JPH01151916A - Production of electoret foamed opening material - Google Patents
Production of electoret foamed opening materialInfo
- Publication number
- JPH01151916A JPH01151916A JP30859287A JP30859287A JPH01151916A JP H01151916 A JPH01151916 A JP H01151916A JP 30859287 A JP30859287 A JP 30859287A JP 30859287 A JP30859287 A JP 30859287A JP H01151916 A JPH01151916 A JP H01151916A
- Authority
- JP
- Japan
- Prior art keywords
- opening
- foamed
- electoret
- air
- production
- 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
- 239000000463 material Substances 0.000 title claims abstract description 22
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 17
- 239000004088 foaming agent Substances 0.000 claims abstract description 4
- 239000000835 fiber Substances 0.000 claims description 18
- 239000006260 foam Substances 0.000 claims description 8
- 239000000155 melt Substances 0.000 claims description 3
- 239000000126 substance Substances 0.000 abstract description 11
- 238000001125 extrusion Methods 0.000 abstract description 4
- 239000000428 dust Substances 0.000 abstract description 3
- 238000004378 air conditioning Methods 0.000 abstract description 2
- 239000004156 Azodicarbonamide Substances 0.000 abstract 1
- XOZUGNYVDXMRKW-AATRIKPKSA-N azodicarbonamide Chemical compound NC(=O)\N=N\C(N)=O XOZUGNYVDXMRKW-AATRIKPKSA-N 0.000 abstract 1
- 235000019399 azodicarbonamide Nutrition 0.000 abstract 1
- 238000000034 method Methods 0.000 description 16
- 239000004745 nonwoven fabric Substances 0.000 description 9
- 239000004604 Blowing Agent Substances 0.000 description 7
- 239000003990 capacitor Substances 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 229920006113 non-polar polymer Polymers 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 239000002861 polymer material Substances 0.000 description 3
- 238000003892 spreading Methods 0.000 description 3
- 239000004743 Polypropylene Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- -1 polypropylene Polymers 0.000 description 2
- 229920001155 polypropylene Polymers 0.000 description 2
- 239000004793 Polystyrene Substances 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007380 fibre production Methods 0.000 description 1
- 239000006261 foam material Substances 0.000 description 1
- 229920001903 high density polyethylene Polymers 0.000 description 1
- 239000004700 high-density polyethylene Substances 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 238000002074 melt spinning Methods 0.000 description 1
- 229920005629 polypropylene homopolymer Polymers 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 229920005992 thermoplastic resin Polymers 0.000 description 1
Landscapes
- Filtering Materials (AREA)
- Chemical Or Physical Treatment Of Fibers (AREA)
- Nonwoven Fabrics (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、マット状、ウェッブ状にして空調システムの
除塵フィルター等に広く利用できるエレクトレット発泡
開繊体の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing an electret foam spread material that can be made into a mat or web form and widely used as dust removal filters for air conditioning systems.
（従来の技術）
従来、エレクトレット繊維の製造方法としては、無極性
高分子物質をフィルムに成形し、延伸した後、コロナ荷
電し、次いで荷電されたフィルムをニード斯ロールで開
繊して製造する方法や無極性高分子物質を溶融紡糸後、
延伸し、次いで不織布化してからコロナ荷電処理を施し
て製造する方法等が知られている。しかし、前者の方法
では、エレクトレット繊維を成形する前にフィルム化す
る工程、延伸する工程および開繊工程が必要であるため
、工程が繁雑であるばかシでなく、コストが高くなると
いう問題がある。一方、後者の方法では、不織布化して
からコロナ荷電処理を施すので、不織布が厚くなると不
織布の表層のみが荷電し、中間層の荷電が少なくなる。(Prior Art) Conventionally, the method for producing electret fibers involves forming a nonpolar polymer material into a film, stretching it, corona charging it, and then opening the charged film with a needling roll. After melt spinning method and non-polar polymeric material,
A manufacturing method is known in which the material is stretched, then made into a nonwoven fabric, and then subjected to a corona charging treatment. However, the former method requires a film-forming process, a stretching process, and an opening process before forming the electret fibers, so the process is not only complex but also costly. . On the other hand, in the latter method, corona charging treatment is performed after forming the nonwoven fabric, so that when the nonwoven fabric becomes thicker, only the surface layer of the nonwoven fabric is charged, and the intermediate layer is less charged.
