JPH0524854A - Production of glass article - Google Patents
Production of glass articleInfo
- Publication number
- JPH0524854A JPH0524854A JP3179814A JP17981491A JPH0524854A JP H0524854 A JPH0524854 A JP H0524854A JP 3179814 A JP3179814 A JP 3179814A JP 17981491 A JP17981491 A JP 17981491A JP H0524854 A JPH0524854 A JP H0524854A
- Authority
- JP
- Japan
- Prior art keywords
- glass
- temperature
- heat treatment
- heat
- glass article
- 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.)
- Granted
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]
- C03B37/01446—Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Thermal 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)
- Glass Melting And Manufacturing (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は高品質のガラス物品の製
造方法に関するものであり、特に光ファイバ用プリフォ
ームあるいはその中間製品の製造に最適な製法を提供す
るものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a high-quality glass article, and particularly to a method for producing an optical fiber preform or an intermediate product thereof.
【０００２】[0002]
【従来の技術】気相合成法、例えば気相軸付法（ＶＡＤ
法）あるいは外付法（ＯＶＤ法）より合成されたガラス
微粒子堆積体は、電気炉にて高温加熱処理することによ
り透明ガラス化され、ガラス物品となる。従来、透明ガ
ラス化は常圧にて雰囲気をＨｅあるいはハロゲンガス
（特に塩素）を微量に含んだ不活性ガスとし、狭い加熱
帯をトラバースし、通過させることにより透明化する方
法がとられてきた（ゾーン加熱方式）。あるいは、ガラ
ス微粒子堆積体全長が均熱となるように、広い加熱域を
持つ電気炉にガラス微粒子堆積体を挿入し、炉温を徐々
に昇温することにより透明化する方法が採用されている
（均熱加熱方式）。2. Description of the Related Art A vapor phase synthesis method, for example, a method with a vapor phase axis (VAD
Method) or an externally added method (OVD method), the fine glass particle deposit is subjected to high-temperature heat treatment in an electric furnace to be vitrified into a glass article. Heretofore, transparent vitrification has been carried out by using He or an inert gas containing a small amount of halogen gas (especially chlorine) as an atmosphere at atmospheric pressure, and traversing a narrow heating zone to make it transparent. (Zone heating method). Alternatively, a method is adopted in which the glass particle deposit is inserted into an electric furnace having a wide heating area so that the entire length of the glass particle deposit becomes uniform, and the temperature of the furnace is gradually raised to make it transparent. (Soaking and heating method).
【０００３】これらの方法では、透明化する際、ガラス
微粒子堆積体の粒子間に閉じ込められたガスあるいは透
明化時に溶け込んだガスにより、ガラス物品内に空孔
（気泡と呼ぶ）が残留（または後の高温加工時に発生す
る場合もある）してしまう問題があり、近年、特開昭６
３−２０１０２５号公報に記載されるような真空雰囲気
あるいは減圧雰囲気にて透明化する方法が提案されてい
る。この方法では、雰囲気が真空あるいは減圧下のた
め、ガラス微粒子堆積体中のガスが脱気され、ガラス中
にはガスが残留しないことが期待される。[0003] In these methods, pores (referred to as bubbles) remain (or later) in the glass article due to the gas trapped between the particles of the glass particulate deposit or the gas dissolved during the clearing during the transparentization. However, in recent years, there is a problem in that
There is proposed a method of making transparent in a vacuum atmosphere or a reduced pressure atmosphere as described in JP-A-3-201025. In this method, since the atmosphere is under vacuum or under reduced pressure, the gas in the glass particulate deposit is degassed, and it is expected that the gas will not remain in the glass.
【０００４】[0004]
【発明が解決しようとする課題】従来、真空あるいは減
圧雰囲気で加熱処理する装置は、図２に示すような構成
となっている。すなわち、ガラス微粒子堆積体１１の周
囲を囲む炉芯管１２、この外側に加熱用ヒータ１３が設
置された均熱炉が、ヒートシールド１４を挟んで真空容
器１５の中に入った構成となっている。真空容器１５内
には、脱気用配管１６に接続された真空ポンプ１７によ
り減圧、真空雰囲気となる構造となっており、この状態
でヒータ温度を上げることにより、炉芯管１２内に挿入
されているガラス微粒子堆積体１１が透明化される。Conventionally, an apparatus for heat treatment in a vacuum or reduced pressure atmosphere has a structure as shown in FIG. That is, the furnace core tube 12 surrounding the glass particulate deposit body 11 and the soaking furnace in which the heater 13 for heating is installed outside the furnace core tube 12 are arranged inside the vacuum container 15 with the heat shield 14 interposed therebetween. There is. The vacuum container 15 has a structure in which a vacuum pump 17 connected to a degassing pipe 16 reduces the pressure and creates a vacuum atmosphere. In this state, the heater temperature is raised to insert the furnace core tube 12. The glass particulate deposit 11 that is present is made transparent.
