JPH02248332A - Production of silica glass - Google Patents
Production of silica glassInfo
- Publication number
- JPH02248332A JPH02248332A JP6997589A JP6997589A JPH02248332A JP H02248332 A JPH02248332 A JP H02248332A JP 6997589 A JP6997589 A JP 6997589A JP 6997589 A JP6997589 A JP 6997589A JP H02248332 A JPH02248332 A JP H02248332A
- Authority
- JP
- Japan
- Prior art keywords
- gel
- sol
- silica glass
- silica
- 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 28
- 238000004519 manufacturing process Methods 0.000 title claims description 11
- -1 Silicon alkoxide Chemical class 0.000 claims abstract description 11
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 11
- 239000010703 silicon Substances 0.000 claims abstract description 11
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims abstract description 10
- SZNYYWIUQFZLLT-UHFFFAOYSA-N 2-methyl-1-(2-methylpropoxy)propane Chemical compound CC(C)COCC(C)C SZNYYWIUQFZLLT-UHFFFAOYSA-N 0.000 claims description 26
- 229920002554 vinyl polymer Polymers 0.000 claims description 13
- 230000003301 hydrolyzing effect Effects 0.000 claims 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 16
- 238000003980 solgel method Methods 0.000 abstract description 5
- 230000007062 hydrolysis Effects 0.000 abstract description 3
- 238000006460 hydrolysis reaction Methods 0.000 abstract description 3
- 239000002904 solvent Substances 0.000 abstract description 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 abstract 8
- 230000001105 regulatory effect Effects 0.000 abstract 1
- 239000000499 gel Substances 0.000 description 21
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 15
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 9
- 235000019441 ethanol Nutrition 0.000 description 9
- 238000000034 method Methods 0.000 description 5
- OEYIOHPDSNJKLS-UHFFFAOYSA-N choline Chemical compound C[N+](C)(C)CCO OEYIOHPDSNJKLS-UHFFFAOYSA-N 0.000 description 4
- 229960001231 choline Drugs 0.000 description 4
- 125000000217 alkyl group Chemical group 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000011259 mixed solution Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000001879 gelation Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- CRNJBCMSTRNIOX-UHFFFAOYSA-N methanolate silicon(4+) Chemical compound [Si+4].[O-]C.[O-]C.[O-]C.[O-]C CRNJBCMSTRNIOX-UHFFFAOYSA-N 0.000 description 2
- 238000002360 preparation method Methods 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
- 239000000377 silicon dioxide Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000000758 substrate 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
- 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
- 150000004703 alkoxides Chemical class 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
- 239000010419 fine particle Substances 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
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 239000003960 organic solvent Substances 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
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- 239000005049 silicon tetrachloride Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000000126 substance 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)
- Silicon Compounds (AREA)
- Glass Melting And Manufacturing (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。[Detailed description of the invention] (Industrial application field) The present invention is applicable to optics, semiconductor industry, and electronic industry.
理化学用等に使用されるシリカガラスの製造法に関する
。This article relates to a method for producing silica glass used for physical and chemical purposes.
（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、半導体の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■Ｃ製造用フォトマスク
基板、ＴＰＴ基板などに使用され、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 for optical fibers, photomask substrates for C manufacturing, and TPT. It is used for substrates, etc., and its applications are expanding 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（いなど経済的品
質的にいくつかの問題点をもっている。Conventional methods for producing silica glass include a method in which natural quartz is melted in an electric furnace or an oxyhydrogen flame, or a method in which silicon tetrachloride is oxidized and melted at high temperature in an oxyhydrogen flame or a plasma flame. 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. There are some problems in terms of quality.
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。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.
その概要を簡単に述べる。The outline will be briefly described below.
一般式Ｓ ｉ （ＯＲ） ａ （Ｒ：アルキル基）で
表わされるシリコンアルコキシド（本発明に於いては、
その重縮合物を含む）１例えば（ＲＯ）ｓＳｉｉ（）
Ｓ ｉ （ＯＲ）ｔｌ−・ＯＳ ｉ （ＯＲ）３（ｎ
＝０〜８．Ｒ：アルキル基）に水（アルカリまたは酸で
ｐＨ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 represented by the general formula S i (OR) a (R: alkyl group) (in the present invention,
(including its polycondensate)1, for example (RO)sSii()
S i (OR)tl-・OS i (OR)3(n
=0~8. R: alkyl group) is added with water (pH may be adjusted with alkali or acid) and hydrolyzed to form silica hydrosil (referred to as silica sol in the present invention). At this time, silicon alkoxide and water An appropriate alcohol is generally added as a solvent to 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課１２１）
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。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昌＜、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。(Problem 121 to be solved by the invention) However, there are still unresolved problems in the production of silica glass by the sol-gel method. In particular, during the process of drying the gel, cracks and cracks occur in the gel, making it difficult to produce a monolithic large-sized dried gel without cracks and cracks with a good yield.
