JPH0573701B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a transmitted light-reflected scattered light hue difference opal glass in which there is a significant difference between transmitted light and scattered light, and a method for producing the same, and is mainly used in decorative glass and industrial arts. The present invention relates to a transmitted light-reflected scattered light hue contrast opal glass used in the fields of glass, glass for building materials, etc., and a method for manufacturing the same. The method for manufacturing transmitted light-reflected scattered light hue contrast opal glass according to the present invention makes it possible to use volcanic ash soil shirasu, which is an unused resource, as decorative glass, craft glass, and glass for building materials, as well as chemical durability. In order to make it possible to use glass for tableware and special bottles,
It can be widely used in the glass industry. [Prior art] General opal glass is manufactured using various fluorides, chlorides, phosphates, tin, zirconium, titanium, and antimony oxide as opacifying agents, as well as phase-splitting glasses such as soda borosilicate glass. It can also be produced by heat treatment. The applicant produced phase-splitting glass using volcanic ash soil shirasu as one of the raw materials, and produced phase splitting through heat treatment to produce shirasu opal glass that can be used for decoration (patent application published 19861
(See Publication No. 141639). [Problems to be Solved by the Invention] Opal glass using an opacifying agent generally becomes milky-white opal glass (opal white glass), and opal glass using phase splitting glass becomes blue-white translucent opal glass. These opal glasses can be given a unique color by using various colorants. However, although these opal glasses produce beautiful scattered light (the apparent color of the glass), they have the disadvantage that the light that slightly passes through them has a dark brown color. This invention is based on reflected scattered light, that is, the apparent color of the glass is a dark color in the brown family, but the transmitted light has a bright hue such as green, blue, red-blue-green mosaic, etc. The purpose is to provide glass and its manufacturing method. [Means and effects for solving the problem] In the present invention, volcanic ash soil shirasu, feldspar,
Silicic acid-alumina-boron oxide-phosphoric acid-alkaline earth oxide-alkali using alumina, boron oxide, phosphoric acid, alkaline earth metal oxide, alkali metal oxide, or various general glass raw materials Metal oxides are used as the basic opal glass raw material, and gold, cerium oxide, manganese dioxide, and other metal element coloring agents or decolorizing agents are added as colorants to this basic opal glass raw material in combination, and as necessary After mixing, 1200~1500℃
The base glass is obtained by heating and melting the glass and then cooling it. This basic glass is maintained between 600 and 1000°C to induce phase separation of the glass, thereby obtaining a transmitted light-reflected scattered light hue difference opal glass in an opal state (semi-transparent state). The transmitted light-reflected scattered light hue difference opal glass is characterized in that the reflected scattered light (apparent color of the glass) is brownish, and the transmitted light is green-blue, red-blue-green mosaic color, or red. has. Such a transmitted light-reflected scattered light hue contrast opal glass has never been manufactured, and in particular, there is no example of an opal glass similar to the present invention manufactured using volcanic ash soil shirasu as a raw material. In general, when phase splitting glass containing a suitable amount of boron oxide or phosphoric acid is reheated to a temperature above its glass transition point, the glass components move, that is, phase separation of the glass occurs, and the glass changes from a transparent glass to an opal state (translucent). state) of glass. Taking advantage of this phenomenon, the present inventors have developed shirasu opal glass, which is used for decoration, from glass with a five-raw material composition of shirasu - feldspar - boron oxide - calcium oxide - sodium oxide, which uses volcanic ash soil shirasu as one of the raw materials. Already developed (patent application published in 1988)
(Refer to Publication No. 141639). The present inventor further conducted research in order to improve the moldability and acid resistance of the Shirasu Opal Glass, as well as to solve the problem of color fading when melting in large quantities.
By using boron oxide and phosphoric acid together as glass phase splitting agents, we have made it possible to create a glass composition with increased alumina content, which has the effect of improving glass moldability. Although this glass composition improved the durability of Shirasu opal glass and the discoloration during large-scale melting, the coloration during phase separation also changed significantly. In other words, when colored with a combination of gold-cerium oxide-manganese dioxide or gold-rare earth oxide-metal oxide colorant and decolorizer, the hue of transmitted light and reflected and scattered light are significantly different from each other. (Transmitted light-reflected scattered light retardation glass) was manufactured.
In addition, in addition to gold-cerium oxide-manganese dioxide, when various metal oxide colorants and decolorizers are further combined, the hue of the transmitted light-reflected scattered light retardation opal glass differs slightly due to solarization etc. I got it. As described above, in the present invention, the chemical composition of the base glass and the combination of the coloring agent are important new findings for producing transmitted light-reflected scattered light retardation opal glass. The present invention has been made based on this new knowledge. In the present invention, silicic acid-alumina-boron oxide-