従って、この不織布をフィルター等にして使用した場合
はエレクトレットフィルターとしての効力が低い等の難
点を有する。Therefore, when this nonwoven fabric is used as a filter, etc., it has disadvantages such as low effectiveness as an electret filter.
（発明が解決しようとする問題点）
本発明の目的は、前記従来のエレクトレット繊維の製造
方法の欠点を克服して、高度に荷電されたエレクトレッ
ト発泡開繊体を簡素化された工程で簡潔に製造する方法
を提供することにある。(Problems to be Solved by the Invention) An object of the present invention is to overcome the drawbacks of the conventional electret fiber manufacturing method and easily produce highly charged electret foamed fibers in a simplified process. The purpose is to provide a manufacturing method.
（問題点を解決するための手段）
本発明によって上記目的を達成し得るエレクトレット発
泡開繊体の製造方法が提供される。(Means for Solving the Problems) The present invention provides a method for producing an electret foamed fiber-opening body that can achieve the above object.
すなわち、本発明は、発泡剤を含む無極性高分子物質を
スリットノズルから溶融押出し、溶融押出物の開繊開始
点から発泡開繊体が引取シ装置に引取られるまでの間に
、該開繊体にコロナ荷電処理を施すことを特徴とするエ
レクトレット発泡開繊体の製造方法に関する。That is, the present invention melt-extrudes a non-polar polymeric substance containing a foaming agent from a slit nozzle, and processes the opening process between the opening point of the molten extrudate and the time when the expanded expanded body is taken up by a take-up device. The present invention relates to a method for manufacturing an electret foamed fiber-opening material, which is characterized by subjecting the material to corona charging treatment.
本発明において使用される無極性高分子物質としては、
通常無極性高分子物質と呼ばれているものであればいず
れでもよく、その多くは誘電損失（誘電正接）が０．０
００５以下（ＡＳＴＭ Ｄ １５０ 。The non-polar polymeric substances used in the present invention include:
Any material that is normally called a non-polar polymer substance may be used, and most of them have a dielectric loss (dielectric loss tangent) of 0.0.
005 or less (ASTM D 150).
６０Ｈｚ）、体積固有抵抗（ＡＳＴＭ Ｄ ２５７．２
３℃。60Hz), volume resistivity (ASTM D 257.2
3℃.
相対湿度５０％）が１０〜１００ｍの範囲のものである
。具体例としてはポリプロピレン、高密度ポリエチレン
、ポリスチレン等があげラレル。relative humidity (50%) is in the range of 10 to 100 m. Specific examples include polypropylene, high-density polyethylene, polystyrene, etc.
これらの無極性高分子物質は、２種以上混合して使用し
てもよい。また、これらの無極性高分子物質を主成分と
する他の熱可塑性樹脂との混合物でも良い。Two or more of these nonpolar polymeric substances may be used in combination. Alternatively, a mixture of these nonpolar polymeric substances with other thermoplastic resins as a main component may be used.
上記無極性高分子物質には、発泡剤が配合される。発泡
剤は、無極性高分子物質の成形温度以下、好ましくは無
極性高分子物質の成形温度から５０℃低い温度〜無極性
高分子物質の成形温度までの範囲内で気化または分解す
るものであればいずれでもよく、例えば無極性高分子物
質としてポリプロピレンを使用する場合は、分解温度が
１９５〜２００℃の固体発泡剤アゾジカルデンアミドが
好適に用いられる０発泡剤の配合量は、無極性高分子物
質１００重量部に対して０．２〜３重量部が好ましい０
発泡剤の配合量が０．２重量部未満では気泡が少なく、
開繊度が粗い、また、発泡剤の配合量が３重量部を越え
ると気泡が大きくなって開繊度が不均一になる。A blowing agent is blended into the non-polar polymeric substance. The blowing agent may be one that vaporizes or decomposes below the molding temperature of the non-polar polymeric material, preferably within a temperature range of 50°C lower than the molding temperature of the non-polar polymeric material to the molding temperature of the non-polar polymeric material. For example, when polypropylene is used as the non-polar polymeric substance, azodicardenamide, a solid blowing agent with a decomposition temperature of 195 to 200°C, is preferably used. Preferably 0.2 to 3 parts by weight per 100 parts by weight of the molecular substance.
If the amount of the blowing agent is less than 0.2 parts by weight, there will be few bubbles;
If the degree of opening is coarse, and if the amount of the blowing agent exceeds 3 parts by weight, the air bubbles will become large and the degree of opening will become uneven.
