JPS63195137A - Removal of striae of quartz glass - Google Patents
Removal of striae of quartz glassInfo
- Publication number
- JPS63195137A JPS63195137A JP2470287A JP2470287A JPS63195137A JP S63195137 A JPS63195137 A JP S63195137A JP 2470287 A JP2470287 A JP 2470287A JP 2470287 A JP2470287 A JP 2470287A JP S63195137 A JPS63195137 A JP S63195137A
- Authority
- JP
- Japan
- Prior art keywords
- quartz glass
- striae
- powder
- pressure
- inert gas
- 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
- 206010040925 Skin striae Diseases 0.000 title claims abstract description 46
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims abstract description 43
- 239000000843 powder Substances 0.000 claims abstract description 19
- 239000002245 particle Substances 0.000 claims abstract description 9
- 239000011261 inert gas Substances 0.000 claims abstract description 6
- 238000010438 heat treatment Methods 0.000 claims abstract description 5
- 238000000034 method Methods 0.000 claims description 21
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 4
- 239000007789 gas Substances 0.000 claims description 4
- 229910052757 nitrogen Inorganic materials 0.000 claims description 2
- 238000003825 pressing Methods 0.000 claims description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 10
- 229910052799 carbon Inorganic materials 0.000 abstract description 9
- 230000006835 compression Effects 0.000 abstract 1
- 238000007906 compression Methods 0.000 abstract 1
- 239000011521 glass Substances 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 5
- 230000003287 optical effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000011156 evaluation Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000005350 fused silica glass Substances 0.000 description 2
- 238000007731 hot pressing Methods 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- -1 5IO2 Chemical compound 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
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
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/20—Doped silica-based glasses doped with non-metals other than boron or fluorine
- C03B2201/24—Doped silica-based glasses doped with non-metals other than boron or fluorine doped with nitrogen, e.g. silicon oxy-nitride glasses
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は光デバイス、光通信用ファイバ、光学用部品（
窓、レンズプリズム、紫外線用素子等）。[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to optical devices, optical communication fibers, optical components (
windows, lens prisms, ultraviolet ray elements, etc.).
マスク用基板等に使用される石英ガラスのうち脈理を含
存する石英ガラス中の脈理の除去方法に関するものであ
る。The present invention relates to a method for removing striae in quartz glass containing striae, which is used for mask substrates and the like.
［従来の技術］
特開昭５８−１２９８２１号公報に、石英ガラスを、１
気圧ないし真空下に１７００℃以上に加熱し、ついで１
１００〜１３００℃に急冷することによる成形方法が提
案されているが、これにはこの方法によればあわせて脈
理も除かれる旨記載されている。[Prior art] Japanese Patent Application Laid-Open No. 58-129821 discloses that quartz glass is
Heating to 1700℃ or higher under atmospheric pressure or vacuum, then 1
A molding method using rapid cooling to 100 to 1300° C. has been proposed, and it is stated that striae can also be removed by this method.
［発明が解決しようとする問題点］
上記の方法のように成形すなわち変形をさせつつ処理す
る場合は、１気圧ないし真空下でも脈理は除かれるかも
しれないが、本発明者らは、そのような変形をさせずに
低圧下で加熱しても、脈理を十分に除くことはできない
ことを見出した。すなわち、本発明は石英ガラスの初期
の形状を保ったまま、より確実に容易に脈理を除去する
方法を提供することを目的とするものである。[Problems to be Solved by the Invention] When processing is performed while forming or deforming as in the above method, striae may be removed even under 1 atm or vacuum, but the present inventors have found that It has been found that striae cannot be sufficiently removed even if heated under low pressure without causing such deformation. That is, an object of the present invention is to provide a method for more reliably and easily removing striae while maintaining the initial shape of quartz glass.
