JP3516222B2 - Filter paper and air filter using the same - Google Patents
Filter paper and air filter using the sameInfo
- Publication number
- JP3516222B2 JP3516222B2 JP05861495A JP5861495A JP3516222B2 JP 3516222 B2 JP3516222 B2 JP 3516222B2 JP 05861495 A JP05861495 A JP 05861495A JP 5861495 A JP5861495 A JP 5861495A JP 3516222 B2 JP3516222 B2 JP 3516222B2
- Authority
- JP
- Japan
- Prior art keywords
- filter paper
- filter
- acid
- boron
- air
- 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.)
- Expired - Fee Related
Links
Landscapes
- Treating Waste Gases (AREA)
- Filtering Materials (AREA)
- Paper (AREA)
Description
【０００１】[0001]
【産業上の利用分野】この発明は、気体中の粒子及びガ
ス状ホウ素の捕集に利用されるろ紙及びこれを使用した
エアーフィルタに関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter paper used for collecting particles in a gas and gaseous boron and an air filter using the filter paper.
【０００２】[0002]
【従来の技術】従来のろ紙としては、例えば、ホウ珪酸
ガラス繊維を湿式抄紙したものにバインダー及び撥水剤
のエマルジョンを添加し、これを１３０℃程度のスチー
ムドライヤーで乾燥して構成させたものがある。2. Description of the Related Art As a conventional filter paper, for example, a borosilicate glass fiber prepared by wet papermaking is added with a binder and a water repellent emulsion, and dried by a steam dryer at about 130 ° C. There is.
【０００３】上記ろ紙を使用したエアーフィルタは塵埃
粒子を高い効率で捕集（０．３μｍ粒子を９９．９７％
以上）することができることから、現在、ＬＳＩ等電子
デバイス製造用クリーンルームの空気清浄化用として広
く使用されている。An air filter using the above filter paper collects dust particles with high efficiency (99.97% of 0.3 μm particles).
As described above, it is widely used for cleaning the air in a clean room for manufacturing electronic devices such as LSI.
【０００４】しかしながら、電子デバイスの集積度の向
上に伴い、電子デバイスのクリーンルーム内の空気への
暴露時間が長くなるにつれ、電子デバイスの特性が劣化
する現象が知られるようになってきた。この劣化の原因
の一つとして、エアーフィルタに使用されているホウ珪
酸ガラス繊維からのホウ素の放出がある。即ち、クリー
ンルーム内の空気は大部分が再循環されており、これが
製造途中の電子デバイスに付着しその特性を劣化させて
いるのである。However, as the degree of integration of electronic devices has improved, it has become known that the characteristics of the electronic device deteriorate as the exposure time of the electronic device to the air in the clean room becomes longer. One of the causes of this deterioration is the release of boron from the borosilicate glass fiber used in the air filter. That is, most of the air in the clean room is recirculated, which adheres to the electronic device in the process of manufacture and deteriorates its characteristics.
【０００５】そこで、わが社では、１ＧのＬＳＩをも製
造できるクリーンルームを提供できるろ紙、即ち、クリ
ーンルーム内のホウ素濃度を１０ｎｇ／ｍ3 以下に抑え
ることができるろ紙を研究開発し、出願（特願平６−２
８３１８１号）した。このろ紙は、ガラス繊維のろ材に
多価アルコール系の薬品を添着し、１１５℃以下のスチ
ームドライヤー（従来は１３０℃〜１５０℃）で乾燥さ
せたものである。しかしながら、このろ紙は製造時の乾
燥温度が低いためその時間を長くする必要があり、この
ため生産性が低いという問題があった。Therefore, our company researched and developed a filter paper that can provide a clean room capable of manufacturing 1G LSI, that is, a filter paper that can keep the boron concentration in the clean room at 10 ng / m 3 or less, and filed an application (patent application). Flat 6-2
83181). This filter paper is obtained by impregnating a glass fiber filter material with a polyhydric alcohol chemical and drying it with a steam dryer at 115 ° C or lower (conventionally 130 ° C to 150 ° C). However, since this filter paper has a low drying temperature at the time of production, it is necessary to extend the time, which causes a problem of low productivity.
【０００６】[0006]
【発明が解決しようとする課題】そこで、この発明で
は、生産性が低下せず、粒子を捕集でき且つホウ素濃度
を安定して１０ｎｇ／ｍ3 以下に抑えることができるろ
紙及びこれを利用したエアーフィルタを提供することを
課題とする。In view of the above, the present invention utilizes a filter paper which can collect particles without degrading the productivity and stably keep the boron concentration at 10 ng / m 3 or less. An object is to provide an air filter.
