Color laminate for radiative cooling and radiative cooling material including same

Abstract

The present invention relates to a color laminate for radiative cooling and a radiative cooling material including same, the color laminate comprising: a colored layer comprising a first thermoplastic resin; a first light reflection layer formed on the colored layer and having a reflectance of 80% or more with respect to light having a wavelength of 780 to 1,300 nm and a transmittance of 70% or more with respect to visible light having a wavelength of 400 to 780 nm; a second light reflection layer which is formed on the first light reflection layer and in which a first metal protection layer, a metal layer, and a second metal protection layer are sequentially laminated; an adhesive layer formed on the second light reflective layer; and an infrared radiation layer formed on the adhesive layer.

Description

Color laminate for radiant cooling and radiant cooling material comprising the same

[0001] The present invention relates to a color laminate for radiant cooling, which has excellent visible light and infrared reflectivity and excellent infrared radiation, excellent cooling effect, and excellent color feeling, and is suitable for automobile exterior use, and a radiant cooling material comprising the same.

[0002] [Cross-reference with related applications]

[0003] This application claims the benefit of priority from Korean Patent Application No. 10-2023-0179086, filed December 11, 2023, the entire contents of which are incorporated herein by reference.

[0004] Cooling generally requires energy consumption. For example, general-purpose cooling devices such as refrigerators and air conditioners use energy to compress a refrigerant and then perform cooling by absorbing the heat generated when the compressed refrigerant expands. However, radiant cooling is a technology that can cool without consuming energy, unlike general-purpose cooling devices. To improve the efficiency of radiant cooling, it is important to properly control the absorptivity, reflectivity, and emissivity of light in each wavelength range. Most heat is generated from incident sunlight, which is divided into ultraviolet (UV), visible light, and infrared light. Reflecting light in each wavelength range can block the inflow of heat through sunlight. For example, on a sunny day, a black car that absorbs light well easily experiences an increase in interior temperature, whereas a white car that reflects light well rather than absorbing it experiences a relatively slower increase in interior temperature.

[0005] Various materials are used as materials for radiant cooling, including multilayer thin films made of polymers, inorganic materials, or ceramic materials, radiant cooling components including metal reflective layers, and paints including white pigments. The polymer materials generally have high absorption rates (emissivities) for infrared rays, but due to their material characteristics, they are easily degraded by ultraviolet rays, moisture, etc. when left outdoors, which has the disadvantage of a short lifespan. In the case of the multilayer thin films, in order to increase the emissivity for infrared rays, the number of layers must be increased, which has the limitation that it is difficult to achieve high-efficiency radiant cooling performance due to the increased solar absorption rate. In addition, materials including metal reflective layers are difficult to apply in real life due to the problem of low long-term stability due to oxidation of the metal and the unit price. In addition, such metal materials have problems of causing eye fatigue and light scattering because they reflect specularly. Paints including white pigments are not typically composed of materials with high extinction coefficients, so they have problems of insufficient infrared emissivity and ultraviolet reflectivity, resulting in insufficient radiant cooling performance.

[0006] As an alternative to these problems, Korean Patent No. 2154072 (Patent Document 1) discloses a coolant capable of implementing color in radiation cooling, comprising a first material that emits infrared rays to cause radiative cooling; and a second material that absorbs light in the visible light range, converts the wavelength, and emits it. However, as in Patent Document 1, the coolant, in which a second material such as a dye or semiconductor material is mixed with the first material that emits infrared rays through electromagnetic resonance, suffers from a problem of low UV reflectivity and insufficient radiative cooling capability.

[0007] Therefore, there is a need for research and development on materials that have excellent visible light and infrared reflectivity and excellent infrared radiation, resulting in excellent radiative cooling capabilities.

[0008] Accordingly, the present invention provides a laminate having excellent visible light and infrared reflectivity, excellent infrared radiation, excellent radiant cooling ability, and excellent color sense, suitable for use as an exterior material for mobility, and a radiant cooling material including the laminate.

