JP2505686B2 - Red light transmissive white opal glass and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a red light transmitting white opal glass mainly used in the fields of ornaments, craft glass, furniture building materials and the like and a method for producing the same.

[0002]

2. Description of the Related Art Opal glass similar to the red light transmitting white opal glass obtained by the present invention uses various fluorides, chlorides, phosphates and oxides such as tin, zirconium, titanium and antimony as emulsifiers. In addition to the above, it is manufactured by a phase-separating heat treatment of a phase-separating glass such as sodium borosilicate glass.

These opal glasses are produced by forming emulsions or fine grain boundaries in the base glass. Although these opal glasses are translucent, they are characterized in that the light transmitted through the emulsion or grain boundaries formed in the basic glass is generally dark red.

[0004] For the purpose of developing an effective utilization method of volcanic ash soil shirasu, the present applicant manufactured opal glass based on heat treatment phase separation from basic glass using shirasu as a raw material and processed it into ornaments and the like. He has continued to earnestly research such as producing local special products, and has already applied for a patent for the related technology (Japanese Patent Application Laid-Open No. 141639, “Method for manufacturing Shirasu opal glass”, Japanese Patent Laid-Open No. 62-2)
No. 97240, "Transmitted light-reflected scattered light, Hue difference opal glass and method for producing the same", JP-A No. 2830/1988.
(See Japanese Patent Laid-Open Publication No. 1994-242, "Method for producing red opal glass."

These basic glass raw materials are silicic acid-alumina-boron oxide-calcium carbonate-magnesium oxide-alkali metal oxides, or silicic acid-alumina-boron oxide-phosphoric acid-calcium carbonate-magnesium oxide-alkali metal. Consisting of oxides, natural resources of volcanic ash soil shirasu and feldspar are used as a source of silicic acid and alumina for glass formation. Similar to sodium borosilicate glass, various opal for decoration by phase separation heat treatment of base glass It shows that glasses can be produced.

[0006]

The present invention is particularly related to the "method for producing a reddish opal glass" disclosed in Japanese Unexamined Patent Publication No. 2830/1988, and the method for producing this reddish opal glass is described. After that, the applicant continued to research further, and by using a different basic glass raw material, vitrification auxiliary additive, and colorant composition, a special "red light-transmissive white opal glass" was obtained. It is based on what we were able to do.

An object of the present invention is to provide a red translucent white opal glass which is a white translucent emulsion glass and has a characteristic of transmitting bright reddish orange light, and a method for producing the same.

[0008]

[Means and Actions for Solving the Problems] A method for producing a red opal glass according to the present invention is a method for producing a red opal glass by subjecting a basic glass which has been colored red due to a gold colloid to a phase separation heat treatment. To be formed. On the other hand, in the present invention, the amount of gold, which is a colorant that imparts a red color to the glass, is reduced to about half of the amount of gold added when the basic glass exhibits a red color. By controlling the color development, the opal glass after the phase-separation heat treatment is manufactured by adjusting so as to give a white coloration. It is a special example of red-based opal glass because it is white, but transmits reddish-orange light well and reflects it to project red light on the surface.

To explain the coloring principle, ordinary white glass is white when light of all wavelengths in the visible light spectrum of sunlight is scattered by fine particles or grain boundaries of non-uniform size generated in the glass. Becomes Therefore, in general white opal glass, the incident light is a light of all wavelengths that is scattered by the fine particles or grain boundaries in the glass, and the amount of light that is scattered is reduced while the amount of light is reduced while passing through the glass. (Red light with long wavelength)
Is slightly transmitted, resulting in dark red transmitted light.

The state of light transmission and scattering of these general white opal glasses will be schematically described with reference to FIG.
As shown in, the light B11 incident from the surface of the white opal glass 10 is scattered by the fine particles in the glass,
The amount of light decreases in the transmission process, and dark red light is slightly transmitted. The scattered light is shown by a broken line B12 and the transmitted light is shown by a chain line B13.
As described above, since the amount of light is reduced in the transmission process, almost no light that is transmitted through the white opal glass 10 and then reflected by the reflection plate 20 to appear on the surface of the white opal glass 10 is observed.

