JPH0899008A - Electret filter - Google Patents
Electret filterInfo
- Publication number
- JPH0899008A JPH0899008A JP23731794A JP23731794A JPH0899008A JP H0899008 A JPH0899008 A JP H0899008A JP 23731794 A JP23731794 A JP 23731794A JP 23731794 A JP23731794 A JP 23731794A JP H0899008 A JPH0899008 A JP H0899008A
- Authority
- JP
- Japan
- Prior art keywords
- porous film
- electret filter
- electret
- electretized
- filter
- 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
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- Filtering Materials (AREA)
Abstract
(57)【要約】
【目的】 半導体、電子機器、薬品、生化学的物質等の
製造雰囲気や、電子機器の内部雰囲気を清浄化するため
等に用いるエレクトレットフィルタであって、粉塵に対
する高い捕集率を長時間維持するものを提供する。
【構成】 繊維シートの両面にエレクトレット化された
多孔質フィルムが積層されており、多孔質フィルムの一
方が正の電荷を、他方が負の電荷を有するものである。
(57) [Abstract] [Purpose] An electret filter used for cleaning the manufacturing atmosphere of semiconductors, electronic devices, chemicals, biochemical substances, etc., and the internal atmosphere of electronic devices. It provides the one that maintains the rate for a long time. [Structure] Electretized porous films are laminated on both sides of a fiber sheet, and one of the porous films has a positive charge and the other has a negative charge.
Description
【０００１】[0001]
【産業上の利用分野】本発明は半導体、電子機器、薬
品、生化学的物質等の製造雰囲気や、電子機器の内部雰
囲気を清浄化するため等に用いるエレクトレットフィル
タの改良に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an electret filter used for cleaning semiconductor, electronic equipment, chemicals, biochemical substances and the like, and for cleaning the internal atmosphere of electronic equipment.
【０００２】[0002]
【従来の技術】かようなエレクトレットフィルタとして
は、例えば、エレクトレット化多孔質フィルムを繊維シ
ートと貼り合わせたものが知られている（特開平４−１
６１２０８号公報）。2. Description of the Related Art As such an electret filter, for example, one in which an electretized porous film is bonded to a fiber sheet is known (Japanese Patent Laid-Open No. 4-1).
61208).
【０００３】[0003]
【発明が解決しようとする課題】上記従来のエレクトレ
ットフィルタは、図２に示すように、エレクトレット化
された多孔質フィルム１が繊維シート３の貼り合わせに
より補強された構造のものであり、該多孔質フィルム１
の一方の面が正の電荷を、他面が負の電荷を帯びてい
る。As shown in FIG. 2, the above-mentioned conventional electret filter has a structure in which an electretized porous film 1 is reinforced by bonding fibrous sheets 3 to each other. Quality film 1
One surface has a positive charge, and the other surface has a negative charge.
【０００４】このエレクトレットフィルタは多孔質フィ
ルムのエレクトレット化により集塵機能が高いものの、
このような電荷状態の持続時間は短く、比較的短時間で
粉塵に対する捕集率が低下してしまうという問題があ
る。従って、本発明は粉塵に対する高い捕集率を長時間
持続できるエレクトレット化フィルタを提供することを
目的とする。Although this electret filter has a high dust collecting function due to the electret of a porous film,
The duration of such a charge state is short, and there is a problem that the collection rate for dust is reduced in a relatively short time. Therefore, an object of the present invention is to provide an electret filter that can maintain a high dust collection rate for a long time.
【０００５】[0005]
【課題を解決するための手段】本発明に係るエレクトレ
ットフィルタは繊維シートの両面に多孔質フィルムが積
層されており、且つ、前記多孔質フィルムの一方が正の
電荷を、他方が負の電荷を有するようにエレクトレット
化されていることを特徴とするものである。In the electret filter according to the present invention, a porous film is laminated on both sides of a fiber sheet, and one of the porous films has a positive charge and the other has a negative charge. It is characterized by being electretized to have.
【０００６】図１は本発明に係るエレクトレットフィル
タの実例を示しており、繊維シート３の一方の面には正
の電荷を有するようにエレクトレット化された多孔質フ
ィルム１が、他面には負の電荷を有するようにエレクト
レット化された多孔質フィルム２が積層されている。多
孔質フィルムと、繊維シートの積層は接着や熱融着によ
り行うことができる。ただし、多孔質フィルムと繊維シ
ートは点状、筋状、網目状等のように部分的に接着や熱
融着させ、フィルタの表面側から裏面側への空気の流通
を維持し得る積層構造とする。FIG. 1 shows an example of the electret filter according to the present invention. One surface of the fiber sheet 3 is a porous film 1 which is electretized so as to have a positive charge, and the other surface is negative. The porous film 2 which has been electretized so as to have the electric charge of is laminated. Lamination of the porous film and the fiber sheet can be performed by adhesion or heat fusion. However, the porous film and the fibrous sheet have a laminated structure capable of maintaining the flow of air from the front surface side to the back surface side of the filter by partially adhering or heat-sealing such as dots, stripes, or meshes. To do.