【０００５】上記、加熱炉を用い減圧，真空雰囲気で、
従来法による加熱処理の一例として図６に示す温度条件
にて透明化温度（通常１５５０℃〜１６５０℃）まで温
度を上げ透明化したところ、期待に反し、気泡が残留す
る場合が散見された。また、透明化したガラス物品の外
径が長手方向に均一とならず、図３に示す如く両端で太
く中間部で細くなるような形状となってしまった。この
方法で得られた加熱ロッドを用いて高品質なガラス物品
を製造するためには、気泡の残留を安定して減少あるい
はなくすことが必要であり、且つ仕上がった透明ガラス
物品を均一外径とすることが必要である。[0005] Using the heating furnace, under reduced pressure and vacuum atmosphere,
As an example of the heat treatment according to the conventional method, when the temperature was raised to the clearing temperature (usually 1550 ° C. to 1650 ° C.) under the temperature conditions shown in FIG. 6 to make the material transparent, unexpectedly, there were some cases where bubbles remained. Further, the outer diameter of the transparent glass article was not uniform in the longitudinal direction, and as shown in FIG. 3, the glass article had a shape in which both ends were thick and the middle part was thin. In order to produce a high-quality glass article using the heating rod obtained by this method, it is necessary to stably reduce or eliminate residual air bubbles, and the finished transparent glass article has a uniform outer diameter. It is necessary to.
【０００６】[0006]
【課題を解決するための手段】上記問題を解決する手段
として、本発明は気相合成法によりガラス微粒子堆積体
を合成し、該ガラス微粒子堆積体を真空あるいは減圧雰
囲気で加熱処理することにより透明ガラス化してガラス
物品を製造する方法において、加熱処理としてガラス微
粒子堆積体が収縮をしない温度での第１の熱処理、第１
の熱処理より高く且つ透明ガラス化しない温度での第２
の熱処理、透明ガラス化する温度での第３の熱処理の少
なくとも３段階の熱処理を行うことを特徴とするもので
ある。本発明において、第１の熱処理温度は１０００〜
１１５０℃、第２の熱処理温度は１２５０〜１５００
℃、第３の熱処理温度は１５５０℃〜１６５０℃として
行うことが特に好ましい。As means for solving the above-mentioned problems, the present invention is transparent by synthesizing glass particulate deposits by a gas phase synthesis method and heating the glass particulate deposits in a vacuum or reduced pressure atmosphere. In the method for producing a glass article by vitrification, the first heat treatment at a temperature at which the glass particle deposit does not shrink as the heat treatment,
Second at a temperature higher than the heat treatment of
And at least three stages of the third heat treatment at the temperature of vitrification. In the present invention, the first heat treatment temperature is 1000 to
1150 ° C., second heat treatment temperature is 1250 to 1500
C. and the third heat treatment temperature are particularly preferably 1550.degree. C. to 1650.degree.
【０００７】[0007]
【作用】図１に、本発明の熱処理の温度パターンの概略
図を示す。図２に示す如く、真空あるいは減圧下にセッ
トされたガラス微粒子堆積体１１を、まず１１００〜１
１５０℃の温度でキープされた雰囲気に３０分から２時
間放置する。次に炉温を上昇し１２５０℃〜１４５０℃
の間の温度でやはり３０分から２時間放置し、その後透
明化温度まで温度を上げ、透明化する。透明化温度は通
常１５５０〜１６５０℃の範囲が用いられる。本発明に
おいてガラス微粒子堆積体の加熱処理は真空又は減圧雰
囲気で行い、他のガスの流入はない。炉内金属の酸化を
防ぐ目的からパージガスとしてはＨe、Ｎ2 、Ａr など
の不活性ガスが用いられる。炉内圧力は昇温前には５〜
１０Ｐａが望ましい。熱処理中は１００Ｐａ以下好まし
くは２０Ｐａ以下で行なう。高温になると圧力が上がる
が、これも殆ど１００Ｐａとなる。FIG. 1 shows a schematic view of the temperature pattern of the heat treatment of the present invention. As shown in FIG. 2, the glass fine particle deposits 11 set under vacuum or reduced pressure are first set to 1100-1.
Leave in a maintained atmosphere at a temperature of 150 ° C. for 30 minutes to 2 hours. Next, the furnace temperature is raised to 1250 ° C to 1450 ° C.
It is left to stand for 30 minutes to 2 hours at a temperature between the above, and then the temperature is raised to the clearing temperature to make it transparent. The clearing temperature is usually in the range of 1550 to 1650 ° C. In the present invention, the heat treatment of the glass particulate deposit is performed in a vacuum or a reduced pressure atmosphere, and no other gas is introduced. An inert gas such as He, N 2 or Ar is used as a purge gas for the purpose of preventing the metal in the furnace from being oxidized. Before the temperature rise, the furnace pressure is 5
10 Pa is desirable. The heat treatment is performed at 100 Pa or less, preferably 20 Pa or less. The pressure rises at high temperature, but it is almost 100 Pa.
