JP2011117266A - Radiation heat transfer control film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiation heat transfer control film which, while maintaining a color tone of a base, can efficiently reflect energy of sunlight, thus can suppress heating of the base by the sunlight, and can reduce a cooling load, for example, in residential buildings and automobiles. <P>SOLUTION: First fine particles 12 having a predetermined particle diameter are distributed in a base material 11 transparent to visible light so as to scatter a near-infrared component of the sunlight. The first fine particles 12 are formed of one or a plurality of types of particles selected from among iron oxide (Fe<SB>2</SB>O<SB>3</SB>), iron pyrite (FeS<SB>2</SB>), chalcopyrite (CuFeS<SB>2</SB>), copper (I) oxide (Cu<SB>2</SB>O), copper (II) oxide (CuO), and metal particles having a diameter of 0.1 to 5 μm. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a radiation heat transfer control film.

  Reducing the cooling load on houses and factories contributes to global warming. When a white paint is applied to the exterior surface of a building to reduce the cooling load, energy absorption of sunlight can be reduced and indoor heating can be prevented. However, it is often undesirable to make the color of the roofing material white based on the appearance of a house, a building, or the like. In addition, dark-colored paint is often preferred for automobiles, but their outer walls not only absorb sunlight and make the interior of the vehicle at a high temperature when stopped, but also increase the cooling load while driving and reduce fuel consumption. I was invited.

  For this reason, conventionally, as a solar thermal barrier coating, a paint composed only of a color pigment having a solar reflectance of 13% or more (see, for example, Patent Document 1), and as shown in FIG. White pigment fine particles 51 of about 3 μm and pigment fine particles of about 1 μm in diameter are dispersed on a base 52 such as a roofing material or an outer wall.

Japanese Patent Laid-Open No. 2005-90042

However, the paint described in Patent Document 1 and the one in which a white pigment having a particle size of about 0.3 μm is dispersed reflect sunlight well, but it looks visually white. There was a problem of losing. In addition, a dispersion of a pigment having a particle size of about 1 μm is suitable for reflecting relatively long-wavelength infrared rays such as the infrared rays of incandescent bulbs, but the reflection characteristics of near-infrared components of sunlight are not good. There was a problem. Further, in the case where the fine particles 51 are directly dispersed on the colored substrate 52, since all the wavelength components of sunlight are absorbed by the pigment contained in the substrate 52, the reflection efficiency by the fine particles is reduced and the radiation heating is increased. There was also a problem to do.
In addition, the ultraviolet rays contained in sunlight often degrade organic materials such as plastics and reduce strength.

  The present invention has been made by paying attention to such problems, and while maintaining the color tone of the base, it can efficiently reflect the energy of sunlight and suppress the heating of the base by sunlight. An object of the present invention is to provide a radiation heat transfer control film capable of reducing a cooling load of an automobile or the like.

In order to achieve the above object, a radiation heat transfer control film according to the present invention comprises a base material transparent to visible light and a predetermined distributed in the base material so as to be able to scatter near infrared components of sunlight. First fine particles having a particle size, wherein the first fine particles are iron oxide (Fe ₂ O ₃ ), pyrite (FeS ₂ ), chalcopyrite (CuFeS ₂ ), copper oxide (I) (Cu ₂ O). , Copper (II) (CuO), or metal particles having a particle size of 0.1 to 5 μm.

  The radiant heat transfer control film according to the present invention is mainly provided on a base material such as a roofing material or outer wall of a house, or a car body of an automobile. Since the base material of the radiation heat transfer control film according to the present invention is transparent to visible light, the color tone of the base can be maintained. Moreover, since the near-infrared component which occupies about 40% of the energy amount of sunlight can be scattered by the 1st fine particle distributed in the base material, a near-infrared energy is reflected efficiently and the board | substrate is heated by sunlight. Can be suppressed. Thereby, the cooling load of a house, a car, or the like can be reduced and the cooling efficiency can be increased during periods of strong solar radiation such as summer. In the case of automobiles, fuel consumption is expected to improve due to a reduction in cooling load in summer. In addition, the near infrared ray of sunlight has a wavelength of about 0.7 to about 2.5 μm. Visible light has a wavelength of about 0.36 to about 0.7 μm.