【０００７】なお、上記図１に示すエレクトレットフィ
ルタでは繊維シートがエレクトレット化されていない
が、本発明においては繊維シートがエレクトレット化さ
れていてもよい。Although the fibrous sheet is not electretized in the electret filter shown in FIG. 1, the fibrous sheet may be electretized in the present invention.
【０００８】本発明において用いる多孔質フィルムはエ
レクトレット化できるものであればよく、例えば、ポリ
テトラフルオロエチレン（以下、「ＰＴＦＥ」とい
う）、テトラフルオロエチレン−パーフルオロアルキル
ビニルエーテル共重合体、テトラフルオロエチレン−ヘ
キサフルオロプロピレン共重合体、エチレン−テトラフ
ルオロエチレン共重合体、ポリフッ化ビニリデン、ポリ
クロロトリフルオロエチレン、ポリプロピレン、ポリエ
チレン、ポリ４メチル１ペンテン、ポリ３メチル１ブテ
ン、ポリカーボネート、ポリエチレンテレフタレート、
等をその具体例として挙げることができる。この多孔質
フィルムの厚さ等は適宜設定できるが、通常、厚さ約５
〜５００μｍ、孔径約０．１〜１０μｍ、気孔率約７０
〜９５％のものが用いられる。The porous film used in the present invention may be any that can be electretized, and examples thereof include polytetrafluoroethylene (hereinafter referred to as "PTFE"), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and tetrafluoroethylene. -Hexafluoropropylene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, polypropylene, polyethylene, poly 4 methyl 1 pentene, poly 3 methyl 1 butene, polycarbonate, polyethylene terephthalate,
Etc. can be mentioned as a specific example. The thickness and the like of this porous film can be appropriately set, but normally the thickness is about 5
〜500 μm, Pore size about 0.1-10 μm, Porosity about 70
~ 95% is used.
【０００９】また、繊維シートとしては不織布や織布等
を用いることができる。この繊維シートの厚さ等も適宜
設定できるが、通常、厚さ約０．１〜５ｍｍ、目付１０
〜５００ｇ／ｍ2 である。Further, as the fibrous sheet, non-woven fabric, woven fabric or the like can be used. The thickness and the like of this fiber sheet can be appropriately set, but usually, the thickness is about 0.1 to 5 mm, and the basis weight is 10 mm.
~ 500 g / m 2 .
【００１０】なお、本発明においては粉塵に対する捕集
率をより長時間持続させるため、多孔質フィルムおよび
繊維シートとして、体積抵抗率が１×１０14Ω・ｃｍ以
上のものを用いるのが好適であることが判明している。In the present invention, it is preferable to use a porous film and a fiber sheet having a volume resistivity of 1 × 10 14 Ω · cm or more in order to keep the dust collection rate for a longer time. It turns out to be.
【００１１】このような本発明に係るエレクトレットフ
ィルタは、例えば、繊維シートの両面に多孔質フィルム
を点状、筋状、網目状等に部分的に接着あるいは熱融着
させ、次いで、この積層体に従来から行われている熱エ
レクトレット、エレクトロエレクトレット、メカノエレ
クトレット、ラジオエレクトレット、マグネットエレク
トレット等のエレクトレット化法を適用し多孔質フィル
ムをエレクトレット化することにより得ることができ
る。In such an electret filter according to the present invention, for example, a porous film is partially adhered or heat-sealed in a dot shape, a stripe shape, a mesh shape or the like on both surfaces of the fiber sheet, and then this laminated body is formed. It can be obtained by applying a conventional electret-forming method such as thermal electret, electro-electret, mechano-electret, radio-electret, magnet-electret, etc. to electretize the porous film.
【００１２】[0012]
【実施例】以下、実施例により本発明を更に詳細に説明
する。EXAMPLES The present invention will be described in more detail below with reference to examples.
