sides of the fabric layer, the thickness of the resin coating layer is 1-20 μm, and the material of the resin coating layer is selected from one or more of polyvinyl chloride, acrylic resin, epoxy resin, phenolic resin and polyurethane.

In some embodiments, the radiation refrigeration fabric further comprises a weather-resistant protective layer arranged on the radiation refrigeration functional layer, the weather-resistant protective layer is made of one or more of fluorine-containing resin, epoxy resin, polyester, polyurethane, acrylic resin and organic silicon resin, and the thickness of the weather-resistant protective layer is 10-50 μm.

According to another aspect of the invention, a preparation method of a radiation refrigeration fabric is provided, which comprises the following steps:

a1, arranging a first radiation refrigeration functional resin on a substrate, and uniformly spraying radiation refrigeration functional powder on the first radiation refrigeration functional resin before the first radiation refrigeration functional resin is dried or solidified;

and A2, drying or curing the first radiation refrigeration functional resin, so that the radiation refrigeration functional powder is bonded with the first radiation refrigeration functional resin.

In some embodiments, in step S1, the radiation refrigeration function powder is atomized by using a pneumatic spraying device, and then the atomized radiation refrigeration function powder is uniformly sprayed on the first radiation refrigeration function resin.

In some embodiments, the step S2 is followed by the following steps: s3, arranging a second radiation refrigeration function resin on the radiation refrigeration function powder, and then drying or solidifying the second radiation refrigeration function resin to form a third function layer.

In some embodiments, the step S3 is followed by the following steps: and S4, arranging weather-proof resin on the third functional layer to form a weather-proof protective layer.

Compared with the prior art, the invention has the beneficial effects that: the radiation refrigeration functional layer can obtain high radiation refrigeration efficiency under a lower thickness, and is applied to the radiation refrigeration fabric, so that the flexibility of the radiation refrigeration fabric is kept, the application range of the radiation refrigeration fabric is improved, and the cost of the radiation refrigeration fabric is reduced.

Drawings

FIG. 1 is a schematic view of a first embodiment of a radiation-cooled fabric of the present invention;

FIG. 2 is a schematic view of a second embodiment of a radiation-cooled fabric of the present invention;

FIG. 3 is a schematic view of a third embodiment of a radiation-cooled fabric of the present invention;

FIG. 4 is a schematic view of a fourth embodiment of a radiation-cooled fabric of the present invention;

in the figure:

100. a flexible substrate layer;

200. a radiation refrigeration functional layer;

210. a first functional layer;

220. a second functional layer; 221. powder with radiation refrigeration function

230. A third functional layer;

300. and (7) a weather-resistant protective layer.

Detailed Description

The present invention is further described below with reference to specific embodiments, and it should be noted that, without conflict, any combination between the embodiments or technical features described below may form a new embodiment.

In the description of the present invention, it should be noted that, for the terms of orientation, such as "central", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., the terms of orientation and positional relationship indicate that the orientation or positional relationship shown in the drawings is based on, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as limiting the specific scope of the present invention.

It is noted that the terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

The terms "comprises," "comprising," and "having," and any variations thereof, in the description and claims of this application, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The invention provides a radiation refrigeration fabric, which comprises a flexible substrate layer 100 and a radiation refrigeration functional layer 200 arranged on the flexible substrate layer 100, as shown in fig. 1 and 2. In some embodiments, the radiation-refrigerating face fabric further comprises a weather-resistant protective layer 300 disposed on the radiation-refrigerating functional layer 200, as shown in fig. 3 and 4.

As shown in fig. 1-4, the radiation refrigerating functional layer 200 includes a first functional layer 210 and a second functional layer 220.

The first functional layer 210 is disposed on the flexible substrate layer 100, and the first functional layer 210 includes a first radiation refrigerating functional resin. The first radiation refrigeration functional resin has high emissivity in a wave band of 7-14 mu m, and can be one or more of epoxy resin, polyester, polyurethane, acrylic resin and organic silicon resin. Preferably, the thickness of the first functional layer 210 is 10 μm to 30 μm.

