JPH0421614B2 - - Google Patents
Info
- Publication number
- JPH0421614B2 JPH0421614B2 JP21862484A JP21862484A JPH0421614B2 JP H0421614 B2 JPH0421614 B2 JP H0421614B2 JP 21862484 A JP21862484 A JP 21862484A JP 21862484 A JP21862484 A JP 21862484A JP H0421614 B2 JPH0421614 B2 JP H0421614B2
- Authority
- JP
- Japan
- Prior art keywords
- quartz glass
- base material
- glass base
- porous quartz
- porous
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 62
- 239000000463 material Substances 0.000 claims description 53
- 238000010438 heat treatment Methods 0.000 claims description 20
- 238000001354 calcination Methods 0.000 claims description 13
- 238000009826 distribution Methods 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 7
- 238000010304 firing Methods 0.000 claims description 4
- 239000011521 glass Substances 0.000 claims description 3
- 230000007547 defect Effects 0.000 description 12
- 238000005245 sintering Methods 0.000 description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 238000004017 vitrification Methods 0.000 description 9
- 239000007789 gas Substances 0.000 description 8
- 239000002344 surface layer Substances 0.000 description 8
- 238000000034 method Methods 0.000 description 7
- 150000003377 silicon compounds Chemical class 0.000 description 6
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 229910052734 helium Inorganic materials 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 239000010453 quartz Substances 0.000 description 3
- 239000005049 silicon tetrachloride Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 238000010574 gas phase reaction Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910003902 SiCl 4 Inorganic materials 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 239000012159 carrier gas Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- AIFMYMZGQVTROK-UHFFFAOYSA-N silicon tetrabromide Chemical compound Br[Si](Br)(Br)Br AIFMYMZGQVTROK-UHFFFAOYSA-N 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- ZDHXKXAHOVTTAH-UHFFFAOYSA-N trichlorosilane Chemical compound Cl[SiH](Cl)Cl ZDHXKXAHOVTTAH-UHFFFAOYSA-N 0.000 description 1
- 239000005052 trichlorosilane Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B19/00—Other methods of shaping glass
- C03B19/14—Other methods of shaping glass by gas- or vapour- phase reaction processes
- C03B19/1453—Thermal after-treatment of the shaped article, e.g. dehydrating, consolidating, sintering
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/012—Manufacture of preforms for drawing fibres or filaments
- C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
- C03B37/01446—Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Glass Melting And Manufacturing (AREA)
Description
【発明の詳細な説明】
「技術分野」
本発明は、気相反応合成法によつて製造された
多孔質石英ガラス母材を加熱炉中で加熱して透明
合成石英ガラスを得るための多孔質石英ガラス母
材のガラス化方法に関する。Detailed Description of the Invention [Technical Field] The present invention relates to a porous quartz glass base material produced by a gas phase reaction synthesis method, which is heated in a heating furnace to obtain a transparent synthetic quartz glass. This invention relates to a method for vitrifying a quartz glass base material.
「従来技術およびその問題点」
従来より、合成石英ガラスを製造する方法の一
つとして、気相反応法により多孔質石英ガラス母
材を形成し、この母材を加熱してガラス化する方
法が採用されている。すなわち、バーナーから珪
素化合物、水素、酸素等の原料ガスを鉛直に懸下
した種棒に向けて供給し、四塩化珪素等の珪素化
合物を酸水素炎中で加水分解させ、石英製等の種
棒の下端部にシリカ微粒子を付着、堆積させて多
孔質石英ガラス母材を形成する。そして、この多
孔質石英ガラス母材を加熱炉に入れ、ヒーターで
加熱して母材を焼結することによりガラス化する
方法である。"Prior art and its problems" Conventionally, one method for producing synthetic quartz glass is to form a porous quartz glass base material by a gas phase reaction method, and then heat this base material to vitrify it. It has been adopted. That is, a raw material gas such as a silicon compound, hydrogen, or oxygen is supplied from a burner toward a vertically suspended seed rod, and the silicon compound such as silicon tetrachloride is hydrolyzed in an oxyhydrogen flame. Fine silica particles are attached and deposited on the lower end of the rod to form a porous quartz glass matrix. Then, this porous quartz glass base material is placed in a heating furnace and heated with a heater to sinter the base material, thereby vitrifying it.