【００１３】実施例１ 厚さ０．５ｍｍ、目付１００ｇ／ｍ2 、体積抵抗率１×
１０16Ω・ｃｍのポリプロピレン不織布の両面に、厚さ
１０μｍ、孔径２μｍ、気孔率９０％、体積抵抗率１×
１０16Ω・ｃｍのＰＴＦＥ多孔質フィルムを重ね合わ
せ、次いで、これを温度１５０℃に加熱された一対のエ
ンボスロール間を通すことにより不織布の両面にＰＴＦ
Ｅ多孔質フィルムが点状に熱融着された積層体を得る。Example 1 Thickness 0.5 mm, basis weight 100 g / m 2 , volume resistivity 1 ×
Both sides of 10 16 Ω · cm polypropylene non-woven fabric, thickness 10 μm, pore diameter 2 μm, porosity 90%, volume resistivity 1 ×
A PTFE porous film of 10 16 Ω · cm was overlaid, and then this was passed between a pair of embossing rolls heated to a temperature of 150 ° C.
E A layered product in which a porous film is heat-sealed in spots is obtained.
【００１４】次に、この積層体に対し、５ｋＶ／ｃｍに
てコロナ放電処理を行うことにより、一方のＰＴＦＥ多
孔質フィルムが正電荷を有し、他方のＰＴＦＥ多孔質フ
ィルムが負電荷を有するようにエレクトレット化された
フィルタ（図１と同構造）を得た。Next, this laminate is subjected to corona discharge treatment at 5 kV / cm so that one PTFE porous film has a positive charge and the other PTFE porous film has a negative charge. To obtain an electretized filter (having the same structure as in FIG. 1).
【００１５】このエレクトレットフィルタの正電荷を有
するＰＴＦＥ多孔質フィルムが風上側になるようにし、
粒径０．１〜０．１５μｍの粒子を１×１０10個／ｍ3
の割合で含む風（温度２５℃）を風速５．３ｃｍ／秒で
送風したとき、粒子の透過率は０．０６％であった。ま
た、このフィルタの圧力損失は３０ｍｍＡｑであった。
更に、このフィルタを温度２５℃の部屋で２週間放置し
た後、上記と同様な粒子透過試験を行ったところ、透過
率は０．０７％であり初期値をほぼ維持していた。The PTFE porous film having a positive charge of this electret filter is placed on the windward side,
1 × 10 10 particles / m 3 with a particle size of 0.1 to 0.15 μm
When a wind (temperature: 25 ° C.) contained at a rate of 5 was blown at a wind speed of 5.3 cm / sec, the particle transmittance was 0.06%. The pressure loss of this filter was 30 mmAq.
Further, this filter was allowed to stand in a room at a temperature of 25 ° C. for 2 weeks and then subjected to the same particle permeation test as described above. As a result, the transmittance was 0.07%, which was almost the same as the initial value.
【００１６】実施例２ ポリプロピレン不織布に代え、厚さ０．５ｍｍ、目付１
００ｇ／ｍ2 、体積抵抗率１×１０14Ω・ｃｍのポリエ
チレン不織布を用いること以外は実施例１と同様にして
エレクトレットフィルタを得た。Example 2 Instead of polypropylene non-woven fabric, a thickness of 0.5 mm and a basis weight 1
An electret filter was obtained in the same manner as in Example 1 except that a polyethylene non-woven fabric having a volume resistivity of 100 g / m 2 and 1 × 10 14 Ω · cm was used.
【００１７】このエレクトレットフィルタの性能を実施
例１と同様に試験したところ、粒子の透過率は０．０５
％、圧力損失は３０ｍｍＡｑであった。また、２週間放
置後の透過率は０．０９％であり初期値をほぼ維持して
いた。When the performance of this electret filter was tested in the same manner as in Example 1, the particle transmittance was 0.05.
%, The pressure loss was 30 mmAq. The transmittance after leaving for 2 weeks was 0.09%, which was almost the same as the initial value.
【００１８】実施例３ ポリプロピレン不織布に代え、厚さ０．５ｍｍ、目付１
００ｇ／ｍ2 、体積抵抗率１×１０13Ω・ｃｍのナイロ
ン不織布を用いること以外は実施例１と同様に作業して
エレクトレットフィルタを得た。このフィルタの粒子の
透過率は０．０６％、圧力損失は３０ｍｍＡｑであっ
た。また、２週間放置後の透過率は０．１％であった。Example 3 Instead of polypropylene non-woven fabric, the thickness is 0.5 mm and the basis weight is 1.
An electret filter was obtained in the same manner as in Example 1, except that a nylon non-woven fabric having a volume resistivity of 100 g / m 2 and a volume resistivity of 1 × 10 13 Ω · cm was used. The filter had a particle transmittance of 0.06% and a pressure loss of 30 mmAq. The transmittance after standing for 2 weeks was 0.1%.