  The substrate may be any material as long as it is transparent to visible light, and may be made of, for example, plastic or glass. The first fine particles preferably have a small scattering effect on visible light components and long-wavelength infrared rays having a wavelength of about 10 μm. In this case, while reflecting the near-infrared component of sunlight, it is possible to maintain the color even if the base is dark, such as black or gray, and maintain the color tone of the base by suppressing visible light reflection. Excellent effect. Moreover, since the radiation cooling of the substrate is not hindered, the substrate is also excellent in heating suppression effect. The radiation heat transfer control film according to the present invention may be formed by coating a base material with a paint in which first fine particles are distributed in a solvent. In this case, the same effect can be obtained by coating with a conventional paint of each color and coating the coating film.

In the radiation heat transfer control film according to the present invention, the first fine particles may include iron oxide (Fe ₂ O ₃ ) particles having a particle size of 0.03 to 0.06 μm or 0.5 to 5 μm, It may contain pyrite (FeS ₂ ) or chalcopyrite (CuFeS ₂ ) particles having a particle size of 0.07 to 0.08 μm or 0.3 to 0.6 μm, and copper oxide having a particle size of 0.1 to 10 μm (I) (Cu ₂ O) particles may be included, and copper oxide (II) (CuO) particles having a particle diameter of 0.05 to 10 μm may be included. In particular, when copper oxide (I) (Cu ₂ O) particles are included, the particle diameter is 0.2 to 3 μm, and when copper oxide (II) (CuO) particles are included, the particle diameter is 0.1 to 5 μm. Preferably there is. In these cases, the effect of maintaining the color tone of the base and the heating suppression effect of the base are particularly excellent.

  Furthermore, in the radiation heat transfer control film according to the present invention, the first fine particles may include metal particles made of copper, gold, silver, aluminum, or nickel having a particle size of 0.1 to 5 μm. In particular, the metal particles preferably have a particle size of 0.2 to 5.0 μm. Moreover, when a metal particle is copper or gold | metal | money, it is preferable that a particle size is 0.2-3 micrometers. In these cases, the effect of maintaining the color tone of the base and the heating suppression effect of the base are particularly excellent.

  The radiation heat transfer control film according to the present invention has second fine particles having a predetermined particle diameter or bubbles having a predetermined diameter distributed in the substrate so as to be able to scatter ultraviolet components of sunlight. Also good. In this case, since the ultraviolet component of sunlight can be scattered by the second fine particles or bubbles, it is possible to efficiently reflect the ultraviolet energy and prevent the plastic substrate or the like from being altered by the ultraviolet rays. As a result, it is possible to prevent the base from being deteriorated and the strength from being lowered, and the life of the base can be extended. In this way, by using the first fine particles and the second fine particles or bubbles in combination, it is possible to obtain an effect of preventing deterioration of the substrate simultaneously with an effect of suppressing the heating of the substrate. In addition, the ultraviolet rays of sunlight have a wavelength of about 0.001 to about 0.36 μm and occupy about 5% of the energy amount of sunlight.

  The second fine particles and bubbles preferably have a small scattering effect on visible light components and long-wavelength infrared rays having a wavelength of about 10 μm. In this case, the effect of suppressing visible light reflection and maintaining the color tone of the substrate is excellent, and since the radiation cooling of the substrate is not inhibited, the heating suppression effect of the substrate can be enhanced. The second fine particles are titanium oxide having a particle size of 0.06 to 0.10 μm, alumina having a particle size of 0.6 to 1.0 μm, zirconia having a particle size of 0.06 to 0.3 μm, or a particle size of It is composed of metal particles of 0.01 to 0.2 μm, and the bubbles preferably have a diameter of 0.05 to 0.2 μm. In this case, the effect of preventing deterioration of the base is particularly excellent.