本発明で発泡開繊体を製造するために使用される装置は
、狭い間隙を環状に持ったスリットノズルヲ有する所謂
インフレーションフィルム成形装置である。The apparatus used in the present invention to produce the expanded fiber-formed material is a so-called blown film forming apparatus having a slit nozzle having an annular narrow gap.
以下、図面を用いて本発明を説明する。第１図は、本発
明のエレクトレット発泡開繊体を製造するだめに使用さ
れる装置の一例を示す概略図である。The present invention will be explained below using the drawings. FIG. 1 is a schematic diagram showing an example of an apparatus used for manufacturing the electret foam spread material of the present invention.
無極性高分子物質および発泡剤からなる組成物を押出機
１によシ混練し、ダイ２の狭い環状の間隙を有するスリ
ットノズル３から溶融押出しする。A composition consisting of a non-polar polymeric substance and a blowing agent is kneaded in an extruder 1 and melt-extruded through a slit nozzle 3 having a narrow annular gap of a die 2.
押出直後に溶融押出物４をニアリング５から吹き出す空
気によって風冷する。スリ、トノズル３から出た溶融押
出物４は、大気圧の下では気泡が拡大すると共に、引取
によって気泡が破裂し、開繊状態に至る。開繊開始点６
より上部に設けた環状電極７からコロナ荷電を受は荷電
された発泡開繊体８に成形される。Immediately after extrusion, the molten extrudate 4 is cooled by air blown out from the near ring 5. In the molten extrudate 4 discharged from the pickpocket nozzle 3, the bubbles expand under atmospheric pressure, and the bubbles burst when taken off, resulting in an open fiber state. Opening starting point 6
It receives corona charge from the annular electrode 7 provided at the upper part, and is formed into a charged expanded foam fiber body 8.
風冷によって溶融押出物４の粘度を上げて気泡の拡大集
合を防ぎ、細かい均一な開繊をもたらすには開繊開始点
６はスリットノズル３面よシ、上部３−以内が好ましく
、そのようにニアリング５からの風量を調節する必要が
ある。In order to increase the viscosity of the molten extrudate 4 by air cooling and prevent the expansion and aggregation of air bubbles, and to bring about fine and uniform opening, the opening starting point 6 is preferably within the upper part 3 of the slit nozzle 3 surface. It is necessary to adjust the air volume from near ring 5.
荷電を与える環状電極７は、溶融押出物４の開繊開始点
６から発泡開繊体が引取シ装置に引取られるまでの間の
任意の位置に、発泡開繊体が環状電極７の中を通シ抜け
れるように設ける。荷電効率を良好ならしめるための好
ましい環状電極７の位置は、発泡開繊体が使用した無極
性高分子物質の融点に近い温度を保っている位置であり
、さらに好ましくは溶融押出物４の開繊開始点６に近い
所、具体的には開繊開始点６より上部へ２０α以内の位
置に設けることが望ましい。The annular electrode 7 that gives a charge is placed at any position between the opening start point 6 of the melt extrudate 4 and the time when the expanded expanded body is taken up by a take-up device. Provide it so that it can be passed through. A preferable position of the annular electrode 7 in order to improve the charging efficiency is a position where the expanded foamed fiber body maintains a temperature close to the melting point of the nonpolar polymer material used, and more preferably a position where the expanded fiber body maintains a temperature close to the melting point of the nonpolar polymer material used. It is desirable to provide it at a location close to the fiber starting point 6, specifically at a position within 20α above the fiber opening starting point 6.
環状電極７と発泡開繊体の間隙は、荷電電圧によって変
化させる必要があシ、−概には決められない、荷電電圧
は、１ ｋＶ／ｍｍ以上が好ましい。環状電極７による
荷電では、対電極を設けないので１、５ ｋＶ／ｍ、程
度の荷電電圧が好ましい。それ以上の単位間隙当シの荷
電電圧をかけても荷電量の増大は期待できない。The gap between the annular electrode 7 and the expanded expanded fiber body needs to be changed depending on the charging voltage; it cannot be determined generally, but the charging voltage is preferably 1 kV/mm or more. For charging using the annular electrode 7, a charging voltage of about 1.5 kV/m is preferable since no counter electrode is provided. Even if a charging voltage of more than that per unit gap is applied, an increase in the amount of charge cannot be expected.
