JPH0247414B2 - HIKARIFUAIBABOZAINOSEIZOHOHO - Google Patents
HIKARIFUAIBABOZAINOSEIZOHOHOInfo
- Publication number
- JPH0247414B2 JPH0247414B2 JP13772384A JP13772384A JPH0247414B2 JP H0247414 B2 JPH0247414 B2 JP H0247414B2 JP 13772384 A JP13772384 A JP 13772384A JP 13772384 A JP13772384 A JP 13772384A JP H0247414 B2 JPH0247414 B2 JP H0247414B2
- Authority
- JP
- Japan
- Prior art keywords
- glass
- plasma torch
- chamber
- gas
- supplied
- 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 - Lifetime
Links
- 239000011521 glass Substances 0.000 claims description 28
- 239000007789 gas Substances 0.000 claims description 17
- 238000000034 method Methods 0.000 claims description 17
- 238000006243 chemical reaction Methods 0.000 claims description 7
- NBVXSUQYWXRMNV-UHFFFAOYSA-N fluoromethane Chemical compound FC NBVXSUQYWXRMNV-UHFFFAOYSA-N 0.000 claims description 6
- 239000012495 reaction gas Substances 0.000 claims description 6
- 229910052731 fluorine Inorganic materials 0.000 claims description 5
- 239000011737 fluorine Substances 0.000 claims description 5
- 239000002994 raw material Substances 0.000 claims description 5
- 230000015572 biosynthetic process Effects 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 claims description 2
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 claims 1
- 230000002194 synthesizing effect Effects 0.000 claims 1
- 239000000463 material Substances 0.000 description 9
- 229910003902 SiCl 4 Inorganic materials 0.000 description 8
- 239000013307 optical fiber Substances 0.000 description 8
- 238000004519 manufacturing process Methods 0.000 description 7
- 229910004298 SiO 2 Inorganic materials 0.000 description 5
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 4
- PXBRQCKWGAHEHS-UHFFFAOYSA-N dichlorodifluoromethane Chemical compound FC(F)(Cl)Cl PXBRQCKWGAHEHS-UHFFFAOYSA-N 0.000 description 3
- 235000019404 dichlorodifluoromethane Nutrition 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 2
- KYKAJFCTULSVSH-UHFFFAOYSA-N chloro(fluoro)methane Chemical compound F[C]Cl KYKAJFCTULSVSH-UHFFFAOYSA-N 0.000 description 2
- 239000002019 doping agent Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 238000007740 vapor deposition Methods 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 238000007496 glass forming Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
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]
- C03B37/018—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] by glass deposition on a glass substrate, e.g. by inside-, modified-, plasma-, or plasma modified- chemical vapour deposition [ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod
- C03B37/01807—Reactant delivery systems, e.g. reactant deposition burners
- C03B37/01815—Reactant deposition burners or deposition heating means
- C03B37/01823—Plasma deposition burners or heating means
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/08—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant
- C03B2201/12—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant doped with fluorine
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Plasma & Fusion (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Glass Compositions (AREA)
Description
【発明の詳細な説明】
［発明の背景と目的］
本発明は、プラズマ炎を用いた光フアイバ母材
の製造方法の改良に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Background and Objects of the Invention] The present invention relates to an improvement in a method for manufacturing an optical fiber preform using a plasma flame.
一般に、光フアイバ母材の製造は、MCVD（化
学気相沈積）法、VAD（気相軸付）法によつて行
われており、そして、これらの方法の熱源は主に
酸水素バーナが用いられている。 Generally, optical fiber base materials are manufactured using the MCVD (chemical vapor deposition) method and the VAD (vapor deposition) method, and the heat source for these methods is mainly an oxyhydrogen burner. It is being
一方、プラズマ炎を用いる場合は、プラズマ炎
の高温を利用して直接ガラス成形が可能であり、
プラズマ炎の中心は約２万℃である。この温度を
利用し合成ガラスを形成する方法としては、(1)プ
ラズマ炎のジエツト部に混合ガスを導入する方法
及び(2)プラズマガスに混合ガスを混合する方法な
どがある。このうち、(1)はふつ素ドープガスを形
成するには、ドーパント材であるフロンガスの熱
分解反応が十分でなく、ふつ素の高ドープ化が難
しい。また、(2)は混合ガスの増加によりプラズマ
炎が不安定となり、ガラス膜の成長速度を向上す
ることが難しい。 On the other hand, when using plasma flame, it is possible to directly form glass by utilizing the high temperature of plasma flame.
The temperature at the center of the plasma flame is approximately 20,000°C. Methods for forming synthetic glass using this temperature include (1) a method of introducing a mixed gas into the jet portion of a plasma flame, and (2) a method of mixing a mixed gas with plasma gas. Among these, (1) is difficult to highly dope with fluorine because the thermal decomposition reaction of the dopant material, fluorocarbon gas, is insufficient to form a fluorine-doped gas. In addition, in (2), the plasma flame becomes unstable due to an increase in the mixed gas, making it difficult to improve the growth rate of the glass film.