[0009] The present invention comprises a coloring layer comprising a first thermoplastic resin;

[0010] A first light reflective layer formed on the above-mentioned coloring layer, having a reflectivity of 80% or more for light having a wavelength of 780 to 1,300 nm and a transmittance of 70% or more for visible light having a wavelength of 400 to 780 nm;

[0011] A second light reflective layer formed on the first light reflective layer, in which a first metal protective layer, a metal layer, and a second metal protective layer are sequentially laminated;

[0012] An adhesive layer formed on the second light reflecting layer; and

[0013] A color laminate for radiation cooling is provided, comprising an infrared emitting layer formed on the adhesive layer.

[0014] Furthermore, the present invention provides a radiation cooling material including the color laminate for radiation cooling.

[0015] In addition, the present invention provides a mobility comprising the above-described material for radiation cooling.

[0016] The color laminate for radiation cooling according to the present invention has excellent visible light and infrared reflectivity and excellent infrared radiation, and thus has excellent radiation cooling performance. In addition, the color laminate for radiation cooling has excellent emissivity for a wavelength of 8 to 14 ㎛, which is an atmospheric window, and thus has excellent radiation cooling performance. Furthermore, the color laminate for radiation cooling has excellent radiation cooling performance and color sense due to low absorption of heat energy by convection, and thus can be suitably used as a material in various fields requiring materials with excellent radiation cooling performance, such as mobility, especially automobile exteriors.

[0017] FIG. 1 is a cross-sectional view of a color laminate for radiation cooling according to one embodiment of the present invention.

[0018] Figures 2 and 3 show the results of measuring the reflectivity of a laminate according to one embodiment of the present invention.

[0019] Figure 4 is a result of the internal temperature of a model vehicle using a color laminate for radiation cooling according to one embodiment of the present invention.

[0020] In this specification, when a part is said to "include" a certain component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0021] In this specification, when it is said that a member is located on the “surface”, “top”, “one side”, “other side” or “both sides” of another member, this includes not only cases where a member is in contact with another member, but also cases where another member exists between the two members.

[0022] In addition, in the present specification, “weight average molecular weight” can be measured by a method well known in the art, and can represent a value measured by, for example, a GPC (gel permeation chromatograph) method.

[0023] Color laminate for radiant cooling

[0024] A color laminate for radiation cooling according to the present invention comprises: a coloring layer; a first light reflecting layer formed on the coloring layer; a second light emitting layer formed on the first light reflecting layer; an adhesive layer formed on the second light reflecting layer; and an infrared emitting layer formed on the adhesive layer.

[0025] Referring to FIG. 1, a color laminate (A) for radiation cooling according to the present invention may include a form in which a coloring layer (100); a first light reflecting layer (200); a second light reflecting layer (300); an adhesive layer (400); and an infrared emitting layer (500) are sequentially laminated. At this time, the second light reflecting layer (300) includes a form in which a first metal protective layer (310), a metal layer (320), and a second metal protective layer (330) are sequentially laminated.

[0026] Additionally, the first light reflecting layer (200) may include a form in which a first layer (210) and a second layer (220) are alternately laminated.

[0027] Colored layer

[0028] The coloring layer serves to impart color to the laminate.

[0029] The above-mentioned coloring layer comprises a first thermoplastic resin. Specifically, the coloring layer comprises the first thermoplastic resin, has a color, and may be opaque. In this case, the coloring layer may be opaque, and thus, a laminate comprising the coloring layer may be applied in place of an exterior paint for automobiles.

[0030] In addition, the coloring layer can radiate long infrared rays with a wavelength of 4 to 20 μm in a broad band. As a result, it releases heat from the laminate including it, thereby improving the radiation cooling performance of the laminate.

[0031] The first thermoplastic resin may include at least one polymer selected from the group consisting of acrylonitrile-butadiene-styrene (ABS) resin and polycarbonate (PC). In this case, the "polymer" may include a homopolymer, or a blend or copolymer obtained therefrom.

[0032] In addition, the above-mentioned coloring layer can be applied without any special restrictions as long as the average thickness is a thickness that can be normally applied to the exterior of mobility.

[0033]

[0034] First light reflecting layer

[0035] The first light-reflecting layer reflects near-infrared rays with a wavelength of 780 to 1,300 nm to block heat.

