JPH05294658A - Production of quartz-based glass - Google Patents
Production of quartz-based glassInfo
- Publication number
- JPH05294658A JPH05294658A JP9437092A JP9437092A JPH05294658A JP H05294658 A JPH05294658 A JP H05294658A JP 9437092 A JP9437092 A JP 9437092A JP 9437092 A JP9437092 A JP 9437092A JP H05294658 A JPH05294658 A JP H05294658A
- Authority
- JP
- Japan
- Prior art keywords
- molded body
- porous glass
- molding
- glass
- silica
- 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
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C3/00—Glass compositions
- C03C3/04—Glass compositions containing silica
- C03C3/06—Glass compositions containing silica with more than 90% silica by weight, e.g. quartz
-
- 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
- C03B37/0128—Manufacture of preforms for drawing fibres or filaments starting from pulverulent glass
- C03B37/01282—Manufacture of preforms for drawing fibres or filaments starting from pulverulent glass by pressing or sintering, e.g. hot-pressing
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2201/00—Glass compositions
- C03C2201/02—Pure silica glass, e.g. pure fused quartz
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2203/00—Production processes
- C03C2203/50—After-treatment
- C03C2203/52—Heat-treatment
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Glass Melting And Manufacturing (AREA)
Abstract
Description
【0001】[発明の目的][Object of the Invention]
【0002】[0002]
【産業上の利用分野】この発明は、光学用あるいは光通
信用に用いる石英系ガラスの製造方法に関し、特に成形
助剤を用いて成形された多孔質ガラス成形体からの石英
系ガラス製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing silica-based glass used for optical or optical communication, and more particularly to a method for producing silica-based glass from a porous glass compact molded using a molding aid. ..
【0003】[0003]
【従来の技術】石英系ガラスの製造方法として、シリカ
粉末を成形し、得られた多孔質ガラス成形体を透明ガラ
ス化する方法が公知である。この際に、成形性を向上さ
せるためにシリカ粉末に成形助剤を添加して多孔質ガラ
ス成形体を成形することが一般的に行われている。2. Description of the Related Art As a method for producing quartz glass, a method is known in which silica powder is molded and the obtained porous glass molded body is made into transparent glass. At this time, in order to improve the moldability, it is generally performed to add a molding aid to silica powder to mold a porous glass molded body.
【0004】この場合、多孔質ガラス成形体に含有され
る成形助剤は除去しなければならず、このような成形助
剤の除去(以下、脱脂と称する)は、従来、酸素又は不
活性ガスなどの雰囲気で行われている。そして、特に高
純度の製品の製造においては、脱脂の後、塩素雰囲気等
で精製を行っている。In this case, the molding aid contained in the porous glass molded body must be removed, and such molding aid removal (hereinafter referred to as degreasing) has conventionally been carried out using oxygen or an inert gas. It is performed in an atmosphere such as. Then, particularly in the production of high-purity products, purification is performed in a chlorine atmosphere or the like after degreasing.
【0005】[0005]
【発明が解決しようとする課題】成形助剤を含む多孔質
ガラス成形体の脱脂工程を、酸素又は不活性ガス雰囲気
中で行っても、成形助剤及びシリカ粉末に含まれている
アルカリ及びアルカリ土類金属、遷移金属等を除去する
ことはほとんどできず、これらの不純物が残存すると以
下に示すような悪影響をもたらす。Even if the step of degreasing a porous glass molding containing a molding aid is carried out in an oxygen or inert gas atmosphere, the alkali and alkali contained in the molding aid and silica powder It is almost impossible to remove the earth metal, transition metal, etc., and if these impurities remain, the following adverse effects are brought about.
【0006】すなわち、アルカリ及びアルカリ土類金属
は成形体のガラス化過程において結晶化を引き起こし、
遷移金属はその金属自身が光の吸収ピークを有するため
に光の透過率を劣化させてしまう。そのため、高純度で
あることが必要とされる光導波路及び光学部品に使用す
る石英ガラスの製造には、脱脂工程の後に精製を行うの
である。That is, alkali and alkaline earth metals cause crystallization in the vitrification process of the molded body,
Since the transition metal itself has a light absorption peak, the light transmittance is deteriorated. Therefore, in the production of silica glass used for optical waveguides and optical components that require high purity, purification is performed after the degreasing step.
