JPH064309B2 - Heat ray reflective transparent plate and method for manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention is a colored heat ray reflective transparent plate, and in particular, it has a relatively high visible light transmittance, exhibits a beautiful appearance color, and effectively shields solar radiant energy. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat ray reflective transparent plate for buildings or automobiles and a manufacturing method thereof.

[Prior Art] Conventionally, as a heat ray reflective transparent plate of this kind, Japanese Patent Publication No. 47-1.
It is known that at least one coating of carbide or nitride is attached to a glass plate as described in US Pat. No. 4,820,480. The formation of at least one of these carbides or nitrides on the surface of the glass plate is usually carried out by a high frequency sputtering method using a carbide or a nitride as a target, and particularly when a large target is used, the target is used. However, it was difficult to carry out by the DC sputtering method because of its low electrical conductivity.

[Problems to be Solved by the Invention] However, heat-reflecting glass in which at least one coating of carbide or nitride is attached to a glass plate has mechanical strength and chemical durability. Since there are few numbers, there is a defect that the heat ray reflection performance is inferior, and to form a coating on a large glass plate with a large target, a high frequency sputtering method must be used, and a large capacity high frequency power source is required. Also, there is a drawback that the formation of a coating film is remarkably reduced by the so-called reverse sputtering phenomenon from the glass plate side, and it is difficult to form a stable coating film.

[Means for Solving the Problems] The present invention is a heat ray reflective transparent plate in which a transparent plate is coated with a silicon carbide coating film containing 1.0% by weight to 10% by weight of free silicon. Is coated by direct current sputtering of a carbon silicon target containing 10% by weight to 20% by weight of free silicon atoms in a reduced pressure atmosphere, and has a thickness of 400 to 1500 Å. It is a plate. A second aspect of the present invention is a method for producing a heat ray reflector in which a silicon-containing silicon carbide coating film is coated on a transparent plate, and decompressing a silicon carbide target containing 10 wt% to 20 wt% of free silicon. A method for producing a heat ray reflective transparent plate, characterized in that direct current sputtering is performed in an atmosphere, and silicon molecules and silicon carbide molecules sputtered from the target are deposited on the transparent plate.

In the present invention, a glass plate having a refractive index of 1.3 to 1.8 or a synthetic resin plate is used as the transparent plate. The heat ray reflective transparent plate according to the present invention can be achieved by forming a silicon carbide film on the transparent plate by direct-current sputtering using a silicon carbide plate containing free silicon atoms as a target.

Here, as the target, a silicon carbide plate containing 10% by weight to 20% by weight of free silicon atoms is used. By using 10 wt% to 20 wt% of free silicon atoms for the target, the formed silicon carbide film contains approximately 1.0 wt% to 10 wt% of free silicon atoms.

[Operation] According to the present invention, the number of silicon atoms released in the silicon carbide film is 1.0
Since the content is from 10% by weight to 10% by weight, the number of free electrons can be increased, the heat ray reflection function can be enhanced, and the mechanical strength and chemical durability of the coating can be maintained. When the amount of free silicon atoms in the coating is 1.0% by weight or less, the heat ray reflecting function is not improved so much, and when it is 10% by weight or more, the durability of the coating becomes poor.

Further, since a silicon carbide plate containing free silicon atoms can be used as a target for forming a film, the electric resistivity of the target can be made lower than 1 Ω · cm, so that a stable film can be formed by the DC sputtering method. .

[Examples] As the silicon carbide target, a silicon carbide target synthesized by a so-called silicon injection method was used, in which a compact made of silicon carbide and carbon was used as a raw material and silicon was injected while heating at about 1650 ° C. According to the chemical analysis, free silicon was 18% and electric resistivity was 0.5 Ω · cm.

Put the cleaned 2mm thick plate glass substrate in the vacuum chamber,
After evacuating to 5 × 10 _-3 Pa with a cryopump, A
The r gas was introduced and the pressure was adjusted to 0.3 Pa. The above-mentioned silicon carbide target was set on the cathode at a position facing the glass substrate. Electric power was supplied from a DC power source connected to the cathode to cause sputtering. The current value was set to 2 A and maintained for about 5 minutes. After that, the current value was set to 0.65 A, the shutter between the target and the glass substrate was opened, and the thin film was attached to the glass substrate. After 2 minutes, the shutter was closed and film formation was completed. The potential of the cathode during film formation was -406V.

When this sample (1) was taken out into the atmosphere and the thickness of the thin film was measured with a surface roughness meter, it was 570A. When the visible light transmittance and the visible light reflectance on the glass surface side of this sample (1) were measured, they were 31.7% and 38.6%, respectively. ^L by hue provisions of CIE1976 from the glass surface side ^*, a *, the ^{b *} color space ^L * = 6
^8.3, a * = ^-0.7, is b ^× = 29.3 had the shape of a beautiful gold color. 380 nm of this sample (1)
The spectral reflectance in the wavelength range from 1 to 1800 nm is shown by the curve (10) in FIG. This film contains 1N hydrochloric acid and 1N
Even after being left to stand for 6 hours in a specified caustic soda solution, there was substantially no change in the optical characteristics. The amount of free silicon contained in the film was determined by X-ray photoelectron spectroscopy analysis to be about 5% by weight.
Met.

As a comparative example, the curve (11) in FIG. 1 shows the spectral reflectance of the heat-reflecting glass in which a conventional silicon carbide film having the same thickness as that of the example and having no free silicon atoms was formed by high frequency sputtering. It was

Next, using the same silicon carbide target as described above, samples 2 to 4 of silicon carbide film-adhered glass having different film thicknesses were prepared by changing the applied current or the sputtering time in the same procedure as described above. The optical characteristics of Samples 1 to 4 are shown in Table 1, and the manner in which the hue changes due to the change in film thickness is shown in the CIE L ^* , a ^* , and b ^* color spaces in FIG.

[Effects of the Invention] As described above, according to the present invention, the number of free electrons in the silicon carbide film of the heat ray reflective transparent body can be increased to enhance the heat ray reflection function, and the thickness of the silicon carbide film can be changed. By
Due to the interference of the reflected light on both surfaces of the layer, it is possible to obtain a heat ray reflective transparent body having a reflection color of various hues.

Moreover, in order to realize it, direct current sputtering is carried out using a conductive silicon carbide plate containing free silicon atoms as a target, and a heat ray reflection glass plate having a large area for construction and automobiles is obtained. Can also be realized.

[Brief description of drawings]

The drawings show examples of the present invention and comparative examples. FIG. 1 shows the spectral reflectance characteristics of sample (1) and the comparative example, and FIG. 2 shows samples (1) to (() of the present invention. It is a figure which shows the reflection color change of 4). 10: Spectral reflectance characteristic curve of the sample of the present invention 11: Spectral reflectance characteristic curve of Comparative Example

Claims (2)

[Claims] 1. A heat ray reflective transparent plate comprising a transparent plate coated with a silicon carbide coating containing 1.0% by weight to 10% by weight of free silicon, said coating being 10% by weight to 20% by weight. %
Is coated by direct current sputtering of a silicon carbide target containing free silicon atoms in a reduced pressure atmosphere,
A heat ray reflective transparent plate having a thickness of 400 to 1500 Å. 2. A method for producing a heat ray reflector in which a silicon-containing silicon carbide coating film is coated on a transparent plate.
A heat wire characterized by subjecting a target of silicon carbide containing 20% by weight to 20% by weight of free silicon to direct current sputtering in a reduced pressure atmosphere to deposit silicon molecules and silicon carbide molecules sputtered from the target on a transparent plate. Manufacturing method of reflective transparent plate.