JPH05319849A - Production of silica porous preform - Google Patents
Production of silica porous preformInfo
- Publication number
- JPH05319849A JPH05319849A JP12443592A JP12443592A JPH05319849A JP H05319849 A JPH05319849 A JP H05319849A JP 12443592 A JP12443592 A JP 12443592A JP 12443592 A JP12443592 A JP 12443592A JP H05319849 A JPH05319849 A JP H05319849A
- Authority
- JP
- Japan
- Prior art keywords
- silica
- burner
- base material
- diameter
- 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.)
- Pending
Links
Classifications
-
- 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]
- C03B37/01413—Reactant delivery systems
- C03B37/0142—Reactant deposition burners
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/60—Relationship between burner and deposit, e.g. position
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は気相軸付け法（ＶＡＤ
法）によりシリカ多孔質母材を製造する方法に関するも
のであり、特にシリカ多孔質母材の外径変動や変形を抑
えて、側面部にヒビ割れや剥離を発生させずにシリカ多
孔質母材を高収率かつ高合成速度で製造する方法に関す
るものである。ＶＡＤ法により製造されたシリカ多孔質
母材を焼結することにより石英ガラスが得られ、この石
英ガラスは高純度，高品質の石英ガラスとして高温耐熱
材、光学材、電子部品材料等の用途に用いられる。BACKGROUND OF THE INVENTION The present invention relates to a vapor phase axial method (VAD).
Method) for producing a silica porous base material, and in particular, suppressing the outer diameter variation and deformation of the silica porous base material without causing cracking or peeling on the side surface of the silica porous base material. The present invention relates to a method for producing a high yield and a high synthesis rate. Quartz glass is obtained by sintering a silica porous base material produced by the VAD method. This quartz glass is used as high-purity, high-quality quartz glass for high-temperature heat-resistant materials, optical materials, electronic component materials, etc. Used.
【０００２】[0002]
【従来の技術】一般に、ＶＡＤ法によるシリカ多孔質母
材は、気体のシリカ原料，可燃性ガス，不活性ガス及び
支燃性ガスをバーナーに供給して、火炎加水分解させて
シリカ微粒子を生成し、このシリカ微粒子を石英製等の
出発部材上に付着，堆積させ、シリカ微粒子の堆積速度
に応じて出発部材を引上げて、引上げ軸方向にシリカ微
粒子を堆積，成長をさせることにより製造されている。
気体のシリカ原料として四塩化珪素や三塩化シラン等の
珪素化合物が、可燃性ガスとして水素ガスが、支燃性ガ
スとして酸素ガスが、不活性ガスとして窒素ガス又はア
ルゴンガスが一般的に用いられる。2. Description of the Related Art Generally, a silica porous base material prepared by the VAD method supplies a gaseous silica raw material, a combustible gas, an inert gas, and a combustion-supporting gas to a burner to cause flame hydrolysis to produce fine silica particles. It is manufactured by depositing and depositing the silica fine particles on a starting member such as quartz, pulling up the starting member according to the deposition rate of the silica fine particles, and depositing and growing the silica fine particles in the pulling axial direction. There is.
Generally, silicon compounds such as silicon tetrachloride and silane trichloride are used as a gaseous silica raw material, hydrogen gas is used as a combustible gas, oxygen gas is used as a combustion supporting gas, and nitrogen gas or argon gas is used as an inert gas. ..
【０００３】ＶＡＤ法によるシリカ多孔質母材の製造に
おいて、シリカ多孔質母材の成長面とバーナーとの位置
関係により、得られるシリカ多孔質母材の収率や合成速
度，径の変動等のシリカ多孔質母材の生産性や合成の安
定性に大きく影響を与える。このため、シリカ多孔質母
材の引上げ速度の制御や、バーナー位置の制御につい
て、種々の方法が提案されている。例えば、１）ガラス
微粒子堆積体の成長端面位置を検出する装置と、その検
出出力によりガラス微粒子の吹付ノズルからの成長端面
の距離を一定に保持するように制御する装置とを有する
ことにより、ガラス微粒子堆積体の外径変動や、ガラス
の屈折率のゆらぎ等を防止するための光ファイバー母材
製造装置（特公昭５５−２７０１８号）、２）火炎加水
分解反応によって火炎中に形成されるガラス微粒子の流
れを検出し、ガラス微粒子の流れの中心部に存在するダ
ークラインが多孔質ガラス体堆積面上に吹き付けられる
位置を制御することにより合成状態、堆積状態を制御す
ることにより得られる光ファイバーの屈折率分布の再現
性を向上させる光ファイバー用母材の製造方法（特公昭
５９−１０９３９号）、３）火炎中のダークライン延長
線と出発基材回転軸との交点からガラス微粒子集合体底
面までの長さを所定の値に保って、ガラス微粒子を堆積
させることにより、常に最適のドーパント濃度を維持し
て光ファイバーとしての伝送特性の良好なものを比較的
長期間製造するためのガラス微粒子集合体の製造方法
（特開昭５８−１１５０３６号）、４）火炎の回転する
多孔質母材を覆う部分の形状を調節して堆積状態を安定
化することにより、安定した収率で母材形状も良好に保
てる光ファイバー用母材の製造方法（特開昭６２−２６
０７２９号）などである。In the production of a porous silica preform by the VAD method, the yield, synthesis rate, diameter variation, etc. of the obtained porous silica preform are dependent on the positional relationship between the growth surface of the porous silica preform and the burner. It greatly affects the productivity and synthetic stability of the porous silica matrix. For this reason, various methods have been proposed for controlling the pulling rate of the porous silica preform and controlling the burner position. For example, 1) glass having a device for detecting the position of the growth end face of the glass particle deposit and a device for controlling the detection output to keep the distance of the growth end face from the spray nozzle of the glass particles constant Optical fiber base material manufacturing apparatus (Japanese Patent Publication No. 55-27018) for preventing fluctuations in the outer diameter of a particle deposit and fluctuations in the refractive index of glass, etc. 2) Glass particles formed in the flame by a flame hydrolysis reaction Refraction of the optical fiber obtained by controlling the synthetic state and the deposition state by detecting the flow of the glass particles and controlling the position where the dark line existing in the center of the flow of the glass particles is blown onto the deposition surface of the porous glass body. Manufacturing method of base material for optical fiber which improves reproducibility of rate distribution (Japanese Patent Publication No. 59-10939), 3) Dark line extension in flame By maintaining the length from the intersection of the line and the rotation axis of the starting substrate to the bottom surface of the glass particle aggregate to a predetermined value and depositing glass particles, the optimum dopant concentration is always maintained and the transmission characteristics as an optical fiber are maintained. Of fine glass particles for producing relatively good long-term glass (Japanese Patent Laid-Open No. 58-115036), 4) Depositing by adjusting the shape of the portion covering the rotating porous base material of the flame. By stabilizing the state, a method for producing a base material for an optical fiber which can maintain a good shape of the base material with a stable yield (JP-A-62-26).
