JP2001262072A - Light and heat-proofing coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new coating material which displays the light and heat- proofing and heat-insulating effects in the summer by coating the outside surface of open-air buildings, storage tanks, transporting containers, food grain silos and so on. SOLUTION: The light and heat-proofing covering material to form a flat coating film after the coating and thus to reflect efficiently the heat energy wave region of the sunlight, comprises a sunlight-reflecting ceramic filler which has been sintered at a high temperature and pulverized into microparticles having a particle diameter of 0.2-0.5 μm, and a water-soluble, chemically reacted resin. The light and heat-proofing covering material invented exhibits a heat insulating effect toward the inside by keeping a surface temperature on the covering material to a state near the atmospheric temperature. Combinations of undercoating materials form the coating films excellent in the adhesion, rust-proofness and flatness, thus making it possible to maintain the result during a long term.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0101]

TECHNICAL FIELD The present invention prevents an increase in the internal temperature due to direct sunlight by painting the outer surfaces of outdoor buildings, storage tanks, transport containers, grain storage silos, etc.
The present invention relates to a light-shielding heat coating material capable of saving energy of electric power in cooling and freezing, and preventing a temperature rise of dangerous substances such as LP gas and petroleum and grain.

[0092]

2. Description of the Related Art In recent years, the rise in internal temperature due to sunlight has been prevented, and the amount of electricity consumed during the summer in factories and buildings has been reduced to reduce utility costs. It is required to suppress the temperature rise of the dangerous goods themselves. In order to deal with such problems, measures that have been conventionally applied include a method in which a paint containing aluminum powder is applied to the roof or the outer surface of a storage tank, and ceramics, glass powder, and an air layer having a large specific heat. There is a method to apply roof paint on the roof and roof.

[0093]

The method of applying a paint containing aluminum powder to a roof or an outer surface of a tank, which has been conventionally used, has a low reflection efficiency in a heat energy wavelength region of sunlight of aluminum powder, and the aluminum has a low efficiency. Since heat is transferred to the powder itself, the surface temperature of the coating film reaches 60 ° C. or higher during the daytime in summer.

Further, a method of applying a paint containing a ceramic, glass powder, or an air layer having a large specific heat to a roof or a roof portion uses a ceramic or a glass powder having a very large particle size. Finished state is not smooth,
Irregularities are created. For this reason, there is a drawback that dirt is easily formed, which leads to an increase in the temperature of the coating film surface, and the temperature reduction effect is lost. In paints containing this ceramic or glass powder,
Although a method of further topcoating has been put into practical use for the purpose of preventing contamination, the cost is increased due to an increase in man-hours and the like.

[0056]

Means for Solving the Problems Sunlight is composed of ultraviolet light, visible light, and near-infrared light, the total energy of which is 700 kcal / m ² · h. %, The visible light region is 44.3%, and the near infrared region is 53.0%. The present inventors have made intensive studies to solve the above problems, and as a result, efficiently reflect the heat energy wavelength range of sunlight of 0.2 to 2.5 μm including ultraviolet rays, visible rays, and near infrared rays. The solar reflective ceramic filler was selected, and the resin used for the overcoating material and the undercoating material was selected from among environmentally friendly water-soluble chemically-reactive resins that have extremely low solvent volatilization. Furthermore,
The water-soluble chemically reactive resin used for the overcoat material is difficult to transmit heat energy to the inside, and is effective in dissipating heat energy, and is excellent in smoothness. On the other hand, it is used for the undercoat material. The water-soluble chemically reactive resin uses a resin that has excellent adhesion to the base material, and furthermore, by using a solar ceramic filler having a particle size of 1 μm or less, a light-shielding film having a smooth coating film that is hardly stained can be obtained. The knowledge that a thermal coating material can be obtained has led to the present invention. Hereinafter, the present invention will be described in detail.

The thermal energy wavelength range of sunlight is 0.2
Since the solar reflective ceramic filler has a function of efficiently reflecting this wavelength range, it is sintered at high temperature and finely divided,
It is preferable that the refractive index is discontinuous at an interface such as a grain boundary and the particle size at which sunlight is easily disturbed is 1 μm or less. The most effective particle size for disturbing sunlight and suppressing absorption as much as possible is about 1/2 of the thermal energy wavelength of sunlight.
Particle sizes in the range of 0.5 μm are particularly desirable. A mixture of at least two or more selected from the group consisting of titanium oxide, magnesium oxide, silicon oxide, zinc oxide, and alumina as those satisfying such performance. It is most preferable that the particles have a particle size in the range of 0.2 to 0.5 μm. When the particle size of the solar reflective ceramic filler is within the above range, a uniform coating surface can be obtained after coating by uniformly dispersing the filler in the water-soluble chemically reactive resin.