【0007】ところで、多孔質ガラス体の精製には、少
なくとも800℃以上の温度で塩素ガスの存在下で加熱
処理を行うことが広く知られている。しかしながら、成
形助剤を含有した多孔質ガラス成形体においては、多孔
質ガラス体を構成するシリカ粒子の表面にも主に成形助
剤に含まれる多量の不純物が付着しているため、直接8
00℃を超える温度で精製した場合には表面の不純物が
粒子内部に侵入してしまい、多孔質成形体を精製するこ
とが非常に困難となってしまう。By the way, it is widely known that in refining the porous glass body, heat treatment is performed at a temperature of at least 800 ° C. or higher in the presence of chlorine gas. However, in the porous glass molded body containing the molding aid, a large amount of impurities mainly contained in the molding aid adheres to the surface of the silica particles constituting the porous glass body.
When the refining is performed at a temperature higher than 00 ° C., impurities on the surface penetrate into the inside of the particles, which makes it very difficult to purify the porous molded body.
【0008】一方、多孔質ガラス成形体を塩化チオニー
ル+酸素の雰囲気中400℃で精製し、さらに1000
℃にて再度精製する方法が知られている(Grastech Ber
60巻 4号 125 〜132 ペ−ジ 1987年)。しかし
ながら、この方法を採用しても、成形助剤を含んだ多孔
質ガラス成形体から透明なガラスを得ることは非常に困
難である。On the other hand, the porous glass molded body was refined at 400 ° C. in an atmosphere of thionyl chloride + oxygen, and further 1000
A method of refining again at ℃ is known (Grastech Ber
Volume 60, No. 4, 125-132, 1987). However, even if this method is adopted, it is very difficult to obtain transparent glass from a porous glass molded body containing a molding aid.
【0009】この発明はかかる事情に鑑みてなされたも
のであって、成形助剤を用いて成形された多孔質ガラス
成形体から高純度石英系ガラスを得ることができる石英
系ガラスの製造方法を提供することを目的とする。The present invention has been made in view of the above circumstances, and provides a method for producing a silica-based glass capable of obtaining a high-purity silica-based glass from a porous glass molding formed by using a molding aid. The purpose is to provide.
【0010】[0010]
【課題を解決するための手段】この発明は、上記課題を
解決するために、成形助剤を含んだ多孔質ガラス成形体
に対し、塩素及び酸素を含有する雰囲気中で400〜8
00℃の範囲の温度で加熱処理を施し、さらに塩素を含
有する雰囲気中で800℃以上の温度で加熱処理を施す
ことを特徴とする石英系ガラスの製造方法を提供する。In order to solve the above-mentioned problems, the present invention provides a porous glass molded body containing a molding aid in a range of 400 to 8 in an atmosphere containing chlorine and oxygen.
Provided is a method for producing a silica-based glass, which comprises performing a heat treatment at a temperature in the range of 00 ° C. and further performing a heat treatment at a temperature of 800 ° C. or higher in an atmosphere containing chlorine.
【0011】この発明では、まず第1工程として、多孔
質ガラス成形体に対し塩素及び酸素を含有する雰囲気中
で400〜800℃の範囲の温度で加熱処理を施すが、
その理由は以下のとおりである。In the present invention, as the first step, the porous glass molded body is heat-treated at a temperature in the range of 400 to 800 ° C. in an atmosphere containing chlorine and oxygen.
The reason is as follows.