0729) and the like.
【０００４】これらの方法は、ＶＡＤ法により光ファイ
バー用の多孔質母材を製造するための方法であり、光フ
ァイバー用の多孔質母材としては、その収率や合成速度
の低下よりも、多孔質母材の外径変動や屈折率分布の変
動を伴うような合成の不安定性や非再現性が非常に問題
となるため、これらの問題点を特に低減させるための方
法である。すなわち、多孔質母材の外径変動や屈折率分
布の変動を防止すべくシリカ多孔質母材の引上げ速度や
バーナー位置を高度に制御するために、シリカ多孔質母
材の位置とバーナーの位置を精度良く検出しつつ、シリ
カ多孔質母材の引上げ速度とバーナーの位置の両者を微
調整するものである。そのため、シリカ多孔質母材位置
の制御機構とバーナー位置の制御機構を別個に必要とさ
れるため、装置の大型化、高級化がシリカ多孔質母材の
製造における経済性の面で問題となっている。また、合
成途上でバーナー位置を微調整する必要があるため、反
応炉のバーナー設置部分の気密性に問題が生じ、反応炉
の気密が十分でない場合には火炎の不安定化に伴う合成
状態の悪化、不純物の混入等の問題が生じる。These methods are methods for producing a porous base material for an optical fiber by the VAD method, and as a porous base material for an optical fiber, the porous base material is more porous than the yield and the decrease in synthesis rate. Since the instability and non-reproducibility of the synthesis accompanied by the fluctuation of the outer diameter of the base material and the fluctuation of the refractive index distribution are very problematic, this is a method for reducing these problems. That is, in order to highly control the pulling rate and the burner position of the silica porous base material in order to prevent the fluctuation of the outer diameter and the refractive index distribution of the porous base material, the position of the silica porous base material and the position of the burner are controlled. It is possible to finely adjust both the pulling rate of the porous silica preform and the position of the burner while accurately detecting Therefore, since the control mechanism for the silica porous base material position and the control mechanism for the burner position are required separately, upsizing and upsizing of the device become a problem in terms of economical efficiency in manufacturing the silica porous base material. ing. In addition, since it is necessary to finely adjust the burner position during the synthesis, there is a problem with the airtightness of the burner installation part of the reaction furnace, and if the airtightness of the reaction furnace is not sufficient, the synthesis state due to destabilization of the flame Problems such as deterioration and mixing of impurities occur.
【０００５】これに対し、石英ガラス用のシリカ多孔質
母材は、光ファイバー用の多孔質母材と異なり屈折率分
布については問題とされず、石英ガラス用のシリカ多孔
質母材の製造方法においては、石英ガラスを効率良く経
済的に生産するためには、より大型のシリカ多孔質母材
を収率良く高合成速度で製造する必要があると同時に、
石英ガラス製造の生産性や経済性を重視して作業性や操
作性、装置の簡略化が必要とされる。On the other hand, the silica porous preform for quartz glass does not pose a problem with respect to the refractive index distribution, unlike the porous preform for optical fibers, and in the method for producing the silica porous preform for quartz glass. In order to produce quartz glass efficiently and economically, it is necessary to produce a larger silica porous matrix at a high yield and at the same time,
Workability, operability, and simplification of the equipment are required with an emphasis on productivity and economic efficiency in manufacturing quartz glass.
【０００６】このため、石英ガラス用のシリカ多孔質母
材を製造する際に、シリカ多孔質母材の大型化や合成速
度の高速化を図る場合、一般的にはバーナーの大型化，
供給ガス流量の増大等が行われている。For this reason, when manufacturing a silica porous base material for quartz glass, in order to increase the size of the silica porous base material and increase the synthesis rate, generally, the burner is increased in size,
The supply gas flow rate is being increased.
【０００７】[0007]
【発明が解決しようとする課題】しかしながら、単にバ
ーナーの大型化や供給ガス流量の増大だけでは供給した
シリカ原料に対する反応収率が低下したり、シリカ多孔
質母材の外径が過度に肥大化するため、シリカ多孔質母
材の外径変動や変形を生じたり、シリカ多孔質母材の側
面部にヒビ割れや剥離が生じる例が多くなった。シリカ
多孔質母材の外径変動や変形は、安定な反応や合成が行
われていないために生じるものであり、合成収率の低下
と同時に変形度は合成を続ける限り著しくなるため、合
成は中止せざるを得ない。また、シリカ多孔質母材側面
部に生じるヒビ割れや剥離も一旦これらが生じた場合、
合成を続ける限り連鎖的に大きくなり、剥離片がバーナ
ー口内に落下する等により合成を継続することは難し
い。However, simply increasing the size of the burner or increasing the flow rate of the supply gas lowers the reaction yield with respect to the supplied silica raw material and excessively enlarges the outer diameter of the silica porous matrix. Therefore, there are many cases in which the outer diameter of the porous silica base material is fluctuated or deformed, or the side surface of the porous silica base material is cracked or peeled. The outer diameter fluctuation and deformation of the silica porous matrix are caused by the stable reaction and synthesis not being performed. I have no choice but to cancel. In addition, if these cracks or peeling occur on the side surface of the porous silica base material once they occur,
As long as the synthesis is continued, the size increases in a chained manner, and it is difficult to continue the synthesis because the peeled pieces fall into the burner mouth.
