JPH01138139A - Production of silica glass - Google Patents
Production of silica glassInfo
- Publication number
- JPH01138139A JPH01138139A JP29445587A JP29445587A JPH01138139A JP H01138139 A JPH01138139 A JP H01138139A JP 29445587 A JP29445587 A JP 29445587A JP 29445587 A JP29445587 A JP 29445587A JP H01138139 A JPH01138139 A JP H01138139A
- Authority
- JP
- Japan
- Prior art keywords
- gel
- silica glass
- silica
- polymethacrylamide
- cracks
- 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
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims abstract description 27
- 238000004519 manufacturing process Methods 0.000 title claims description 12
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229910052710 silicon Inorganic materials 0.000 claims description 8
- 239000010703 silicon Substances 0.000 claims description 8
- -1 silicon alkoxide Chemical class 0.000 claims description 8
- 239000000499 gel Substances 0.000 abstract description 20
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 abstract description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 15
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 abstract description 10
- 238000001035 drying Methods 0.000 abstract description 5
- 125000000217 alkyl group Chemical group 0.000 abstract description 4
- 230000007062 hydrolysis Effects 0.000 abstract description 4
- 238000006460 hydrolysis reaction Methods 0.000 abstract description 4
- 238000005245 sintering Methods 0.000 abstract description 4
- 150000004703 alkoxides Chemical class 0.000 abstract description 3
- 239000000741 silica gel Substances 0.000 abstract description 2
- 229910002027 silica gel Inorganic materials 0.000 abstract description 2
- 229920001296 polysiloxane Polymers 0.000 abstract 2
- 235000019441 ethanol Nutrition 0.000 description 9
- 238000000034 method Methods 0.000 description 4
- OEYIOHPDSNJKLS-UHFFFAOYSA-N choline Chemical compound C[N+](C)(C)CCO OEYIOHPDSNJKLS-UHFFFAOYSA-N 0.000 description 3
- 229960001231 choline Drugs 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000001879 gelation Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000011259 mixed solution Substances 0.000 description 3
- 238000003980 solgel method Methods 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 229920002125 Sokalan® Polymers 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000004584 polyacrylic acid Substances 0.000 description 2
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 description 1
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 1
- NIPNSKYNPDTRPC-UHFFFAOYSA-N N-[2-oxo-2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)ethyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 NIPNSKYNPDTRPC-UHFFFAOYSA-N 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000003349 gelling agent Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- CRNJBCMSTRNIOX-UHFFFAOYSA-N methanolate silicon(4+) Chemical compound [Si+4].[O-]C.[O-]C.[O-]C.[O-]C CRNJBCMSTRNIOX-UHFFFAOYSA-N 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 239000005049 silicon tetrachloride Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
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
- C03C1/00—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
- C03C1/006—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels to produce glass through wet route
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Glass Melting And Manufacturing (AREA)
- Silicon Compounds (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は光学用、半導体工業用、電子工業用、理化学用
等に使用されるシリカガラスを製造する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention produces silica glass used for optics, semiconductor industry, electronic industry, physics and chemistry, etc.
（従来の技術）
シリカガラスは耐熱性、耐食性および光学的性質に優れ
ていることから、半導体 製造に欠かせない重要な材料
であり、さらには光ファイバやＩＣ製造用フォトマスク
基板、ＴＦＴｉ板などに使用され、その用途はますます
拡大されている。(Prior art) Silica glass has excellent heat resistance, corrosion resistance, and optical properties, so it is an important material indispensable for semiconductor manufacturing, and is also used in optical fibers, photomask substrates for IC manufacturing, TFTi plates, etc. It has been used for many years, and its applications are being expanded more and more.
従来のシリカガラスの製造法には、天然石英を電気炉ま
たは酸水素炎により溶解する方法、あるいは四塩化ケイ
素を酸水素炎又はプラズマ炎中で高温酸化し溶解する方
法があるが、いずれの方法も製造工程に２０００℃ある
いはそれ以上の高温を必要とするため大量のエネルギー
を消費し、また製造時にそのような高温に耐える材料が
必要であり、また高純度のものが得にくいなど経済的２
品質的にいくつかの問題点をもっている。Conventional methods for manufacturing silica glass include melting natural quartz in an electric furnace or oxyhydrogen flame, or oxidizing and melting silicon tetrachloride at high temperature in an oxyhydrogen flame or plasma flame. However, the manufacturing process requires high temperatures of 2000°C or higher, which consumes a large amount of energy, and materials that can withstand such high temperatures are required during manufacturing, and it is difficult to obtain high-purity materials, making it an economical problem.