On the other hand, in the red light transmissive white opal glass according to the present invention, reddish light transmits better than the normal opal glass described above, and when a reflecting plate is placed on the back surface of the white opal glass having a thickness of 5 mm, the red opal glass is red. The orange light is transmitted and then reflected,
It even appears on the surface. That is, in the visible light spectrum, the transmittance of reddish light having a long wavelength is larger than that of general opal glass.

An example of the light transmission spectrum of the red light-transmissive white opal glass produced by the present invention is shown in FIG. Figure 2 shows the visible light transmission characteristics of red light transmissive white opal glass with distilled water as a control, where the vertical axis represents the light transmittance.
The horizontal axis represents the wavelength of light. From this light transmission spectrum, in the red light transmissive white opal glass according to the present invention, light having a short wavelength of 600 nm or less is hardly transmitted due to scattering, and red light from 600 nm to 800 nm is well transmitted, In particular, it is understood that about 50% of the intensity of the incident light is transmitted through the light in the vicinity of 700 nm to 800 nm.
Based on this light transmission property, a red light transmissive white opal glass which is a white emulsion glass but transmits red light well can be obtained. FIG. 1 schematically shows how the light is transmitted and scattered.

That is, of the light B1 incident from the surface of the red light transmissive white opal glass 1, light having a short wavelength of 600 nm or less is scattered by the fine particles in the glass. The scattered light is shown by the broken line B2. On the other hand, the reddish light from 600 nm to 800 nm is well transmitted through the red light transmissive white opal glass 1 as shown by the chain line B3, is reflected by the reflection plate 2 and appears on the surface of the white opal glass 1.

Briefly describing the manufacturing principle, the method for manufacturing a red light transmitting white opal glass according to the present invention is as follows.
The basic manufacturing principle is to generate fine grain boundaries by phase separation by heat treatment of the basic glass. That is, a basic glass raw material set in a specific range, a vitrification auxiliary additive,
By using a colorant composed of gold as a main material and a complex of rare earth oxides, a molten base glass is heat-treated at a temperature of 700 to 800 ° C. to cause phase separation, and a white emulsion opal glass is obtained. Manufactured. In order for the white emulsion opal glass produced by such a method to show the transmission and scattering of light as shown in FIGS. 1 and 2, the particle system distribution of the fine grain boundaries that scatter light is relatively uniform. In addition, it is considered necessary as a condition for generation that the density of the fine particles forming the grain boundaries is controlled to an appropriate density that does not prevent the transmission of red light having a long wavelength. Further, when gold is not used as the colorant, it is difficult to produce the red light-transmissive white opal glass of the present invention, and thus the red light of the transmitted light is also related to the red-orange coloration due to the gold colloid. It is thought that

Next, the basic glass raw material, the vitrification auxiliary agent, and the colorant for producing the red light transmitting white opal glass of the present invention will be described. The composition of the basic glass raw material is silicic acid-alumina-oxidation. Boron-calcium carbonate-
Magnesium oxide-Alkali metal oxides, 0-50% by weight of volcanic ash soil shirasu in glass raw material, 20
~ 70% feldspar, 5-15% silicic acid, 0-10% alumina, 15-20% boron oxide, 10-18% calcium carbonate, 0-5% magnesium oxide, 1-10
% Alkali metal oxide carbonates (single or complex of sodium carbonate, potassium carbonate, lithium carbonate, etc.) are used.

Among the above-mentioned raw materials, shirasu and feldspar are used as a source of silicic acid and alumina, but have a characteristic that they have better meltability and can carry out a low-cost melting operation than those using pure silicic acid and alumina. . Silicic acid is used as a supplement to supplement silicic acid when a large amount of feldspar with a low silicic acid content is used, and alumina has the effect of suppressing the phase separation of the basic glass. Is added in. Boron acid acts as a phase separating agent for the basic glass, and calcium oxide and magnesium oxide have an effect of promoting phase separation. Magnesium oxide has an effect of reducing cracks due to abnormal expansion of the base glass, in addition to the effect of promoting phase separation. Alkali metal oxides are also contained in shirasu and feldspar, and have the function of lowering the viscosity of glass and improving the meltability, but when the addition amount increases, cracking due to abnormal expansion occurs.