[0036] The first light reflective layer has a reflectivity of 80% or more for light having a wavelength of 780 to 1,300 nm and a transmittance of 70% or more for visible light having a wavelength of 400 to 780 nm. Specifically, the first light reflective layer may have a high reflectivity of 80 to 90% for light having a wavelength of 780 to 1,300 nm and a transmittance of 75% or more or 80 to 95% for visible light having a wavelength of 400 to 780 nm. Accordingly, the first light reflective layer has the effect of improving radiant cooling capacity by reflecting near-infrared rays irradiated onto the laminate.

[0037] In addition, it is preferable that the first light reflecting layer is a polymer-containing layer rather than a metal-containing structure in consideration of economic feasibility. Specifically, the first light reflecting layer may include a first polymer-containing first layer and a second polymer-containing second layer having a lower refractive index than the first layer, which are alternately laminated. When the first light reflecting layer includes a first layer and a second layer having a lower refractive index than the first layer, which are alternately laminated, the first layer having a relatively high refractive index and the second layer having a relatively low refractive index are alternately laminated, so that each layer generates an interference effect with each other to change the direction of light propagation, thereby effectively blocking heat.

[0038] The first layer may have a refractive index of 1.4 or more, 1.6 to 2.2, or 1.8 to 2.0. When the refractive index of the first layer is within the above range, the first layer and the second layer generate an interference effect with each other to change the direction of light propagation, thereby improving the radiative cooling capacity of the laminate.

[0039] The second layer may have a refractive index of 1.3 or more, 1.5 to less than 2.1, or 1.7 to less than 1.9. When the refractive index of the second layer is within the above range, the first layer and the second layer generate an interference effect with each other, thereby changing the direction of light propagation, thereby improving the radiative cooling capacity of the laminate.

[0040] The above first light reflecting layer may have an average thickness of 50 to 300 μm, or 75 to 250 μm. If the average thickness of the first light reflecting layer is less than the above range, problems such as insufficient hardness of the manufactured laminate or a decrease in near-infrared reflectance may occur, and if it exceeds the above range, problems such as increased reflectance at undesired wavelengths of the manufactured laminate, a decrease in visible light transmittance, and a small obtainable effect relative to the thickness may occur, resulting in low economic feasibility.

[0041]

[0042] Second light reflective layer

[0043] The second light-reflecting layer reflects near-infrared rays with a wavelength of 1,300 to 2,500 nm to block heat and improve the durability of the laminate against sunlight.

[0044] The second light reflecting layer is formed on the first light reflecting layer, and includes a first metal protective layer, a metal layer, and a second metal protective layer sequentially laminated. The second light reflecting layer includes a first metal protective layer, a metal layer, and a second metal protective layer sequentially laminated, thereby improving the reflectivity for infrared rays having a wavelength of 1,300 nm or more, thereby improving the radiation cooling performance of the manufactured laminate.

[0045] The first metal protective layer and the second metal protective layer may each independently include at least one selected from the group consisting of indium-doped tin oxide (ITO), aluminum-doped zinc oxide (AZO), fluorine-dopped tin oxide (FTO), titanium dioxide (TiO2), neodymium oxide (Nd2O3), and silicon dioxide (SiO2). When each of the first metal protective layer and the second metal protective layer includes the metal oxides described above, there is an effect of preventing the metal layer from being oxidized upon exposure to air and controlling visible light transmittance.

[0046] In addition, the first metal protective layer and the second metal protective layer may each independently have an average thickness of 15 to 200 nm, 50 to 150 nm, or 30 to 100 nm. When the average thickness of each of the first metal protective layer and the second metal protective layer is less than the above range, the durability of the manufactured laminate may be lowered due to metal dissolution in the metal layer by external impact, or the metal layer may react with air and easily oxidize, resulting in a problem of lowering the durability of the metal layer and a problem of lowering the visible light transmittance, and when the above range is exceeded, the visible light transmittance of the manufactured laminate may be lowered or a problem of excessively increasing the near-infrared reflectance may occur.

[0047] The above metal layer may include, for example, at least one selected from the group consisting of silver (Ag), aluminum (Al), gold (Au), aluminum oxide (Al2O3), chromium (Cr), and copper (Cu). When the metal layer includes at least one of the metals described above, there is an effect of increasing the near-infrared reflectance of the laminate due to interference of light.