【０００８】一般に気相合成法で合成したガラス微粒子
堆積体は、０．１〜０．５μｍの微細な粒子が充填され
た構造となっているが、気相合成の条件により充填の様
子が異なり、微粒子の詰まり方が変わる。すなわち、カ
サ密度（空孔を含んだ単位堆積当りの重量：g/cm3 ）が
変化するわけである。合成時の粒子が小さく且つ温度が
高いほど空孔が少なく、カサ密度の大きな硬い堆積体が
得られることとなる。本発明のガラス微粒子堆積体とし
ては、密度０．１〜０．９g/cm3 程度のものを用いるこ
とが好ましい。密度がこの範囲未満又は範囲を越える
と、柔らかすぎるため割れやすく、或いは硬すぎて、す
でに取り込まれているガスをだっきすることが難しく、
気泡が残留しやすくなる。Generally, the glass fine particle deposits synthesized by the vapor phase synthesis method have a structure in which fine particles of 0.1 to 0.5 μm are filled, but the filling state differs depending on the conditions of the vapor phase synthesis. , The way the particles are clogged will change. That is, the bulk density (weight per unit deposit including pores: g / cm 3 ) changes. The smaller the particles during synthesis and the higher the temperature, the smaller the number of vacancies and the harder the deposit with a higher bulk density can be obtained. As the glass particle deposit of the present invention, it is preferable to use one having a density of about 0.1 to 0.9 g / cm 3 . If the density is below this range or exceeds this range, it is too soft and easily cracks, or too hard, and it is difficult to remove the gas that has already been taken in,
Air bubbles tend to remain.
【０００９】図５に示すようなＶＡＤ法では、バーナ５
１により形成される火炎５２内に温度分布が生ずるた
め、生成されるガラス微粒子堆積体５３内には半径方向
にもカサ密度の分布ができる。特に太径の堆積体の場合
には、カサ密度の大きな差ができることがある。カサ密
度が大きくなると微粒子で囲まれた空孔は小さくなり、
ガスの通り路が狭くなる。このため、真空あるいは減圧
下においても、ガスが抜けにくくなる限界が生ずること
になる。ガラス微粒子堆積体は周囲温度が上がるに従っ
て溶融合体し、空孔が次第に小さくなって最後に空孔が
なくなり透明化するが、この透明化は外周部から進行す
るため、温度が上がった後ではいくら真空下においても
ガスは抜けず、気泡が残留することになる。In the VAD method as shown in FIG. 5, the burner 5
Since a temperature distribution is generated in the flame 52 formed by No. 1, a bulk density distribution can be formed in the radial direction in the generated glass particle deposit body 53. Especially in the case of a large-diameter deposit, a large difference in bulk density may occur. As the bulk density increases, the pores surrounded by particles become smaller,
The gas passage becomes narrow. Therefore, there is a limit that the gas is difficult to escape even under vacuum or reduced pressure. The glass particle deposit melts and coalesces as the ambient temperature rises, and the pores gradually become smaller, and finally the pores disappear and become transparent. The gas does not escape even under vacuum, and bubbles remain.
【００１０】ガラス微粒子堆積体は上述したように、次
第に収縮していくが、収縮の仕方は温度の上がり方に依
存している。ところが、ガラス微粒子堆積体は均一に温
度が上昇していくわけではなく、例えば半径方向では表
面に比べ中心部の温度の上がり方が遅くなる。また、長
手方向では加熱表面積が大きい端部（上端、下端）で温
度が上がりやすくなる。従って上端、下端では比較的内
部にまで熱が伝わりやすく、収縮が進行しやすい。逆に
長手方向の中間部では端部に比べて収縮しにくい。収縮
は径方向に収縮するだけでなく、長手方向にも生ずるた
め、端部は長手方向に比較的大きく収縮し、透明化した
後のガラス物品の外径は太径になる。逆に、中間部では
長手方向の収縮が小さく、外径は細めとなりやすい。こ
うして外径変動が生ずると考えられるため、第１の熱処
理としては急速に透明化の進行しない温度にて保持する
ことにより、全体にわたって温度差を小さくし、徐々に
収縮させることが必要となる。そこで、ガラスの収縮が
起きない程度の高温、すなわち１１５０℃以下の温度で
加熱する本発明の第１の熱処理が必要となる。高温にし
ておくと、ガラス微粒子に吸着しているガスも抜けやす
くなるため有利であるため、８００℃以上であることが
望ましい。このときの減圧又は雰囲気は２０Ｐａ以下望
ましくは５〜１０Ｐａとする。As described above, the glass particulate deposit gradually shrinks, but the shrinking method depends on how the temperature rises. However, the temperature of the glass particle deposit does not rise uniformly, and the temperature rise in the central portion becomes slower in the radial direction than in the surface, for example. Further, in the longitudinal direction, the temperature tends to rise at the ends (upper end and lower end) having a large heating surface area. Therefore, at the upper end and the lower end, heat is relatively easily transferred to the inside, and contraction is likely to proceed. On the contrary, the intermediate portion in the longitudinal direction is less likely to contract than the end portion. Since the contraction not only contracts in the radial direction but also in the longitudinal direction, the end part relatively contracts in the longitudinal direction, and the outer diameter of the glass article after being transparent becomes large. On the contrary, in the middle portion, the contraction in the longitudinal direction is small, and the outer diameter is likely to be thin. Since it is considered that the outer diameter fluctuates in this way, it is necessary for the first heat treatment to reduce the temperature difference over the whole by gradually maintaining the temperature at a temperature at which the clearing does not proceed rapidly. Therefore, the first heat treatment of the present invention in which the glass is heated at a high temperature at which shrinkage does not occur, that is, at a temperature of 1150 ° C. or lower is required. It is advantageous to set the temperature to a high temperature because the gas adsorbed on the glass fine particles can easily escape, so that the temperature is preferably 800 ° C. or higher. The pressure reduction or atmosphere at this time is 20 Pa or less, and preferably 5 to 10 Pa.
