JPH0573703B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for producing red opal glass, which is mainly used in the field of decoration. [Conventional technology] Conventional opal glass contains various fluorides, chlorides,
It is manufactured by using oxides such as phosphates, tin, zirconium, titanium, and antimony as opacifying agents, and by heat treatment of phase-splitting glass such as borosilicate soda glass. In addition, the present inventor has already developed a phase-splitting glass using volcanic ash soil shirasu as one of the raw materials, which can be used for decoration by separating the phases through heat treatment ( (See Patent Application Publication No. 141639 of 1988). These opal glasses can be given a color unique to the colorant by adding various colorants, but in particular, opal glasses made from volcanic ash soil shirasu with a red color have not been manufactured to date. do not have. [Problems to be Solved by the Invention] The present inventor attempted to produce a red-colored opal glass using a normal coloring method based on the above-mentioned opal glass that the present inventor had already developed, but failed. It ended successfully. Therefore, as a result of continuing research, we discovered that red-colored opal glass can be produced within a specific composition range of basic glass by adding a combination of gold and rare earth element oxides, and we decided to invent this production method. I've reached it. [Means for Solving the Problems] The method for producing red opal glass according to the present invention includes 30 to 60% silicic acid, 5 to 20% alumina, 2.5 to 20% boron oxide, and 10 to 25% by weight. Basic opal glass raw material consisting of alkaline earth oxides and 2-10% alkali metal oxides, wt%
A red coloring agent containing 0.002 to 0.02% gold in weight percent, and a coloring aid containing 0.25 to 4.0% rare earth element oxide in weight percent, and the mixture is 1200 to 1500
After melting at a temperature between 600 and 1000 °C, the base glass is obtained by cooling, and the base glass is reheated at a temperature between 600 and 1000 °C to cause phase separation of the base glass and color development of the gold colloid. It is characterized by [Example] The basic opal glass composition is 30 to 30% by weight.
60% silicic acid, 5~20% alumina, 2.5~20
% boron oxide, 10-25% alkaline earth oxides, and 2-10% alkali metal oxides. The red colorant contains 0.002-0.02% gold by weight. The coloring aid is 0.25 to 0.25% by weight.
Contains 4.0% rare earth element oxides. It is preferable to use volcanic ash soil shirasu and feldspar as the main raw materials for the opal glass composition. a basic opal glass composition, a red colorant,
After mixing with the coloring aid, the above raw material mixture is
After melting at a temperature between 1200 and 1500℃, the melt is cooled in a mold and molded, or after cooling, it is cut into appropriate sizes and heated to 800 to 1000℃ to form the desired shape. Obtain transparent light tan base glass as
The base glass is reheated at a temperature between 600 and 1000°C to cause phase separation of the base glass and color development of the gold colloid, thereby obtaining a red opal glass. The specific temperature and time of the reheating are determined empirically and are related to the heat capacity of the base glass being treated and the desired color tone and degree of phase separation. In the present invention, phase separation means separation into two phases exhibiting an amorphous macroscopic pattern. In the manufacturing method of the present invention, in addition to volcanic ash shirasu and feldspar, for example, alumina, boron oxide, sodium carbonate, calcium carbonate, magnesium oxide, etc. are used as the opal glass composition. As the red colorant, water gold or the like is used. As the coloring aid, cerium oxide, neodymium oxide, yttrium oxide, etc. are used. It can also be used as a color erasing agent using complementary colors if necessary.
An appropriate amount of vanadium oxide, manganese dioxide, etc. may be added. Also, to improve opacity,
Appropriate amounts of common opacifying agents such as fluorides, zirconium oxide, titanium oxide, etc. may be added. Tables 1 and 2 show examples of the composition of volcanic ash soil shirasu and feldspar, respectively.

【table】

〔Effect of the invention〕

According to the present invention, it is possible to produce red-colored opal glass used for decoration etc. using inexpensive volcanic ash soil shirasu and feldspar as main raw materials.

Claims (1)

[Claims] 1. 30-60% silicic acid, 5-20% alumina, 2.5-20% boron oxide, 10-25% alkaline earth oxide, and 2-10% alkali by weight. Basic opal glass raw material consisting of metal oxides, red colorant containing 0.002-0.02% gold by weight%,
and a coloring aid containing 0.25 to 4.0% by weight of rare earth element oxide, 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 method for producing red opal glass, which comprises reheating at a temperature between 600 and 1000°C to cause phase separation of the basic glass and color development of gold colloid. 2. The method for producing red 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.