【0012】すなわち、前述したように成形助剤を含ん
だ多孔質ガラス成形体を直接800℃を超える温度で加
熱処理を行った場合、塩素の混入の有無にかかわらず粒
子表面に付着した不純物が粒子内部に侵入し、しかも成
形体の気孔が一部閉じしまい、その後の精製が効果的に
行われず、また400℃未満では脱脂が不十分となって
しまうからである。なお、ここで雰囲気中に含有される
塩素源としては塩素ガスに限らず、塩化チオニールのよ
うに装置内で反応させることにより塩素ガスが発生する
ものを用いることも可能である。That is, as described above, when the porous glass molded body containing the molding aid is directly subjected to the heat treatment at a temperature higher than 800 ° C., impurities adhering to the particle surface are irrespective of whether chlorine is mixed or not. This is because it penetrates into the inside of the particles, and some of the pores of the molded body are closed, the subsequent purification is not effectively performed, and degreasing becomes insufficient at less than 400 ° C. Here, the chlorine source contained in the atmosphere is not limited to chlorine gas, and it is also possible to use, for example, thionyl chloride, which generates chlorine gas by reacting in the apparatus.
【0013】次に、第2工程として、400〜800℃
の範囲の温度で加熱処理された多孔質ガラス体に対し、
塩素を含有する雰囲気中で800℃以上の温度で加熱処
理を施す。この工程は従来の精製工程に対応するもので
ある。Next, in the second step, 400 to 800 ° C.
For the porous glass body heat-treated at a temperature in the range of,
Heat treatment is performed at a temperature of 800 ° C. or higher in an atmosphere containing chlorine. This process corresponds to the conventional purification process.
【0014】この発明でいう多孔質ガラス成形体は、純
シリカ粉末、あるいは純シリカ粉末にリン、アルミニウ
ム、ボロン等のドーパントを添加した粉末など、いわゆ
る石英系ガラス粉末を用いて、鋳込み、押出し、加圧成
形等のセラミックスの分野で一般的に用いられる成形方
法を用いて成形されたものである。The porous glass molded article referred to in the present invention is cast and extruded using so-called silica glass powder such as pure silica powder, or powder obtained by adding dopants such as phosphorus, aluminum and boron to pure silica powder. It is molded using a molding method generally used in the field of ceramics such as pressure molding.
【0015】また成形助剤は、成形性が困難である石英
系粉末に成形性を付与する作用、あるいは成形体の強度
を向上させる作用を有する添加物であり、粉末凝集体を
1次粒子に分解する作用、成形型からの離型性を向上さ
せる作用、又は粉末の表面の改質作用、界面張力を低下
させる作用を有する物も含まれる。Further, the molding aid is an additive having a function of imparting moldability to the quartz-based powder, which is difficult to mold, or a function of improving the strength of the molded body, and the powder agglomerates are converted into primary particles. Also included are those having a function of decomposing, a function of improving releasability from a molding die, a function of modifying the surface of powder, and a function of lowering interfacial tension.
【0016】成形助剤の具体例としては、ポリビニルア
ルコール、ポリビニルブチラール、ポリエチレングリコ
ール、メチルセルロース、カルボキシメチルセルロー
ス、エチルセルロース、グリセリン等、また、アクリル
酸オリゴマー、ステアリン酸、エチレングリコール、テ
トラメチレングリコール等の有機物、さらにテトラエト
キシシラン等の金属アルコキシドなどがある。しかし、
これらに限られるものではなく他の物質を用いることも
できる。また、これらの添加量及び配合比についても特
定範囲に限定されるものではなく、成形方法により適宜
設定される。Specific examples of the molding aid include polyvinyl alcohol, polyvinyl butyral, polyethylene glycol, methyl cellulose, carboxymethyl cellulose, ethyl cellulose, glycerin, etc., and organic substances such as acrylic acid oligomer, stearic acid, ethylene glycol, tetramethylene glycol, etc. Further, there are metal alkoxides such as tetraethoxysilane. But,
The material is not limited to these, and other substances can be used. Further, the addition amount and the compounding ratio of these are not limited to a specific range, and may be appropriately set depending on the molding method.
