JP4371998B2

JP4371998B2 - Method for producing ultrafine quartz glass short fiber

Info

Publication number: JP4371998B2
Application number: JP2004378807A
Authority: JP
Inventors: 彰佐藤; 賞治高橋; 一男浅島; 朗藤ノ木; 裕幸西村; 隆矢口
Original assignee: YAMAGATA SHIN-ETSU QUARTZ PRODUCTS CO., LTD.; Shin Etsu Quartz Products Co Ltd
Current assignee: YAMAGATA SHIN-ETSU QUARTZ PRODUCTS CO., LTD.; Shin Etsu Quartz Products Co Ltd
Priority date: 2004-12-28
Filing date: 2004-12-28
Publication date: 2009-11-25
Anticipated expiration: 2024-12-28
Also published as: JP2006182610A

Description

本発明は、溶融法による極細石英ガラス短繊維の製造方法に関し、更に詳細には溶融法による極細石英ガラス短繊維の製造方法に関するものである。 The present invention relates to the production how ultrafine silica glass short fibers by melting method, more particularly it relates to the production how ultrafine silica glass short fibers by the melt process.

一般に、ガラス短繊維は溶融ガラスを高速で回転するスピナ中に供給し、スピナ中の周囲壁に設けられたオリフィスから遠心力で通過させることで得られる。
しかし、石英ガラスは通常のガラスとは異なり溶融状態となりにくく粘度が高いことから上記遠心法により短繊維を得ることが不可能である。そのため、石英ガラス短繊維またはシリカガラス短繊維を得る製造方法としては、水ガラスから製造する方法や酸によりＳｉＯ_２以外を溶出させる方法などが知られている。
しかし、これらの製造方法では、ＳｉＯ_２以外の不純物を多く含むことから、フィルター用途や半導体工業用途などクリーンな雰囲気を求める分野には不向きであった。
またさらに、溶融法による石英ガラス繊維の製造方法も公知となっている。
この製造方法によると石英ガラスロッドをバーナー火炎で延伸して石英ガラスを繊維化し、更に、作製した石英ガラス連続繊維を連続的に送り方向と同軸に設置されたバーナーにて吹き飛ばすことで直径２μｍ以上の石英ガラス短繊維を作製する。
上記の方法は、一連の工程で石英ガラスロッドから石英ガラス短繊維を作製することができ、工程を簡略化し、低コスト化が可能である。
しかしながら、直径２μｍ以上の石英ガラス繊維は非常に折れやすく、取扱の時に手に刺さったり、石英ガラス繊維の粉末が飛散して雰囲気を汚染するという問題があった。
そこで、本発明の発明者らは、上記の方法により、直径が２μｍ未満の極細石英ガラス短繊維の製造を試みたが、ショット（非繊維状粒子）が非常に多く発生し、効率が大変に悪かった。
発明者らが、その原因を鋭意検討したところ、直径２μｍ未満の石英ガラス短繊維を得るためには、石英ガラス連続繊維をかなり低速度にてバーナー火炎中に導入する必要があるが、上記の製造方法では、一連の工程で石英ガラスロッドから石英ガラス短繊維を作製することから、上記導入速度と石英ガラスロッドから石英ガラス連続繊維を延伸する速度が同速度であり、しかも該導入速度がかなり低速度であることから、石英ガラス短繊維を作製するための石英ガラス連続繊維の径の変化が生じやすく、径が安定しないことにあると知見した。
特公昭４２−１３７４８号特公昭３５−３１０９号特公昭６３−２７４４６号英国特許第５０７，９５１号 In general, short glass fibers are obtained by feeding molten glass into a spinner rotating at high speed and passing it through an orifice provided on a peripheral wall of the spinner by centrifugal force.
However, unlike ordinary glass, quartz glass is unlikely to be in a molten state and has a high viscosity. Therefore, it is impossible to obtain short fibers by the centrifugal method. Therefore, known methods for producing quartz glass short fibers or silica glass short fibers include a method of producing from water glass and a method of eluting materials other than SiO _{2 with an} acid.
However, these production methods contain many impurities other than SiO ₂ , and are not suitable for fields requiring a clean atmosphere such as filter applications and semiconductor industry applications.
Furthermore, a method for producing quartz glass fiber by a melting method is also known.
According to this manufacturing method, a quartz glass rod is drawn with a burner flame to fiberize the quartz glass, and further, the produced quartz glass continuous fiber is continuously blown off with a burner installed coaxially with the feeding direction to have a diameter of 2 μm or more. Quartz glass short fibers are prepared.
In the above method, a short silica glass fiber can be produced from a quartz glass rod in a series of steps, and the process can be simplified and the cost can be reduced.
However, quartz glass fibers having a diameter of 2 μm or more are very easy to break, and there are problems that they are stuck in the hands during handling and the silica glass fiber powder is scattered to contaminate the atmosphere.
Therefore, the inventors of the present invention tried to produce ultrafine quartz glass short fibers having a diameter of less than 2 μm by the above method, but very many shots (non-fibrous particles) were generated and the efficiency was very high. It was bad.
The inventors have intensively studied the cause, and in order to obtain a short silica glass fiber having a diameter of less than 2 μm, it is necessary to introduce the continuous silica glass fiber into the burner flame at a considerably low speed. In the production method, since the short silica glass fiber is produced from the quartz glass rod in a series of steps, the introduction speed is equal to the speed at which the continuous silica glass fiber is drawn from the quartz glass rod, and the introduction speed is considerably high. Since the speed was low, it was found that the diameter of the continuous silica glass fiber for producing the short silica glass fiber was likely to change, and the diameter was not stable.
Japanese Patent Publication No.42-13748 Japanese Patent Publication No.35-3109 JP-B 63-27446 British Patent No. 507,951

本発明は、上記の知見に基づくものであり、その目的は、繊維径を極細にできると共に、発生するショットの数を低下させることができ、要求品質に合致した極細石英ガラス短繊維を連続的、安定的に製造できる極細石英ガラス短繊維の製造方法を提供することにある。 The present invention is based on the above-mentioned knowledge, and the purpose thereof is to make the fiber diameter extremely fine and to reduce the number of shots generated, and to continuously produce ultrafine quartz glass short fibers that meet the required quality. is to provide a manufacturing how ultrafine silica glass short fibers can be produced stably.

