JPH03257042A - Glass having low transmissivity - Google Patents

Abstract

PURPOSE:To form a layer absorbing part of sunbeams in a glass sheet and to reduce the light transmissivity of the sheet by implanting ions of a specified element into the sheet. CONSTITUTION:Ions of at least one kind of element selected from among Si, Al, Ti, Cr, Co, Ni and Zr are implanted into a glass sheet 1 with an ion implanting device to form a light absorbing layer 2 near the surface of the sheet 1. This layer 2 has the highest atomic density of the element at 3-30nm depth from the surface of the sheet 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to glass that transmits a portion of visible light and absorbs a portion of visible light, and is particularly suitable for use as window glass for buildings and automobiles. Regarding glass suitable for use.

[Conventional technology]

Glass with low transmittance has been used in buildings and automobiles from the viewpoint of energy conservation and privacy protection. These are broadly classified into cases in which a component that absorbs visible light is contained in the glass (heat ray absorbing glass) and cases in which a reflective film that reduces transmittance is formed on the glass surface (heat ray reflective glass). In recent years, low-transmittance heat-reflecting glass, which is coated with a film on the glass surface using a sputtering method, has been widely used because of its low re-radiation, high energy-saving effect, and beautiful appearance. Glass with low sunlight transmittance is made by coating the glass surface with a metal nitride film combined with a transparent oxide film, as disclosed in Japanese Patent Application Laid-Open No. 60-36355. Cr, as disclosed in Japanese Patent Application Laid-Open No. 62-158139,
It is known that a glass surface is coated with a combination of a metal film such as Ni or Ti and a transparent oxide film.

[Problem to be solved by the invention]

However, when the surface of the glass plate is coated with a metal nitride film or a metal film, the adhesion between the film and the glass is not necessarily sufficient, and the drawback is that it is easily damaged by external scratches. there were. Also sulfur,
There have been serious problems in that the presence of trace amounts of corrosive gases such as chlorine or oxidizing gases such as oxygen causes the film to change or deteriorate, resulting in changes in optical properties.

[Means to solve the problem]

The present invention has been made to solve the above-mentioned problems. Ti.

A glass plate in which a light absorption layer is formed near the inner surface of the glass plate by implanting at least one element selected from the group of elements consisting of Cr, Co, Ni, and Zr into the glass plate using an ion implantation method. be.

All of the above-mentioned elements in the first group are implanted near the inner surface of the glass plate by ion implantation to reduce the visible light transmittance of the glass plate and at the same time make the color tone of the glass due to reflected and transmitted light glare. Rather than a dark golden tone, the color can be a calm neutral color or a color close to a neutral color. Further, in order to subtly change the color tone of the reflected color or the transmitted color, an alloy consisting of two or more of the above-mentioned elements can be used. Moreover, some of the above-mentioned elements are selected from relatively small atomic numbers, and these elements or alloys can be easily ionized and ion-implanted into the glass plate.

The light absorption layer formed inside the glass plate can be formed by a known ion implantation method in which metal is ionized in a reduced pressure atmosphere, the metal ions are accelerated, and then implanted into the inside of the glass. It is desirable that the density of the metal to be ion-implanted is approximately the same as the atomic density of the glass, and the density distribution of the metal to be ion-implanted in the depth direction inside the substrate depends on the dose of metal ions during ion implantation and the atomic density of the glass. Controlled by adjusting acceleration. The concentration distribution of the ion-implanted metal in the depth direction usually has a Gaussian distribution or a distribution approximating a Gaussian distribution. The depth from the glass surface where the metal layer to be ion-implanted has the highest density is adjusted to 3 to 30 nm, and especially when used as a window glass, optical factors such as visible light reflectance and visible light transmittance are From the characteristics 5~
It is preferable to adjust by 15nd. Further, the thickness of the light absorption layer made of a metal in which the ion-implanted atomic density is approximately represented by a Gaussian distribution is preferably 3 to 20 nm, more preferably 5 to 20 nm, expressed by the standard deviation of the Gaussian distribution.
ng is particularly preferred from the viewpoint of optical properties.

The density distribution in the depth direction of the metal layer described above is adjusted by the ion dose during ion implantation, the ion implantation acceleration voltage, and the heat treatment conditions after ion implantation. In addition, the density distribution of metal formed in the depth direction inside the glass becomes a tail-like distribution, but if the distribution exists substantially inside the glass, the tail will reach the surface of the glass. It doesn't matter.

The glass plate used in the present invention is not particularly limited in glass composition, and may include silicate glasses such as quartz glass, high silica glass, soda lime silica glass, aluminosilicate glass, and borosilicate glass, Salt glass can be used.

[Effect]

The light absorbing layer made of metal that reduces the transmittance of sunlight according to the present invention is formed near the inner surface of the glass and is not exposed on the surface of the glass, so it is not exposed to scratches or abrasion from the outside. Also, it will not change or deteriorate due to contact with corrosive gases. Furthermore, by adjusting the type of metal in the light-absorbing metal layer and the density distribution of the metal, it is possible to create glass that reduces sunlight transmittance at various ratios.