【０００７】[0007]
【課題を解決する為の手段】この発明のろ紙は、硫酸、
Ｌ−酒石酸、硝酸、クエン酸より選択された酸にてｐＨ
を３．０〜３．５にした水溶液に繊維径が０．２〜１２
μｍのガラス繊維を分散させて湿式抄紙し、この抄紙し
たものにＬ−酒石酸を添着して成る。Means for Solving the Problems The filter paper of the present invention comprises sulfuric acid,
PH with an acid selected from L-tartaric acid, nitric acid, and citric acid
The fiber diameter is 0.2 to 12 in an aqueous solution of 3.0 to 3.5.
It is formed by dispersing glass fibers having a diameter of μm, wet papermaking, and impregnating the papermaking material with L-tartaric acid.
【０００８】また、この発明のエアーフィルタは、上記
構成のろ紙を構成部材として成る。Further, the air filter of the present invention comprises the filter paper having the above construction as a constituent member.
【０００９】[0009]
【作用】この発明は次のように作用する。
抄紙したものにＬ−酒石酸を添着してあるから、Ｌ−
酒石酸とホウ素が化学的に結合することになり、その結
果、粒子を捕集することはむろんのこと、ガス状ホウ素
も捕集できる。
硫酸、Ｌ−酒石酸、硝酸、クエン酸より選択された酸
にてｐＨを３．０〜３．５にした水溶液にガラス繊維を
分散して湿式抄紙したものであるから、ガラス繊維の劣
化度合いが低く、このためホウ素の放出は低いものとな
る。
ガラス繊維を分散させる水溶液のｐＨ調整を硫酸、Ｌ
−酒石酸、硝酸、クエン酸により行っているから揮発性
の低い比較的安定な塩が生成されることとなり、スチー
ムドライヤーによる乾燥温度を下げることなくろ紙を製
造することができる。The present invention operates as follows. Since L-tartaric acid is impregnated on the paper made, L-
Tartaric acid and boron are chemically bound, and as a result, not only particles can be collected but also gaseous boron can be collected. Since glass fibers are dispersed in an aqueous solution having a pH of 3.0 to 3.5 with an acid selected from sulfuric acid, L-tartaric acid, nitric acid, and citric acid and wet papermaking, the degree of deterioration of glass fibers is Low, which results in low emission of boron. The pH of the aqueous solution in which the glass fibers are dispersed is adjusted with sulfuric acid, L
-Since tartaric acid, nitric acid, and citric acid are used, relatively stable salts with low volatility are generated, and filter paper can be manufactured without lowering the drying temperature by a steam dryer.
【００１０】以下、具体的に説明する。
〔実験１／ホウ素捕集試験〕ホウ珪酸繊維のろ紙に、Ｌ
−酒石酸をろ紙重量当たり７％添着しホウ素捕集率を測
定した。A detailed description will be given below. [Experiment 1 / Boron collection test] For filter paper of borosilicate fiber, L
-Tartaric acid was impregnated with 7% of the weight of the filter paper, and the boron collection rate was measured.
【００１１】図１に示す装置（図１中、符号１０ａ，１
０ｂは流量計、符号１１はメンブレンフィルタ、符号１
２はホウ酸水溶液、符号１３はメンブレンフィルタ、符
号１４は供試ろ紙、符号１５ａ，１５ｂ，１５ｃ，１５
ｄは純水、符号１６ａ，１６ｂは流量計を示す）によ
り、ろ紙１ｃｍ2 当たり３．５×１０3 ｎｇのホウ素
（クリーンルーム内の使用時間２．５×１０4 時間に相
当する）を負荷し、ろ紙の捕集率の測定を行った。ま
た、ろ紙の圧力損失についても測定を行った（通風速度
５．３ｃｍ／ｓ）。結果を表１に示す。この表１より、
Ｌ−酒石酸の添着により優れたホウ素捕集率となること
が明らかである。The apparatus shown in FIG. 1 (reference numerals 10a, 1 in FIG. 1)
0b is a flow meter, 11 is a membrane filter, 1
2 is a boric acid aqueous solution, 13 is a membrane filter, 14 is a sample filter paper, 15a, 15b, 15c, 15
d is pure water, and symbols 16a and 16b are flowmeters), and 3.5 × 10 3 ng of boron (corresponding to a use time of 2.5 × 10 4 hours in a clean room) per 1 cm 2 of filter paper is loaded. Then, the collection rate of the filter paper was measured. In addition, the pressure loss of the filter paper was also measured (ventilation speed 5.3 cm / s). The results are shown in Table 1. From this table 1,
It is clear that the impregnation of L-tartaric acid results in an excellent boron collection rate.
