JPH01230444A - Production of preform for optical fiber - Google Patents
Production of preform for optical fiberInfo
- Publication number
- JPH01230444A JPH01230444A JP5376788A JP5376788A JPH01230444A JP H01230444 A JPH01230444 A JP H01230444A JP 5376788 A JP5376788 A JP 5376788A JP 5376788 A JP5376788 A JP 5376788A JP H01230444 A JPH01230444 A JP H01230444A
- Authority
- JP
- Japan
- Prior art keywords
- glass
- raw material
- flame
- gas
- fine particles
- 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
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 8
- 239000013307 optical fiber Substances 0.000 title claims description 8
- 239000011521 glass Substances 0.000 claims abstract description 36
- 239000002994 raw material Substances 0.000 claims abstract description 26
- 239000000463 material Substances 0.000 claims abstract description 15
- 238000000034 method Methods 0.000 claims abstract description 14
- 150000004703 alkoxides Chemical class 0.000 claims abstract description 11
- 239000010419 fine particle Substances 0.000 claims abstract description 8
- 238000000151 deposition Methods 0.000 claims abstract description 5
- 239000004215 Carbon black (E152) Substances 0.000 claims abstract description 4
- 229930195733 hydrocarbon Natural products 0.000 claims abstract description 4
- 239000007858 starting material Substances 0.000 claims abstract description 4
- 125000001183 hydrocarbyl group Chemical group 0.000 claims abstract description 3
- 230000003301 hydrolyzing effect Effects 0.000 claims abstract description 3
- 239000005373 porous glass Substances 0.000 claims description 6
- 150000001875 compounds Chemical class 0.000 claims description 3
- 239000007789 gas Substances 0.000 abstract description 9
- 239000000567 combustion gas Substances 0.000 abstract description 7
- 239000012535 impurity Substances 0.000 abstract description 7
- 238000006460 hydrolysis reaction Methods 0.000 abstract description 6
- 239000011261 inert gas Substances 0.000 abstract description 5
- 230000007062 hydrolysis Effects 0.000 abstract description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052799 carbon Inorganic materials 0.000 abstract description 2
- 229910000039 hydrogen halide Inorganic materials 0.000 abstract description 2
- 239000012433 hydrogen halide Substances 0.000 abstract description 2
- 238000002485 combustion reaction Methods 0.000 abstract 1
- 150000002430 hydrocarbons Chemical class 0.000 abstract 1
- 239000011148 porous material Substances 0.000 abstract 1
- 230000002265 prevention Effects 0.000 abstract 1
- 150000004820 halides Chemical class 0.000 description 9
- 230000000694 effects Effects 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- 239000004071 soot Substances 0.000 description 5
- 238000011109 contamination Methods 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 150000001805 chlorine compounds Chemical class 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- -1 hydrogen halides Chemical class 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 239000002912 waste gas Substances 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 208000005156 Dehydration Diseases 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 125000003545 alkoxy group Chemical group 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000010574 gas phase reaction Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 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]
- C03B37/01413—Reactant delivery systems
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/30—For glass precursor of non-standard type, e.g. solid SiH3F
- C03B2207/32—Non-halide
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (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)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野］
本発明は光ファイバ用母材の製造方法に関し、詳しくは
ガラス原料を火炎中で加水分解反応させることによシ生
成したガラス微粒子（スート）を堆積させて光ファイバ
用多孔質ガラス体を合成するいわゆるスート法による新
規な製法に関するものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a base material for optical fibers, and more specifically, glass fine particles (soot) produced by subjecting a glass raw material to a hydrolysis reaction in a flame. The present invention relates to a new manufacturing method using the so-called soot method, in which a porous glass body for optical fibers is synthesized by depositing.
従来のスート法においては、ガラス原料としてＳ ｉ
Ｃｔ、やＧθａｔ、％ Ｔ ｉ Ｃ４等のハロゲン化物
を用いることが一般的であシ、これをＨ！等の燃焼ガス
、Ｏ７等の助燃ガスさらにはＡｒ 等の不活性ガスと共
にバーナに導入し、火炎中で加水分解させてガラス微粒
子を合成していた。ハロゲン化物原料を用いる利点は、
原料精製が容易で、気相反応できるので反応系での汚染
防止が容易なため原料系からの不純物含盆を小さくでき
る点でおる。In the conventional soot method, Si
It is common to use halides such as Ct, Gθat, % Ti C4, and H! It was introduced into a burner together with combustion gases such as O7, auxiliary combustion gases such as O7, and inert gases such as Ar, and was hydrolyzed in a flame to synthesize glass particles. The advantages of using halide raw materials are
It is easy to purify the raw material, and since the gas phase reaction can be performed, it is easy to prevent contamination in the reaction system, so the amount of impurities contained in the raw material system can be reduced.