【００１１】第２の熱処理として１２５０℃〜１５００
℃で保持すると、ガラス微粒子堆積体全体が徐々に収縮
するため、不均一が発生しにくく、均一な外径を持った
ガラス物品を得ることができる。この熱処理は１段のみ
でなく、例えば１３００℃で６０分間保持し、次に１４
００で６０分間保持するといった２段処理などを行え
ば、更に効果的である。このときの減圧又は真空雰囲気
としては、１００Ｐａ以下好ましくは２０Ｐａ以下で行
なう。以上の第１，２段の熱処理の後に、透明ガラス化
温度で熱処理することにより均一なガラス物品を得るこ
とができる。１００Ｐａ以下好ましくは２０Ｐａ以下で
行なう。As the second heat treatment, 1250 ° C. to 1500 ° C.
When kept at 0 ° C., the entire glass particle deposit gradually shrinks, so that nonuniformity hardly occurs and a glass article having a uniform outer diameter can be obtained. This heat treatment is carried out not only in one step but also at, for example, 1300 ° C. for 60 minutes, then
It is more effective to perform a two-step process such as holding at 00 for 60 minutes. At this time, the pressure reduction or vacuum atmosphere is 100 Pa or less, preferably 20 Pa or less. A uniform glass article can be obtained by heat-treating at the transparent vitrification temperature after the above first and second heat treatments. 100 Pa or less, preferably 20 Pa or less.
【００１２】本発明の方法を適用するガラス微粒子堆積
体の製法としては、ＶＡＤ法あるいはＯＶＤ法が挙げら
れる。例えばＶＡＤ法では、一般に同心円状多重管バー
ナーにより燃焼ガス例えば燃料としてＨ2 或いはＣ
Ｈ4 ，Ｃ3 Ｈ8 などの炭化水素ガス、支燃性ガスとして
Ｏ2 あるいは空気を燃焼させ火炎を形成し、この火炎中
にガラス原料としてガス状のＳｉＣｌ4 あるいはＳｉＨ
Ｃｌ3 またはＳｉ（ＯＣＨ 3 ）4 などのアルコキシドを
噴出することにより、火炎中野精製仏であるＨ2 Ｏある
いは過剰に流されるＯ2 と反応させることにより、ガラ
ス粒子のＳｉＯ2 を生成し、これをターゲットに堆積さ
せることにより、ガラス微粒子堆積体を作る。このガラ
ス微粒子堆積体はバーナーはの距離が一定になるように
ターゲットをバーナーに相対的にトラバースすることに
より長尺化し、ガラス微粒子堆積体を得る。また、本発
明のガラス微粒子堆積体の製法としては、ＳｉＯ2 の微
細な粒状ガラス粉（０．１〜１００μｍ）を熱間あるい
は常温で圧縮成形して多孔質ガラス体とする方法、ある
いは上記各方法により合成した後、希土類元素あるいは
屈折率を変えるドーパントを液浸あるいは熱処理により
含有させた多孔質ガラス体とする方法等種々の公知手段
を挙げることができる。本発明のガラス微粒子堆積体の
組成についてはＳｉＯ2 を主成分とするものであればい
ずれもよく、これに上記のように屈折率を変化させるド
ーパント例えばＧｅＯ2 、Ｂ2 Ｏ3 、Ｐ2 Ｏ5 あるいは
Ｆを添加したもの、希土類元素例えばＥｒ、Ｎｄなどを
ドープしたもの等各種の添加物を含むものであってよ
く、基本的に多孔質ガラス体であればよい。また本発明
におけるガラス微粒子堆積体としては、単なるガラス微
粒子堆積体のみからなるもの、中心部よりも外周部で屈
折率の低い少なくとも２重の導波路構造を持つガラス微
粒子堆積体、あるいはガラスロッドの外周に気相合成法
により更にガラス微粒子堆積体を合成した複合体であっ
てもよい。いずれにしても同等の効果が期待できる。中
心ガラスロッド−ガラス微粒子堆積体の複合体の場合、
中心部のガラスロッドは純石英ガラスに微量な不純物の
ドープされた石英ガラス、あるいは図４に示すようなコ
ア，クラッドを有する中心部に比べて外周部で屈折率の
低くなった少なくとも２重の導波路構造を有するような
光ファイバ用中間製造物である。Glass particulate deposition applying the method of the present invention
Examples of the body manufacturing method include the VAD method and the OVD method.