There are some quality issues.
これに対し、近年ゾル−ゲル法と呼ばれるシリカガラス
を低温で合成する方法が注目されている。その概要を簡
単に述べる。On the other hand, in recent years, a method of synthesizing silica glass at low temperature called the sol-gel method has been attracting attention. The outline will be briefly described below.
一般式Ｓ １（ＯＲ） ａ （Ｒ：アルキル基）で表わ
されるシリコンアルキシド（本発明に於いては、その重
縮合物を含む）１例えば（Ｒ○）、Ｓｉ ・ （ＯＳ
ｉ （ＯＲ）２）−・Ｏ３ｉ（ＯＲ）３． （ｎ ＝
Ｏ４０，Ｒ：アルキル基）に水（アルカリまたは酸で
ｐ）（を調整してもよい）を加え、加水分解し、シリカ
ヒドロシル（本発明に於いてはシリカゾルという）とす
る、この時、シリコンアルコキシドと水が均一な系とな
る様、一般には溶媒として適当なアルコールが添加され
ている。このシリカゾルを静置、昇温、ゲル化剤の添加
等によってゲル化させる。その後ゲルを蒸発乾燥するこ
とによりシリカ乾燥ゲルとする。この乾燥ゲルを適当な
雰囲気中で焼結することによりシリカガラスを得る。Silicon alkoxide (including its polycondensate in the present invention) represented by the general formula S 1 (OR) a (R: alkyl group) 1 For example, (R○), Si ・ (OS
i (OR)2)-・O3i(OR)3. (n =
O40, R: alkyl group) is added with water (p may be adjusted with an alkali or acid) and hydrolyzed to form silica hydrosyl (referred to as silica sol in the present invention), at this time, An appropriate alcohol is generally added as a solvent so that the silicon alkoxide and water form a homogeneous system. This silica sol is gelled by standing still, increasing the temperature, adding a gelling agent, etc. Thereafter, the gel is evaporated to dryness to obtain a dry silica gel. Silica glass is obtained by sintering this dried gel in a suitable atmosphere.
（発明が解決しようとする問題点）
しかし、ゾル−ゲル法によるシリカガラスの製造にはま
だ未解決の問題が残されている。(Problems to be Solved by the Invention) However, there are still unresolved problems in the production of silica glass by the sol-gel method.
特にゲルを乾燥していく過程でゲルにクランクや割れが
発生し易く、クランクや割れのないモノリシックな大形
の乾燥ゲルを歩留り良く製造することが困難となること
である。In particular, during the process of drying the gel, cracks and cracks are likely to occur in the gel, making it difficult to produce a monolithic large-sized dried gel without any cracks or cracks with a good yield.
本発明はクラックや割れの発生することのないシリカガ
ラスの製造法を提供するものである。The present invention provides a method for producing silica glass that does not cause cracks or breaks.
（問題点を解決するための手段）
本発明は、ゾル−ゲル法によるシリカガラスの製造法に
於て、ゾル調整時に、ポリメタクリルアミドを添加する
ことを特徴とするものである。(Means for Solving the Problems) The present invention is characterized in that polymethacrylamide is added during sol preparation in a silica glass manufacturing method using a sol-gel method.
本発明において、シリコンアルコキシドのアルキル基に
ついて、特に制限はないが、加水分解のし易さ、ゲル化
時間の点から、メチル基、エチル基、プロピル基、ブチ
ル基を有するシリコンアルコキシドを使用することが好
ましい。シリコンアルコキシドに水又は水とアルコール
の混合溶液を加えて加水分解してシリカゾルを生成させ
る際、水、アルコール、又は水とアルコールの混合溶液
にあらかじめポリメタクリルアミドを添加、均一に溶解
させておく。In the present invention, there are no particular restrictions on the alkyl group of silicon alkoxide, but from the viewpoint of ease of hydrolysis and gelation time, silicon alkoxide having a methyl group, ethyl group, propyl group, or butyl group is used. is preferred. When adding water or a mixed solution of water and alcohol to silicon alkoxide and hydrolyzing it to generate silica sol, polymethacrylamide is added in advance to the water, alcohol, or a mixed solution of water and alcohol, and is uniformly dissolved.
添加するポリメタクリルアミドの分子量は。What is the molecular weight of the polymethacrylamide to be added?
