JPH06271321A - Production of glass body - Google Patents

Production of glass body

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Publication number
JPH06271321A
JPH06271321A JP8667393A JP8667393A JPH06271321A JP H06271321 A JPH06271321 A JP H06271321A JP 8667393 A JP8667393 A JP 8667393A JP 8667393 A JP8667393 A JP 8667393A JP H06271321 A JPH06271321 A JP H06271321A
Authority
JP
Japan
Prior art keywords
furnace
gas
porous body
pressure
glass body
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.)
Withdrawn
Application number
JP8667393A
Other languages
Japanese (ja)
Inventor
Hiroaki Kinoshita
博章 木下
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Olympus Corp
Original Assignee
Olympus Optical Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Olympus Optical Co Ltd filed Critical Olympus Optical Co Ltd
Priority to JP8667393A priority Critical patent/JPH06271321A/en
Publication of JPH06271321A publication Critical patent/JPH06271321A/en
Withdrawn legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B32/00—Thermal after-treatment of glass products not provided for in groups C03B19/00, C03B25/00 - C03B31/00 or C03B37/00, e.g. crystallisation, eliminating gas inclusions or other impurities; Hot-pressing vitrified, non-porous, shaped glass products

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  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Glass Melting And Manufacturing (AREA)
  • Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)

Abstract

PURPOSE:To obtain a glass body excellent in light transmittance in a short time without generating bubbles in the glass body. CONSTITUTION:A glass body is produced by heat-treating a porous body. At the time of treat-treating the porous body in a furnace, the gas in the furnace is discharged to attain reduced pressure, gas of the same kind is blown into the furnace and the porous body is heat-treated. This process is preferably repeated plural times. The degree of reduced pressure is preferably increased in accordance with the repetition of heat treatment..

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、光学素子などの高い光
透過率を有するガラス体の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a glass body having a high light transmittance such as an optical element.

【０００２】[0002]

【従来の技術】ガラス体を作製する際の前駆体として使
用される多孔質体は、ゾル・ゲル法や化学気相法（ＣＶ
Ｄ法、ＶＡＤ法）によって作製されている。多孔質体を
熱処理してガラス体を得るというプロセスにより作製さ
れる高純度シリカガラスは、半導体の製造の際に使用さ
れるるつぼやボート、拡散炉などへの応用が考えられて
おり、多くの研究がされている。しかし、多孔質体から
バルク体を作製するには、気泡の発生無しに焼成するこ
とは困難であるという問題がある。2. Description of the Related Art A porous body used as a precursor for producing a glass body is a sol-gel method or a chemical vapor deposition method (CV).
D method, VAD method). High-purity silica glass produced by the process of heat-treating a porous body to obtain a glass body is considered to be applied to crucibles, boats, diffusion furnaces, etc. used in the production of semiconductors, and many Research is being done. However, in order to manufacture a bulk body from a porous body, it is difficult to perform firing without generating bubbles.

【０００３】気泡は、多孔質体中の気孔が無孔化する際
に生じる。多孔質のゲルを昇温して焼結すると、Ｓｉ−
ＯＨの脱水重縮合反応が進行して最初に閉孔が形成され
るが、これらの閉孔は、ヘリウムのような高い拡散性を
もつガス雰囲気中で高温度で熱処理することにより、気
孔のない透明なガラス体を形成するようにつぶれること
が知られている（Ｓ．Ｓａｔｏｈ ｅｔ ａｌ，Ｊｏｕ
ｒｎａｌ ｏｆ Ｎｏｎ−Ｃｒｙｓｔａｌｌｉｎｅ Ｓ
ｏｌｉｄｓ ５５（１９８３），ｐ４５５−ｐ４５
７）。従来、この特性を利用したものとして、多孔質Ｓ
ｉＯ2 を焼成の際に６００℃から８００℃の範囲を不活
性ガス雰囲気または保護雰囲気（特にヘリウムガス雰囲
気）で熱処理する方法（特開昭６１−２９５２４３号公
報）、９００℃から１４００℃までをヘリウムガス雰囲
気で焼結する方法（特開昭６１−２３６６１７号公
報）、ヘリウムガスが導入された減圧下で焼結する方法
（特公昭６４−３３０号公報）などがある。Bubbles are generated when the pores in the porous body become non-porous. When the porous gel is heated and sintered, Si-
The dehydration polycondensation reaction of OH progresses to form closed pores first, but these closed pores are free from pores when heat-treated at a high temperature in a gas atmosphere having high diffusivity such as helium. It is known to collapse to form a transparent glass body (S. Satoh et al, Jou.
rnal of Non-Crystalline S
olds 55 (1983), p455-p45
7). Conventionally, the porous S has been used to utilize this characteristic.
A method of heat treating io 2 in the range of 600 ° C. to 800 ° C. in an inert gas atmosphere or a protective atmosphere (in particular, a helium gas atmosphere) (JP-A-61-295243), 900 ° C. to 1400 ° C. There are a method of sintering in a helium gas atmosphere (Japanese Patent Laid-Open No. 61-236617), a method of sintering under a reduced pressure in which helium gas is introduced (Japanese Patent Publication No. 64-330).