〔Example〕

FIG. 1 (al is a partial cross-sectional view of the glass according to the present invention,
A light absorbing layer 2 made of metal implanted by ion implantation is formed near the inner surface of the glass plate 1 . 1) is a diagram schematically representing the density distribution of the implanted metal in the depth direction inside the glass, FIGS. 2 and 3 are diagrams showing the optical characteristics of the embodiment of the present invention, and FIG. The figure is a partial cross-sectional view of a conventional glass in which the glass surface is coated with a metal layer, and a transparent layer 4 is coated on the metal coating layer 3.

Example 1 A 5-fi thick quartz glass was used as the glass plate.

Using an ion implanter, Cr ions were implanted at an acceleration voltage of 9 keV at a dose of 1X10''/-.

Thereafter, heat treatment was performed at a temperature of about 550° C. for 1 hour.

This formed a layer of Cr atoms having a maximum density at a depth of about Ionm and an implantation thickness of about 5 nm. (The density distribution of Cr was observed using a secondary ion mass spectrometer.)
When the transmittance and reflectance of the obtained Sample 1 in the visible light and near infrared regions were measured, a low transmittance glass with a neutral color tone was obtained as shown in FIG. In Figure 2, T indicates transmittance, R indicates reflectance, and Ra and R□ are the reflectances when light is incident from the ion-implanted glass surface and the surface opposite to the ion-implanted glass surface, respectively. . The durability of Sample 1 was evaluated. Wear resistance was determined by measuring the haze value in accordance with JIS R3212 after applying 300 rotational abrasions with a load of 500g using a taper abrasion tester. Indicated.

For chemical resistance, changes in transmittance were measured after immersion in 1N sulfuric acid and 1N caustic soda for 6 hours, and there was virtually no change.

Example 2 A quartz glass with a thickness of 5 mm was used as the glass plate.

Using an ion implanter, Ti ions were implanted at an acceleration voltage of 8 keV at a dose of 1X10''/clI.

Thereafter, heat treatment was performed at a temperature of about 550° C. for 1 hour.

This results in a maximum density at a depth of about 10n+*,
A layer of Ti atoms with an implantation thickness of approximately 5nlll was formed. (
The density distribution of Ti was observed using a secondary ion mass spectrometer. ) The transmittance and reflectance of the obtained sample 2 in the visible light and near infrared regions were measured, and as shown in FIG. 3, a low transmittance glass with a neutral color tone was obtained. In FIG. 3, T indicates transmittance, R indicates reflectance, and R^+R1 indicates reflectance when light is incident from the ion-implanted glass surface and the surface opposite to the ion-implanted glass surface, respectively. When the durability of Sample 2 was evaluated in the same manner as in Example 1, the haze rate in the taper abrasion test was approximately 1.5%, and there was virtually no change in transmittance in terms of chemical resistance.

Example 3 Same as Example 1 except that the type of metal and the accelerating voltage of the metal ions during implantation were changed.
Al near the inner surface of the glass.

Samples 3 to 7 were prepared in which absorbing layers each made of a single metal such as St, Ni, Co, or Zr were formed. The optical properties of these samples are shown together with Samples 1 and 2 in Table 1. Further, when samples 3 to 7 were also subjected to the same abrasion resistance test as in Example 1, the haze rate was about 1.5% in all of them.

Further, when the same chemical resistance test as in Example 1 was conducted, there was almost no change in transmittance and no change in appearance was observed.

Comparative example A 5-fi thick quartz glass was used as the glass plate.

On the surface of this glass is a 8.5 nm Ni layer and a 28 nm S layer.
Comparative samples were obtained by successively sputtering coatings of nO□ layers. The Ni layer was coated by direct current sputtering in an atmosphere of 0.04 Pa pressure consisting of 100% argon using a Ni target, and the SnO□ layer was coated using argon 60% oxygen 4 using a Sn target.
This was carried out by direct current sputtering in an atmosphere of a pressure of 0.04 Pa consisting of a mixed gas with a composition of 0%. The visible light transmittance of the obtained comparison sample was 46%.

When a wear resistance test was conducted in the same manner as in the example, 30
Many scratches were observed on the surface of the coating layer due to rotation. Further, when the same chemical resistance test as in Example 1 was conducted, the coating layer was found to have significantly deteriorated in quality as seen with the naked eye.

From the above, it can be seen that the glass according to the present invention has significantly improved mechanical strength and chemical stability.

〔Effect of the invention〕

In the glass of the present invention, the metal layer that absorbs a portion of sunlight and reduces light transmittance is formed inside the glass plate and is not exposed on the surface, so it is not exposed to mechanical external forces such as scratches or abrasion. It is not subject to chemical attack from the outside atmosphere. Therefore, when used as window glass, it can be used as a single sheet without having to use laminated or double-glazed glass.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional view for explaining the present invention in detail;
FIGS. 2 and 3 are diagrams showing optical characteristics of embodiments of the present invention,
FIG. 4 is a partial cross-sectional view of a conventional glass. DESCRIPTION OF SYMBOLS 1...Glass plate, 2...Light absorption layer made of ion-implanted metal, 3...Metal coating layer, 4...Coated transparent layer

Claims (1)

[Claims] 1) By implanting at least one element selected from the group consisting of Si, Al, Ti, Cr, Co, Ni, and Zr into the glass plate by ion implantation, the inside of the glass plate is A glass plate with a light absorption layer formed near its surface. 2) The glass plate according to claim 1, wherein a portion of the element forming the light absorption layer having the highest atomic density is 3 to 30 nm from the surface of the glass plate.