［問題点を解決するための手段および作用］本発明の方
法は、脈理を含む石英ガラスを不活性ガス雰囲気内で軟
化させ同時に圧力を加え、粘性をもたせた石英ガラスに
撹拌効果をもたせることで、脈理除去を行うものである
。[Means and effects for solving the problem] The method of the present invention involves softening quartz glass containing striae in an inert gas atmosphere and simultaneously applying pressure to impart a stirring effect to the viscous quartz glass. It is used to remove striae.
本発明に適用される石英ガラスは、溶融石英法。The fused silica method is used for the fused silica glass applied to the present invention.
合成石英法その他いかなる方法で作製したものでも良い
。形状、大きさ等にも制限はないが操作性の点で２０Ｃ
Ｉ１１程度のあらかじめ、はぼ製品寸法にされている物
が好ましい。この石英ガラスを不活性ガス雰囲気内で高
温高圧で処理して脈理を除去する。It may be manufactured by any method other than the synthetic quartz method. There are no restrictions on shape or size, but 20C is recommended in terms of operability.
It is preferable to use a material that is pre-sized to the size of the product, approximately I11. This quartz glass is treated at high temperature and pressure in an inert gas atmosphere to remove striae.
脈理の除去の雑品は、石英ガラスの大きさおよびその強
さに左右されるが、処理温度を１５００℃以上、処理圧
力を１０ ＭＰａ以上とすることにより、比較的短時間
で脈理が除かれる。１５００℃未満あるいはｔｏ ＭＰ
ａ未満では石英ガラスの初期形状を保ったまま脈理を拡
散することができない。Miscellaneous products for removing striae depend on the size and strength of the quartz glass, but striae can be removed in a relatively short time by setting the processing temperature to 1500°C or higher and the processing pressure to 10 MPa or higher. It will be destroyed. Less than 1500℃ or to MP
If it is less than a, striae cannot be diffused while maintaining the initial shape of the quartz glass.
また１５００℃以上、１０ＭＰａ以上に保持した後、圧
力を１０ＭＰａ未満に下げ、再び１０ＭＰａ以上に上げ
るという操作を繰り返すことによっても、よりよく脈理
を除くことができる。Furthermore, striae can be better removed by repeating the operation of maintaining the pressure at 1500° C. or higher and 10 MPa or higher, lowering the pressure to lower than 10 MPa, and increasing the pressure to 10 MPa or higher again.
雰囲気としては、高温、高圧にするためアルゴンガスを
使用するのが一般的であるが、他の希ガスもしくは窒素
またはその混合ガスでもよい。Argon gas is generally used as the atmosphere to achieve high temperature and high pressure, but other rare gases, nitrogen, or a mixture thereof may also be used.
さらに、石英ガラスの周囲に石英ガラスに対して不活性
な粉末、たとえば５ＩＯ２，Ｃ、ＳｉＣ、安定化ｚ「０
２等の粉末を充填することにより、石英ガラスの初期形
状をより完全に保ったまま短時間で脈理を除去すること
ができる。ここで使用する粉末の粒度は５０μｍ〜５ｍ
ｍが好ましい。５ｆｆｌＩ１１を越えると流動性のある
石英ガラスを脈理除去処理前の形状に保持する効果に乏
しく、５０μｍ未満では粉末が焼結しすぎて強固になり
石英ガラスの取り出しが面倒になるためである。これら
の粒度５゜μｍ〜５ｍａ＋の粉末では完全には焼結しな
いので、石英ガラスのとりたしが容易である。Further, around the quartz glass, powder inert to the quartz glass, such as 5IO2,C, SiC, stabilizing z "0
By filling powder such as No. 2, striae can be removed in a short time while maintaining the initial shape of the quartz glass more completely. The particle size of the powder used here is 50 μm to 5 m
m is preferred. This is because if it exceeds 5fflI11, the effect of holding the fluid quartz glass in the shape before the striae removal treatment is poor, and if it is less than 50 μm, the powder will be too sintered and become strong, making it difficult to take out the quartz glass. Since these powders with a particle size of 5 μm to 5 ma+ are not completely sintered, it is easy to remove the quartz glass.