【００１９】実施例４ ＰＴＦＥ多孔質フィルムに代え、厚さ１０μｍ、孔径２
μｍ、気孔率９０％、体積抵抗率１×１０14Ω・ｃｍの
ポリエチレン多孔質フィルムを用いること以外は実施例
１と同様に作業してエレクトレットフィルタを得た。こ
のフィルタの粒子の透過率は０．０６％、圧力損失は３
０ｍｍＡｑであった。また、２週間放置後の透過率は
０．１２％であった。Example 4 Instead of the PTFE porous film, the thickness was 10 μm and the pore size was 2
An electret filter was obtained in the same manner as in Example 1 except that a polyethylene porous film having a micrometer, a porosity of 90%, and a volume resistivity of 1 × 10 14 Ω · cm was used. The filter has a particle permeability of 0.06% and a pressure loss of 3
It was 0 mmAq. The transmittance after standing for 2 weeks was 0.12%.
【００２０】比較例 厚さ１２μｍ、孔径２μｍ、気孔率９０％、体積抵抗率
１×１０16Ω・ｃｍのＰＴＦＥ多孔質フィルムを実施例
１と同条件でコロナ放電処理することによりエレクトレ
ット化する。このエレクトレット化多孔質フィルムは一
方の面が正の電荷を、他面が負の電荷を有している。Comparative Example A PTFE porous film having a thickness of 12 μm, a pore diameter of 2 μm, a porosity of 90%, and a volume resistivity of 1 × 10 16 Ω · cm was subjected to corona discharge treatment under the same conditions as in Example 1 to be electretized. This electretized porous film has one side having a positive charge and the other side having a negative charge.
【００２１】このエレクトレット化多孔質フィルムの片
面に実施例１で用いたのと同じポリプロピレン不織布を
重ね合わせ、これを温度１５０℃に加熱された一対のエ
ンボスロール間を通すことにより、エレクトレット化Ｐ
ＴＦＥ多孔質フィルムの片面に不織布が点状に熱融着さ
れたエレクトレットフィルタ（図２と同構造）を得た。The same polypropylene non-woven fabric used in Example 1 was superposed on one surface of this electretized porous film, and this was passed between a pair of embossing rolls heated to a temperature of 150 ° C. to give an electretized P film.
An electret filter (having the same structure as in FIG. 2) in which a non-woven fabric was heat-sealed in a dot shape on one surface of the TFE porous film was obtained.
【００２２】このエレクトレットフィルタの性能を実施
例１と同様に試験したところ、粒子の透過率は０．０７
％、圧力損失は３０ｍｍＡｑであった。また、２週間放
置後には透過率が０．３％に増加した。When the performance of this electret filter was tested in the same manner as in Example 1, the particle transmittance was 0.07.
%, The pressure loss was 30 mmAq. Further, the transmittance increased to 0.3% after being left for 2 weeks.
【００２３】[0023]
【発明の効果】本発明は上記のように構成されているの
で、多孔質フィルムのエレクトレット化寿命が長く、粉
塵に対する高い捕集率を長時間持続できる。EFFECTS OF THE INVENTION Since the present invention is constructed as described above, the porous film has a long electret life and can maintain a high dust collection rate for a long time.
【図１】本発明に係るエレクトレットフィルタの実例を
示す正面図である。FIG. 1 is a front view showing an actual example of an electret filter according to the present invention.
【図２】従来のエレクトレットフィルタを示す正面図で
ある。FIG. 2 is a front view showing a conventional electret filter.
１ 多孔質フィルム ２ 多孔質フィルム ３ 繊維シート 1 Porous film 2 Porous film 3 Fiber sheet
Claims (2)
層されており、且つ、前記多孔質フィルムの一方が正の
電荷を、他方が負の電荷を有するようにエレクトレット
化されていることを特徴とするエレクトレットフィル
タ。1. A porous film is laminated on both sides of a fibrous sheet, and one of the porous films is electretized so as to have a positive charge and the other has a negative charge. Electret filter.
率が１×１０14Ω・ｃｍ以上である請求項１記載のエレ
クトレットフィルタ。2. The electret filter according to claim 1, wherein the non-woven fabric and the porous film have a volume resistivity of 1 × 10 14 Ω · cm or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23731794A JPH0899008A (en) | 1994-09-30 | 1994-09-30 | Electret filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23731794A JPH0899008A (en) | 1994-09-30 | 1994-09-30 | Electret filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0899008A true JPH0899008A (en) | 1996-04-16 |
Family
ID=17013580
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23731794A Pending JPH0899008A (en) | 1994-09-30 | 1994-09-30 | Electret filter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0899008A (en) |
-
1994
- 1994-09-30 JP JP23731794A patent/JPH0899008A/en active Pending
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