KR20120002054A - Reflection paints of heat and a road pavement method using it - Google Patents

Abstract

PURPOSE: A heat-reflective paint is provided to decrease the surface temperature of a road pavement material by 7-15°C, and to obtain more than 70% of reflectivity in all sunlight wavelength areas. CONSTITUTION: A heat-reflective paint comprises a mixture of 30-50wt% room temperature-drying type acryl emulsion resin, 10-25wt% glass beads, 10-30wt% hollow ceramic, 10-30wt% colored inorganic pigment, 10-30wt% water, 1-5wt% surfactant, 1-5wt% thickening agent, 1-35wt% dispersant and 1-3wt% sedimentation agent. The glass beads is vacuum deposition-coated by aluminum or metal which has the thickness of 1-40 micron, on a glass of which refractive index is at least 2.2 or higher. The density of the hollow ceramic is 0.5-0.7g/cc, grain size is 15-65, the volume hollow rate is 20-60%.

Description

Reflective paints of heat and a road pavement method using it}

The present invention relates to a road pavement mixture, and more particularly, a heat-retardant reflective paint made by coating a heat-resistant reflective paint on a road pavement surface to have a heat shielding effect by reflecting or dissipating heat flowing into the pavement surface. It is about road pavement method.

In general, urban air temperature is a local heat island due to the inability to circulate natural solar energy due to the artificial surface cover by paving or buildings, and the increase in artificial arrangement by cooling or automobiles. lsland: The temperature is higher than the surrounding area due to air pollution or artificial heat.) is a frequent social problem.

Near-infrared ray belongs to 780 ~ 2100nm which is included in sunlight, and unlike infrared and visible light, it is a wavelength range that is easy to change according to thermal energy. When near-infrared rays are absorbed by the target material, they are converted into thermal energy. Asphalt and concrete pavements contain the heat, the pavement temperature rises. The general paint (paint) absorbs all the infrared rays from the sun and generates heat, so the road pavement surface rises to 60 ~ 70 ℃ in summer.

In recent years, various studies have been attempted as a countermeasure on the pavement surface for asphalt pavement. In addition, heat shield packaging has been proposed to improve the urban environment, and the heat shield packaging can improve the comfort of driving and walking as well as to prevent global warming by improving the heat island phenomenon caused by the radiant heat of the summer package. It is expected to have positive effects such as environmental improvement and road noise reduction of pavement.

Looking at the current status of domestic and foreign related technologies for heat shield paints,

(1) Overseas Technology

The foreign technology of heat shielding paint was initially focused on the heat shielding of buildings, but recently, it has been spurring technology development to apply to road paving in civil engineering centering around Japan. When applied to existing buildings, the emphasis was placed on thermal insulation performance because it is applied to non-structural structures that are not subjected to load.However, in order to apply to road pavement, there are many things to consider such as wear resistance and durability. In order to evaluate and expand the applicability of the system, JIS technical standards are being established.

The characteristics and status of the technology are as follows.

(1) “UNICOPS Mild” of Mitsumi Metallic Paint Chemicals in Japan is an acrylic emulsion resin-based, environmentally friendly, one-component water-based thick film type sunscreen. As a characteristic, white was used as the basic color, and high heat reflectivity, low thermal conductivity special silica or ceramic, etc., showed that the reflectance of the solar radiation energy was over 80% and the blocking rate was over 90%.

② 'Thermo shield', a product produced by Nagashima Specialty Paint, is a special functional paint related to heat and environmental conservation. The structure of the coating film is the same as that of the outer insulation layer of the space vehicle, and the ceramic ceramic bubbles are precisely arranged to occupy about 40% of the volume ratio. The coating film has a specific gravity of 1.11 and is light, reflects about 80% of sunlight, and has a thermal conductivity of 0.025 (kcal / mh ° C.). As a result, it is known that room temperature can be kept low even in summer by preventing heat transfer to the inside of the outside temperature.

③ Microntech's thermal insulation coating 'micro coat' was developed as a pigment mainly composed of ceramic beads. It has excellent barrier properties such as heat radiation, and is effective for aesthetics, insulation and moisture retention. It is known that the energy saving effect is 20 to 30% due to the temperature difference of about 6 to 10 degrees. In midsummer, when the room temperature is 30 ~ 34 ℃, the roof temperature of the light steel structure is 40 ~ 50 ℃. In the experiment, insulation effect of 6 ~ 10 ℃ was recognized, and it is reported that even buildings with openings have significant insulation effect. It is finished by painting the interior and exterior of the building and the roof. The colors are white, brown, off-white and various colors.

