JPS5942627B2 - Radiation heat shielding transparent sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radiant heat shielding transparent sheet, and more specifically, it is capable of suppressing the transmission of visible light as well as infrared rays (heat rays) among the light rays associated with sunlight, and is suitable for use on windows of automobiles, buildings, etc. The present invention relates to a radiant heat shielding transparent sheet that, when attached to glass, can suppress the rise in temperature inside a car, especially in the summer.

Here, the term "sheet" includes a film-like material.

In addition, although the case where the present invention is applied to an automobile window glass will be described below as an example, the present invention is not limited to this. In order to prevent the temperature inside the company from rising during the summer, a four-colored transparent acrylic resin board or one containing aluminum foil is attached to the rear window.

Another method was to apply paint directly to the rear window and color it. However, although these methods can block visible light to some extent, they can hardly block heat rays, and their effectiveness in preventing temperature rise inside the vehicle is small.

That is, as shown in Figure 1 and the attached table, in both the case of 4 (dotted chain line; conventional example 1) and the case of @ (dotted line; conventional example 2), the transmittance in the hot ray region (700X or more) is 80~ 90
%, and therefore the radiant heat transmittance is also 60 to 70.
%, and the effect of preventing temperature rise inside the car is small.

In addition, in the case of @, the total light transmittance in the visible range is 5%.
Because of its small size, if it was applied to the rear window of the vehicle in front, the so-called forward visibility, which allows the vehicle behind to see through the vehicle in front, would be extremely poor.Furthermore, it required skill to paint. In addition, here, the test pieces of conventional examples 1 and 2 in FIG. 1 and the attached table are blue acrylic plates (
3) containing aluminum foil, transparent acrylic board (
3) with one side coated with indigo paint was used.

In addition, the transmittance of radiant heat was determined by placing a color photographic light (color temperature: 5500) 1 at the position 450- of the test piece (sheet) 2, as shown in Figure 2, and using a Robitsch pyranometer. 3 to 150 below test piece 2! lr! It was placed at position n and measured. In view of the above, this invention can suppress the transmission of infrared rays (heat rays) as well as visible light among the light rays accompanying sunlight, and can suppress the transmission of radiant heat while ensuring a certain degree of forward visibility. The purpose is to provide a radiant heat shielding transparent sheet. The gist of this invention is to form a metal vapor deposition film of 20 to 120λ using transition metals such as chromium or nickel, or alloys containing these, on the surface of a transparent plastic sheet by sputtering or ion plating to maintain forward visibility. It is a transparent sheet that shields radiant heat across the entire width of the body, making it possible to shield radiant heat.

This invention will be explained in detail below. Examples of materials for the transparent plastic sheet used in this invention include polycarbonate, acrylic resin, and polyester. In addition, as the metal forming the metal vapor deposition film, Ni
, Cr, or alloys containing them, such as Ni-Cr alloys, SuS3O4, SuS3lOS, and the like.

As shown in Figure 3, on the plastic sheet 5 soil,
A metal vapor deposition film 6 is formed to a thickness of Vl2O to 120λ by sputtering or ion plating.

As shown in the attached table (1st to 3rd examples, 5th example), when the film thickness is 20λ or less, the radiant heat transmittance is almost the same as that of conventional products, and when it is 120X or more, it becomes visible. The transmittance of the vehicle also decreases, making it impossible to ensure forward visibility. The radiant heat shielding transparent sheet 7 thus formed can be used alone, as shown in FIG. 3, on a holding frame 8 formed close to the rear window, or as shown in FIG. It is used by being attached to a rear window glass 10 via an adhesive layer 9.

In such a case, as shown by the solid line in FIG. 1, the radiation heat shielding transparent sheet 7 can suppress the transmission of visible rays and heat rays at approximately the same rate among the rays associated with solar radiation. Temperature rise can be suppressed, the visible range transmittance is 2570 or more, and forward visibility is maintained. In the above, the transparent plastic sheet 5 is
Sputtering angle 5-60 for sputtering target
The film thickness may be changed steplessly from one end of the transparent plastic sheet 5 to the other end by sputtering the transparent plastic sheet 5 while fixing the transparent plastic sheet 5 so that the transparent plastic sheet 5 is fixed at the same time.