【０００４】[0004]

【発明が解決しようとする課題】しかしながら、上記従
来の各方法では、多孔質体から発生した水分が再び多孔
質体の気孔や表面に吸着するために、多孔質体中の水分
の除去が十分に行われない場合があり、効果的に気泡の
発生を防止することが困難であった。特開昭６１−２９
５２４３号公報や特開昭６１−２３６６１７号公報記載
の方法では、多孔質体が焼結される際に発生した水分
が、炉の内部に溜って系外へ除去されにくいため、結果
として炉内が水蒸気を含んだヘリウムガス雰囲気となっ
てしまい、水分が再び焼結体の表面や細孔中に吸着した
状態で焼成されることになる。この水分がガラス中に微
小な気泡となる原因となっていた。また、特公昭６４−
３３０号公報記載の方法では、焼結の際に減圧したヘリ
ウムガス雰囲気中の密閉系で熱処理する。つまり、炉内
部を減圧して熱処理を行うので、熱を伝達するキャリア
ーガスの濃度が希薄であり、発熱体から発せられた熱の
伝導率が悪く、焼結に時間がかかるという欠点をもって
おり、さらに密閉系で焼結を行うので、多孔質体から発
生した水分が系外に排出されず、前述のように微小な気
泡の発生の原因となっていた。However, in each of the above-mentioned conventional methods, since the water generated from the porous body is adsorbed again to the pores and the surface of the porous body, the water in the porous body is sufficiently removed. However, it is difficult to effectively prevent the generation of bubbles. JP-A-61-29
In the method described in Japanese Patent No. 5243 or Japanese Patent Application Laid-Open No. 61-236617, the water generated when the porous body is sintered is not easily collected outside the system because of being accumulated inside the furnace. Becomes a helium gas atmosphere containing water vapor, and is fired in a state where water is adsorbed again on the surface of the sintered body or in the pores. This water was a cause of forming minute bubbles in the glass. In addition,
In the method described in Japanese Patent No. 330, heat treatment is performed in a closed system in a helium gas atmosphere whose pressure is reduced during sintering. In other words, since the heat treatment is performed by reducing the pressure inside the furnace, the concentration of the carrier gas that transfers heat is low, the conductivity of the heat emitted from the heating element is poor, and it takes a long time to sinter. Further, since the sintering is performed in a closed system, the water generated from the porous body is not discharged out of the system, which causes the generation of minute bubbles as described above.

【０００５】すなわち、従来の方法では、これらの原因
により、機械的には強固なガラス体が得られても、非常
に微小な気泡がガラス体中に残留する。そして、これら
の気泡が光の散乱を起こして光学特性を悪化させる原因
となったり、所望のガラス体を得るために必要な熱処理
が長時間になるといった欠点を有していた。That is, in the conventional method, even if a glass body that is mechanically strong is obtained by these causes, very fine bubbles remain in the glass body. These bubbles have the drawbacks of causing light scattering and deteriorating the optical characteristics, and of requiring a long heat treatment to obtain a desired glass body.

【０００６】本発明は、かかる従来の問題点に鑑みてな
されたものであり、ガラス体中に気泡が発生せず、光透
過率に優れたガラス体を短時間で得ることができるガラ
ス体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-mentioned conventional problems, and a glass body capable of obtaining a glass body excellent in light transmittance in a short time without generating bubbles in the glass body. It is intended to provide a manufacturing method.

【０００７】[0007]

【課題を解決するための手段】上記課題を解決するため
に、本発明は、多孔質体を加熱処理することによりガラ
ス体を作製するガラス体の製造方法において、多孔質体
を加熱処理する際に、炉内部の気体を排気して減圧した
後、炉内部に同種の気体を注入して熱処理する工程を有
することとした。In order to solve the above-mentioned problems, the present invention provides a method for producing a glass body, in which a glass body is produced by heat-treating the porous body. In addition, after the gas inside the furnace was exhausted to reduce the pressure, the same kind of gas was injected into the inside of the furnace to perform heat treatment.

【０００８】上記本発明のガラス体の製造方法におい
て、炉内部の気体を排気して減圧した後、再び炉内部に
気体を注入して熱処理する工程は、複数回繰り返すとよ
い。図１は、このような排気を繰り返す工程において、
熱処理温度と炉内の圧力との関係を示すグラフである。
図１において、実線が温度変化を、破線が圧力変化を示
す。In the method for producing a glass body of the present invention, the step of exhausting the gas inside the furnace to reduce the pressure and then injecting the gas into the furnace again for heat treatment may be repeated a plurality of times. In FIG. 1, in the process of repeating such exhaust,
It is a graph which shows the relationship between heat processing temperature and the pressure in a furnace.
In FIG. 1, the solid line shows the temperature change and the broken line shows the pressure change.