④ Toda Industrial Co., Ltd. has developed a black pigment for heat-shielding paint that realizes high light reflectivity with free of heavy metals. New black inorganic pigments for heat-resistant coatings were produced with zero heavy metals, which do not contain chromium-based materials, which have been mainly used up to now, using a composite oxide of iron oxide and Rare metal using wet synthesis method, which is an iron oxide production technology. In addition, it is suggested that the gray (N6) reflects more than 50% of infrared rays in the wavelength range of 780 to 2,100 nanometers and suppresses the temperature rise, and is excellent in weatherability and has black characteristics equivalent to those of carbon black.

⑤ NIPPO of Japan developed heat shield coating jointly with Nagashima special coating. The developed thermal insulation paint can lower the temperature of asphalt road surface above 60 ℃ by more than 15 ℃ during sunny day in summer. The heat shield packaging developed this time is an intensive study of the material and coating structure, and it can maintain the solar reflectance of more than 50% by graying the color of the packaging surface. Japan's Ministry of Land, Infrastructure, Transport and Tourism, Tokyo Metropolitan Government, and Yokohama City conducted performance tests and test constructions to evaluate the effect of temperature reduction on the developed pavement.

(2) Domestic technology

In Korea, hollow pigments are imported and heat-blocking or condensation prevention paints are simply mixed with paint. However, paints simply mixed with hollow pigments exposed the limitations of performance due to the inhomogeneity and weak durability.

Accordingly, the present invention was made to improve the above problems, the object of the present invention,

first; When applying the heat-reduced reflective paint on the asphalt or concrete pavement surface, the surface temperature of the road pavement can be reduced by about 7 ~ 15 ℃, and the solar reflectance in the full wavelength range of the solar light is 70% or more. .

second; The normal temperature-drying acrylic emulsion resin used as a main binder is to obtain an environmentally friendly product that can cope with the regulation of volatile organic compounds by avoiding the use of an organic solvent (thinner).

In order to achieve the above object, the present invention, the room temperature drying type acrylic emulsion resin 30-50% by weight, glass beads 10-25% by weight, hollow ceramic 10-30% by weight, colored inorganic pigment 10-30% by weight, water 10- It is obtained by mixing 30 weight%, surfactant 1-5 weight%, thickener 1-5 weight%, dispersing agent 1-3 weight%, and settling agent 1-3 weight%.

The glass beads may be applied to a glass having a refractive index of at least 2.2 or more and aluminum or metal having a thickness of 1 to 40 μm and coated by vacuum deposition.

The hollow ceramic, the density of 0.5-0.7 (g / cc), the particle size may be 15 to 65 and the hollow ratio of the volume 20 to 60% can be applied.

The room temperature drying type acrylic emulsion resin (Acrylate emulsion resin) is made of a copolymer of methyl methacryl and methacrylic acid.

When applying the above-mentioned heat-resistant reflective paint on the concrete or asphalt pavement surface,

Perform a primary coating layer forming step of forming a 0.1-0.5mm by applying a binder using rheology alkyd resin and a curing agent to the road pavement surface, and after the primary coating layer forming step, the heat-reduced reflection to the top surface What is necessary is just to perform the secondary coating layer forming step which mixes a coating material with silica sand and apply | coats it at 0.1-3 mm.

In addition, when applying heat-resistant reflective paint to the concrete or asphalt pavement that can be permeated and drained,

Perform the first coating layer forming step of applying a water-repellent polymer resin mixed with a rheology alkyd resin, and after the first coating step by mixing a heat-resistant low-reflective paint with silica sand on the upper surface to apply 0.1-3mm to the secondary What is necessary is just to perform the secondary coating layer forming step of apply | coating.

Therefore, the present invention has an effect of reducing the surface temperature of the road pavement by about 7 ~ 15 ℃ when applied to the asphalt concrete pavement surface by applying a heat-resistant reflective paint and the solar reflectance in the entire wavelength range of the solar light 70 It is effective to show more than%.