本発明は上記の状況に鑑みなされたものであ
り、ふつ素の高ドープ化が得られると共に、ガラ
ス膜の成長速度を向上できる光フアイバ母材の製
造方法を提供することを目的としたものである。 The present invention was made in view of the above situation, and aims to provide a method for manufacturing an optical fiber base material that can achieve high fluorine doping and improve the growth rate of the glass film. be.
［発明の概要］
本発明の光フアイバ母材の製造方法は、高周波
プラズマトーチによりプラズマ炎を発生させ該プ
ラズマ炎にガラス形成用の原料を反応ガス導入管
を介し供給し、加熱反応によりチヤンバ内のガラ
ス旋盤に支持されたターゲツト棒外周面に直接ふ
つ素ドープガラスの混合を行なう場合に、上記高
周波プラズマトーチの後方からフロン系ガスを供
給し、かつ、前方からガラス形成用の主原料を上
記チヤンバ内に供給する方法である。即ち、フロ
ン系の反応ガス高周波プラズマトーチの後方から
供給しプラズマ炎の熱によりＦを分離させ、この
Ｆを高周波プラズマトーチの前方に供給される
SiCl4から形成されるSiC2とチヤンバ内で反応さ
せ、ターゲツト棒外周上にＦドープガラスを形成
する方法がある。[Summary of the Invention] The method for manufacturing an optical fiber base material of the present invention involves generating a plasma flame using a high-frequency plasma torch, supplying a raw material for glass formation to the plasma flame through a reaction gas introduction tube, and causing a heating reaction inside the chamber. When mixing fluorine-doped glass directly onto the outer peripheral surface of a target rod supported on a glass lathe, a fluorocarbon-based gas is supplied from the rear of the high-frequency plasma torch, and the main raw material for glass formation is mixed from the front. This is a method of supplying it into the chamber. That is, a fluorocarbon-based reactive gas is supplied from the rear of the high-frequency plasma torch, F is separated by the heat of the plasma flame, and this F is supplied to the front of the high-frequency plasma torch.
There is a method in which F-doped glass is formed on the outer periphery of a target rod by reacting it with SiC 2 formed from SiCl 4 in a chamber.
［実施例］
以下本発明の光フアイバ母材の製造方法を実施
例を用い図面により説明する。図は実施装置の断
面図である。図において、１は高周波プラズマト
ーチ、２は高周波プラズマトーチ１の上方から吹
き込まれるフロン12（CCl2F2）の反応ガス導入
管、２Ａは高周波プラズマトーチ１の下方からチ
ヤンバ４内にガラス形成用の主原料のSiCl4を供
給する反応ガス導入管である。３はN2のガスが
供給されるガスシールキヤツプ、４はチヤンバで
ある。５はガラス旋盤で、ターゲツト棒６の回転
駆動及びヘツドを上下移動駆動するモータ１８を
それぞれ有する移動ヘツド１７によりターゲツト
棒６の両端を支承しており、ヘツド９上を軸方向
に駆動装置（図示せず）により駆動されるように
なつている。８はヘツド９上に取り付けられたス
トツパー、７はガラス膜、１０はバツフアタン
ク、１１は排気管、１２は熱交換器、１３はスク
ラバー、１４は排気フアン、１５はバルブ、１６
はガス圧力計である。[Example] Hereinafter, the method for manufacturing an optical fiber base material of the present invention will be explained using examples and drawings. The figure is a sectional view of the implementation device. In the figure, 1 is a high-frequency plasma torch, 2 is a reactant gas introduction pipe of Freon 12 (CCl 2 F 2 ) blown from above the high-frequency plasma torch 1, and 2A is a glass-forming tube from below the high-frequency plasma torch 1 into the chamber 4. This is a reaction gas introduction pipe that supplies SiCl 4 , the main raw material. 3 is a gas seal cap to which N 2 gas is supplied, and 4 is a chamber. Reference numeral 5 designates a glass lathe, in which both ends of the target rod 6 are supported by a movable head 17 having a motor 18 for rotating the target rod 6 and driving the head up and down, and a driving device (see Fig. (not shown). 8 is a stopper attached to the head 9, 7 is a glass membrane, 10 is a buffer tank, 11 is an exhaust pipe, 12 is a heat exchanger, 13 is a scrubber, 14 is an exhaust fan, 15 is a valve, 16
is a gas pressure gauge.