この方法により大口径の合成石英ガラスを製造
しようとする場合、大口径のバーナーを用いる
が、バーナーから出る火炎は中心部は高温である
がその外周は中心部より温度が低い状態となり、
かかる温度の違いにより、多孔質石英ガラス母材
の外周部の密度はその中心部より低くなる傾向に
ある。例えば、上記方法により径250mmの円柱状
の多孔質石英ガラス母材を製造した場合、より低
い温度でSiO2微粒子が付着する外周部の密度は
0.10〜0.15ｇ／c.c.となる一方、中心部の密度は
0.30〜0.40ｇ／c.c.程度となる。かかる密度分布を
持つた多孔質石英ガラス母材を加熱炉へ入れて
1400〜1600℃に加熱してガラス化すると、ガラス
化した石英ガラス母材の中心部は気泡等の欠点が
無いものの、その表面から５〜10mmの表面層に数
10μm程度の径の気泡等の欠点が多数発生すると
いう欠点が見出された。かかる欠点発生の１つの
原因としては、多孔質石英ガラス母材を焼結して
ガラス化する際、密度の低い外周部分の方の収縮
が先に起る故、ガラス化する際に発生するガスの
除去が不充分となり、ガラス化した石英ガラス母
材の表面層に残存するものと認められる。また、
他の原因としては、密度に低い外周部分に一部密
度の高いシリカ粒子が入り込み、周辺と均一にガ
ラス化せず異質なものとして欠点となると考えら
れる。上記したような多孔質石英ガラス母材の径
方向の密度分布を一定にして母材の収縮を均一化
ならしめ、欠点の発生を防ぐことも考えられる
が、火炎の温度分布を均一にすることが困難であ
り、径方向に密度分布の一定した多孔質母材を得
ることははなはだ困難である。 When attempting to manufacture large-diameter synthetic quartz glass using this method, a large-diameter burner is used, but the flame emitted from the burner is hot at the center, but the temperature at the outer periphery is lower than the center.
Due to this temperature difference, the density of the outer periphery of the porous quartz glass base material tends to be lower than that of the center. For example, when a cylindrical porous quartz glass base material with a diameter of 250 mm is manufactured by the above method, the density of the outer periphery where SiO 2 fine particles adhere at a lower temperature is
0.10~0.15g/cc, while the density in the center is
It will be about 0.30 to 0.40 g/cc. A porous quartz glass base material with such a density distribution is placed in a heating furnace.
When vitrified by heating to 1,400 to 1,600℃, the center of the vitrified quartz glass base material has no defects such as bubbles, but there are several defects in the surface layer 5 to 10 mm from the surface.
A drawback was found that a large number of defects such as bubbles with a diameter of about 10 μm were generated. One reason for the occurrence of such defects is that when the porous quartz glass base material is sintered and vitrified, the outer periphery, which has a lower density, shrinks first, so the gas generated during vitrification occurs. It is recognized that the removal of the silica glass was insufficient and that it remained on the surface layer of the vitrified quartz glass base material. Also,
Another reason is that some high-density silica particles enter the outer circumference where the density is low, and the vitrification is not uniform with the surrounding area, resulting in a defect as foreign matter. It is possible to make the radial density distribution of the porous quartz glass base material constant as described above to make the shrinkage of the base material uniform and prevent the occurrence of defects, but it is also possible to make the temperature distribution of the flame uniform. It is extremely difficult to obtain a porous base material with a constant density distribution in the radial direction.
「発明の目的及び概要」
本発明は、上記従来技術の問題点を解決し、大
口径の多孔質石英ガラス母材をガラス化しても、
得られた石英ガラス中に気泡等の欠点が含まれな
いようにした多孔質石英ガラス母材のガラス化方
法を提供することを目的として研究の結果発明さ
れたものであり、その要旨は、石英ガラス製造用
種棒の一端に堆積、成長させた多孔質石英ガラス
母材を加熱して透明ガラス化して合成石英ガラス
を製造する方法において、予め多孔質石英ガラス
母材を1100〜1300℃で仮焼して該母材の径方向の
密度布を整えた後、1400〜1600℃で焼成し透明ガ
ラス化することを特徴とする合成質石英ガラス製
造方法に関するものである。"Objective and Summary of the Invention" The present invention solves the problems of the prior art described above, and even when a large-diameter porous quartz glass base material is vitrified,
It was invented as a result of research with the aim of providing a method for vitrifying a porous quartz glass base material so that the resulting quartz glass does not contain defects such as air bubbles. In a method of manufacturing synthetic quartz glass by heating a porous quartz glass base material deposited and grown on one end of a seed rod for glass production to make it transparent, the porous quartz glass base material is preheated at 1100 to 1300°C. The present invention relates to a method for producing synthetic quartz glass, which comprises firing to adjust the density distribution in the radial direction of the base material, and then firing at 1,400 to 1,600°C to form transparent glass.