Be done. For example, in the VAD method, generally, a concentric multi-tube bar is used.
The combustion gas, for example H as fuel2Or C
HFour, C3H8As a hydrocarbon gas such as
O2Alternatively, when air is burned to form a flame,
Gaseous SiCl as a glass raw materialFourOr SiH
Cl3Or Si (OCH 3)FourSuch as alkoxide
H, which is a refined Buddha in flame Nakano,2There is O
O overflowed2By reacting with
Particle SiO2Generated and deposited on the target
By doing so, a glass particulate deposit is produced. This gala
As for the fine particle deposit, the distance of the burner should be constant.
To traverse the target relative to the burner
It is made longer and a glass particle deposit is obtained. Also,
As a method of manufacturing the glass particle deposit of Ming,2Fine
Heat fine granular glass powder (0.1-100 μm)
Is a method of compression molding at room temperature to form a porous glass body,
Alternatively, after synthesizing by the above methods, rare earth elements or
Immersion or heat treatment of the dopant that changes the refractive index
Various known means such as a method for forming a porous glass body
Can be mentioned. The glass particulate deposit of the present invention
Regarding composition, SiO2If the main component is
The deviation is good, and this is the reason why the refractive index changes as described above.
-Puntes such as GeO2, B2O3, P2OFiveOr
F added, rare earth elements such as Er, Nd, etc.
It may contain various additives such as doped ones.
Basically, any porous glass body may be used. The present invention
As a glass particle deposit in
Consists only of particle deposits, bending at the outer periphery rather than at the center
A glass microstructure with at least double waveguide structure with low bending rate
Vapor-phase synthesis method on the periphery of particle deposit or glass rod
Is a composite of glass particle deposits.
May be. In any case, the same effect can be expected. During ~
In the case of a composite of core glass rod-glass particulate deposit,
The glass rod in the center is made of pure silica glass with trace impurities.
Doped quartz glass, or
A, the refractive index in the outer peripheral part is higher than that in the central part with clad.
Such as having a lowered at least double waveguide structure
It is an intermediate product for optical fiber.
【００１３】[0013]
比較例１
ＶＡＤ法で合成したガラス微粒子堆積体（組成：純Ｓｉ
Ｏ2 母材）を真空雰囲気にて透明化した。ガラス微粒子
堆積体の寸法は、φ１５０ｍｍ×８００ｍｍのものを使
用した。図２に示す構成で、真空ポンプを用いて炉内圧
力を５Ｐａまで減圧し、温度を１６００℃まで８°／分
で昇温し、１６００℃で３０分間保持し、次に冷却後炉
から取り出した。この結果、外径は図３に示す如く変形
し、最大φ７２ｍｍ、中間部の最小部はφ６４ｍｍと大
きく変形してしまった。気泡についても、１０本焼結し
たうちの６本に全長にわたり気泡が見られ、上端部には
１０本とも気泡が存在した。Comparative Example 1 Glass fine particle deposited body synthesized by VAD method (composition: pure Si
The O 2 matrix was made transparent in a vacuum atmosphere. The size of the glass particulate deposit was φ150 mm × 800 mm. With the structure shown in FIG. 2, the pressure inside the furnace was reduced to 5 Pa using a vacuum pump, the temperature was raised to 1600 ° C. at 8 ° / min, and the temperature was maintained at 1600 ° C. for 30 minutes, then taken out from the furnace after cooling. It was As a result, the outer diameter was deformed as shown in FIG. 3, and the maximum diameter was 72 mm, and the minimum intermediate portion was 64 mm. Regarding bubbles, bubbles were seen over the entire length in 6 out of 10 sintered, and bubbles were present in all 10 at the upper end.
【００１４】実施例１
比較例と同様にＶＡＤ法で合成したガラス微粒子堆積体
（組成：純ＳｉＯ2母材）を本発明の構成に基づいて透
明化した。ガラス微粒子堆積体の寸法はφ１５０ｍｍ×
８００ｍｍのものを使用した。外径は個々で多少異なる
が、±２ｍｍの範囲内の精度で製造できていた。この母
材を図２の炉内に挿入し、炉内圧力を５Ｐａまで減圧
し、熱処理を行った。熱処理温度は１０５０℃まで８°
／分で昇温し、１０５０℃で６０分間保持、更に１３５
０℃まで８°／分で昇温し１３５０℃で６０分間保持、
最後に１６００℃まで昇温し３０分保持した後、降温し
た。この結果、得られたガラス物品は全長にわたり気泡
は見られず、良好な透明体であった。外径は全長にわた
ってφ６８ｍｍ±０．５ｍｍと非常に均一なものが得ら
れた。Example 1 A glass fine particle deposit (composition: pure SiO 2 base material) synthesized by the VAD method as in the comparative example was made transparent based on the constitution of the present invention. The size of the glass particle deposit is φ150 mm ×
The thing of 800 mm was used. The outer diameter was slightly different for each, but could be manufactured with an accuracy within a range of ± 2 mm. This base material was inserted into the furnace shown in FIG. 2, the furnace pressure was reduced to 5 Pa, and heat treatment was performed. Heat treatment temperature is 8 ° up to 1050 ° C
The temperature is raised at a rate of 1 / min and held at 1050 ° C for 60 minutes, then 135
Raise the temperature to 0 ° C at 8 ° / min and hold at 1350 ° C for 60 minutes,
Finally, the temperature was raised to 1600 ° C., held for 30 minutes, and then lowered. As a result, the obtained glass article was a good transparent body with no bubbles observed over the entire length. The outer diameter was φ68 mm ± 0.5 mm, which was very uniform over the entire length.