  ADVANTAGE OF THE INVENTION According to this invention, while maintaining the color tone of a board | substrate, the energy of sunlight can be reflected efficiently, the heating of the board | substrate by sunlight can be suppressed, and the cooling load of a house, a motor vehicle, etc. can be reduced. A radiation heat transfer control film can be provided. In particular, in the case of automobiles, dark paint is often preferred, but according to the present invention, fuel efficiency is expected to be improved by reducing the cooling load in summer while maintaining the blackish color of the paint. Further, by mixing the second fine particles or bubbles, it is possible to reduce the ultraviolet deterioration of the substrate and prevent the substrate from being discolored, the substrate material from being altered or cracked.

It is sectional drawing which shows the radiation heat-transfer control film | membrane of the 1st Embodiment of this invention. It is a graph which shows the particle size change of the optimization parameter of the iron oxide particle which comprises the 1st microparticles | fine-particles of the radiation heat transfer control film | membrane shown in FIG. It is a graph which shows the particle size dependence of the optimization parameter of the pyrite particle which comprises the 1st microparticles | fine-particles of the radiation heat transfer control film | membrane shown in FIG. It is a graph which shows the particle size dependence of the optimization parameter of the coating film which suspended the metal particle which comprises the 1st microparticles | fine-particles of the radiation heat transfer control film | membrane shown in FIG. It is a graph which shows the particle size dependence of the optimization parameter of the copper (II) oxide particle which comprises the 1st microparticles | fine-particles of the radiation heat transfer control film | membrane shown in FIG. It is a graph which shows the particle size dependence of the optimization parameter of the copper (I) oxide particle which comprises the 1st microparticles | fine-particles of the radiation heat transfer control film | membrane shown in FIG. It is a graph which shows the reflectance with respect to a wavelength when the copper (II) oxide particle | grains of optimal particle diameter dp _{, opt} = 0.57micrometer are used as 1st microparticles | fine-particles of the radiation heat transfer control film _| membrane shown in FIG. Optimization parameter R and film thickness parameter b when titanium oxide (TiO ₂ ), alumina (Al ₂ O ₃ ), and zinc oxide (ZnO) having _{an optimum} particle diameter (d _{p, optimum} ) are used as the first fine particles It is a graph which shows the relationship. It is sectional drawing which shows the base | substrate which disperse | distributed the conventional fine particle.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 8 show a radiation heat transfer control film according to an embodiment of the present invention.
As shown in FIG. 1, the radiation heat transfer control film 10 includes a base material 11, first fine particles 12, and second fine particles 13. The radiation heat transfer control film 10 is provided on a base 1 such as a roofing material or outer wall of a house or a coating film of an automobile.

  The base material 11 is transparent to visible light. The substrate 11 is made of, for example, plastic, glass, or transparent paint that is transparent to visible light. The base material 11 is formed with a thickness of about 10 μm to 1 mm so as not to block long-wavelength infrared light having a wavelength of about 10 μm emitted from the substrate 1. In addition, when the base material 11 consists of glass, the thickness of about 1 micrometer may be sufficient.

The first fine particles 12 are, for example, iron oxide (Fe ₂ O ₃ ), pyrite (FeS ₂ ), chalcopyrite (CuFeS ₂ ), copper oxide (I) (Cu ₂ O), copper oxide each having a predetermined particle size. (II) (CuO) or one or a plurality of metal particles having a particle diameter of 0.1 to 5 μm. The first fine particles 12 are distributed in the base material 11 at a predetermined particle density so that the near-infrared component of sunlight can be scattered. The first fine particles 12 have a small scattering effect on visible light components and long-wavelength infrared rays having a wavelength of about 10 μm.

  The second fine particles 13 are made of, for example, titanium oxide, alumina, zirconia, or metal particles each having a predetermined particle size. The second fine particles 13 are distributed in the base material 11 at a predetermined particle density so as to be able to scatter ultraviolet components of sunlight. The second fine particles 13 have a small scattering effect on visible light components and long-wavelength infrared rays having a wavelength of about 10 μm. Instead of the second fine particles 13, bubbles having a predetermined diameter capable of scattering the ultraviolet component of sunlight may be distributed in the substrate 11.