Then, when attached to the rear window 10 as shown in FIG. 5, the light transmittance at the boundary with the glass hardly changes, so the driver's eyes do not get tired when checking the rear, and It gradually transitions from dark color to light color, and is excellent in design, especially in terms of color and gradation. Furthermore, it is also possible to change the film thickness in stages by masking or the like, which can accentuate the change in color tone and enhance the design effect. Since this invention has the above-mentioned configuration, it is possible to suppress the transmission of heat rays as well as visible rays among the light rays accompanying sunlight, and it is possible to suppress the transmission of radiant heat while maintaining a certain degree of forward visibility. This is effective in preventing the temperature inside the car from rising during the summer.

Examples of this invention will be described below.

Fourth Example Sputtering was performed on the same material and the same metal as in the first example under the following conditions.

Fifth Example Ni was sputtered onto a polyester sheet (t=12μ) under the same conditions as in the first example to give a film thickness of 2.0λ.

After the sputtering treatment, a water-soluble polymer adhesive was applied to the metal surface using a roll coater. This polyester sheet was adhered to a glass plate (3t), and the visible region transmittance and radial heat transmittance were measured. The visible range transmittance and radiant heat transmittance of the first to third examples and the fifth example are shown in the attached table.

It can be seen that the radiant heat transmittance is improved compared to the conventional example. Further, the solid lines in FIG. 1 indicate the light transmission curves in each wavelength range of the second embodiment. Regarding Examples 2 and 4 above, physical property tests on the metal vapor deposited films were conducted for adhesion, heat resistance test, hot water resistance test, humidity resistance test, cold/hot/humid cycle test, light resistance test, and chemical resistance test. However, all the results were good, and it was found that the radiant heat shielding sheet of the present invention can withstand use even under fairly severe conditions. }, each test method is as follows.

(1) Adhesion: Taping test (2) Heat resistance test: After being left at 80°C for 240 hours, the appearance and adhesion were observed.

(3) Hot water resistance test: After immersing in water at 40°C for 24Oh, look at the appearance and adhesion.

(4) Humidity test: 50℃, RH95ZO or higher x24
After leaving it for a while, check the appearance and adhesion.

Check appearance and adhesion.

(6) Light resistance test: After 400 hours of testing, look at the appearance and adhesion performance using a fade meter.

(7) Chemical resistance test: 1 mt of each of the following chemicals was dropped onto the metal vapor deposited film, and the appearance was observed after leaving it for 24 hours.

1 gasoline, 2 engine oil, 3 window wash, 4 protective wax, 5 wax remover () length oil,
7Ha0H (0.1N), 8H,S04 (0.1
N), 9 ethyl alcohol, O hair conditioner, 5 antifreeze, @brake fluid.

The light transmittance in the visible range of the fourth example is A-) in Figure 5.
As it moves toward B, it shows changes as shown in FIG.

In addition, Figure 7 shows the film thickness of various metal vapor deposited films and the infrared region (15
This is a graph showing the relationship between heat ray transmittance and film thickness for a film thickness of 00 nm).From this graph, At has almost no heat ray shielding effect even with a film thickness of about 150X, and transition metals such as Ni and Cr or their It can be seen that the contained SuS, Ni-Cr alloys, etc. have the effect of shielding heat rays of 20 to 30X and 30 to 4070.

In particular, in the case of Cr, the heat ray shielding effect is remarkable.

[Brief explanation of the drawing]

Fig. 1 is a graph showing the light transmittance curves of conventional examples 1 and 2 and the second embodiment, Fig. 2 is a schematic diagram showing a method for measuring radiant heat transmittance, and Fig. 3 is a radiant heat shield of the present invention. FIG. 4 is a cross-sectional view showing the sheet, FIG.
The figure is a front view of a rear window equipped with a radiation heat shielding sheet in which the thickness of the metal vapor-deposited film is changed steplessly. FIG. 7 is a graph showing the relationship between the film thickness and heat ray transmittance of various metal vapor deposited films. 5... (transparent) plastic sheet, 6... metal vapor deposited film, 7... radiant heat shielding sheet.

Claims (1)

[Claims] 1. A radiant heat shielding transparent sheet having a structure in which a 20 to 120 Å metal vapor deposition film of transition metals such as chromium and nickel or alloys containing these is formed on the surface of a transparent plastic sheet by sputtering or ion plating. . 2. The radiant heat shielding transparent sheet according to claim 1, wherein the metal vapor deposition film is formed on the surface of the transparent plastic sheet by changing the film thickness stepwise or steplessly.