本発明の製造方法によれば、半永久的な荷電状態を保持
したエレクトレット発泡開繊体が得られ、この開繊体は
不織布加工する等の後工程によシ、除塵効率の良いフィ
ルター等に有効に利用される。According to the manufacturing method of the present invention, an electret foam spread body that maintains a semi-permanently charged state can be obtained, and this spread fiber body can be used in post-processes such as non-woven fabric processing, and is effective for filters with high dust removal efficiency. used for.
（実施例）
以下、実施例および比較例をあげて本発明をさらに詳細
に説明する。(Example) Hereinafter, the present invention will be explained in further detail by giving Examples and Comparative Examples.
実施例１
メルトフローインデックスが７１１１Ｏ分（ＪＩＳ Ｋ
−６７５８）のポリゾロピレンホモポリマー１００重量
部に、発泡剤としてアゾジカル？ンアミド（分解温度１
９５〜２００℃）０．８重量部を配合した。得られた組
成物を５０ｍｍφのインフレーション押出機（１００：
ｘｉφダイ使用）により、押出温度２００℃で押出し、
溶融押出物の開繊開始点をスリットノズルよシ上部３１
Ｍの位置に保持するようにニアリング風量を選定した。Example 1 Melt flow index is 7111O min (JIS K
100 parts by weight of the polyzolopyrene homopolymer (-6758) and azodicarol as a blowing agent. Amide (decomposition temperature 1
95-200°C) 0.8 parts by weight was blended. The obtained composition was passed through a 50 mmφ inflation extruder (100:
extrusion at an extrusion temperature of 200°C using a xiφ die,
Place the opening point of the melt extrudate through the slit nozzle at the upper part 31.
The nearing air volume was selected to maintain the position M.
ここでの引取速度は２０ｍ／分である。開繊体を溶融押
出物の開繊開始点よシ上部１０ｃｎ１の位置で開繊体と
の間隙が１０罰にある環状電極（１５ｋｖ）を通した後
、連続的に引取り装置に引取った。得られたエレクトレ
ット発泡開繊体は、網目が細く、かつ規則正しく割裂し
ていた。次いで、この発泡開繊体から目付５０ ！／ｒ
ｒ？のフィルターを作製した。このフィルターの表面電
荷密度を第２図に示した装置を用い、下記に従って測定
した。すなわち、最初に測定電極を試料（フィルター）
から十分に離しておくと同時に、スイッチ１１を短絡す
る。次に、スイッチ１１をコンデンサ１２側に倒す。そ
して、測定電極を試料表面に降ろすと測定電極に誘導さ
れた電荷がコンデンサ１２に移動して電位差Ｖを生じて
表面電荷密度が測定できる。The take-up speed here is 20 m/min. The fiber-spreading body was passed through a ring electrode (15kV) with a gap of 10 mm between the fiber-spreading body and the fiber-spreading body at a position 10cn1 above the fiber-opening start point of the melted extrudate, and then continuously taken to a pulling device. . The obtained expanded electret foam had a fine mesh and was regularly split. Next, from this expanded foamed fiber, the basis weight was 50! /r
r? A filter was created. The surface charge density of this filter was measured using the apparatus shown in FIG. 2 according to the following procedure. In other words, first place the measurement electrode on the sample (filter).
At the same time, short-circuit the switch 11. Next, turn the switch 11 to the capacitor 12 side. Then, when the measurement electrode is lowered onto the sample surface, the charges induced in the measurement electrode move to the capacitor 12, creating a potential difference V, and the surface charge density can be measured.
Ｃ：コンデンサの静電容量（Ｆ）
Ｓ：試料の表面積（、、り
Ｖ：電位差（Ｖ）
フィル−の表面電荷密度は、３ Ｘ １０”−９クーロ
ン／ｄであシ、十分な荷電量を有していた。C: Capacitance of the capacitor (F) S: Surface area of the sample (, V: Potential difference (V) The surface charge density of the fill is 3 x 10"-9 coulombs/d, which is a sufficient amount of charge. It had
実施例２
実施例１で環状電極と発泡開繊体との間隙を２０１ｍと
し、環状電極の加電電圧を１０ ｋＶとした以外は、実
施例１と同様な方法でエレクトレット発泡開繊体を成形
し、これからフィルターを作製した。得られたフィルタ
ーの表面電荷密度は、１×１０ クーロン／−であった
。Example 2 An electret foam spread material was molded in the same manner as in Example 1, except that the gap between the annular electrode and the expanded foam material was 201 m and the voltage applied to the annular electrode was 10 kV. I made a filter from this. The surface charge density of the obtained filter was 1 x 10 coulombs/-.