The base 1 is made of a colored base such as black.
The radiant heat transfer control film 10 may be formed of a coating film formed by coating the base 1 with a paint in which the first fine particles 12 and the second fine particles 13 are suspended in a solvent.

Next, the operation will be described.
The radiation heat transfer control film 10 maintains the color tone of the substrate 1 because the substrate 11 is transparent to visible light, and the first fine particles 12 and the second fine particles 13 both have a small visible light scattering effect. Can do. Moreover, since the near-infrared component which occupies about 40% of the energy amount of sunlight can be scattered with the 1st microparticles | fine-particles 12 distributed in the base material 11, a near-infrared energy is reflected efficiently and the foundation | substrate by sunlight 1 heating can be suppressed. Thereby, the cooling load of a house, a car, or the like can be reduced and the cooling efficiency can be increased during periods of strong solar radiation such as summer. In the case of automobiles, fuel consumption is expected to improve due to a reduction in cooling load in summer.

In order to quantitatively evaluate this effect, an optimization parameter R is introduced.
Here, ρ _VIS is the reflectance of visible light, and ρ _NIR is the reflectance of near-infrared light. The larger the optimization parameter R, the darker the visual appearance and the reflection of near-infrared light. The effect is high.

  FIG. 2 shows an optimization parameter R when iron oxide is used as the first fine particles 12. The optimization parameter differs depending on the film thickness parameter b = (particle volume fraction fv) × (coating thickness t), but generally, as shown in FIG. It turns out that an effect is high when it adjusts so that a diameter may be set to 0.03-0.06 micrometer or 0.5-5 micrometers. The reflectance of visible light is small at 0.03 to 0.06 μm, and the reflectance of visible light slightly increases at 0.5 to 5 μm, but it is a region where the reflectance of near infrared light is high. When titanium oxide is used, the optimization parameter R is 4.3 at the maximum, and the effect is greater when iron oxide is used.

  FIG. 3 shows an optimization parameter R when pyrite is used as the first fine particles 12. As shown in FIG. 3, the optimum value is a particle size of 0.07 to 0.08 μm or 0.3 to 0.6 μm. Also in this case, it can be seen that the heat shielding effect is larger than that of iron oxide. In addition, iron oxide is slightly reddish in color, while pyrite is close to black. By mixing optimized pyrite particles in iron oxide, it is darker while maintaining thermal insulation performance. It is possible to adjust to the color. For this reason, it is effective when used for an automobile or the like in which dark-colored coating is preferred. In addition, chalcopyrite has the same effect as pyrite steel.

  FIG. 4 shows changes in the optimization parameter R when the metal fine particles are suspended in the solvent that forms the radiation heat transfer control film 10 made of a coating film. As shown in FIG. 4, it can be seen that the optimization parameters are large for metal particles such as copper, gold, silver, aluminum and nickel having a particle size of 0.1 to 5 μm, of which the particle size is 0.2 to 5 μm. . In particular, the heat shielding performance of the copper and gold fine particle suspension is high, and the best heat shielding performance is obtained when the particle diameter is 0.2 to 3 μm.

  5 and 6 show the optimization parameter R when the copper (II) oxide particles and the copper (I) particles are suspended in the solvent for forming the radiation heat transfer control film 10 made of a coating film, respectively. It shows a change. As shown in FIGS. 5 and 6, the optimum values are a particle size of 0.05 to 10 μm for copper (II) oxide and a particle size of 0.1 to 10 μm for copper (I) oxide. In particular, in the case of copper oxide (II), the particle size is 0.1 to 5 μm, and in the case of copper oxide (I), the optimization parameter value is extremely high when the particle size is 0.2 to 3 μm. Is obtained.