The chemical reaction resin used in the light-shielding thermal top coating material of the present invention has a very low solvent volatilization and is an environmentally friendly water-soluble chemical reaction resin. And the water-soluble chemically reactive resin itself is less likely to absorb the wavelengths of sunlight's thermal energy wavelength range. Is preferably small. Water-soluble chemically reactive resins satisfying such performance include silicone resins having no urethane bond, acrylic silicone resins,
It is preferably at least one or more selected from the group consisting of acrylic resins.

The chemically reactive resin used in the light-shielding heat undercoat material of the present invention has a very low solvent volatilization and is an environmentally friendly water-soluble chemically reactive resin. It is preferable that a material which is applied to the base material to exhibit the adhesion to the base material, the rust-preventing effect, and the sunlight reflection function by coating. The water-soluble chemically reactive resin satisfying such properties is at least one selected from the group consisting of silicone resin, acrylic silicone resin, acrylic resin, epoxy resin, urethane resin, polyester resin, and alkyd resin. Is preferred.

The compounding amount of the solar reflective ceramic filler and the water-soluble chemically reactive resin is 100% by weight of the solid content of the chemically reactive resin and 20 to 20 of the solar reflective ceramic filler.
0% by weight is preferred. When the amount of the solar reflective ceramic filler is less than 20%, the heat energy reflecting performance of sunlight is lacking, and when it exceeds 200%, physical properties such as adhesion and impact resistance when formed into a film are deteriorated.

The light-shielding heat-coating material constituted as described above may contain a rust preventive pigment, an extender pigment, a dispersant, a viscosity improver,
A surface smoothing agent, an anti-settling agent, an ultraviolet absorber, a color separation inhibitor and the like can be used. It is also possible to arbitrarily mix various organic and inorganic pigments as colorants. However, it is not basically added because the sunlight reflectance in the visible light region is reduced.

[0111]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples. In addition, the composition values described in Examples and Comparative Examples all indicate weight or weight%. (Example 1) To 100 parts of an acrylic resin solution (Dianal LX-103, solid content 35%, manufactured by Mitsubishi Rayon Co., Ltd.)
Solar reflective ceramic filler (composition titanium oxide 9
35 parts (0%, magnesium oxide 5%, silicon oxide 3%, alumina 2%) are mixed and dispersed to prepare a dispersion solution. This dispersion solution is coated on a galvanized sheet (thickness 0.8 mm, diameter 290 m).
m) was coated so that the coating film thickness became 70 μm, and dried and cured at room temperature for 1 week to prepare a sample. (Comparative Example 1) A sample similar to that of Example 1 was prepared using a reflective paint containing aluminum powder (Hi-Alma (silver) manufactured by Daido Paint Co., Ltd.). However, the coating thickness was 180 μm as specified. (Comparative Example 2) A sample similar to that of Example 1 was prepared using a ceramic-containing heat-insulating paint (Super Therm, manufactured by Superior Products). However, the coating thickness was 220 μm as specified. Table 1 shows the solar absorptivity of the paint films of the samples prepared in Example 1 and Comparative Examples 1 and 2. Each of the prepared samples was placed in a constant-temperature room at an ambient temperature of 30 ° C. in the acrylic apparatus shown in FIG. 2 with the painted surface facing upward, and the painted surface was irradiated with an infrared lamp. Was measured. Table 2 shows the results.