【００１２】[0012]
【表１】 [Table 1]
【００１３】〔実験２／ガラス繊維の分散方法とホウ素
発生量との関係を調べる試験〕ガラス繊維を硫酸水溶液
にて分散させ抄造後のろ紙に、（バインダー）＋（撥水
剤）＋（Ｌ酒石酸）のエマルジョンを含浸させた後、１
３０℃に加熱したスチームドライヤーでろ紙を乾燥させ
た。このときの分散のｐＨを変えてろ紙からのホウ素発
生量を図２の装置（符号２０は供試ろ紙、符号２１ａ，
２１ｂは純水入りバブラ、符号２２は流量計、符号２３
はエアーポンプを示す）にてホウ素発生量の試験（条
件：２２〜２４℃、湿度３５〜４０％ＲＨ）を行った。
その結果を図３に示す。硫酸のかわりにＬ−酒石酸も同
様に測定を行った。[Experiment 2 / Test for Examining Relationship between Dispersion Method of Glass Fiber and Boron Generation Amount] Glass fiber was dispersed in an aqueous solution of sulfuric acid, and (binder) + (water repellent) + (L Tartaric acid) and then 1
The filter paper was dried with a steam dryer heated to 30 ° C. At this time, the pH of the dispersion is changed and the amount of boron generated from the filter paper is measured by the apparatus shown in FIG. 2 (reference numeral 20 is a test filter paper, reference numeral 21a,
21b is a bubbler containing pure water, reference numeral 22 is a flow meter, reference numeral 23
Indicates an air pump), and a boron generation amount test (conditions: 22 to 24 ° C., humidity: 35 to 40% RH) was performed.
The result is shown in FIG. Instead of sulfuric acid, L-tartaric acid was also measured in the same manner.
【００１４】図３よりｐＨが高い方が好ましいことがわ
かる。よって、ホウ素発生量を安定して低く（５ｎｇ／
ｍ3 以下）するためにはｐＨを３．０以上にすることが
好ましいことが判る。さらに、ガラス繊維を均一に分散
させるｐＨは３．５以下であることより、分散させるｐ
Ｈは３．０〜３．５に限定される。It can be seen from FIG. 3 that higher pH is preferable. Therefore, the amount of boron generated is stable and low (5 ng /
m 3 or less) in order to it can be seen that it is preferable that 3.0 or more pH. Furthermore, since the pH at which the glass fibers are uniformly dispersed is 3.5 or less, the p
H is limited to 3.0 to 3.5.
【００１５】次に、ガラス繊維を均一に分散させる薬品
をかえて同様にホウ素発生量を測定した。その結果を表
２に示す。この表２よりガラス繊維を分散させる水溶液
のｐＨ調整に用いられる薬品は硫酸、Ｌ−酒石酸、硝
酸、クエン酸が好ましいことが判る。Next, the amount of boron generated was measured in the same manner by changing the chemicals for uniformly dispersing the glass fibers. The results are shown in Table 2. From Table 2, it is understood that sulfuric acid, L-tartaric acid, nitric acid and citric acid are preferable as the chemicals used for adjusting the pH of the aqueous solution in which the glass fibers are dispersed.
【００１６】[0016]
【表２】 [Table 2]
【００１７】[0017]
【実施例】この発明の実施例について説明する。Embodiments of the present invention will be described.
【００１８】この実施例のエアーフィルタは、アルミニ
ウム型材の枠に断面ジグザグ状に折り曲げられたろ紙を
外周気密状態に取り付けたものであり、前記ろ紙は、基
礎材料としてホウ珪酸ガラス繊維から成る細径繊維（繊
維径分布０．２〜２．６５μｍ、平均径０．８５μｍ）
と、前記細径繊維相互を補強するための少量の太径繊維
（Ｅガラス繊維：繊維径分布８〜２４μｍ）と、これら
に添着された紙重量の７％のＬ−酒石酸とから構成され
ている。In the air filter of this embodiment, a filter paper folded in a zigzag cross section is attached to an outer frame of an aluminum mold in a hermetically sealed state, and the filter paper has a small diameter made of borosilicate glass fiber as a basic material. Fiber (fiber diameter distribution 0.2-2.65 μm, average diameter 0.85 μm)
And a small amount of large-diameter fibers (E glass fiber: fiber diameter distribution 8 to 24 μm) for reinforcing the small-diameter fibers, and 7% by weight of paper of L-tartaric acid attached to these fibers. There is.
