JPS6270236A - Production of glass tube - Google Patents

Abstract

PURPOSE:To produce high-quality glass tubes in high mass productivity without causing deformation of tubular gel immediately after gelatinization, by rotating a cylindrical container packed with gel to gelatinize the sol, filling a space part of the container with liquid, drying and sintering it. CONSTITUTION:Ethyl silicate is blended with hydrochloric acid and silica fine powder, irradiated with ultrasonic wave, centrifuged and filtered to give gel, which is packed into a cylindrical container and gelatinized while being rotated around the shaft of the cylinder, to form tubular gel. Then, a space part of the container is filled with liquid (e.g., mixed solution of ethanol and water) containing a sol component and the tubular gel is dried and sintered. Consequently, a glass tube having an inner diameter with high degree of circularity free from warpage and crack can be inexpensively produced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Area of Application] Kiwaaki relates to a method for manufacturing glass tubes by a sol-gel method.

[Summary of the invention]

In the present invention, the sol is placed in a cylindrical container and gelled while rotating around the tube axis to create a tubular gel, and then dried.
In a method for manufacturing glass tubes using the sol-gel method, in which glass tubes are vitrified by sintering, some liquid is left in the space of the cylindrical container after gelation. By applying light, there is no deformation of the tubular gel during gelling and contraction, and there is no external damage.
What about roundness, warpage, and yield by relaxing s? This is an improvement.

[Conventional technology]

The glass manufacturing method using the sol-gel method is currently attracting a lot of attention because it allows high-quality glass to be manufactured at low cost.

Also, put the sol in a cylindrical container, gel it while rotating it around the tube axis to create a tubular gel, and dry it to make a dry gel. A method for manufacturing glass tubes in which glass tubes are vitrified by sintering is very important as a method for manufacturing high-quality glass tubes at low cost. In the method of making a tubular gel by gelling while rotating, the inward direction of the tubular gel becomes a free surface due to centrifugal force during the gelling process, so a very precise cylindrical shape can be obtained.
In addition, a very small surface roughness σ) can be obtained, and furthermore, these are not affected by the shape of the 'B vessel used for rotation.
Because of this, it is possible to manufacture glass tubes with excellent non-N precision at each station. Currently, when the sol gels, the rotation is stopped, and when the tubular gel has shrunk to the extent that the tubular gel can be removed from the cylindrical container, it is transferred to a drying container and dried. Since deterioration in the distance between the cylinders is observed, the cylindrical container is continued to be rotated even after gelation, and when the gel is confirmed to have hardened to a certain extent, the rotation is stopped and the conventional process is carried out. .

[Problems and objects to be solved by the invention] However, in the above-mentioned rice promotion Mtm, the gel is soft immediately after gelation, and the resulting gel is deformed in the tube, and by the time it is dried, the gel is soft. Circularity and cylindricity deteriorate. And this dark distortion is preserved, and in the subsequent drying and Akatsukicho process, -
The #-shaped gel may curl or crack. Furthermore, even with a method devised to improve this problem, in which the cylindrical container continues to be rotated fully even after gelation, the disadvantage is that a large amount of tube is consumed and the equipment deteriorates due to long-term use of the rotating machine. Ta. The present invention is intended to solve these problems, and its purpose is to eliminate the deformation of tubular gel immediately after gelation, and to manufacture glass tubes that can be easily obtained from high-quality glass tubes. The whole method is there to offer.

[Means to solve all problems]

The method for manufacturing a quartz glass tube of the present invention includes a method for manufacturing a quartz glass tube using the sol-gel method, and includes the steps of: pouring all the liquid into the space of a cylindrical container after gelation; be a sign. It is not preferable to use a material that can rapidly draw out water and ethanol, which are the constituent liquids of the wet gel.

[Effect]

Immediately after gelation, gel is soft and deformable like rubber, but is it liquid? By filling with light, the shadow of the military sword 111i1? is suppressed to &l' of the gel and due to the buoyancy of the liquid while the gel is contracting. The roundness r will not be decreased and the roundness r will not be deteriorated. Therefore, a glass tube with an inner diameter of very good roundness can be obtained. In addition, since the gel is soft from immediately after gelation to drying, there is no distortion of the tubular gel (σ), which reduces the possibility of warping or scraping during the drying and sintering process. Also, the liquid may be affected by external fluctuations (shock, temperature, etc.)
It plays the role of a buffer zone. Also, since the tubular gel is immersed in the water, dirt from the walls of the 1st circle @ 60q can be prevented. In this way, 9 yields are pastured, and the lIl' productivity is significantly the same as above. Also, does it have the same effect as above? In order to obtain liquid, it is only necessary to shine the liquid into a dia-shaped container, so it is less expensive and less expensive than the method of rotating rice.
It's Tn Hi. As described above, according to the present invention, high-quality glass Aokura Hitomi can be obtained with good consideration.