このようなハロゲン化物、例えば塩化物からガラス微粒
子８１０． ｆ合成する方法では、下記（１）式
％式％（１１
のようにＨＣｔが生成するだめ、反応系からこのＨＣｔ
を処理する必要があるに加え、装置の金属が侵食されや
すく設備保全がやっかいなこと、ガラス多孔質体へ装置
からの不純物が混入し易い等の難点がある。From such a halide, for example, a chloride, glass fine particles 810. In the f-synthesis method, HCt is not produced as shown in formula (1) below (11), but this HCt is removed from the reaction system.
In addition to the need to treat the metal, there are other drawbacks such as the metal of the device being easily corroded, making equipment maintenance a hassle, and impurities from the device easily entering the glass porous body.
本発明は上記の難点を解消した新規なスート法による光
ファイバ用母材の製造方法を提供すること全目的とし、
特にＨａｔのような侵食性が大きいガスの生成を見ない
ガラス原料を用いて、安全で設備コストが低く、しかも
不純物混入の危険もない方法を提案するものである。The entire purpose of the present invention is to provide a method for manufacturing an optical fiber base material using a novel soot method that eliminates the above-mentioned difficulties.
In particular, we propose a method that is safe, has low equipment costs, and has no risk of contamination with impurities, using a glass raw material that does not generate highly corrosive gases such as Hat.
〔課題を解決するだめの手段］
本発明は火炎中にガラス原料を導入して該ガラス原料を
火炎加水分解させることにより生成したガラス微粒子を
回転する出発材に堆積させて多孔質ガラス体を形成する
方法において、ガラス原料がアルコキシドを含有するこ
とを特徴５ｉ（ＯＯＨ，）、 （ただしＲは炭化水素
基）で表される化合物であることが特に好ましい実施態
様として挙げられる。[Means for Solving the Problems] The present invention involves introducing a glass raw material into a flame and flame hydrolyzing the glass raw material, thereby depositing glass fine particles on a rotating starting material to form a porous glass body. In a particularly preferred embodiment, the glass raw material contains an alkoxide and is a compound represented by (OOH,) (where R is a hydrocarbon group).
本発明はＶＡＤ法（気相軸付法）、外付は法その他の火
炎加水分解反応を利用してガラス微粒子を生成させる方
法において、ガラス原料がアルコキシド金倉むことを特
徴としている。特にｓｔ素のアルコキシドで５ｔ（ｏＲ
）、の一般式で表される化合物をガラス原料として用い
ることが原料調達の容易さ、気化性、母材への影響のな
い点で好ましい。上記一般式においてＲは−ＣＨＢ ｒ
−ＣｔＨｓ ＋ ” ” ” ＣｎＨ２ｎ＋１
等のアルキル基であるが、Ｒ＝ −ＣＨ，が最も沸点
が低く気化し易い、分子中においてＳｌ に対するＣ
（炭素原子）の割合が最も小さい点から特に好ましい。The present invention is a method of producing glass particles using a VAD method (vapor deposition method), an external deposition method, or other flame hydrolysis reactions, and is characterized in that the glass raw material is an alkoxide metal. In particular, 5t (oR
) It is preferable to use a compound represented by the general formula as the glass raw material in terms of ease of raw material procurement, vaporization, and no effect on the base material. In the above general formula, R is -CHBr
-CtHs + ” ” ” CnH2n+1
Among the alkyl groups, R= -CH, has the lowest boiling point and is easily vaporized.
(carbon atoms) is particularly preferred since it has the smallest ratio.
また金属Ｓｉ とＣｊＨ，ＯＲから簡単に合成するこ
とができる。Moreover, it can be easily synthesized from metal Si, CjH, and OR.
本発明ではガラス原料のすべてをアルコキシドとしても
よ５し、塩化物等のハロゲン化物とアルコキシドとを混
合して用いてもよい。また添加物については、Ｇｅｍ、
を添加する場合を例にとるとａｅ（ＯＲ）ｔを用い
てもよいし、Ｇｅ０４等のハロゲン化物或は両方を混じ
て用いることも可能である。In the present invention, all of the glass raw materials may be alkoxides, or a mixture of halides such as chlorides and alkoxides may be used. Regarding additives, Gem,
For example, ae(OR)t may be used, or a halide such as Ge04 or a mixture of both may be used.