使用する粉末の粒度により温度、圧力、処理時間は変っ
てくる。温度、圧力、処理時間は、粒度が小さい場合、
比較的低く、短くしなければならない。充填した粉末が
焼結しすぎて強固になるのを防ぐためである。一方、粒
度が大きい場合は、温度、圧力、処理時間は、高く、長
くすることができる。Temperature, pressure, and processing time vary depending on the particle size of the powder used. Temperature, pressure, and processing time should be adjusted when the particle size is small.
Must be relatively low and short. This is to prevent the filled powder from becoming too strong due to sintering. On the other hand, if the particle size is large, the temperature, pressure and processing time can be higher and longer.
以上のような脈理の除去を行うための簡便な装置として
ホットプレスまたはＨＩＰ（熱間静水圧プレス）が適し
ている。ホットプレスの場合も、粉末を充填しているこ
とにより石英ガラスは擬ＨＩＰ状態におかれ、ＨＩＰと
ほぼ同様な効果を生ずる。A hot press or HIP (hot isostatic press) is suitable as a simple device for removing striae as described above. In the case of hot pressing, the quartz glass is placed in a quasi-HIP state by being filled with powder, producing almost the same effect as HIP.
１７００℃以上の高温で脈理除去を行う場合は充填する
粉末の焼結はかなり進行するため、ホットプレスよりＨ
ＩＰで行うほうが好ましい。ＨＩＰ装置で実施した場合
、充填する粉末はほとんど焼結せずに残るため、石英ガ
ラスの取り出しはホットプレスに比べ非常に容易である
。When striae removal is performed at a high temperature of 1700°C or higher, sintering of the filling powder progresses considerably, so
It is preferable to use IP. When carried out using a HIP device, the powder to be filled remains almost unsintered, so it is much easier to take out the quartz glass than with hot pressing.
本発明の脈理の除去方法によると、石英ガラス中に含有
される脈理は石英ガラスおよび脈理の流動、拡散により
徐々に弱くなり最終的には完全に消滅してしまう。この
理由は明らかではないが、高温にすることにより石英ガ
ラスに流動性をもたせ、高圧にすることにより石英ガラ
ス内部に応力が生じ、これが脈理を分散させるものと思
われる。According to the striae removal method of the present invention, striae contained in quartz glass gradually weaken due to flow and diffusion of the quartz glass and striae, and eventually disappear completely. Although the reason for this is not clear, it is thought that the high temperature imparts fluidity to the quartz glass, and the high pressure generates stress inside the quartz glass, which causes the striae to disperse.
次に、本発明を図面にもとづき説明するが、−例を示す
ものであり本発明はこれになんら限定されるものではな
い。Next, the present invention will be explained based on the drawings, but the present invention is not limited to these examples.
第１図はホットプレスで脈理除去処理を行う場合の概念
図である。脈理を含有する石英ガラス１をあらかじめ製
品に近い形状に加工しておき、必要に応じて５Ｉ０２．
Ｃ、ＳｉＣ、安定化ＺｒＯ２等の粉末２の中にうめこ
んでセットする。これをカーボン押し型３とバンチ４に
より高温、高圧処理をして脈理除去を行う。FIG. 1 is a conceptual diagram when striae removal treatment is performed using a hot press. The quartz glass 1 containing striae is processed in advance into a shape close to the product, and if necessary, 5I02.
It is set by burying it in powder 2 of C, SiC, stabilized ZrO2, etc. This is subjected to high temperature and high pressure treatment using a carbon mold 3 and a bunch 4 to remove striae.
第２図は、ＨＩＰ （熱間静水圧プレス）装置を使用す
る場合の概念図である。基本的にはホットプレスと同じ
でありカーボンルツボ７内にセットする。FIG. 2 is a conceptual diagram when using a HIP (hot isostatic press) device. Basically, it is the same as a hot press and is set inside the carbon crucible 7.