The second functional layer 220 is formed by radiation refrigeration function powder 221, the radiation refrigeration function powder 221 is laid on the surface of the first functional layer 210, the radiation refrigeration function powder 221 is bonded with the first radiation refrigeration function resin, and the particle size of the radiation refrigeration function powder is 1-40 microns. Preferably, the particle size of the radiation refrigeration function powder 221 is 0.5-1.5 times of the thickness of the first functional layer 210, and the addition amount of the radiation refrigeration function powder is 10g/m ²~200g/m ². The radiation refrigeration functional powder is used for improving the reflectivity of the radiation refrigeration functional layer 200 in a wave band of 300 nm-2500 nm. The radiation refrigeration functional powder material can be one or more selected from ceramic powder, titanium dioxide, glass beads, silicon dioxide, coarse whiting powder, barium sulfate, talcum powder, zinc sulfate, aluminum silicate, coarse whiting powder, pearl powder, aluminum oxide, zinc oxide, zirconium oxide, cerium oxide, lanthanum oxide, rhodium oxide and magnesium oxide. The shape of the radiation refrigeration functional powder is preferably spherical or ellipsoidal.

It is worth mentioning that the radiation refrigeration function powder forms a single layer of dry powder only on the surface of the first radiation refrigeration function resin, in other words, the thickness of the second function layer is less than or equal to the grain size of the radiation refrigeration function powder.

The second functional layer 220 can greatly improve the reflectivity of the radiation refrigeration functional layer 200, so as to improve the radiation refrigeration efficiency of the radiation refrigeration functional layer 200 in the daytime. The radiation refrigeration functional layer 200 can have a reflectivity of more than 88% in a wave band of 300 nm-2500 nm under the condition that the thickness is not more than 50 mu m, and the radiation refrigeration functional layer 200 is applied to a fabric, so that the radiation refrigeration fabric with good flexibility and high radiation refrigeration effect can be obtained.

In some embodiments of first functional layer 210, first functional layer 210 further comprises a first particulate filler dispersed in the first radiation refrigerating functional resin. The first particle filler can be selected from fillers with high emissivity in a wave band of 7-14 mu m and high reflectivity in a wave band of 300-2500 nm. Specifically, the first particulate filler is selected from one or more of ceramic powder, titanium dioxide, glass beads, silicon dioxide, coarse whiting powder, barium sulfate, talcum powder, zinc sulfate, aluminum silicate, coarse whiting powder, pearl powder, aluminum oxide, zinc oxide, zirconium oxide, cerium oxide, lanthanum oxide, rhodium oxide and magnesium oxide. The particle size of the first particulate filler may be 4 to 20 μm.

In some embodiments of the radiation refrigeration functional layer 200, the radiation refrigeration functional layer 200 further includes a third functional layer 230 disposed on the second functional layer 220, the third functional layer 230 has a thickness of 10 μm to 30 μm, and the third functional layer 230 includes a second radiation refrigeration functional resin bonded to the radiation refrigeration functional powder of the second functional layer 220. The second radiation refrigeration functional resin has high emissivity in a wave band of 7-14 mu m, and can be one or more of epoxy resin, polyester, polyurethane, acrylic resin and organic silicon resin.

In some embodiments of the third functional layer 230, the third functional layer 230 further comprises a third particulate filler dispersed in the second radiation refrigerating functional resin. The third particle filler can be selected from fillers with high emissivity in a wave band of 7-14 mu m and high reflectivity in a wave band of 300-2500 nm, and can be one or more selected from ceramic powder, titanium dioxide, glass beads, silicon dioxide, coarse whiting powder, barium sulfate, talcum powder, zinc sulfate, aluminum silicate, coarse whiting powder, pearl powder, aluminum oxide, zinc oxide, zirconium oxide, cerium oxide, lanthanum oxide, rhodium oxide and magnesium oxide. The particle size of the third particulate filler may be 4 to 20 μm.

It is worth mentioning that when the thickness of the third functional layer 230 is smaller than the particle size of the radiation refrigeration function powder 221, a part of the radiation refrigeration function powder 221 may protrude from the upper surface of the third functional layer 230, as shown in fig. 4.