【００１５】実施例２
中心部にＧｅがドープされ屈折率を高くし、外周部に純
ＳｉＯ2 層を持つガラスロッドの周囲に、ＶＡＤ法によ
り図５のような構成でガラス微粒子堆積体を合成し、複
合体を製造した。この複合体の寸法はφ１５６ｍｍ×８
００ｍｍとなった。外径変動は１ｍｍ以内であった。こ
の複合体を実施例１と同様の条件で透明化したところ、
気泡は見られず、外径もφ６９ｍｍ±０．４ｍｍと良好
なものが得られた。このガラス物品はこの後光ファイバ
用プリフォームとして線引加工され、良好な光ファイバ
を得ることができた。Example 2 A glass fine particle deposit was synthesized by a VAD method around a glass rod having a central portion doped with Ge to have a high refractive index and having a pure SiO 2 layer on the outer peripheral portion, by the VAD method. Then, a composite was manufactured. The size of this composite is φ156mm × 8
It became 00 mm. The outer diameter variation was within 1 mm. When this composite was made transparent under the same conditions as in Example 1,
No bubbles were observed, and the outer diameter was as good as φ69 mm ± 0.4 mm. This glass article was then drawn as a preform for an optical fiber, and a good optical fiber could be obtained.
【００１６】比較例２
比較例１と同様のガラス微粒子堆積体を真空雰囲気にて
透明化した。温度条件は１０５０℃まで８℃／分で昇温
し、１０５０℃で６０分間保持した後、さらに１６００
℃まで８℃／分で昇温し３０分間保持した後、降温し
た。この条件で透明化した母材は、透明度は良好なもの
の、外径が変動しており、最大外径７３ｍｍ、中間部の
最小外径は６４ｍｍとなってしまった。Comparative Example 2 The same glass particle deposit as in Comparative Example 1 was made transparent in a vacuum atmosphere. The temperature condition was that the temperature was raised to 1050 ° C. at 8 ° C./min, held at 1050 ° C. for 60 minutes, and then 1600
The temperature was raised up to 8 ° C./min and kept for 30 minutes, and then lowered. The base material made transparent under these conditions had good transparency, but the outer diameter varied, and the maximum outer diameter was 73 mm and the minimum outer diameter of the intermediate portion was 64 mm.
【００１７】比較例３
比較例１と同様のガラス微粒子堆積体を真空雰囲気にて
透明化した。温度条件は１３５０℃まで８℃／分で昇温
し、１３５０℃で６０分間保持した後、さらに１６００
℃まで８℃／分で昇温し３０分間保持した後、降温し
た。この条件で透明化した母材は、外径は全長にわたり
１ｍｍ以内の変動に収まったものの、全長にわたり気泡
が残留してしまった。Comparative Example 3 The same glass particle deposit as in Comparative Example 1 was made transparent in a vacuum atmosphere. The temperature condition was that the temperature was raised up to 1350 ° C. at 8 ° C./min, held at 1350 ° C. for 60 minutes, and then 1600 ° C.
The temperature was raised up to 8 ° C./min and kept for 30 minutes, and then lowered. Although the outer diameter of the base material made transparent under these conditions was within 1 mm variation over the entire length, air bubbles remained over the entire length.
【００１８】実施例３
実施例１と同様のガラス微粒子堆積体を本発明に従い透
明化した。熱処理温度は１０５０℃まで８℃／分で昇温
し、１０５０℃で６０分間保持した後、更に１３５０℃
まて８℃／分で昇温し４０分間保持した。この後更に１
４５０℃まで６℃／分で昇温し３０分間保持したのち、
１６００℃まで８℃／分で昇温して透明ガラス化した。
この結果、得られたガラス物品は全長にわたり良好な透
明度を有し、気泡は全く見られなかった。また外径変動
も全長（有効部）にわたり±０．５ｍｍ以内におさま
り、高品質なガラス物品を得ることができた。以上の比
較例、実施例の結果を見れば、本発明によれば、従来よ
り寸法精度を向上して長手方向、径方向共に変動が少な
く、しかも気泡等の発生のない良好なガラスを得ること
ができることが、明らかにわかる。Example 3 The same glass particle deposit as in Example 1 was made transparent according to the present invention. The heat treatment temperature is raised to 1050 ° C at a rate of 8 ° C / min, and the temperature is kept at 1050 ° C for 60 minutes, and then 1350 ° C.