ポリアクリル酸を水、アルコール、又は水とアルコール
の混合溶液にあらかじめ添加、均一に溶解させておく点
等を考慮して選定される。The polyacrylic acid is selected in consideration of the fact that polyacrylic acid is added in advance to water, alcohol, or a mixed solution of water and alcohol so that it is uniformly dissolved.
添加するポリメタクリルアミドの量は用いるシリコンア
ルコキシドの種類等、及び加水分解速度によって適宜調
整する。The amount of polymethacrylamide to be added is appropriately adjusted depending on the type of silicon alkoxide used and the rate of hydrolysis.
水と共に加える触媒は、塩基、酸等特に制限しないが、
ゲル化時間、また得られる乾燥ゲルの焼結のし易すさの
点から塩基の方が好ましい結果が得られる。水と共に加
えるアルコールについては特に制限しないが、水、アル
コキシドの両者に対する溶解性の点より。The catalyst added with water is not particularly limited, such as bases and acids, but
From the viewpoint of gelation time and ease of sintering of the resulting dry gel, a base gives more preferable results. There are no particular restrictions on the alcohol added together with water, but from the viewpoint of solubility in both water and alkoxide.
メチルアルコール、エチルアルコール、１−プロピルア
ルコール、２−プロピルアルコール等のアルコール類を
使用するのが好ましい。Preferably, alcohols such as methyl alcohol, ethyl alcohol, 1-propyl alcohol, 2-propyl alcohol are used.
シリカガラスは、上記のようにして調整したシリカゾル
をシャーレ等の容器に移し、室温〜７０℃に保って、ゲ
ル化し２次いで室温以上の温度で数週間乾燥して、乾燥
ゲルとし。Silica glass is obtained by transferring the silica sol prepared as described above to a container such as a petri dish, keeping it at room temperature to 70°C to gel it, and then drying it at a temperature above room temperature for several weeks to form a dry gel.
更に公知の方法１例えば、空気中で１０００〜１４００
℃に昇温して焼結することにより得られる。Further known method 1, for example, 1000 to 1400 in air
Obtained by heating to ℃ and sintering.
（作用）
ポリメタクリルアミドの添加効果の原因については、詳
細は不明であるが、ゾル中でのシリカ微粒子の生成の制
御、ゲル中でのこれらのシリカ微粒子間の結合、乾燥過
程でゲル中に発生する応力の緩和等に寄与し、ゲルの大
形化が可能となったものと考えられる。(Effect) Although the details of the causes of the effect of adding polymethacrylamide are unknown, there is control of the formation of silica particles in the sol, bonding between these silica particles in the gel, and formation of silica particles in the gel during the drying process. It is thought that this contributed to alleviation of the stress generated and made it possible to increase the size of the gel.
実施例 １
３モルのメチルアルコールと３モルの水と０．０００５
モルのコリンを混合し、これに７．６ｇのポリメタクリ
ルアミドを添加し溶解させた。得られた溶液を１モルの
シリコンメトキシド（Ｓｉ（ＯＣＨｓ）ａ）にゆっくり
と加え、さらに充分混合しシリカゾルを得た。これを直
径１５０ｍｗ＋のテフロンでコーティングしたガラス製
シャーレに入れ、アルミ箔で密封し。Example 1 3 moles of methyl alcohol, 3 moles of water and 0.0005
Mol of choline was mixed and 7.6 g of polymethacrylamide was added and dissolved. The obtained solution was slowly added to 1 mol of silicon methoxide (Si(OCHs)a) and mixed thoroughly to obtain a silica sol. This was placed in a Teflon-coated glass petri dish with a diameter of 150 mw+ and sealed with aluminum foil.
室温でゲル化した。その後、Ｈに孔を開け。It gelled at room temperature. Then, drill a hole in H.
５０℃の恒温槽中で２週間乾燥し、その後１２０℃の恒
温槽に移して１日乾燥して、直径約１２０ｍｍの乾燥ゲ
ルを得た。こうして得られた乾燥ゲルのかさ密度は約０
．６ｇ／ｃｄであり、クランクや割れは全くなかった。It was dried for two weeks in a constant temperature bath at 50°C, and then transferred to a constant temperature bath at 120°C and dried for one day to obtain a dried gel with a diameter of about 120 mm. The bulk density of the dry gel thus obtained is approximately 0.
．． 6 g/cd, and there were no cranks or cracks.