【0017】[0017]
【作用】この発明においては、先ず、酸素及び塩素ガス
を含有する雰囲気中で400〜800℃の範囲の温度で
加熱処理を行うことにより、多孔質ガラス成形体の成形
助剤を除去すると同時に、多孔質ガラス成形体を構成す
る成形助剤及び石英系ガラス粉末に含まれる不純物、特
にアルカリ及びアルカリ土類金属、遷移金属等の除去が
可能となる。この場合に、特に成形体の石英系ガラス粉
末粒子に付着しているこれら不純物を除去することが可
能となる。さらに、これら不純物は塩素を用いること
で、石英系ガラス粉末粒子表面に付着することなく除去
することが可能であるばかりでなく、多孔質ガラス成形
体表面に装置等から発生する不純物が付着することを防
止することも可能となる。次いで、通常一般に行われて
いる800℃以上の塩素含有雰囲気中での加熱処理を行
うことにより、より一層精製効果を向上させることが可
能となる。In the present invention, first, heat treatment is carried out in an atmosphere containing oxygen and chlorine gas at a temperature in the range of 400 to 800 ° C. to remove the molding aid of the porous glass molded body and at the same time, It becomes possible to remove impurities, particularly alkali and alkaline earth metals, transition metals and the like contained in the molding aid and the quartz glass powder that form the porous glass molded body. In this case, it becomes possible to remove these impurities adhering to the silica glass powder particles of the molded body. Further, by using chlorine, these impurities can be removed without adhering to the surface of the silica-based glass powder particles, and the impurities generated from the device etc. adhere to the surface of the porous glass molded body. It is also possible to prevent Then, heat treatment in a chlorine-containing atmosphere at 800 ° C. or higher, which is generally performed, is performed to further improve the refining effect.
【0018】[0018]
【実施例】以下、この発明の実施例について図面を参照
して具体的に説明する。ここでは、例として石英系ガラ
スとして高純度の光ファイバの製造方法について説明す
る。Embodiments of the present invention will be described below in detail with reference to the drawings. Here, as an example, a method of manufacturing a high-purity optical fiber made of silica glass will be described.
【0019】図1は、石英系ガラス粉末から多孔質成形
体を製造するための加圧成形装置を示す概略図である。
この装置は、高圧印加装置11内に被成形物を充填した
成形ゴム型13とその外側に取り付けられた支持筒17
とがセットされ、高圧印加装置11により成形ゴム型の
周囲に充填された滑油のような圧力媒体15を介して成
形ゴム型13内の被成形物に圧力を与えてそれを加圧成
形するものである。なお、参照符号19は成形ゴム型1
3の下蓋、12は上蓋であり、14は圧力媒体出入口で
ある。FIG. 1 is a schematic view showing a pressure molding apparatus for manufacturing a porous molded body from quartz glass powder.
This apparatus includes a molding rubber mold 13 in which a high pressure applying device 11 is filled with a molding target and a support cylinder 17 attached to the outside thereof.
Are set, and the high pressure applying device 11 applies pressure to the object to be molded in the molding rubber mold 13 through the pressure medium 15 such as lubricating oil filled around the molding rubber mold to press-mold it. It is a thing. Reference numeral 19 is a molded rubber mold 1.
3 is a lower lid, 12 is an upper lid, and 14 is a pressure medium inlet / outlet port.
【0020】この装置を用いて以下のように多孔質ガラ
ス成形体を成形した。先ず、成形ゴム型13内に、その
中心にコアとその周囲のクラッドの一部とを有するガラ
スロッド18を設置した。Using this apparatus, a porous glass molded body was molded as follows. First, a glass rod 18 having a core in the center thereof and a part of a clad around the core was placed in the molded rubber mold 13.