Furthermore, the temperature was raised at 8 ° C./min and held for 40 minutes. 1 more after this
After heating up to 450 ° C at 6 ° C / min and holding for 30 minutes,
The temperature was raised to 1600 ° C. at 8 ° C./minute to form a transparent glass.
As a result, the obtained glass article had good transparency over the entire length and no bubbles were observed. Further, the outer diameter variation was suppressed within ± 0.5 mm over the entire length (effective portion), and a high quality glass article could be obtained. Looking at the results of the above comparative examples and examples, according to the present invention, it is possible to obtain a good glass with improved dimensional accuracy and less fluctuation in the longitudinal direction and radial direction and generation of bubbles etc. It is clear that you can do it.
【００１９】[0019]
【発明の効果】以上説明したように、本発明によればガ
ラス微粒子堆積体の収縮が進行せず且つガスが活性化す
る温度範囲にて脱気できるため、透明化後のガラス物品
中に気泡の残留がなく、しかも透明化しない温度にて徐
々に収縮を進行させることができるため均一な収縮が実
現できて高品質のガラス物品を得ることができる。As described above, according to the present invention, since the glass particulate deposit can be degassed within the temperature range in which the shrinkage does not proceed and the gas is activated, air bubbles remain in the glass article after being transparentized. Since the shrinkage can be gradually promoted at a temperature at which the glass does not remain and the glass does not become transparent, uniform shrinkage can be realized and a high quality glass article can be obtained.
【図１】本発明の加熱処理を示す温度パターン図であ
る。FIG. 1 is a temperature pattern diagram showing a heat treatment of the present invention.
【図２】真空あるいは減圧下での透明化装置を説明する
概略図である。FIG. 2 is a schematic diagram illustrating a transparentizing device under vacuum or reduced pressure.
【図３】ガラス物品の長手方向の外径変動の様子を生命
する概略図である。FIG. 3 is a schematic diagram showing how the outer diameter of a glass article fluctuates in the longitudinal direction.
【図４】ガラスロッド−ガラス微粒子堆積体複合体に使
用するガラスロッド内の屈折率分布を示す図である。FIG. 4 is a diagram showing a refractive index distribution in a glass rod used for a glass rod-glass fine particle deposit composite body.
【図５】ＶＡＤ法によりガラス微粒子堆積体の合成を示
す概略図である。FIG. 5 is a schematic view showing the synthesis of a glass fine particle deposit by the VAD method.
【図６】従来の加熱処理の温度パターン図である。FIG. 6 is a temperature pattern diagram of a conventional heat treatment.
１１ ガラス微粒子堆積体 １２ 炉芯管 １３ ヒータ １４ ヒートシールド １５ 真空容器 １６ 脱気用配管 １７ 真空ポンプ ５１ ガラス微粒子生成用バーナ ５２ 火炎 ５３ ガラス微粒子堆積体 ５４ ガラスロッド 11 Glass particle deposit 12 Furnace core tube 13 heater 14 Heat shield 15 Vacuum container 16 Degassing piping 17 Vacuum pump 51 Burner for producing fine glass particles 52 flame 53 Glass particulate deposit 54 glass rod
Claims (3)
合成し、該ガラス微粒子堆積体を真空あるいは減圧雰囲
気で加熱処理することにより透明ガラス化してガラス物
品を製造する方法において、加熱処理としてガラス微粒
子堆積体が収縮をしない温度での第１の熱処理、第１の
熱処理より高く且つ透明ガラス化しない温度での第２の
熱処理、透明ガラス化する温度での第３の熱処理の少な
くとも３段階の熱処理を行うことを特徴とするガラス物
品の製造方法。1. A method for producing a glass article by synthesizing a glass fine particle deposit by a gas phase synthesis method and heating the glass particulate deposit to heat the glass in a vacuum or a reduced pressure atmosphere to produce a glass article. At least three steps of a first heat treatment at a temperature at which the fine particle deposit does not shrink, a second heat treatment at a temperature higher than the first heat treatment and at which transparent vitrification does not occur, and a third heat treatment at a temperature at which transparent vitrification occurs A method for manufacturing a glass article, which comprises performing a heat treatment.
℃、第２の熱処理温度が１２５０〜１５００℃、第３の
熱処理温度が１５５０℃〜１６５０℃であることを特徴
とする請求項１記載のガラス物品の製造方法。2. The first heat treatment temperature is 1000 to 1150.
C., the second heat treatment temperature is 1250 to 1500.degree. C., and the third heat treatment temperature is 1550.degree. C. to 1650.degree.