【００１９】このエアーフィルタは、以下の〜の作
業により製作できる。
先ず、基礎材料としてホウ珪酸ガラス繊維からなる細
径繊維（繊維径分布０．２〜２．６５μｍ、平均径０．
８５μｍ）と、前記細径繊維相互を補強するための少量
の太径繊維（Ｅガラス繊維：繊維径分布８〜２４μｍ）
を硫酸溶液にてｐＨ３．２にした水中に分散させ抄造す
る。
前記抄造後、バインダーとして溶液重量当たり２％の
アクリル樹脂、撥水剤として溶液重量当たり０．３％の
フッ素樹脂、及び溶液重量当たり１％のＬ−酒石酸を添
加したエマルジョンに浸漬し、シート状にして１３０℃
のスチームドライヤーで乾燥させてろ紙を製造する。
そして、蒸気ろ紙を断面ジグザグ状に折り、ウレタン
系樹脂にてアルミニウム型材の枠に密封して取り付ける
と、上記エアーフィルタは製作できる。This air filter can be manufactured by the following operations. First, a small-diameter fiber made of borosilicate glass fiber as a basic material (fiber diameter distribution: 0.2 to 2.65 μm, average diameter: 0.
85 μm) and a small amount of large diameter fibers (E glass fiber: fiber diameter distribution 8 to 24 μm) for reinforcing the small diameter fibers.
Is dispersed in water adjusted to pH 3.2 with a sulfuric acid solution for papermaking. After the above-mentioned papermaking, the sheet-like material was dipped in an emulsion containing 2% acrylic resin as a binder, 0.3% fluororesin as a water repellent, and 1% L-tartaric acid as a water repellent. To 130 ° C
The filter paper is manufactured by drying with a steam dryer. The air filter can be manufactured by folding the steam filter paper in a zigzag cross section and sealingly attaching it to a frame of aluminum mold material with urethane resin.
【００２０】ここで、このエアーフィルタをクリーンル
ームに取り付けホウ素濃度を測定したところ、クリーン
ルーム内のホウ素濃度は４ｎｇ／ｍ3 であった。When this air filter was attached to a clean room and the boron concentration was measured, the boron concentration in the clean room was 4 ng / m 3 .
【００２１】なお、上記実施例では、１３０℃のスチー
ムドライヤーで乾燥させて製造したろ紙を使用してエア
ーフィルタを構成させたが、これにかえて１００℃のス
チームドライヤーで乾燥させて製造したろ紙をエアーフ
ィルター枠に取り付けたものとしてもよい。このエアー
フィルタを使用した場合、クリーンルーム内のホウ素濃
度は２ｎｇ／ｍ3 であった。In the above embodiment, the air filter was constructed by using the filter paper produced by drying with the steam dryer at 130 ° C. Instead, the filter paper produced by drying with the steam dryer at 100 ° C. was used. May be attached to the air filter frame. When this air filter was used, the boron concentration in the clean room was 2 ng / m 3 .
【００２２】また、上記実施例では、ガラス繊維を分散
させる水溶液のｐＨ調整液として硫酸溶液を採用した
が、これにかえて、Ｌ−酒石酸、硝酸、クエン酸の溶液
が採用できる。この場合のクリーンルーム内のホウ素濃
度は表２に示した値であると予想できる。In the above embodiment, the sulfuric acid solution is used as the pH adjusting solution of the aqueous solution in which the glass fibers are dispersed, but instead of this, a solution of L-tartaric acid, nitric acid and citric acid can be used. The boron concentration in the clean room in this case can be expected to be the values shown in Table 2.
【００２３】更に、上記実施例ではガラス繊維を分散さ
せるための水溶液のｐＨを３．２としているが、前記水
溶液のｐＨを３．０〜３．５とすることもできる。つま
り、前記ｐＨの範囲であれば図３に示すように、ホウ素
発生量は１０ｎｇ／ｍ3 以下に抑えられる。Ｌ−酒石
酸、硝酸、クエン酸を使用して水溶液のｐＨ調整した場
合も同様である。Further, although the pH of the aqueous solution for dispersing the glass fibers is 3.2 in the above embodiment, the pH of the aqueous solution can be 3.0 to 3.5. That is, in the pH range, as shown in FIG. 3, the amount of boron generated can be suppressed to 10 ng / m 3 or less. The same applies when the pH of the aqueous solution is adjusted using L-tartaric acid, nitric acid, and citric acid.