In addition, the room temperature drying type acrylic emulsion resin used as the main binder has an effect of obtaining an environmentally friendly product that can cope with the regulation of volatile organic compounds by not using an organic solvent (thinner).

1 is a cross-sectional view of a road pavement using a heat-resistant reflective paint according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may obscure the subject matter of the present invention. do.

The present invention relates to a heat reducing reflective coating.

Heat-resistant reflective paints according to the invention, the room temperature drying type acrylic emulsion resin 30-50% by weight, glass beads 10-25% by weight, hollow ceramic 10-30% by weight, colored inorganic pigments 10-30% by weight, water 10- It is obtained by mixing 30 weight%, surfactant 1-5 weight%, thickener 1-5 weight%, dispersing agent 1-3 weight%, and settling agent 1-3 weight%.

The glass bead is applied to a glass having a refractive index of at least 2.2 or more and aluminum or metal having a thickness of 1 to 40㎛ and coated by vacuum deposition.

The hollow ceramic has a density of 0.5-0.7 (g / cc), a particle size of 15 to 65, and a hollow ratio of 20 to 60% by volume.

The said room temperature drying type acrylic emulsion resin consists of a copolymer of methyl methacryl, methacrylic acid, and acrylamide.

The heat-reduced reflecting paints described above were applied to general roads or pavements for permeation and drainage.

On the road pavement surface, applying a binder using a rheology alkyd resin and a curing agent to form a binder using MDI to form a 0.1-0.5mm, and subsequently to the top surface after the primary coating layer forming step A secondary coating layer forming step was performed in which the thermally-reduced antireflective coating was mixed with silica sand and applied at 0.1-3 mm.

The water-permeable and drainable asphalt or concrete pavement surface was further mixed with the water-retaining polymer resin during the first coating layer forming step.

As described above, the heat-reduced reflective paint applied to the pavement surface will be described by the first and second embodiments, and the heat-reduced reflective paint will be described below.

<Experimental conditions> Acrylic Emulsion Resin Grasvid Hollow Ceramic Colored inorganic pigment water Surfactants Thickener Dispersant Sedimentant 30-50% by weight 10-25% by weight 10-30% by weight 10-30% by weight 10-30% by weight 1-5% by weight 1-5% by weight 1-3% by weight 1-3% by weight

First Embodiment

1. Experiment

1.1 Exam Outline

The indoor irradiation test is an experiment for evaluating the thermal insulation performance. The test method was carried out by citing Table 1 of the indoor irradiation test method of road surface temperature reduction performance evaluation of a fluid type thermal insulation pavement conducted by the Japanese Civil Engineering Center in 2008. The lamps used for the irradiation test are more versatile than those of the xenon lamps and beam lamps used by the Japan Thermal Protection Packaging Institute and the xenon lamps with wavelengths close to natural light. Beam lamp was selected. The beam lamp used in this experiment is Philips' 120W E27220-240V par38 30 °. In order to keep the temperature and humidity constant, the experiment was conducted in a constant temperature and humidity room. The surface temperature of the specimen was measured by measuring the three points of the heating table using a grounding thermometer and the average temperature was measured.

Indoor survey test method Item Heat shield packaging Assessment Methods After irradiation for 3 hours, the surface temperature of the heat-shielding pavement or water-retaining pavement is obtained under the test conditions at which the surface temperature of the comparative pavement reaches 60 ° C, and the temperature difference is evaluated as the road surface temperature reduction amount. Type of irradiation lamp Diffuse Beam Lamps BRF 110V 120W, Xenon Lamps XC-500EF Test and curing temperature 30 ± 1 ℃ Test and Curing Humidity 50 ± 5RH% Irradiation height Height (or irradiation amount) to 60 ℃ after 3 hours of surface temperature of comparative packaging Specimen
Curing time 5 hours or more Metric Surface temperature, temperature and humidity of constant temperature and humidity room Surface temperature measurement method Thermocouple specimen surface

1.2 Fabrication of specimens and insulation

Asphalt specimens used in this study were fabricated into 10 × 10 × 5cm squares, which were used for the thermal insulation paving test of the Japan Civil Engineering Center.