【０００８】さらに、ヒビ割れや剥離が生じたシリカ多
孔質母材を焼結処理して得られる石英ガラスには、その
表面や内部にヒビ割れや構造的欠陥を有しており、石英
ガラスの用途、例えば高温耐熱材、光学材、電子部品材
料等の用途には適さないか又は適する部分のみを切出し
て加工しても、著しく歩留りが悪くなる。Further, the silica glass obtained by sintering the silica porous base material having cracks and peeling has cracks and structural defects on the surface and inside, and The yield is remarkably deteriorated even if the portion which is not suitable for the use such as high temperature heat resistant material, optical material, electronic component material or the like is cut out and processed.
【０００９】本発明は以上のような問題点に鑑みてなさ
れたものであり、その目的は、ＶＡＤ法による石英ガラ
スの製造におけるその生産性と経済性の向上を目的とし
て、シリカ多孔質母材の外径変動や変形及びシリカ多孔
質母材側面部に生じるヒビ割れや剥離を発生させずに大
型のシリカ多孔質母材を高収率かつ高合成速度で製造す
る方法を提供するものである。The present invention has been made in view of the above problems, and an object thereof is to improve the productivity and the economical efficiency of the silica glass production by the VAD method. The present invention provides a method for producing a large-sized silica porous base material at a high yield and a high synthesis rate without causing the outer diameter variation and deformation of the silica porous body and the cracking and peeling of the side surface of the silica porous base material. ..
【００１０】[0010]
【課題を解決するための手段】本発明者らは、上記した
課題を解決するために鋭意検討した結果、バーナーの位
置をどのようにセッティングするかがシリカ多孔質母材
の収率とシリカ多孔質母材の変形や剥離と大きな関係が
あることに着目し、バーナーの大きさや供給ガス流量の
異なる場合においても、得られるシリカ多孔質母材に変
形や剥離の発生しない範囲で最高の収率を得るためにシ
リカ多孔質母材成長面とバーナーの最適な位置関係が存
在することを見出し、本発明を完成するに至ったもので
ある。すなわち、本発明はＶＡＤ法によるシリカ多孔質
母材の製造方法において、同芯円状多重管バーナーの口
径の１．８〜３．０倍の直径を有するシリカ多孔質母材
成長面疑似球の法線と該同芯円状多重管バーナーの中心
軸が一致するように該同芯円状多重管バーナーを固定設
置するシリカ多孔質母材の製造方法である。The inventors of the present invention have made earnest studies to solve the above-mentioned problems, and as a result, how to set the position of the burner depends on the yield of the silica porous matrix and the silica porosity. Focusing on the fact that there is a large relationship with the deformation and peeling of the base material, even if the burner size and supply gas flow rate are different, the highest yield is obtained within the range where the resulting porous silica base material does not undergo deformation or peeling. In order to obtain the above, it was found that there is an optimum positional relationship between the growth surface of the porous silica preform and the burner, and the present invention has been completed. That is, the present invention relates to a method for producing a porous silica preform by the VAD method, in which a silica porous preform growth surface pseudosphere having a diameter 1.8 to 3.0 times the diameter of a concentric circular multi-tube burner is used. This is a method for producing a porous silica preform in which the concentric circular multi-tube burner is fixedly installed so that the normal line and the central axis of the concentric circular multi-tube burner coincide with each other.
【００１１】以下、本発明についてさらに詳細に説明す
る。The present invention will be described in more detail below.
【００１２】本発明者らは、バーナーの設置位置とシリ
カ多孔質母材の成長面の関係について鋭意検討した結
果、シリカ多孔質母材の成長面の先端部はほぼ球状をな
していることを見出し、さらにバーナーの中心軸はこの
球面の中心を目指す位置関係、すなわち、この球面の法
線に一致していることを見出した。As a result of diligent studies on the relationship between the installation position of the burner and the growth surface of the silica porous base material, the present inventors have found that the tip of the growth surface of the silica porous base material is almost spherical. We also found that the central axis of the burner coincided with the positional relationship toward the center of this sphere, that is, the normal to this sphere.
【００１３】この球面のことをシリカ多孔質母材成長面
疑似球と呼ぶこととするが、このシリカ多孔質母材成長
面疑似球の直径はバーナーの設置位置により決定される
ものであり、シリカ多孔質母材成長面疑似球の直径を大
きくするような位置にバーナーを設置した場合、シリカ
多孔質母材の外径変動や変形、側面部にヒビ割れや剥離
が生じ、一方、シリカ多孔質母材成長面疑似球の直径を
小さくするような位置にバーナーを設置した場合には、
シリカ多孔質母材の収率や合成速度を著しく損うか又は
シリカ多孔質母材が変形する。そのため、同芯円状多重
管バーナーの設置は使用する同芯円状多重管バーナーの
口径の１．８〜３．Ｏ倍の直径を有するシリカ多孔質母
材成長面疑似球の法線と同芯円状多重管バーナーの中心
軸が一致する位置に設置することが、シリカ多孔質母材
の外径変動や変形、側面部に生じるヒビ割れや剥離を防
止して合成収率や合成速度を最も高くするものである。This spherical surface is called a silica porous base material growth surface pseudo sphere. The diameter of the silica porous base material growth surface pseudo sphere is determined by the burner installation position. When the burner is installed at a position that increases the diameter of the pseudo sphere on the growth surface of the porous base material, the silica porous base material fluctuates in outer diameter and is deformed, and the side surface is cracked or peeled. When a burner is installed at a position that reduces the diameter of the base material growth surface pseudosphere,
The yield or synthesis rate of the porous silica base material is significantly impaired or the porous silica base material is deformed. Therefore, the concentric circular multi-tube burner should be installed in the diameter range of 1.8-3. It is necessary to install it at a position where the normal line of the growth surface of the silica porous base material having a diameter of O times and the center axis of the concentric circular multi-tube burner coincide with the outer diameter variation or deformation of the silica porous base material. The cracks and peeling that occur on the side surface are prevented to maximize the synthetic yield and synthetic rate.