本発明はガラス原料ＶＣアルコキ／ド？含逢ぜる意思外
は、従来公知の火炎加水分解法に準じて行なうことがで
きる。燃焼ガスとしては例えばＨ２、Ｃ！Ｈ，、Ｏ，Ｈ
，等の炭化水素ガス等を用いることができる。助燃ガス
としては例えばＯ７、さらに不活性ガスとして例えばＡ
ｒ、Ｈｅ等を用いることができる。５ｉ（ＯＲ）、又は
５ｉ（ＯＲ）、と８１ のハロゲン化物、これに要すれ
ば添カロ剤を加え、燃焼ガス、助燃ガス、不活性ガスを
ガラス微粒子合成用バーナーに導入し、バーナの火炎中
で加水分解反応によりガラス微粒子を生成させて、これ
を回転する出発材に堆積しガラス多孔質体（多孔質母材
）を得る。得られたガラス多孔質体を要すれば周知の脱
水処理例えばａｔ、ガス等の脱水ガス中で加熱する等の
処理により脱水し高温加熱により焼結して透明ガラス母
材を得ることができる。焼結工程において雰囲気ガス中
にＯ，ガス金倉ませることもできる。The present invention is based on glass raw material VC alkoxy/de? Except for the purpose of inclusion, it can be carried out according to the conventionally known flame hydrolysis method. Examples of combustion gas include H2, C! H,,O,H
, etc. can be used. As the auxiliary gas, for example, O7, and further as the inert gas, for example, A.
r, He, etc. can be used. 5i (OR), or 5i (OR), and 81 halide, if necessary, add a calorific agent, and introduce combustion gas, auxiliary combustion gas, and inert gas into a burner for glass particle synthesis, and the flame of the burner Glass particles are generated by a hydrolysis reaction in the chamber, and deposited on a rotating starting material to obtain a glass porous body (porous base material). If necessary, the obtained porous glass body can be dehydrated by a known dehydration treatment such as heating in a dehydrating gas such as AT or gas, and then sintered by high temperature heating to obtain a transparent glass base material. In the sintering process, O or gas can be added to the atmospheric gas.
なお、アルコキシド原料全バーナに導入するには微ｔの
場合は加熱蒸気とし、多量供給の際は噴霧によることが
できる。In order to introduce the alkoxide raw material into all burners, heated steam can be used when a small ton is required, and spraying can be used when a large amount is supplied.
本発明でガラス原料に含まれるアルコキシドは、火炎中
で下記（１１式のように反応する。In the present invention, the alkoxide contained in the glass raw material reacts in a flame as shown in the following equation (11).
５ｔ（ｏＲ）、 ＋ ２ ｎ、ｏ→ＳｉＯ，−１−４Ｒ
−ＯＨ・・・（１）生成するＲ−ＯＨは完全に燃焼して
反応系から除去されるし、もし母材中に炭素が残留して
も焼結時に雰囲気中に０２ を流すことによ５ ｃｏ
。5t (oR), + 2 n, o → SiO, -1-4R
-OH... (1) The generated R-OH is completely burned and removed from the reaction system, and even if carbon remains in the base material, it can be removed by flowing 02 into the atmosphere during sintering. 5 co
.
ＣＯ，として除去することができる。したがって本発明
の方法ではハロゲン化水素例えばＨＣｌの発生を見ない
か、非常に減少できるので、母材中への不純物混入や機
器の損傷がなくな９、廃ガス後処理を簡単にできる。さ
らに、本発明によれば従来法よりも収率（Ｓｉｎ、スー
ト重量／５ｌＯｔ ３！１算原料投入量×１００）が向
上できることが実験によシ確認された。It can be removed as CO. Therefore, in the method of the present invention, generation of hydrogen halides, such as HCl, is not generated or can be greatly reduced, so that there is no contamination of impurities into the base material or damage to equipment9, and waste gas post-treatment can be simplified. Furthermore, it has been confirmed through experiments that the present invention can improve the yield (Sin, soot weight/5 lOt 3!1 calculated raw material input amount x 100) compared to the conventional method.
実施例
ガラス原料としてＳ ｉ （ＯＣＲ，）、を用いて本発
明により多孔質ガラス母材を製造した。多重管バーナの
中心の第１ポートに５ｉ（０（１！Ｈ，）、をｉｓｚ／
分、第２ポートに燃焼ガスとしてＨ，１５ｔ／分、第３
ボートに不活性ガスとしてＡｒ５ｔ／分、第４ボートに
助燃ガスとして０．２５１／分を流し、通常の方法によ
シスート付したところ、ガラス微粒子の堆槓床度４１／
分で、母材外径１２ｆ）＋ｓｍφの多孔質ガラス母材が
製造できた。収率は６０％で、母材には割れ等なく良好
であった。なお５ｉｃ４’ｌ原料として同様条件の従来
法で多孔質母材を作製した場合の収率は約４０％である
。EXAMPLE A porous glass preform was manufactured according to the present invention using Si (OCR, ) as a glass raw material. 5i (0 (1!H,), isz/
min, H as combustion gas in the 2nd port, 15t/min, 3rd port
When 5 t/min of Ar was flowed into the boat as an inert gas and 0.251 t/min as an auxiliary gas was flowed into the fourth boat and syst was applied in the usual manner, the degree of sedimentation of glass particles was 41/min.