本発明は、上記目的を達成するため以下の構成を備える。すなわち、本発明は、直径２ｍｍから１００ｍｍの石英ガラスロッドを、巻取り手段で巻取りながら加熱延伸して直径０．１ｍｍから０．４ｍｍで１ｍ当たりの直径変動率が±１０％以下の石英ガラス連続繊維を作製する工程と、作製した石英ガラス連続繊維を前記巻取り手段から繰り出し、そのバーナー火炎への導入量が４ｍｍ^３／ｍｉｎ以上７０ｍｍ^３／ｍｉｎ以下でその変動率が±１０％以下となるように、線速が５０ｍ／ｓ以上５００ｍ／ｓ以下でその変動率±５％以下であるバーナー火炎に導入して石英ガラス連続繊維を吹き飛ばすことで、直径０．１μｍ以上２．０μｍ未満のものの頻度が５０％以上含む石英ガラス短繊維を作製する工程を備える極細石英ガラス短繊維の製造方法である。
上記バーナー火炎は、酸素と水素の混合ガス、または酸素とプロパンの混合ガスのバーナー火炎であることが好ましい。 In order to achieve the above object, the present invention comprises the following arrangement. That is, the present invention is a quartz glass rod having a diameter variation of 0.1 mm to 0.4 mm and a diameter variation rate of ± 10% or less with a diameter of 0.1 mm to 0.4 mm by winding a quartz glass rod having a diameter of 2 mm to 100 mm while being wound by a winding means. The step of producing continuous fibers, and the produced quartz glass continuous fibers are unwound from the winding means, and the amount introduced into the burner flame is 4 mm ³ / min to 70 mm ³ / min and the variation rate is ± 10% or less. By introducing into a burner flame that has a linear velocity of 50 m / s or more and 500 m / s or less and a variation rate of ± 5% or less, and blowing silica glass continuous fibers, the diameter is 0.1 μm or more and less than 2.0 μm. This is a method for producing an ultrafine quartz glass short fiber comprising a step of producing a quartz glass short fiber containing a frequency of 50% or more.
The burner flame is preferably a burner flame of a mixed gas of oxygen and hydrogen or a mixed gas of oxygen and propane.

また、バーナー火炎と同軸方向に石英ガラス連続繊維をバーナー火炎へ導入することが好ましい。
また、複数の巻き取り手段から石英ガラス連続繊維複数本を繰り出し、これらを同一の火炎中に同時に導入することが好ましい。
また、石英ガラスロッドを加熱延伸して石英ガラス連続繊維を作製する工程における加熱方法は、酸素と水素の混合ガスまたは酸素とプロパンの混合ガスによるバーナー火炎、または電気炉であることが好ましい。 Moreover, it is preferable to introduce a continuous silica glass fiber into the burner flame in a direction coaxial with the burner flame.
Further, it is preferable to feed out a plurality of continuous silica glass fibers from a plurality of winding means and introduce them simultaneously into the same flame.
Moreover, it is preferable that the heating method in the process of producing a quartz glass continuous fiber by heating and stretching a quartz glass rod is a burner flame or an electric furnace using a mixed gas of oxygen and hydrogen or a mixed gas of oxygen and propane.

前記巻き取り手段は、石英ガラス製であることが好ましい。また、製造された極細石英ガラス短繊維は、石英ガラス製の捕集治具により回収することが好ましい。
また、用いる石英ガラスロッドは、その不純物が、アルカリ金属であるＮａ、Ｋ、Ｌｉの総和が０．５ｐｐｍ以下、アルカリ土類金属であるＣａ、Ｍｇの総和が０．５ｐｐｍ以下、Ａｌが１ｐｐｍ以下であることが好ましい。
更に、本発明の製造方法により製造された極細石英ガラス短繊維は、直径０．１μｍ以上２．０μｍ未満のものの頻度が５０％以上、繊維長が１ｍｍ以上１０００ｍｍ以下、アルカリ金属であるＮａ、Ｋ、Ｌｉの総和が０．５ｐｐｍ以下、アルカリ土類金属であるＣａ、Ｍｇの総和が０．５ｐｐｍ以下、Ａｌが１ｐｐｍ以下であることが好ましい。
本発明の製造方法により製造された極細石英ガラス短繊維は、遷移金属であるＦｅ、Ｃｏ、Ｎｉの総和が１ｐｐｍ以下、Ｂが１ｐｐｍ以下、Ｐが１ｐｐｍ以下であることが好ましい。 The winding means is preferably made of quartz glass. Moreover, it is preferable to collect the produced ultrafine quartz glass short fibers with a collection jig made of quartz glass.
Moreover, the quartz glass rod to be used has impurities whose total content of alkali metals Na, K, Li is 0.5 ppm or less, the total of alkaline earth metals Ca, Mg is 0.5 ppm or less, and Al is 1 ppm or less. It is preferable that
Furthermore, the ultrafine silica glass short fiber manufactured by the manufacturing method of the present invention has a frequency of 50% or more of fibers having a diameter of 0.1 μm or more and less than 2.0 μm, a fiber length of 1 mm or more and 1000 mm or less, and Na, K which are alkali metals. , Li is preferably 0.5 ppm or less, Ca, Mg, which are alkaline earth metals, is 0.5 ppm or less, and Al is preferably 1 ppm or less.
The ultrafine quartz glass short fiber produced by the production method of the present invention preferably has a total of transition metals Fe, Co, and Ni of 1 ppm or less, B of 1 ppm or less, and P of 1 ppm or less.