The vitrification auxiliary additive is 0 to 0% by weight.
5% barium carbonate, 0-3% fluoride salt (single or complex of calcium fluoride, sodium borofluoride, etc.) is used. These vitrification auxiliary additives have the effects of lowering the viscosity of the basic glass melt and improving the breakage of bubbles. As the colorant, the weight percentage of the basic glass raw material and the vitrification auxiliary additive is 0.002 to 0.
0 to 3% of rare earth element oxides (cerium oxide, yttrium oxide, neodymium oxide, etc., alone or in combination) are used with 015% gold as the main component. Gold gives a reddish orange color to the basic glass, and rare earth element oxides have a function of subtly changing the hue of white.

Next, the manufacturing method will be described. A raw material mixture prepared by the above raw material composition is melted at 1200 to 1500 ° C. and then rapidly cooled to obtain a basic glass. Then 700-
A red light-transmissive white opal glass is manufactured by heating at 800 ° C. for 5 to 20 minutes to cause phase separation to obtain an emulsion glass.

[0019]

EXAMPLE Next, one example of producing the red light transmitting opal glass of the present invention will be described. The composition and weight (grams) of the basic glass material were set to Table 1, the composition and weight (grams) of additives and colorants were set to the composition and weight shown in Table 2, and these raw materials were mixed. Then, this glass raw material mixture was melted at a temperature of 1200 to 1500 ° C. and then rapidly cooled to obtain a base glass. Next, this basic glass is
A red light-transmitting white opal glass was obtained by heating at a temperature of 800 ° C. for 5 to 20 minutes to cause phase separation to obtain an emulsion glass. The light transmission spectrum of the red light transmissive white opal glass thus obtained is shown in FIG.

The compositions of shirasu and feldspar in Table 1 are as follows:
It is published in the paper by Tadaharu Kuroiwa on page 625, Vol. 91 (1975) of the Japan Mining Association, and shown in Table 3.

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

[Table 3]

[0024]

According to the present invention, a red translucent white opal glass which is a white translucent emulsion glass and has a characteristic of transmitting bright reddish orange light can be obtained. Therefore, when the red light-transmissive white opal glass obtained by the present invention is processed into a decorative product, it has the property of emitting red light on the surface of the white emulsion glass. It can be used as a raw material and can accelerate the development of new products in those fields.
In addition, since it is manufactured by using natural resources such as volcanic ash soil shirasu and feldspar, it can be used as a local specialty product that produces the natural resources, and local companies can be activated.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing how light is scattered and transmitted in a red light transmissive white opal glass manufactured by the present invention.

FIG. 2 is a graph showing a light transmission spectrum of a red light transmitting white opal glass manufactured according to the present invention.

FIG. 3 is a schematic diagram showing how light is scattered and transmitted in a conventional white opal glass.

[Explanation of symbols]

 1 Red light transmissive white opal glass

Claims (2)

(57) [Claims] 1. A raw material is a mixture of a basic glass raw material, a vitrification auxiliary additive, and a coloring agent containing gold as a main component, and the basic glass raw material is 0 to 50% by weight of volcanic ash soil "Shirasu", 20-70% feldspar, 5-15% silicic acid, 0-10% alumina, 15-20% boron oxide, 10-18% calcium carbonate, 0-5
% Magnesium oxide, 0-10% alkali metal oxides, and the vitrification aid additive contains 0-5% barium carbonate by weight and 0-3% fluorides. The coloring agent is contained in an amount of 0.002 to 0.% by weight with respect to the weight of the basic glass raw material and the vitrification auxiliary additive.
015% of gold and 0 to 3% of rare earth oxides, the raw material mixture is melted at a temperature of 1200 to 1500 ° C. and then cooled to obtain a basic glass, and the basic glass is 700 to 8
A method for producing a red light-transmissive white opal glass which is heated to 00 ° C. to cause phase separation. 2. A red light-transmissive white opal glass produced by the production method according to claim 1.