そして、ガラス膜７の精製にあたつては、高周
波プラズマトーチ１に、矢印の如く酸素を送り込
んで酸素プラズマ炎を発生させる。また、反応ガ
ス導入管２からフロンガス12を50c.c.／minを、反
応ガス導入管２ＡからSiCl42000mg／min酸素ガ
スキヤリアにして送り込み、反応チヤンバ４内の
プラズマ炎の下方で反応させ、10mmφの石英ガラ
ス棒のターゲツト棒７上に、ＦドープSiO2系ガ
ラス膜７を粋咳させる。ターゲツト棒６はガラス
旋盤５によつて一定の回転数にて回転駆動される
ようになつており、ガラス旋盤５はヘツド９上を
矢印の軸方向に駆動されてターゲツト棒６の外周
及び長手方向にガラス膜７を形成することができ
る。尚、フロンガスは、CCl2F2・CF4・CClF3・
CCl3F・C2F6・C2ClF5・C2Cl4F2・SIF4を用いて
もよい。 To purify the glass film 7, oxygen is fed into the high frequency plasma torch 1 as shown by the arrow to generate an oxygen plasma flame. In addition, 50 c.c./min of chlorofluorocarbon gas 12 is fed from the reaction gas introduction pipe 2, and SiCl 4 2000 mg/min oxygen gas carrier is fed from the reaction gas introduction pipe 2A, and the reaction is caused to occur below the plasma flame in the reaction chamber 4. An F-doped SiO 2 -based glass film 7 is sputtered onto a target rod 7 made of quartz glass rod. The target rod 6 is rotated at a constant rotation speed by a glass lathe 5, and the glass lathe 5 is driven on a head 9 in the axial direction of the arrow to rotate the target rod 6 in the outer circumference and longitudinal direction. A glass film 7 can be formed thereon. In addition, fluorocarbon gases include CCl 2 F 2 , CF 4 , CClF 3 ,
CCl 3 F.C 2 F 6.C 2 ClF 5.C 2 Cl 4 F 2.SIF 4 may also be used.
ここで、Ｆドープガラス形成にドーパント材と
してフロン12（CCl2F2）を用いた。Ｃ−Ｆの結合
エネルギーは、105Kcal／molであり、Ｆを遊離
させるためには高温を必要とし、この場合、プラ
ズマガスと同じ上部からフロン12を供給すること
により、プラズマトーチの高温により完全に分離
される。 Here, Freon 12 (CCl 2 F 2 ) was used as a dopant material to form the F-doped glass. The bond energy of C-F is 105 Kcal/mol, and high temperature is required to liberate F. In this case, by supplying Freon 12 from the same top as the plasma gas, it can be completely removed by the high temperature of the plasma torch. Separated.
プラズマ炎の下法にはSiOl4が供給される。
SiCl4は(1)式で示す反応を行なう。 SiOl 4 is supplied in the plasma flame method.
SiCl 4 performs the reaction shown in equation (1).
SiCl4＋O2→SiO2＋2Cl2 ……(1)
(1)式は、1000℃以上で完全に右に反応は移る。
SiO2は分解したＦと反応し、Ｆドープガラスが
形成される。(1)式よりSiO2は、SiCl4の量に依存
し、ここでは2000mg／minの場合成形速度は
25μm／cycleであつた。尚、移動ベツト１７の移
動速度30mm／minである。また、5000mg／minの
SiCl4を供給してもガラス膜７の形成が可能であ
ることも確認済みである。 SiCl 4 +O 2 →SiO 2 +2Cl 2 ...(1) In equation (1), the reaction completely shifts to the right at 1000°C or higher.
SiO 2 reacts with decomposed F to form F-doped glass. From equation (1), SiO 2 depends on the amount of SiCl 4 , and here, at 2000 mg/min, the molding speed is
It was 25μm/cycle. Note that the moving speed of the moving bed 17 is 30 mm/min. Also, 5000mg/min
It has also been confirmed that the glass film 7 can be formed even if SiCl 4 is supplied.
このように本実施例の光フアイバ母材の製造方
法においては、フロン系の反応ガスを高周波プラ
ズマトーチの後法から供給しプラズマ炎の熱によ
りＦを確実に分離させ、このＦを高周波プラズマ
トーチの前方に供給されるSiCl4から形成される
SiO2反応材料とチヤンバ内で反応させターゲツ
ト棒外周上にＦドープガラスを形成することがで
きるので、ふつ素を高ドープ化でき高い成長速度
でターゲツト棒外周上にガラス膜を形成できて生
産性を向上できる。 In this way, in the method for manufacturing the optical fiber base material of this embodiment, a fluorocarbon-based reactive gas is supplied from the high-frequency plasma torch after the high-frequency plasma torch, F is reliably separated by the heat of the plasma flame, and this F is transferred to the high-frequency plasma torch. formed from SiCl 4 fed in front of
Since F-doped glass can be formed on the outer periphery of the target rod by reacting with the SiO 2 reaction material in the chamber, it is possible to highly dope fluorine and form a glass film on the outer periphery of the target rod at a high growth rate, increasing productivity. can be improved.