「発明の構成」
本発明において、多孔質石英ガラス母材は、例
えば、第１図に示したような装置により製造され
る。"Structure of the Invention" In the present invention, a porous quartz glass base material is manufactured by, for example, an apparatus as shown in FIG.
すなわち、ボンベ１およびボンベ２から水素お
よび酸素がフローコントローラー３，４を通して
多重管バーナ５に供給される。また、四塩化珪
素、トリクロロシラン、四臭化珪素等の珪素化合
物のガスが、タンク６からポンプ７により熱交換
器８を通して多重管バーナ５に供給される。 That is, hydrogen and oxygen are supplied from cylinders 1 and 2 to multi-tube burner 5 through flow controllers 3 and 4. Further, a gas of a silicon compound such as silicon tetrachloride, trichlorosilane, silicon tetrabromide, etc. is supplied from the tank 6 to the multi-tube burner 5 by a pump 7 through a heat exchanger 8.
多重管バーナ５は反応室９内において酸水素炎
を形成し、珪素化合物を加水分解してシリカ微粒
子を生成する。なお、図示されていないが、窒
素、アルゴンなどの不活性ガスもバーナー５に供
給され、これらは珪素化合物のキヤリヤガスとし
て、あるいは酸水素炎中のエアーカーテンとして
利用される。この加水分解反応を珪素化合物が四
塩化珪素である場合について化学式で示すと次の
ようになる。 The multi-tube burner 5 forms an oxyhydrogen flame in the reaction chamber 9 and hydrolyzes the silicon compound to produce silica fine particles. Although not shown, inert gases such as nitrogen and argon are also supplied to the burner 5, and these are used as a carrier gas for silicon compounds or as an air curtain in an oxyhydrogen flame. The chemical formula for this hydrolysis reaction when the silicon compound is silicon tetrachloride is as follows.
2H2＋O2→2H2O …１）
SiCl4＋2H2O→SiO2＋4HCl …２）
このシリカ微粒子が反応室９で鉛直に懸下され
た石英製の種棒１０の下端部に付着、堆積して、
順次成長し、大口径（例えば径20cm〜35cm）の多
孔質石英ガラス母材１１が形成される。なお、反
応によつて発生するHClはNaOH液の貯槽１２か
ら循環されるNaOH液と洗浄塔１３で向流接触
して吸収除去される。 2H 2 +O 2 →2H 2 O …1) SiCl 4 +2H 2 O→SiO 2 +4HCl …2) These silica particles adhere and accumulate on the lower end of the quartz seed rod 10 suspended vertically in the reaction chamber 9. do,
The porous quartz glass base material 11 is grown sequentially and has a large diameter (for example, a diameter of 20 cm to 35 cm). Note that HCl generated by the reaction is absorbed and removed by contacting the NaOH liquid circulated from the NaOH liquid storage tank 12 in countercurrent contact with the NaOH liquid in the washing tower 13.
本発明においては、上記した方法により製造さ
れた多孔質石英ガラス母材が、1400〜1600℃の焼
成によりガラス化する前に、予め1100〜1300℃の
範囲において仮焼して多孔質石英ガラス母材を径
方向の密度分布を整える。この仮焼はHeガスを
少なくとも50％以上含む雰囲気下、加熱炉におい
て上記温度域において行なう。仮焼の時間は仮焼
温度及び多孔質石英ガラス母材の大きさ、密度等
にもよるが、１〜10時間が適当である。かかる仮
焼を行なつた多孔質石英ガラス母材は、同一の加
熱炉において、又、別の加熱炉に移して、直ち
に、又は所定時間をおいて本焼結し、ガラス化さ
せる。この本焼結は、Heガスを少なくとも80％
含む加熱炉において1400〜1600℃の温度域におい
て行なう。本焼結の時間も、多孔質石英ガラス母
材の大きさ、密度等にもよるが、１〜５時間が適
当である。 In the present invention, the porous quartz glass base material produced by the above-described method is pre-calcined in the range of 1100-1300°C before being vitrified by firing at 1400-1600°C. Adjust the radial density distribution of the material. This calcination is performed in a heating furnace in an atmosphere containing at least 50% He gas in the above temperature range. The calcination time depends on the calcination temperature, the size and density of the porous quartz glass base material, and is suitably 1 to 10 hours. The porous quartz glass base material subjected to such calcination is transferred to the same heating furnace or another heating furnace, and is subjected to main sintering and vitrification immediately or after a predetermined period of time. This main sintering uses He gas at least 80%
It is carried out in a heating furnace containing a temperature range of 1400 to 1600°C. The time for main sintering also depends on the size, density, etc. of the porous quartz glass base material, but is suitably 1 to 5 hours.