【００１４】さらに、本発明においては以上のような最
も適した位置に同芯円状多重管バーナーを固定設置する
ことから、同芯円状多重管バーナーとシリカ多孔質母材
の位置関係はシリカ多孔質母材先端部の位置を一定に保
つことにより得られ、同芯円状多重管バーナーの位置を
制御する必要がないため、バーナー本体の位置制御機構
を有する必要がなく、これによりバーナーを反応炉に設
置する部分の気密も保つことができ、反応の安定化に大
きく寄与する。また、シリカ多孔質母材先端部の位置を
一定に保つための制御機構は通常知られている光学的手
段による位置の検出とその検出信号を出発部材の引上げ
装置へフィードバックすることにより容易に達成され
る。Further, in the present invention, since the concentric circular multi-tube burner is fixedly installed at the most suitable position as described above, the positional relationship between the concentric circular multi-tube burner and the silica porous matrix is silica. It is obtained by keeping the position of the tip of the porous base material constant, and since it is not necessary to control the position of the concentric circular multi-tube burner, it is not necessary to have a position control mechanism for the burner body, which allows the burner to be The airtightness of the part installed in the reaction furnace can be maintained, which greatly contributes to stabilization of the reaction. Further, the control mechanism for keeping the position of the tip of the silica porous base material constant is easily achieved by detecting the position by a generally known optical means and feeding back the detection signal to the pulling device of the starting member. To be done.
【００１５】同芯円状多重管バーナーの中心軸とシリカ
多孔質母材中心軸のなす角をバーナー角度と呼ぶが、本
発明においてはバーナー角度はＶＡＤ法で一般的である
３０〜４５゜に設定することが本発明の効果、特にシリ
カ多孔質母材の外径変動や変形及び側面部のヒビ割れや
剥離を防止する上で好ましい。The angle formed by the central axis of the concentric circular multi-tube burner and the central axis of the porous silica preform is called the burner angle. In the present invention, the burner angle is 30 to 45 ° which is generally used in the VAD method. It is preferable to set it in order to prevent the effects of the present invention, in particular, the fluctuation and deformation of the outer diameter of the porous silica matrix material and the cracking and peeling of the side surface portion.
【００１６】本発明において使用される同芯円状多重管
バーナーとしては、中心層にガラス原料を供給する原料
供給用ノズルと、該原料供給用ノズルのまわりに火炎流
を形成する複数の火炎形成用ノズルを有するものであれ
ば特に限定するものではなく、例えば、４重管バーナ
ー、９重管バーナー、１３重管バーナー、１４重管バー
ナー等があげられる。As the concentric circular multi-tube burner used in the present invention, a raw material supply nozzle for supplying a glass raw material to the center layer and a plurality of flame forming means for forming a flame flow around the raw material supply nozzle. There is no particular limitation as long as it has a nozzle for use, and examples thereof include a quadruple tube burner, a nine-layer tube burner, a thirteen-layer tube burner, and a fourteen-tube burner.
【００１７】また、使用される同芯円状多重管バーナー
の口径は合成するシリカ多孔質母材の外径の大きさによ
り適宜選択すればよい。シリカ多孔質母材の外径と同芯
円状多重管バーナーの口径との関係は、シリカ多孔質母
材成長面疑似球の直径と同芯円状多重管バーナーの口径
との関係とほぼ同様な関係ではあるが、シリカ多孔質母
材の外側部に比較的緩く付着，堆積するシリカ微粒子の
層厚は排気条件により大きく変動するため、使用される
同芯円状多重管バーナーの口径は特に限定するものでは
ないが、シリカ多孔質の径は同芯円状多重管バーナーの
口径の２．８〜５．０倍になるのが通常であるため、合
成するシリカ多孔質母材の外径の０．２〜０．３５倍の
口径を有する同芯円状多重管バーナーを用いることが好
ましい。Further, the diameter of the concentric circular multi-tube burner used may be appropriately selected depending on the size of the outer diameter of the silica porous base material to be synthesized. The relationship between the outer diameter of the silica porous base material and the diameter of the concentric circular multi-tube burner is almost the same as the relationship between the diameter of the silica porous base material growth surface pseudosphere and the diameter of the concentric circular multi-tube burner. However, since the layer thickness of the silica fine particles that adhere and deposit relatively loosely on the outer side of the silica porous matrix varies greatly depending on the exhaust conditions, the diameter of the concentric multi-tube burner used is especially Although not limited, since the diameter of the silica porous material is usually 2.8 to 5.0 times the diameter of the concentric circular multi-tube burner, the outer diameter of the silica porous base material to be synthesized is not limited. It is preferable to use a concentric circular multi-tube burner having a diameter of 0.2 to 0.35 times.
【００１８】[0018]
【実施例】以下、本発明を実施例を用いてさらに説明す
るが、本発明はこれらに限定されるものではない。The present invention will be further described below with reference to examples, but the present invention is not limited thereto.
【００１９】実施例１ 図１に示すように、径が７９ｍｍの同芯円状多重管バー
ナーをバーナー仰角を４５゜にしてシリカ多孔質母材成
長疑似球の直径が２３０ｍｍとなるように固定設置し
た。このときシリカ多孔質母材疑似球の直径はバーナー
口径の２．９１倍であった。このバーナーに水素ガスを
２８４Ｎｌ／ｍｉｎ，酸素ガスを１０９Ｎｌ／ｍｉｎ，
窒素ガスを６２Ｎｌ／ｍｉｎ供給して酸水素火炎を形成
し、バーナーの中心層にガラス原料である四塩化珪素を
１０．０Ｎｌ／ｍｉｎ（４．５５ｋｇ／ｈｒ）を供給し
てシリカ多孔質母材の合成を行なったところ、収率７
０．８％，合成速度１８．９ｇ／ｍｉｎで外径が３１０
φのシリカ多孔質母材が得られた。このとき使用した同
芯円状多重管バーナーの口径は得られたシリカ多孔質母
材の０．２６倍であった。Example 1 As shown in FIG. 1, a concentric circular multi-tube burner having a diameter of 79 mm was fixedly installed so that the silica porous matrix growth pseudo sphere had a diameter of 230 mm with the burner elevation angle being 45 °. did. At this time, the diameter of the silica porous base material pseudo sphere was 2.91 times the burner diameter. In this burner, hydrogen gas is 284 Nl / min, oxygen gas is 109 Nl / min,
Nitrogen gas is supplied at 62 Nl / min to form an oxyhydrogen flame, and 10.0 Nl / min (4.55 kg / hr) of silicon tetrachloride, which is a glass raw material, is supplied to the central layer of the burner to provide a porous silica base material. Was synthesized, the yield was 7
0.8%, synthesis speed 18.9 g / min and outer diameter 310
A φ porous silica base material was obtained. The diameter of the concentric circular multi-tube burner used at this time was 0.26 times that of the obtained silica porous base material.