本発明はクラン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 manufacturing silica glass that does not cause cracks or cracks.
（課題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、ゾル調製時に、ポリビニルイソブチルエーテルを
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 polyvinyl isobutyl ether is added at the time of sol preparation in a method for producing silica glass by 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。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 preferable when silicon alkoxide is hydrolyzed by adding water or a mixed solution of water and alcohol to produce silica sol.
アルコール、又は水とアルコールの混合溶液にあらかじ
めポリビニルイソブチルエーテルを添加。Add polyvinyl isobutyl ether to alcohol or a mixed solution of water and alcohol in advance.
均一に溶解させておく。Let it dissolve evenly.
ポリビニルイソブチルエーテルとしては、水と相溶性の
ある有機溶媒に溶解するものが望ましい。The polyvinyl isobutyl ether is preferably one that dissolves in an organic solvent that is compatible with water.
添加するポリビニルイソブチルエーテルの分子量は、ポ
リビニルイソブチルエーテルをアルコール、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 molecular weight of the polyvinyl isobutyl ether to be added is selected in consideration of the fact that the polyvinyl isobutyl ether is added in advance to alcohol or a mixed solution of water and alcohol and is uniformly dissolved therein.
添加するポリビニルイソブチルエーテルの量は用いるシ
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 polyvinyl isobutyl ether 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、メチルアルコ
ール、エチルアルコール、ｌ−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。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. The alcohol to be added together with water is not particularly limited, but from the viewpoint of solubility in both water and alkoxide, methyl alcohol, ethyl alcohol, l-propyl alcohol,
- Preference is given to using alcohols such as propyl alcohol.
シリコンアルコキシド、溶媒、水及びポリビニルイソブ
チルエーテルは生成するゾルをできる限り均一なものと
するために、スターテなどを用いてよく混合する。また
超音波を照射してもよい。The silicon alkoxide, solvent, water, and polyvinyl isobutyl ether are thoroughly mixed using a starter or the like in order to make the resulting sol as uniform as possible. Alternatively, ultrasonic waves may be irradiated.
ゾル調製時にシリカの微粒子を加えてもよい。Fine particles of silica may be added during sol preparation.
シリカガラスは、上記のようにして調製したシリカゾル
をシャーレ等の容器に移し、室温〜７０℃に保って、ゲ
ル化し１次いで室温以上の温度で数週間乾燥して、乾燥
ゲルとし、更に公知の方法例えば、空気中で１０００〜
１４００℃に昇温して焼結することにより得られる。Silica glass is produced 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 form a gel, and then drying it at a temperature above room temperature for several weeks to form a dry gel. For example, 1000 ~
It is obtained by raising the temperature to 1400°C and sintering it.
（作用）
ポリビニルイソブチルエーテル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 effects of adding polyvinyl isobutyl ether are unknown, it is possible to control the formation of silica particles in the sol, to bond between these silica particles in the gel, and to cause the formation of silica particles in the gel during the drying process. Contributes to alleviating the stress that occurs,
It is thought that this 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にポリビニルイソブチルエー
テルを７．６ｇ充分に溶解させた後、３モし
ルの水とｏ、 ｏ ｏ ｏ ｓモルのコリンを混鈷、得
られた溶液を１モルのシリコンメトキシド（’５Ｌ（Ｏ
ＣＨｓ）ｔ）にゆっくりと加え、さらに充分混合しシリ
カゾルを得た。これをテフロンでコーティングした直径
１５０ｍｍのガラス製シャーレに入れ。Example 1 After fully dissolving 7.6 g of polyvinyl isobutyl ether in 3 moles of methyl alcohol, 3 moles of water and o, o o o s moles of choline were mixed, and the resulting solution was dissolved in 1 mole. of silicon methoxide ('5L(O
It was slowly added to CHs)t) and mixed thoroughly to obtain a silica sol. Place this in a glass petri dish with a diameter of 150 mm coated with Teflon.
ア４レミ箔で密封し、室温でゲル化した。その後。The mixture was sealed with aluminum foil and allowed to gel at room temperature. after that.