FIG. 7 shows the reflectance of the radiation heat transfer control film 10 with respect to the wavelength when copper (II) oxide having an optimum particle diameter d _{p, opt} = 0.57 μm is used as the first fine particles 12. As shown in FIG. 7, when copper (II) oxide is used, a black coating film is obtained because the reflectance in the visible region (VIS) is lower and uniform than in the near infrared region (NIR). For this reason, it is effective when maintaining the blackish color of the coating of the board | substrate 1 like the painting of a motor vehicle. On the other hand, iron oxide and copper oxide (I) have a large optimization parameter R, but are red, and may not be suitable depending on the color of the substrate 1.

Table 1 shows the film thickness parameters (b), the optimum particle diameter (d _{p, opt} ), the visible light reflectance (ρ _VIS ), and the near infrared light reflectance (ρ _NIR ) as the first fine particles 12 of various particles and bubbles. ), Total reflectance (TSR), optimization parameter (R), and brightness (Y) as an index of brightness.

As shown in Table 1, iron oxide (Fe ₂ O ₃ ), copper oxide (II) (CuO), pyrite (FeS ₂ ), copper oxide (I) (Cu ₂ O), copper (Cu) and gold (Au ) Shows that the visible light reflectance is small, the near-infrared light reflectance and the optimization parameter are large, and the effect of maintaining the color tone of the substrate 1 and the heat shielding effect are high. Compared to the case of titanium oxide (TiO ₂ ) particles, these particles have significantly improved heat shielding performance and low reflectance of the coating film against visible light. In particular, since copper (II) oxide is black and has a large optimization parameter, it is effective in maintaining the blackish color of the base 1 paint, such as automobile paint.

  According to the color analysis of the coating film, the fine particles of iron oxide, copper (I) oxide, copper, and gold have a slightly reddish color tone. Therefore, by mixing optimized pyrite, chalcopyrite, or copper (II) oxide fine particles into fine particles of iron oxide, copper (I) oxide, copper, and gold, heat shielding performance while making the color of the coating film darker Can be improved.

In addition, as shown in Table 1, the first fine particles 12 are iron oxide (Fe ₂ O ₃ ), copper oxide (II) (CuO), pyrite (FeS ₂ ), copper oxide (I) (Cu ₂ O), copper Unlike the case of titanium oxide (TiO ₂ ), alumina (Al ₂ O ₃ ), or zinc oxide (ZnO) shown in FIG. 8, the optimization parameter R is the maximum when it is made of (Cu) or gold (Au). The film thickness parameter b is large. This is because of the fine particles of iron oxide (Fe ₂ O ₃ ), copper oxide (II) (CuO), pyrite (FeS ₂ ), copper oxide (I) (Cu ₂ O), copper (Cu) or gold (Au). It shows that the optimization parameter R increases as the mixing amount increases, that is, as the coating film becomes thicker.

Therefore, as the first fine particles 12, iron oxide (Fe ₂ O ₃ ), copper (II) oxide (CuO), pyrite (FeS ₂ ), copper oxide (I) (Cu ₂ O), copper (Cu) or gold When (Au) is used, if the coating film is thickened, the heat shielding effect can be enhanced. However, it is necessary to set an appropriate thickness of the substrate 11 (coating film) so as not to impair the color of the substrate 1. is there.

  Since the radiation heat transfer control film 10 can scatter the ultraviolet component of sunlight by the second fine particles 13, it efficiently reflects the ultraviolet energy and prevents the plastic substrate 1 or the like from being altered by the ultraviolet rays. Can do. In addition, deterioration of the coating film due to ultraviolet rays can be suppressed. Thereby, discoloration of the coating film, deterioration of the base 1, deterioration such as cracks, and strength reduction can be prevented, and the life of the base 1 can be extended. As described above, the radiation heat transfer control film 10 can obtain the effect of preventing deterioration of the substrate 1 as well as the effect of suppressing the heating of the substrate 1 by using the first particles 12 and the second particles 13 together.

  As the second fine particles 13, titanium oxide having a particle size of 0.06 to 0.10 μm, alumina having a particle size of 0.6 to 1.0 μm, zirconia having a particle size of 0.06 to 0.3 μm, or particle size By using metal particles having a thickness of 0.01 to 0.2 μm, an excellent base material alteration preventing effect can be obtained. Further, when bubbles are used in place of the second fine particles 13, when the diameter of the bubbles is 0.05 to 0.2 μm, an excellent effect of preventing deterioration of the base can be obtained.