【００２０】実施例２ 径が８７ｍｍの同芯円状多重管バーナーをバーナー仰角
を４５゜にしてシリカ多孔質母材成長疑似球の直径が２
３０ｍｍとなるように固定設置した。このときシリカ多
孔質母材疑似球の直径はバーナー口径の２．６４倍であ
った。このバーナーに水素ガスを５１０Ｎｌ／ｍｉｎ，
酸素ガスを１５３Ｎｌ／ｍｉｎ，窒素ガスを６４Ｎｌ／
ｍｉｎ供給して酸水素火炎を形成し、バーナーの中心層
にガラス原料である四塩化珪素を１２．０Ｎｌ／ｍｉｎ
（５．４６ｋｇ／ｈｒ）を供給してシリカ多孔質母材の
合成を行なったところ、収率６８．４％，合成速度２
２．０ｇ／ｍｉｎで外径が３６０φのシリカ多孔質母材
が得られた。このとき使用した同芯円状多重管バーナー
の口径は得られたシリカ多孔質母材の０．２４倍であつ
た。Example 2 A concentric circular multi-tube burner having a diameter of 87 mm and a burner elevation angle of 45 ° had a silica porous matrix growth pseudo sphere having a diameter of 2.
It was fixedly installed so as to be 30 mm. At this time, the diameter of the silica porous base material pseudo sphere was 2.64 times the burner diameter. This burner was supplied with hydrogen gas at 510 Nl / min,
Oxygen gas 153 Nl / min, nitrogen gas 64 Nl / min
oxyhydrogen flame is formed by supplying min, and silicon tetrachloride, which is a glass raw material, is added to the center layer of the burner at 12.0 Nl / min.
(5.46 kg / hr) was supplied to synthesize the silica porous matrix, and the yield was 68.4% and the synthesis rate was 2.
A silica porous matrix having an outer diameter of 360φ was obtained at 2.0 g / min. The diameter of the concentric circular multi-tube burner used at this time was 0.24 times that of the obtained silica porous base material.
【００２１】実施例３ 径が８７ｍｍの同芯円状多重管バーナーをバーナー仰角
を６０゜にしてシリカ多孔質母材成長疑似球の直径が２
４０ｍｍとなるように固定設置した。このときシリカ多
孔質母材疑似球の直径はバーナー口径の２．７６倍であ
った。このバーナーに水素ガスを５１０Ｎｌ／ｍｉｎ，
酸素ガスを１５３Ｎｌ／ｍｉｎ，窒素ガスを６４Ｎｌ／
ｍｉｎ供給して酸水素火炎を形成し、バーナーの中心層
にガラス原料である四塩化珪素を１２．０Ｎｌ／ｍｉｎ
（５．４６ｋｇ／ｈｒ）を供給してシリカ多孔質母材の
合成を行なったところ、収率６９．９％，合成速度２
２．５ｇ／ｍｉｎで外径が３９０φのシリカ多孔質母材
が得られた。このとき使用した同芯円状多重管バーナー
の口径は得られたシリカ多孔質母材の０．２２倍であつ
た。Example 3 A concentric circular multi-tube burner having a diameter of 87 mm and a burner elevation angle of 60 ° was used, and the diameter of the silica porous matrix growth pseudo sphere was 2.
It was fixedly installed so as to be 40 mm. At this time, the diameter of the silica porous base material pseudo sphere was 2.76 times the burner diameter. This burner was supplied with hydrogen gas at 510 Nl / min,
Oxygen gas 153 Nl / min, nitrogen gas 64 Nl / min
oxyhydrogen flame is formed by supplying min, and silicon tetrachloride, which is a glass raw material, is added to the center layer of the burner at 12.0 Nl / min.
(5.46 kg / hr) was supplied to synthesize the porous silica matrix, and the yield was 69.9% and the synthesis rate was 2.
A silica porous base material having an outer diameter of 390φ was obtained at 2.5 g / min. The diameter of the concentric circular multi-tube burner used at this time was 0.22 times that of the obtained silica porous base material.