【0021】ここで成形ゴム型13としてはニトリルゴ
ム製で、内径が50mmφ、長さ約270mmのものを用い
た。なお、成形ゴム型13としては、シリコンゴム製の
ものを使用することもできる。また、ガラスロッド18
としては気相法の一つであるVAD法で作製したもので
あって、クラッド/コアが約3で、外径7.5mmφ、長
さ約260mm、比屈折率が約0.35%のものを用い
た。The molding rubber mold 13 used here was made of nitrile rubber and had an inner diameter of 50 mmφ and a length of about 270 mm. The molding rubber mold 13 may be made of silicon rubber. Also, the glass rod 18
Is manufactured by the VAD method, which is one of the vapor phase methods, and has a clad / core of about 3, an outer diameter of 7.5 mmφ, a length of about 260 mm, and a relative refractive index of about 0.35%. Was used.
【0022】多孔質ガラス成形体を成形するための粉末
としては、平均粒径が約8μmの市販のシリカ粉末を用
いた。この粉末に成形助剤としてのポリビニルアルコー
ル(以下、PVAと記す)と純水とを加え、濃度約60
%のスラリーとした。このスラリーを噴霧乾燥機を用
い、乾燥・造粒した。この際の造粒粒子の平均粒径は約
150μmであった。また粒子中の成形助剤PVAの濃
度は2重量%であった。As the powder for forming the porous glass molded body, a commercially available silica powder having an average particle size of about 8 μm was used. Polyvinyl alcohol (hereinafter referred to as PVA) as a molding aid and pure water were added to this powder to give a concentration of about 60.
% Slurry. This slurry was dried and granulated using a spray dryer. The average particle size of the granulated particles at this time was about 150 μm. The concentration of the molding aid PVA in the particles was 2% by weight.
【0023】このようにして得られたシリカ粉末16を
成形ゴム型に充填した。この際に粉末16を均一に充填
するために下蓋19に図示しない振動機で振動を与えな
がら充填した。充填密度は約0.9g/cm3 であった。
充填後上蓋12を閉め、成形ゴム型の外側に支持筒17
を取り付けた。この支持筒17は圧力を印加した際、圧
力が径方向にのみ印加されるようにするためである。The silica powder 16 thus obtained was filled in a molding rubber mold. At this time, in order to uniformly fill the powder 16, the lower lid 19 was filled while vibrating with a vibrator (not shown). The packing density was about 0.9 g / cm 3 .
After filling, the upper lid 12 is closed, and the support cylinder 17 is placed outside the molding rubber mold.
Attached. This is because the support cylinder 17 is adapted to apply the pressure only in the radial direction when the pressure is applied.
【0024】その後、支持筒17が取り付けられた成形
ゴム型13を高圧印加装置11にセットした。この場合
に、圧力媒体出入口14から圧力媒体15が侵入し、成
形ゴム型13に圧力が印加される。成形条件は1.5to
n /cm2 の圧力を1分間印加し、その後約20分間かけ
てゆっくりと減圧した。減圧終了後、高圧印加装置11
から、支持筒17が取り付けられた成形ゴム型13を取
り出し、上蓋12を開いて多孔質ガラス成形体を取り出
した。図2に示すように、多孔質ガラス成形体21がガ
ラスロッド18の周囲に形成された。多孔質ガラス成形
体には亀裂、割れはもちろん生じておらず、当然のこと
ながら、中心のガラスロッド18も割れは生じなかっ
た。得られた多孔質ガラス成形体の外径は約40mmφで
あった。After that, the molded rubber mold 13 to which the support cylinder 17 was attached was set in the high-voltage applying device 11. In this case, the pressure medium 15 enters from the pressure medium inlet / outlet 14 and pressure is applied to the molding rubber mold 13. Molding condition is 1.5 to
A pressure of n / cm 2 was applied for 1 minute, and then the pressure was slowly reduced over about 20 minutes. After decompression, the high voltage application device 11
From the above, the molded rubber mold 13 to which the support cylinder 17 was attached was taken out, the upper lid 12 was opened, and the porous glass molded body was taken out. As shown in FIG. 2, the porous glass molded body 21 was formed around the glass rod 18. Of course, neither cracks nor cracks were generated in the porous glass molded body, and naturally, the glass rod 18 at the center was not cracked. The outer diameter of the obtained porous glass molded body was about 40 mmφ.