[0048] In addition, the metal layer may have an average thickness of 1 to 100 nm, 1 to 50 nm, 1 to 30 nm, or 1 to 20 nm. If the average thickness of the metal layer is less than the above range, a problem of insufficient near-infrared reflectance of the manufactured laminate may occur, and if it exceeds the above range, a problem of low economic feasibility may occur due to a small obtainable effect compared to the thickness of the metal layer.

[0049] The second light-reflecting layer may have an average thickness of 30 to 300 nm, 50 to 200 nm, or 50 to 150 nm. If the average thickness of the second light-reflecting layer is less than the above range, the near-infrared reflectance and visible light transmittance of the manufactured laminate may be insufficient, and if it exceeds the above range, the obtainable effect may be small compared to the thickness of the second light-reflecting layer, resulting in a problem of poor economic feasibility.

[0050]

[0051] adhesive layer

[0052] The above adhesive layer serves to bond between the second light reflecting layer and the infrared emitting layer.

[0053] Additionally, the adhesive layer may include a UV-curable adhesive or a moisture-curable adhesive. The adhesive layer may include at least one selected from the group consisting of an acrylic adhesive, a silicone adhesive, and a urethane adhesive.

[0054] The above UV-curable adhesive can be used without any special restrictions as long as it is an adhesive that is usually cured by UV rays, and may include, for example, an acrylic monomer and an UV photoinitiator.

[0055] The above acrylic monomer can be used without any special limitation as long as it is an acrylic monomer that can be commonly applied to a UV-curable adhesive, and may include, for example, at least one selected from the group consisting of an alkyl (meth)acrylate monomer and an amide group-containing unsaturated (meth)acrylic monomer.

[0056] The above ultraviolet photoinitiator can be used without any special limitation as long as it is a photoinitiator that can be commonly applied to ultraviolet curing adhesives, and may be, for example, an acyl phosphine oxide compound.

[0057] The above moisture-curing adhesive can be used without any special restrictions as long as it is an adhesive that is typically cured by moisture in the air, and may be, for example, a urethane-based adhesive. In this case, the polyurethane-based adhesive may include a urethane-based prepolymer and a polyisocyanate.

[0058] At this time, the urethane-based prepolymer can act to harden the adhesive by reacting with polyisocyanate, including hydroxyl groups. In addition, the urethane-based prepolymer can be used without any special restrictions as long as it is generally applicable to urethane-based adhesives.

[0059] In addition, the above polyisocyanate can be used without any special restrictions as long as it is applicable to a urethane adhesive.

[0060] The above adhesive layer may have an average thickness of 0.1 to 1.0 μm, 0.15 to 0.75 μm, or 0.2 to 0.5 μm. If the average thickness of the adhesive layer is less than the above range, a problem of insufficient adhesive strength between the second light reflecting layer and the infrared emitting layer may occur, and if it exceeds the above range, a problem of increased infrared absorption of the manufactured laminate may occur.

[0061]

[0062] infrared radiating layer

[0063] The infrared emitting layer can selectively radiate a portion of long infrared rays with a wavelength of 4 to 20 μm. This serves to release heat within the laminate containing the infrared emitting layer, thereby enhancing the radiative cooling performance of the laminate. In this case, the wavelength selectively radiated by the infrared emitting layer may be 8 to 14 μm.

[0064] The infrared emitting layer may include a second thermoplastic resin. In this case, the second thermoplastic resin may have different optical properties, specifically, a refractive index and / or an absorption coefficient, from the first thermoplastic resin included in the coloring layer. That is, the infrared emitting layer may include a second thermoplastic resin having different optical properties from the first thermoplastic resin.

[0065] Accordingly, the colored layer and the infrared emitting layer, each of which comprises the first thermoplastic resin and the second thermoplastic resin, may have different optical properties and thus may emit and / or reflect different wavelengths. As described above, the laminate for radiation cooling according to the present invention, which comprises two types of thermoplastic resins with different optical properties in each layer, has excellent radiation cooling performance.