【００２２】実施例４ 径が５３ｍｍの同芯円状多重管バーナーをバーナー仰角
を４５゜にしてシリカ多孔質母材成長疑似球の直径が１
００ｍｍとなるように固定設置した。このときシリカ多
孔質母材疑似球の直径はバーナー口径の１．８９倍であ
った。このバーナーに水素ガスを１１８Ｎｌ／ｍｉｎ，
酸素ガスを５５Ｎｌ／ｍｉｎ，窒素ガスを２７Ｎｌ／ｍ
ｉｎ供給して酸水素火炎を形成し、バーナーの中心層に
ガラス原料である四塩化珪素を４．０Ｎｌ／ｍｉｎ
（１．８２ｋｇ／ｈｒ）を供給してシリカ多孔質母材の
合成を行なったところ、収率７８．０％，合成速度７．
８ｇ／ｍｉｎで外径が１８０φのシリカ多孔質母材が得
られた。このとき使用した同芯円状多重管バーナーの口
径は得られたシリカ多孔質母材の０．２９倍であった。 比較例１ 同芯円状多重管バーナーの中心軸とシリカ多孔質母材の
引上げ軸がねじれの位置になるように、同芯円状多重管
バーナーの固定設置を水平方向に同芯円状多重管バーナ
ーの口径の４分の１だけずらし、またシリカ多孔質母材
の成長面が同芯円状多重管バーナーの中心軸とシリカ多
孔質母材の引上げ軸の交点からシリカ多孔質母材成長面
疑似球の半径に相当する長さだけ下方に常に位置するよ
うにシリカ多孔質母材の引上げ制御装置の制御設定を行
なった。この同芯円状多重管バーナーに、気体のガラス
原料，可燃性ガス，不活性ガス及び支燃性ガスを供給し
て、シリカ多孔質母材の合成を行なった。その結果、得
られたシリカ多孔質母材の成長面は先端に凹部が生じて
球状ではなく、シリカ多孔質母材の側面形状も凹凸があ
り、一部に剥離が生じていた。Example 4 A concentric circular multi-tube burner having a diameter of 53 mm and a burner elevation angle of 45 ° was used, and the diameter of the silica porous matrix growth pseudosphere was 1.
It fixedly installed so that it might be set to 00 mm. At this time, the diameter of the silica porous base material pseudo sphere was 1.89 times the burner diameter. Hydrogen gas was added to this burner at 118 Nl / min,
Oxygen gas is 55 Nl / min, nitrogen gas is 27 Nl / m
Into supply oxyhydrogen flame, and silicon tetrachloride as a glass raw material is 4.0 Nl / min in the center layer of the burner.
(1.82 kg / hr) was supplied to synthesize the porous silica matrix, and the yield was 78.0% and the synthesis rate was 7.
A silica porous base material having an outer diameter of 180φ was obtained at 8 g / min. The diameter of the concentric circular multi-tube burner used at this time was 0.29 times that of the obtained silica porous base material. Comparative Example 1 The concentric circular multi-tube burner was fixedly installed in the horizontal direction so that the central axis of the concentric circular multi-tube burner and the pulling axis of the silica porous base material were in a twisted position. The diameter of the tube burner is shifted by 1/4, and the growth surface of the porous silica preform grows from the intersection of the central axis of the concentric multitube burner and the pulling axis of the porous silica preform. The control setting of the pulling-up control device for the silica porous base material was performed so that it was always positioned below by a length corresponding to the radius of the plane sphere. To this concentric circular multi-tube burner, a gaseous glass raw material, a flammable gas, an inert gas and a combustion-supporting gas were supplied to synthesize a porous silica preform. As a result, the growth surface of the obtained silica porous base material was not spherical with a concave portion formed at the tip, and the side surface shape of the porous silica base material was also uneven, with some peeling.
【００２３】比較例２ 図２に示すように、径が７９ｍｍの同芯円状多重管バー
ナーをバーナー仰角を４５゜にしてシリカ多孔質母材成
長疑似球の直径が２６５ｍｍとなるように固定設置し
た。このときシリカ多孔質母材疑似球の直径はバーナー
口径の３．３５倍であった。このバーナーに水素ガスを
２８４Ｎｌ／ｍｉｎ，酸素ガスを１０９Ｎｌ／ｍｉｎ，
窒素ガスを６２Ｎｌ／ｍｉｎ供給して酸水素火炎を形成
し、バーナーの中心層にガラス原料である四塩化珪素を
１０．０Ｎｌ／ｍｉｎ（４．５５ｋｇ／ｈｒ）を供給し
てシリカ多孔質母材の合成を行なったところ、１００分
後にシリカ多孔質母材側面部に剥離が生じたため、合成
を中止した。Comparative Example 2 As shown in FIG. 2, a concentric circular multi-tube burner having a diameter of 79 mm was fixedly installed with the burner elevation angle set to 45 ° so that the diameter of the silica porous matrix growth pseudosphere was 265 mm. did. At this time, the diameter of the silica porous base material pseudo sphere was 3.35 times the burner diameter. In this burner, hydrogen gas is 284 Nl / min, oxygen gas is 109 Nl / min,
Nitrogen gas is supplied at 62 Nl / min to form an oxyhydrogen flame, and 10.0 Nl / min (4.55 kg / hr) of silicon tetrachloride, which is a glass raw material, is supplied to the central layer of the burner to provide a porous silica base material. When the above synthesis was performed, peeling occurred on the side surface portion of the silica porous matrix after 100 minutes, so the synthesis was stopped.
【００２４】比較例３ 図３に示すように、径が７９ｍｍの同芯円状多重管バー
ナーをバーナー仰角を４５゜にしてシリカ多孔質母材成
長疑似球の直径が１１５ｍｍとなるように固定設置し
た。このときシリカ多孔質母材疑似球の直径はバーナー
口径の１．４６倍であった。このバーナーに水素ガスを
２８４Ｎｌ／ｍｉｎ，酸素ガスを１０９Ｎｌ／ｍｉｎ，
窒素ガスを６２Ｎｌ／ｍｉｎ供給して酸水素火炎を形成
し、バーナーの中心層にガラス原料である四塩化珪素を
１０．０Ｎｌ／ｍｉｎ（４．５５ｋｇ／ｈｒ）を供給し
てシリカ多孔質母材の合成を行なったところ、収率５
４．５％，合成速度１４．６ｇ／ｍｉｎで外径が２３０
φのシリカ多孔質母材が得られた。このとき使用した同
芯円状多重管バーナーの口径は得られたシリカ多孔質母
材の０．３４倍であった。Comparative Example 3 As shown in FIG. 3, a concentric circular multi-tube burner having a diameter of 79 mm was fixedly installed so that the silica porous matrix growth pseudo sphere had a diameter of 115 mm with a burner elevation angle of 45 °. did. At this time, the diameter of the silica porous base material pseudo sphere was 1.46 times the burner diameter. In this burner, hydrogen gas is 284 Nl / min, oxygen gas is 109 Nl / min,
Nitrogen gas is supplied at 62 Nl / min to form an oxyhydrogen flame, and 10.0 Nl / min (4.55 kg / hr) of silicon tetrachloride, which is a glass raw material, is supplied to the central layer of the burner to provide a porous silica base material. Was synthesized, yield 5
4.5%, synthetic speed 14.6 g / min and outer diameter 230
A φ porous silica base material was obtained. The diameter of the concentric circular multi-tube burner used at this time was 0.34 times that of the obtained silica porous base material.