[Table 1]

[Table 2]

Example 2 100 parts of an epoxy resin solution (Allon 21 solid content 37%, manufactured by Nippon Shokubai Co., Ltd.) was mixed with a solar reflective ceramic filler (composition 90% titanium oxide,
(Magnesium oxide 5%, silicon oxide 3%, alumina 2%)
20 parts and 10 parts of a rust preventive pigment (Zinchua No. 1 manufactured by Sakai Chemical Co., Ltd.) are mixed and dispersed to prepare a dispersion solution. This dispersion solution was applied to a dull steel plate (0.8 mm in thickness) so that the coating thickness became 30 μm, dried at room temperature for one day, and then the dispersion solution prepared in Example 1 was further coated with a coating thickness of 70 μm. Painted to become
The sample was dried and cured for one week to prepare a sample. (Comparative Example 3) The dispersion solution prepared in Example 1 was directly applied to a dull steel plate (0.8 mm thick) so that the coating thickness became 70 µm, and dried and cured for one week to prepare a sample. (Comparative Example 4) A sample was prepared in the same manner as in Comparative Example 3 using an aqueous acrylic silicone paint (Silicomax (white) solid content 54%, manufactured by Rock Paint Co., Ltd.). The adhesion of the samples prepared in Example 2, Comparative Example 3 and Comparative Example 4 was confirmed, and the results of salt spray test as a test of rust resistance are shown in Table 3. In addition, JIS was used as the adhesion evaluation test.
After cutting 1 mm square according to the K5400 6-15 cross cut test, the state of the coating film was determined by peeling off Cellotape (registered trademark). The rust resistance test was performed by conducting a JIS K5400 7-8 salt spray test for 300 hours to determine the state of the coating film.

[Table 1]

[Table 2]

The light-shielding heat-coating material of the present invention has a coating surface which is smooth and hard to be stained, has the ability to reflect the heat energy of sunlight, and keeps the surface temperature of the coating film close to the outside temperature. Has characteristics. Therefore, by applying this light-shielding thermal coating material to the rooftop and outer wall of the building, the rise in internal temperature is prevented,
Utility costs such as cooling can be reduced. Further, since the surface of the coating film is smooth, the light-shielding heat effect can be maintained for a long period of time without causing contamination. Further, since the undercoating material has sunlight reflection performance, and is a paint excellent in adhesion and rust prevention, the undercoating material exerts an effect for maintaining the coating film for a long period of time and greatly contributes to industrial development.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a method of testing the heat-shielding heat resistance of Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Infrared lamp 2 ... Coating material 3 ... Tin plate 4 ... Temperature measurement point 5 ... Acrylic resin container

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09D 5/00 C09D 5/00 A 7/12 7/12 Z 133/00 133/00 183/04 183 / 04 F term (reference) 4D075 AE03 CA18 CB04 DA06 DB01 DC05 EA02 EA06 EB22 EB42 EC02 EC15 EC53 4J038 CG141 CJ291 CQ001 DB001 DD001 DD121 DG001 DL031 DL131 HA186 HA216 HA446 HA566 KA08 KA12 KA20 MA08 MA09 NA01 NA03 NA03

Claims (5)

[Claims] 1. A thermal energy wavelength region of sunlight of 0.2 to 0.2.
A light-shielding thermal topcoat material comprising a solar reflective ceramic filler having a performance of efficiently reflecting 2.5 μm as a main component, and a binder of a water-soluble chemically reactive resin solution having a property of a small thermal conductivity and a small specific heat. 2. The light-shielding thermal top-coating material contains a fine-particle solar ceramic filler as a main component,
The light-shielding thermal coating material according to claim 1, wherein the coating film is finished smoothly after coating. 3. The thermal conductivity of the water-soluble chemically reactive resin containing no urethane bond is 4 to 6 × 10 ⁻⁴ cal / cm ·.
A silicone resin having a specific heat of 0.2 to 0.4 sec / C, a thermal conductivity of 3 to 6 × 10 ⁻⁴ cal / cm · sec · ° C., an acrylic silicone resin having a specific heat of 0.2 to 0.4, a thermal conductivity 3-5 × 10 ⁻⁴ cal / cm · sec · ° C., specific heat 0.
3. The method according to claim 1, wherein said at least one resin is selected from the group consisting of 2 to 0.3 acrylic resins.
The light-shielding thermal coating material according to 1. 4. A water-soluble chemically reactive resin solution containing a sun-reflecting ceramic filler as a main component and further supplementally containing a rust-preventive pigment and the like, and having good adhesion to a base material and excellent in rust-prevention properties, and Light-shielding thermal primer. 5. A high-temperature solar reflective ceramic filler comprising a mixture of at least two or more selected from the group consisting of titanium oxide, magnesium oxide, silicon oxide, zinc oxide, and alumina, and having a particle size of 1 μm or less. 5. The light-shielding thermal coating material according to claim 1, which is sintered and finely divided.