A porous glass preform with a preform outer diameter of 12 f)+smφ could be produced in minutes. The yield was 60%, and the base material was in good condition with no cracks or the like. Note that when a porous base material is produced using the conventional method under the same conditions as the 5ic4'l raw material, the yield is about 40%.
以上で得られた本発明母材を電気炉中で加熱して脱水・
透明化処理し透明プリフォームを得た。プリフォーム中
に気泡や結晶の生成はなかった。該ブリフォームラ線引
きして光ファイバとし、その特性を調べたところ、伝送
損失は１、５１１ｍで０．３ ｓ ａＢ／ｋｍ、 ｔ
ｓ ｓμｍで０２５ｄ Ｂ ／ｋｍと良好であった。The base material of the present invention obtained above is heated in an electric furnace to dehydrate and
A transparent preform was obtained by transparentization treatment. There were no bubbles or crystals formed in the preform. When we drew the briformula to make an optical fiber and investigated its characteristics, the transmission loss was 0.3 s aB/km at 1,511 m, t
It was good at 025dB/km in ssμm.
上記実施例ではガラス原料が５ｉ（ＯＣＲ５）、のみで
ある場合を挙げたが、これとＳ ｉ Ｏｔ、を併用した
り、Ｇ ｅ （０ＣＨ３）ｔ 又はＧｅ０４等を添加し
たシすることも同様の効果が得られる。又、５ｉ（ＯＣ
Ｒ，）。In the above example, the glass raw material is only 5i (OCR5), but it is also possible to use it in combination with SiOt, or add Ge(0CH3)t or Ge04 etc. Effects can be obtained. Also, 5i (OC
R,).
にかえて５１（ｏａ、ａ、）、等を用いることも本発明
の範囲に包含されるものである。It is also within the scope of the present invention to use 51 (oa, a,), etc. instead.
〔発明の効果］
以上説明のように、本発明は塩化物等のハロゲン化脛素
のみ（ｉｌ−原料とする火炎加水分解法によるガラス微
粒子合成の際のよりなＨｏｔ等のハロゲン化水素の発生
がないか低減できるので、機器の損傷とこれによる不純
物の母材中への混入を防止できるに加え、ハロゲン化水
素除去や廃ガス処理も不要でめ９、収率も向上するとい
う非常に有利な方法であり、光ファイバ用ガラス母材や
その他の高品質ガラスの製造分野に用いて多大の効果ヲ
萎する。[Effects of the Invention] As explained above, the present invention is effective in reducing the generation of hydrogen halides such as hot halides such as chlorides during the synthesis of glass fine particles by flame hydrolysis using only chlorides and other halides (IL) as raw materials. This has the great advantage of not only preventing damage to equipment and contamination of impurities into the base material, but also eliminating the need for hydrogen halide removal and waste gas treatment,9 and improving yields. This method has great effects when used in the field of manufacturing glass preforms for optical fibers and other high-quality glasses.
Claims (1)
炎加水分解させることにより生成したガラス微粒子を回
転する出発材に堆積させて多孔質ガラス体を形成する方
法において、ガラス原料がアルコキシドを含有すること
を特徴とする光ファイバ用母材の製造方法。（２）アル
コキシドが一般式Ｓｉ（ＯＲ）＿４（ただしＲは炭化水
素基）で表される化合物である特許請求の範囲第１項記
載の光ファイバ用母材の製造方法。(1) In a method in which a porous glass body is formed by depositing glass fine particles produced by introducing a glass raw material into a flame and flame hydrolyzing the glass raw material on a rotating starting material, the glass raw material contains alkoxides. 1. A method for producing an optical fiber base material, characterized in that: (2) The method for producing an optical fiber preform according to claim 1, wherein the alkoxide is a compound represented by the general formula Si(OR)_4 (where R is a hydrocarbon group).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5376788A JPH01230444A (en) | 1988-03-09 | 1988-03-09 | Production of preform for optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5376788A JPH01230444A (en) | 1988-03-09 | 1988-03-09 | Production of preform for optical fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01230444A true JPH01230444A (en) | 1989-09-13 |
Family
ID=12951960
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5376788A Pending JPH01230444A (en) | 1988-03-09 | 1988-03-09 | Production of preform for optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01230444A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0529189A2 (en) * | 1991-08-26 | 1993-03-03 | Corning Incorporated | Method of making fused silica |
-
1988
- 1988-03-09 JP JP5376788A patent/JPH01230444A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0529189A2 (en) * | 1991-08-26 | 1993-03-03 | Corning Incorporated | Method of making fused silica |
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