本発明の極細石英ガラス短繊維の製造方法によれば、径の変動率が小さい石英ガラス連続繊維を、変動率の小さい一定速度でバーナー火炎中に導入しているので、製造中のショットの発生を極めて抑制した状態で極細石英ガラス短繊維を連続的にかつ安定して製造することができる。
また、本発明の極細石英ガラス短繊維は、繊維径が細いことから非常にしなやかであり、取扱時に石英ガラス繊維の粉末が飛散することが少なく、さらに溶融法により製造することから不純物が非常に少なく、清浄な雰囲気が求められる半導体工業やバイオテクノロジー分野での断熱材やフィルター、さらに絶縁特性が求められる炉材やプリント配線板用基材などに使用が可能となる。 According to the method for producing ultrafine silica glass short fibers of the present invention, continuous silica glass fibers having a small variation rate of diameter are introduced into the burner flame at a constant speed with a small variation rate, so that the generation of shots during production It is possible to continuously and stably produce ultrafine quartz glass short fibers in a state where is extremely suppressed.
In addition, the ultrafine silica glass short fiber of the present invention is very flexible because the fiber diameter is thin, and the silica glass fiber powder is less likely to scatter during handling, and furthermore, since it is manufactured by a melting method, impurities are very high. It can be used for heat insulating materials and filters in the semiconductor industry and the biotechnology field where a clean atmosphere is required, and for furnace materials and printed wiring board substrates that require insulating properties.

以下に本発明の実施の形態を添付図面に基づいて説明するが、図示例は例示的に示されるもので、本発明の技術思想から逸脱しない限り種々の変形が可能なことは言うまでもない。
本発明の実施の態様による極細石英ガラス短繊維の製造方法は、図１に示すように、石英ガラスロッドを加熱延伸して石英ガラス連続繊維を作製する石英ガラス連続繊維作製工程と、この石英ガラス連続繊維を巻き取り手段により巻き取る工程と、巻き取り手段から石英ガラス連続繊維を繰り出す工程と、この繰り出されたた石英ガラス連続繊維をバーナー火炎にて極細石英ガラス短繊維に短繊維化する短繊維化工程と、この極細石英ガラス短繊維を捕集治具により捕集する捕集工程とを備える。すなわち、本発明においては、石英ガラスロッドを延伸して形成された石英ガラス連続繊維は、ドラムやローラー等の巻き取り手段により一旦巻き取ることを特長の一つとしている。これにより、石英ガラス連続繊維の径の安定性が大きく向上する。なお、本明細書において、石英ガラスとは、天然石英ガラスおよび合成石英ガラスの両者を含むものとする。 DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. However, the illustrated examples are illustrative only, and various modifications can be made without departing from the technical idea of the present invention.
As shown in FIG. 1, a method for producing ultrafine quartz glass short fibers according to an embodiment of the present invention includes a quartz glass continuous fiber production step of producing a quartz glass continuous fiber by heating and stretching a quartz glass rod, and this quartz glass. A step of winding the continuous fiber by a winding means, a step of feeding the continuous silica glass fiber from the winding means, and a short process for shortening the drawn continuous silica glass fiber to an ultrafine quartz glass short fiber by a burner flame. A fiberizing step, and a collecting step of collecting the ultrafine quartz glass short fibers with a collecting jig. That is, in the present invention, it is one of the features that the continuous silica glass fiber formed by stretching the silica glass rod is temporarily wound by a winding means such as a drum or a roller. Thereby, the stability of the diameter of the quartz glass continuous fiber is greatly improved. In the present specification, quartz glass includes both natural quartz glass and synthetic quartz glass.

次に、図２、図３および図４を参照して、上記石英ガラス連続繊維作製工程、短繊維化工程および捕集工程について詳細に説明する。
図２に示されているように、石英ガラス連続繊維工程においては、直径２ｍｍから１００ｍｍの石英ガラスロッド１を溶融方向に送りながら溶融端を引き出し、加熱具２で加熱溶融しながら延伸して、直径０．１ｍｍから０．４ｍｍの石英ガラス連続繊維３を作製する。用いる石英ガラスロッドは、その不純物が、アルカリ金属であるＮａ、Ｋ、Ｌｉの総和が０．５ｐｐｍ以下、アルカリ土類金属であるＣａ、Ｍｇの総和が０．５ｐｐｍ以下、Ａｌが１ｐｐｍ以下であることが好ましい。なお、得られた石英ガラス連続繊維は、石英ガラス製の巻き取り具８により巻き取られる。延伸は、この巻き取りにより行われるが、石英ガラスロッドの導入量は２００ｍｍ^３／ｍｉｎから２０００ｍｍ^３／ｍｉｎ程度が好ましく、この巻き取り速度すなわち延伸速度は、３ｍ／ｍｉｎから５０ｍ／ｍｉｎ程度が好ましい。延伸速度が、速すぎると、石英ガラスロッドが充分に加熱されず、作製した石英ガラス連続繊維にひずみが生じ、非常に脆くなり、切れやすくなる。また、遅すぎると溶融端の形状が安定せず、得られる石英ガラス連続繊維の径が安定せず、ショットの原因となる。以上の工程により、直径が０．１から０．４ｍｍで、１ｍ当たりの直径の変動率が±１０％以下の石英ガラス連続繊維が得られる。石英ガラス連続繊維の直径が上記の範囲未満であると、バーナー火炎への導入速度が速くなり取扱が非常に難しくなり、上記の範囲を超えると、巻取り具の直径が大きくなり実使用に耐え得ない。また、上記したように、石英ガラス連続繊維の直径の変動率が上記の範囲を超えると、ショットの原因となる。なお、上記加熱具としては、酸素と水素の混合ガスまたは酸素とプロパンによるバーナー火炎を発生するバーナーあるいは抵抗加熱式の電気炉を用いることができる。 Next, with reference to FIG. 2, FIG. 3, and FIG. 4, the said quartz glass continuous fiber preparation process, a fiber shortening process, and a collection process are demonstrated in detail.
As shown in FIG. 2, in the quartz glass continuous fiber process, the quartz glass rod 1 having a diameter of 2 mm to 100 mm is drawn in the melting direction, the melting end is pulled out, and the heating tool 2 is heated and melted and stretched. A quartz glass continuous fiber 3 having a diameter of 0.1 mm to 0.4 mm is produced. The quartz glass rod used has impurities of 0.5 ppm or less in total of alkali metals Na, K, Li, 0.5 ppm or less in total of Ca and Mg as alkaline earth metals, and 1 ppm or less in Al. It is preferable. In addition, the obtained quartz glass continuous fiber is wound up by the winder 8 made from quartz glass. Stretching is performed by this winding, and the introduction amount of the quartz glass rod is preferably about 200 mm ³ / min to 2000 mm ³ / min, and the winding speed, that is, the stretching speed is preferably about 3 m / min to 50 m / min. . If the drawing speed is too high, the quartz glass rod is not sufficiently heated, and the produced continuous silica glass fiber is distorted, and becomes very brittle and easily cut. On the other hand, if it is too slow, the shape of the melt end will not be stable, and the diameter of the resulting continuous silica glass fiber will not be stable, causing a shot. Through the above steps, a quartz glass continuous fiber having a diameter of 0.1 to 0.4 mm and a variation rate of the diameter per meter of ± 10% or less is obtained. When the diameter of the continuous silica glass fiber is less than the above range, the introduction speed into the burner flame becomes high and handling becomes very difficult. When the diameter exceeds the above range, the diameter of the winder becomes large and can withstand actual use. I don't get it. Further, as described above, if the variation rate of the diameter of the quartz glass continuous fiber exceeds the above range, it causes a shot. As the heating tool, a mixed gas of oxygen and hydrogen, a burner that generates a burner flame with oxygen and propane, or a resistance heating type electric furnace can be used.