[0066] The second thermoplastic resin may include, for example, at least one selected from the group consisting of polyester, acrylic resin, polyolefin, polyurethane, polystyrene (PS), cellulose resin, silicone, and copolymers thereof. Specifically, the second thermoplastic resin may include at least one polymer selected from the group consisting of polypropylene (PP), polymethyl methacrylate (PMMA), polymethylpentene (PMP), ethylene tetrafluoroethylene (ETFE), polydimethylsiloxane (PDMS), polylactic acid (PLA), polyethylene terephthalate (PET), and copolymers thereof. At this time, the above “polymer” may include a homopolymer, or a blend or copolymer obtained therefrom.

[0067] Additionally, the second thermoplastic resin may have an emissivity of 75 to 95%, or 80 to 90%, at a wavelength of 8 to 14 μm. That is, the second thermoplastic resin has excellent emissivity at a wavelength of 8 to 14 μm, and thus may selectively radiate some of the long infrared rays. If the emissivity of the second thermoplastic resin is outside the above range, a problem of an increase in the surface temperature of the laminate may occur.

[0068] The above infrared emitting layer may have an average thickness of 10 to 180 ㎛, 20 to 150 ㎛, 50 to 120, or 60 to 100 ㎛. If the average thickness of the infrared emitting layer is less than and / or greater than the above range, the infrared emitting layer may be too thin, resulting in problems such as insufficient hardness and radiation performance of the manufactured laminate. If it exceeds the above range, the visible light transmittance of the infrared emitting layer may be reduced, or the obtainable effect may be small relative to the thickness, resulting in problems such as low economic feasibility.

[0069] The color laminate for radiation cooling according to the present invention as described above has excellent reflectivity for visible light and near-infrared rays with a wavelength of 750 to 2,500 nm and excellent far-infrared radiation with a wavelength of 2.5 ㎛ or more, so that it has excellent radiation cooling ability. In addition, the color laminate for radiation cooling has excellent selective emissivity for a wavelength of 8 to 14 ㎛, which is an atmospheric window, so that it has excellent radiation cooling ability. Furthermore, the color laminate for radiation cooling has excellent radiation cooling ability and excellent color feeling because it absorbs little heat energy by convection, so that it can be suitably used as a material in various fields that require materials with excellent radiation cooling ability, such as mobility, especially the exterior of automobiles.

[0070]

[0071] Radiant cooling materials

[0072] The radiation cooling material of the present invention includes the above-described radiation cooling color laminate.

[0073] For example, the above-mentioned radiant cooling material may be an external radiant cooling material, and specifically, may be applied to an external radiant cooling material for a mobility. When the above-mentioned radiant cooling material is applied to the external surface of a mobility, a colored layer of the radiant cooling material may be laminated on the surface of the mobility, and the infrared emitting layer may be the outermost layer. As a result, the laminate may absorb heat from the inside of the mobility, which is below the colored layer, and release it to the outside, thereby further enhancing the radiant cooling effect.

[0074] As described above, the above-mentioned radiant cooling material has excellent visible light and infrared reflectivity and excellent infrared radiation, and thus has excellent radiant cooling ability. In addition, the above-mentioned radiant cooling material has excellent emissivity for a wavelength of 8 to 14 ㎛, which is an atmospheric window, and thus has excellent radiant cooling ability. Furthermore, the above-mentioned radiant cooling material has excellent radiant cooling ability due to little absorption of heat energy by convection and has excellent color sense, and thus can be suitably used as a material in various fields that require materials with excellent radiant cooling ability, such as mobility, especially automobile exteriors.

[0075]

[0076] Mobility

[0077] The mobility of the present invention comprises the above-described radiant cooling material. As a result, the mobility exhibits excellent radiant cooling performance, enabling energy savings in summer cooling, resulting in excellent energy efficiency.

[0078] At this time, the mobility may include, for example, automobiles, airplanes, trains, ships, or various mobile robots.

[0079] Hereinafter, the present invention will be described in more detail through examples. However, these examples are provided solely to aid understanding of the present invention and are not intended to limit the scope of the present invention in any way.

