JPS62226821A - glass manufacturing method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a glass manufacturing method for equalizing the composition of lumps and stabilizing the formation of lumps in the sol-gel method, which is one of the glass manufacturing methods. Regarding.

[Conventional technology]

Conventionally, glass production using the sol-gel method has been limited to the formation of small lumps, and has been limited to the formation of larger lumps wJ? ! - In order to obtain this, metal oxide fine powder with the same composition as that at the time of gel formation, or fine powder consisting of other gold m* compounds, is either mixed together at the time of hydrolysis or added after hydrolysis. There is.

[Problems to be solved by the present invention]

However, in the conventional method, the fine powder tends to be unevenly distributed due to agglomeration, resulting in a non-uniform composition, and the formation of large lumps is unstable.Furthermore, the method for uniform dispersion is complicated. The drawback was that it was difficult to stabilize the process.

The present invention aims to solve all of these conventional problems by making it easier to uniformly disperse fine powder and to stably obtain large lumps. Furthermore, the purpose is to improve the purity by facilitating the removal of foreign substances in the fine powder by filtering, etc.〇 [Means for solving all problems] In order to solve the above problems, the glass manufacturing method of the present invention After mixing the fine powder in advance with an aqueous solution that improves the dispersion ratio the most, the pH value? ! -Adjust and diversify the profit from 50 to 7.0,
Metal alkoxide and acid catalyst are all added and hydrolyzed, and glass is formed by sintering from sol to gel.
Features.

[Effect]

As mentioned above, by dispersing submicron to several hundred micron metal/oxide fine powder in an aqueous solution of PH1O to ZO in advance, it can be easily purified and hydrolyzed with a homogeneous composition if necessary. It becomes possible.

[Example 1] The present invention will be described in detail below based on Examples.

Fine particulate anhydrous silica having a primary particle size of approximately 400 A was mixed with 3 tons of pure water at a ratio of 55%. At this point, the pH was 58. The average particle size α was 30 μ by stirring, and after 2 hours of ultrasonic dispersion (600 W), the average particle size was reduced to 1 (115 μ), and then impurities were removed through a 5 μ filter. Next, the ethyl silicate was dissolved in 1/6 of pure water. In order to accelerate hydrolysis and suppress grain growth, 11N-hydrochloric acid was added at 20 CO and hydrolysis was carried out. Hydrolysis was completed after about 1 hour, and the average particle size was α16μ. To promote gelation while stirring, a basic α1N ammonia water was gradually added dropwise to adjust the pH to 4.0, and the mixture was left in a 20 cm square polypropylene container for 30 hours to gel, then 10% of the internal volume was added. A hole was made in the lid and the lid was gradually heated to 70°C over 5 days to dry.Meanwhile, for comparison, 1 mol of ethyl silicate and 6 mol of pure water were added in advance, and 0.I
N salt #1 was added for hydrolysis, and under pH 2.5, fine particulate silica was gradually added at a ratio of 55%, and the above-mentioned ultrasonic dispersion was carried out for a total of 2 hours. At this time, the average particle size was 121 μm, which was poor. It was then dried using the same process as above. Yet another method is to
t-55'A, pure water and hydrochloric acid, and fine particulate anhydrous silica t-55'A
They were mixed all at once so that the particles were hydrolyzed, and the particle size was measured to be 120 μm. Thereafter, they were dried in the same manner.

The dried dry gel is in the form of a lump of fine particulate silica that has been previously dispersed in pure water and then hydrolyzed -> no cracks in the lump.

After hydrolysis, fine particulate silica was added → 60% lumps cracked, and particulate silica was added at the same time as hydrolysis → lumps cracked 40%.

Based on the above results, we further focused on the PR when fine particulate anhydrous silica was dispersed in pure water, and the results confirmed by PI (value and dispersion particle size check 2s 5X silica amount) are as follows.

By sintering at 1200° C. after drying, colorless and transparent quartz glass was obtained, and no cracking occurred during sintering.

[Example 2] Fine powder of zirconium oxide is mixed with caulked pure water,
By ultrasonic dispersion, an average particle diameter of 1 (118 μm, 176 moles of ethyl silica) was added to pure water, and hydrolysis was carried out under 1N hydrochloric acid with stirring. After the hydrolysis was completed, in order to promote gelation, the pH was adjusted to 4.5 with 1 L normal ammonia water, gelled in a polypropylene container, and dried at 90°C. On the other hand, after the above-mentioned ethyl silicate)k hydrolysis, the entire fine powder of zirconium oxide was added and dispersed by intense stirring and ultrasonication.

At this time, the average particle size did not decrease below 121 μm.

This is thought to be due to the fact that the cracking of the lumps due to drying was clearly more likely to occur when zirconium oxide was added later, and segregation was rare. Moreover, the latter case partially exhibited foaming due to sintering.

〔Effect of the invention〕

As explained above, the present invention involves dispersing fine powder in water and then hydrolyzing it with gold 4 alkoxide to stably produce particles on a homogeneous large lump. This can be achieved by setting the diameter to +1 at the lowest point and leaving it straight in that state, and the present invention is an extremely effective means.

that's all

Claims (1)

[Claims] In the sol-gel method in which metal alkoxides are produced by hydrolysis, metal oxide fine powder is preheated to a pH of 3.0 to
A glass manufacturing method in which glass is dispersed in 7.0 water, then a metal alkoxide and an acid catalyst are added, and the glass is formed by hydrolysis.