図３に示されているように、短繊維化工程では、上記巻き取り具８から繰り出された直径０．１から０．４ｍｍの石英ガラス連続繊維を、線速が５０ｍ／ｓ以上５００ｍ／ｓ以下でその変動率が±５以下の酸素と水素の混合ガス、または酸素とプロパンの混合ガスのバーナー火炎中に、石英ガラス連続繊維の導入量が４ｍｍ^３／ｍｉｎ以上７０ｍｍ^３／ｍｉｎ以下でその変動率が±１０％以下となるように、ニップローラー４により、石英ガラス連続繊維をバーナー火炎と同軸方向に導入することで、極細石英ガラス短繊維を作製する。この工程では、上記したように、直径０．１ｍｍから０．４ｍｍの石英ガラス連続繊維と同軸方向に燃焼している混合ガス火炎中に導入することで、石英ガラス連続繊維を溶融し、さらに燃焼ガスの圧力により溶融した繊維を吹き飛ばすことで石英ガラス短繊維を作製する。上記ニップローラーは、石英ガラス製、特に合成石英ガラス製であることが好ましい。 As shown in FIG. 3, in the fiber shortening step, a continuous silica glass fiber having a diameter of 0.1 to 0.4 mm fed from the winder 8 has a linear velocity of 50 m / s to 500 m / s. In the following, when the introduction rate of the continuous silica glass fiber is 4 mm ³ / min or more and 70 mm ³ / min or less in the burner flame of the mixed gas of oxygen and hydrogen or the mixed gas of oxygen and propane whose variation rate is ± 5 or less The ultrafine silica glass short fiber is produced by introducing the silica glass continuous fiber in the coaxial direction with the burner flame by the nip roller 4 so that the variation rate becomes ± 10% or less. In this step, as described above, the silica glass continuous fiber is melted by being introduced into the mixed gas flame that is combusted in the coaxial direction with the silica glass continuous fiber having a diameter of 0.1 mm to 0.4 mm, and further burned. Silica glass short fibers are produced by blowing away the melted fibers by the gas pressure. The nip roller is preferably made of quartz glass, particularly synthetic quartz glass.

上記バーナー火炎の線速の変動率を上記したように±５％以下にするには、例えば、マスフローコントローラーや面積流量計などの高精度な流量制御装置を使用すればよい。また、上記導入量の変動率を上記したように±１０％以下にするには、例えば、サーボモーターやステッピングモーターなどの高精度な制御モーターを使用すればよい。
バーナー火炎の線速が上記の範囲未満であると、ガス圧力が不足しショットの発生数が多くなったり石英ガラス短繊維の径が太くなったりし、上記の範囲を超えても極細石英ガラス短繊維を得ることができるが経済的に無駄が多くなる。また、その変動率が上記の範囲を超えると、ショットの発生数は非常に多くなる。
上記導入量が上記の範囲未満であると、ショットの発生数が非常に多くなり、上記の範囲を超えると、石英ガラス短繊維の径が太くなる。また、その変動率が上記の範囲を超えると、ショットの発生数が多くなる。
以上の工程により、繊維径が直径０．１μｍ以上２．０μｍ未満のものの頻度が５０％以上の極細石英ガラス短繊維が得られる。 In order to set the fluctuation rate of the linear speed of the burner flame to ± 5% or less as described above, for example, a highly accurate flow rate control device such as a mass flow controller or an area flow meter may be used. Further, in order to set the variation rate of the introduction amount to ± 10% or less as described above, for example, a highly accurate control motor such as a servo motor or a stepping motor may be used.
If the linear velocity of the burner flame is less than the above range, the gas pressure will be insufficient, the number of shots will increase, the diameter of the short silica glass fiber will become thick, and even if it exceeds the above range, the ultrafine silica glass will be short. Although fibers can be obtained, waste is increased economically. Further, when the variation rate exceeds the above range, the number of shots generated becomes very large.
If the introduction amount is less than the above range, the number of shots generated is very large, and if it exceeds the above range, the diameter of the quartz glass short fiber becomes large. Further, when the variation rate exceeds the above range, the number of shots generated increases.
Through the above steps, ultrafine silica glass short fibers having a fiber diameter of 50% or more with a diameter of 0.1 μm or more and less than 2.0 μm are obtained.