以上の様な方法により容易に脈理除去を行うことが出来
る。Striae can be easily removed by the method described above.
［実施例］
次に、本発明を実施例により更に詳細に説明するが、−
例を示すものであり、本発明はこれらの実施例になんら
限定されるものではない。[Example] Next, the present invention will be explained in more detail with reference to Examples.
These examples are shown, and the present invention is not limited to these examples in any way.
（実施例１．２、比較例１〜６）
直径７０ｍｍ５高さ７０ｍｍ、歪計で強く確認された脈
理を含む石英ガラスを第１図に示す様にホットプレス用
カーボン押し型にセットした。この時、充填粉末はＳＩ
Ｃ粉末（粒度５０〜１００μｍ）を使用した。昇温、降
温速度は２００℃／ｍ１ｎとして表１に示したように温
度、圧力１時間を変化させてホットプレス処理した。脈
理存無の評価前に残留応力を除去するため１０００〜１
２００℃の温度でｌｈｒ熱処理を行った。(Example 1.2, Comparative Examples 1 to 6) A piece of quartz glass having a diameter of 70 mm and a height of 70 mm and containing striae strongly confirmed by a strain meter was set in a hot press carbon mold as shown in FIG. At this time, the filling powder is SI
C powder (particle size 50-100 μm) was used. The hot press treatment was performed by changing the temperature and pressure for 1 hour as shown in Table 1, with the temperature increase and temperature decrease rates being 200° C./m1n. 1000 to 1 to remove residual stress before evaluating the presence or absence of striae.
An lhr heat treatment was performed at a temperature of 200°C.
結果を表１に示す。The results are shown in Table 1.
脈理を無の評価は、干渉計、歪計、艶消し白色ペイント
面のスクリーン使用のピンホール法の３方法で行った。The presence of striae was evaluated using three methods: an interferometer, a strain meter, and a pinhole method using a screen on a matte white painted surface.
脈理評価の感度は、干渉計、歪計、ピンホール法の順に
良くなるため、最終的にはピンホール法で脈理の有無を
判断した。表中、をは脈理が存在したもの、無は脈理が
存在しなかったものをあられしている。Since the sensitivity of striae evaluation increases in the order of interferometer, strain meter, and pinhole method, we ultimately determined the presence or absence of striae using the pinhole method. In the table, "" means that striae were present, and "No" means that striae did not exist.
（実施例３〜６）
一辺が２００ｍｍの立方体で歪計で強く確認された脈理
を含む石英ガラスを第２図に示す様にＨＩＰ処理用カー
ボンルツボ内にセットした。この時、充填粉末はカーボ
ン粉末（粒度０．１〜０．５ｍｍ）を使用した。昇温、
降温速度は２００℃／１ｎとして表２に示したように温
度、圧力２時間を変化させてＨＩＰ処理した。(Examples 3 to 6) A quartz glass having a cube shape of 200 mm on a side and containing striae strongly confirmed by a strain meter was set in a carbon crucible for HIP treatment as shown in FIG. 2. At this time, carbon powder (particle size 0.1 to 0.5 mm) was used as the filling powder. Temperature rising,
The HIP treatment was performed while changing the temperature and pressure for 2 hours as shown in Table 2, with a cooling rate of 200°C/1n.
評価前に残留応力を除去するため１０００〜１２００℃
の温度でｌｈｒ熱処理を行った。評価は実施例１と全く
同じ方法を使用した。1000-1200℃ to remove residual stress before evaluation
The lhr heat treatment was performed at a temperature of . The evaluation used exactly the same method as in Example 1.
結果を表２に示す。The results are shown in Table 2.
［発明の効果］
本発明によれば、
■ 初期形状を保ったまま
■ 短時間で
■ 石英ガラス中に含有する脈理を除去でき■ 光学用
石英ガラスの歩留を飛躍的に向上できる。[Effects of the Invention] According to the present invention, 1) striae contained in quartz glass can be removed in a short time while maintaining the initial shape, and 3 the yield of optical quartz glass can be dramatically improved.