【0025】次に、得られた多孔質ガラス成形体の成形
助剤、及び多孔質ガラス体粒子に含まれる不純物、特に
粉末の表面に付着しているアルカリ金属、アルカリ土類
金属及び遷移金属を取り除くため、加熱処理(脱脂工
程)を行った。この加熱処理は、図3に示すように、加
熱炉31の炉心管32内にガラスロッド18とその周囲
に形成された多孔質ガラス成形体21を挿入し、炉心管
32を酸素及び窒素の混合ガス中に塩素ガスを酸素の流
量の約10%の流量で供給した雰囲気中で行った。な
お、酸素と窒素との流量比は1:4とした。加熱条件
は、室温から600℃まで2℃/分の速度で昇温し、6
00℃で5時間保持した。Next, a molding aid for the obtained porous glass molded body and impurities contained in the porous glass body particles, particularly alkali metal, alkaline earth metal and transition metal adhering to the surface of the powder are added. In order to remove it, heat treatment (degreasing step) was performed. In this heat treatment, as shown in FIG. 3, the glass rod 18 and the porous glass molded body 21 formed around the glass rod 18 are inserted into the furnace core tube 32 of the heating furnace 31, and the furnace core tube 32 is mixed with oxygen and nitrogen. It was performed in an atmosphere in which chlorine gas was supplied into the gas at a flow rate of about 10% of the flow rate of oxygen. The flow rate ratio of oxygen and nitrogen was set to 1: 4. The heating condition is that the temperature is raised from room temperature to 600 ° C. at a rate of 2 ° C./min.
It was kept at 00 ° C for 5 hours.
【0026】この加熱処理が終了した後の多孔質ガラス
体について別の炉を用いて精製・ガラス化を行った。こ
の精製工程は、He,Cl2 雰囲気中1200℃の温度
で行った。次いで温度を1600℃に上昇させてHe雰
囲気中で透明ガラス化を行った。The porous glass body after this heat treatment was purified and vitrified using another furnace. This purification process was performed at a temperature of 1200 ° C. in a He, Cl 2 atmosphere. Next, the temperature was raised to 1600 ° C. and transparent vitrification was performed in a He atmosphere.
【0027】これら一連の工程により得られた光ファイ
バプリフォームには、気泡及び亀裂は認められなかっ
た。No bubbles and cracks were observed in the optical fiber preform obtained by these series of steps.
【0028】この光ファイバプリフォームを通常の方法
で線引きし、光ファイバを製造した。得られた光ファイ
バの伝送損失は0.36dB/kmであり、気相法で作
製したものと同等の特性を有していた。This optical fiber preform was drawn by a usual method to manufacture an optical fiber. The transmission loss of the obtained optical fiber was 0.36 dB / km, which was equivalent to that produced by the vapor phase method.
【0029】上記実施例では多孔質ガラス成形体を加圧
成形法により形成した場合について示したが、これに限
らず、鋳込み成形法及び押出し成形法で成形した場合で
あっても同様な加熱処理により同等な特性を有する光フ
ァイバが得られた。また光ファイバに限らず、光導波路
用基板あるいは石英ガラス棒、パイプ等についても高純
度のものを製造することができた。In the above examples, the case where the porous glass molded body was formed by the pressure molding method was shown, but the present invention is not limited to this, and the same heat treatment is applied even when it is molded by the casting molding method and the extrusion molding method. An optical fiber having equivalent characteristics was obtained. Further, not only the optical fiber but also the optical waveguide substrate, the quartz glass rod, the pipe and the like can be manufactured with high purity.
【0030】比較のため、加熱処理(脱脂)の際に塩素
ガスを用いなかった以外上記実施例と同じ条件で光ファ
イバを作製した。その結果得られた光ファイバの伝送損
失は0.42dB/kmと実施例の場合よりも損失が大
きくなった。この際の光ファイバにプリフォームに含ま
れている不純物を実施例と比較した結果を以下に示す。For comparison, an optical fiber was produced under the same conditions as in the above-mentioned example except that chlorine gas was not used during the heat treatment (degreasing). As a result, the transmission loss of the optical fiber obtained was 0.42 dB / km, which was larger than that of the example. The results of comparing the impurities contained in the preform in the optical fiber at this time with those of the example are shown below.
