JPS62283833A - Production of glass tube - Google Patents

Abstract

PURPOSE:To obtain the title high-quality glass tube appropriate for a semiconductor furnace core tube, etc., with good productivity by performing a sol preparation stage and a gelation stage in the same pipe to save time and tools in case of producing a glass tube by a sol-gel method. CONSTITUTION:Ethyl silicate, hydrochloric acid, fine silica powder, etc., are charged in a cylindrical vessel 1, a lid is put on, the vessel is fixed to a turning gear 5 and rotated to carry out hydrolysis, and a sol is prepared. Aq. ammonia, etc., are then added to gelate the sol while continuing the rotation, and a cylindrical gel is produced. The obtained gel is taken out, dried, and then sintered to obtain the desired quartz tube. Since the sol preparation stage and gelation stage are thus performed in the same vessel, the time and efforts necessary for the movement of a sol can be saved, the deterioration in the freshness of a sol can be prevented, and a high-quality glass tube can be obtained.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method of manufacturing a glass tube by a sol-gel method.

[Conventional technology]

The conventional sol-gel method for manufacturing glass tubes is organized as follows:
As described in t20672, a metal alkoxide solution is hydrolyzed using hydrochloric acid as a catalyst, silica fine powder is added to the hydrolyzed solution, and stirring and ultrasonic irradiation are repeated to create a homogeneous sol. Ta. After adjusting the pH of the sol with a base such as aqueous ammonia so that it gels in a certain gelation time, it is transferred to a cylindrical container and placed around the axis of the tube for 10 minutes.
000 (G = 980 cm/sec2) or less at a rotational speed that exerts a centrifugal force to form a centrifugal gel, thereby obtaining a cylindrical gel. A glass tube was obtained by drying and sintering this gel.

[Problem that the invention seeks to solve]

However, the above-mentioned conventional technology requires a lot of effort, tools, and time in the sol preparation process and gelation process. As for the tools, the container for sol preparation and the container for centrifugal gelation must be separate. In addition, it takes time and effort to transfer the sol to these containers. As a result, the freshness of the sol decreases, and there are many opportunities for impurities to be mixed in. Therefore, the present invention is intended to solve these problems, and its purpose is to minimize the amount of labor, tools, and time required in the sol preparation process and gelation process, and to manufacture glass tubes with good mass productivity. It's about doing.

[Means for solving problems]

The method for manufacturing a glass tube of the present invention includes a step of preparing a sol solution,
A method for manufacturing a glass tube comprising a gelling step, a gel drying step, and a gel sintering step is characterized in that the sol solution preparation step and gelling step are performed in the same pipe.

〔Example〕

Hereinafter, the present invention will be described in detail based on examples.

In a cylindrical container with a diameter of 48+n and a length of 199 cm, 1525 g of ethyl silicate (Si(OCz Hs)4) was placed.
, water 884g, salt tj12 cc, jg powder silica S
Put 360 g of i Ot into it, cover it with tape to a transparent acrylic plate with 51 holes in the center, attach it to the pipe, and then attach it to a rotating device as shown in Figure 1,
Rotation was started at a rotation speed of 0 rpm. At this time, there was intense agitation inside the pipe. It is known in advance that at the above ratio of raw materials, hydrolysis will be completed in about 20 minutes. However, in order to ensure that the fine powdered silica is sufficiently dispersed,
After hydrolysis, rotation was continued for 1 hour and 30 minutes in this state. After that, the rotation speed was increased to aoorpm. At this point, the liquid inside is in a somewhat agitated state, but the 0 rotation speed is the state where the sol inside does not come out even if the hole in the acrylic plate is made.
After increasing to orpm, 0. 60c of IN ammonia water
c Injected through the hole in the acrylic plate. Maintain the speed at 800 rpm for 5 minutes so that the ammonia water is mixed into the sol, then turn the speed at 1200 rpm.
Increased the speed to RPM. At 12 oorpm, the sol inside became a perfect circle and was rotating. Since it is known in advance that the gelation time of this sol is about 40 minutes, the sol inside will have been gelled 35 minutes after the rotation speed is increased to 1200 rpm. After gelation, 3
Rotation was continued at 1200 rpm, and after waiting until the gel became sufficiently hard, rotation was stopped, the pipe was removed from the rotating device, and the gel was aged in a ripening chamber at 30 degrees Celsius for 5 days, after which the gel was taken out from the purifier. The gel had shrunk to 185 cm. This gel was dried at 60°C for 3 weeks, and after drying, sintering was performed under a certain program to obtain a quartz tube with an outer diameter of 24 fl, an inner diameter of 12 fl, and a length of 98 aw. Ta. This tube showed no inferiority in quality compared to quartz tubes made by conventional methods. Also, it took much less effort, tools, and time to make the tube.

〔Effect of the invention〕

As described above, according to the present invention, in the method for manufacturing glass tubes by the sol-gel method, the sol solution preparation step and gelling step are performed in the same pipe, which saves a lot of effort, tools, and time. Glass tubes can be manufactured with good mass productivity. The glass tube produced by the sol-gel method thus obtained is of very good quality and can be widely used as a jacket tube for glass fibers, a furnace core tube for semiconductors, etc.

[Brief explanation of drawings]

FIG. 1 shows a schematic diagram of the mounting W used in the present invention. 1... Cylindrical container 2...Motor 3...Bearing 4...Fixing jig 5...Support stand 6... Injection container 7・・・・・・Cylinder that's all

Claims (1)

[Claims] A glass tube manufacturing method comprising a sol solution preparation step, a gelling step, a gel drying step, and a gel sintering step, wherein the sol solution preparation step and gelling step are performed in the same pipe. Method of manufacturing tubes.