第１図および第２図は、いずれも本発明の実施態様の実
施状況を示す概念図であり、第１図はホットプレス、第
２図はＨＩＰによるものである。
１．５・・・脈理を含む石英ガラス
２．６・・・粉末
３・・・・・・・・・カーボン押し型
４・・・・・・・・・カーボンバンチ
７・・・・・・・・・カーボンルツボ
特許出願人 東洋費達工業株式会社
第１図
第２図FIG. 1 and FIG. 2 are both conceptual diagrams showing the implementation status of the embodiment of the present invention, FIG. 1 is by hot press, and FIG. 2 is by HIP. 1.5... Quartz glass containing striae 2.6... Powder 3... Carbon press mold 4... Carbon bunch 7... ... Carbon crucible patent applicant Toyo Kaidat Kogyo Co., Ltd. Figure 1 Figure 2
Claims (5)
１５００℃以上に加熱し、かつ１０ＭＰａ以上に加圧す
ることを特徴とする石英ガラス中の脈理の除去方法。(1) quartz glass containing striae in an inert gas atmosphere,
A method for removing striae in quartz glass, which comprises heating to 1500° C. or higher and applying pressure to 10 MPa or higher.
ガスである特許請求の範囲第１項記載の石英ガラス中の
脈理の除去方法。(2) The method for removing striae in quartz glass according to claim 1, wherein the inert gas is a rare gas, nitrogen, or a mixed gas thereof.
粉末を充填する特許請求の範囲第１項または第２項記載
の石英ガラス中の脈理の除去方法。(3) A method for removing striae in quartz glass according to claim 1 or 2, wherein the periphery of the quartz glass is filled with powder that is inert to the quartz glass.
Ｃ、ＳＩＣ、安定化ＺｒＯ＿２である特許請求の範囲第
３項記載の石英ガラス中の脈理の除去方法。(4) The powder filled around the quartz glass is SiO_2,
The method for removing striae in quartz glass according to claim 3, which is C, SIC, stabilized ZrO_2.
ｍ〜５ｍｍである特許請求の範囲第３項または第４項記
載の石英ガラス中の脈理の除去方法。(5) The particle size of the powder packed around the quartz glass is 50μ
5. The method for removing striae in quartz glass according to claim 3 or 4, wherein the striae are from m to 5 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2470287A JPS63195137A (en) | 1987-02-06 | 1987-02-06 | Removal of striae of quartz glass |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2470287A JPS63195137A (en) | 1987-02-06 | 1987-02-06 | Removal of striae of quartz glass |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63195137A true JPS63195137A (en) | 1988-08-12 |
Family
ID=12145509
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2470287A Pending JPS63195137A (en) | 1987-02-06 | 1987-02-06 | Removal of striae of quartz glass |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63195137A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0322881A2 (en) * | 1987-12-28 | 1989-07-05 | Tosoh Corporation | Method of producing uniform silica glass block |
| JPH0274331U (en) * | 1988-11-28 | 1990-06-06 | ||
| JPH0388742A (en) * | 1989-06-09 | 1991-04-15 | Shinetsu Sekiei Kk | Synthetic silica glass optical body and production therefor |
-
1987
- 1987-02-06 JP JP2470287A patent/JPS63195137A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0322881A2 (en) * | 1987-12-28 | 1989-07-05 | Tosoh Corporation | Method of producing uniform silica glass block |
| EP0322881A3 (en) * | 1987-12-28 | 1990-09-12 | Tosoh Corporation | Method of producing uniform silica glass block |
| JPH0274331U (en) * | 1988-11-28 | 1990-06-06 | ||
| JPH0388742A (en) * | 1989-06-09 | 1991-04-15 | Shinetsu Sekiei Kk | Synthetic silica glass optical body and production therefor |
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