図４に示されているように、捕集工程では、上記短繊維化工程で作製され、吹き飛ばされた極細石英ガラス短繊維を導入管６内に吹き飛ばし、石英ガラス繊維捕集用治具７で極細石英ガラス短繊維を捕集する。上記導入管や繊維捕集用治具は、石英ガラス、特に合成石英ガラス製であることが好ましい。材質を石英ガラス特に合成石英ガラスとすることで捕集用治具や導入管からの汚染が無くなる為である。繊維捕集用治具は、石英ガラスロッドを等間隔に並べた形状や、網状に加工した形状が用いられ、石英ガラス短繊維が捕集可能であれば、形状に制約はない。 As shown in FIG. 4, in the collection process, the ultrafine quartz glass short fibers produced and blown off in the shortening process are blown into the introduction tube 6, and the quartz glass fiber collection jig 7 is used. Collects ultrafine quartz glass short fibers. The introduction tube and the fiber collecting jig are preferably made of quartz glass, particularly synthetic quartz glass. This is because contamination from the collecting jig and the introduction tube is eliminated by using quartz glass, particularly synthetic quartz glass. As the fiber collecting jig, a shape in which quartz glass rods are arranged at equal intervals or a shape processed into a net shape is used, and there is no restriction on the shape as long as short glass fibers can be collected.

本発明の製造方法によれば、ショットの発生が極めて少なく、従来の石英ガラス短繊維よりも不純物が非常に少なく、清浄な雰囲気が求められる半導体工業やバイオテクノロジー分野での断熱材やフィルター、さらに絶縁特性が求められる炉材やプリント配線板用基材などの使用に好適な極細石英ガラス短繊維を製造できる。
本発明のは、繊維径が直径０．１μｍ以上２．０μｍ未満のものの頻度が５０％以上、繊維長が１ｍｍ以上１０００ｍｍ以下、アルカリ金属であるＮａ、Ｋ、Ｌｉの総和が０．５ｐｐｍ以下、アルカリ土類金属であるＣａ、Ｍｇの総和が０．５ｐｐｍ以下、Ａｌが１ｐｐｍ以下である極細石英ガラス短繊維を提供するものである。ここで、上記頻度とは、石英ガラス連続繊維を吹き飛ばして作製した短繊維全本中に占める本数の割合をいう。
また、遷移金属であるＦｅ、Ｃｏ、Ｎｉの総和が１ｐｐｍ以下、Ｂが１ｐｐｍ以下、Ｐが１ｐｐｍ以下である極細石英ガラス短繊維を提供するものである。
本極細石英ガラス短繊維の製造方法においては、複数の巻き取り具から石英ガラス連続繊維複数本を繰り出し、これらを同一の火炎中に同時に導入することによって極細石英ガラス短繊維を製造してもよい。火炎中に同時に導入する石英ガラス連続繊維の本数としては、１〜５本程度が好ましい。 According to the production method of the present invention, the occurrence of shots is extremely small, impurities are much less than conventional quartz glass short fibers, and heat insulating materials and filters in the semiconductor industry and biotechnology field where a clean atmosphere is required, It is possible to produce ultrafine quartz glass short fibers suitable for use in furnace materials, printed wiring board base materials, and the like that require insulating properties.
According to the present invention, the frequency of fibers having a diameter of 0.1 μm or more and less than 2.0 μm is 50% or more, the fiber length is 1 mm or more and 1000 mm or less, and the total of Na, K, and Li that are alkali metals is 0.5 ppm or less, The present invention provides an ultrafine quartz glass short fiber in which the total of Ca and Mg, which are alkaline earth metals, is 0.5 ppm or less and Al is 1 ppm or less. Here, the above-mentioned frequency refers to the ratio of the number of the short fibers produced by blowing away the continuous silica glass fibers.
Further, the present invention provides an ultrafine quartz glass short fiber in which the total of transition metals Fe, Co, and Ni is 1 ppm or less, B is 1 ppm or less, and P is 1 ppm or less.
In the method for producing the ultrafine silica glass short fiber, the ultrafine quartz glass short fiber may be produced by feeding a plurality of continuous silica glass fibers from a plurality of winders and simultaneously introducing them into the same flame. . The number of continuous quartz glass fibers introduced simultaneously into the flame is preferably about 1 to 5.