【００２５】比較例４ 径が８７ｍｍの同芯円状多重管バーナーをバーナー仰角
を４５゜にしてシリカ多孔質母材成長疑似球の直径が１
４０ｍｍとなるように固定設置した。このときシリカ多
孔質母材疑似球の直径はバーナー口径の１．６１倍であ
った。このバーナーに水素ガスを５１０Ｎ１／ｍｉｎ，
酸素ガスを１５３Ｎｌ／ｍｉｎ，窒素ガスを６４Ｎｌ／
ｍｉｎ供給して酸水素火炎を形成し、バーナーの中心層
にガラス原料である四塩化珪素を１２．０Ｎｌ／ｍｉｎ
（５．４６ｋｇ／ｈｒ）を供給してシリカ多孔質母材の
合成を行なったところ、収率５５．５％，合成速度１
７．８ｇ／ｍｉｎで外径が２９５φのシリカ多孔質母材
が得られた。このとき使用した同芯円状多重管バーナー
の口径は得られたシリカ多孔質母材の０．２９倍であっ
た。Comparative Example 4 A concentric circular multi-tube burner having a diameter of 87 mm and a burner elevation angle of 45 ° was used, and the diameter of the silica porous matrix growth pseudosphere was 1.
It was fixedly installed so as to be 40 mm. At this time, the diameter of the silica porous base material pseudo sphere was 1.61 times the diameter of the burner. 510 N1 / min of hydrogen gas was added to this burner,
Oxygen gas 153 Nl / min, nitrogen gas 64 Nl / min
oxyhydrogen flame is formed by supplying min, and silicon tetrachloride, which is a glass raw material, is added to the center layer of the burner at 12.0 Nl / min.
(5.46 kg / hr) was supplied to synthesize the silica porous matrix, yield 55.5%, synthesis rate 1
A silica porous base material having an outer diameter of 295φ was obtained at 7.8 g / min. The diameter of the concentric circular multi-tube burner used at this time was 0.29 times that of the obtained silica porous base material.
【００２６】比較例５ 径が８７ｍｍの同芯円状多重管バーナーをバーナー仰角
を６０゜にしてシリカ多孔質母材成長疑似球の直径が１
６０ｍｍとなるように固定設置した。このときシリカ多
孔質母材疑似球の直径はバーナー口径の１．７７倍であ
った。このバーナーに水素ガスを５１０Ｎｌ／ｍｉｎ，
酸素ガスを１５３Ｎｌ／ｍｉｎ，窒素ガスを６４Ｎｌ／
ｍｉｎ供給して酸水素火炎を形成し、バーナーの中心層
にガラス原料である四塩化珪素を１２．０Ｎｌ／ｍｉｎ
（５．４６ｋｇ／ｈｒ）を供給してシリカ多孔質母材の
合成を行なったところ、シリカ多孔質母材の先端部が変
形したため合成を中止した。Comparative Example 5 A concentric circular multi-tube burner having a diameter of 87 mm and a burner elevation angle of 60 ° was used, and the diameter of the silica porous matrix growth pseudosphere was 1.
It fixedly installed so that it might become 60 mm. At this time, the diameter of the silica porous base material pseudo sphere was 1.77 times the burner diameter. This burner was supplied with hydrogen gas at 510 Nl / min,
Oxygen gas 153 Nl / min, nitrogen gas 64 Nl / min
oxyhydrogen flame is formed by supplying min, and silicon tetrachloride, which is a glass raw material, is added to the center layer of the burner at 12.0 Nl / min.
When (5.46 kg / hr) was supplied to synthesize the silica porous matrix, the synthesis was stopped because the tip of the silica porous matrix was deformed.
【００２７】比較例６ 径が５３ｍｍの同芯円状多重管バーナーをバーナー仰角
を４５゜にしてシリカ多孔質母材成長疑似球の直径が１
７０ｍｍとなるように固定設置した。このときシリカ多
孔質母材疑似球の直径はバーナー口径の３．２１倍であ
った。このバーナーに水素ガスを１１８Ｎｌ／ｍｉｎ，
酸素ガスを５５Ｎｌ／ｍｉｎ，窒素ガスを２７Ｎｌ／ｍ
ｉｎ供給して酸水素火炎を形成し、バーナーの中心層に
ガラス原料である四塩化珪素を４．０Ｎｌ／ｍｉｎ
（１．８２ｋｇ／ｈｒ）を供給してシリカ多孔質母材の
合成を行なったところ、１２０分後にシリカ多孔質母材
側面部に剥離が生じたため、合成を中止した。COMPARATIVE EXAMPLE 6 A concentric circular multi-tube burner having a diameter of 53 mm was used with the burner elevation angle set to 45 °, and the diameter of the silica porous matrix growth pseudo sphere was 1.
It was fixedly installed at 70 mm. At this time, the diameter of the silica porous base material pseudo sphere was 3.21 times the caliber of the burner. Hydrogen gas was added to this burner at 118 Nl / min,
Oxygen gas is 55 Nl / min, nitrogen gas is 27 Nl / m
Into supply oxyhydrogen flame, and silicon tetrachloride as a glass raw material is 4.0 Nl / min in the center layer of the burner.
When (1.82 kg / hr) was supplied to synthesize the porous silica preform, peeling occurred on the side surface of the porous silica preform after 120 minutes, so the synthesis was stopped.