Phosphoric acid - alkaline earth metal oxide - alkali metal oxide is the basic opal glass composition, and gold - cerium oxide - manganese dioxide is the basic coloring agent, but various metal oxide coloring agents can be used as necessary. Alternatively, a composite coloring agent in which a decolorizing agent is combined with gold and rare earth oxides is added and mixed. Next, the mixture is heated and melted, and then cooled to obtain a base glass. Then, the base glass is subjected to reheating treatment to cause phase separation. As a result, a transmitted light-reflected scattered light retardation opal glass having a unique coloration is obtained. [Example] The raw material composition of the basic opal glass of the general embodiment of the present invention, expressed in weight percent, is 10 to 70% shirasu, 0 to 60% feldspar, and 10 to 10% alumina.
20, boron oxide 2.5-15%, calcium phosphate dihydrate 0.1-6.0% ( _0.1-6.0 % as phosphoric acid _P2O5
5.0%), alkaline earth metal oxides from 10 to 25%, and alkali metal oxides from 3 to 10%. The mixing ratio of shirasu and feldspar, which are the silicic acid raw materials for glass, can be changed appropriately to adjust the degree of coloration, as the iron content in shirasu causes a dark coloration. Sum is 50-75
The silicic acid content is within the range of % by weight.
The content ranges from 30 to 60% by weight. To explain the reason for setting the above basic opal glass composition range, if the sum of shirasu-feldspar is less than 50% or more than 75%, the basic glass composition will be low silicic acid or high silicic acid, and phase separation will result from reheating treatment. It deviates from this range and does not result in the color development of the present invention. Alumina is partially contained in shirasu and feldspar, but if the alumina content in the basic glass, which is added for the purpose of suppressing phase separation and increasing the viscosity of the glass, is less than 10%, phase separation occurs too quickly. This does not lead to the color development of the invention. Also, the alumina content is 20%
Above this, phase separation is suppressed and the color development of the present invention is not achieved. Boron oxide and phosphoric acid are added as phase splitting agents for the basic glass. When boron oxide is near the upper limit in the above composition range, phosphoric acid is near the lower limit, and when phosphoric acid is near the upper limit, boron oxide is added. It is necessary to set the composition ratio near the lower limit,
They are added in an antagonistic manner. Does phase separation occur when boron oxide is less than 2.5% and phosphoric acid is less than 0.1%?
Even if phase separation occurs, the coloring of the present invention does not occur. If the content is 15% or more of boron oxide and 5.0% or more of phosphoric acid, the color development of the present invention cannot be achieved because phase separation occurs too quickly and emulsion occurs. The alkaline earth metal oxide has the function of promoting phase separation of the basic glass, but if it is less than 10%, phase separation will not occur, and if it is more than 25%, phase separation will occur too quickly, resulting in emulsion and the coloration of the present invention. It won't happen. Alkali metal oxides are contained in shirasu and feldspar, and are added as necessary for the purpose of reducing the viscosity of the base glass. When the alkali metal oxide content is less than 3%, the viscosity of the glass is high and the operability of the molten glass is poor, and when it is more than 10%, phase separation does not occur and the coloration of the present invention is not achieved. In addition, the amount of gold added as a red coloring agent is 0.002
~0.2% by weight. Gold addition amount 0.002%
Below, the color development due to reheating of the base glass does not lead to the color development of the present invention. If it exceeds 0.02%, gold lumps will form in the basic glass, making it uneconomical. On the other hand, cerium oxide as a coloration aid is 0.1
-2.0% by weight, manganese dioxide 0.1-2.0% by weight. If each amount is less than 0.1% by weight, the coloration will be insufficient and the coloration of the present invention will not be achieved, and if it is more than 2.0% by weight, the coloration will be dark and unsuitable for use as craft glass. In the embodiments described above, shirasu and feldspar are primarily used as sources of silicic acid and alumina in the base glass, but common glass raw materials can also be used. That is, it is also possible to use anhydrous silicic acid, silica sand, aluminum oxide, kaolin, spodumene, etc. as the silicic acid and alumina source. As the boron oxide source, boric anhydride, boric acid, etc. can be used. As the phosphoric acid source, calcium phosphate, magnesium phosphate, phosphoric anhydride, etc. can be used. Alkaline earth oxides include calcium sources,
Magnesium oxide sources etc. are used. As the calcium source, calcium oxide, calcium carbonate, calcium fluoride, calcium hydroxide, calcium salts, etc. can be used. Magnesium oxide, magnesium carbonate, and magnesium salts can be used as magnesium oxide sources. When shirasu and feldspar are used as in the above embodiment, an alkali metal oxide can be obtained from shirasu and feldspar. However, when shirasu and feldspar are not used, sodium,
It is necessary to add each carbonate or borate of potassium and iron oxide in an amount corresponding to the iron content in Shirasu. It is possible to use a combination of various metal oxide colorants and decolorants to give subtle changes in hue, and zirconium oxide or titanium oxide can be added to give the glass chemical durability. In addition, it is also possible to add fluorides such as calcium fluoride, sodium borofluoride, and soda silicate to improve the meltability of the glass. Table 1 shows an example of the composition of volcanic ash soil Shirasu.