【０００９】また、複数回繰り返す場合に、２回目以降
の前記熱処理工程における減圧は、前回よりさらに減圧
するとよい。図２は、このように排気を繰り返す工程に
おいて、減圧度を排気する度に大きくする場合の熱処理
温度と炉内の圧力との関係を示すグラフである。図２に
おいて、実線が温度変化を、破線が圧力変化を示す。Further, when it is repeated a plurality of times, the pressure reduction in the second and subsequent heat treatment steps may be further reduced than the previous pressure reduction. FIG. 2 is a graph showing the relationship between the heat treatment temperature and the pressure in the furnace when the degree of pressure reduction is increased each time the gas is exhausted in the process of repeating the exhaustion. In FIG. 2, the solid line shows the temperature change and the broken line shows the pressure change.

【００１０】なお、減圧過程・常圧過程は、ゲルを温度
保持している時に行っても良いし、昇温中に行っても良
い。ここで、前記減圧過程において、図３に示すよう
に、炉内を急激に排気してから熱処理を行う工程と、図
４に示すように、炉内を徐々に排気しながら熱処理を行
う工程の両方を含む。The depressurization process and the normal pressure process may be performed while the temperature of the gel is maintained, or during the temperature rise. Here, in the depressurizing process, as shown in FIG. 3, a step of performing a heat treatment after rapidly exhausting the inside of the furnace and a step of performing a heat treatment while gradually exhausting the inside of the furnace as shown in FIG. Including both.

【００１１】[0011]

【作用】ゾル・ゲル法やＶＡＤ法などにより作製された
多孔質体は、水を多量に含有している。したがって、こ
の多孔質体を熱処理することによってガラス化を行う際
には、ゲルの細孔中や表面に吸着していた水分の蒸発
と、無孔化にともなうシラノール基の脱水反応により発
生した水分の蒸発を伴う。The porous body produced by the sol-gel method or the VAD method contains a large amount of water. Therefore, when performing vitrification by heat-treating this porous body, evaporation of water adsorbed in the pores and the surface of the gel and water generated by dehydration reaction of silanol groups accompanying non-pore formation With evaporation of.

【００１２】多孔質体の焼成には、多孔質体中に存在す
る水分の量を減少させることと、シラノール基の脱水反
応により発生した水分の除去を効果的に行うことが重要
である。なぜなら、熱処理温度がある程度高くなると、
Ｓｉ−ＯＨの脱水縮合反応が進行し、多孔質体中の開孔
がなくなってしまうために、閉孔後まで多孔質体中に残
留する水分および閉孔が収縮する時に発生する水分がガ
ス化し、そのガスの圧力により発泡するからである。焼
成時に多孔質体中の水分の除去が十分に行われなかった
り、多孔質体から発生した水分が再び多孔質体の気孔や
表面に吸着すると、閉孔内に水分が残留してガラスが発
泡する原因となる。For the firing of the porous body, it is important to reduce the amount of water present in the porous body and effectively remove the water produced by the dehydration reaction of the silanol groups. Because when the heat treatment temperature rises to some extent,
Since the dehydration condensation reaction of Si-OH proceeds and the open pores in the porous body disappear, the water remaining in the porous body until after the closing and the water generated when the closed pores contract are gasified. , Because the pressure of the gas causes foaming. If water in the porous body is not sufficiently removed during firing, or if the water generated from the porous body is adsorbed again on the pores or the surface of the porous body, the water remains inside the closed pores and the glass foams. Cause

【００１３】本発明の方法を用いると、次のような効果
がある。無孔化の際に、例えばヘリウムガス雰囲気を用
いて焼成するが、これを常圧で行うことにより、ヘリウ
ムガスがゲル中を拡散して熱を伝えるキャリアーとして
十分機能し、ガラスの中心部まで熱を伝導して多孔質体
中のシラノール基の脱水縮合を促進する。また、ヘリウ
ムガスは、脱水縮合にともなって発生する水分を系外に
排出する役割をもつ。開孔がつぶれて閉孔になり、ヘリ
ウムガスが閉孔中に閉じ込められるが、ヘリウムガスは
酸素ガスや空気に比べてＳｉＯ2 骨格への透過率が大き
いことから、閉孔中に閉じ込められていたヘリウムガス
はＳｉＯ2 骨格中を拡散することができるので、最終的
に閉孔をつぶすことができる。The use of the method of the present invention has the following effects. When non-porous, it is fired, for example, in a helium gas atmosphere, but by performing this at normal pressure, the helium gas diffuses in the gel and functions sufficiently as a carrier to transfer heat to the center of the glass. Conducts heat to promote dehydration condensation of silanol groups in the porous body. In addition, the helium gas has a role of discharging moisture generated by dehydration condensation out of the system. The opening is crushed to become a closed hole, and helium gas is confined in the closed hole. However, since helium gas has a higher permeability to the SiO 2 skeleton than oxygen gas or air, it is confined in the closed hole. Since helium gas can diffuse in the SiO 2 skeleton, the closed holes can be finally closed.