上記実施例はターゲツト棒の軸線が水平の場合
について述べたが垂直位置の場合でも作用効果は
同じである。 Although the above embodiment has been described with respect to the case where the axis of the target rod is horizontal, the operation and effect are the same even when the axis of the target rod is in a vertical position.
［発明の効果］
以上記述した如く本発明の光フアイバ母材の製
造方法によれば、ふつ素の高ドープ化が得られる
と共にガラス膜の成長速度を向上できる効果を有
するものである。[Effects of the Invention] As described above, according to the method for manufacturing an optical fiber base material of the present invention, it is possible to achieve high doping of fluorine and to improve the growth rate of a glass film.
図は本発明の光フアイバ母材の製造方法を実施
例する装置の断面図である。
１……高周波プラズマトーチ、２，２Ａ……反
応ガス導入管、４……チヤンバ、５……ガラス旋
盤、６……ターゲツト棒、７……ガラス膜。
The figure is a sectional view of an apparatus for carrying out the method of manufacturing an optical fiber preform according to the present invention. DESCRIPTION OF SYMBOLS 1... High frequency plasma torch, 2, 2A... Reaction gas introduction tube, 4... Chamber, 5... Glass lathe, 6... Target rod, 7... Glass film.
Claims (1)
生させ該プラズマ炎にガラス形成用の原料を反応
ガス導入管を介し供給し、加熱反応によりチヤン
バ内のガラス旋盤に支持されたターゲツト棒外周
面に直接ふつ素ドープガラスの合成を行なう方法
において、上記高周波プラズマトーチの後方から
フロン系ガスを供給し、かつ、前方からガラス形
成用の主原料を上記チヤンバ内に供給することを
特徴とする光フアイバ母材の製造方法。1. Generate a plasma flame with a high-frequency plasma torch, supply raw materials for glass formation to the plasma flame through a reaction gas introduction tube, and directly dope fluorine onto the outer circumferential surface of a target rod supported on a glass lathe in a chamber by a heating reaction. A method for synthesizing glass, characterized in that a fluorocarbon gas is supplied from the rear of the high-frequency plasma torch, and a main raw material for glass formation is supplied from the front into the chamber. Method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13772384A JPH0247414B2 (en) | 1984-07-03 | 1984-07-03 | HIKARIFUAIBABOZAINOSEIZOHOHO |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13772384A JPH0247414B2 (en) | 1984-07-03 | 1984-07-03 | HIKARIFUAIBABOZAINOSEIZOHOHO |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6117433A JPS6117433A (en) | 1986-01-25 |
| JPH0247414B2 true JPH0247414B2 (en) | 1990-10-19 |
Family
ID=15205319
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13772384A Expired - Lifetime JPH0247414B2 (en) | 1984-07-03 | 1984-07-03 | HIKARIFUAIBABOZAINOSEIZOHOHO |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0247414B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0581517U (en) * | 1992-04-03 | 1993-11-05 | ポップリベット・ファスナー株式会社 | clip |
| JP2009007242A (en) * | 2007-05-29 | 2009-01-15 | Shin Etsu Chem Co Ltd | Method of manufacturing optical fiber preform using high frequency induction thermal plasma torch |
| US8322165B2 (en) | 2007-08-10 | 2012-12-04 | Shin-Etsu Chemical Co., Ltd. | Apparatus for fabricating an optical fiber |
| US8707741B2 (en) | 2009-07-27 | 2014-04-29 | Shin-Etsu Chemical Co., Ltd | Method of manufacturing optical fiber preform using plasma torch |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102005015706B4 (en) * | 2005-04-05 | 2008-07-03 | Heraeus Quarzglas Gmbh & Co. Kg | Process for producing a preform for optical fibers |
| JP4926164B2 (en) * | 2008-12-26 | 2012-05-09 | 信越化学工業株式会社 | Optical fiber preform manufacturing method and apparatus using high frequency induction thermal plasma torch |
-
1984
- 1984-07-03 JP JP13772384A patent/JPH0247414B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0581517U (en) * | 1992-04-03 | 1993-11-05 | ポップリベット・ファスナー株式会社 | clip |
| JP2009007242A (en) * | 2007-05-29 | 2009-01-15 | Shin Etsu Chem Co Ltd | Method of manufacturing optical fiber preform using high frequency induction thermal plasma torch |
| US8322165B2 (en) | 2007-08-10 | 2012-12-04 | Shin-Etsu Chemical Co., Ltd. | Apparatus for fabricating an optical fiber |
| US8707741B2 (en) | 2009-07-27 | 2014-04-29 | Shin-Etsu Chemical Co., Ltd | Method of manufacturing optical fiber preform using plasma torch |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6117433A (en) | 1986-01-25 |
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