[Table] As shown in Table 1, the chemical composition of volcanic ash soil shirasu varies depending on the production area, but when using shirasu as a raw material for glass, it is necessary to pay attention to the iron content that gives the glass its dark color. There is. In the present invention, feldspar, which has a low iron content and good solubility, is used in combination with the aim of adjusting the iron content in shirasu, which varies depending on the production area, and controlling the coloration of the final product. . The chemical composition of the feldspar used in the present invention is shown in Table 2.

〔Effect of the invention〕

According to the present invention, the transmitted light is bright green, blue,
It is possible to obtain a transmitted light-reflected scattered light hue contrast opal glass which has a blue-green-red mosaic color or red color and whose reflection and scattering ranges from dark red to brownish color. Further, since it is possible to use volcanic ash soil shirasu and feldspar as the main raw materials, it is possible to produce transmitted light-reflected scattered light hue contrast opal glass at low cost. The transmitted light-reflected scattered light hue difference opal glass obtained in the present invention can be used as decorative glass, craft glass,
It can be widely used in the field of glass industry such as glass for building materials, glass for tableware, glass for special bottles, etc., and the unused resource volcanic ash soil whitebait can be used effectively.

Claims (1)

[Claims] 1. 30-60% silicic acid, 10-20% alumina, 2.5-15% boron oxide, 0.1-5.0% phosphoric acid, 10-25% alkaline earth oxide by weight. things, and 3~
Basic opal glass raw material containing 10% alkali metal oxide, red coloring agent containing 0.002-0.02% gold by weight%,
and 0.1-2.0% cerium oxide and 0.1-2.0% by weight
A coloration aid containing 2.0% manganese dioxide is mixed, and the mixture is melted at a temperature between 1200 and 1500°C and then cooled to obtain a base glass, and the base glass is
Transmitted light characterized in that the base glass is colored by reheating at a temperature between 600 and 1000°C.
A method for producing reflective and scattered light hue contrast opal glass. 2. The method for producing transmitted light-reflected scattered light hue contrast opal glass according to claim 1, wherein the main raw materials for the basic opal glass raw materials are volcanic ash soil shirasu and feldspar. 3 by weight 30-60% silicic acid, 10-20% alumina, 2.5-15% boron oxide, 0.1-5.0% phosphoric acid, 10-25% alkaline earth oxide, and 3-
Basic opal glass raw material containing 10% alkali metal oxide, red coloring agent containing 0.002-0.02% gold by weight%,
and 0.1-2.0% cerium oxide and 0.1-2.0% by weight
A coloration aid containing 2.0% manganese dioxide is mixed, and the mixture is melted at a temperature between 1200 and 1500°C and then cooled to obtain a base glass, and the base glass is
A transmitted light-reflected scattered light hue difference opal glass produced by reheating the base glass at a temperature between 600 and 1000°C to develop color. 4. The transmitted light-reflected scattered light hue difference opal glass according to claim 3, wherein the main raw materials of the basic opal glass raw materials are volcanic ash soil shirasu and feldspar.