Figure 1. Construction of specimen and insulation

2. Experimental results

2.1 Thermal Performance Evaluation

① asphalt concrete pavement

Asphalt pavement test specimen and asphalt specimen coated with heat-resistant antireflective paint were tested at room temperature 30 ± 1 ℃ by the indoor investigation test method for evaluation of road surface temperature reduction performance of fluid-type heat-shielding pavement conducted by the Japanese Civil Engineering Center. Irradiation experiments were carried out in a constant temperature and humidity conditions of 5RH%.

After 3 hours of irradiation, there was a rapid temperature change, but it showed a tendency to stabilize thereafter. When the temperature of the asphalt-based specimens rose to 65 ℃, the temperature-reducing effect of about -20 ℃ was shown on the asphalt specimen coated with heat-resistant anti-reflective paint. .

Measuring time Asphalt pavement Heat Resistant Reflective Paint 00:00 28.1 27.9 01:00 45.7 35.8 02:00 56.9 41.2 03:00 62.4 42.4 04:00 64.8 42.6 05:00 65 43.4 06:00 64.5 44.9 07:00 66.2 44.8 08:00 66.8 45.6 09:00 67.5 45.4 10:00 66.4 45 11:00 66.4 45.4 12:00 65.6 46.4

② cement concrete pavement

Test temperature 30 ± 1 ℃ Test humidity 50 ± by cement-based concrete test specimen and concrete specimen coated with heat-resistant antireflective paint Irradiation experiments were conducted at a constant temperature and humidity of 5RH%.

After 3 hours of irradiation, there was a rapid temperature change, but it showed a tendency to stabilize thereafter. When the temperature of the concrete standard specimen rose to 65 ℃, the temperature reduction effect of -15 ℃ was shown on the concrete specimen coated with the heat-reflective paint.

Measuring time Concrete pavement Heat Resistant Reflective Paint 00:00 27.4 28.2 01:00 41.6 36.8 02:00 54.2 42.3 03:00 59.1 45.4 04:00 63.7 46.7 05:00 64.9 47.2 06:00 66.3 48.4 07:00 66.4 50.6 08:00 66.0 50.6 09:00 65.9 50.2 10:00 66.4 50.4 11:00 65.9 50.7 12:00 66.4 50.2

③ Evaluation of thermal insulation performance by using bright pigment

This study was conducted to investigate the effect of heat reflecting heat shielding paint on the heat shielding effect of red and green color (L ^＊ : 39.7, a ^＊ : 33.4, b ^＊ : 24.7) L ^* : 40.3, a ^* : -31.1, b ^* : 21.2), and measured the color difference using a color difference meter.

Both the red and green heat shields showed a rapid change in temperature over three hours of irradiation, but no significant increase in temperature was observed after three hours. Compared with the asphalt specimen, when the surface temperature of the asphalt specimen increased to 70 ℃, the temperature reduction effect of about 15 ℃ was shown at 54.6 ℃ for the red heat shield paint and 55.5 ℃ for the green heat shield paint.

Measuring time Asphalt paving Heat Resistant Reflective Paint
(Red) Heat Resistant Reflective Paint
(green) 00:00 20.2 19.4 19.7 01:00 54.4 37.8 38.7 02:00 64.2 46.9 49.5 03:00 66 49.6 50.7 04:00 68.3 51.2 54.2 05:00 67.3 52.2 54.4 06:00 67.5 54.4 54.9 07:00 67.1 54 55.2 08:00 67.4 54.6 55 09:00 70.2 54.8 55.7 10:00 70.6 54.6 55.5

Second Embodiment

1. Reflection performance evaluation

Reflectance performance evaluation was based on the JIS K 5602: 2008 standard of Japan to measure the spectral reflectance to calculate the solar reflectance. The spectral reflectance refers to the reflectance obtained by the reflected light flux measured using a spectrophotometer with respect to the prescribed wavelength power in the wavelength range 300 to 2500 nm. The ratio of the reflected light beam from the coating film to the

 wavelength Spectral reflectance (%) Increment reflectance (%) Full wavelength range 84 88 Visible light wave
Long Area (320-780) 89 91 Infrared wavelength range (780 ~ 2500) 80 85