【００１４】従来、常圧でヘリウムガスを流し続けるこ
とによって炉内にある水分を含んだヘリウムガスを排気
することは膨大な時間がかかり、迅速に炉内の水分を除
去することは不可能であった。しかし、本発明の方法、
つまりヘリウムガスで熱処理を行った後、炉内の減圧排
気を繰り返す工程（一度ヘリウムガス雰囲気で焼結をし
ておいて、その後炉内を減圧して多孔質体から発生した
水分を含んだヘリウムガスを排気しておき、あらたにヘ
リウムガスを加えて焼成する工程）を行うと、焼成時に
おけるヘリウムガスが常に水分を含まない状態を効率よ
く保つことが可能である。このため、多孔質体に水分が
気孔や表面に再吸着したり、Ｓｉ−０−Ｓｉの網目結合
が切断されて再びシラノール基が再生成することを抑制
することができる。さらに、炉内を減圧した雰囲気中で
多孔質体を加熱するので、水の蒸気圧を低下させ、多孔
質体の細孔中に吸着した水分の除去をより効果的に行う
ことが可能である。以上のことから、減圧排気の後、ヘ
リウムガスを注入して熱処理する工程を繰り返すことに
より、より有効な水分の除去ができ、ひいては多孔質体
をガラス化する際に発生する気泡の発生を防止すること
ができる。Conventionally, it takes an enormous amount of time to exhaust the helium gas containing water in the furnace by continuously flowing the helium gas at normal pressure, and it is impossible to quickly remove the water in the furnace. there were. However, the method of the invention,
In other words, after heat-treating with helium gas, the step of repeatedly depressurizing and exhausting the inside of the furnace (sintering once in a helium gas atmosphere, then depressurizing the inside of the furnace and helium containing water generated from the porous body) It is possible to efficiently keep the state in which the helium gas does not always contain water at the time of firing by performing the step of firing the gas by exhausting the gas and newly adding helium gas. Therefore, it is possible to prevent moisture from being re-adsorbed to the pores and the surface of the porous body, and the re-generation of the silanol group due to breaking of the Si-0-Si network bond. Furthermore, since the porous body is heated in a reduced pressure atmosphere in the furnace, it is possible to reduce the vapor pressure of water and more effectively remove the water adsorbed in the pores of the porous body. . From the above, by repeating the process of injecting helium gas and heat-treating after depressurization exhaust, more effective water removal can be performed, and eventually the generation of bubbles when vitrifying a porous body is prevented. can do.

【００１５】さらに大きな効果がもたらす手段として
は、図２に示すように、前記温度保持過程および排気工
程を複数回繰り返し、排気する度に炉内の減圧度を大き
くしていくことが考えられるが、この手段により段階的
に水の蒸発をコントロールすることができるため、多孔
質体に大きな応力をかけることなく、より効果的に水分
の除去を行うことができ、焼結時間を短縮することが可
能となる。As a means to bring about a further great effect, as shown in FIG. 2, it is considered that the temperature holding process and the exhaust process are repeated a plurality of times, and the degree of pressure reduction in the furnace is increased each time the exhaust is performed. Since the evaporation of water can be controlled stepwise by this means, it is possible to remove water more effectively without applying a large stress to the porous body and shorten the sintering time. It will be possible.

【００１６】なお、前記図３に示したように、炉内を急
激に排気してから熱処理を行う場合、多孔質体に含まれ
る水分を短時間で除去することができる。また、前記図
４に示したように、炉内を徐々に排気しながら熱処理を
行う場合、多孔質体中に含まれる水分の蒸発を少量ず
つ、かつ連続的に行うことができ、多孔質体に大きな応
力をかけることがないため、ゲルを破壊することなく焼
結を行うことができる。これらの減圧排気工程は、多孔
質体中に含まれる水分量や多孔質体の強度を鑑みて適宜
選択すれば良い。As shown in FIG. 3, when the heat treatment is performed after the furnace is rapidly evacuated, the water contained in the porous material can be removed in a short time. Further, as shown in FIG. 4, when the heat treatment is performed while gradually exhausting the inside of the furnace, the water contained in the porous body can be evaporated little by little and continuously. Since a large stress is not applied to, the sintering can be performed without breaking the gel. These vacuum exhaust steps may be appropriately selected in consideration of the amount of water contained in the porous body and the strength of the porous body.

【００１７】また、本発明は、次に述べるようなガラス
体の黒色着色という課題に対しても有効である。乾燥ゲ
ル中に含まれる残留有機物は主に未反応のアルコキシ基
によるものであり、酸素分圧の高い雰囲気中で加熱すれ
ば、これらの有機物は気体となって系外に出るが、酸素
分圧が低いと、蒸焼きになって、炭素の形でゲル内部に
残り、黒色に着色すると報告されている（ゾル・ゲル法
によるガラス・セラミックスの製造技術とその応用、山
根正之監著、ｐ１５４〜ｐ１５６、応用技術出版（１９
８９））。本発明の手段を、この有機物の燃焼工程に応
用することにより有効な効果が得られる。つまり、酸素
または空気などの酸素を含む混合気体を使用して有機物
の燃焼を行う工程において、気体の減圧排気，気体の再
注入を繰り返すことにより、先に説明した多孔質体中の
水分の除去と同様に、有機物の分解によって発生した水
分や炭素化合物の除去を迅速かつ確実に行うことができ
る。The present invention is also effective for the following problem of black coloring of the glass body. The residual organic substances contained in the dry gel are mainly due to unreacted alkoxy groups, and if heated in an atmosphere with a high oxygen partial pressure, these organic substances become a gas and go out of the system. If it is low, it will be steamed and will remain inside the gel in the form of carbon and will be colored black (Glass-ceramics manufacturing technology by the sol-gel method and its application, written by Masayuki Yamane, p154-). p156, Applied Technology Publishing (19
89)). Effective effects can be obtained by applying the means of the present invention to the combustion process of this organic substance. That is, in the step of burning an organic substance using oxygen or a mixed gas containing oxygen such as air, by repeatedly depressurizing the gas and reinjecting the gas, the removal of water in the porous body described above is performed. Similarly to the above, it is possible to quickly and surely remove the water and carbon compounds generated by the decomposition of the organic matter.