多孔質石英ガラス母材の仮焼及び本焼結におい
ては、多孔質石英ガラス母材の下端から加熱して
徐々に仮焼及び本焼結を行なうのが最適である。 In the calcination and final sintering of the porous quartz glass base material, it is optimal to gradually perform the calcination and final sintering by heating from the lower end of the porous quartz glass base material.
このように、多孔質石英ガラス母材を下端部か
ら加熱して仮焼及び本焼結によるガラス化を行な
うようにしたので、種棒の下端部近傍が最初に軟
化することなくなり、仮焼、本焼結が終了するま
で母材を落下させることなく支持することができ
る。また、種棒の熱変形を防止して繰り返しの使
用に耐えるようにすることができる。さらに、ガ
ラス化に伴なつて流出する気泡は、まだガラス化
されていない母材の上部へ逃げることができるの
で、得られた石英ガラス中に気泡が含有されるこ
とを防止できる。 In this way, since the porous quartz glass base material is heated from the lower end to perform vitrification through calcination and final sintering, the vicinity of the lower end of the seed rod does not soften first, and the calcination and The base material can be supported without falling until the main sintering is completed. Further, the seed rod can be prevented from being thermally deformed and can withstand repeated use. Furthermore, the air bubbles that flow out during vitrification can escape to the upper part of the base material that has not yet been vitrified, so that it is possible to prevent air bubbles from being contained in the obtained quartz glass.
又、本発明の仮焼又は本焼結においては、母材
の加熱は多孔質石英ガラス母材を回転させながら
加熱炉に上方から徐々に挿入し、種棒の下端部加
熱炉内のヒーターの上端より少し手前になつた時
点で停止させることによつて行なうようにするの
が最適である。このように加熱すれば、母材を種
棒に支持した状態でそのまま仮焼、ガラス化する
ことができ、回転させることにより加熱を平均し
て行なうことができ、種棒の近傍を加熱しないよ
うにして母材の落下や種棒の熱変形を確実に防止
できる。 In addition, in the calcination or main sintering of the present invention, the base material is heated by gradually inserting the porous quartz glass base material into the heating furnace from above while rotating it, and placing the seed rod at the lower end of the heater in the heating furnace. It is best to do this by stopping a little before the top. By heating in this way, the base material can be calcined and vitrified as it is while being supported by the seed rod, and heating can be evened out by rotating, so that the vicinity of the seed rod is not heated. This can reliably prevent the base material from falling and the seed rod from being deformed by heat.
更に、本焼結用の加熱炉内のヒーターには上部
から下部に向けて高まる温度勾配が設けられてい
るようにするのが好ましい。このようにすれば、
多孔質石英ガラス母材をヒーター中に挿入するに
際し、母材の温度を徐々に高めていくようにし
て、加熱効率を向上させることができる。なお、
温度勾配は、多孔質石英ガラス母材のガラス化温
度が1410℃以上であることから、ヒーターの上部
を1200℃前後、中間部を1430℃前後、下部を1400
℃前後とするのが適当である。 Furthermore, it is preferable that the heater in the heating furnace for main sintering is provided with a temperature gradient that increases from the top to the bottom. If you do this,
When inserting the porous quartz glass base material into the heater, heating efficiency can be improved by gradually increasing the temperature of the base material. In addition,
Since the vitrification temperature of the porous quartz glass base material is 1410°C or higher, the temperature gradient is approximately 1200°C at the top of the heater, around 1430°C at the middle, and 1400°C at the bottom.
It is appropriate to set it at around ℃.