実施例１
図２〜図４に示す工程で、極細石英ガラス短繊維を製造した。すなわち、酸素と水素の混合ガスのバーナー火炎を用い、直径２０ｍｍの石英ガラスロッドを４８５ｍｍ^３／ｍｉｎで導入し、石英ガラス製の巻き取り具により巻き取り速度５ｍ／ｍｉｎで巻き取りながら、加熱延伸して石英ガラス連続繊維を作製した。作製された石英ガラス連続繊維の直径は０．３５ｍｍであり、直径の１ｍ当たりの変動率は、その全長において、±１０％以下であった。ついで、酸素と水素の混合ガスの線速が２４０ｍ／ｓで、その変動率が±５％以下であるバーナー火炎中に、上記巻き取り具から繰り出した石英ガラス連続繊維を９ｍｍ^３／ｍｉｎ（変動率±１０％以下）で導入し、極細石英ガラス短繊維を得た。上記線速の変動率を上記にするため、酸素と水素をそれぞれマスフローコントローラーにより流量を制御した。また、上記導入量の変動率を上記とするため、サーボモーターによりニップローラーの回転数を制御した。また、ニップローラー、導入管、捕集治具は石英ガラス製のものを用いた。
得られた極細石英ガラス短繊維の特長を表１に、繊維径分布を図5に示した。また、原子吸光法により不純物濃度を測定し、表２に示した。 Example 1
The ultrafine quartz glass short fiber was manufactured by the process shown in FIGS. That is, using a burner flame of a mixed gas of oxygen and hydrogen, a quartz glass rod having a diameter of 20 mm was introduced at 485 mm ³ / min, and the film was heated and drawn while being wound at a winding speed of 5 m / min by a winder made of quartz glass. Thus, a continuous silica glass fiber was produced. The diameter of the produced quartz glass continuous fiber was 0.35 mm, and the variation rate per 1 m of the diameter was ± 10% or less in the entire length. Then, the quartz glass continuous fiber fed from the winder is 9 mm ³ / min (variation) in a burner flame where the linear velocity of the mixed gas of oxygen and hydrogen is 240 m / s and the variation rate is ± 5% or less. Then, an ultrafine quartz glass short fiber was obtained. In order to make the fluctuation rate of the linear velocity above, the flow rates of oxygen and hydrogen were controlled by a mass flow controller. Further, in order to set the variation rate of the introduction amount as described above, the rotation speed of the nip roller was controlled by a servo motor. Moreover, the thing made from quartz glass was used for the nip roller, the introduction tube, and the collection jig.
The characteristics of the obtained ultrafine silica glass short fibers are shown in Table 1, and the fiber diameter distribution is shown in FIG. Further, the impurity concentration was measured by an atomic absorption method and shown in Table 2.

実施例２
酸素とプロパンの混合ガスのバーナー火炎を用い、直径４ｍｍの石英ガラスロッドを１８８４ｍｍ^３／ｍｉｎで導入し、石英ガラス製の巻き取り具により巻き取り速度３８ｍ／ｍｉｎで巻き取りながら、加熱延伸して石英ガラス連続繊維を作製した。作製された石英ガラス連続繊維の直径は０．２５ｍｍであり、直径の１ｍ当たりの変動率は、その全長において、±１０％以下であった。ついで、酸素と水素の混合ガスの線速が２９０ｍ／ｓで、その変動率が±５％以下であるバーナー火炎中に、上記巻き取り具から繰り出した石英ガラス連続繊維を２８ｍｍ^３／ｍｉｎ（変動率±１０％以下）で導入し、極細石英ガラス短繊維を得た。上記線速の変動率および上記導入量の変動率を上記とするには、実施例１と同様の手段を採用した。また、ニップローラー、導入管、捕集治具は石英ガラス製のものを用いた。得られた極細石英ガラス短繊維の特長を表１に、繊維径分布を図６に示した。 Example 2
Using a burner flame of a mixed gas of oxygen and propane, a quartz glass rod with a diameter of 4 mm was introduced at 1884 mm ³ / min, and heated and stretched while being wound at a winding speed of 38 m / min by a winder made of quartz glass. Quartz glass continuous fiber was produced. The diameter of the produced quartz glass continuous fiber was 0.25 mm, and the variation rate per 1 m of the diameter was ± 10% or less in the entire length. Next, the quartz glass continuous fiber drawn out from the winder is 28 mm ³ / min (variation) in a burner flame where the linear velocity of the mixed gas of oxygen and hydrogen is 290 m / s and the variation rate is ± 5% or less. Then, an ultrafine quartz glass short fiber was obtained. The same means as in Example 1 was adopted in order to set the linear velocity variation rate and the introduction amount variation rate as described above. Moreover, the thing made from quartz glass was used for the nip roller, the introduction tube, and the collection jig. The characteristics of the obtained ultrafine silica glass short fibers are shown in Table 1, and the fiber diameter distribution is shown in FIG.

実施例３
抵抗加熱式の電気炉を用い、直径８ｍｍの石英ガラスロッドを８０３ｍｍ^３／ｍｉｎで導入し、石英ガラス製の巻き取り具により巻き取り速度４５ｍ／ｍｉｎで巻き取りながら、加熱延伸して石英ガラス連続繊維を作製した。作製された石英ガラス連続繊維の直径は０．１５ｍｍであり、直径の１ｍ当たりの変動率は、その全長において、±１０％以下であった。ついで、酸素と水素の混合ガスの線速が４７０ｍ／ｓで、その変動率が±５％以下であるバーナー火炎中に、上記巻き取り具から繰り出した石英ガラス連続繊維を６５ｍｍ^３／ｍｉｎ（変動率±１０％以下）で導入し、極細石英ガラス短繊維を得た。上記線速の変動率および上記導入量の変動率を上記とするには、実施例１と同様の手段を採用した。また、ニップローラー、導入管、捕集治具は石英ガラス製のものを用いた。得られた石英ガラス短繊維の特長を表１に、繊維径分布を図７に示した。 Example 3
Using a resistance heating type electric furnace, a quartz glass rod having a diameter of 8 mm was introduced at 803 mm ³ / min, and while being wound at a winding speed of 45 m / min with a winder made of quartz glass, the glass was continuously stretched by heating. Fibers were made. The diameter of the produced continuous silica glass fiber was 0.15 mm, and the variation rate per 1 m of the diameter was ± 10% or less over the entire length. Next, the quartz glass continuous fiber fed from the winder is 65 mm ³ / min (variation) in a burner flame where the linear velocity of the mixed gas of oxygen and hydrogen is 470 m / s and the variation rate is ± 5% or less. Then, an ultrafine quartz glass short fiber was obtained. The same means as in Example 1 was adopted in order to set the linear velocity variation rate and the introduction amount variation rate as described above. Moreover, the thing made from quartz glass was used for the nip roller, the introduction tube, and the collection jig. The characteristics of the obtained short silica glass fibers are shown in Table 1, and the fiber diameter distribution is shown in FIG.