【００１８】[0018]

【実施例１】シリカ原料にＳｉ（ＯＣ2 Ｈ5 ）4 を使用
した。Ｓｉ（ＯＣ2 Ｈ5 ）4 １０．６ｇにエタノール１
８．４ｇを加えて１時間撹拌した後、水１０ｍｌと１規
定塩酸３ｍｌとを混合した溶液を滴下してゾルを得た。
このゾルを直径１８ｍｍのポリプロピレンチューブ容器
にキャスティングして、５０℃の恒温槽で放置し、ゲル
化させた後、さらに熟成し、乾燥して多孔質の乾燥ゲル
を得た。Example 1 Si (OC 2 H 5 ) 4 was used as a silica raw material. 10.6 g of Si (OC 2 H 5 ) 4 and 1 part of ethanol
After adding 8.4 g and stirring for 1 hour, a solution obtained by mixing 10 ml of water and 3 ml of 1N hydrochloric acid was added dropwise to obtain a sol.
This sol was cast in a polypropylene tube container having a diameter of 18 mm, left in a constant temperature bath at 50 ° C. for gelation, further aged, and dried to obtain a porous dry gel.

【００１９】この多孔質ゲルを空気中で２５０℃まで昇
温してから５時間保持し、６００℃まで昇温して５時間
保持した。この後、空気をヘリウムガスに置換し、９０
０℃まで昇温して４時間保持してから、炉内を排気して
１０ｍｍＨｇまで減圧し、３時間保持した後、再びヘリ
ウムガスを常圧まで注入して３時間保持し、炉内で徐冷
した。この熱処理によって得られたガラス体は、無色透
明であり、レーザー光をあてても散乱のない光透過性に
優れたガラスであった。This porous gel was heated to 250 ° C. in air and held for 5 hours, and then heated to 600 ° C. and held for 5 hours. After this, the air is replaced with helium gas,
After raising the temperature to 0 ° C and holding it for 4 hours, exhausting the inside of the furnace to reduce the pressure to 10 mmHg, holding it for 3 hours, then injecting helium gas to normal pressure again and holding it for 3 hours, and then slowly holding it in the furnace. Chilled The glass body obtained by this heat treatment was colorless and transparent, and was a glass having excellent light transmittance without scattering even when irradiated with a laser beam.

【００２０】（比較例１）実施例１と同様にして作製し
た多孔質の乾燥ゲルを空気中で２５０℃まで昇温してか
ら５時間保持し、６００℃まで昇温して５時間保持し
た。この後、空気をヘリウムガスに置換し、９００℃ま
で昇温して１０時間保持し、炉内で徐冷した。この熱処
理によって得られたガラス体は、肉眼で見るかぎり無色
透明であったが、レーザー光にあてると散乱が観察さ
れ、ガラス体中に微小な気泡が存在することがわかっ
た。Comparative Example 1 A porous dry gel prepared in the same manner as in Example 1 was heated in air to 250 ° C. and held for 5 hours, and then heated to 600 ° C. and held for 5 hours. . Then, the air was replaced with helium gas, the temperature was raised to 900 ° C., the temperature was maintained for 10 hours, and the furnace was gradually cooled. The glass body obtained by this heat treatment was colorless and transparent as far as the naked eye could see, but when exposed to laser light, scattering was observed, and it was found that minute bubbles were present in the glass body.

【００２１】[0021]

【実施例２】シリカ、ジルコニア原料にそれぞれＳｉ
（ＯＣＨ3 ）4 、Ｚｒ（Ｏn Ｃ4 Ｈ9）4 を使用した。
Ｓｉ（ＯＣＨ3 ）4 １０．６ｇにエタノール９．２ｇと
１規定塩酸１．２６ｇとを加えて３０℃で１時間撹拌
し、その溶液にＺｒ（Ｏn Ｃ4 Ｈ9 ）4 ５．７５ｇとイ
ソプロパノール１５．０ｇとを混合した溶液を添加して
１時間撹拌した後、水１５ｍｌと１規定硝酸３ｍｌとエ
タノール２３．０ｇとを混合した溶液を滴下してゾルを
得た。このゾルを直径１８ｍｍのポリプロピレンチュー
ブ容器にキャスティングして、５０℃の恒温槽で放置
し、ゲル化させた後、さらに熟成し、乾燥して多孔質の
乾燥ゲルを得た。[Embodiment 2] Si and zirconia are used as raw materials for Si
(OCH 3 ) 4 and Zr (O n C 4 H 9 ) 4 were used.
To 10.6 g of Si (OCH 3 ) 4 were added 9.2 g of ethanol and 1.26 g of 1N hydrochloric acid, and the mixture was stirred at 30 ° C. for 1 hour, and the solution was added with Zr (O n C 4 H 9 ) 4 5.75 g. After adding a solution mixed with 15.0 g of isopropanol and stirring for 1 hour, a solution obtained by mixing 15 ml of water, 3 ml of 1N nitric acid and 23.0 g of ethanol was added dropwise to obtain a sol. This sol was cast in a polypropylene tube container having a diameter of 18 mm, left in a constant temperature bath at 50 ° C. for gelation, further aged, and dried to obtain a porous dry gel.