【0031】 実施例 比較例 Na <0.001 0.02 Ca <0.001 0.01 Fe <0.005 0.01 (単位:重量ppm) この結果から、塩素を用いて多孔質ガラス成形体を加熱
処理(脱脂)することによって、粒子に付着した不純
物、及び装置等からの汚染によって発生する不純物が多
孔質ガラス成形体表面に付着することが防止され、その
結果次工程で行う精製効果が向上したことが明白となっ
た。Example Comparative Example Na <0.001 0.02 Ca <0.001 0.01 Fe <0.005 0.01 (unit: ppm by weight) From these results, porous glass moldings were prepared using chlorine. By heat-treating (degreasing) the impurities adhered to the particles and the impurities generated by contamination from the device etc. are prevented from adhering to the surface of the porous glass molded body, and as a result, the purification effect performed in the next step It became clear that it improved.
【0032】次に、これも比較のため、加熱処理(脱
脂)における温度を400℃とした以外は実施例と同様
の条件で光ファイバプリフォームを作製した。その結
果、プリフォーム内に多数の気泡が認められ、光ファイ
バとすることができなかった。Next, for comparison, an optical fiber preform was produced under the same conditions as in the example except that the temperature in the heat treatment (degreasing) was 400 ° C. As a result, many bubbles were recognized in the preform, and it could not be used as an optical fiber.
【0033】[0033]
【発明の効果】この発明によれば、成形助剤を用いて成
形された多孔質ガラス成形体から高純度石英系ガラスを
得ることができる石英系ガラスの製造方法が提供され
る。Industrial Applicability According to the present invention, there is provided a method for producing a silica-based glass capable of obtaining a high-purity silica-based glass from a porous glass molded body that is molded using a molding aid.
【図1】石英系ガラス粉末からこの発明に用いられる多
孔質成形体を製造するための加圧成形装置を示す概略
図。FIG. 1 is a schematic view showing a pressure molding device for manufacturing a porous molded body used in the present invention from a silica glass powder.
【図2】ガラスロッドの周囲に多孔質ガラス成形体が形
成された状態を示す図。FIG. 2 is a view showing a state in which a porous glass molded body is formed around a glass rod.
【図3】この発明を実施するために用いられる多孔質ガ
ラス成形体を加熱処理するための炉を示す模式図。FIG. 3 is a schematic diagram showing a furnace for heat-treating a porous glass molded body used for carrying out the present invention.
11…高圧印加装置、12…上蓋、13…成形ゴム型、
14…圧力媒体出入口、15…圧力媒体、16…シリカ
粉末、17…支持筒、18…コアロッド、19…下蓋、
21…多孔質ガラス成形体、31…加熱炉、32…炉心
管。11 ... High-voltage applying device, 12 ... Upper lid, 13 ... Molded rubber mold,
14 ... Pressure medium inlet / outlet, 15 ... Pressure medium, 16 ... Silica powder, 17 ... Support cylinder, 18 ... Core rod, 19 ... Lower lid,
21 ... Porous glass molding, 31 ... Heating furnace, 32 ... Furnace core tube.
フロントページの続き (72)発明者 吉田 和昭 東京都千代田区丸の内2丁目6番1号 古 河電気工業株式会社内Front page continuation (72) Inventor Kazuaki Yoshida 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd.
Claims (1)
対し、塩素及び酸素を含有する雰囲気中で400〜80
0℃の範囲の温度で加熱処理を施し、さらに塩素を含有
する雰囲気中で800℃以上の温度で加熱処理を施すこ
とを特徴とする石英系ガラスの製造方法。1. A porous glass molded body containing a molding aid is added in an atmosphere containing chlorine and oxygen in an amount of 400 to 80.