周部で屈折率の低い、少なくとも２重の導波路構造を持
つガラスロッドの外周に気相合成法により更にガラス微
粒子堆積体を合成した複合体であることを特徴とする請
求項１または２記載のガラス物品の製造方法。3. The glass particle deposit is further synthesized by a vapor phase synthesis method on the outer periphery of a glass rod having a waveguide structure in which the refractive index is lower in the outer peripheral portion than in the central portion and has at least double waveguide structure. It is a composite, The manufacturing method of the glass article of Claim 1 or 2 characterized by the above-mentioned.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3179814A JP2836302B2 (en) | 1991-07-19 | 1991-07-19 | Method for manufacturing glass articles |
| AU19688/92A AU653411B2 (en) | 1991-07-19 | 1992-07-15 | Method for producing glass preform for optical fiber |
| EP92112148A EP0523692B2 (en) | 1991-07-19 | 1992-07-16 | Method for producing glass preform for optical fiber |
| DE69209174T DE69209174T3 (en) | 1991-07-19 | 1992-07-16 | Process for making an optical fiber preform |
| US07/913,965 US5330548A (en) | 1991-07-19 | 1992-07-17 | Method for producing glass preform for optical fiber |
| KR1019920012835A KR940011118B1 (en) | 1991-07-19 | 1992-07-18 | Method of producing glass preform for optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3179814A JP2836302B2 (en) | 1991-07-19 | 1991-07-19 | Method for manufacturing glass articles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0524854A true JPH0524854A (en) | 1993-02-02 |
| JP2836302B2 JP2836302B2 (en) | 1998-12-14 |
Family
ID=16072358
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3179814A Expired - Lifetime JP2836302B2 (en) | 1991-07-19 | 1991-07-19 | Method for manufacturing glass articles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2836302B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5656057A (en) * | 1995-05-19 | 1997-08-12 | Corning Incorporated | Method for drying and sintering an optical fiber preform |
| WO2000012438A1 (en) * | 1998-08-31 | 2000-03-09 | Sumitomo Electric Industries, Ltd. | Method of producing glass article and glass base material for optical fiber |
| US6050108A (en) * | 1997-09-08 | 2000-04-18 | Sumitomo Electric Industries, Ltd. | Method for producing glass preform |
| US6438999B1 (en) * | 1997-07-15 | 2002-08-27 | Corning Incorporated | Decreased H2 sensitivity in optical fiber |
-
1991
- 1991-07-19 JP JP3179814A patent/JP2836302B2/en not_active Expired - Lifetime
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5656057A (en) * | 1995-05-19 | 1997-08-12 | Corning Incorporated | Method for drying and sintering an optical fiber preform |
| US6438999B1 (en) * | 1997-07-15 | 2002-08-27 | Corning Incorporated | Decreased H2 sensitivity in optical fiber |
| US6687444B2 (en) | 1997-07-15 | 2004-02-03 | Corning Incorporated | Decreased H2 sensitivity in optical fiber |
| US6050108A (en) * | 1997-09-08 | 2000-04-18 | Sumitomo Electric Industries, Ltd. | Method for producing glass preform |
| WO2000012438A1 (en) * | 1998-08-31 | 2000-03-09 | Sumitomo Electric Industries, Ltd. | Method of producing glass article and glass base material for optical fiber |
| AU755861B2 (en) * | 1998-08-31 | 2003-01-02 | Sumitomo Electric Industries, Ltd. | Method of producing glass article and glass base material for optical fiber |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2836302B2 (en) | 1998-12-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0473104B1 (en) | Method for manufacturing a silica glass base material | |
| JP2917729B2 (en) | Manufacturing method of optical fiber preform | |
| EP0176263B1 (en) | Optical fiber | |
| US11577984B2 (en) | Method for manufacturing optical fiber preform, optical fiber preform, method for manufacturing optical fiber, and optical fiber | |
| EP0523692B1 (en) | Method for producing glass preform for optical fiber | |
| US6732549B1 (en) | Multi-pass sintering of a sol-gel body through a hot zone | |
| JP2836302B2 (en) | Method for manufacturing glass articles | |
| JP4865232B2 (en) | Optical fiber preform manufacturing method | |
| JPWO2002102725A1 (en) | Manufacturing method of glass base material and glass base material | |
| AU755861B2 (en) | Method of producing glass article and glass base material for optical fiber | |
| JPS6086047A (en) | Manufacture of glass preform for optical fiber | |
| JPH06263468A (en) | Production of glass base material | |
| JP2985493B2 (en) | Manufacturing method of optical fiber preform | |
| JP4403623B2 (en) | Optical fiber preform manufacturing method | |
| US20220081345A1 (en) | Manufacturing method of glass base material for optical fiber | |
| JPH028973B2 (en) | ||
| JP2770103B2 (en) | Manufacturing method of optical fiber preform | |
| JPS63151639A (en) | Production of glass preformer for optical fiber | |
| JP3439258B2 (en) | Method for producing glass preform for optical fiber | |
| JPS62171937A (en) | Production of glass article | |
| JP2003054958A (en) | Method for manufacturing glass article | |
| JPS63285128A (en) | Production of optical fiber preform | |
| JP2003286034A (en) | Method for manufacturing glass preform | |
| JP2003137582A (en) | Method for manufacturing optical fiber preform | |
| JPH0710571A (en) | Production of synthetic quartz glass member |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20071009 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081009 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091009 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101009 Year of fee payment: 12 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111009 Year of fee payment: 13 |
|
| EXPY | Cancellation because of completion of term |