[Example-1] Ethyl silica) (5i(00,H,), )900
d, 0.02N salt brew 7!50ml1. Imitation wood 7 Rika 500
Mix, stir vigorously, irradiate ultrasonic waves, centrifuge,
P-cycle was carried out and a sol with a high average purchase rate was obtained. In this sol, 0
．． After adding IN ammonia water and adjusting the pH to i5, pour it into a polypropylene cylindrical container measuring 1400+++/'z5cWIφX1m, and add 1100ml around the tube axis.
When rotated at 00 Orp, gelation occurred after 1 hour. After gelation, a sample in which a cylindrical tube was filled with a mixture of ethanol:water = -1:1 (volume ratio) and 2:1 with only ethanol, acetone, and glycerin. 20 of each were created. For comparison, 20 samples were prepared in which rotation was stopped immediately after gelation, and 20 samples in which rotation was continued for 3 hours and 5 hours in IB# darkness at 11,000 rpm after gelation. The obtained tubular gel was dried for two weeks at 60°C, and the obtained dried gel '11300
When heated to ℃, a 2.5-φXSOα quartz glass tube was obtained.

Table 1 (8:) The roundness and warpage are the average values of the crushed quartz glass tubes. From Table 1, the samples that continued to rotate even after gelation were
It can be seen that roundness, warpage, and yield are all clearly omitted. Also, compared to the method of continuing rotation after gelation, the results are almost the same in terms of roundness, warpage, and yield.

[Example-2] Ethyl silicate 900-10.02N Hydrochloric acid 76〇-
Complete mixing, vigorous stirring, ultrasonic irradiation, centrifugation, and f-filtration produce a highly homogeneous sol. Obtained. Add 0.1N ammonia water to this sol, adjust the pH to 5, and filter it to 1400sgi5. Pour into a φX1ss polypropylene cylindrical S vessel and rotate around the tube axis at 1000 rp.
When rotated at m, it gelled in one hour. The rotation of this gel is completely stopped and it is filtered as it is in the cylindrical tube, the rotation is continued as it is, or the rotation is stopped [
7. Place the adult body in the space inside the cylindrical tube (ethanol:water = 1:1
A total of 20 bottles of three samples were prepared, each filled with a mixed sweet liquid. Stop the rotation completely and circle li! The gels broke into small pieces on average after 2 days in the gels that were left in the same state within f, and after 4 days on average in the gels that were continued to be rotated. However, the sample containing liquid 'r:f' in the space inside the cylindrical tube did not crack during drying. Dry gel 11 dried at 60℃ for 2 weeks
When heated to 300'c, a quartz glass tube of 2.5 Mφ x 50 pores was used.

[Example-5] Silica sol ligation was performed using the same method as in Example-1, and the PHj was directly applied to the retina at 4.
The mixture was placed in a polypropylene cylindrical container 6 and rotated around the tube axis at 800 rpm, resulting in gelation after 6 hours. After gelation, there are 8 cylindrical vessels! Between ethanol and water (
1:1 volume ratio) All 20 samples with mixed Mr elements BL
T, ta. For comparison, the rotation was stopped immediately after gelation, and the rotation was continued at 800 rpm for 5th 8th rotation even after gelation.
A broken sample? 20 of each were created. Obtained tubular dulke 6
It was dried at 0°C for 2 weeks to form a dry gel. The obtained dry gel i1! When heated to 500℃, 2.51MX5
0m of quartz glass "#" was spilled.

The gelation process in Table 2 is relatively slow, and immediately after gelation, the tubular gel is very soft. is large. From table @2, the sample whose cylindrical tube was filled with liquid after gelation had roundness,
Both warpage and yield were clearly improved, and the values were almost the same as those of the sample in which gelation was followed by rolling.

〔Effect of the invention〕

As described above, according to the present invention, the sol is placed in a cylindrical container, gelled while rotating around the tube axis to create a tubular gel, and then vitrified by drying and sintering. In the method for manufacturing glass tubes by the method, after gelation, by injecting an acid into each cylindrical space, the deformation of the α-shaped gel in the gelled straight bond is eliminated due to the buoyancy of the adult σ). Roundness, warpage, and yield are all important factors.

In addition, compared to the method of continuing rotation after gelation, which achieves similar effects, it saves temperature, pipework, and prevents machine deterioration.
It is an IT rudder. Therefore, glass tubes of commercial quality and ladle size can be easily produced, and can be applied in many directions, and quartz glass tubes are sometimes used as core tubes in diffusion furnaces for semiconductors, jacket tubes for original fibers, etc. We believe that this method can be widely applied to other applications. For the quartz glass tube, σ
), but it goes without saying that the same applies to glass tubes made of other components.

that's all

Claims (2)

[Claims] (1) In a method for producing glass tubes using the sol-gel method, in which a sol is placed in a cylindrical container, gelled while rotating around the tube axis to create a tubular gel, and then vitrified by drying and sintering. A method for manufacturing a glass tube, which comprises filling a space in a cylindrical container with a liquid after gelation. (2) The method for manufacturing a glass tube according to claim 1, wherein the liquid filling the space of the cylindrical container is a liquid containing a sol component.