In some embodiments, the emissivity of the radiation refrigeration functional layer 200 in the 7 μm-14 μm band is not less than 90%, and the reflectivity in the 300 nm-2500 nm band is not less than 88%.

In some embodiments of the flexible substrate layer 100, the flexible substrate layer 100 includes a fabric layer, the thickness of the fabric layer is 300 μm to 2000 μm, and the fabric layer may be formed by weaving one or more of polyester, nylon, acrylic, silk, cotton, hemp, and other fibers.

In other embodiments of the flexible substrate layer 100, the flexible substrate layer 100 includes a fabric layer and a resin coating layer disposed on one or both sides of the fabric layer, the thickness of the fabric layer is 300 μm to 2000 μm, and the thickness of the resin coating layer is 1 μm to 20 μm. The fabric layer can be formed by spinning one or more of terylene, chinlon, acrylon, silk, cotton, hemp and other fibers. The material of the resin coating layer may be selected from one or more of polyvinyl chloride, acrylic resin, epoxy resin, phenolic resin, polyurethane.

The material of the weather-resistant protective layer 300 may be one or more selected from fluorine-containing resin, epoxy resin, polyester, polyurethane, acrylic resin, and silicone resin. The transmissivity of the weather-proof protective layer is more than or equal to 80 percent. The thickness of the weather-resistant protective layer is 10-50 μm.

The invention also provides a preparation method of the radiation refrigeration fabric, which comprises the following steps:

s1, arranging a first radiation refrigeration functional resin on a base material, and uniformly spraying radiation refrigeration functional powder on the first radiation refrigeration functional resin before the first radiation refrigeration functional resin is dried or solidified;

and S2, drying or curing the first radiation refrigeration functional resin, so that the radiation refrigeration functional powder is bonded with the first radiation refrigeration functional resin.

It should be noted that the term "curing" in the present invention may be, but is not limited to, thermal curing, photo-curing, natural air-drying, etc. The first radiation refrigeration functional resin can be arranged on the base material by adopting a coating mode, a spraying mode, a brush coating mode and the like.

In some embodiments, in step S1, the radiation refrigeration functional powder is atomized by using a pneumatic spraying device, and then the atomized radiation refrigeration functional powder is uniformly sprayed on the first radiation refrigeration functional resin.

In some embodiments, step S2 is followed by the following steps: s3, arranging a second radiation refrigeration functional resin on the radiation refrigeration functional powder, and then drying or curing the second radiation refrigeration functional resin to form a third functional layer.

In some embodiments, step S3 is followed by the following steps: and S4, arranging weather-resistant resin on the third functional layer to form a weather-resistant protective layer.

[ example 1 ]

Preparing a radiation refrigeration fabric:

(1) providing a flexible base material which comprises polyester woven cloth and polyvinyl chloride resin coated on two sides of the polyester woven cloth, wherein the thickness of the polyester woven cloth is 1mm, and the thickness of resin coating layers on two sides of the polyester woven cloth is 10 micrometers;

(2) coating PET resin with the thickness of 20 microns on a flexible base material, uniformly spraying a layer of titanium dioxide with the average particle size of 10 microns on the surface of the PET resin before the resin is dried, and drying the PET resin;

(3) the PET resin was coated on the titanium dioxide powder to a thickness of 20 μm, and then the PET resin was dried.

[ example 2 ]

Preparing a radiation refrigeration fabric:

(1) providing a flexible base material which comprises polyester woven cloth and polyvinyl chloride resin coated on two sides of the polyester woven cloth, wherein the thickness of the polyester woven cloth is 1mm, and the thickness of resin coating layers on two sides of the polyester woven cloth is 10 micrometers;

(2) coating polyacrylic acid (PAA) resin with the thickness of 20 microns on a flexible base material, uniformly spraying a layer of talcum powder with the average particle size of 20 microns on the surface of the polyacrylic acid (PAA) resin before the resin is dried, and drying the polyacrylic acid (PAA) resin;

(3) polyacrylic acid (PAA) was coated on the talc powder to a thickness of 10 μm, and then the polyacrylic resin (PAA) resin was dried.