比較例１
酸素と水素の混合ガスのバーナー火炎を用い、直径４ｍｍの石英ガラスロッドを３１５ｍｍ^３／ｍｉｎで導入し、石英ガラス製の巻き取り具により巻き取り速度２０ｍ／ｍｉｎで巻き取りながら、加熱延伸して石英ガラス連続繊維を作製した。作製された石英ガラス連続繊維の直径は０．２５ｍｍであり、直径の１ｍ当たりの変動率は、その全長において±１０％以下であった。ついで、酸素と水素の混合ガスの線速が４７０ｍ／ｓで、その変動率が５％以下であるバーナー火炎中に、上記巻き取り具から繰り出した石英ガラス連続繊維を７３ｍｍ^３／ｍｉｎ（変動率１０％以下）で導入し、極細石英ガラス短繊維を得た。得られた石英ガラス短繊維の特長を表１に、繊維径分布を図８に示した。 Comparative Example 1
Using a burner flame of a mixed gas of oxygen and hydrogen, a quartz glass rod having a diameter of 4 mm was introduced at 315 mm ³ / min, and heated and stretched while being wound at a winding speed of 20 m / min by a winder made of quartz glass. Quartz glass continuous fiber was produced. The diameter of the produced continuous silica glass fiber was 0.25 mm, and the variation rate per 1 m of the diameter was ± 10% or less over the entire length. Subsequently, the quartz glass continuous fiber drawn out from the winder is put into 73 mm ³ / min (variation rate) in a burner flame where the linear velocity of the mixed gas of oxygen and hydrogen is 470 m / s and the variation rate is 5% or less. 10% or less) to obtain ultrafine quartz glass short fibers. The features of the obtained short silica glass fibers are shown in Table 1, and the fiber diameter distribution is shown in FIG.

比較例２
抵抗加熱式の電気炉を用い、直径４ｍｍの石英ガラスロッドを１２７０ｍｍ^３／ｍｉｎで導入し、石英ガラス製の巻き取り具により巻き取り速度４０ｍ／ｍｉｎで巻き取りながら、加熱延伸して石英ガラス連続繊維を作製した。作製された石英ガラス連続繊維の直径は０．２ｍｍであり、直径の１ｍ当たりの変動率は、その全長において、±１０％以下であった。ついで、酸素と水素の混合ガスの線速が２００ｍ／ｓで、その変動率が±５％以下であるバーナー火炎中に、上記巻き取り具から繰り出した石英ガラス連続繊維を３ｍｍ^３／ｍｉｎ（変動率±１０％以下）で導入し、極細石英ガラス短繊維を得ようと試みたが、石英ガラス連続繊維とはならずショットのみ生じた。 Comparative Example 2
Using a resistance heating type electric furnace, a quartz glass rod having a diameter of 4 mm is introduced at 1270 mm ³ / min, and while being wound at a winding speed of 40 m / min by a winder made of quartz glass, it is heated and stretched to continue the quartz glass. Fibers were made. The diameter of the produced quartz glass continuous fiber was 0.2 mm, and the variation rate per meter of the diameter was ± 10% or less in the entire length. Next, the quartz glass continuous fiber drawn out from the winder is 3 mm ³ / min (variation) in a burner flame where the linear velocity of the mixed gas of oxygen and hydrogen is 200 m / s and the variation rate is ± 5% or less. At a rate of ± 10% or less, an attempt was made to obtain an ultrafine silica glass short fiber, but it was not a continuous silica glass fiber and only a shot was produced.

比較例３
抵抗加熱式の電気炉を用い、直径９０ｍｍの石英ガラスロッドを１４５７ｍｍ^３／ｍｉｎで導入し、石英ガラス製の巻き取り具により巻き取り速度１５ｍ／ｍｉｎで巻き取りながら、加熱延伸して石英ガラス連続繊維を作製した。作製された石英ガラス連続繊維の直径は０．３５ｍｍであり、直径の１ｍ当たりの変動率は、その全長において、±１０％以下であった。ついで、酸素と水素の混合ガスの線速が４０ｍ／ｓで、その変動率が±５％以下であるバーナー火炎中に、上記巻き取り具から繰り出した石英ガラス連続繊維を１０ｍｍ^３／ｍｉｎ（変動率±１０％以下）で導入し、極細石英ガラス短繊維を得た。上記線速の変動率および上記導入量の変動率を上記とするには、実施例１と同様の手段を採用した。また、ニップローラー、導入管、捕集治具は石英ガラス製のものを用いた。得られた石英ガラス短繊維の特長を表１に、繊維径分布を図９に示した。 Comparative Example 3
Using a resistance heating type electric furnace, a quartz glass rod having a diameter of 90 mm was introduced at 1457 mm ³ / min, and while being wound at a winding speed of 15 m / min with a winder made of quartz glass, the glass was continuously stretched by heating. Fibers were made. The diameter of the produced quartz glass continuous fiber was 0.35 mm, and the variation rate per 1 m of the diameter was ± 10% or less in the entire length. Next, the quartz glass continuous fiber drawn out from the winder is 10 mm ³ / min (variation) in a burner flame where the linear velocity of the mixed gas of oxygen and hydrogen is 40 m / s and the variation rate is ± 5% or less. Then, an ultrafine quartz glass short fiber was obtained. The same means as in Example 1 was adopted in order to set the linear velocity variation rate and the introduction amount variation rate as described above. Moreover, the thing made from quartz glass was used for the nip roller, the introduction tube, and the collection jig. The characteristics of the obtained short silica glass fibers are shown in Table 1, and the fiber diameter distribution is shown in FIG.