蓋に孔を開け、５０℃の恒温槽中で２週間乾燥し。A hole was made in the lid and dried for 2 weeks in a thermostatic oven at 50°C.
その後１２０℃の恒温槽に移して１日乾燥して。Then, it was transferred to a constant temperature bath at 120°C and dried for one day.
直径約１２０ｍ−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／−であり。A dried gel with a diameter of about 120 m was obtained. The bulk density of the dry gel thus obtained was approximately 0.6 g/-.
クラックや割れは全くなかった。There were no cracks or breaks at all.
得られたゲルを空気中１２００℃まで加熱焼結したとこ
ろクラックや割れのない直径約８０ｍｍ、厚さ５−―の
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、市販のシリカガラスと一致した。When the obtained gel was heated and sintered in air to 1200°C, a transparent silica glass having a diameter of about 80 mm and a thickness of 5 mm was obtained without any cracks or breaks. As a result of analysis, this silica glass matched commercially available silica glass.
実施例 ２
ポリビニルイソブチルエーテル３．０ｇを３モルのメチ
ルアルコールに充分に溶解させた後、３モルの水、ｏ、
ｏｏｏｓモルのコリンとを混合した。Example 2 After fully dissolving 3.0 g of polyvinyl isobutyl ether in 3 mol of methyl alcohol, 3 mol of water, o,
oos moles of choline were mixed.
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。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
ポリビニルイソブチルエーテル１５．２ ｇを３モルの
メチルアルコールに充分に溶解させた後、３モルの水、
０．０００５モルのコリンとを混合した。Example 3 After fully dissolving 15.2 g of polyvinyl isobutyl ether in 3 moles of methyl alcohol, 3 moles of water,
0.0005 mole of choline was mixed.
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。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 ４
ポリビニルイソブチルエーテル１０．８ｇを３モルのメ
チルアルコールに充分に溶解させた後、３モルの水とｏ
、 ｏ ｏ ｏ ｓモルのコリンを混合した。Example 4 After sufficiently dissolving 10.8 g of polyvinyl isobutyl ether in 3 mol of methyl alcohol, 3 mol of water and o
, o o o s moles of choline were mixed.
得られた溶液を１モルのシリコンメトキシドの重縮合物
（（ＣＨｚ Ｏ）ｓ Ｓｔ ・ （０−３ｉ （ＯＣ
Ｈｓ）ｚ）ｎ・ＯＳ ｉ （ＯＣＲ３）３１
にゆっくりと加え、さらに充分混合しシリカゾルを得た
。以下実施例１と同様の操作を行って乾燥ゲルを得た。The resulting solution was mixed with 1 mol of silicon methoxide polycondensate ((CHz O)s St ・ (0-3i (OC
It was slowly added to Hs)z)n.OS i (OCR3)31 and thoroughly mixed to obtain a silica sol. Thereafter, the same operation as in Example 1 was performed to obtain a dry gel.
得られた乾燥ゲルにはクランクや割れは全くなかった。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−ゲ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。(Effects of the Invention) According to the present invention, large-sized silica glass without cranks or cracks can be easily manufactured by the sol-gel method. There are basically no restrictions on its size.
Claims (1)
し、これをゲル化し、乾燥して乾燥ゲルとし、次いで焼
結するシリカガラスの製造法に於て、シリコンアルコキ
シドを加水分解してシリカゾルとする段階で、ポリビニ
ルイソブチルエーテルを添加することを特徴とするシリ
カガラスの製造法。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, at the step of hydrolyzing silicon alkoxide to form silica sol, A method for producing silica glass characterized by adding polyvinyl isobutyl ether.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6997589A JPH02248332A (en) | 1989-03-22 | 1989-03-22 | Production of silica glass |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6997589A JPH02248332A (en) | 1989-03-22 | 1989-03-22 | Production of silica glass |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02248332A true JPH02248332A (en) | 1990-10-04 |
Family
ID=13418167
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6997589A Pending JPH02248332A (en) | 1989-03-22 | 1989-03-22 | Production of silica glass |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02248332A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6294601B1 (en) | 1997-10-29 | 2001-09-25 | Samsung Electronics Co., Ltd. | Silica glass composition |
-
1989
- 1989-03-22 JP JP6997589A patent/JPH02248332A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6294601B1 (en) | 1997-10-29 | 2001-09-25 | Samsung Electronics Co., Ltd. | Silica glass composition |
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