Wavelength λ (nm) Shielding coefficient (W / ㎡) Test wavelength λ (nm) Correction wavelength λ (nm) Spectral reflectance (%) Increment reflectance (%) 325 0.1083 325.26 325 95.24731016 10.31528369 330 0.1626 329.75 330 88.65296620 14.41497230 335 0.1989 335.67 335 91.05224225 18.11029098 340 0.2090 340.08 340 92.84412344 19.40442180 345 0.2214 344.46 345 94.45425543 20.91217215 350 0.2337 350.26 350 88.33924643 20.64488189 360 0.5085 360.32 360 81.67715186 41.53283172 370 0.6010 370.28 370 66.70769802 40.09132651 380 0.6983 380.16 380 54.10903546 37.78433946 390 0.7259 389.98 390 48.10515574 34.91953255 400 0.8782 399.76 400 55.63617574 48.85968953 410 1.0998 409.51 410 72.74029159 79.99977269 420 1.1863 420.63 420 89.01953739 105.6038772 430 1.1426 430.37 430 92.35316797 105.5227297 440 1.2024 440.11 440 93.11328584 111.9594149 450 1.4324 449.87 450 93.52843609 133.9701319 460 1.5831 459.65 460 93.39898466 147.8599326 470 1.6110 470.86 470 93.86114325 151.2103018 480 1.6255 480.70 480 94.16818647 153.0703871 490 1.6044 490.57 490 94.48111424 151.5854997 500 1.5640 500.48 500 94.49301221 147.7870711 510 1.5880 510.43 510 94.48143290 150.0365155 520 1.5557 520.42 520 94.75810688 147.4151869 530 1.5485 530.44 530 94.67268272 146.6006492 540 1.5819 540.49 540 94.62442768 149.6863821 550 1.5764 550.58 550 94.56746750 149.0761558 570 3.1029 570.86 570 94.36097656 292.7926742 590 2.9347 589.79 590 94.46587745 277.2290105 610 2.9183 610.28 610 94.46534789 275.6782247 630 2.9574 630.84 630 94.27850392 278.8192475 650 2.8911 650.00 650 94.41324937 272.9581453 670 2.8488 670.68 670 94.18886223 268.3252307 690 2.5551 689.92 690 94.01842404 240.2264753 710 2.4785 710.68 710 93.65233849 232.1173210 718 0.9429 718.11 718 93.48223715 88.14440141 724 0.6657 724.05 724 93.46140657 62.21725835 740 1.7813 740.40 740 93.21591119 166.0455026 753 1.5228 752.31 753 92.92861766 141.5116990 758 0.6001 756.78 758 92.87791051 55.73603410 763 0.4606 762.75 763 92.76763309 42.72877180 768 0.4239 767.22 768 92.63710204 39.26886755 780 1.3687 780.66 780 92.40293875 126.4719023 800 2.2415 800.12 800 92.20462589 206.6766689 816 1.5647 816.63 816 92.08744665 144.0892278 824 0.6374 824.15 824 92.01960438 58.65329583 832 0.6722 831.68 832 91.90013531 61.77527096 840 0.7078 840.74 840 91.74854242 64.93961832 860 1.9640 860.41 860 91.62467647 179.9508646 880 1.9370 880.17 880 91.35096709 176.9468233