【００２２】この多孔質体を、酸素ガスを常温で連続的
に流しながら２５０℃で３時間保持した後、１時間排気
して１０ｍｍＨｇまで減圧し、その後酸素ガスを常圧ま
で注入して１時間保持し、１時間排気して１ｍｍＨｇま
で減圧した。次に、常圧までヘリウムガスを注入して７
００℃で３時間保持し、７００℃で１時間排気して１０
ｍｍＨｇまで減圧した後、ヘリウムガスを常圧まで注入
して１時間保持し、１時間排気して１ｍｍＨｇまで減圧
した。この後、さらにヘリウムガスを注入して常圧で９
００℃まで昇温して３時間保持し、炉内で徐冷した。こ
の熱処理によって得られたガラス体は、無色透明であ
り、レーザー光をあてても散乱のない光透過性に優れた
ガラスであった。The porous body was kept at 250 ° C. for 3 hours while continuously flowing oxygen gas at room temperature, then evacuated for 1 hour and decompressed to 10 mmHg, and then oxygen gas was injected to normal pressure for 1 hour. It was held, exhausted for 1 hour, and depressurized to 1 mmHg. Next, inject helium gas up to atmospheric pressure to obtain 7
Hold at 00 ° C for 3 hours and evacuate at 700 ° C for 1 hour.
After the pressure was reduced to mmHg, helium gas was injected to normal pressure, held for 1 hour, evacuated for 1 hour, and reduced to 1 mmHg. After this, helium gas was further injected to bring the pressure to 9
The temperature was raised to 00 ° C., maintained for 3 hours, and then gradually cooled in the furnace. The glass body obtained by this heat treatment was colorless and transparent, and was a glass having excellent light transmittance without scattering even when irradiated with a laser beam.

【００２３】[0023]

【実施例３】シリカ、チタニア原料にそれぞれＳｉ（Ｏ
Ｃ2 Ｈ5 ）4 、高純度化学研究所製の二酸化チタン（ア
ナターゼ型）を使用した。Ｓｉ（ＯＣ2 Ｈ5 ）4 １０．
６ｇにエタノール９．２ｇと１規定塩酸１．２６ｇとを
加えて３０℃で１時間撹拌した。その溶液に、ＴｉＯ2
粒子６．２ｇを超音波でエタノール１５．０ｇに分散さ
せた溶液を添加して１時間撹拌し、その後水１５ｍｌと
１規定硝酸３ｍｌとエタノール１５．０ｇとを混合した
溶液を添加してゾルを得た。このゾルを直径１８ｍｍの
ポリプロピレンチューブ容器にキャスティングして、３
０℃の恒温槽で放置し、ゲル化させた後、さらに熟成
し、乾燥して多孔質の乾燥ゲルを得た。Example 3 Si (O) is used as a raw material for silica and titania, respectively.
C 2 H 5 ) 4 and titanium dioxide (anatase type) manufactured by Kojundo Chemical Laboratory Co., Ltd. were used. Si (OC 2 H 5 ) 4 10.
To 6 g, 9.2 g of ethanol and 1.26 g of 1N hydrochloric acid were added, and the mixture was stirred at 30 ° C. for 1 hour. TiO 2 was added to the solution.
A solution prepared by ultrasonically dispersing 6.2 g of particles in 15.0 g of ethanol was added and stirred for 1 hour, and then a solution of 15 ml of water, 3 ml of 1N nitric acid and 15.0 g of ethanol was added to form a sol. Obtained. This sol was cast into a polypropylene tube container with a diameter of 18 mm and
The gel was left to stand in a constant temperature bath at 0 ° C., gelled, further aged, and dried to obtain a porous dry gel.