[ example 3 ]

Preparing a radiation refrigeration fabric:

(1) providing a flexible base material which comprises polyester woven cloth and polyvinyl chloride resin coated on two sides of the polyester woven cloth, wherein the thickness of the polyester woven cloth is 1mm, and the thickness of resin coating layers on two sides of the polyester woven cloth is 10 micrometers;

(2) coating polyurethane resin with the thickness of 20 microns on a flexible base material, uniformly spraying a layer of silicon dioxide with the average particle size of 30 microns on the surface of the polyurethane resin before the resin is dried, and drying the PET resin;

(3) a polyurethane resin was coated on the silica to a thickness of 10 μm, and then the polyurethane resin was dried.

[ example 4 ]

(1) Providing a flexible base material which comprises polyester woven cloth and polyvinyl chloride resin coated on two sides of the polyester woven cloth, wherein the thickness of the polyester woven cloth is 1mm, and the thickness of resin coating layers on two sides of the polyester woven cloth is 10 micrometers;

(2) coating a PET resin with the thickness of 20 microns on a flexible base material, mixing 10 volume percent of silicon dioxide with the average particle size of 10 microns in the PET resin layer, uniformly spraying a layer of titanium dioxide with the average particle size of 30 microns on the surface of the PET resin before the resin is dried, and drying the PET resin;

(3) coating PET resin with the thickness of 10 mu m on the titanium dioxide, mixing 5 percent of silicon dioxide with the volume fraction and the average grain diameter of 6 mu m into the PET resin layer, and then drying the PET resin.

[ example 5 ]

(1) Providing a flexible base material which comprises polyester woven cloth and polyvinyl chloride resin coated on two sides of the polyester woven cloth, wherein the thickness of the polyester woven cloth is 1mm, and the thickness of resin coating layers on two sides of the polyester woven cloth is 10 micrometers;

(2) coating PET resin with the thickness of 20 microns on a flexible base material, mixing titanium dioxide with the volume fraction of 15% and the average particle size of 10 microns in the PET resin, uniformly spraying a layer of silicon dioxide with the average particle size of 30 microns on the surface of the PET resin before the resin is dried, and drying the PET resin;

(3) a 10 μm thick PET resin mixed with 12% volume fraction of pearl powder was coated on the silica, and then the PET resin was dried.

Comparative example 1

Preparing a radiation refrigeration fabric:

(1) providing a flexible base material which comprises polyester woven cloth and polyvinyl chloride resin coated on two sides of the polyester woven cloth, wherein the thickness of the polyester woven cloth is 1mm, and the thickness of resin coating layers on two sides of the polyester woven cloth is 10 micrometers;

(2) a50 μm thick PET resin in which silica having an average particle diameter of 10 μm was dispersed and the volume fraction of silica in the resin was 20% was coated on a flexible substrate.

(3) The PET resin was then dried.

Comparative example 2

Preparing a radiation refrigeration fabric:

(1) providing a flexible base material which comprises polyester woven cloth and polyvinyl chloride resin coated on two sides of the polyester woven cloth, wherein the thickness of the polyester woven cloth is 1mm, and the thickness of resin coating layers on two sides of the polyester woven cloth is 10 micrometers;

(2) the flexible base material is coated with polyurethane resin with the thickness of 100 mu m, titanium dioxide with the average particle size of 10 mu m is dispersed in the polyurethane resin, and the volume fraction of the titanium dioxide in the resin is 15%.

(3) The PET resin was then dried.

The above examples and comparative examples were tested for emissivity in the 7 μm to 14 μm band and reflectivity in the 300nm to 2500nm band, and the test results are shown in Table 1.

TABLE 1

	Emissivity of 7-14 mu m wave band	Reflectivity of 300 nm-2500 nm wave band
			Example 1	91.1%	89.2%
Example 2	92.4%	90.2%
			Example 3	92.7%	93.5%
Example 4	93.6%	93.8%
			Example 5	93.9%	93.4%
Comparative example 1	78.2%	75.1%
			Comparative example 2	79.5%	76.6%

The foregoing has described the general principles, principal features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.