「発明の実施例」
第１図に示した装置を利用して製造された石英
製の種棒に形成された円柱状の多孔質石英ガラス
母材｛直径は25cm、長さは60cm、中心部（中心か
ら径１cmの部分）の平均密度は0.40ｇ／c.c.、表面
部（表面層から２cmの部分）の平均密度は0.12
ｇ／c.c.｝を1250℃に保持され、Heガスを60％含
有する雰囲気にコントロールされた加熱炉内に上
方から入れて密封し、５時間保持し、仮焼を行な
つた。この仮焼後の多孔質石英ガラス母材は半透
明化しており、中心部の平均密度は0.5ｇ／c.c.、
表面部の平均密度は0.42ｇ／c.c.であつた。"Embodiments of the Invention" A cylindrical porous quartz glass base material formed on a quartz seed rod manufactured using the apparatus shown in Fig. 1 {diameter: 25 cm, length: 60 cm, central portion The average density of the area (1 cm in diameter from the center) is 0.40 g/cc, and the average density of the surface area (2 cm from the surface layer) is 0.12
g/cc} was maintained at 1250° C., and placed in a heating furnace controlled to have an atmosphere containing 60% He gas, sealed, and held for 5 hours to perform calcination. After calcining, the porous quartz glass matrix becomes translucent, with an average density of 0.5 g/cc at the center.
The average density of the surface area was 0.42 g/cc.
仮焼を行なつた後、直ちに第２図に示すよう
に、石英製の種棒１０付きの仮焼した多孔質石英
ガラス母材１１を、内部にヘリウムガス90％と
N2ガス10％が導入され、内部に環状のヒーター
２２が配置されている加熱炉２１内に上方から挿
入した。このヒーター２２は、この多孔質石英ガ
ラス母材１１が挿入できる大きさを有するものが
使用され、又、ヒーター２２は上部が1200℃程
度、中間部が1430℃程度、下部が1400℃程度とな
るように温度勾配を設けた。種棒１０を図中矢印
で示す如く回転しながら下降させ、多孔質石英ガ
ラス母材１１をその下端部からヒーター２２内に
徐々に挿入した。この、多孔質石英ガラス母材１
１は、下端部から徐々に加熱溶融し、脱泡がなさ
れて透明ガラス化し、母材１１よりも径の小さい
石英ガラス２３となつた。 Immediately after calcining, as shown in FIG. 2, the calcined porous quartz glass base material 11 with a seed rod 10 made of quartz is filled with 90% helium gas inside.
It was inserted from above into a heating furnace 21 into which 10% N 2 gas was introduced and an annular heater 22 was arranged inside. The heater 22 used has a size that allows the porous quartz glass base material 11 to be inserted therein, and the temperature of the heater 22 is approximately 1200°C at the top, approximately 1430°C at the middle, and approximately 1400°C at the bottom. A temperature gradient was established. The seed rod 10 was lowered while rotating as shown by the arrow in the figure, and the porous quartz glass base material 11 was gradually inserted into the heater 22 from its lower end. This porous quartz glass base material 1
1 was gradually heated and melted from the lower end, defoamed, and became transparent vitrified to become quartz glass 23 having a smaller diameter than the base material 11.
このようにしたガラス化した石英ガラス母材
は、その表面層（５mm厚）から内側の中心部には
欠点の発生はなく、又、この表面層に発生した気
泡も表面積１cm2当り平均1.3個と少なかつた。一
方、仮焼を行なわずに同上の方法により焼成しガ
ラス化した石英ガラス母材は、その表面層（１cm
厚）から内側の中心部には欠点の発生はなかつた
ものの、この表面層に発生した表面積１cm2当り平
均10個と多量であつた。 The thus vitrified quartz glass base material has no defects in the inner center from its surface layer (5 mm thick), and the number of bubbles generated in this surface layer is on average 1.3 per 1 cm 2 of surface area. There were very few. On the other hand, the surface layer (1 cm
Although no defects were found in the inner center of the layer (thickness), a large number of defects occurred on the surface layer, an average of 10 defects per 1 cm 2 of surface area.
「発明の効果」
以上説明したように、本発明によれば、多孔質
石英ガラス母材を本焼結によるガラス化処理前
に、予め仮焼した多孔質石英ガラス母材の径方向
の密度分布の均一化をはかつているので、本焼結
によるガラス化処理を行なつてもその中心部は勿
論、その表面層部分に発生する欠点数を著しく低
下することができ、品質の向上、歩留の向上が得
られる。"Effects of the Invention" As explained above, according to the present invention, the density distribution in the radial direction of the pre-calcined porous quartz glass base material is obtained before the vitrification treatment by main sintering. As a result, the number of defects that occur not only in the center but also in the surface layer can be significantly reduced even when vitrification treatment is performed by main sintering, resulting in improved quality and yield. can be improved.