[0080] Manufacturing Example 1. Manufacturing of laminate

[0081] As the first light-reflecting layer, a first light-reflecting layer with an average thickness of 75 ㎛ (transmittance for visible light (wavelength 400-780 nm): 88%, reflectance for near-infrared light (wavelength 780-1300 nm): 80%) (Manufacturer: Toray Film, Product name: PICASUS, high-refractive index layers and low-refractive index layers alternately laminated, each layer made of polymer) was used.

[0082] On the first light reflecting layer, a first metal protective layer was formed with an average thickness of 0.065 μm (65 nm) by a deposition method using an indium-doped tin oxide (ITO) target under an argon atmosphere, and a metal layer was formed with an average thickness of 0.01 μm (10 nm) on the first metal protective layer by a metal deposition method using an Ag Planar target under an argon atmosphere, and a second metal protective layer with an average thickness of 0.065 μm (65 nm) was formed on the metal layer using ITO in the same manner as the formation of the first metal protective layer, thereby manufacturing a first laminate.

[0083] Afterwards, a urethane adhesive was applied on the second metal protective layer to form an adhesive layer with an average thickness of 0.2 μm.

[0084] Thereafter, a second laminate was manufactured by laminating an infrared emitting layer with an average thickness of 100 μm composed of PMMA (weight average molecular weight (Mw): 72,000 g / mol) on the adhesive layer.

[0085]

[0086] Manufacturing examples 2 to 7.

[0087] A laminate was manufactured in the same manner as Manufacturing Example 1, except that the thickness and composition of each layer were adjusted as shown in Table 1.

[0088] Thickness of the first light reflecting layer (㎛) Thickness of each layer in the second light reflecting layer (㎛) Thickness of the adhesive layer (㎛) Thickness of the infrared ray emitting layer (㎛) First metal protective layerMetal layerSecond metal protective layerManufacturing example 1750.0650.010.0650.2100Manufacturing example 2750.065--0.2100Manufacturing example 3750.0650.010.065--Manufacturing example 4-0.0650.010.650.2100Manufacturing example 5750.0650.010.0650.250Manufacturing example 6750.0650.010.0650.2200Manufacturing example 775---0.2100

[0089]

[0090] Test Example 1: Characteristic Evaluation

[0091] The properties of the laminate of the manufacturing example were evaluated using the following method, and the results are shown in Table 2 and Figure 2.

[0092] Specifically, an integrating sphere was installed on an ultraviolet-visible spectrophotometer (UV-VIS spectrophotometer) and a Fourier transform infrared spectrometer (FT-IR), and then the reflectance, emissivity, and transmittance of the laminate of the manufacturing example for a wavelength of 0.2 to 20 ㎛ were measured, and then the average emissivity and average reflectance were calculated. At this time, the reflectance measurement results of the first laminate of Manufacturing Example 1 and the first laminate of Manufacturing Example 2 are shown in Fig. 2.

[0093] Average reflectance (%) for wavelengths 0.8 to 2.5 ㎛ Average transmittance (%) for wavelengths 0.4 to 0.8 ㎛ Average emissivity (%) for wavelengths 4 to 20 ㎛ Manufacturing example 1808090 Manufacturing example 2608090 Manufacturing example 3778310 Manufacturing example 4509090 Manufacturing example 5758270 Manufacturing example 6827590 Manufacturing example 7509090

[0094]

[0095] As shown in Table 2 and Fig. 3, the laminate of Manufacturing Example 1 is expected to have excellent radiative cooling ability as it has a selective emissivity of 90% for the atmospheric window of 8 to 14 ㎛ in wavelength and a broadband emissivity of 4 to 20 ㎛ in wavelength, and a high reflectivity of 80% for visible light of 0.4 to 0.8 ㎛ in wavelength.

[0096] In particular, as seen in Fig. 2, compared to the first laminate of Manufacturing Example 2, which has a thin first light-reflecting layer including only an ITO single layer, the first laminate of Manufacturing Example 1 is judged to have a significantly higher reflectivity of 50% or more for infrared rays with a wavelength of 1 ㎛ or more, and thus has a superior radiative cooling ability.