【００２４】[0024]
【発明の効果】作用に記載した〜の内容から、生産
性が低下せず、粒子を捕集でき且つホウ素濃度を安定し
て１０ｎｇ／ｍ3 以下に抑えることができるろ紙及びこ
れを利用したエアーフィルタを提供できた。From the contents of (1) to (3) described in the action, the filter paper and the air using the filter paper, which does not lower the productivity, can collect the particles and can stably suppress the boron concentration to 10 ng / m 3 or less. I was able to provide a filter.
【図１】ホウ素捕集評価に使用した装置の概念図。FIG. 1 is a conceptual diagram of an apparatus used for boron collection evaluation.
【図２】供試フィルタからのホウ素発生量評価に使用し
た装置の概念図。FIG. 2 is a conceptual diagram of an apparatus used for evaluating the amount of boron generated from a test filter.
【図３】ガラス繊維を分散させるための水溶液について
ｐＨをかえて抄紙した場合のホウ素発生量を示すグラ
フ。FIG. 3 is a graph showing the amount of boron generated when the pH of an aqueous solution for dispersing glass fibers is changed and papermaking is performed.
１０ａ 流量計 １０ｂ 流量計 １１ メンブレンフィルタ １２ ホウ酸水溶液 １３ メンブレンフィルタ １５ａ 純水 １５ｂ 純水 １５ｃ 純水 １５ｄ 純水 １６ａ 流量計 １６Ｂ 流量計 ２０ 供試ろ紙 ２１ａ 純水バブラ ２１ｂ 純水バブラ ２２ 流量計 ２３ エアーポンプ 10a flow meter 10b flow meter 11 Membrane filter 12 Boric acid aqueous solution 13 Membrane filter 15a pure water 15b Pure water 15c pure water 15d pure water 16a flow meter 16B flow meter 20 Sample filter paper 21a Pure water bubbler 21b Pure water bubbler 22 Flow meter 23 Air pump
Claims (2)
選択された酸にてｐＨを３．０〜３．５にした水溶液に
繊維径が０．２〜１２μｍのガラス繊維を分散させて湿
式抄紙し、この抄紙したものにＬ−酒石酸を添着して成
ることを特徴とするろ紙。1. A glass fiber having a fiber diameter of 0.2 to 12 μm dispersed in an aqueous solution having a pH of 3.0 to 3.5 with an acid selected from sulfuric acid, L-tartaric acid, nitric acid and citric acid. A filter paper characterized by being formed by wet papermaking, and the papermaking product being impregnated with L-tartaric acid.
成るエアーフィルタ。2. An air filter comprising the filter paper according to claim 1 as a constituent member.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05861495A JP3516222B2 (en) | 1995-03-17 | 1995-03-17 | Filter paper and air filter using the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05861495A JP3516222B2 (en) | 1995-03-17 | 1995-03-17 | Filter paper and air filter using the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08252414A JPH08252414A (en) | 1996-10-01 |
| JP3516222B2 true JP3516222B2 (en) | 2004-04-05 |
Family
ID=13089433
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP05861495A Expired - Fee Related JP3516222B2 (en) | 1995-03-17 | 1995-03-17 | Filter paper and air filter using the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3516222B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101644012B (en) * | 2009-08-10 | 2011-05-11 | 重庆再升科技发展有限公司 | Preparation method of ULPA ultra performance air filter material |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102330388A (en) * | 2011-06-22 | 2012-01-25 | 苏州维艾普新材料有限公司 | Forming method of glass wool core material |
| CN102330387A (en) * | 2011-06-22 | 2012-01-25 | 苏州维艾普新材料有限公司 | Method for cutting finished glass wool core material product |
| CN102330379A (en) * | 2011-06-22 | 2012-01-25 | 苏州维艾普新材料有限公司 | Pulping method of glass wool core material |
| CN102330376A (en) * | 2011-06-22 | 2012-01-25 | 苏州维艾普新材料有限公司 | Pulping method of glass wool core material |
| CN102330389A (en) * | 2011-07-13 | 2012-01-25 | 苏州维艾普新材料有限公司 | Method for making high-performance vacuum heat insulating plate core material |
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1995
- 1995-03-17 JP JP05861495A patent/JP3516222B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101644012B (en) * | 2009-08-10 | 2011-05-11 | 重庆再升科技发展有限公司 | Preparation method of ULPA ultra performance air filter material |
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| JPH08252414A (en) | 1996-10-01 |
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