【００２４】この多孔質体の乾燥ゲルを、酸素ガスを常
温で連続的に流しながら２５０℃まで熱処理した後、炉
内を排気して１０ｍｍＨｇまで減圧し、１時間保持し
た。再び酸素ガスを注入して常圧で１時間保持し、排気
して１ｍｍＨｇまで減圧し、１時間保持した。この後、
酸素ガスを常圧まで注入して６００℃で３時間保持し、
排気して１０ｍｍＨｇまで減圧し、１時間保持した。さ
らに、酸素ガスを常圧まで注入して１時間保持し、１ｍ
ｍＨｇまで減圧して１時間保持した。その後、酸素ガス
をヘリウムガスに置換して常圧に戻し、９００℃まで昇
温して３時間保持した後、８５０℃で排気して１０ｍｍ
Ｈｇまで減圧し、ヘリウムガスを常圧まで注入して９０
０℃で３時間保持した。この後、排気して１ｍｍＨｇま
で減圧し、再びヘリウムガスを常圧まで注入して１００
０℃まで昇温して３時間保持し、炉内で徐冷した。この
後、この熱処理によって得られたガラス体は、無色透明
であり、レーザー光をあてても散乱のない光透過性に優
れたガラスであった。The dried gel of this porous body was heat-treated to 250 ° C. while continuously flowing oxygen gas at room temperature, and then the furnace was evacuated and the pressure was reduced to 10 mmHg and kept for 1 hour. Oxygen gas was injected again, the pressure was maintained at normal pressure for 1 hour, the gas was evacuated to 1 mmHg, and the pressure was maintained for 1 hour. After this,
Inject oxygen gas to atmospheric pressure and hold at 600 ℃ for 3 hours,
It was evacuated, depressurized to 10 mmHg, and held for 1 hour. In addition, oxygen gas was injected up to atmospheric pressure and kept for 1 hour.
The pressure was reduced to mHg and kept for 1 hour. After that, the oxygen gas was replaced with helium gas to return to normal pressure, the temperature was raised to 900 ° C., the temperature was maintained for 3 hours, and then exhausted at 850 ° C. to 10 mm.
Depressurize to Hg and inject helium gas to atmospheric pressure to reach 90
Hold at 0 ° C. for 3 hours. After that, the gas is evacuated and the pressure is reduced to 1 mmHg, and then helium gas is again injected to the normal pressure to 100
The temperature was raised to 0 ° C., held for 3 hours, and then gradually cooled in the furnace. After that, the glass body obtained by this heat treatment was colorless and transparent, and was a glass having excellent light transmittance without scattering even when irradiated with a laser beam.

【００２５】[0025]

【発明の効果】以上のように、本発明のガラス体の製造
方法によれば、ガラス体中に気泡が存在しない、光透過
性に優れたガラス体を短時間に製造することが可能であ
る。As described above, according to the method for producing a glass body of the present invention, it is possible to produce a glass body which has no bubbles in the glass body and is excellent in light transmittance in a short time. .

【図面の簡単な説明】[Brief description of drawings]

【図１】排気を繰り返す工程において、熱処理温度と炉
内の圧力との関係を示すグラフである。FIG. 1 is a graph showing a relationship between a heat treatment temperature and a pressure in a furnace in a process of repeating exhaust.

【図２】排気を繰り返す工程において、減圧度を排気す
る度に大きくする場合の熱処理温度と炉内の圧力との関
係を示すグラフである。FIG. 2 is a graph showing the relationship between the heat treatment temperature and the pressure in the furnace when the degree of pressure reduction is increased each time the gas is exhausted in the process of repeating the exhaust.

【図３】減圧過程において、炉内を急激に排気してから
熱処理を行う場合の熱処理時間と炉内の圧力との関係を
示すグラフである。FIG. 3 is a graph showing the relationship between the heat treatment time and the pressure in the furnace when the heat treatment is performed after the furnace is rapidly evacuated in the depressurization process.

【図４】減圧過程において、炉内を徐々に排気しながら
熱処理を行う場合の熱処理時間と炉内の圧力との関係を
示すグラフである。FIG. 4 is a graph showing the relationship between the heat treatment time and the pressure in the furnace when the heat treatment is performed while gradually exhausting the furnace in the depressurization process.

─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───

【手続補正書】[Procedure amendment]

【提出日】平成５年５月１４日[Submission date] May 14, 1993

【手続補正１】[Procedure Amendment 1]

【補正対象書類名】明細書[Document name to be amended] Statement

【補正対象項目名】００１４[Correction target item name] 0014

【補正方法】変更[Correction method] Change

【補正内容】[Correction content]

【００１４】従来、常圧でへリウムガスを流し続けるこ
とによって炉内にある水分を含んだヘリウムガスを排気
することは膨大な時間がかかり、迅速に炉内の水分を除
去することは不可能であった。しかし、本発明の方法、
つまりヘリウムガスで熱処理を行った後、炉内の減圧排
気を繰り返す工程（一度ヘリウムガス雰囲気で焼結をし
ておいて、その後炉内を減圧して多孔質体から発生した
水分を含んだヘリウムガスを排気しておき、あらたにヘ
リウムガスを加えて焼成する工程）を行うと、焼成時に
おけるヘリウムガスが常に水分を含まない状態を効率よ
く保つことが可能である。このため、多孔質体に水分が
気孔や表面に再吸着したり、Ｓｉ−Ｏ−Ｓｉの網目結合
が切断されて再びシラノール基が再生成することを抑制
することができる。さらに、炉内を減圧した雰囲気中で
多孔質体を加熱するので、水の蒸気圧を低下させ、多孔
質体の細孔中に吸着した水分の除去をより効果的に行う
ことが可能である。以上のことから、減圧排気の後、ヘ
リウムガスを注入して熱処理する工程を繰り返すことに
より、より有効な水分の除去ができ、ひいては多孔質体
をガラス化する際に発生する気泡の発生を防止すること
ができる。Conventionally, it takes an enormous amount of time to exhaust the helium gas containing moisture in the furnace by continuously flowing the helium gas at normal pressure, and it is impossible to quickly remove the moisture in the furnace. there were. However, the method of the invention,
In other words, after heat-treating with helium gas, the step of repeatedly depressurizing and exhausting the inside of the furnace (sintering once in a helium gas atmosphere, then depressurizing the inside of the furnace and helium containing water generated from the porous body) It is possible to efficiently keep the state in which the helium gas does not always contain water at the time of firing by performing the step of firing the gas by exhausting the gas and newly adding helium gas. Therefore, it is possible to prevent moisture from being re-adsorbed to the pores and the surface of the porous body, and the re-generation of silanol groups due to the breaking of the Si—O—Si network bond. Furthermore, since the porous body is heated in a reduced pressure atmosphere in the furnace, it is possible to reduce the vapor pressure of water and more effectively remove the water adsorbed in the pores of the porous body. . From the above, by repeating the process of injecting helium gas and heat-treating after depressurization exhaust, more effective water removal can be performed, and eventually the generation of bubbles when vitrifying a porous body is prevented. can do.