A method for producing a silica-based glass, which comprises performing a heat treatment at a temperature in the range of 0 ° C. and further performing a heat treatment at a temperature of 800 ° C. or higher in an atmosphere containing chlorine.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9437092A JPH05294658A (en) | 1992-04-14 | 1992-04-14 | Production of quartz-based glass |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9437092A JPH05294658A (en) | 1992-04-14 | 1992-04-14 | Production of quartz-based glass |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH05294658A true JPH05294658A (en) | 1993-11-09 |
Family
ID=14108433
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP9437092A Pending JPH05294658A (en) | 1992-04-14 | 1992-04-14 | Production of quartz-based glass |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH05294658A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100472862B1 (en) * | 1999-08-03 | 2005-03-07 | 데구사 아게 | Sintered materials and a process for the production thereof |
US8578736B2 (en) | 2008-09-23 | 2013-11-12 | Corning Incorporated | Soot radial pressing for optical fiber overcladding |
JP2016175794A (en) * | 2015-03-19 | 2016-10-06 | 古河電気工業株式会社 | Method for manufacturing optical fiber preform |
US10494291B2 (en) | 2014-10-23 | 2019-12-03 | Corning Incorporated | Hygroscopic additives for silica soot compacts and methods for forming optical quality glass |
US10793466B2 (en) | 2015-02-27 | 2020-10-06 | Corning Incorporated | Nanoparticle additives for silica soot compacts and methods for strengthening silica soot compacts |
-
1992
- 1992-04-14 JP JP9437092A patent/JPH05294658A/en active Pending
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100472862B1 (en) * | 1999-08-03 | 2005-03-07 | 데구사 아게 | Sintered materials and a process for the production thereof |
US8578736B2 (en) | 2008-09-23 | 2013-11-12 | Corning Incorporated | Soot radial pressing for optical fiber overcladding |
US10494291B2 (en) | 2014-10-23 | 2019-12-03 | Corning Incorporated | Hygroscopic additives for silica soot compacts and methods for forming optical quality glass |
US10793466B2 (en) | 2015-02-27 | 2020-10-06 | Corning Incorporated | Nanoparticle additives for silica soot compacts and methods for strengthening silica soot compacts |
JP2016175794A (en) * | 2015-03-19 | 2016-10-06 | 古河電気工業株式会社 | Method for manufacturing optical fiber preform |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JPH051223B2 (en) | ||
US4680046A (en) | Method of preparing preforms for optical fibers | |
US4938788A (en) | Method of producing uniform silica glass block | |
JP3387562B2 (en) | Production of vitreous silica products | |
US5185020A (en) | Method for manufacturing a silica-base material for optical fiber | |
JP2000044225A (en) | Method for forming article using sol-gel method | |
JPH0826742A (en) | Synthetic quartz glass powder | |
KR890001123B1 (en) | Method for crystalization of glass preform | |
JP2925797B2 (en) | Purification method of porous preform for optical fiber | |
JPH05294658A (en) | Production of quartz-based glass | |
JP2808857B2 (en) | Heating furnace and manufacturing method of glass preform for optical fiber | |
JPWO2002102725A1 (en) | Manufacturing method of glass base material and glass base material | |
JPS5842136B2 (en) | Manufacturing method of optical fiber base material | |
JPH0776092B2 (en) | Glass manufacturing method | |
JPS63176325A (en) | Production of glass preform for optical fiber | |
JPH0479981B2 (en) | ||
JPS6081038A (en) | Manufacture of optical glass fiber containing tio2 | |
JPH0419173B2 (en) | ||
JP2004338992A (en) | Method for manufacturing glass preform | |
JPH06127949A (en) | Production of quartz glass | |
JPH0764574B2 (en) | Method for manufacturing rod-shaped quartz glass preform | |
JPS63151639A (en) | Production of glass preformer for optical fiber | |
JP2620275B2 (en) | Glass manufacturing method | |
JPS632900B2 (en) | ||
JPH0570157A (en) | Production of quartz-based glass matrix |