特に、大口径の多孔質石英ガラス母材のガラス
化に本発明の方法は最適である。 In particular, the method of the present invention is most suitable for vitrifying large-diameter porous quartz glass base materials.
第１図は多孔質石英ガラス母材を得るための装
置の一例を示す説明図、第２図は本発明によるガ
ラス化方法の実施例を示す説明図、である。
図中、１０は種棒、１１は多孔質石英ガラス母
材、２１は加熱炉、２２はヒーター、２３は石英
ガラスである。
FIG. 1 is an explanatory diagram showing an example of an apparatus for obtaining a porous quartz glass base material, and FIG. 2 is an explanatory diagram showing an example of the vitrification method according to the present invention. In the figure, 10 is a seed rod, 11 is a porous quartz glass base material, 21 is a heating furnace, 22 is a heater, and 23 is quartz glass.
Claims (1)
せた多孔質石英ガラス母材を加熱して透明ガラス
化して合成石英ガラスを製造する方法において、
予め多孔質石英ガラス母材を1100〜1300℃で仮焼
して該母材の径方向の密度分布を整えた後、1400
〜1600℃で焼成し透明ガラス化することを特徴と
する合成質石英ガラスの製造方法。1. A method for producing synthetic quartz glass by heating a porous quartz glass base material deposited and grown on one end of a seed rod for producing quartz glass to make it transparent vitrified,
After pre-calcining the porous quartz glass base material at 1100 to 1300℃ to adjust the density distribution in the radial direction of the base material,
A method for producing synthetic quartz glass, which is characterized by firing at ~1600°C and turning it into transparent glass.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21862484A JPS6197141A (en) | 1984-10-19 | 1984-10-19 | Preparation of synthetic quartz glass |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21862484A JPS6197141A (en) | 1984-10-19 | 1984-10-19 | Preparation of synthetic quartz glass |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6197141A JPS6197141A (en) | 1986-05-15 |
| JPH0421614B2 true JPH0421614B2 (en) | 1992-04-13 |
Family
ID=16722868
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21862484A Granted JPS6197141A (en) | 1984-10-19 | 1984-10-19 | Preparation of synthetic quartz glass |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6197141A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0337119A (en) * | 1989-07-03 | 1991-02-18 | Shinetsu Sekiei Kk | Production of heat-resistant synthetic quartz glass |
-
1984
- 1984-10-19 JP JP21862484A patent/JPS6197141A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6197141A (en) | 1986-05-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6763682B1 (en) | Process and apparatus for manufacturing a glass ingot from synthetic silica | |
| US6319550B1 (en) | Method and apparatus for treating silica granules using porous graphite crucible | |
| CN1012641B (en) | Method for fabricating articles which include high silica glass bodies and articles formed thereby | |
| JPS5844619B2 (en) | Manufacturing method of optical fiber base material | |
| CN103118995A (en) | Process for producing a quartz glass crucible having a transparent inner layer of synthetically produced quartz glass | |
| JPH07121813B2 (en) | Method for producing flat quartz glass | |
| JPH0421614B2 (en) | ||
| JP2001089166A (en) | Production of tube type silica glass | |
| JPH0478567B2 (en) | ||
| JP2001163629A (en) | Thermal insulator for semiconductor, processing furnace and producing method thereof | |
| JPS6272536A (en) | Production of high-purity quartz glass | |
| JPH09202632A (en) | Production of cylindrical quartz glass | |
| JPS605030A (en) | High purity glass powder and apparatus and method for manufacturing glass products thereby | |
| JPS6324937B2 (en) | ||
| JP2002154838A (en) | Method for manufacturing glass preform for optical fiber | |
| US6923021B2 (en) | Method and apparatus for fused silica production | |
| JPS59184734A (en) | Transparent vitrification process of optical porous glass | |
| JPH0563415B2 (en) | ||
| JP3036993B2 (en) | Manufacturing method of synthetic quartz glass member | |
| JP2542514B2 (en) | Manufacturing method of synthetic quartz glass | |
| JP2002249342A (en) | Glass body and method for manufacturing it | |
| JPH0232668Y2 (en) | ||
| JPS6238291B2 (en) | ||
| WO2004101457A1 (en) | Process for producing glass parent material of optical fiber | |
| JP2611684B2 (en) | Manufacturing method of quartz glass |