得られたゲルを空気中１２００℃まで加熱焼結したとこ
ろ直径約８０１．厚さ５ｍｍのクランクや割れのない透
明なシリカガラスが得られた。このシリカガラスは分析
の結果、そのシリカガラスと一致した。When the resulting gel was heated and sintered in air to 1200°C, it had a diameter of approximately 801mm. A transparent silica glass with a thickness of 5 mm and no cracks or cracks was obtained. As a result of analysis, this silica glass matched that of the silica glass.
実施例 ２
ポリメタクリルアミド３．０ｇを３モルのメチルアルコ
ール、３モルの水、０．０００５モルのコリンとを混合
した。以下実施例１と同様の操作を行って乾燥ゲルを得
た。得られた乾燥ゲルにはクランクや割れは全くなかっ
た。Example 2 3.0 g of polymethacrylamide was mixed with 3 moles of methyl alcohol, 3 moles of water, and 0.0005 moles of choline. Thereafter, the same operation as in Example 1 was performed to obtain a dry gel. The dried gel obtained had no cracks or cracks.
実施例 ３
ポリメタクリルアミド１５．２ ｇを３モルのメチルア
ルコール、３モルの水、ｏ、ｏｏｏｓモルのコリンとを
混合した。以下実施例１と同様の操作を行って乾燥ゲル
を得た。得られた乾燥ゲルにはクランクや割れは全くな
かった。Example 3 15.2 g of polymethacrylamide were mixed with 3 moles of methyl alcohol, 3 moles of water, and o,oos moles of choline. Thereafter, the same operation as in Example 1 was performed to obtain a dry gel. The dried gel obtained had no cracks or cracks.
（発明の効果）
本発明によれば、クランクや割れのない大形のシリカガ
ラスをゾルアール法により容易に製造可能となる。その
大きさは基本的には制約がなく、形状も板状、棒状、管
状等のいずれでも製造できる。(Effects of the Invention) According to the present invention, large-sized silica glass without cranks or cracks can be easily manufactured by the Zorar method. There are basically no restrictions on its size, and it can be manufactured in any shape such as a plate, rod, or tube.
また１本発明によればシリカガラスは従来より安価に製
造できるため、従来から使用されてきたＩＣ製造用フォ
トマスク基材等の分野はもちろん、液晶表示用基材等に
も応用が拡大できる。Furthermore, according to the present invention, silica glass can be manufactured at a lower cost than before, so it can be applied not only to fields such as photomask substrates for IC manufacturing, which have been conventionally used, but also to substrates for liquid crystal displays, etc.
Claims (1)
し、次いで焼結するシリカガラスの製造法に於て、シリ
コンアルキシドを加水分解してシリカゾルとする段階で
、ポリメタクリルアミドを添加することを特徴とするシ
リカガラスの製造法。[Scope of Claims] 1. In a method for producing silica glass in which silicon alkoxide is hydrolyzed to form silica sol, this is gelled, dried to form a dry gel, and then sintered, silicon alkoxide is hydrolyzed. A method for producing silica glass, characterized in that polymethacrylamide is added at the step of preparing a silica sol.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29445587A JPH01138139A (en) | 1987-11-20 | 1987-11-20 | Production of silica glass |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29445587A JPH01138139A (en) | 1987-11-20 | 1987-11-20 | Production of silica glass |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01138139A true JPH01138139A (en) | 1989-05-31 |
Family
ID=17808004
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29445587A Pending JPH01138139A (en) | 1987-11-20 | 1987-11-20 | Production of silica glass |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01138139A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0345519A (en) * | 1989-07-13 | 1991-02-27 | Toyo Ink Mfg Co Ltd | Production of glass from liquid phase |
| EP0583943A3 (en) * | 1992-08-14 | 1994-08-17 | At & T Corp | Manufacture of a vitreous silica product by a sol-gel process |
-
1987
- 1987-11-20 JP JP29445587A patent/JPH01138139A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0345519A (en) * | 1989-07-13 | 1991-02-27 | Toyo Ink Mfg Co Ltd | Production of glass from liquid phase |
| EP0583943A3 (en) * | 1992-08-14 | 1994-08-17 | At & T Corp | Manufacture of a vitreous silica product by a sol-gel process |
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| JPH03137029A (en) | Production of silica glass | |
| JPH0259446A (en) | Production of silica glass | |
| JPH01119523A (en) | Production of silica glass | |
| JPH02248332A (en) | Production of silica glass | |
| JPH01119527A (en) | Production of silica glass | |
| JPH01119525A (en) | Production of silica glass | |
| JPH0259442A (en) | Production of silica glass | |
| JPH0259438A (en) | Production of silica glass |