【手続補正２】[Procedure Amendment 2]

【補正対象書類名】明細書[Document name to be amended] Statement

【補正対象項目名】００１８[Correction target item name] 0018

【補正方法】変更[Correction method] Change

【補正内容】[Correction content]

【００１８】[0018]

【実施例１】シリカ原料にＳｉ（ＯＣ２Ｈ５）４ を使用
した。Ｓｉ（ＯＣ２Ｈ５）４１０．６ｇにエタノール１
８．４ｇを加えて１時間撹拌した後、水１０ｍｌと１規
定塩酸３ｍｌとを混合した溶液を滴下してゾルを得た。
このゾルを直径１８ｍｍのポリプロピレンチューブ容器
にキャスティングして、５０℃の恒温槽で放置し、ゲル
化させた後、さらに熟成し、乾燥して多孔質の乾燥ゲル
を得た。Example 1 Si (OC 2 H 5 ) 4 was used as a silica raw material. 10.6 g of Si (OC 2 H 5 ) 4 and 1 part of ethanol
After adding 8.4 g and stirring for 1 hour, a solution obtained by mixing 10 ml of water and 3 ml of 1N hydrochloric acid was added dropwise to obtain a sol.
This sol was cast in a polypropylene tube container having a diameter of 18 mm, left in a constant temperature bath at 50 ° C. for gelation, further aged, and dried to obtain a porous dry gel.

Claims (3)

【特許請求の範囲】[Claims] 【請求項１】 多孔質体を加熱処理することによりガラ
ス体を作製するガラス体の製造方法において、多孔質体
を加熱処理する際に、炉内部の気体を排気して減圧した
後、炉内部に同種の気体を注入して熱処理する工程を有
することを特徴とするガラス体の製造方法。1. In a method for producing a glass body, in which a glass body is produced by heat-treating a porous body, when the heat treatment is performed on the porous body, the gas inside the furnace is exhausted to reduce the pressure, and then the inside of the furnace is depressurized. A method for manufacturing a glass body, comprising the step of injecting the same kind of gas into the glass and heat-treating the same. 【請求項２】 炉内部の気体を排気して減圧した後、再
び炉内部に気体を注入して熱処理する前記工程を複数回
繰り返すことを特徴とする請求項１記載のガラス体の製
造方法。2. The method for manufacturing a glass body according to claim 1, wherein the step of exhausting the gas in the furnace to reduce the pressure and then again injecting the gas into the furnace and performing the heat treatment is repeated a plurality of times. 【請求項３】 ２回目以降の前記熱処理工程における減
圧は、前回よりさらに減圧することを特徴とする請求項
２記載のガラス体の製造方法。3. The method for producing a glass body according to claim 2, wherein the pressure reduction in the second and subsequent heat treatment steps is further reduced compared to the previous time.
JP8667393A 1993-03-22 1993-03-22 Production of glass body Withdrawn JPH06271321A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP8667393A JPH06271321A (en) 1993-03-22 1993-03-22 Production of glass body

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8667393A JPH06271321A (en) 1993-03-22 1993-03-22 Production of glass body

Publications (1)

Publication Number Publication Date
JPH06271321A true JPH06271321A (en) 1994-09-27

Family

ID=13893556

Family Applications (1)

Application Number Title Priority Date Filing Date
JP8667393A Withdrawn JPH06271321A (en) 1993-03-22 1993-03-22 Production of glass body

Country Status (1)

Country Link
JP (1) JPH06271321A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6297058B1 (en) * 1999-01-14 2001-10-02 Agere Systems Optoelectronics Guardian Corp. Process for determining impurities in refractory materials
DE3902313C3 (en) * 1988-01-27 2003-07-24 Sony Corp Analog / digital converter

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3902313C3 (en) * 1988-01-27 2003-07-24 Sony Corp Analog / digital converter
US6297058B1 (en) * 1999-01-14 2001-10-02 Agere Systems Optoelectronics Guardian Corp. Process for determining impurities in refractory materials

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