【００２８】[0028]
【発明の効果】以上の説明から明らかなようにように、
本発明の製造方法によれば、シリカ多孔質母材の外径変
動や変形及び側面部にヒビ割れや剥離を発生させずにシ
リカ多孔質母材を高収率かつ高合成速度で製造すること
ができ、ＶＡＤ法による石英ガラスの製造におけるその
生産性と経済性を大きく向上させることができる効果を
有するものである。As is clear from the above description,
According to the production method of the present invention, it is possible to produce a silica porous base material at a high yield and a high synthesis rate without causing an outer diameter variation or deformation of the silica porous base material and cracking or peeling on the side surface. It is possible to improve the productivity and the economical efficiency in the production of quartz glass by the VAD method.
【図１】実施例１におけるシリカ多孔質母材と同芯円状
多重管バーナーの相対位置関係を示す図である。FIG. 1 is a diagram showing a relative positional relationship between a porous silica preform and a concentric circular multi-tube burner in Example 1.
【図２】比較例２におけるシリカ多孔質母材と同芯円状
多重管バーナーの相対位置関係を示す図である。FIG. 2 is a diagram showing a relative positional relationship between a silica porous base material and a concentric circular multi-tube burner in Comparative Example 2.
【図３】比較例３におけるシリカ多孔質母材と同芯円状
多重管バーナーの相対位置関係を示す図である。FIG. 3 is a diagram showing a relative positional relationship between a porous silica preform and a concentric circular multi-tube burner in Comparative Example 3.
１：シリカ多孔質母材 ２：同芯円状多重管バーナー ３：シリカ多孔質母材成長面疑似球 ４：シリカ多孔質母材成長面疑似球の中心 ａ：同芯円状多重管バーナーの口径 ｂ：シリカ多孔質母材の外径 ｃ：シリカ多孔質母材成長面疑似球の直径 1: Silica porous base material 2: Concentric circular multi-tube burner 3: Silica porous base material growth surface pseudo-sphere 4: Silica porous base material growth surface pseudo-sphere center a: Concentric circular multi-tube burner Caliber b: Outside diameter of silica porous base material c: Diameter of silica porous base material growth surface pseudosphere
───────────────────────────────────────────────────── フロントページの続き (72)発明者 植竹 孝 東京都武蔵野市吉祥寺南町一丁目27番１号 エヌ・ティ・ティ・アドバンステクノロ ジ株式会社内 (72)発明者 小田切 泰樹 山口県新南陽市宮の前２−６−10 (72)発明者 塩田 英司 山口県防府市大字大崎276−376 (72)発明者 久保 富義 山口県下松市大字末武中33番地の80 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Uetake 1-27-1 Kichijoji Minamimachi, Musashino City, Tokyo NTT Advanced Technology Co., Ltd. (72) Inventor Yasuki Odagiri Shinnanyo, Yamaguchi Prefecture 2-6-10 Miyanomae (72) Inventor Eiji Shioda 276-376 Osaki, Hofu City, Yamaguchi Prefecture 276-376 (72) Tomiyoshi Kubo, 80, 33, Suetsumu, Oita, Kudamatsu City, Yamaguchi Prefecture
Claims (1)
ガス及び支燃性ガスを同芯円状多重管バーナーに供給し
て、火炎加水分解させてシリカ微粒子を生成し、これを
出発部材上に堆積させ、該出発部材をシリカ微粒子の堆
積速度にあわせて上方に引上げるシリカ多孔質母材の製
造方法において、該同芯円状多重管バーナーの口径の
１．８〜３．０倍の直径を有するシリカ多孔質母材成長
面疑似球の法線と該同芯円状多重管バーナーの中心軸が
一致するように該同芯円状多重管バーナーを固定設置す
ることを特徴とするシリカ多孔質母材の製造方法。1. A gaseous glass raw material, a combustible gas, an inert gas, and a combustion-supporting gas are supplied to a concentric circular multi-tube burner to cause flame hydrolysis to produce silica fine particles, which are used as a starting member. In the method for producing a porous silica preform, which is deposited on the above, and the starting member is pulled upward in accordance with the deposition rate of the silica fine particles, the diameter of the concentric circular multi-tube burner is 1.8 to 3.0 times. Characterized in that the concentric circular multi-tube burner is fixedly installed so that the normal line of the silica porous base material growth surface pseudosphere having a diameter of and the central axis of the concentric circular multi-tube burner coincide with each other. Method for producing silica porous matrix.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12443592A JPH05319849A (en) | 1992-05-18 | 1992-05-18 | Production of silica porous preform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12443592A JPH05319849A (en) | 1992-05-18 | 1992-05-18 | Production of silica porous preform |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05319849A true JPH05319849A (en) | 1993-12-03 |
Family
ID=14885424
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12443592A Pending JPH05319849A (en) | 1992-05-18 | 1992-05-18 | Production of silica porous preform |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05319849A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10320531A1 (en) * | 2003-04-30 | 2004-11-25 | Schott Glas | Arrangement for producing quartz glass rollers comprises a burner which moves between two reversing points according to a path-time law on a spatial curve |
| WO2004108594A1 (en) * | 2003-06-11 | 2004-12-16 | Research Institute Of Industrial Science & Technology | A method for fabricating a porous silica sphere |
| JP2013006722A (en) * | 2011-06-23 | 2013-01-10 | Sumitomo Electric Ind Ltd | Method for producing base material for synthetic quartz glass and base material for synthetic quartz glass |
-
1992
- 1992-05-18 JP JP12443592A patent/JPH05319849A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10320531A1 (en) * | 2003-04-30 | 2004-11-25 | Schott Glas | Arrangement for producing quartz glass rollers comprises a burner which moves between two reversing points according to a path-time law on a spatial curve |
| DE10320531B4 (en) * | 2003-04-30 | 2007-07-05 | Schott Ag | Method for melting quartz glass rolls |
| DE10320531B8 (en) * | 2003-04-30 | 2007-10-18 | Schott Ag | Method for melting quartz glass rolls |
| WO2004108594A1 (en) * | 2003-06-11 | 2004-12-16 | Research Institute Of Industrial Science & Technology | A method for fabricating a porous silica sphere |
| JP2013006722A (en) * | 2011-06-23 | 2013-01-10 | Sumitomo Electric Ind Ltd | Method for producing base material for synthetic quartz glass and base material for synthetic quartz glass |
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