  In the radiation heat transfer control film 10, the base material 11, the first fine particles 12, and the second fine particles 13 have a small scattering effect on long-wavelength infrared light having a wavelength of about 10 μm, and do not hinder heat radiation from the substrate 1 due to long-wavelength radiation. For this reason, it is possible to further enhance the effect of suppressing heating by sunlight and the effect of reducing the cooling load.

  The radiation heat transfer control film 10 has a sufficient particle size and particle density for the first fine particles 12 and the second fine particles 13 for visible light and long-wavelength infrared rays while reflecting the near-infrared rays and ultraviolet rays of sunlight well. By controlling so as to have excellent permeability, it is possible to obtain an excellent heating suppression effect of the substrate 1 and an alteration preventing effect of the substrate 1 while maintaining the color tone of the substrate 1.

  When the radiation heat transfer control film 10 is used for a ceramic substrate 1 such as a roof tile or an exterior tile, the first fine particles 12 and the second fine particles 13 having an optimized particle size and particle density are mixed into the glaze. By firing, the same effect can be obtained. Moreover, the same effect can also be acquired by disperse | distributing the 1st microparticles | fine-particles 12 and the 2nd microparticles | fine-particles 13 which optimized the particle size and particle | grain density to the transparent coating material, and apply | coat to the base | substrate 1 by fixed thickness. A similar effect can be obtained by fusing or adhering a plastic film in which the first fine particles 12 and the second fine particles 13 with optimized particle diameter and particle density are dispersed on the substrate 1.

The radiation heat transfer control film according to the present invention is a fiber glass reinforced plastic exterior plate or roofing material, an outer plate material such as a concrete or ceramic tile roofing material, a general building material, etc., or a heating of an automobile. It can be applied to various fields such as prevention.
In addition, the radiation heat transfer control film according to the present invention can be widely used as a heat-preventing paint or coating agent from sunlight, a coating agent, an agent for preventing deterioration of plastic due to ultraviolet rays.

1 Base 10 Radiation Heat Transfer Control Film 11 Base Material 12 First Fine Particle 13 Second Fine Particle

Claims (7)

A substrate transparent to visible light;
The first fine particles having a predetermined particle size distributed in the base material so as to be able to scatter the near infrared component of sunlight,
The first fine particles include iron oxide (Fe ₂ O ₃ ), pyrite (FeS ₂ ), chalcopyrite (CuFeS ₂ ), copper oxide (I) (Cu ₂ O), copper oxide (II) (CuO), or Consisting of one or more of metal particles having a particle size of 0.1-5 μm,
Characteristic radiation heat transfer control film. _2. The radiation heat transfer control film according to claim 1, wherein the first fine particles include iron oxide (Fe ₂ O ₃ ) particles having a particle diameter of 0.03 to 0.06 μm or 0.5 to 5 μm. . The first fine particles include pyrite (FeS ₂ ) or chalcopyrite (CuFeS ₂ ) particles having a particle size of 0.07 to 0.08 μm or 0.3 to 0.6 μm. 2. The radiation heat transfer control film according to 2. 4. The radiation heat transfer control film according to claim 1, wherein the first fine particles include copper (I) (Cu ₂ O) particles having a particle diameter of 0.1 to 10 μm.   5. The radiation heat transfer control film according to claim 1, wherein the first fine particles include copper (II) oxide (CuO) particles having a particle diameter of 0.05 to 10 μm.   6. The radiation according to claim 1, 2, 3, 4 or 5, wherein the first fine particles include metal particles made of copper, gold, silver, aluminum or nickel having a particle diameter of 0.1 to 5 [mu] m. Heat transfer control membrane. The second fine particles having a predetermined particle diameter distributed in the base material or bubbles having a predetermined diameter are provided so as to be able to scatter ultraviolet components of sunlight. 5. The radiation heat transfer control film according to 5 or 6.