比較例４
モーター制御機構を用いなかったことで、石英ガラス連続繊維のバーナー火炎への導入量の変動率が±１０％を超えたこと以外は、実施例１と同様にして極細石英ガラス短繊維を作製した。得られた石英ガラス短繊維の特長を表１に、繊維径分布を図１０に示した。 Comparative Example 4
The ultrafine quartz glass short fiber was produced in the same manner as in Example 1 except that the fluctuation rate of the introduction amount of the silica glass continuous fiber into the burner flame exceeded ± 10% because the motor control mechanism was not used. . The features of the obtained short silica glass fibers are shown in Table 1, and the fiber diameter distribution is shown in FIG.

比較例５
流量制御機構を用いなかったことで、上記バーナー火炎の線速の変動率が±５％を超えたこと以外は、実施例１と同様にして極細石英ガラス短繊維を作製した。得られた石英ガラス短繊維の特長を表１に、繊維径分布を図１１に示した。 Comparative Example 5
Ultrafine quartz glass short fibers were produced in the same manner as in Example 1 except that the flow rate control mechanism was not used and the fluctuation rate of the linear speed of the burner flame exceeded ± 5%. The features of the obtained short silica glass fibers are shown in Table 1, and the fiber diameter distribution is shown in FIG.

比較例６
実施例１と同様に石英ガラス短繊維を作製し、金属製のネットにより捕集した。作製した石英ガラス短繊維を原子吸光法により不純物濃度を測定し、表２に示した。 Comparative Example 6
Silica glass short fibers were produced in the same manner as in Example 1 and collected by a metal net. The produced silica glass short fibers were measured for impurity concentration by atomic absorption method, and are shown in Table 2.

表１

Table 1

表２

Table 2

本発明の実施の形態における石英ガラスの形状変化の模式図である。It is a schematic diagram of the shape change of the quartz glass in embodiment of this invention. 本発明の石英ガラスロッドから石英ガラス連続繊維を作製する工程の概略図である。It is the schematic of the process of producing a quartz glass continuous fiber from the quartz glass rod of this invention. 本発明の石英ガラス連続繊維から石英ガラス短繊維を作製する工程の概略図である。It is the schematic of the process of producing a quartz glass short fiber from the quartz glass continuous fiber of this invention. 石英ガラス短繊維の捕集方法の概略図である。It is the schematic of the collection method of a quartz glass short fiber. 実施例１の繊維径分布図である。1 is a fiber diameter distribution diagram of Example 1. FIG. 実施例２の繊維径分布図である。6 is a fiber diameter distribution diagram of Example 2. FIG. 実施例３の繊維径分布図である。6 is a fiber diameter distribution diagram of Example 3. FIG. 比較例１の繊維径分布図である。6 is a fiber diameter distribution diagram of Comparative Example 1. FIG. 比較例３の繊維径分布図である。6 is a fiber diameter distribution diagram of Comparative Example 3. FIG. 比較例４の繊維径分布図である。6 is a fiber diameter distribution diagram of Comparative Example 4. FIG. 比較例５の繊維径分布図である。6 is a fiber diameter distribution diagram of Comparative Example 5. FIG.

Explanation of symbols

１：石英ガラスロッド
２：酸水素火炎バーナー
３：石英ガラス連続繊維
４：ニップローラー
５：酸水素火炎バーナー
６：石英ガラス製石英ガラス繊維導入管
７：石英ガラス製石英ガラス繊維捕集治具
８：巻取り具
1: Quartz glass rod 2: Oxyhydrogen flame burner 3: Quartz glass continuous fiber 4: Nip roller 5: Oxyhydrogen flame burner 6: Quartz glass quartz glass fiber introduction tube 7: Quartz glass quartz glass fiber collecting jig 8 : Winding tool

Claims

A quartz glass rod having a diameter of 2 mm to 100 mm is heated and stretched while being wound by a winding means to produce a quartz glass continuous fiber having a diameter variation of 0.1 mm to 0.4 mm and a variation rate of the diameter per meter of ± 10% or less. The process and the produced quartz glass continuous fiber are unwound from the winding means, and the amount of introduction into the burner flame is 4 mm ³ / min to 70 mm ³ / min and the variation rate is ± 10% or less. By introducing into a burner flame having a speed of 50 m / s or more and 500 m / s or less and a variation rate of ± 5% or less and blowing the continuous silica glass fiber, the frequency of those having a diameter of 0.1 μm or more and less than 2.0 μm is 50 The manufacturing method of the ultrafine quartz glass short fiber characterized by including the process of producing the quartz glass short fiber which is% or more.

2. The production of ultrafine silica glass short fibers according to claim 1, wherein the silica glass continuous fibers are blown off by a burner flame of a mixed gas of oxygen and hydrogen or a mixed gas of oxygen and propane to produce the short silica glass fibers. Method.

The method for producing ultrafine quartz glass short fibers according to claim 1 or 2, wherein the continuous silica glass fibers are introduced into the burner flame in a direction coaxial with the burner flame.

4. The production of ultrafine quartz glass short fibers according to any one of claims 1 to 3, wherein a plurality of continuous silica glass fibers are fed from a plurality of winding means, and these are simultaneously introduced into the same flame. Method.

The heating method in the step of producing a continuous silica glass fiber by heating and drawing a quartz glass rod is a burner flame or an electric furnace using a mixed gas of oxygen and hydrogen or a mixed gas of oxygen and propane. The manufacturing method of the ultrafine quartz glass short fiber in any one of Claims 1-4.

The method for producing ultrafine quartz glass short fibers according to any one of claims 1 to 5, wherein the winding means is made of quartz glass.

The method for producing ultrafine quartz glass short fibers according to any one of claims 1 to 6, wherein the ultrafine quartz glass short fibers are collected by a collection jig made of quartz glass.

As impurities of quartz glass rod, the sum of alkali metals Na, K, and Li is 0.5 ppm or less, the sum of alkaline earth metals Ca and Mg is 0.5 ppm or less, and Al is 1 ppm or less. A method for producing an ultrafine quartz glass short fiber according to any one of claims 1 to 7.