比較例１
実施例１で使用したものと同一のポリプロピレンホモポ
リマーを実施例１と同一の装置を用いて、同一条件で押
出し、スリットノズルより上部１５αの位置で環状電極
とフィルムとの間隙を１０Ｂ。Comparative Example 1 The same polypropylene homopolymer used in Example 1 was extruded using the same equipment as in Example 1 under the same conditions, and the gap between the annular electrode and the film was 10B at a position 15α above the slit nozzle. .
環状電極の荷電電圧を１５ ｋＶでフィルムに荷電して
エレクトレットフィルムを得た。次いで、得らレタエレ
クトレットフィルムをニードルローラーで小繊維化し、
ウニツバ−によって不織布化した。An electret film was obtained by charging the film with a charging voltage of 15 kV from the annular electrode. Next, the obtained reta electret film was made into small fibers using a needle roller,
It was made into a non-woven fabric by Unituber.
この不織布から目付５０１／ｎ？のフィルターを作製し
た。このフィルターの表面電荷密度は、３×１ｏ−１０
クーロン／ ｔｒ＆であった。This non-woven fabric has a basis weight of 501/n? A filter was created. The surface charge density of this filter is 3×1o-10
It was coulomb/tr&.
（発明の効果）
本発明の製造方法によれば、フィルム成形した後の延伸
工程および開繊工程を省略することができるために、エ
レクトレット繊維製造装置と製法の大幅な簡素化ができ
てコストダウンが図れる。(Effects of the Invention) According to the production method of the present invention, it is possible to omit the stretching process and opening process after film forming, so the electret fiber production equipment and production method can be significantly simplified and costs can be reduced. can be achieved.
まだ、本発明の製造方法によれば、不織布後のコロナ荷
電を必要としないので、各繊維素には高い荷電が可能と
なり、フィルター材として適切なエレクトレット発泡開
繊体を製造することができる。However, according to the manufacturing method of the present invention, since corona charging after the nonwoven fabric is not required, each cellulose can be highly charged, and an expanded electret fiber fiber suitable as a filter material can be manufactured.
第１図は本発明のエレクトレット発泡開繊体の製造方法
に使用される装置の一例を示す概略図、第２図は表面荷
電密度の測定装置を示す概略図である。
ｌ：押出機、２：ダイ、３ニスリツトノズル、４：溶融
押出物、５：エアリング、６：開繊開始点、７二環状電
極、８：エレクトレット発泡開繊体、９：測定電極、１
０：試料、１１：スイッチ、１２：コンデンサ。
特許出願人 昭和電工株式会社
代 理 人 弁理士菊地精−
（ほか１名）FIG. 1 is a schematic diagram showing an example of an apparatus used in the method for manufacturing an electret foam spread material of the present invention, and FIG. 2 is a schematic diagram showing an apparatus for measuring surface charge density. 1: extruder, 2: die, 3 slit nozzle, 4: melt extrudate, 5: air ring, 6: opening starting point, 7 two-ring electrode, 8: electret foamed fiber opening body, 9: measurement electrode, 1
0: sample, 11: switch, 12: capacitor. Patent applicant: Showa Denko Co., Ltd. Representative: Patent attorney Sei Kikuchi (1 other person)
Claims (1)
融押出し、溶融押出物の開繊開始点から発泡開繊体が引
取り装置に引取られるまでの間に、該開繊体にコロナ荷
電処理を施すことを特徴とするエレクトレット発泡開繊
体の製造方法。A non-polar polymeric material containing a foaming agent is melt-extruded from a slit nozzle, and the spread fiber body is subjected to corona charging treatment from the starting point of opening the melt extrudate until the foam spread body is taken up by a take-up device. 1. A method for producing an electret foamed fiber-opening material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30859287A JPH01151916A (en) | 1987-12-08 | 1987-12-08 | Production of electoret foamed opening material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30859287A JPH01151916A (en) | 1987-12-08 | 1987-12-08 | Production of electoret foamed opening material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01151916A true JPH01151916A (en) | 1989-06-14 |
Family
ID=17982893
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30859287A Pending JPH01151916A (en) | 1987-12-08 | 1987-12-08 | Production of electoret foamed opening material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01151916A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008213000A (en) * | 2007-03-06 | 2008-09-18 | Aida Eng Ltd | Press machine |
-
1987
- 1987-12-08 JP JP30859287A patent/JPH01151916A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008213000A (en) * | 2007-03-06 | 2008-09-18 | Aida Eng Ltd | Press machine |
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