[0097]

[0098] Example 1. Preparation of color laminate

[0099] A color laminate for radiation cooling was manufactured by laminating a black colored layer (manufacturer: Polychem, product name: ABS sheet, average thickness: 100 ㎛) on the first light-reflecting layer of the second laminate of the above manufacturing example 1.

[0100]

[0101] Comparative Example 1.

[0102] Only black colored film (Manufacturer: Polychem, Product name: ABS sheet, Average thickness: 100㎛) was used.

[0103]

[0104] Test Example 2: Characteristic Evaluation

[0105] The reflectivity of the laminate of Example 1 and the film of Comparative Example 1 was measured in the same manner as in Test Example 1, and the results are shown in Fig. 3.

[0106] As shown in Fig. 3, the laminate of Example 1 is judged to have excellent radiant cooling ability because it has a high reflectivity for wavelengths of 1 ㎛ or more.

[0107] On the other hand, the colored film (Comparative Example 1) is judged to have a relatively significantly lower reflectivity compared to the laminate of Example 1, and thus its radiant cooling ability is relatively very poor.

[0108]

[0109] Additionally, a 13:1 scale mockup of the Genesis G80 vehicle was placed outdoors and the temperature inside the model vehicle was measured over time, and the results are shown in Fig. 4.

[0110] As shown in Fig. 4, compared to the colored film of Comparative Example 1, the average temperature inside the model vehicle of the laminate of Example 1 was lower by 3°C or more, indicating that the laminate of the present invention has excellent radiant cooling ability.

Claims

1. A coloring layer containing a first thermoplastic resin; A first light reflective layer formed on the above-mentioned coloring layer and having a reflectivity of 80% or more for light having a wavelength of 780 to 1,300 nm and a transmittance of 70% or more for visible light having a wavelength of 400 to 780 nm; A second light-reflecting layer formed on the first light-reflecting layer, wherein a first metal protective layer, a metal layer, and a second metal protective layer are sequentially laminated; An adhesive layer formed on the second light reflecting layer; and A color laminate for radiation cooling, comprising an infrared emitting layer formed on the adhesive layer.

2. In claim 1, A color laminate for radiant cooling, wherein the first thermoplastic resin comprises at least one polymer selected from the group consisting of acrylonitrile-butadiene-styrene (ABS) resin and polycarbonate (PC).

3. In claim 1, A color laminate for radiation cooling, wherein the first light reflecting layer includes a first layer containing a first polymer and a second layer containing a second polymer having a lower refractive index than the first layer, which are alternately laminated.

4. In claim 1, The above first light reflecting layer has an average thickness of 50 to 300 ㎛, A color laminate for radiation cooling, wherein the second light reflecting layer has an average thickness of 30 to 300 nm.

5. In claim 1, A color laminate for radiation cooling, wherein the first metal protective layer and the second metal protective layer each independently include at least one selected from the group consisting of indium-doped tin oxide (ITO), aluminum-doped zinc oxide (AZO), fluorine-dopped tin oxide (FTO), titanium dioxide (TiO2), neodymium oxide (Nd2O3), and silicon dioxide (SiO2).

6. In claim 1, A color laminate for radiation cooling, wherein the metal layer comprises at least one selected from the group consisting of silver (Ag), aluminum (Al), gold (Au), aluminum oxide, chromium (Cr), and copper (Cu).

7. In claim 1, A color laminate for radiation cooling, wherein the adhesive layer comprises an ultraviolet curable adhesive or a moisture curable adhesive.

8. In claim 1, A color laminate for radiation cooling, wherein the adhesive layer comprises at least one selected from the group consisting of an acrylic adhesive, a silicone adhesive, and a urethane adhesive.

9. In claim 1, The above adhesive layer has an average thickness of 0.1 to 1.0 ㎛, A color laminate for radiation cooling, wherein the infrared emitting layer has an average thickness of 10 to 180 ㎛.

10. In claim 1, A color laminate for radiation cooling, wherein the infrared emitting layer comprises a second thermoplastic resin having optical properties different from those of the first thermoplastic resin.

11. A radiation cooling material comprising a color laminate for radiation cooling according to any one of claims 1 to 10.

12. In claim 11, Radiation cooling material, which is an external radiant cooling material.

13. A mobility comprising the radiation cooling material of claim 11.

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