Wavelength λ (nm) Shielding coefficient (W / ㎡) Test wavelength λ (nm) Correction wavelength λ (nm) Spectral reflectance (%) Increment reflectance (%) 905 2.1295 904.61 905 90.88162467 193.5324197 915 0.7172 915.35 915 90.49951937 64.90625529 925 0.6877 924.57 925 90.50793494 62.24230686 930 0.2770 930.72 930 90.44255353 25.05258733 937 0.2347 936.88 937 90.40368475 21.21774481 948 0.3186 947.68 948 90.35167259 28.78604289 965 0.7236 964.66 965 90.32258381 65.35742165 980 0.8914 980.11 980 90.42571378 80.60548126 994 0.9526 992.45 994 90.32729742 86.04578352 1040 3.3852 1044.11 1040 91.44379076 309.5555205 1070 2.0179 1075.73 1070 90.19182594 181.9980856 1100 1.5957 1106.40 1100 91.73151602 146.3759801 1120 0.5283 1116.41 1120 91.66571535 48.42699742 1130 0.1509 1126.33 1130 91.38570515 13.79010291 1137 0.1139 1136.15 1137 91.01195070 10.36626118 1161 0.5728 1165.02 1161 89.51276694 51.27291290 1180 0.7689 1183.79 1180 87.96710658 67.63790825 1200 0.8951 1202.21 1200 87.09158509 77.95567781 1235 1.6028 1238.01 1235 88.63687496 142.0671832 1290 2.4894 1289.29 1290 89.19857415 222.0509305 1320 1.0079 1322.00 1320 88.39987066 89.09822964 1350 0.4296 1353.65 1350 87.11738469 37.42562846 1395 0.0777 1391.84 1395 83.67396051 6.501466732 1443 0.1379 1443.10 1443 82.64809847 11.39717278 1477 0.1547 1478.37 1477 83.58650447 12.93083224 1497 0.2913 1499.09 1497 83.87454288 24.43265434 1520 0.5181 1519.53 1520 84.10817808 43.57644706 1539 0.5166 1539.72 1539 83.86922949 43.32684396 1558 0.5285 1559.70 1558 83.68968762 44.22999991 1592 0.3489 1592.65 1592 83.14827715 29.01043390 1610 0.4341 1612.27 1610 82.31443525 35.73269634 1630 0.4794 1631.83 1630 81.40899695 39.02747314 1646 0.3884 1644.85 1646 79.90699637 31.03587739 1678 0.7380 1677.45 1678 72.02225113 53.15242133 1740 1.2310 1743.40 1740 68.52227262 84.35091760 1800 0.6145 1797.69 1800 72.86116096 44.77318341 1860 0.0994 1861.42 1860 74.79747104 7.434868621 1920 0.0097 1922.48 1920 67.55933838 0.655325582 1960 0.0454 1958.08 1960 68.95571483 3.130589453 1985 0.1422 1981.47 1985 70.48925786 10.02357247 2005 0.1194 2004.59 2005 71.44479596 8.530508637 2035 0.1919 2038.77 2035 71.61281631 13.74249945 2065 0.2430 2061.21 2065 71.41988084 17.35503104 2100 0.2650 2105.29 2100 68.74239139 18.21673372 2148 0.4165 2148.29 2148 64.10174019 26.69837479 2198 0.3893 2200.51 2198 61.27520667 23.85443796 2270 0.5168 2270.77 2270 35.74454284 18.47277974 2360 0.6026 2356.24 2360 38.34072753 23.10412241 2499 0.0885 2494.64 2499 40.86894010 3.616901199

As described above, when the first coating layer 200 is applied to the concrete or asphalt concrete pavement surface 100 and then the second coating layer 200 is applied, the surface temperature of the road pavement body is reduced by about 7 to 15 ° C. It can be seen that the solar reflectance in the entire wavelength range is at least 70%.

100: packing cotton
200: primary coating layer
300: secondary coating layer

Claims (6)

Room temperature drying acrylic emulsion resin 30-50 wt%, glass beads 10-25 wt%, hollow ceramic 10-30 wt%, colored inorganic pigment 10-30 wt%, water 10-30 wt%, surfactant 1-5 wt% A heat-retardant reflective coating, obtained by mixing%, thickener 1 to 5% by weight, dispersant 1 to 3% by weight, and settling agent 1 to 3% by weight.
The method according to claim 1,
The glass beads,
Heat-reduction reflecting paint, characterized in that the glass having a refractive index of at least 2.2 or more of aluminum or metal having a thickness of 1 ~ 40㎛ coated by vacuum deposition.
The method according to claim 1,
The hollow ceramic,
Heat-resistant reflective paint, characterized by a density of 0.5-0.7 (g / cc), a particle size of 15 to 65 and a hollow ratio of 20 to 60% by volume.
The method according to claim 1,
Room temperature drying type acrylic emulsion resin (Acrylate emulsion resin),
Heat-resistant reflective coating, characterized in that consisting of a copolymer of methyl methacryl, methacrylic acid, acrylamide.
On road pavement,
Forming a primary coating layer by mixing a rheology alkyd resin and a binder using MDI as a curing agent and coating the film with 0.1-0.5 mm;
The road pavement method using the heat-reduced reflective paint, characterized in that by performing a secondary coating layer forming step of incorporating the heat-resistant low-reflective paint with silica sand on the upper surface after the first coating layer forming step to apply 0.1-3mm .
In the first coating layer forming step,
Road paving method using heat-resistant reflective paint, characterized by further mixing the water-retaining polymer resin.

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